[PATCH] powerpc: Kill _machine and hard-coded platform numbers

This removes statically assigned platform numbers and reworks the
powerpc platform probe code to use a better mechanism.  With this,
board support files can simply declare a new machine type with a
macro, and implement a probe() function that uses the flattened
device-tree to detect if they apply for a given machine.

We now have a machine_is() macro that replaces the comparisons of
_machine with the various PLATFORM_* constants.  This commit also
changes various drivers to use the new macro instead of looking at
_machine.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>

63 files changed, 560 insertions, 543 deletions

diff --git a/Documentation/powerpc/booting-without-of.txt b/Documentation/powerpc/booting-without-of.txt
index ee551c6ea235..217e51768b87 100644
--- a/Documentation/powerpc/booting-without-of.txt
+++ b/Documentation/powerpc/booting-without-of.txt
@@ -719,6 +719,11 @@ address which can extend beyond that limit.
     - model : this is your board name/model
     - #address-cells : address representation for "root" devices
     - #size-cells: the size representation for "root" devices
+    - device_type : This property shouldn't be necessary. However, if
+      you decide to create a device_type for your root node, make sure it
+      is _not_ "chrp" unless your platform is a pSeries or PAPR compliant
+      one for 64-bit, or a CHRP-type machine for 32-bit as this will
+      matched by the kernel this way.
 
   Additionally, some recommended properties are:
 
diff --git a/arch/powerpc/kernel/asm-offsets.c b/arch/powerpc/kernel/asm-offsets.c
index 882889b15926..54b48f330051 100644
--- a/arch/powerpc/kernel/asm-offsets.c
+++ b/arch/powerpc/kernel/asm-offsets.c
@@ -105,8 +105,6 @@ int main(void)
         DEFINE(ICACHEL1LINESIZE, offsetof(struct ppc64_caches, iline_size));
         DEFINE(ICACHEL1LOGLINESIZE, offsetof(struct ppc64_caches, log_iline_size));
         DEFINE(ICACHEL1LINESPERPAGE, offsetof(struct ppc64_caches, ilines_per_page));
-        DEFINE(PLATFORM_LPAR, PLATFORM_LPAR);
-
         /* paca */
         DEFINE(PACA_SIZE, sizeof(struct paca_struct));
         DEFINE(PACAPACAINDEX, offsetof(struct paca_struct, paca_index));
diff --git a/arch/powerpc/kernel/nvram_64.c b/arch/powerpc/kernel/nvram_64.c
index 6c3989f6247d..ada50aa5b600 100644
--- a/arch/powerpc/kernel/nvram_64.c
+++ b/arch/powerpc/kernel/nvram_64.c
@@ -160,7 +160,7 @@ static int dev_nvram_ioctl(struct inode *inode, struct file *file,
         case IOC_NVRAM_GET_OFFSET: {
                 int part, offset;
 
-                if (_machine != PLATFORM_POWERMAC)
+                if (!machine_is(powermac))
                         return -EINVAL;
                 if (copy_from_user(&part, (void __user*)arg, sizeof(part)) != 0)
                         return -EFAULT;
@@ -444,7 +444,7 @@ static int nvram_setup_partition(void)
          * in our nvram, as Apple defined partitions use pretty much
          * all of the space
          */
-        if (_machine == PLATFORM_POWERMAC)
+        if (machine_is(powermac))
                 return -ENOSPC;
 
         /* see if we have an OS partition that meets our needs.
diff --git a/arch/powerpc/kernel/pci_32.c b/arch/powerpc/kernel/pci_32.c
index 704c846b2b0f..b129d2e4b759 100644
--- a/arch/powerpc/kernel/pci_32.c
+++ b/arch/powerpc/kernel/pci_32.c
@@ -787,7 +787,7 @@ pci_busdev_to_OF_node(struct pci_bus *bus, int devfn)
          * fix has to be done by making the remapping per-host and always
          * filling the pci_to_OF map. --BenH
          */
-        if (_machine == _MACH_Pmac && busnr >= 0xf0)
+        if (machine_is(powermac) && busnr >= 0xf0)
                 busnr -= 0xf0;
         else
 #endif
@@ -1728,7 +1728,7 @@ long sys_pciconfig_iobase(long which, unsigned long bus, unsigned long devfn)
          * (bus 0 is HT root), we return the AGP one instead.
          */
 #ifdef CONFIG_PPC_PMAC
-        if (_machine == _MACH_Pmac && machine_is_compatible("MacRISC4"))
+        if (machine_is(powermac) && machine_is_compatible("MacRISC4"))
                 if (bus == 0)
                         bus = 0xf0;
 #endif /* CONFIG_PPC_PMAC */
diff --git a/arch/powerpc/kernel/proc_ppc64.c b/arch/powerpc/kernel/proc_ppc64.c
index 7ba42a405f41..3c2cf661f6d9 100644
--- a/arch/powerpc/kernel/proc_ppc64.c
+++ b/arch/powerpc/kernel/proc_ppc64.c
@@ -23,6 +23,7 @@
 #include <linux/slab.h>
 #include <linux/kernel.h>
 
+#include <asm/machdep.h>
 #include <asm/vdso_datapage.h>
 #include <asm/rtas.h>
 #include <asm/uaccess.h>
@@ -51,7 +52,7 @@ static int __init proc_ppc64_create(void)
         if (!root)
                 return 1;
 
-        if (!(platform_is_pseries() || _machine == PLATFORM_CELL))
+        if (!machine_is(pseries) && !machine_is(cell))
                 return 0;
 
         if (!proc_mkdir("rtas", root))
diff --git a/arch/powerpc/kernel/prom.c b/arch/powerpc/kernel/prom.c
index a2bc433f3610..4336390bcf34 100644
--- a/arch/powerpc/kernel/prom.c
+++ b/arch/powerpc/kernel/prom.c
@@ -383,14 +383,14 @@ static int __devinit finish_node_interrupts(struct device_node *np,
                         /* Apple uses bits in there in a different way, let's
                          * only keep the real sense bit on macs
                          */
-                        if (_machine == PLATFORM_POWERMAC)
+                        if (machine_is(powermac))
                                 sense &= 0x1;
                         np->intrs[intrcount].sense = map_mpic_senses[sense];
                 }
 
 #ifdef CONFIG_PPC64
                 /* We offset irq numbers for the u3 MPIC by 128 in PowerMac */
-                if (_machine == PLATFORM_POWERMAC && ic && ic->parent) {
+                if (machine_is(powermac) && ic && ic->parent) {
                         char *name = get_property(ic->parent, "name", NULL);
                         if (name && !strcmp(name, "u3"))
                                 np->intrs[intrcount].line += 128;
@@ -570,6 +570,18 @@ int __init of_scan_flat_dt(int (*it)(unsigned long node,
         return rc;
 }
 
+unsigned long __init of_get_flat_dt_root(void)
+{
+        unsigned long p = ((unsigned long)initial_boot_params) +
+                initial_boot_params->off_dt_struct;
+
+        while(*((u32 *)p) == OF_DT_NOP)
+                p += 4;
+        BUG_ON (*((u32 *)p) != OF_DT_BEGIN_NODE);
+        p += 4;
+        return _ALIGN(p + strlen((char *)p) + 1, 4);
+}
+
 /**
  * This  function can be used within scan_flattened_dt callback to get
  * access to properties
@@ -612,6 +624,25 @@ void* __init of_get_flat_dt_prop(unsigned long node, const char *name,
         } while(1);
 }
 
+int __init of_flat_dt_is_compatible(unsigned long node, const char *compat)
+{
+        const char* cp;
+        unsigned long cplen, l;
+
+        cp = of_get_flat_dt_prop(node, "compatible", &cplen);
+        if (cp == NULL)
+                return 0;
+        while (cplen > 0) {
+                if (strncasecmp(cp, compat, strlen(compat)) == 0)
+                        return 1;
+                l = strlen(cp) + 1;
+                cp += l;
+                cplen -= l;
+        }
+
+        return 0;
+}
+
 static void *__init unflatten_dt_alloc(unsigned long *mem, unsigned long size,
                                        unsigned long align)
 {
@@ -686,7 +717,7 @@ static unsigned long __init unflatten_dt_node(unsigned long mem,
 #ifdef DEBUG
                                 if ((strlen(p) + l + 1) != allocl) {
                                         DBG("%s: p: %d, l: %d, a: %d\n",
-                                            pathp, strlen(p), l, allocl);
+                                            pathp, (int)strlen(p), l, allocl);
                                 }
 #endif
                                 p += strlen(p);
@@ -951,7 +982,6 @@ static int __init early_init_dt_scan_cpus(unsigned long node,
 static int __init early_init_dt_scan_chosen(unsigned long node,
                                             const char *uname, int depth, void *data)
 {
-        u32 *prop;
         unsigned long *lprop;
         unsigned long l;
         char *p;
@@ -962,14 +992,6 @@ static int __init early_init_dt_scan_chosen(unsigned long node,
             (strcmp(uname, "chosen") != 0 && strcmp(uname, "chosen@0") != 0))
                 return 0;
 
-        /* get platform type */
-        prop = (u32 *)of_get_flat_dt_prop(node, "linux,platform", NULL);
-        if (prop == NULL)
-                return 0;
-#ifdef CONFIG_PPC_MULTIPLATFORM
-        _machine = *prop;
-#endif
-
 #ifdef CONFIG_PPC64
         /* check if iommu is forced on or off */
         if (of_get_flat_dt_prop(node, "linux,iommu-off", NULL) != NULL)
@@ -996,15 +1018,15 @@ static int __init early_init_dt_scan_chosen(unsigned long node,
          * set of RTAS infos now if available
          */
         {
-                u64 *basep, *entryp;
+                u64 *basep, *entryp, *sizep;
 
                 basep = of_get_flat_dt_prop(node, "linux,rtas-base", NULL);
                 entryp = of_get_flat_dt_prop(node, "linux,rtas-entry", NULL);
-                prop = of_get_flat_dt_prop(node, "linux,rtas-size", NULL);
-                if (basep && entryp && prop) {
+                sizep = of_get_flat_dt_prop(node, "linux,rtas-size", NULL);
+                if (basep && entryp && sizep) {
                         rtas.base = *basep;
                         rtas.entry = *entryp;
-                        rtas.size = *prop;
+                        rtas.size = *sizep;
                 }
         }
 #endif /* CONFIG_PPC_RTAS */
@@ -1775,7 +1797,7 @@ static int of_finish_dynamic_node(struct device_node *node)
         /* We don't support that function on PowerMac, at least
          * not yet
          */
-        if (_machine == PLATFORM_POWERMAC)
+        if (machine_is(powermac))
                 return -ENODEV;
 
         /* fix up new node's linux_phandle field */
diff --git a/arch/powerpc/kernel/prom_init.c b/arch/powerpc/kernel/prom_init.c
index 0d0887844501..d66c5e77fcff 100644
--- a/arch/powerpc/kernel/prom_init.c
+++ b/arch/powerpc/kernel/prom_init.c
@@ -180,6 +180,16 @@ static unsigned long __initdata prom_tce_alloc_start;
 static unsigned long __initdata prom_tce_alloc_end;
 #endif
 
