[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>

6 files changed, 53 insertions, 41 deletions

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
  */