From eba5de8dc163fac4d20f0afed8183431491b570f Mon Sep 17 00:00:00 2001 From: Scott Wood Date: Tue, 6 Oct 2015 22:48:10 -0500 Subject: [PATCH] powerpc/fsl-booke-64: Don't limit ppc64_rma_size to one TLB entry This is required for kdump to work when loaded at at an address that does not fall within the first TLB entry -- which can easily happen because while the lower limit is enforced via reserved memory, which doesn't affect how much is mapped, the upper limit is enforced via a different mechanism that does. Thus, more TLB entries are needed than would normally be used, as the total memory to be mapped might not be a power of two. Signed-off-by: Scott Wood --- arch/powerpc/mm/fsl_booke_mmu.c | 22 +++++++++++++++------- arch/powerpc/mm/mmu_decl.h | 3 ++- arch/powerpc/mm/tlb_nohash.c | 24 +++++++++++++++++------- 3 files changed, 34 insertions(+), 15 deletions(-) diff --git a/arch/powerpc/mm/fsl_booke_mmu.c b/arch/powerpc/mm/fsl_booke_mmu.c index bb1f88c10377..f3afe3d97f6b 100644 --- a/arch/powerpc/mm/fsl_booke_mmu.c +++ b/arch/powerpc/mm/fsl_booke_mmu.c @@ -169,7 +169,8 @@ unsigned long calc_cam_sz(unsigned long ram, unsigned long virt, } static unsigned long map_mem_in_cams_addr(phys_addr_t phys, unsigned long virt, - unsigned long ram, int max_cam_idx) + unsigned long ram, int max_cam_idx, + bool dryrun) { int i; unsigned long amount_mapped = 0; @@ -179,7 +180,9 @@ static unsigned long map_mem_in_cams_addr(phys_addr_t phys, unsigned long virt, unsigned long cam_sz; cam_sz = calc_cam_sz(ram, virt, phys); - settlbcam(i, virt, phys, cam_sz, pgprot_val(PAGE_KERNEL_X), 0); + if (!dryrun) + settlbcam(i, virt, phys, cam_sz, + pgprot_val(PAGE_KERNEL_X), 0); ram -= cam_sz; amount_mapped += cam_sz; @@ -187,6 +190,9 @@ static unsigned long map_mem_in_cams_addr(phys_addr_t phys, unsigned long virt, phys += cam_sz; } + if (dryrun) + return amount_mapped; + loadcam_multi(0, i, max_cam_idx); tlbcam_index = i; @@ -199,12 +205,12 @@ static unsigned long map_mem_in_cams_addr(phys_addr_t phys, unsigned long virt, return amount_mapped; } -unsigned long map_mem_in_cams(unsigned long ram, int max_cam_idx) +unsigned long map_mem_in_cams(unsigned long ram, int max_cam_idx, bool dryrun) { unsigned long virt = PAGE_OFFSET; phys_addr_t phys = memstart_addr; - return map_mem_in_cams_addr(phys, virt, ram, max_cam_idx); + return map_mem_in_cams_addr(phys, virt, ram, max_cam_idx, dryrun); } #ifdef CONFIG_PPC32 @@ -235,7 +241,7 @@ void __init adjust_total_lowmem(void) ram = min((phys_addr_t)__max_low_memory, (phys_addr_t)total_lowmem); i = switch_to_as1(); - __max_low_memory = map_mem_in_cams(ram, CONFIG_LOWMEM_CAM_NUM); + __max_low_memory = map_mem_in_cams(ram, CONFIG_LOWMEM_CAM_NUM, false); restore_to_as0(i, 0, 0, 1); pr_info("Memory CAM mapping: "); @@ -303,10 +309,12 @@ notrace void __init relocate_init(u64 dt_ptr, phys_addr_t start) 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); + map_mem_in_cams(0x4000000, CONFIG_LOWMEM_CAM_NUM, + false); else map_mem_in_cams_addr(start, PAGE_OFFSET + offset, - 0x4000000, CONFIG_LOWMEM_CAM_NUM); + 0x4000000, CONFIG_LOWMEM_CAM_NUM, + false); restore_to_as0(n, offset, __va(dt_ptr), 1); /* We should never reach here */ panic("Relocation error"); diff --git a/arch/powerpc/mm/mmu_decl.h b/arch/powerpc/mm/mmu_decl.h index 27c3a2d3a4f1..9f58ff44a075 100644 --- a/arch/powerpc/mm/mmu_decl.h +++ b/arch/powerpc/mm/mmu_decl.h @@ -141,7 +141,8 @@ extern void MMU_init_hw(void); extern unsigned long mmu_mapin_ram(unsigned long top); #elif defined(CONFIG_PPC_FSL_BOOK3E) -extern unsigned long map_mem_in_cams(unsigned long ram, int max_cam_idx); +extern unsigned long map_mem_in_cams(unsigned long ram, int max_cam_idx, + bool dryrun); extern unsigned long calc_cam_sz(unsigned long ram, unsigned long virt, phys_addr_t phys); #ifdef CONFIG_PPC32 diff --git a/arch/powerpc/mm/tlb_nohash.c b/arch/powerpc/mm/tlb_nohash.c index a7381fbdd6ab..bb04e4df3100 100644 --- a/arch/powerpc/mm/tlb_nohash.c +++ b/arch/powerpc/mm/tlb_nohash.c @@ -648,7 +648,7 @@ static void early_init_this_mmu(void) if (map) linear_map_top = map_mem_in_cams(linear_map_top, - num_cams); + num_cams, false); } #endif @@ -746,10 +746,14 @@ void setup_initial_memory_limit(phys_addr_t first_memblock_base, * entries are supported though that may eventually * change. * - * on FSL Embedded 64-bit, we adjust the RMA size to match the - * first bolted TLB entry size. We still limit max to 1G even if - * the TLB could cover more. This is due to what the early init - * code is setup to do. + * on FSL Embedded 64-bit, usually all RAM is bolted, but with + * unusual memory sizes it's possible for some RAM to not be mapped + * (such RAM is not used at all by Linux, since we don't support + * highmem on 64-bit). We limit ppc64_rma_size to what would be + * mappable if this memblock is the only one. Additional memblocks + * can only increase, not decrease, the amount that ends up getting + * mapped. We still limit max to 1G even if we'll eventually map + * more. This is due to what the early init code is set up to do. * * We crop it to the size of the first MEMBLOCK to * avoid going over total available memory just in case... @@ -757,8 +761,14 @@ void setup_initial_memory_limit(phys_addr_t first_memblock_base, #ifdef CONFIG_PPC_FSL_BOOK3E if (mmu_has_feature(MMU_FTR_TYPE_FSL_E)) { unsigned long linear_sz; - linear_sz = calc_cam_sz(first_memblock_size, PAGE_OFFSET, - first_memblock_base); + unsigned int num_cams; + + /* use a quarter of the TLBCAM for bolted linear map */ + num_cams = (mfspr(SPRN_TLB1CFG) & TLBnCFG_N_ENTRY) / 4; + + linear_sz = map_mem_in_cams(first_memblock_size, num_cams, + true); + ppc64_rma_size = min_t(u64, linear_sz, 0x40000000); } else #endif