+/* Platforms codes are now obsolete in the kernel. Now only used within this
+ * file and ultimately gone too. Feel free to change them if you need, they
+ * are not shared with anything outside of this file anymore
+ */
+#define PLATFORM_PSERIES        0x0100
+#define PLATFORM_PSERIES_LPAR   0x0101
+#define PLATFORM_LPAR           0x0001
+#define PLATFORM_POWERMAC       0x0400
+#define PLATFORM_GENERIC        0x0500
+
 static int __initdata of_platform;
 
 static char __initdata prom_cmd_line[COMMAND_LINE_SIZE];
@@ -1492,7 +1502,10 @@ static int __init prom_find_machine_type(void)
         int len, i = 0;
 #ifdef CONFIG_PPC64
         phandle rtas;
+        int x;
 #endif
+
+        /* Look for a PowerMac */
         len = prom_getprop(_prom->root, "compatible",
                            compat, sizeof(compat)-1);
         if (len > 0) {
@@ -1505,28 +1518,36 @@ static int __init prom_find_machine_type(void)
                         if (strstr(p, RELOC("Power Macintosh")) ||
                             strstr(p, RELOC("MacRISC")))
                                 return PLATFORM_POWERMAC;
-#ifdef CONFIG_PPC64
-                        if (strstr(p, RELOC("Momentum,Maple")))
-                                return PLATFORM_MAPLE;
-                        if (strstr(p, RELOC("IBM,CPB")))
-                                return PLATFORM_CELL;
-#endif
                         i += sl + 1;
                 }
         }
 #ifdef CONFIG_PPC64
+        /* If not a mac, try to figure out if it's an IBM pSeries or any other
+         * PAPR compliant platform. We assume it is if :
+         *  - /device_type is "chrp" (please, do NOT use that for future
+         *    non-IBM designs !
+         *  - it has /rtas
+         */
+        len = prom_getprop(_prom->root, "model",
+                           compat, sizeof(compat)-1);
+        if (len <= 0)
+                return PLATFORM_GENERIC;
+        compat[len] = 0;
+        if (strcmp(compat, "chrp"))
+                return PLATFORM_GENERIC;
+
         /* Default to pSeries. We need to know if we are running LPAR */
         rtas = call_prom("finddevice", 1, 1, ADDR("/rtas"));
-        if (PHANDLE_VALID(rtas)) {
-                int x = prom_getproplen(rtas, "ibm,hypertas-functions");
-                if (x != PROM_ERROR) {
-                        prom_printf("Hypertas detected, assuming LPAR !\n");
-                        return PLATFORM_PSERIES_LPAR;
-                }
+        if (!PHANDLE_VALID(rtas))
+                return PLATFORM_GENERIC;
+        x = prom_getproplen(rtas, "ibm,hypertas-functions");
+        if (x != PROM_ERROR) {
+                prom_printf("Hypertas detected, assuming LPAR !\n");
+                return PLATFORM_PSERIES_LPAR;
         }
         return PLATFORM_PSERIES;
 #else
-        return PLATFORM_CHRP;
+        return PLATFORM_GENERIC;
 #endif
 }
 
@@ -2034,7 +2055,6 @@ unsigned long __init prom_init(unsigned long r3, unsigned long r4,
 {       
         struct prom_t *_prom;
         unsigned long hdr;
-        u32 getprop_rval;
         unsigned long offset = reloc_offset();
 
 #ifdef CONFIG_PPC32
@@ -2070,9 +2090,6 @@ unsigned long __init prom_init(unsigned long r3, unsigned long r4,
          * between pSeries SMP and pSeries LPAR
          */
         RELOC(of_platform) = prom_find_machine_type();
-        getprop_rval = RELOC(of_platform);
-        prom_setprop(_prom->chosen, "/chosen", "linux,platform",
-                     &getprop_rval, sizeof(getprop_rval));
 
         /* Bail if this is a kdump kernel. */
         if (PHYSICAL_START > 0)
diff --git a/arch/powerpc/kernel/rtas-proc.c b/arch/powerpc/kernel/rtas-proc.c
index 1f03fb28cc0a..456286cf1d14 100644
--- a/arch/powerpc/kernel/rtas-proc.c
+++ b/arch/powerpc/kernel/rtas-proc.c
@@ -257,7 +257,7 @@ static int __init proc_rtas_init(void)
 {
         struct proc_dir_entry *entry;
 
-        if (_machine != PLATFORM_PSERIES && _machine != PLATFORM_PSERIES_LPAR)
+        if (!machine_is(pseries))
                 return 1;
 
         rtas_node = of_find_node_by_name(NULL, "rtas");
diff --git a/arch/powerpc/kernel/rtas.c b/arch/powerpc/kernel/rtas.c
index 142d818a31a6..4b78ee0e5867 100644
--- a/arch/powerpc/kernel/rtas.c
+++ b/arch/powerpc/kernel/rtas.c
@@ -25,6 +25,7 @@
 #include <asm/hvcall.h>
 #include <asm/semaphore.h>
 #include <asm/machdep.h>
+#include <asm/firmware.h>
 #include <asm/page.h>
 #include <asm/param.h>
 #include <asm/system.h>
@@ -768,7 +769,7 @@ void __init rtas_initialize(void)
          * the stop-self token if any
          */
 #ifdef CONFIG_PPC64
-        if (_machine == PLATFORM_PSERIES_LPAR) {
+        if (machine_is(pseries) && firmware_has_feature(FW_FEATURE_LPAR)) {
                 rtas_region = min(lmb.rmo_size, RTAS_INSTANTIATE_MAX);
                 ibm_suspend_me_token = rtas_token("ibm,suspend-me");
         }
diff --git a/arch/powerpc/kernel/setup-common.c b/arch/powerpc/kernel/setup-common.c
index b17630ad4ac7..3473cb9cb0ab 100644
--- a/arch/powerpc/kernel/setup-common.c
+++ b/arch/powerpc/kernel/setup-common.c
@@ -9,6 +9,9 @@
  *      as published by the Free Software Foundation; either version
  *      2 of the License, or (at your option) any later version.
  */
+
+#undef DEBUG
+
 #include <linux/config.h>
 #include <linux/module.h>
 #include <linux/string.h>
@@ -41,6 +44,7 @@
 #include <asm/time.h>
 #include <asm/cputable.h>
 #include <asm/sections.h>
+#include <asm/firmware.h>
 #include <asm/btext.h>
 #include <asm/nvram.h>
 #include <asm/setup.h>
@@ -56,8 +60,6 @@
 
 #include "setup.h"
 
-#undef DEBUG
-
 #ifdef DEBUG
 #include <asm/udbg.h>
 #define DBG(fmt...) udbg_printf(fmt)
@@ -65,10 +67,12 @@
 #define DBG(fmt...)
 #endif
 
-#ifdef CONFIG_PPC_MULTIPLATFORM
-int _machine = 0;
-EXPORT_SYMBOL(_machine);
-#endif
+/* The main machine-dep calls structure
+ */
+struct machdep_calls ppc_md;
+EXPORT_SYMBOL(ppc_md);
+struct machdep_calls *machine_id;
+EXPORT_SYMBOL(machine_id);
 
 unsigned long klimit = (unsigned long) _end;
 
@@ -168,7 +172,8 @@ static int show_cpuinfo(struct seq_file *m, void *v)
                            bogosum/(500000/HZ), bogosum/(5000/HZ) % 100);
 #endif /* CONFIG_SMP && CONFIG_PPC32 */
                 seq_printf(m, "timebase\t: %lu\n", ppc_tb_freq);
-
+                if (ppc_md.name)
+                        seq_printf(m, "platform\t: %s\n", ppc_md.name);
                 if (ppc_md.show_cpuinfo != NULL)
                         ppc_md.show_cpuinfo(m);
 
@@ -387,7 +392,7 @@ void __init smp_setup_cpu_maps(void)
          * On pSeries LPAR, we need to know how many cpus
          * could possibly be added to this partition.
          */
-        if (_machine == PLATFORM_PSERIES_LPAR &&
+        if (machine_is(pseries) && firmware_has_feature(FW_FEATURE_LPAR) &&
             (dn = of_find_node_by_path("/rtas"))) {
                 int num_addr_cell, num_size_cell, maxcpus;
                 unsigned int *ireg;
@@ -456,3 +461,34 @@ static int __init early_xmon(char *p)
 }
 early_param("xmon", early_xmon);
 #endif
+
+void probe_machine(void)
+{
+        extern struct machdep_calls __machine_desc_start;
+        extern struct machdep_calls __machine_desc_end;
+
+        /*
+         * Iterate all ppc_md structures until we find the proper
+         * one for the current machine type
+         */
+        DBG("Probing machine type ...\n");
+
+        for (machine_id = &__machine_desc_start;
+             machine_id < &__machine_desc_end;
+             machine_id++) {
+                DBG("  %s ...", machine_id->name);
+                memcpy(&ppc_md, machine_id, sizeof(struct machdep_calls));
+                if (ppc_md.probe()) {
+                        DBG(" match !\n");
+                        break;
+                }
+                DBG("\n");
+        }
+        /* What can we do if we didn't find ? */
+        if (machine_id >= &__machine_desc_end) {
+                DBG("No suitable machine found !\n");
+                for (;;);
+        }
+
+        printk(KERN_INFO "Using %s machine description\n", ppc_md.name);
+}
diff --git a/arch/powerpc/kernel/setup_32.c b/arch/powerpc/kernel/setup_32.c
index a2c89435abec..ae9c33d70731 100644
--- a/arch/powerpc/kernel/setup_32.c
+++ b/arch/powerpc/kernel/setup_32.c
@@ -67,10 +67,6 @@ unsigned int DMA_MODE_WRITE;
 int have_of = 1;
 
 #ifdef CONFIG_PPC_MULTIPLATFORM
-extern void prep_init(void);
-extern void pmac_init(void);
-extern void chrp_init(void);
-
 dev_t boot_dev;
 #endif /* CONFIG_PPC_MULTIPLATFORM */
 
@@ -82,9 +78,6 @@ unsigned long SYSRQ_KEY = 0x54;
 unsigned long vgacon_remap_base;
 #endif
 
-struct machdep_calls ppc_md;
-EXPORT_SYMBOL(ppc_md);
-
 /*
  * These are used in binfmt_elf.c to put aux entries on the stack
  * for each elf executable being started.
@@ -120,48 +113,6 @@ unsigned long __init early_init(unsigned long dt_ptr)
         return KERNELBASE + offset;
 }
 
-#ifdef CONFIG_PPC_MULTIPLATFORM
-/*
- * The PPC_MULTIPLATFORM version of platform_init...
- */
-void __init platform_init(void)
-{
-        /* if we didn't get any bootinfo telling us what we are... */
-        if (_machine == 0) {
-                /* prep boot loader tells us if we're prep or not */
-                if ( *(unsigned long *)(KERNELBASE) == (0xdeadc0de) )
-                        _machine = _MACH_prep;
-        }
-
-#ifdef CONFIG_PPC_PREP
-        /* not much more to do here, if prep */
-        if (_machine == _MACH_prep) {
-                prep_init();
-                return;
-        }
-#endif
-
-#ifdef CONFIG_ADB
-        if (strstr(cmd_line, "adb_sync")) {
-                extern int __adb_probe_sync;
-                __adb_probe_sync = 1;
-        }
-#endif /* CONFIG_ADB */
-
-        switch (_machine) {
-#ifdef CONFIG_PPC_PMAC
-        case _MACH_Pmac:
-                pmac_init();
-                break;
-#endif
-#ifdef CONFIG_PPC_CHRP
-        case _MACH_chrp:
-                chrp_init();
-                break;
-#endif
-        }
-}
-#endif
 
 /*
  * Find out what kind of machine we're on and save any data we need
@@ -187,8 +138,12 @@ void __init machine_init(unsigned long dt_ptr, unsigned long phys)
                 strlcpy(cmd_line, CONFIG_CMDLINE, sizeof(cmd_line));
 #endif /* CONFIG_CMDLINE */
 
-        /* Base init based on machine type */
+#ifdef CONFIG_PPC_MULTIPLATFORM
+        probe_machine();
+#else
+        /* Base init based on machine type. Obsoloete, please kill ! */
         platform_init();
+#endif
 
 #ifdef CONFIG_6xx
         if (cpu_has_feature(CPU_FTR_CAN_DOZE) ||
@@ -359,7 +314,4 @@ void __init setup_arch(char **cmdline_p)
         if ( ppc_md.progress ) ppc_md.progress("arch: exit", 0x3eab);
 
         paging_init();
-
-        /* this is for modules since _machine can be a define -- Cort */
-        ppc_md.ppc_machine = _machine;
 }
diff --git a/arch/powerpc/kernel/setup_64.c b/arch/powerpc/kernel/setup_64.c
index 5b63a861ef43..6aea1fb74b69 100644
--- a/arch/powerpc/kernel/setup_64.c
+++ b/arch/powerpc/kernel/setup_64.c
@@ -95,11 +95,6 @@ int dcache_bsize;
 int icache_bsize;
 int ucache_bsize;
 
-/* The main machine-dep calls structure
- */
-struct machdep_calls ppc_md;
-EXPORT_SYMBOL(ppc_md);
-
 #ifdef CONFIG_MAGIC_SYSRQ
 unsigned long SYSRQ_KEY;
 #endif /* CONFIG_MAGIC_SYSRQ */
@@ -160,32 +155,6 @@ early_param("smt-enabled", early_smt_enabled);
 #define check_smt_enabled()
 #endif /* CONFIG_SMP */
 
