This is based on the codes in the head_44x.S. Since we always align to
256M before mapping the PAGE_OFFSET for a relocatable kernel, we also
change the init tlb map to 256M size.
Signed-off-by: Kevin Hao <haoke...@gmail.com>
---
v2: Move the code to set kernstart_addr and virt_phys_offset to a c function.
So we can expand it easily later.
Hi Scott,
I still use the 256M align for the init tlb as in v1 for the following reasons:
* This should be the most possible case in reality.
* This is just for very early booting code and should not be a big issue
if the first tlb entry shrink to a less size later.
arch/powerpc/Kconfig | 2 +-
arch/powerpc/kernel/fsl_booke_entry_mapping.S | 8 +++---
arch/powerpc/kernel/head_fsl_booke.S | 37 +++++++++++++++++++++++++++
arch/powerpc/mm/fsl_booke_mmu.c | 28 ++++++++++++++++++++
4 files changed, 71 insertions(+), 4 deletions(-)
diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
index 5374776..5b2e115 100644
--- a/arch/powerpc/Kconfig
+++ b/arch/powerpc/Kconfig
@@ -859,7 +859,7 @@ config DYNAMIC_MEMSTART
config RELOCATABLE
bool "Build a relocatable kernel"
- depends on ADVANCED_OPTIONS && FLATMEM && 44x
+ depends on ADVANCED_OPTIONS && FLATMEM && (44x || FSL_BOOKE)
select NONSTATIC_KERNEL
help
This builds a kernel image that is capable of running at the
diff --git a/arch/powerpc/kernel/fsl_booke_entry_mapping.S
b/arch/powerpc/kernel/fsl_booke_entry_mapping.S
index 2201f84..211e507 100644
--- a/arch/powerpc/kernel/fsl_booke_entry_mapping.S
+++ b/arch/powerpc/kernel/fsl_booke_entry_mapping.S
@@ -167,10 +167,10 @@ ALT_MMU_FTR_SECTION_END_IFSET(MMU_FTR_BIG_PHYS)
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(BOOK3E_PAGESZ_64M))@l
+ ori r6,r6,(MAS1_TSIZE(BOOK3E_PAGESZ_256M))@l
mtspr SPRN_MAS1,r6
- lis r6,MAS2_VAL(PAGE_OFFSET, BOOK3E_PAGESZ_64M, M_IF_SMP)@h
- ori r6,r6,MAS2_VAL(PAGE_OFFSET, BOOK3E_PAGESZ_64M, M_IF_SMP)@l
+ lis r6,MAS2_VAL(PAGE_OFFSET, BOOK3E_PAGESZ_256M, M_IF_SMP)@h
+ ori r6,r6,MAS2_VAL(PAGE_OFFSET, BOOK3E_PAGESZ_256M, M_IF_SMP)@l
mtspr SPRN_MAS2,r6
mtspr SPRN_MAS3,r8
tlbwe
@@ -178,6 +178,8 @@ ALT_MMU_FTR_SECTION_END_IFSET(MMU_FTR_BIG_PHYS)
/* 7. Jump to KERNELBASE mapping */
lis r6,(KERNELBASE & ~0xfff)@h
ori r6,r6,(KERNELBASE & ~0xfff)@l
+ rlwinm r7,r25,0,0x0fffffff
+ add r6,r7,r6
#elif defined(ENTRY_MAPPING_KEXEC_SETUP)
/*
diff --git a/arch/powerpc/kernel/head_fsl_booke.S
b/arch/powerpc/kernel/head_fsl_booke.S
index dab091e..134064d 100644
--- a/arch/powerpc/kernel/head_fsl_booke.S
+++ b/arch/powerpc/kernel/head_fsl_booke.S
@@ -73,6 +73,33 @@ _ENTRY(_start);
li r24,0 /* CPU number */
li r23,0 /* phys kernel start (high) */
+#ifdef CONFIG_RELOCATABLE
+ bl 0f /* Get our runtime address */
+0: mflr r3 /* Make it accessible */
+ addis r3,r3,(_stext - 0b)@ha
+ addi r3,r3,(_stext - 0b)@l /* Get our current runtime base */
+
+ /* Translate _stext address to physical, save in r23/r25 */
+ bl get_phys_addr
+ mr r23,r3
+ mr r25,r4
+
+ /*
+ * We have the runtime (virutal) address of our base.
+ * We calculate our shift of offset from a 256M page.
+ * We could map the 256M page we belong to at PAGE_OFFSET and
+ * get going from there.
+ */
+ lis r4,KERNELBASE@h
+ ori r4,r4,KERNELBASE@l
+ rlwinm r6,r25,0,0xfffffff /* r6 = PHYS_START % 256M */
+ rlwinm r5,r4,0,0xfffffff /* r5 = KERNELBASE % 256M */
+ subf r3,r5,r6 /* r3 = r6 - r5 */
+ add r3,r4,r3 /* Required Virutal Address */
+
+ bl relocate
+#endif
+
/* 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
@@ -182,6 +209,16 @@ _ENTRY(__early_start)
bl early_init
+#ifdef CONFIG_RELOCATABLE
+#ifdef CONFIG_PHYS_64BIT
+ mr r3,r23
+ mr r4,r25
+#else
+ mr r3,r25
+#endif
+ bl relocate_init
+#endif
+
#ifdef CONFIG_DYNAMIC_MEMSTART
lis r3,kernstart_addr@ha
la r3,kernstart_addr@l(r3)
diff --git a/arch/powerpc/mm/fsl_booke_mmu.c b/arch/powerpc/mm/fsl_booke_mmu.c
index 07ba45b..5fe271c 100644
--- a/arch/powerpc/mm/fsl_booke_mmu.c
+++ b/arch/powerpc/mm/fsl_booke_mmu.c
@@ -241,4 +241,32 @@ void setup_initial_memory_limit(phys_addr_t
first_memblock_base,
/* 64M mapped initially according to head_fsl_booke.S */
memblock_set_current_limit(min_t(u64, limit, 0x04000000));
}
+
+#ifdef CONFIG_RELOCATABLE
+notrace void __init relocate_init(phys_addr_t start)
+{
+ unsigned long base = KERNELBASE;
+
+ /*
+ * Relocatable kernel support based on processing of dynamic
+ * relocation entries.
+ * Compute the virt_phys_offset :
+ * virt_phys_offset = stext.run - kernstart_addr
+ *
+ * stext.run = (KERNELBASE & ~0xfffffff) + (kernstart_addr & 0xfffffff)
+ * When we relocate, we have :
+ *
+ * (kernstart_addr & 0xfffffff) = (stext.run & 0xfffffff)
+ *
+ * hence:
+ * virt_phys_offset = (KERNELBASE & ~0xfffffff) -
+ * (kernstart_addr & ~0xfffffff)
+ *
+ */
+ kernstart_addr = start;
+ start &= ~0xfffffff;
+ base &= ~0xfffffff;
+ virt_phys_offset = base - start;
+}
+#endif
#endif
--
1.8.1.4
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