diff options
Diffstat (limited to 'arch/powerpc')
| -rw-r--r-- | arch/powerpc/kernel/head_fsl_booke.S | 74 | ||||
| -rw-r--r-- | arch/powerpc/mm/fsl_booke_mmu.c | 42 | ||||
| -rw-r--r-- | arch/powerpc/mm/mmu_decl.h | 2 |
3 files changed, 106 insertions, 12 deletions
diff --git a/arch/powerpc/kernel/head_fsl_booke.S b/arch/powerpc/kernel/head_fsl_booke.S index 75f0223e6d0d..b1f7edc3c360 100644 --- a/arch/powerpc/kernel/head_fsl_booke.S +++ b/arch/powerpc/kernel/head_fsl_booke.S @@ -81,6 +81,39 @@ _ENTRY(_start); mr r23,r3 mr r25,r4 + bl 0f +0: mflr r8 + addis r3,r8,(is_second_reloc - 0b)@ha + lwz r19,(is_second_reloc - 0b)@l(r3) + + /* Check if this is the second relocation. */ + cmpwi r19,1 + bne 1f + + /* + * For the second relocation, we already get the real memstart_addr + * from device tree. So we will map PAGE_OFFSET to memstart_addr, + * then the virtual address of start kernel should be: + * PAGE_OFFSET + (kernstart_addr - memstart_addr) + * Since the offset between kernstart_addr and memstart_addr should + * never be beyond 1G, so we can just use the lower 32bit of them + * for the calculation. + */ + lis r3,PAGE_OFFSET@h + + addis r4,r8,(kernstart_addr - 0b)@ha + addi r4,r4,(kernstart_addr - 0b)@l + lwz r5,4(r4) + + addis r6,r8,(memstart_addr - 0b)@ha + addi r6,r6,(memstart_addr - 0b)@l + lwz r7,4(r6) + + subf r5,r7,r5 + add r3,r3,r5 + b 2f + +1: /* * We have the runtime (virutal) address of our base. * We calculate our shift of offset from a 64M page. @@ -94,7 +127,14 @@ _ENTRY(_start); subf r3,r5,r6 /* r3 = r6 - r5 */ add r3,r4,r3 /* Required Virtual Address */ - bl relocate +2: bl relocate + + /* + * For the second relocation, we already set the right tlb entries + * for the kernel space, so skip the code in fsl_booke_entry_mapping.S + */ + cmpwi r19,1 + beq set_ivor #endif /* We try to not make any assumptions about how the boot loader @@ -122,6 +162,7 @@ _ENTRY(__early_start) #include "fsl_booke_entry_mapping.S" #undef ENTRY_MAPPING_BOOT_SETUP +set_ivor: /* Establish the interrupt vector offsets */ SET_IVOR(0, CriticalInput); SET_IVOR(1, MachineCheck); @@ -207,11 +248,13 @@ _ENTRY(__early_start) bl early_init #ifdef CONFIG_RELOCATABLE + mr r3,r30 + mr r4,r31 #ifdef CONFIG_PHYS_64BIT - mr r3,r23 - mr r4,r25 + mr r5,r23 + mr r6,r25 #else - mr r3,r25 + mr r5,r25 #endif bl relocate_init #endif @@ -1207,6 +1250,9 @@ _GLOBAL(switch_to_as1) /* * Restore to the address space 0 and also invalidate the tlb entry created * by switch_to_as1. + * r3 - the tlb entry which should be invalidated + * r4 - __pa(PAGE_OFFSET in AS1) - __pa(PAGE_OFFSET in AS0) + * r5 - device tree virtual address. If r4 is 0, r5 is ignored. */ _GLOBAL(restore_to_as0) mflr r0 @@ -1215,7 +1261,15 @@ _GLOBAL(restore_to_as0) 0: mflr r9 addi r9,r9,1f - 0b - mfmsr r7 + /* + * We may map the PAGE_OFFSET in AS0 to a different physical address, + * so we need calculate the right jump and device tree address based + * on the offset passed by r4. + */ + add r9,r9,r4 + add r5,r5,r4 + +2: mfmsr r7 li r8,(MSR_IS | MSR_DS) andc r7,r7,r8 @@ -1234,9 +1288,19 @@ _GLOBAL(restore_to_as0) mtspr SPRN_MAS1,r9 tlbwe isync + + cmpwi r4,0 + bne 3f mtlr r0 blr + /* + * The