-extern struct machdep_calls pSeries_md;
-extern struct machdep_calls pmac_md;
-extern struct machdep_calls maple_md;
-extern struct machdep_calls cell_md;
-extern struct machdep_calls iseries_md;
-
-/* Ultimately, stuff them in an elf section like initcalls... */
-static struct machdep_calls __initdata *machines[] = {
-#ifdef CONFIG_PPC_PSERIES
-        &pSeries_md,
-#endif /* CONFIG_PPC_PSERIES */
-#ifdef CONFIG_PPC_PMAC
-        &pmac_md,
-#endif /* CONFIG_PPC_PMAC */
-#ifdef CONFIG_PPC_MAPLE
-        &maple_md,
-#endif /* CONFIG_PPC_MAPLE */
-#ifdef CONFIG_PPC_CELL
-        &cell_md,
-#endif
-#ifdef CONFIG_PPC_ISERIES
-        &iseries_md,
-#endif
-        NULL
-};
-
 /*
  * Early initialization entry point. This is called by head.S
  * with MMU translation disabled. We rely on the "feature" of
@@ -207,12 +176,10 @@ static struct machdep_calls __initdata *machines[] = {
 
 void __init early_setup(unsigned long dt_ptr)
 {
-        static struct machdep_calls **mach;
-
         /* Enable early debugging if any specified (see udbg.h) */
         udbg_early_init();
 
-        DBG(" -> early_setup()\n");
+        DBG(" -> early_setup(), dt_ptr: 0x%lx\n", dt_ptr);
 
         /*
          * Do early initializations using the flattened device
@@ -229,22 +196,8 @@ void __init early_setup(unsigned long dt_ptr)
         get_paca()->stab_real = __pa((u64)&initial_stab);
         get_paca()->stab_addr = (u64)&initial_stab;
 
-        /*
-         * Iterate all ppc_md structures until we find the proper
-         * one for the current machine type
-         */
-        DBG("Probing machine type for platform %x...\n", _machine);
-
-        for (mach = machines; *mach; mach++) {
-                if ((*mach)->probe(_machine))
-                        break;
-        }
-        /* What can we do if we didn't find ? */
-        if (*mach == NULL) {
-                DBG("No suitable machine found !\n");
-                for (;;);
-        }
-        ppc_md = **mach;
+        /* Probe the machine type */
+        probe_machine();
 
 #ifdef CONFIG_CRASH_DUMP
         kdump_setup();
@@ -346,7 +299,7 @@ static void __init initialize_cache_info(void)
                         const char *dc, *ic;
 
                         /* Then read cache informations */
-                        if (_machine == PLATFORM_POWERMAC) {
+                        if (machine_is(powermac)) {
                                 dc = "d-cache-block-size";
                                 ic = "i-cache-block-size";
                         } else {
@@ -490,7 +443,6 @@ void __init setup_system(void)
         printk("ppc64_pft_size                = 0x%lx\n", ppc64_pft_size);
         printk("ppc64_interrupt_controller    = 0x%ld\n",
                ppc64_interrupt_controller);
-        printk("platform                      = 0x%x\n", _machine);
         printk("physicalMemorySize            = 0x%lx\n", lmb_phys_mem_size());
         printk("ppc64_caches.dcache_line_size = 0x%x\n",
                ppc64_caches.dline_size);
diff --git a/arch/powerpc/kernel/traps.c b/arch/powerpc/kernel/traps.c
index 98660aedeeb7..27600c9432bc 100644
--- a/arch/powerpc/kernel/traps.c
+++ b/arch/powerpc/kernel/traps.c
@@ -97,7 +97,6 @@ static DEFINE_SPINLOCK(die_lock);
 int die(const char *str, struct pt_regs *regs, long err)
 {
         static int die_counter, crash_dump_start = 0;
-        int nl = 0;
 
         if (debugger(regs))
                 return 1;
@@ -106,7 +105,7 @@ int die(const char *str, struct pt_regs *regs, long err)
         spin_lock_irq(&die_lock);
         bust_spinlocks(1);
 #ifdef CONFIG_PMAC_BACKLIGHT
-        if (_machine == _MACH_Pmac) {
+        if (machine_is(powermac)) {
                 set_backlight_enable(1);
                 set_backlight_level(BACKLIGHT_MAX);
         }
@@ -114,46 +113,18 @@ int die(const char *str, struct pt_regs *regs, long err)
         printk("Oops: %s, sig: %ld [#%d]\n", str, err, ++die_counter);
 #ifdef CONFIG_PREEMPT
         printk("PREEMPT ");
-        nl = 1;
 #endif
 #ifdef CONFIG_SMP
         printk("SMP NR_CPUS=%d ", NR_CPUS);
-        nl = 1;
 #endif
 #ifdef CONFIG_DEBUG_PAGEALLOC
         printk("DEBUG_PAGEALLOC ");
-        nl = 1;
 #endif
 #ifdef CONFIG_NUMA
         printk("NUMA ");
-        nl = 1;
 #endif
-#ifdef CONFIG_PPC64
-        switch (_machine) {
-        case PLATFORM_PSERIES:
-                printk("PSERIES ");
-                nl = 1;
-                break;
-        case PLATFORM_PSERIES_LPAR:
-                printk("PSERIES LPAR ");
-                nl = 1;
-                break;
-        case PLATFORM_ISERIES_LPAR:
-                printk("ISERIES LPAR ");
-                nl = 1;
-                break;
-        case PLATFORM_POWERMAC:
-                printk("POWERMAC ");
-                nl = 1;
-                break;
-        case PLATFORM_CELL:
-                printk("CELL ");
-                nl = 1;
-                break;
-        }
-#endif
-        if (nl)
-                printk("\n");
+        printk("%s\n", ppc_md.name ? "" : ppc_md.name);
+
         print_modules();
         show_regs(regs);
         bust_spinlocks(0);
diff --git a/arch/powerpc/kernel/vdso.c b/arch/powerpc/kernel/vdso.c
index ec8370368423..573afb68d69e 100644
--- a/arch/powerpc/kernel/vdso.c
+++ b/arch/powerpc/kernel/vdso.c
@@ -33,6 +33,7 @@
 #include <asm/machdep.h>
 #include <asm/cputable.h>
 #include <asm/sections.h>
+#include <asm/firmware.h>
 #include <asm/vdso.h>
 #include <asm/vdso_datapage.h>
 
@@ -667,7 +668,13 @@ void __init vdso_init(void)
         vdso_data->version.major = SYSTEMCFG_MAJOR;
         vdso_data->version.minor = SYSTEMCFG_MINOR;
         vdso_data->processor = mfspr(SPRN_PVR);
-        vdso_data->platform = _machine;
+        /*
+         * Fake the old platform number for pSeries and iSeries and add
+         * in LPAR bit if necessary
+         */
+        vdso_data->platform = machine_is(iseries) ? 0x200 : 0x100;
+        if (firmware_has_feature(FW_FEATURE_LPAR))
+                vdso_data->platform |= 1;
         vdso_data->physicalMemorySize = lmb_phys_mem_size();
         vdso_data->dcache_size = ppc64_caches.dsize;
         vdso_data->dcache_line_size = ppc64_caches.dline_size;
diff --git a/arch/powerpc/kernel/vmlinux.lds.S b/arch/powerpc/kernel/vmlinux.lds.S
index 7fa7b15fd8e6..fe79c2584cb0 100644
--- a/arch/powerpc/kernel/vmlinux.lds.S
+++ b/arch/powerpc/kernel/vmlinux.lds.S
@@ -1,9 +1,11 @@
 #include <linux/config.h>
 #ifdef CONFIG_PPC64
 #include <asm/page.h>
+#define PROVIDE32(x)    PROVIDE(__unused__##x)
 #else
 #define PAGE_SIZE       4096
 #define KERNELBASE      CONFIG_KERNEL_START
+#define PROVIDE32(x)    PROVIDE(x)
 #endif
 #include <asm-generic/vmlinux.lds.h>
 
@@ -18,43 +20,42 @@ jiffies = jiffies_64 + 4;
 #endif
 SECTIONS
 {
-  /* Sections to be discarded. */
-  /DISCARD/ : {
-    *(.exitcall.exit)
-    *(.exit.data)
-  }
-
-  . = KERNELBASE;
-
-  /* Read-only sections, merged into text segment: */
-  .text : {
-    *(.text .text.*)
-    SCHED_TEXT
-    LOCK_TEXT
-    KPROBES_TEXT
-    *(.fixup)
-#ifdef CONFIG_PPC32
-    *(.got1)
-    __got2_start = .;
-    *(.got2)
-    __got2_end = .;
-#else
-    . = ALIGN(PAGE_SIZE);
-    _etext = .;
-#endif
-  }
-#ifdef CONFIG_PPC32
-  _etext = .;
-  PROVIDE (etext = .);
+        /* Sections to be discarded. */
+        /DISCARD/ : {
+        *(.exitcall.exit)
+        *(.exit.data)
+        }
 
-  RODATA
-  .fini      : { *(.fini)    } =0
-  .ctors     : { *(.ctors)   }
-  .dtors     : { *(.dtors)   }
+        . = KERNELBASE;
 
-  .fixup   : { *(.fixup) }
-#endif
+/*
+ * Text, read only data and other permanent read-only sections
+ */
+
+        /* Text and gots */
+        .text : {
+                *(.text .text.*)
+                SCHED_TEXT
+                LOCK_TEXT
+                KPROBES_TEXT
+                *(.fixup)
 
+#ifdef CONFIG_PPC32
+                *(.got1)
+                __got2_start = .;
+                *(.got2)
+                __got2_end = .;
+#endif /* CONFIG_PPC32 */
+
+                . = ALIGN(PAGE_SIZE);
+                _etext = .;
+                PROVIDE32 (etext = .);
+        }
+
+        /* Read-only data */
+        RODATA
+
+        /* Exception & bug tables */
         __ex_table : {
                 __start___ex_table = .;
                 *(__ex_table)
@@ -67,192 +68,172 @@ SECTIONS
                 __stop___bug_table = .;
         }
 
-#ifdef CONFIG_PPC64
+/*
+ * Init sections discarded at runtime
+ */
+        . = ALIGN(PAGE_SIZE);
+        __init_begin = .;
+
+        .init.text : {
+                _sinittext = .;
+                *(.init.text)
+                _einittext = .;
+        }
+
+        /* .exit.text is discarded at runtime, not link time,
+         * to deal with references from __bug_table
+         */
+        .exit.text : { *(.exit.text) }
+
+        .init.data : {
+                *(.init.data);
+                __vtop_table_begin = .;
+                *(.vtop_fixup);
+                __vtop_table_end = .;
+                __ptov_table_begin = .;
+                *(.ptov_fixup);
+                __ptov_table_end = .;
+        }
+
+        . = ALIGN(16);
+        .init.setup : {
+                __setup_start = .;
+                *(.init.setup)
+                __setup_end = .;
+        }
+
+        .initcall.init : {
+                __initcall_start = .;
+                *(.initcall1.init)
+                *(.initcall2.init)
+                *(.initcall3.init)
+                *(.initcall4.init)
+                *(.initcall5.init)
+                *(.initcall6.init)
+                *(.initcall7.init)
+                __initcall_end = .;
+                }
+
+        .con_initcall.init : {
+                __con_initcall_start = .;
+                *(.con_initcall.init)
+                __con_initcall_end = .;
+        }
+
+        SECURITY_INIT
+
+        . = ALIGN(8);
         __ftr_fixup : {
                 __start___ftr_fixup = .;
                 *(__ftr_fixup)
                 __stop___ftr_fixup = .;
         }
 
-  RODATA
-#endif
+        . = ALIGN(PAGE_SIZE);
+        .init.ramfs : {
+                __initramfs_start = .;
+                *(.init.ramfs)
+                __initramfs_end = .;
+        }
 
