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authorScott Wood <scottwood@freescale.com>2011-07-25 11:29:33 +0000
committerBenjamin Herrenschmidt <benh@kernel.crashing.org>2011-09-20 09:19:47 +1000
commit6dece0eb69b2a28e18d104bc5d707f1cb673f5e0 (patch)
treea5f3fcffc289d71cb31152e7d07f14da49607643 /arch/powerpc/kernel/head_fsl_booke.S
parent6c493685f1b209dd4ae41eb52c818cf12da20def (diff)
downloadlwn-6dece0eb69b2a28e18d104bc5d707f1cb673f5e0.tar.gz
lwn-6dece0eb69b2a28e18d104bc5d707f1cb673f5e0.zip
powerpc/32: Pass device tree address as u64 to machine_init
u64 is used rather than phys_addr_t to keep things simple, as this is called from assembly code. Update callers to pass a 64-bit address in r3/r4. Other unused register assignments that were once parameters to machine_init are dropped. For FSL BookE, look up the physical address of the device tree from the effective address passed in r3 by the loader. This is required for situations where memory does not start at zero (due to AMP or IOMMU-less virtualization), and thus the IMA doesn't start at zero, and thus the device tree effective address does not equal the physical address. Signed-off-by: Scott Wood <scottwood@freescale.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Diffstat (limited to 'arch/powerpc/kernel/head_fsl_booke.S')
-rw-r--r--arch/powerpc/kernel/head_fsl_booke.S42
1 files changed, 26 insertions, 16 deletions
diff --git a/arch/powerpc/kernel/head_fsl_booke.S b/arch/powerpc/kernel/head_fsl_booke.S
index 4ea9bfbf67e9..e1c699f3b7a7 100644
--- a/arch/powerpc/kernel/head_fsl_booke.S
+++ b/arch/powerpc/kernel/head_fsl_booke.S
@@ -63,17 +63,30 @@ _ENTRY(_start);
* of abatron_pteptrs
*/
nop
-/*
- * Save parameters we are passed
- */
- mr r31,r3
- mr r30,r4
- mr r29,r5
- mr r28,r6
- mr r27,r7
- li r25,0 /* phys kernel start (low) */
- li r24,0 /* CPU number */
- li r23,0 /* phys kernel start (high) */
+
+ /* Translate device tree address to physical, save in r30/r31 */
+ mfmsr r16
+ mfspr r17,SPRN_PID
+ rlwinm r17,r17,16,0x3fff0000 /* turn PID into MAS6[SPID] */
+ rlwimi r17,r16,28,0x00000001 /* turn MSR[DS] into MAS6[SAS] */
+ mtspr SPRN_MAS6,r17
+
+ tlbsx 0,r3 /* must succeed */
+
+ mfspr r16,SPRN_MAS1
+ mfspr r20,SPRN_MAS3
+ rlwinm r17,r16,25,0x1f /* r17 = log2(page size) */
+ li r18,1024
+ slw r18,r18,r17 /* r18 = page size */
+ addi r18,r18,-1
+ and r19,r3,r18 /* r19 = page offset */
+ andc r31,r20,r18 /* r3 = page base */
+ or r31,r31,r19 /* r3 = devtree phys addr */
+ mfspr r30,SPRN_MAS7
+
+ li r25,0 /* phys kernel start (low) */
+ li r24,0 /* CPU number */
+ li r23,0 /* phys kernel start (high) */
/* We try to not make any assumptions about how the boot loader
* setup or used the TLBs. We invalidate all mappings from the
@@ -198,11 +211,8 @@ _ENTRY(__early_start)
/*
* Decide what sort of machine this is and initialize the MMU.
*/
- mr r3,r31
- mr r4,r30
- mr r5,r29
- mr r6,r28
- mr r7,r27
+ mr r3,r30
+ mr r4,r31
bl machine_init
bl MMU_init