[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>

1 files changed, 22 insertions, 4 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