PAGE_OFFSET will map to a different physical address, + * jump to _start to do another relocation again. + */ +3: mr r3,r5 + bl _start + /* * We put a few things here that have to be page-aligned. This stuff * goes at the beginning of the data segment, which is page-aligned. diff --git a/arch/powerpc/mm/fsl_booke_mmu.c b/arch/powerpc/mm/fsl_booke_mmu.c index ca956c83e3a2..95deb9fdf92f 100644 --- a/arch/powerpc/mm/fsl_booke_mmu.c +++ b/arch/powerpc/mm/fsl_booke_mmu.c @@ -231,7 +231,7 @@ void __init adjust_total_lowmem(void) i = switch_to_as1(); __max_low_memory = map_mem_in_cams(ram, CONFIG_LOWMEM_CAM_NUM); - restore_to_as0(i); + restore_to_as0(i, 0, 0); pr_info("Memory CAM mapping: "); for (i = 0; i < tlbcam_index - 1; i++) @@ -252,17 +252,25 @@ void setup_initial_memory_limit(phys_addr_t first_memblock_base, } #ifdef CONFIG_RELOCATABLE -notrace void __init relocate_init(phys_addr_t start) +int __initdata is_second_reloc; +notrace void __init relocate_init(u64 dt_ptr, phys_addr_t start) { unsigned long base = KERNELBASE; + kernstart_addr = start; + if (is_second_reloc) { + virt_phys_offset = PAGE_OFFSET - memstart_addr; + return; + } + /* * Relocatable kernel support based on processing of dynamic - * relocation entries. - * Compute the virt_phys_offset : + * relocation entries. Before we get the real memstart_addr, + * We will compute the virt_phys_offset like this: * virt_phys_offset = stext.run - kernstart_addr * - * stext.run = (KERNELBASE & ~0x3ffffff) + (kernstart_addr & 0x3ffffff) + * stext.run = (KERNELBASE & ~0x3ffffff) + + * (kernstart_addr & 0x3ffffff) * When we relocate, we have : * * (kernstart_addr & 0x3ffffff) = (stext.run & 0x3ffffff) @@ -272,10 +280,32 @@ notrace void __init relocate_init(phys_addr_t start) * (kernstart_addr & ~0x3ffffff) * */ - kernstart_addr = start; start &= ~0x3ffffff; base &= ~0x3ffffff; virt_phys_offset = base - start; + early_get_first_memblock_info(__va(dt_ptr), NULL); + /* + * We now get the memstart_addr, then we should check if this + * address is the same as what the PAGE_OFFSET map to now. If + * not we have to change the map of PAGE_OFFSET to memstart_addr + * and do a second relocation. + */ + if (start != memstart_addr) { + int n; + long offset = start - memstart_addr; + + is_second_reloc = 1; + n = switch_to_as1(); + /* map a 64M area for the second relocation */ + if (memstart_addr > start) + map_mem_in_cams(0x4000000, CONFIG_LOWMEM_CAM_NUM); + else + map_mem_in_cams_addr(start, PAGE_OFFSET + offset, + 0x4000000, CONFIG_LOWMEM_CAM_NUM); + restore_to_as0(n, offset, __va(dt_ptr)); + /* We should never reach here */ + panic("Relocation error"); + } } #endif #endif diff --git a/arch/powerpc/mm/mmu_decl.h b/arch/powerpc/mm/mmu_decl.h index eefbf7bb4331..91da910210cb 100644 --- a/arch/powerpc/mm/mmu_decl.h +++ b/arch/powerpc/mm/mmu_decl.h @@ -149,7 +149,7 @@ extern void MMU_init_hw(void); extern unsigned long mmu_mapin_ram(unsigned long top); extern void adjust_total_lowmem(void); extern int switch_to_as1(void); -extern void restore_to_as0(int esel); +extern void restore_to_as0(int esel, int offset, void *dt_ptr); #endif extern void loadcam_entry(unsigned int index); |