From: LEROY Christophe Date: Fri, 19 Sep 2014 08:36:08 +0000 (+0200) Subject: powerpc/8xx: Don't use MD_TWC for walk X-Git-Tag: firefly_0821_release~176^2~2621^2~23^2~25 X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=33fb845a6f019001b8ca3f532eb1a4de34547f42;p=firefly-linux-kernel-4.4.55.git powerpc/8xx: Don't use MD_TWC for walk MD_TWC can only be used properly with 4k pages. So lets calculate level 2 table index by ourselves. Signed-off-by: Christophe Leroy Signed-off-by: Scott Wood --- diff --git a/arch/powerpc/kernel/head_8xx.S b/arch/powerpc/kernel/head_8xx.S index c78f7fd342cb..3eea29ad1fcf 100644 --- a/arch/powerpc/kernel/head_8xx.S +++ b/arch/powerpc/kernel/head_8xx.S @@ -299,8 +299,6 @@ InstructionTLBMiss: addi r11, r10, -0x1000 tlbie r11 #endif - DO_8xx_CPU6(0x3780, r3) - mtspr SPRN_MD_EPN, r10 /* Have to use MD_EPN for walk, MI_EPN can't */ /* If we are faulting a kernel address, we have to use the * kernel page tables. @@ -328,10 +326,9 @@ InstructionTLBMiss: ori r11,r11,1 /* Set valid bit */ DO_8xx_CPU6(0x2b80, r3) mtspr SPRN_MI_TWC, r11 /* Set segment attributes */ - DO_8xx_CPU6(0x3b80, r3) - mtspr SPRN_MD_TWC, r11 /* Load pte table base address */ - mfspr r11, SPRN_MD_TWC /* ....and get the pte address */ - lwz r10, 0(r11) /* Get the pte */ + mfspr r11, SPRN_SRR0 /* Get effective address of fault */ + rlwinm r11, r11, 22, 20, 29 /* Extract level 2 index */ + lwzx r10, r10, r11 /* Get the pte */ #ifdef CONFIG_SWAP andi. r11, r10, _PAGE_ACCESSED | _PAGE_PRESENT @@ -397,12 +394,13 @@ DataStoreTLBMiss: /* We have a pte table, so load fetch the pte from the table. */ - ori r11, r11, 1 /* Set valid bit in physical L2 page */ - DO_8xx_CPU6(0x3b80, r3) - mtspr SPRN_MD_TWC, r11 /* Load pte table base address */ - mfspr r10, SPRN_MD_TWC /* ....and get the pte address */ + mfspr r10, SPRN_MD_EPN /* Get address of fault */ + /* Extract level 2 index */ + rlwinm r10, r10, 22, 20, 29 + rlwimi r10, r11, 0, 0, 19 /* Add level 2 base */ lwz r10, 0(r10) /* Get the pte */ + ori r11, r11, 1 /* Set valid bit in physical L2 page */ /* Insert the Guarded flag into the TWC from the Linux PTE. * It is bit 27 of both the Linux PTE and the TWC (at least * I got that right :-). It will be better when we can put @@ -528,18 +526,16 @@ FixupDAR:/* Entry point for dcbx workaround. */ /* fetch instruction from memory. */ mfspr r10, SPRN_SRR0 andis. r11, r10, 0x8000 /* Address >= 0x80000000 */ - DO_8xx_CPU6(0x3780, r3) - mtspr SPRN_MD_EPN, r10 mfspr r11, SPRN_M_TW /* Get level 1 table base address */ beq- 3f /* Branch if user space */ lis r11, (swapper_pg_dir-PAGE_OFFSET)@h ori r11, r11, (swapper_pg_dir-PAGE_OFFSET)@l 3: rlwinm r10, r10, 12, 20, 29 /* Extract level 1 index */ lwzx r11, r10, r11 /* Get the level 1 entry */ - DO_8xx_CPU6(0x3b80, r3) - mtspr SPRN_MD_TWC, r11 /* Load pte table base address */ - mfspr r11, SPRN_MD_TWC /* ....and get the pte address */ - lwz r11, 0(r11) /* Get the pte */ + rlwinm r10, r11,0,0,19 /* Extract page descriptor page address */ + mfspr r11, SPRN_SRR0 /* Get effective address of fault */ + rlwinm r11, r11, 22, 20, 29 /* Extract level 2 index */ + lwzx r11, r10, r11 /* Get the pte */ #ifdef CONFIG_8xx_CPU6 lwz r3, 8(r0) /* restore r3 from memory */ #endif