 #ifdef CONFIG_PPC32
-  /* Read-write section, merged into data segment: */
-  . = ALIGN(PAGE_SIZE);
-  _sdata = .;
-  .data    :
-  {
-    *(.data)
-    *(.data1)
-    *(.sdata)
-    *(.sdata2)
-    *(.got.plt) *(.got)
-    *(.dynamic)
-    CONSTRUCTORS
-  }
-
-  . = ALIGN(PAGE_SIZE);
-  __nosave_begin = .;
-  .data_nosave : { *(.data.nosave) }
-  . = ALIGN(PAGE_SIZE);
-  __nosave_end = .;
-
-  . = ALIGN(32);
-  .data.cacheline_aligned : { *(.data.cacheline_aligned) }
-
-  _edata  =  .;
-  PROVIDE (edata = .);
-
-  . = ALIGN(8192);
-  .data.init_task : { *(.data.init_task) }
+        . = ALIGN(32);
+#else
+        . = ALIGN(128);
 #endif
+        .data.percpu : {
+                __per_cpu_start = .;
+                *(.data.percpu)
+                __per_cpu_end = .;
+        }
 
-  /* will be freed after init */
-  . = ALIGN(PAGE_SIZE);
-  __init_begin = .;
-  .init.text : {
-        _sinittext = .;
-        *(.init.text)
-        _einittext = .;
-  }
-#ifdef CONFIG_PPC32
-  /* .exit.text is discarded at runtime, not link time,
-     to deal with references from __bug_table */
-  .exit.text : { *(.exit.text) }
-#endif
-  .init.data : {
-    *(.init.data);
-    __vtop_table_begin = .;
-    *(.vtop_fixup);
-    __vtop_table_end = .;
-    __ptov_table_begin = .;
-    *(.ptov_fixup);
-    __ptov_table_end = .;
-  }
-
-  . = ALIGN(16);
-  .init.setup : {
-    __setup_start = .;
-    *(.init.setup)
-    __setup_end = .;
-  }
-
-  .initcall.init : {
-        __initcall_start = .;
-        *(.initcall1.init)
-        *(.initcall2.init)
-        *(.initcall3.init)
-        *(.initcall4.init)
-        *(.initcall5.init)
-        *(.initcall6.init)
-        *(.initcall7.init)
-        __initcall_end = .;
-  }
-
-  .con_initcall.init : {
-    __con_initcall_start = .;
-    *(.con_initcall.init)
-    __con_initcall_end = .;
-  }
-
-  SECURITY_INIT
+        . = ALIGN(8);
+        .machine.desc : {
+                __machine_desc_start = . ;
+                *(.machine.desc)
+                __machine_desc_end = . ;
+        }
+
+        /* freed after init ends here */
+        . = ALIGN(PAGE_SIZE);
+        __init_end = .;
+
+/*
+ * And now the various read/write data
+ */
+
+        . = ALIGN(PAGE_SIZE);
+        _sdata = .;
 
 #ifdef CONFIG_PPC32
-  __start___ftr_fixup = .;
-  __ftr_fixup : { *(__ftr_fixup) }
-  __stop___ftr_fixup = .;
+        .data    :
+        {
+                *(.data)
+                *(.sdata)
+                *(.got.plt) *(.got)
+        }
 #else
-  . = ALIGN(PAGE_SIZE);
-  .init.ramfs : {
-    __initramfs_start = .;
-    *(.init.ramfs)
-    __initramfs_end = .;
-  }
-#endif
+        .data : {
+                *(.data .data.rel* .toc1)
+                *(.branch_lt)
+        }
 
-#ifdef CONFIG_PPC32
-  . = ALIGN(32);
+        .opd : {
+                *(.opd)
+        }
+
+        .got : {
+                __toc_start = .;
+                *(.got)
+                *(.toc)
+        }
 #endif
-  .data.percpu : {
-    __per_cpu_start = .;
-    *(.data.percpu)
-    __per_cpu_end = .;
-  }
 
- . = ALIGN(PAGE_SIZE);
-#ifdef CONFIG_PPC64
- . = ALIGN(16384);
- __init_end = .;
- /* freed after init ends here */
-
- /* Read/write sections */
- . = ALIGN(PAGE_SIZE);
- . = ALIGN(16384);
- _sdata = .;
- /* The initial task and kernel stack */
- .data.init_task : {
-      *(.data.init_task)
-      }
-
- . = ALIGN(PAGE_SIZE);
- .data.page_aligned : {
-      *(.data.page_aligned)
-      }
-
- .data.cacheline_aligned : {
-      *(.data.cacheline_aligned)
-      }
-
- .data : {
-      *(.data .data.rel* .toc1)
-      *(.branch_lt)
-      }
-
- .opd : {
-      *(.opd)
-      }
-
- .got : {
-      __toc_start = .;
-      *(.got)
-      *(.toc)
-      . = ALIGN(PAGE_SIZE);
-      _edata = .;
-      }
-
-  . = ALIGN(PAGE_SIZE);
+        . = ALIGN(PAGE_SIZE);
+        _edata  =  .;
+        PROVIDE32 (edata = .);
+
+        /* The initial task and kernel stack */
+#ifdef CONFIG_PPC32
+        . = ALIGN(8192);
 #else
-  __initramfs_start = .;
-  .init.ramfs : {
-    *(.init.ramfs)
-  }
-  __initramfs_end = .;
+        . = ALIGN(16384);
+#endif
+        .data.init_task : {
+                *(.data.init_task)
+        }
 
-  . = ALIGN(4096);
-  __init_end = .;
+        . = ALIGN(PAGE_SIZE);
+        .data.page_aligned : {
+                *(.data.page_aligned)
+        }
 
-  . = ALIGN(4096);
-  _sextratext = .;
-  _eextratext = .;
+        .data.cacheline_aligned : {
+                *(.data.cacheline_aligned)
+        }
 
-  __bss_start = .;
-#endif
+        . = ALIGN(PAGE_SIZE);
+        __data_nosave : {
+                __nosave_begin = .;
+                *(.data.nosave)
+                . = ALIGN(PAGE_SIZE);
+                __nosave_end = .;
+        }
 
-  .bss : {
-    __bss_start = .;
-   *(.sbss) *(.scommon)
-   *(.dynbss)
-   *(.bss)
-   *(COMMON)
-  __bss_stop = .;
-  }
+/*
+ * And finally the bss
+ */
+
+        .bss : {
+                __bss_start = .;
+                *(.sbss) *(.scommon)
+                *(.dynbss)
+                *(.bss)
+                *(COMMON)
+                __bss_stop = .;
+        }
 
-#ifdef CONFIG_PPC64
-  . = ALIGN(PAGE_SIZE);
-#endif
-  _end = . ;
-#ifdef CONFIG_PPC32
-  PROVIDE (end = .);
-#endif
+        . = ALIGN(PAGE_SIZE);
+        _end = . ;
+        PROVIDE32 (end = .);
 }
diff --git a/arch/powerpc/mm/hash_utils_64.c b/arch/powerpc/mm/hash_utils_64.c
index 89b35c181314..c006d9039633 100644
--- a/arch/powerpc/mm/hash_utils_64.c
+++ b/arch/powerpc/mm/hash_utils_64.c
@@ -167,7 +167,7 @@ int htab_bolt_mapping(unsigned long vstart, unsigned long vend,
                  * normal insert callback here.
                  */
 #ifdef CONFIG_PPC_ISERIES
-                if (_machine == PLATFORM_ISERIES_LPAR)
+                if (machine_is(iseries))
                         ret = iSeries_hpte_insert(hpteg, va,
                                                   paddr,
                                                   tmp_mode,
@@ -176,7 +176,7 @@ int htab_bolt_mapping(unsigned long vstart, unsigned long vend,
                 else
 #endif
 #ifdef CONFIG_PPC_PSERIES
-                if (_machine & PLATFORM_LPAR)
+                if (machine_is(pseries) && firmware_has_feature(FW_FEATURE_LPAR))
                         ret = pSeries_lpar_hpte_insert(hpteg, va,
                                                        paddr,
                                                        tmp_mode,
@@ -295,8 +295,7 @@ static void __init htab_init_page_sizes(void)
          * Not in the device-tree, let's fallback on known size
          * list for 16M capable GP & GR
          */
-        if ((_machine != PLATFORM_ISERIES_LPAR) &&
-            cpu_has_feature(CPU_FTR_16M_PAGE))
+        if (cpu_has_feature(CPU_FTR_16M_PAGE) && !machine_is(iseries))
                 memcpy(mmu_psize_defs, mmu_psize_defaults_gp,
                        sizeof(mmu_psize_defaults_gp));
  found:
diff --git a/arch/powerpc/platforms/cell/setup.c b/arch/powerpc/platforms/cell/setup.c
index fec8e65b36ea..dac5d0365fde 100644
--- a/arch/powerpc/platforms/cell/setup.c
+++ b/arch/powerpc/platforms/cell/setup.c
@@ -195,9 +195,13 @@ static void __init cell_init_early(void)
 }
 
 
-static int __init cell_probe(int platform)
+static int __init cell_probe(void)
 {
-        if (platform != PLATFORM_CELL)
+        /* XXX This is temporary, the Cell maintainer will come up with
+         * more appropriate detection logic
+         */
+        unsigned long root = of_get_flat_dt_root();
+        if (!of_flat_dt_is_compatible(root, "IBM,CPBW-1.0"))
                 return 0;
 
         return 1;
@@ -212,7 +216,8 @@ static int cell_check_legacy_ioport(unsigned int baseport)
         return -ENODEV;
 }
 
-struct machdep_calls __initdata cell_md = {
+define_machine(cell) {
+        .name                   = "Cell",
         .probe                  = cell_probe,
         .setup_arch             = cell_setup_arch,
         .init_early             = cell_init_early,
diff --git a/arch/powerpc/platforms/chrp/setup.c b/arch/powerpc/platforms/chrp/setup.c
index 9c718bb2305e..23a201718704 100644
--- a/arch/powerpc/platforms/chrp/setup.c
+++ b/arch/powerpc/platforms/chrp/setup.c
@@ -292,6 +292,10 @@ void __init chrp_setup_arch(void)
 
         pci_create_OF_bus_map();
 
+#ifdef CONFIG_SMP
+        smp_ops = &chrp_smp_ops;
+#endif /* CONFIG_SMP */
+
         /*
          * Print the banner, then scroll down so boot progress
          * can be printed.  -- Cort
@@ -506,8 +510,15 @@ chrp_init2(void)
                 ppc_md.progress("  Have fun!    ", 0x7777);
 }
 
-void __init chrp_init(void)
+static int __init chrp_probe(void)
 {
+        char *dtype = of_get_flat_dt_prop(of_get_flat_dt_root(),
+                                          "device_type", NULL);
+        if (dtype == NULL)
+                return 0;
+        if (strcmp(dtype, "chrp"))
+                return 0;
+
         ISA_DMA_THRESHOLD = ~0L;
         DMA_MODE_READ = 0x44;
         DMA_MODE_WRITE = 0x48;
diff --git a/arch/powerpc/platforms/iseries/setup.c b/arch/powerpc/platforms/iseries/setup.c
index 155aa690e4bb..6ce8a404ba6b 100644
--- a/arch/powerpc/platforms/iseries/setup.c
+++ b/arch/powerpc/platforms/iseries/setup.c
@@ -675,9 +675,10 @@ static void iseries_dedicated_idle(void)
 void __init iSeries_init_IRQ(void) { }
 #endif
 
-static int __init iseries_probe(int platform)
+static int __init iseries_probe(void)
 {
-        if (PLATFORM_ISERIES_LPAR != platform)
+        unsigned long root = of_get_flat_dt_root();
+        if (!of_flat_dt_is_compatible(root, "IBM,iSeries"))
                 return 0;
 
         powerpc_firmware_features |= FW_FEATURE_ISERIES;
@@ -686,7 +687,8 @@ static int __init iseries_probe(int platform)
         return 1;
 }
 
-struct machdep_calls __initdata iseries_md = {
+define_machine(iseries) {
+        .name           = "iSeries",
         .setup_arch     = iSeries_setup_arch,
         .show_cpuinfo   = iSeries_show_cpuinfo,
         .init_IRQ       = iSeries_init_IRQ,
@@ -930,7 +932,6 @@ void build_flat_dt(struct iseries_flat_dt *dt, unsigned long phys_mem_size)
 
