powerpc/kconfig: Kill PPC_MULTIPLATFORM

CONFIG_PPC_MULTIPLATFORM is a remain of the pre-powerpc days and isn't
really meaningful anymore. It was basically equivalent to PPC64 || 6xx.

This removes it along with the following changes:

 - 32-bit platforms that relied on PPC32 && PPC_MULTIPLATFORM now rely
   on 6xx which is what they want anyway.

 - A new symbol, PPC_BOOK3S, is defined that represent compliance with
   the "Server" variant of the architecture. This is set when either 6xx
   or PPC64 is set and open the door for future BOOK3E 64-bit.

 - 64-bit platforms that relied on PPC64 && PPC_MULTIPLATFORM now use
   PPC64 && PPC_BOOK3S

 - A separate and selectable CONFIG_PPC_OF_BOOT_TRAMPOLINE option is now
   used to control the use of prom_init.c

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

3 files changed, 11 insertions, 4 deletions

diff --git a/arch/powerpc/kernel/Makefile b/arch/powerpc/kernel/Makefile
index dfec3d2790b2..71901fbda4a5 100644
--- a/arch/powerpc/kernel/Makefile
+++ b/arch/powerpc/kernel/Makefile
@@ -75,7 +75,7 @@ obj-y				+= time.o prom.o traps.o setup-common.o \
 obj-$(CONFIG_PPC32)             += entry_32.o setup_32.o
 obj-$(CONFIG_PPC64)             += dma-iommu.o iommu.o
 obj-$(CONFIG_KGDB)              += kgdb.o
-obj-$(CONFIG_PPC_MULTIPLATFORM) += prom_init.o
+obj-$(CONFIG_PPC_OF_BOOT_TRAMPOLINE)    += prom_init.o
 obj-$(CONFIG_MODULES)           += ppc_ksyms.o
 obj-$(CONFIG_BOOTX_TEXT)        += btext.o
 obj-$(CONFIG_SMP)               += smp.o
diff --git a/arch/powerpc/kernel/head_32.S b/arch/powerpc/kernel/head_32.S
index a1c4cfd25ded..f8c2e6b6f457 100644
--- a/arch/powerpc/kernel/head_32.S
+++ b/arch/powerpc/kernel/head_32.S
@@ -108,18 +108,21 @@ __start:
  * because OF may have I/O devices mapped into that area
  * (particularly on CHRP).
  */
-#ifdef CONFIG_PPC_MULTIPLATFORM
         cmpwi   0,r5,0
         beq     1f
 
+#ifdef CONFIG_PPC_OF_BOOT_TRAMPOLINE
         /* find out where we are now */
         bcl     20,31,$+4
 0:      mflr    r8                      /* r8 = runtime addr here */
         addis   r8,r8,(_stext - 0b)@ha
         addi    r8,r8,(_stext - 0b)@l   /* current runtime base addr */
         bl      prom_init
+#endif /* CONFIG_PPC_OF_BOOT_TRAMPOLINE */
+
+        /* We never return. We also hit that trap if trying to boot
+         * from OF while CONFIG_PPC_OF_BOOT_TRAMPOLINE isn't selected */
         trap
-#endif
 
 /*
  * Check for BootX signature when supporting PowerMac and branch to
diff --git a/arch/powerpc/kernel/head_64.S b/arch/powerpc/kernel/head_64.S
index ebaedafc8e67..50ef505b8fb6 100644
--- a/arch/powerpc/kernel/head_64.S
+++ b/arch/powerpc/kernel/head_64.S
@@ -1360,6 +1360,7 @@ _GLOBAL(__start_initialization_multiplatform)
         b       .__after_prom_start
 
 _INIT_STATIC(__boot_from_prom)
+#ifdef CONFIG_PPC_OF_BOOT_TRAMPOLINE
         /* Save parameters */
         mr      r31,r3
         mr      r30,r4
@@ -1390,7 +1391,10 @@ _INIT_STATIC(__boot_from_prom)
         /* Do all of the interaction with OF client interface */
         mr      r8,r26
         bl      .prom_init
-        /* We never return */
+#endif /* #CONFIG_PPC_OF_BOOT_TRAMPOLINE */
+
+        /* We never return. We also hit that trap if trying to boot
+         * from OF while CONFIG_PPC_OF_BOOT_TRAMPOLINE isn't selected */
         trap
 
 _STATIC(__after_prom_start)