From 5af543be14cdad5d515631c5fe6984813fe0db70 Mon Sep 17 00:00:00 2001 From: Christophe Leroy Date: Thu, 29 Nov 2018 14:07:13 +0000 Subject: [PATCH] powerpc/8xx: Temporarily disable 16k pages and hugepages In preparation of making use of hardware assistance in TLB handlers, this patch temporarily disables 16K pages and hugepages. The reason is that when using HW assistance in 4K pages mode, the linux model fit with the HW model for 4K pages and 8M pages. However for 16K pages and 512K mode some additional work is needed to get linux model fit with HW model. For the 8M pages, they will naturaly come back when we switch to HW assistance, without any additional handling. In order to keep the following patch smaller, the removal of the current special handling for 8M pages gets removed here as well. Therefore the 4K pages mode will be implemented first and without support for 512k hugepages. Then the 512k hugepages will be brought back. And the 16K pages will be implemented in the following step. Signed-off-by: Christophe Leroy Signed-off-by: Michael Ellerman --- arch/powerpc/Kconfig | 2 +- arch/powerpc/kernel/head_8xx.S | 74 +++------------------------------- arch/powerpc/mm/tlb_nohash.c | 6 --- 3 files changed, 6 insertions(+), 76 deletions(-) diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig index 8ea7c2c02cbf..bfb5ee99396c 100644 --- a/arch/powerpc/Kconfig +++ b/arch/powerpc/Kconfig @@ -689,7 +689,7 @@ config PPC_4K_PAGES config PPC_16K_PAGES bool "16k page size" - depends on 44x || PPC_8xx + depends on 44x config PPC_64K_PAGES bool "64k page size" diff --git a/arch/powerpc/kernel/head_8xx.S b/arch/powerpc/kernel/head_8xx.S index c203defe49a4..01f58b1d9ae7 100644 --- a/arch/powerpc/kernel/head_8xx.S +++ b/arch/powerpc/kernel/head_8xx.S @@ -314,7 +314,7 @@ SystemCall: InstructionTLBMiss: mtspr SPRN_SPRG_SCRATCH0, r10 mtspr SPRN_SPRG_SCRATCH1, r11 -#if defined(ITLB_MISS_KERNEL) || defined(CONFIG_HUGETLB_PAGE) +#ifdef ITLB_MISS_KERNEL mtspr SPRN_SPRG_SCRATCH2, r12 #endif @@ -325,10 +325,8 @@ InstructionTLBMiss: INVALIDATE_ADJACENT_PAGES_CPU15(r11, r10) /* Only modules will cause ITLB Misses as we always * pin the first 8MB of kernel memory */ -#if defined(ITLB_MISS_KERNEL) || defined(CONFIG_HUGETLB_PAGE) - mfcr r12 -#endif #ifdef ITLB_MISS_KERNEL + mfcr r12 #if defined(SIMPLE_KERNEL_ADDRESS) && defined(CONFIG_PIN_TLB_TEXT) andis. r11, r10, 0x8000 /* Address >= 0x80000000 */ #else @@ -360,15 +358,9 @@ InstructionTLBMiss: /* Extract level 2 index */ rlwinm r10, r10, 32 - (PAGE_SHIFT - 2), 32 - PAGE_SHIFT, 29 -#ifdef CONFIG_HUGETLB_PAGE - mtcr r11 - bt- 28, 10f /* bit 28 = Large page (8M) */ - bt- 29, 20f /* bit 29 = Large page (8M or 512k) */ -#endif rlwimi r10, r11, 0, 0, 32 - PAGE_SHIFT - 1 /* Add level 2 base */ lwz r10, 0(r10) /* Get the pte */ -4: -#if defined(ITLB_MISS_KERNEL) || defined(CONFIG_HUGETLB_PAGE) +#ifdef ITLB_MISS_KERNEL mtcr r12 #endif /* Load the MI_TWC with the attributes for this "segment." */ @@ -393,7 +385,7 @@ InstructionTLBMiss: /* Restore registers */ 0: mfspr r10, SPRN_SPRG_SCRATCH0 mfspr r11, SPRN_SPRG_SCRATCH1 -#if defined(ITLB_MISS_KERNEL) || defined(CONFIG_HUGETLB_PAGE) +#ifdef ITLB_MISS_KERNEL mfspr r12, SPRN_SPRG_SCRATCH2 #endif rfi @@ -406,35 +398,12 @@ InstructionTLBMiss: stw r10, (itlb_miss_counter - PAGE_OFFSET)@l(0) mfspr r10, SPRN_SPRG_SCRATCH0 mfspr r11, SPRN_SPRG_SCRATCH1 -#if defined(ITLB_MISS_KERNEL) || defined(CONFIG_HUGETLB_PAGE) +#ifdef ITLB_MISS_KERNEL mfspr r12, SPRN_SPRG_SCRATCH2 #endif rfi #endif -#ifdef CONFIG_HUGETLB_PAGE -10: /* 8M pages */ -#ifdef CONFIG_PPC_16K_PAGES - /* Extract level 2 index */ - rlwinm r10, r10, 32 - (PAGE_SHIFT_8M - PAGE_SHIFT), 32 + PAGE_SHIFT_8M - (PAGE_SHIFT << 1), 29 - /* Add level 2 base */ - rlwimi r10, r11, 0, 0, 32 + PAGE_SHIFT_8M - (PAGE_SHIFT << 1) - 1 -#else - /* Level 2 base */ - rlwinm r10, r11, 0, ~HUGEPD_SHIFT_MASK -#endif - lwz r10, 0(r10) /* Get the pte */ - b 4b - -20: /* 512k pages */ - /* Extract level 2 index */ - rlwinm r10, r10, 32 - (PAGE_SHIFT_512K - PAGE_SHIFT), 32 + PAGE_SHIFT_512K - (PAGE_SHIFT << 1), 29 - /* Add level 2 base */ - rlwimi r10, r11, 0, 0, 32 + PAGE_SHIFT_512K - (PAGE_SHIFT << 1) - 1 - lwz r10, 0(r10) /* Get the pte */ - b 4b -#endif - . = 0x1200 DataStoreTLBMiss: mtspr SPRN_SPRG_SCRATCH0, r10 @@ -472,11 +441,6 @@ DataStoreTLBMiss: */ /* Extract level 2 index */ rlwinm r10, r10, 32 - (PAGE_SHIFT - 2), 32 - PAGE_SHIFT, 29 -#ifdef CONFIG_HUGETLB_PAGE - mtcr r11 - bt- 28, 10f /* bit 28 = Large page (8M) */ - bt- 29, 20f /* bit 29 = Large page (8M or 512k) */ -#endif rlwimi r10, r11, 0, 0, 32 - PAGE_SHIFT - 1 /* Add level 2 base */ lwz r10, 0(r10) /* Get the pte */ 4: @@ -534,29 +498,6 @@ DataStoreTLBMiss: rfi #endif -#ifdef CONFIG_HUGETLB_PAGE -10: /* 8M pages */ - /* Extract level 2 index */ -#ifdef CONFIG_PPC_16K_PAGES - rlwinm r10, r10, 32 - (PAGE_SHIFT_8M - PAGE_SHIFT), 32 + PAGE_SHIFT_8M - (PAGE_SHIFT << 1), 29 - /* Add level 2 base */ - rlwimi r10, r11, 0, 0, 32 + PAGE_SHIFT_8M - (PAGE_SHIFT << 1) - 1 -#else - /* Level 2 base */ - rlwinm r10, r11, 0, ~HUGEPD_SHIFT_MASK -#endif - lwz r10, 0(r10) /* Get the pte */ - b 4b - -20: /* 512k pages */ - /* Extract level 2 index */ - rlwinm r10, r10, 32 - (PAGE_SHIFT_512K - PAGE_SHIFT), 32 + PAGE_SHIFT_512K - (PAGE_SHIFT << 1), 29 - /* Add level 2 base */ - rlwimi r10, r11, 0, 0, 32 + PAGE_SHIFT_512K - (PAGE_SHIFT << 1) - 1 - lwz r10, 0(r10) /* Get the pte */ - b 4b -#endif - /* This is an instruction TLB error on the MPC8xx. This could be due * to many reasons, such as executing guarded memory or illegal instruction * addresses. There is nothing to do but handle a big time error fault. @@ -773,12 +714,7 @@ FixupDAR:/* Entry point for dcbx workaround. */ /* concat physical page address(r11) and page offset(r10) */ 200: -#ifdef CONFIG_PPC_16K_PAGES - rlwinm r11, r11, 0, 0, 32 + PAGE_SHIFT_8M - (PAGE_SHIFT << 1) - 1 - rlwimi r11, r10, 32 - (PAGE_SHIFT_8M - 2), 32 + PAGE_SHIFT_8M - (PAGE_SHIFT << 1), 29 -#else rlwinm r11, r10, 0, ~HUGEPD_SHIFT_MASK -#endif lwz r11, 0(r11) /* Get the pte */ /* concat physical page address(r11) and page offset(r10) */ rlwimi r11, r10, 0, 32 - PAGE_SHIFT_8M, 31 diff --git a/arch/powerpc/mm/tlb_nohash.c b/arch/powerpc/mm/tlb_nohash.c index ae5d568e267f..4f79639e432f 100644 --- a/arch/powerpc/mm/tlb_nohash.c +++ b/arch/powerpc/mm/tlb_nohash.c @@ -97,12 +97,6 @@ struct mmu_psize_def mmu_psize_defs[MMU_PAGE_COUNT] = { .shift = 14, }, #endif - [MMU_PAGE_512K] = { - .shift = 19, - }, - [MMU_PAGE_8M] = { - .shift = 23, - }, }; #else struct mmu_psize_def mmu_psize_defs[MMU_PAGE_COUNT] = { -- 2.30.2