         /* /chosen */
         dt_start_node(dt, "chosen");
-        dt_prop_u32(dt, "linux,platform", PLATFORM_ISERIES_LPAR);
         dt_prop_str(dt, "bootargs", cmd_line);
         if (cmd_mem_limit)
                 dt_prop_u64(dt, "linux,memory-limit", cmd_mem_limit);
diff --git a/arch/powerpc/platforms/maple/setup.c b/arch/powerpc/platforms/maple/setup.c
index 137d6063182b..24c0aef4ea39 100644
--- a/arch/powerpc/platforms/maple/setup.c
+++ b/arch/powerpc/platforms/maple/setup.c
@@ -259,9 +259,10 @@ static void __init maple_progress(char *s, unsigned short hex)
 /*
  * Called very early, MMU is off, device-tree isn't unflattened
  */
-static int __init maple_probe(int platform)
+static int __init maple_probe(void)
 {
-        if (platform != PLATFORM_MAPLE)
+        unsigned long root = of_get_flat_dt_root();
+        if (!of_flat_dt_is_compatible(root, "Momentum,Maple"))
                 return 0;
         /*
          * On U3, the DART (iommu) must be allocated now since it
@@ -274,7 +275,8 @@ static int __init maple_probe(int platform)
         return 1;
 }
 
-struct machdep_calls __initdata maple_md = {
+define_machine(maple_md) {
+        .name                   = "Maple",
         .probe                  = maple_probe,
         .setup_arch             = maple_setup_arch,
         .init_early             = maple_init_early,
diff --git a/arch/powerpc/platforms/powermac/bootx_init.c b/arch/powerpc/platforms/powermac/bootx_init.c
index a94571be65ca..eacbfd9beabc 100644
--- a/arch/powerpc/platforms/powermac/bootx_init.c
+++ b/arch/powerpc/platforms/powermac/bootx_init.c
@@ -161,9 +161,7 @@ static void __init bootx_dt_add_prop(char *name, void *data, int size,
 static void __init bootx_add_chosen_props(unsigned long base,
                                           unsigned long *mem_end)
 {
-        u32 val = _MACH_Pmac;
-
-        bootx_dt_add_prop("linux,platform", &val, 4, mem_end);
+        u32 val;
 
         if (bootx_info->kernelParamsOffset) {
                 char *args = (char *)((unsigned long)bootx_info) +
diff --git a/arch/powerpc/platforms/powermac/feature.c b/arch/powerpc/platforms/powermac/feature.c
index e49eddd5042d..a5063cd675c5 100644
--- a/arch/powerpc/platforms/powermac/feature.c
+++ b/arch/powerpc/platforms/powermac/feature.c
@@ -2951,7 +2951,7 @@ static void *pmac_early_vresume_data;
 
 void pmac_set_early_video_resume(void (*proc)(void *data), void *data)
 {
-        if (_machine != _MACH_Pmac)
+        if (!machine_is(powermac))
                 return;
         preempt_disable();
         pmac_early_vresume_proc = proc;
diff --git a/arch/powerpc/platforms/powermac/low_i2c.c b/arch/powerpc/platforms/powermac/low_i2c.c
index 87eb6bb7f0e7..e14f9ac55cf4 100644
--- a/arch/powerpc/platforms/powermac/low_i2c.c
+++ b/arch/powerpc/platforms/powermac/low_i2c.c
@@ -1457,6 +1457,9 @@ int __init pmac_i2c_init(void)
                 return 0;
         i2c_inited = 1;
 
+        if (!machine_is(powermac))
+                return 0;
+
         /* Probe keywest-i2c busses */
         kw_i2c_probe();
 
diff --git a/arch/powerpc/platforms/powermac/nvram.c b/arch/powerpc/platforms/powermac/nvram.c
index 3aa3477b86f7..262f967b880a 100644
--- a/arch/powerpc/platforms/powermac/nvram.c
+++ b/arch/powerpc/platforms/powermac/nvram.c
@@ -597,7 +597,7 @@ int __init pmac_nvram_init(void)
         }
 
 #ifdef CONFIG_PPC32
-        if (_machine == _MACH_chrp && nvram_naddrs == 1) {
+        if (machine_is(chrp) && nvram_naddrs == 1) {
                 nvram_data = ioremap(r1.start, s1);
                 nvram_mult = 1;
                 ppc_md.nvram_read_val   = direct_nvram_read_byte;
diff --git a/arch/powerpc/platforms/powermac/pci.c b/arch/powerpc/platforms/powermac/pci.c
index de3f30e6b333..f5d8d15d74fa 100644
--- a/arch/powerpc/platforms/powermac/pci.c
+++ b/arch/powerpc/platforms/powermac/pci.c
@@ -1201,7 +1201,7 @@ void __init pmac_pcibios_after_init(void)
 #ifdef CONFIG_PPC32
 void pmac_pci_fixup_cardbus(struct pci_dev* dev)
 {
-        if (_machine != _MACH_Pmac)
+        if (!machine_is(powermac))
                 return;
         /*
          * Fix the interrupt routing on the various cardbus bridges
@@ -1244,8 +1244,9 @@ void pmac_pci_fixup_pciata(struct pci_dev* dev)
         * On PowerMacs, we try to switch any PCI ATA controller to
         * fully native mode
         */
-        if (_machine != _MACH_Pmac)
+        if (!machine_is(powermac))
                 return;
+
         /* Some controllers don't have the class IDE */
         if (dev->vendor == PCI_VENDOR_ID_PROMISE)
                 switch(dev->device) {
diff --git a/arch/powerpc/platforms/powermac/pfunc_base.c b/arch/powerpc/platforms/powermac/pfunc_base.c
index 9b7150f10414..a3bd3e728fa3 100644
--- a/arch/powerpc/platforms/powermac/pfunc_base.c
+++ b/arch/powerpc/platforms/powermac/pfunc_base.c
@@ -336,6 +336,8 @@ int __init pmac_pfunc_base_install(void)
                 return 0;
         pfbase_inited = 1;
 
+        if (!machine_is(powermac))
+                return 0;
 
         DBG("Installing base platform functions...\n");
 
diff --git a/arch/powerpc/platforms/powermac/setup.c b/arch/powerpc/platforms/powermac/setup.c
index c2696d00672a..4d15e396655c 100644
--- a/arch/powerpc/platforms/powermac/setup.c
+++ b/arch/powerpc/platforms/powermac/setup.c
@@ -350,6 +350,13 @@ static void __init pmac_setup_arch(void)
                 smp_ops = &psurge_smp_ops;
 #endif
 #endif /* CONFIG_SMP */
+
+#ifdef CONFIG_ADB
+        if (strstr(cmd_line, "adb_sync")) {
+                extern int __adb_probe_sync;
+                __adb_probe_sync = 1;
+        }
+#endif /* CONFIG_ADB */
 }
 
 char *bootpath;
@@ -576,30 +583,6 @@ pmac_halt(void)
         pmac_power_off();
 }
 
-#ifdef CONFIG_PPC32
-void __init pmac_init(void)
-{
-        /* isa_io_base gets set in pmac_pci_init */
-        isa_mem_base = PMAC_ISA_MEM_BASE;
-        pci_dram_offset = PMAC_PCI_DRAM_OFFSET;
-        ISA_DMA_THRESHOLD = ~0L;
-        DMA_MODE_READ = 1;
-        DMA_MODE_WRITE = 2;
-
-        ppc_md = pmac_md;
-
-#if defined(CONFIG_BLK_DEV_IDE) || defined(CONFIG_BLK_DEV_IDE_MODULE)
-#ifdef CONFIG_BLK_DEV_IDE_PMAC
-        ppc_ide_md.ide_init_hwif        = pmac_ide_init_hwif_ports;
-        ppc_ide_md.default_io_base      = pmac_ide_get_base;
-#endif /* CONFIG_BLK_DEV_IDE_PMAC */
-#endif /* defined(CONFIG_BLK_DEV_IDE) || defined(CONFIG_BLK_DEV_IDE_MODULE) */
-
-        if (ppc_md.progress) ppc_md.progress("pmac_init(): exit", 0);
-
-}
-#endif
-
 /* 
  * Early initialization.
  */
@@ -646,6 +629,12 @@ static int __init pmac_declare_of_platform_devices(void)
 {
         struct device_node *np;
 
+        if (machine_is(chrp))
+                return -1;
+
+        if (!machine_is(powermac))
+                return 0;
+
         np = of_find_node_by_name(NULL, "valkyrie");
         if (np)
                 of_platform_device_create(np, "valkyrie", NULL);
@@ -666,12 +655,15 @@ device_initcall(pmac_declare_of_platform_devices);
 /*
  * Called very early, MMU is off, device-tree isn't unflattened
  */
-static int __init pmac_probe(int platform)
+static int __init pmac_probe(void)
 {
-#ifdef CONFIG_PPC64
-        if (platform != PLATFORM_POWERMAC)
+        unsigned long root = of_get_flat_dt_root();
+
+        if (!of_flat_dt_is_compatible(root, "Power Macintosh") &&
+            !of_flat_dt_is_compatible(root, "MacRISC"))
                 return 0;
 
+#ifdef CONFIG_PPC64
         /*
          * On U3, the DART (iommu) must be allocated now since it
          * has an impact on htab_initialize (due to the large page it
@@ -681,6 +673,23 @@ static int __init pmac_probe(int platform)
         alloc_dart_table();
 #endif
 
+#ifdef CONFIG_PPC32
+        /* isa_io_base gets set in pmac_pci_init */
+        isa_mem_base = PMAC_ISA_MEM_BASE;
+        pci_dram_offset = PMAC_PCI_DRAM_OFFSET;
+        ISA_DMA_THRESHOLD = ~0L;
+        DMA_MODE_READ = 1;
+        DMA_MODE_WRITE = 2;
+
+#if defined(CONFIG_BLK_DEV_IDE) || defined(CONFIG_BLK_DEV_IDE_MODULE)
+#ifdef CONFIG_BLK_DEV_IDE_PMAC
+        ppc_ide_md.ide_init_hwif        = pmac_ide_init_hwif_ports;
+        ppc_ide_md.default_io_base      = pmac_ide_get_base;
+#endif /* CONFIG_BLK_DEV_IDE_PMAC */
+#endif /* defined(CONFIG_BLK_DEV_IDE) || defined(CONFIG_BLK_DEV_IDE_MODULE) */
+
+#endif /* CONFIG_PPC32 */
+
 #ifdef CONFIG_PMAC_SMU
         /*
          * SMU based G5s need some memory below 2Gb, at least the current
@@ -709,10 +718,8 @@ static int pmac_pci_probe_mode(struct pci_bus *bus)
 }
 #endif
 
-struct machdep_calls __initdata pmac_md = {
-#if defined(CONFIG_HOTPLUG_CPU) && defined(CONFIG_PPC64)
-        .cpu_die                = generic_mach_cpu_die,
-#endif
+define_machine(powermac) {
+        .name                   = "PowerMac",
         .probe                  = pmac_probe,
         .setup_arch             = pmac_setup_arch,
         .init_early             = pmac_init_early,
@@ -746,4 +753,7 @@ struct machdep_calls __initdata pmac_md = {
         .pcibios_after_init     = pmac_pcibios_after_init,
         .phys_mem_access_prot   = pci_phys_mem_access_prot,
 #endif
+#if defined(CONFIG_HOTPLUG_CPU) && defined(CONFIG_PPC64)
+        .cpu_die                = generic_mach_cpu_die,
+#endif
 };
diff --git a/arch/powerpc/platforms/powermac/time.c b/arch/powerpc/platforms/powermac/time.c
index 5d9afa1fa02d..890758aa9667 100644
--- a/arch/powerpc/platforms/powermac/time.c
+++ b/arch/powerpc/platforms/powermac/time.c
@@ -336,10 +336,10 @@ static struct pmu_sleep_notifier time_sleep_notifier = {
  */
 void __init pmac_calibrate_decr(void)
 {
-#ifdef CONFIG_PM
+#if defined(CONFIG_PM) && defined(CONFIG_ADB_PMU)
         /* XXX why here? */
         pmu_register_sleep_notifier(&time_sleep_notifier);
-#endif /* CONFIG_PM */
+#endif
 
         generic_calibrate_decr();
 
diff --git a/arch/powerpc/platforms/pseries/eeh.c b/arch/powerpc/platforms/pseries/eeh.c
index 2ab9dcdfb415..9b2b1cb117b3 100644
--- a/arch/powerpc/platforms/pseries/eeh.c
+++ b/arch/powerpc/platforms/pseries/eeh.c
@@ -1018,7 +1018,7 @@ static int __init eeh_init_proc(void)
 {
         struct proc_dir_entry *e;
 
