From: Scott Wood Date: Fri, 8 Aug 2014 23:44:01 +0000 (-0500) Subject: powerpc/nohash: Split __early_init_mmu() into boot and secondary X-Git-Url: http://git.cdn.openwrt.org/?a=commitdiff_plain;h=5d61a2172a0142c635ab6d7c3b1589af85a3603e;p=openwrt%2Fstaging%2Fblogic.git powerpc/nohash: Split __early_init_mmu() into boot and secondary __early_init_mmu() does some things that are really only needed by the boot cpu. On FSL booke, This includes calling memblock_enforce_memory_limit(), which is labelled __init. Secondary cpu init code can't be __init as that would break CPU hotplug. While it's probably a bug that memblock_enforce_memory_limit() isn't __init_memblock instead, there's no reason why we should be doing this stuff for secondary cpus in the first place. Signed-off-by: Scott Wood Signed-off-by: Benjamin Herrenschmidt --- diff --git a/arch/powerpc/mm/tlb_nohash.c b/arch/powerpc/mm/tlb_nohash.c index 92cb18d52ea8..f38ea4df6a85 100644 --- a/arch/powerpc/mm/tlb_nohash.c +++ b/arch/powerpc/mm/tlb_nohash.c @@ -581,42 +581,10 @@ static void setup_mmu_htw(void) /* * Early initialization of the MMU TLB code */ -static void __early_init_mmu(int boot_cpu) +static void early_init_this_mmu(void) { unsigned int mas4; - /* XXX This will have to be decided at runtime, but right - * now our boot and TLB miss code hard wires it. Ideally - * we should find out a suitable page size and patch the - * TLB miss code (either that or use the PACA to store - * the value we want) - */ - mmu_linear_psize = MMU_PAGE_1G; - - /* XXX This should be decided at runtime based on supported - * page sizes in the TLB, but for now let's assume 16M is - * always there and a good fit (which it probably is) - * - * Freescale booke only supports 4K pages in TLB0, so use that. - */ - if (mmu_has_feature(MMU_FTR_TYPE_FSL_E)) - mmu_vmemmap_psize = MMU_PAGE_4K; - else - mmu_vmemmap_psize = MMU_PAGE_16M; - - /* XXX This code only checks for TLB 0 capabilities and doesn't - * check what page size combos are supported by the HW. It - * also doesn't handle the case where a separate array holds - * the IND entries from the array loaded by the PT. - */ - if (boot_cpu) { - /* Look for supported page sizes */ - setup_page_sizes(); - - /* Look for HW tablewalk support */ - setup_mmu_htw(); - } - /* Set MAS4 based on page table setting */ mas4 = 0x4 << MAS4_WIMGED_SHIFT; @@ -650,11 +618,6 @@ static void __early_init_mmu(int boot_cpu) } mtspr(SPRN_MAS4, mas4); - /* Set the global containing the top of the linear mapping - * for use by the TLB miss code - */ - linear_map_top = memblock_end_of_DRAM(); - #ifdef CONFIG_PPC_FSL_BOOK3E if (mmu_has_feature(MMU_FTR_TYPE_FSL_E)) { unsigned int num_cams; @@ -662,10 +625,49 @@ static void __early_init_mmu(int boot_cpu) /* use a quarter of the TLBCAM for bolted linear map */ num_cams = (mfspr(SPRN_TLB1CFG) & TLBnCFG_N_ENTRY) / 4; linear_map_top = map_mem_in_cams(linear_map_top, num_cams); + } +#endif - /* limit memory so we dont have linear faults */ - memblock_enforce_memory_limit(linear_map_top); + /* A sync won't hurt us after mucking around with + * the MMU configuration + */ + mb(); +} +static void __init early_init_mmu_global(void) +{ + /* XXX This will have to be decided at runtime, but right + * now our boot and TLB miss code hard wires it. Ideally + * we should find out a suitable page size and patch the + * TLB miss code (either that or use the PACA to store + * the value we want) + */ + mmu_linear_psize = MMU_PAGE_1G; + + /* XXX This should be decided at runtime based on supported + * page sizes in the TLB, but for now let's assume 16M is + * always there and a good fit (which it probably is) + * + * Freescale booke only supports 4K pages in TLB0, so use that. + */ + if (mmu_has_feature(MMU_FTR_TYPE_FSL_E)) + mmu_vmemmap_psize = MMU_PAGE_4K; + else + mmu_vmemmap_psize = MMU_PAGE_16M; + + /* XXX This code only checks for TLB 0 capabilities and doesn't + * check what page size combos are supported by the HW. It + * also doesn't handle the case where a separate array holds + * the IND entries from the array loaded by the PT. + */ + /* Look for supported page sizes */ + setup_page_sizes(); + + /* Look for HW tablewalk support */ + setup_mmu_htw(); + +#ifdef CONFIG_PPC_FSL_BOOK3E + if (mmu_has_feature(MMU_FTR_TYPE_FSL_E)) { if (book3e_htw_mode == PPC_HTW_NONE) { extlb_level_exc = EX_TLB_SIZE; patch_exception(0x1c0, exc_data_tlb_miss_bolted_book3e); @@ -675,22 +677,41 @@ static void __early_init_mmu(int boot_cpu) } #endif - /* A sync won't hurt us after mucking around with - * the MMU configuration + /* Set the global containing the top of the linear mapping + * for use by the TLB miss code */ - mb(); + linear_map_top = memblock_end_of_DRAM(); +} + +static void __init early_mmu_set_memory_limit(void) +{ +#ifdef CONFIG_PPC_FSL_BOOK3E + if (mmu_has_feature(MMU_FTR_TYPE_FSL_E)) { + /* + * Limit memory so we dont have linear faults. + * Unlike memblock_set_current_limit, which limits + * memory available during early boot, this permanently + * reduces the memory available to Linux. We need to + * do this because highmem is not supported on 64-bit. + */ + memblock_enforce_memory_limit(linear_map_top); + } +#endif memblock_set_current_limit(linear_map_top); } +/* boot cpu only */ void __init early_init_mmu(void) { - __early_init_mmu(1); + early_init_mmu_global(); + early_init_this_mmu(); + early_mmu_set_memory_limit(); } void early_init_mmu_secondary(void) { - __early_init_mmu(0); + early_init_this_mmu(); } void setup_initial_memory_limit(phys_addr_t first_memblock_base,