[POWERPC] 85xx: Respect KERNELBASE, PAGE_OFFSET, and PHYSICAL_START on e500

The e500 MMU init code previously assumed KERNELBASE always equaled
PAGE_OFFSET and PHYSICAL_START was 0.  This is useful for kdump
support as well as asymetric multicore.

For the initial kdump support the secondary kernel will run at 32M
but need access to all of memory so we bump the initial TLB up to
64M.  This also matches with the forth coming ePAPR spec.

Signed-off-by: Dale Farnsworth <dale@farnsworth.org>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
diff --git a/arch/powerpc/kernel/head_fsl_booke.S b/arch/powerpc/kernel/head_fsl_booke.S
index 7aecb39..d9cc2c2 100644
--- a/arch/powerpc/kernel/head_fsl_booke.S
+++ b/arch/powerpc/kernel/head_fsl_booke.S
@@ -73,8 +73,8 @@
 /* We try to not make any assumptions about how the boot loader
  * setup or used the TLBs.  We invalidate all mappings from the
  * boot loader and load a single entry in TLB1[0] to map the
- * first 16M of kernel memory.  Any boot info passed from the
- * bootloader needs to live in this first 16M.
+ * first 64M of kernel memory.  Any boot info passed from the
+ * bootloader needs to live in this first 64M.
  *
  * Requirement on bootloader:
  *  - The page we're executing in needs to reside in TLB1 and
@@ -167,7 +167,7 @@
 	mtspr	SPRN_MAS0,r7
 	tlbre
 
-	/* Just modify the entry ID and EPN for the temp mapping */
+	/* Just modify the entry ID, EPN and RPN for the temp mapping */
 	lis	r7,0x1000	/* Set MAS0(TLBSEL) = 1 */
 	rlwimi	r7,r5,16,4,15	/* Setup MAS0 = TLBSEL | ESEL(r5) */
 	mtspr	SPRN_MAS0,r7
@@ -177,9 +177,12 @@
 	ori	r6,r6,(MAS1_TSIZE(BOOKE_PAGESZ_4K))@l
 	mtspr	SPRN_MAS1,r6
 	mfspr	r6,SPRN_MAS2
-	li	r7,0		/* temp EPN = 0 */
+	lis	r7,PHYSICAL_START@h
 	rlwimi	r7,r6,0,20,31
 	mtspr	SPRN_MAS2,r7
+	mfspr	r6,SPRN_MAS3
+	rlwimi	r7,r6,0,20,31
+	mtspr	SPRN_MAS3,r7
 	tlbwe
 
 	xori	r6,r4,1
@@ -222,11 +225,11 @@
 	lis	r6,0x1000		/* Set MAS0(TLBSEL) = TLB1(1), ESEL = 0 */
 	mtspr	SPRN_MAS0,r6
 	lis	r6,(MAS1_VALID|MAS1_IPROT)@h
-	ori	r6,r6,(MAS1_TSIZE(BOOKE_PAGESZ_16M))@l
+	ori	r6,r6,(MAS1_TSIZE(BOOKE_PAGESZ_64M))@l
 	mtspr	SPRN_MAS1,r6
 	li	r7,0
-	lis	r6,KERNELBASE@h
-	ori	r6,r6,KERNELBASE@l
+	lis	r6,PAGE_OFFSET@h
+	ori	r6,r6,PAGE_OFFSET@l
 	rlwimi	r6,r7,0,20,31
 	mtspr	SPRN_MAS2,r6
 	li	r7,(MAS3_SX|MAS3_SW|MAS3_SR)
@@ -234,6 +237,9 @@
 	tlbwe
 
 /* 7. Jump to KERNELBASE mapping */
+	lis	r6,KERNELBASE@h
+	ori	r6,r6,KERNELBASE@l
+	rlwimi	r6,r7,0,20,31
 	lis	r7,MSR_KERNEL@h
 	ori	r7,r7,MSR_KERNEL@l
 	bl	1f			/* Find our address */