-        if (platform_is_pseries()) {
+        if (machine_is(pseries)) {
                 e = create_proc_entry("ppc64/eeh", 0, NULL);
                 if (e)
                         e->proc_fops = &proc_eeh_operations;
diff --git a/arch/powerpc/platforms/pseries/pci.c b/arch/powerpc/platforms/pseries/pci.c
index 946ad59e3352..e97e67f5e079 100644
--- a/arch/powerpc/platforms/pseries/pci.c
+++ b/arch/powerpc/platforms/pseries/pci.c
@@ -120,7 +120,7 @@ static void fixup_winbond_82c105(struct pci_dev* dev)
         int i;
         unsigned int reg;
 
-        if (!platform_is_pseries())
+        if (!machine_is(pseries))
                 return;
 
         printk("Using INTC for W82c105 IDE controller.\n");
diff --git a/arch/powerpc/platforms/pseries/pci_dlpar.c b/arch/powerpc/platforms/pseries/pci_dlpar.c
index b3c2dcb1e4f0..6bfacc217085 100644
--- a/arch/powerpc/platforms/pseries/pci_dlpar.c
+++ b/arch/powerpc/platforms/pseries/pci_dlpar.c
@@ -28,6 +28,7 @@
 #include <linux/pci.h>
 #include <asm/pci-bridge.h>
 #include <asm/ppc-pci.h>
+#include <asm/firmware.h>
 
 static struct pci_bus *
 find_bus_among_children(struct pci_bus *bus,
diff --git a/arch/powerpc/platforms/pseries/reconfig.c b/arch/powerpc/platforms/pseries/reconfig.c
index 86cfa6ecdcf3..9a4b592e40bc 100644
--- a/arch/powerpc/platforms/pseries/reconfig.c
+++ b/arch/powerpc/platforms/pseries/reconfig.c
@@ -17,8 +17,9 @@
 #include <linux/proc_fs.h>
 
 #include <asm/prom.h>
-#include <asm/pSeries_reconfig.h>
+#include <asm/machdep.h>
 #include <asm/uaccess.h>
+#include <asm/pSeries_reconfig.h>
 
 
 
@@ -508,7 +509,7 @@ static int proc_ppc64_create_ofdt(void)
 {
         struct proc_dir_entry *ent;
 
-        if (!platform_is_pseries())
+        if (!machine_is(pseries))
                 return 0;
 
         ent = create_proc_entry("ppc64/ofdt", S_IWUSR, NULL);
diff --git a/arch/powerpc/platforms/pseries/rtasd.c b/arch/powerpc/platforms/pseries/rtasd.c
index a6f628d4c9dc..fcc4d561a236 100644
--- a/arch/powerpc/platforms/pseries/rtasd.c
+++ b/arch/powerpc/platforms/pseries/rtasd.c
@@ -27,6 +27,7 @@
 #include <asm/prom.h>
 #include <asm/nvram.h>
 #include <asm/atomic.h>
+#include <asm/machdep.h>
 
 #if 0
 #define DEBUG(A...)     printk(KERN_ERR A)
@@ -481,7 +482,7 @@ static int __init rtas_init(void)
 {
         struct proc_dir_entry *entry;
 
-        if (!platform_is_pseries())
+        if (!machine_is(pseries))
                 return 0;
 
         /* No RTAS */
diff --git a/arch/powerpc/platforms/pseries/setup.c b/arch/powerpc/platforms/pseries/setup.c
index 1b0c4c034a26..b2fbf8ba8fbb 100644
--- a/arch/powerpc/platforms/pseries/setup.c
+++ b/arch/powerpc/platforms/pseries/setup.c
@@ -372,24 +372,42 @@ static int pSeries_check_legacy_ioport(unsigned int baseport)
 /*
  * Called very early, MMU is off, device-tree isn't unflattened
  */
-extern struct machdep_calls pSeries_md;
 
-static int __init pSeries_probe(int platform)
+static int __init pSeries_probe_hypertas(unsigned long node,
+                                         const char *uname, int depth,
+                                         void *data)
 {
-        if (platform != PLATFORM_PSERIES &&
-            platform != PLATFORM_PSERIES_LPAR)
+        if (depth != 1 ||
+            (strcmp(uname, "rtas") != 0 && strcmp(uname, "rtas@0") != 0))
+                return 0;
+
+        if (of_get_flat_dt_prop(node, "ibm,hypertas-functions", NULL) != NULL)
+                powerpc_firmware_features |= FW_FEATURE_LPAR;
+
+        return 1;
+}
+
+static int __init pSeries_probe(void)
+{
+        char *dtype = of_get_flat_dt_prop(of_get_flat_dt_root(),
+                                          "device_type", NULL);
+        if (dtype == NULL)
+                return 0;
+        if (strcmp(dtype, "chrp"))
                 return 0;
 
-        /* if we have some ppc_md fixups for LPAR to do, do
-         * it here ...
-         */
+        DBG("pSeries detected, looking for LPAR capability...\n");
 
-        if (platform == PLATFORM_PSERIES_LPAR)
-                powerpc_firmware_features |= FW_FEATURE_LPAR;
+        /* Now try to figure out if we are running on LPAR */
+        of_scan_flat_dt(pSeries_probe_hypertas, NULL);
+
+        DBG("Machine is%s LPAR !\n",
+            (powerpc_firmware_features & FW_FEATURE_LPAR) ? "" : " not");
 
         return 1;
 }
 
+
 DECLARE_PER_CPU(unsigned long, smt_snooze_delay);
 
 static void pseries_dedicated_idle_sleep(void)
@@ -501,7 +519,8 @@ static void pseries_kexec_cpu_down(int crash_shutdown, int secondary)
 }
 #endif
 
-struct machdep_calls __initdata pSeries_md = {
+define_machine(pseries) {
+        .name                   = "pSeries",
         .probe                  = pSeries_probe,
         .setup_arch             = pSeries_setup_arch,
         .init_early             = pSeries_init_early,
diff --git a/arch/ppc/platforms/prep_setup.c b/arch/ppc/platforms/prep_setup.c
index a0fc628ffb1e..fa46f8ce5c71 100644
--- a/arch/ppc/platforms/prep_setup.c
+++ b/arch/ppc/platforms/prep_setup.c
@@ -1067,15 +1067,13 @@ prep_map_io(void)
 static int __init
 prep_request_io(void)
 {
-        if (_machine == _MACH_prep) {
 #ifdef CONFIG_NVRAM
-                request_region(PREP_NVRAM_AS0, 0x8, "nvram");
+        request_region(PREP_NVRAM_AS0, 0x8, "nvram");
 #endif
-                request_region(0x00,0x20,"dma1");
-                request_region(0x40,0x20,"timer");
-                request_region(0x80,0x10,"dma page reg");
-                request_region(0xc0,0x20,"dma2");
-        }
+        request_region(0x00,0x20,"dma1");
+        request_region(0x40,0x20,"timer");
+        request_region(0x80,0x10,"dma page reg");
+        request_region(0xc0,0x20,"dma2");
 
         return 0;
 }
diff --git a/drivers/char/generic_nvram.c b/drivers/char/generic_nvram.c
index 1b5e01e6e129..43ff59816511 100644
--- a/drivers/char/generic_nvram.c
+++ b/drivers/char/generic_nvram.c
@@ -22,6 +22,9 @@
 #include <linux/smp_lock.h>
 #include <asm/uaccess.h>
 #include <asm/nvram.h>
+#ifdef CONFIG_PPC_PMAC
+#include <asm/machdep.h>
+#endif
 
 #define NVRAM_SIZE      8192
 
@@ -92,7 +95,7 @@ static int nvram_ioctl(struct inode *inode, struct file *file,
         case IOC_NVRAM_GET_OFFSET: {
                 int part, offset;
 
-                if (_machine != _MACH_Pmac)
+                if (!machine_is(powermac))
                         return -EINVAL;
                 if (copy_from_user(&part, (void __user*)arg, sizeof(part)) != 0)
                         return -EFAULT;
diff --git a/drivers/ide/pci/via82cxxx.c b/drivers/ide/pci/via82cxxx.c
index c85b87cb59d1..3e677c4f8c28 100644
--- a/drivers/ide/pci/via82cxxx.c
+++ b/drivers/ide/pci/via82cxxx.c
@@ -440,7 +440,7 @@ static void __devinit init_hwif_via82cxxx(ide_hwif_t *hwif)
 
 
 #if defined(CONFIG_PPC_CHRP) && defined(CONFIG_PPC32)
-        if(_machine == _MACH_chrp && _chrp_type == _CHRP_Pegasos) {
+        if(machine_is(chrp) && _chrp_type == _CHRP_Pegasos) {
                 hwif->irq = hwif->channel ? 15 : 14;
         }
 #endif
diff --git a/drivers/ide/ppc/pmac.c b/drivers/ide/ppc/pmac.c
index 5013b1285e22..78e30f803671 100644
--- a/drivers/ide/ppc/pmac.c
+++ b/drivers/ide/ppc/pmac.c
@@ -1677,7 +1677,7 @@ MODULE_DEVICE_TABLE(pci, pmac_ide_pci_match);
 void __init
 pmac_ide_probe(void)
 {
-        if (_machine != _MACH_Pmac)
+        if (!machine_is(powermac))
                 return;
 
 #ifdef CONFIG_BLK_DEV_IDE_PMAC_ATA100FIRST
diff --git a/drivers/ieee1394/ohci1394.c b/drivers/ieee1394/ohci1394.c
index b6b96fa04d62..314f35540034 100644
--- a/drivers/ieee1394/ohci1394.c
+++ b/drivers/ieee1394/ohci1394.c
@@ -3526,7 +3526,7 @@ static void ohci1394_pci_remove(struct pci_dev *pdev)
 static int ohci1394_pci_resume (struct pci_dev *pdev)
 {
 #ifdef CONFIG_PPC_PMAC
-        if (_machine == _MACH_Pmac) {
+        if (machine_is(powermac)) {
                 struct device_node *of_node;
 
                 /* Re-enable 1394 */
@@ -3545,7 +3545,7 @@ static int ohci1394_pci_resume (struct pci_dev *pdev)
 static int ohci1394_pci_suspend (struct pci_dev *pdev, pm_message_t state)
 {
 #ifdef CONFIG_PPC_PMAC
-        if (_machine == _MACH_Pmac) {
+        if (machine_is(powermac)) {
                 struct device_node *of_node;
 
                 /* Disable 1394 */
diff --git a/drivers/macintosh/adb.c b/drivers/macintosh/adb.c
index d2ead1776c16..781d93b0bbd5 100644
--- a/drivers/macintosh/adb.c
+++ b/drivers/macintosh/adb.c
@@ -42,6 +42,7 @@
 #include <asm/semaphore.h>
 #ifdef CONFIG_PPC
 #include <asm/prom.h>
+#include <asm/machdep.h>
 #endif
 
 
@@ -294,7 +295,7 @@ int __init adb_init(void)
         int i;
 
 #ifdef CONFIG_PPC32
-        if ( (_machine != _MACH_chrp) && (_machine != _MACH_Pmac) )
+        if (!machine_is(chrp) && !machine_is(powermac))
                 return 0;
 #endif
 #ifdef CONFIG_MAC
diff --git a/drivers/macintosh/adbhid.c b/drivers/macintosh/adbhid.c
index c0b46bceb5df..0a4c680d4ac0 100644
--- a/drivers/macintosh/adbhid.c
+++ b/drivers/macintosh/adbhid.c
@@ -1206,8 +1206,8 @@ init_ms_a3(int id)
 static int __init adbhid_init(void)
 {
 #ifndef CONFIG_MAC
-        if ( (_machine != _MACH_chrp) && (_machine != _MACH_Pmac) )
-            return 0;
+        if (!machine_is(chrp) && !machine_is(powermac))
+                return 0;
 #endif
 
         led_request.complete = 1;
diff --git a/drivers/macintosh/mediabay.c b/drivers/macintosh/mediabay.c
index 8dbf2852bae0..53c1c7909413 100644
--- a/drivers/macintosh/mediabay.c
+++ b/drivers/macintosh/mediabay.c
@@ -839,8 +839,8 @@ static int __init media_bay_init(void)
                 media_bays[i].cd_index          = -1;
 #endif
         }
-        if (_machine != _MACH_Pmac)
-                return -ENODEV;
+        if (!machine_is(powermac))
+                return 0;
 
         macio_register_driver(&media_bay_driver);       
 
diff --git a/drivers/media/video/planb.c b/drivers/media/video/planb.c
index 522e9ddeb089..d9e3cada52f4 100644
--- a/drivers/media/video/planb.c
+++ b/drivers/media/video/planb.c
@@ -2156,7 +2156,7 @@ static int find_planb(void)
         struct pci_dev          *pdev;
         int rc;
 
