powerpc: Run on old powermacs.

Old powermacs have a number of differences from current machines:
- there is no interrupt tree in the device tree, just interrupt
  or AAPL,interrupt properties
- the chosen node in the device tree is called /chosen@0
- the OF claim method doesn't map the memory, so we have to do
  an explicit map call as well
- there is no /chosen/cpu property on SMP machines
- the NVRAM isn't structured as a set of partitions.

This adapts the merged powermac support code to cope with these
issues.

Signed-off-by: Paul Mackerras <paulus@samba.org>

1 files changed, 63 insertions, 24 deletions

diff --git a/arch/powerpc/kernel/prom_init.c b/arch/powerpc/kernel/prom_init.c
index 095659d51b4b..18d266d8935d 100644
--- a/arch/powerpc/kernel/prom_init.c
+++ b/arch/powerpc/kernel/prom_init.c
@@ -132,6 +132,7 @@ struct prom_t {
         ihandle chosen;
         int cpu;
         ihandle stdout;
+        ihandle mmumap;
 };
 
 struct mem_map_entry {
@@ -274,14 +275,6 @@ static int __init call_prom_ret(const char *service, int nargs, int nret,
 }
 
 
-static unsigned int __init prom_claim(unsigned long virt, unsigned long size,
-                                unsigned long align)
-{
-        return (unsigned int)call_prom("claim", 3, 1,
-                                       (prom_arg_t)virt, (prom_arg_t)size,
-                                       (prom_arg_t)align);
-}
-
 static void __init prom_print(const char *msg)
 {
         const char *p, *q;
@@ -363,6 +356,21 @@ static void __init prom_printf(const char *format, ...)
 }
 
 
+static unsigned int __init prom_claim(unsigned long virt, unsigned long size,
+                                unsigned long align)
+{
+        int ret;
+        struct prom_t *_prom = &RELOC(prom);
+
+        ret = call_prom("claim", 3, 1, (prom_arg_t)virt, (prom_arg_t)size,
+                        (prom_arg_t)align);
+        if (ret != -1 && _prom->mmumap != 0)
+                /* old pmacs need us to map as well */
+                call_prom("call-method", 6, 1,
+                          ADDR("map"), _prom->mmumap, 0, size, virt, virt);
+        return ret;
+}
+
 static void __init __attribute__((noreturn)) prom_panic(const char *reason)
 {
 #ifdef CONFIG_PPC64
@@ -1323,7 +1331,37 @@ static void __init prom_init_client_services(unsigned long pp)
         _prom->root = call_prom("finddevice", 1, 1, ADDR("/"));
         if (!PHANDLE_VALID(_prom->root))
                 prom_panic("cannot find device tree root"); /* msg won't be printed :( */
+
+        _prom->mmumap = 0;
+}
+
+#ifdef CONFIG_PPC32
+/*
+ * For really old powermacs, we need to map things we claim.
+ * For that, we need the ihandle of the mmu.
+ */
+static void __init prom_find_mmu(void)
+{
+        struct prom_t *_prom = &RELOC(prom);
+        phandle oprom;
+        char version[64];
+
+        oprom = call_prom("finddevice", 1, 1, ADDR("/openprom"));
+        if (!PHANDLE_VALID(oprom))
+                return;
+        if (prom_getprop(oprom, "model", version, sizeof(version)) <= 0)
+                return;
+        version[sizeof(version) - 1] = 0;
+        prom_printf("OF version is '%s'\n", version);
+        /* XXX might need to add other versions here */
+        if (strcmp(version, "Open Firmware, 1.0.5") != 0)
+                return;
+        prom_getprop(_prom->chosen, "mmu", &_prom->mmumap,
+                     sizeof(_prom->mmumap));
 }
+#else
+#define prom_find_mmu()
+#endif
 
 static void __init prom_init_stdout(void)
 {
@@ -1379,7 +1417,7 @@ static int __init prom_find_machine_type(void)
                         if (sl == 0)
                                 break;
                         if (strstr(p, RELOC("Power Macintosh")) ||
-                            strstr(p, RELOC("MacRISC4")))
+                            strstr(p, RELOC("MacRISC")))
                                 return PLATFORM_POWERMAC;
 #ifdef CONFIG_PPC64
                         if (strstr(p, RELOC("Momentum,Maple")))
@@ -1618,22 +1656,17 @@ static void __init scan_dt_build_struct(phandle node, unsigned long *mem_start,
                 namep[l] = '\0';
 
                 /* Fixup an Apple bug where they have bogus \0 chars in the
-                 * middle of the path in some properties
+                 * middle of the path in some properties, and extract
+                 * the unit name (everything after the last '/').
                  */
-                for (p = namep, ep = namep + l; p < ep; p++)
-                        if (*p == '\0') {
-                                memmove(p, p+1, ep - p);
-                                ep--; l--; p--;
-                        }
-
-                /* now try to extract the unit name in that mess */
-                for (p = namep, lp = NULL; *p; p++)
+                for (lp = p = namep, ep = namep + l; p < ep; p++) {
                         if (*p == '/')
-                                lp = p + 1;
-                if (lp != NULL)
-                        memmove(namep, lp, strlen(lp) + 1);
-                *mem_start = _ALIGN(((unsigned long) namep) +
-                                    strlen(namep) + 1, 4);
+                                lp = namep;
+                        else if (*p != 0)
+                                *lp++ = *p;
+                }
+                *lp = 0;
+                *mem_start = _ALIGN((unsigned long)lp + 1, 4);
         }
 
         /* get it again for debugging */
@@ -1858,8 +1891,9 @@ static void __init prom_find_boot_cpu(void)
         ihandle prom_cpu;
         phandle cpu_pkg;
 
+        _prom->cpu = 0;
         if (prom_getprop(_prom->chosen, "cpu", &prom_cpu, sizeof(prom_cpu)) <= 0)
-                prom_panic("cannot find boot cpu");
+                return;
 
         cpu_pkg = call_prom("instance-to-package", 1, 1, prom_cpu);
 
@@ -1934,6 +1968,11 @@ unsigned long __init prom_init(unsigned long r3, unsigned long r4,
         prom_init_stdout();
 
         /*
+         * See if this OF is old enough that we need to do explicit maps
+         */
+        prom_find_mmu();
+
+        /*
          * Check for an initrd
          */
         prom_check_initrd(r3, r4);