-        if (_machine != _MACH_Pmac)
+        if (!machine_is(powermac))
                 return 0;
 
         planb_devices = find_devices("planb");
diff --git a/drivers/net/tulip/de4x5.c b/drivers/net/tulip/de4x5.c
index ee48bfd67349..46d087c5467b 100644
--- a/drivers/net/tulip/de4x5.c
+++ b/drivers/net/tulip/de4x5.c
@@ -4160,7 +4160,7 @@ get_hw_addr(struct net_device *dev)
     ** If the address starts with 00 a0, we have to bit-reverse
     ** each byte of the address.
     */
-    if ( (_machine & _MACH_Pmac) &&
+    if ( machine_is(powermac) &&
          (dev->dev_addr[0] == 0) &&
          (dev->dev_addr[1] == 0xa0) )
     {
diff --git a/drivers/scsi/mesh.c b/drivers/scsi/mesh.c
index d6d2125f9044..f852421002ef 100644
--- a/drivers/scsi/mesh.c
+++ b/drivers/scsi/mesh.c
@@ -1748,7 +1748,7 @@ static int mesh_host_reset(struct scsi_cmnd *cmd)
 
 static void set_mesh_power(struct mesh_state *ms, int state)
 {
-        if (_machine != _MACH_Pmac)
+        if (!machine_is(powermac))
                 return;
         if (state) {
                 pmac_call_feature(PMAC_FTR_MESH_ENABLE, macio_get_of_node(ms->mdev), 0, 1);
diff --git a/drivers/usb/core/hcd-pci.c b/drivers/usb/core/hcd-pci.c
index e0afb5ad29e5..0d2193b69235 100644
--- a/drivers/usb/core/hcd-pci.c
+++ b/drivers/usb/core/hcd-pci.c
@@ -296,7 +296,7 @@ done:
 
 #ifdef CONFIG_PPC_PMAC
                 /* Disable ASIC clocks for USB */
-                if (_machine == _MACH_Pmac) {
+                if (machine_is(powermac)) {
                         struct device_node      *of_node;
 
                         of_node = pci_device_to_OF_node (dev);
@@ -331,7 +331,7 @@ int usb_hcd_pci_resume (struct pci_dev *dev)
 
 #ifdef CONFIG_PPC_PMAC
         /* Reenable ASIC clocks for USB */
-        if (_machine == _MACH_Pmac) {
+        if (machine_is(powermac)) {
                 struct device_node *of_node;
 
                 of_node = pci_device_to_OF_node (dev);
diff --git a/drivers/video/aty/aty128fb.c b/drivers/video/aty/aty128fb.c
index 620c9a934e0e..f07be22e119d 100644
--- a/drivers/video/aty/aty128fb.c
+++ b/drivers/video/aty/aty128fb.c
@@ -67,6 +67,7 @@
 #include <asm/io.h>
 
 #ifdef CONFIG_PPC_PMAC
+#include <asm/machdep.h>
 #include <asm/pmac_feature.h>
 #include <asm/prom.h>
 #include <asm/pci-bridge.h>
@@ -1748,7 +1749,7 @@ static int __init aty128_init(struct pci_dev *pdev, const struct pci_device_id *
 
         var = default_var;
 #ifdef CONFIG_PPC_PMAC
-        if (_machine == _MACH_Pmac) {
+        if (machine_is(powermac)) {
                 /* Indicate sleep capability */
                 if (par->chip_gen == rage_M3) {
                         pmac_call_feature(PMAC_FTR_DEVICE_CAN_WAKE, NULL, 0, 1);
@@ -2011,7 +2012,7 @@ static int aty128fb_blank(int blank, struct fb_info *fb)
                 return 0;
 
 #ifdef CONFIG_PMAC_BACKLIGHT
-        if ((_machine == _MACH_Pmac) && blank)
+        if (machine_is(powermac) && blank)
                 set_backlight_enable(0);
 #endif /* CONFIG_PMAC_BACKLIGHT */
 
@@ -2029,7 +2030,7 @@ static int aty128fb_blank(int blank, struct fb_info *fb)
                 aty128_set_lcd_enable(par, par->lcd_on && !blank);
         }
 #ifdef CONFIG_PMAC_BACKLIGHT
-        if ((_machine == _MACH_Pmac) && !blank)
+        if (machine_is(powermac) && !blank)
                 set_backlight_enable(1);
 #endif /* CONFIG_PMAC_BACKLIGHT */
         return 0;
diff --git a/drivers/video/aty/atyfb_base.c b/drivers/video/aty/atyfb_base.c
index 485be386a8ff..1b1f24e2bfbe 100644
--- a/drivers/video/aty/atyfb_base.c
+++ b/drivers/video/aty/atyfb_base.c
@@ -75,6 +75,7 @@
 #include "ati_ids.h"
 
 #ifdef __powerpc__
+#include <asm/machdep.h>
 #include <asm/prom.h>
 #include "../macmodes.h"
 #endif
@@ -2516,7 +2517,7 @@ static int __init aty_init(struct fb_info *info, const char *name)
 
         memset(&var, 0, sizeof(var));
 #ifdef CONFIG_PPC
-        if (_machine == _MACH_Pmac) {
+        if (machine_is(powermac)) {
                 /*
                  *  FIXME: The NVRAM stuff should be put in a Mac-specific file, as it
                  *         applies to all Mac video cards
@@ -2671,7 +2672,7 @@ static int atyfb_blank(int blank, struct fb_info *info)
                 return 0;
 
 #ifdef CONFIG_PMAC_BACKLIGHT
-        if ((_machine == _MACH_Pmac) && blank > FB_BLANK_NORMAL)
+        if (machine_is(powermac) && blank > FB_BLANK_NORMAL)
                 set_backlight_enable(0);
 #elif defined(CONFIG_FB_ATY_GENERIC_LCD)
         if (par->lcd_table && blank > FB_BLANK_NORMAL &&
@@ -2703,7 +2704,7 @@ static int atyfb_blank(int blank, struct fb_info *info)
         aty_st_le32(CRTC_GEN_CNTL, gen_cntl, par);
 
 #ifdef CONFIG_PMAC_BACKLIGHT
-        if ((_machine == _MACH_Pmac) && blank <= FB_BLANK_NORMAL)
+        if (machine_is(powermac) && blank <= FB_BLANK_NORMAL)
                 set_backlight_enable(1);
 #elif defined(CONFIG_FB_ATY_GENERIC_LCD)
         if (par->lcd_table && blank <= FB_BLANK_NORMAL &&
diff --git a/drivers/video/aty/radeon_pm.c b/drivers/video/aty/radeon_pm.c
index 5886a2f1323e..c7091761cef4 100644
--- a/drivers/video/aty/radeon_pm.c
+++ b/drivers/video/aty/radeon_pm.c
@@ -20,7 +20,7 @@
 #include <linux/agp_backend.h>
 
 #ifdef CONFIG_PPC_PMAC
-#include <asm/processor.h>
+#include <asm/machdep.h>
 #include <asm/prom.h>
 #include <asm/pmac_feature.h>
 #endif
@@ -2745,7 +2745,7 @@ void radeonfb_pm_init(struct radeonfb_info *rinfo, int dynclk)
                 rinfo->pm_mode |= radeon_pm_off;
         }
 #if defined(CONFIG_PPC_PMAC)
-        if (_machine == _MACH_Pmac && rinfo->of_node) {
+        if (machine_is(powermac) && rinfo->of_node) {
                 if (rinfo->is_mobility && rinfo->pm_reg &&
                     rinfo->family <= CHIP_FAMILY_RV250)
                         rinfo->pm_mode |= radeon_pm_d2;
diff --git a/drivers/video/cirrusfb.c b/drivers/video/cirrusfb.c
index 66d6f2f0a219..1103010af54a 100644
--- a/drivers/video/cirrusfb.c
+++ b/drivers/video/cirrusfb.c
@@ -60,8 +60,8 @@
 #include <asm/amigahw.h>
 #endif
 #ifdef CONFIG_PPC_PREP
-#include <asm/processor.h>
-#define isPReP (_machine == _MACH_prep)
+#include <asm/machdep.h>
+#define isPReP (machine_is(prep))
 #else
 #define isPReP 0
 #endif
diff --git a/drivers/video/matrox/matroxfb_base.c b/drivers/video/matrox/matroxfb_base.c
index 951c9974a1d3..23c1827b2d0b 100644
--- a/drivers/video/matrox/matroxfb_base.c
+++ b/drivers/video/matrox/matroxfb_base.c
@@ -115,6 +115,7 @@
 #include <asm/uaccess.h>
 
 #ifdef CONFIG_PPC_PMAC
+#include <asm/machdep.h>
 unsigned char nvram_read_byte(int);
 static int default_vmode = VMODE_NVRAM;
 static int default_cmode = CMODE_NVRAM;
@@ -1833,7 +1834,7 @@ static int initMatrox2(WPMINFO struct board* b){
         /* FIXME: Where to move this?! */
 #if defined(CONFIG_PPC_PMAC)
 #ifndef MODULE
-        if (_machine == _MACH_Pmac) {
+        if (machine_is(powermac)) {
                 struct fb_var_screeninfo var;
                 if (default_vmode <= 0 || default_vmode > VMODE_MAX)
                         default_vmode = VMODE_640_480_60;
diff --git a/drivers/video/nvidia/nvidia.c b/drivers/video/nvidia/nvidia.c
index a7c4e5e8ead6..7258b3245316 100644
--- a/drivers/video/nvidia/nvidia.c
+++ b/drivers/video/nvidia/nvidia.c
@@ -29,6 +29,7 @@
 #include <asm/pci-bridge.h>
 #endif
 #ifdef CONFIG_PMAC_BACKLIGHT
+#include <asm/machdep.h>
 #include <asm/backlight.h>
 #endif
 
@@ -1353,7 +1354,7 @@ static int nvidiafb_blank(int blank, struct fb_info *info)
         NVWriteCrtc(par, 0x1a, vesa);
 
 #ifdef CONFIG_PMAC_BACKLIGHT
-        if (par->FlatPanel && _machine == _MACH_Pmac) {
+        if (par->FlatPanel && machine_is(powermac)) {
                 set_backlight_enable(!blank);
         }
 #endif
@@ -1688,7 +1689,7 @@ static int __devinit nvidiafb_probe(struct pci_dev *pd,
                info->fix.id,
                par->FbMapSize / (1024 * 1024), info->fix.smem_start);
 #ifdef CONFIG_PMAC_BACKLIGHT
-        if (par->FlatPanel && _machine == _MACH_Pmac)
+        if (par->FlatPanel && machine_is(powermac))
                 register_backlight_controller(&nvidia_backlight_controller,
                                               par, "mnca");
 #endif
diff --git a/drivers/video/radeonfb.c b/drivers/video/radeonfb.c
index db9fb9074dbc..04820fab964c 100644
--- a/drivers/video/radeonfb.c
+++ b/drivers/video/radeonfb.c
@@ -1596,7 +1596,7 @@ static int radeonfb_blank (int blank, struct fb_info *info)
                 return 0;
                 
 #ifdef CONFIG_PMAC_BACKLIGHT
-        if (rinfo->dviDisp_type == MT_LCD && _machine == _MACH_Pmac) {
+        if (rinfo->dviDisp_type == MT_LCD && machine_is(powermac)) {
                 set_backlight_enable(!blank);
                 return 0;
         }
diff --git a/drivers/video/riva/fbdev.c b/drivers/video/riva/fbdev.c
index 6c19ab6afb01..b7bd6bb2c77c 100644
--- a/drivers/video/riva/fbdev.c
+++ b/drivers/video/riva/fbdev.c
@@ -49,6 +49,7 @@
 #include <asm/pci-bridge.h>
 #endif
 #ifdef CONFIG_PMAC_BACKLIGHT
+#include <asm/machdep.h>
 #include <asm/backlight.h>
 #endif
 
@@ -1247,7 +1248,7 @@ static int rivafb_blank(int blank, struct fb_info *info)
         CRTCout(par, 0x1a, vesa);
 
 #ifdef CONFIG_PMAC_BACKLIGHT
-        if ( par->FlatPanel && _machine == _MACH_Pmac) {
+        if ( par->FlatPanel && machine_is(powermac)) {
                 set_backlight_enable(!blank);
         }
 #endif
@@ -2037,9 +2038,9 @@ static int __devinit rivafb_probe(struct pci_dev *pd,
                 info->fix.smem_len / (1024 * 1024),
                 info->fix.smem_start);
 #ifdef CONFIG_PMAC_BACKLIGHT
-        if (default_par->FlatPanel && _machine == _MACH_Pmac)
-        register_backlight_controller(&riva_backlight_controller,
-                                                default_par, "mnca");
+        if (default_par->FlatPanel && machine_is(powermac))
+                register_backlight_controller(&riva_backlight_controller,
+                                              default_par, "mnca");
 #endif
         NVTRACE_LEAVE();
         return 0;
diff --git a/fs/partitions/mac.c b/fs/partitions/mac.c
index bb22cdd0cb14..813292f21210 100644
--- a/fs/partitions/mac.c
+++ b/fs/partitions/mac.c
@@ -12,6 +12,7 @@
 #include "mac.h"
 
 #ifdef CONFIG_PPC_PMAC
+#include <asm/machdep.h>
 extern void note_bootable_part(dev_t dev, int part, int goodness);
 #endif
 
@@ -79,7 +80,7 @@ int mac_partition(struct parsed_partitions *state, struct block_device *bdev)
                  * If this is the first bootable partition, tell the
                  * setup code, in case it wants to make this the root.
                  */
-                if (_machine == _MACH_Pmac) {
+                if (machine_is(powermac)) {
                         int goodness = 0;
 
                         mac_fix_string(part->processor, 16);
diff --git a/include/asm-powerpc/machdep.h b/include/asm-powerpc/machdep.h
index 758e47fe8c1e..5ed847680754 100644
--- a/include/asm-powerpc/machdep.h
+++ b/include/asm-powerpc/machdep.h
@@ -47,6 +47,7 @@ struct smp_ops_t {
 #endif
 
 struct machdep_calls {
+        char            *name;
 #ifdef CONFIG_PPC64
         void            (*hpte_invalidate)(unsigned long slot,
                                            unsigned long va,
@@ -85,9 +86,9 @@ struct machdep_calls {
         void            (*iommu_dev_setup)(struct pci_dev *dev);
         void            (*iommu_bus_setup)(struct pci_bus *bus);
         void            (*irq_bus_setup)(struct pci_bus *bus);
-#endif
+#endif /* CONFIG_PPC64 */
 
-        int             (*probe)(int platform);
+        int             (*probe)(void);
         void            (*setup_arch)(void);
         void            (*init_early)(void);
         /* Optional, may be NULL. */
@@ -207,8 +208,6 @@ struct machdep_calls {
         /* Called at then very end of pcibios_init() */
         void (*pcibios_after_init)(void);
 
-        /* this is for modules, since _machine can be a define -- Cort */
-        int ppc_machine;
 #endif /* CONFIG_PPC32 */
 
         /* Called to shutdown machine specific hardware not already controlled
@@ -244,7 +243,26 @@ struct machdep_calls {
 extern void power4_idle(void);
 extern void ppc6xx_idle(void);
 
+/*
+ * ppc_md contains a copy of the machine description structure for the
+ * current platform. machine_id contains the initial address where the
+ * description was found during boot.
+ */
 extern struct machdep_calls ppc_md;
+extern struct machdep_calls *machine_id;
+
+#define __machine_desc __attribute__ ((__section__ (".machine.desc")))
+
+#define define_machine(name) struct machdep_calls mach_##name __machine_desc =
+#define machine_is(name) \
+        ({ \
+                extern struct machdep_calls mach_##name \
+                        __attribute__((weak));           \
+                machine_id == &mach_##name; \
+        })
+
+extern void probe_machine(void);
+
 extern char cmd_line[COMMAND_LINE_SIZE];
 
 #ifdef CONFIG_PPC_PMAC
diff --git a/include/asm-powerpc/pmac_feature.h b/include/asm-powerpc/pmac_feature.h
index 3221628130c4..d3599cc9aa74 100644
--- a/include/asm-powerpc/pmac_feature.h
+++ b/include/asm-powerpc/pmac_feature.h
@@ -305,7 +305,7 @@ extern void pmac_feature_init(void);
 extern void pmac_set_early_video_resume(void (*proc)(void *data), void *data);
 extern void pmac_call_early_video_resume(void);
 
-#define PMAC_FTR_DEF(x) ((_MACH_Pmac << 16) | (x))
+#define PMAC_FTR_DEF(x) ((0x6660000) | (x))
 
 /* The AGP driver registers itself here */
 extern void pmac_register_agp_pm(struct pci_dev *bridge,
diff --git a/include/asm-powerpc/processor.h b/include/asm-powerpc/processor.h
index 57643b5b782f..93f83efeb310 100644
--- a/include/asm-powerpc/processor.h
+++ b/include/asm-powerpc/processor.h
@@ -22,22 +22,6 @@
  * -- BenH.
  */
 
-/* Platforms codes (to be obsoleted) */
-#define PLATFORM_PSERIES        0x0100
-#define PLATFORM_PSERIES_LPAR   0x0101
-#define PLATFORM_ISERIES_LPAR   0x0201
-#define PLATFORM_LPAR           0x0001
-#define PLATFORM_POWERMAC       0x0400
-#define PLATFORM_MAPLE          0x0500
-#define PLATFORM_PREP           0x0600
-#define PLATFORM_CHRP           0x0700
-#define PLATFORM_CELL           0x1000
-
-/* Compat platform codes for 32 bits */
-#define _MACH_prep      PLATFORM_PREP
-#define _MACH_Pmac      PLATFORM_POWERMAC
-#define _MACH_chrp      PLATFORM_CHRP
-
 /* PREP sub-platform types see residual.h for these */
 #define _PREP_Motorola  0x01    /* motorola prep */
 #define _PREP_Firm      0x02    /* firmworks prep */
@@ -49,15 +33,14 @@
 #define _CHRP_IBM       0x05    /* IBM chrp, the longtrail and longtrail 2 */
 #define _CHRP_Pegasos   0x06    /* Genesi/bplan's Pegasos and Pegasos2 */
 
-#ifdef __KERNEL__
-#define platform_is_pseries()   (_machine == PLATFORM_PSERIES || \
-                                 _machine == PLATFORM_PSERIES_LPAR)
+#if defined(__KERNEL__) && defined(CONFIG_PPC32)
+
+extern int _chrp_type;
 
 #ifdef CONFIG_PPC_PREP
 
 /* what kind of prep workstation we are */
 extern int _prep_type;
-extern int _chrp_type;
 
 /*
  * This is used to identify the board type from a given PReP board
@@ -69,18 +52,12 @@ extern unsigned char ucBoardRevMaj, ucBoardRevMin;
 
 #endif /* CONFIG_PPC_PREP */
 
-#if defined(CONFIG_PPC_MULTIPLATFORM)
-extern int _machine;
-
-#elif defined(CONFIG_PPC_ISERIES)
-/*
- * iSeries is soon to become MULTIPLATFORM hopefully ...
- */
-#define _machine PLATFORM_ISERIES_LPAR
-#else
+#ifndef CONFIG_PPC_MULTIPLATFORM
 #define _machine 0
 #endif /* CONFIG_PPC_MULTIPLATFORM */
-#endif /* __KERNEL__ */
+
+#endif /* defined(__KERNEL__) && defined(CONFIG_PPC32) */
+
 /*
  * Default implementation of macro that returns current
  * instruction pointer ("program counter").
diff --git a/include/asm-powerpc/prom.h b/include/asm-powerpc/prom.h
index 782e13a070a1..97ef1cd71a4d 100644
--- a/include/asm-powerpc/prom.h
+++ b/include/asm-powerpc/prom.h
@@ -149,12 +149,14 @@ extern struct device_node *of_node_get(struct device_node *node);
 extern void of_node_put(struct device_node *node);
 
 /* For scanning the flat device-tree at boot time */
-int __init of_scan_flat_dt(int (*it)(unsigned long node,
-                                     const char *uname, int depth,
-                                     void *data),
-                           void *data);
-void* __init of_get_flat_dt_prop(unsigned long node, const char *name,
-                                 unsigned long *size);
+extern int __init of_scan_flat_dt(int (*it)(unsigned long node,
+                                            const char *uname, int depth,
+                                            void *data),
+                                  void *data);
+extern void* __init of_get_flat_dt_prop(unsigned long node, const char *name,
+                                        unsigned long *size);
+extern int __init of_flat_dt_is_compatible(unsigned long node, const char *name);
+extern unsigned long __init of_get_flat_dt_root(void);
 
 /* For updating the device tree at runtime */
 extern void of_attach_node(struct device_node *);
diff --git a/include/asm-powerpc/vdso_datapage.h b/include/asm-powerpc/vdso_datapage.h
index 7aa92086c3fb..8a94f0eba5e9 100644
--- a/include/asm-powerpc/vdso_datapage.h
+++ b/include/asm-powerpc/vdso_datapage.h
@@ -55,6 +55,9 @@ struct vdso_data {
                 __u32 minor;            /* Minor number                 0x14 */
         } version;
 
+        /* Note about the platform flags: it now only contains the lpar
+         * bit. The actual platform number is dead and burried
+         */
         __u32 platform;                 /* Platform flags               0x18 */
         __u32 processor;                /* Processor type               0x1C */
         __u64 processorCount;           /* # of physical processors     0x20 */
diff --git a/include/asm-ppc/machdep.h b/include/asm-ppc/machdep.h
index 2723b423f675..e1a0a7b213d7 100644
--- a/include/asm-ppc/machdep.h
+++ b/include/asm-ppc/machdep.h
@@ -19,6 +19,18 @@ struct pci_dev;
 struct seq_file;
 struct file;
 
+/*
+ * This is for compatibility with ARCH=powerpc.
+ */
+#define machine_is(x)   __MACHINE_IS_##x
+#define __MACHINE_IS_powermac   0
+#define __MACHINE_IS_chrp       0
+#ifdef CONFIG_PPC_PREP
+#define __MACHINE_IS_prep       1
+#else
+#define __MACHINE_IS_prep       0
+#endif
+
 /* We export this macro for external modules like Alsa to know if
  * ppc_md.feature_call is implemented or not
  */
diff --git a/sound/oss/dmasound/dmasound_awacs.c b/sound/oss/dmasound/dmasound_awacs.c
index 6ba8d6f45fe8..a8636adef2e6 100644
--- a/sound/oss/dmasound/dmasound_awacs.c
+++ b/sound/oss/dmasound/dmasound_awacs.c
@@ -2814,7 +2814,7 @@ int __init dmasound_awacs_init(void)
         struct device_node *io = NULL, *info = NULL;
         int vol, res;
 
-        if (_machine != _MACH_Pmac)
+        if (!machine_is(powermac))
                 return -ENODEV;
 
         awacs_subframe = 0;
diff --git a/sound/ppc/pmac.c b/sound/ppc/pmac.c
index aa57170101fd..f0794ef9d1ac 100644
--- a/sound/ppc/pmac.c
+++ b/sound/ppc/pmac.c
@@ -869,7 +869,7 @@ static int __init snd_pmac_detect(struct snd_pmac *chip)
 
         u32 layout_id = 0;
 
-        if (_machine != _MACH_Pmac)
+        if (!machine_is(powermac))
                 return -ENODEV;
 
         chip->subframe = 0;