diff options
Diffstat (limited to 'arch/powerpc/kernel/head_8xx.S')
| -rw-r--r-- | arch/powerpc/kernel/head_8xx.S | 70 |
1 files changed, 47 insertions, 23 deletions
diff --git a/arch/powerpc/kernel/head_8xx.S b/arch/powerpc/kernel/head_8xx.S index 3ef743fa5d7..1f1a04b5c2a 100644 --- a/arch/powerpc/kernel/head_8xx.S +++ b/arch/powerpc/kernel/head_8xx.S @@ -71,9 +71,6 @@ _ENTRY(_start); * in the first level table, but that would require many changes to the * Linux page directory/table functions that I don't want to do right now. * - * I used to use SPRG2 for a temporary register in the TLB handler, but it - * has since been put to other uses. I now use a hack to save a register - * and the CCR at memory location 0.....Someday I'll fix this..... * -- Dan */ .globl __start @@ -302,8 +299,13 @@ InstructionTLBMiss: DO_8xx_CPU6(0x3f80, r3) mtspr SPRN_M_TW, r10 /* Save a couple of working registers */ mfcr r10 +#ifdef CONFIG_8xx_CPU6 stw r10, 0(r0) stw r11, 4(r0) +#else + mtspr SPRN_DAR, r10 + mtspr SPRN_SPRG2, r11 +#endif mfspr r10, SPRN_SRR0 /* Get effective address of fault */ #ifdef CONFIG_8xx_CPU15 addi r11, r10, 0x1000 @@ -318,12 +320,16 @@ InstructionTLBMiss: /* If we are faulting a kernel address, we have to use the * kernel page tables. */ +#ifdef CONFIG_MODULES + /* Only modules will cause ITLB Misses as we always + * pin the first 8MB of kernel memory */ andi. r11, r10, 0x0800 /* Address >= 0x80000000 */ beq 3f lis r11, swapper_pg_dir@h ori r11, r11, swapper_pg_dir@l rlwimi r10, r11, 0, 2, 19 3: +#endif lwz r11, 0(r10) /* Get the level 1 entry */ rlwinm. r10, r11,0,0,19 /* Extract page descriptor page address */ beq 2f /* If zero, don't try to find a pte */ @@ -339,31 +345,35 @@ InstructionTLBMiss: mfspr r11, SPRN_MD_TWC /* ....and get the pte address */ lwz r10, 0(r11) /* Get the pte */ +#ifdef CONFIG_SWAP andi. r11, r10, _PAGE_ACCESSED | _PAGE_PRESENT cmpwi cr0, r11, _PAGE_ACCESSED | _PAGE_PRESENT bne- cr0, 2f - - /* Clear PP lsb, 0x400 */ - rlwinm r10, r10, 0, 22, 20 - +#endif /* The Linux PTE won't go exactly into the MMU TLB. - * Software indicator bits 22 and 28 must be clear. + * Software indicator bits 21 and 28 must be clear. * Software indicator bits 24, 25, 26, and 27 must be * set. All other Linux PTE bits control the behavior * of the MMU. */ li r11, 0x00f0 - rlwimi r10, r11, 0, 24, 28 /* Set 24-27, clear 28 */ + rlwimi r10, r11, 0, 0x07f8 /* Set 24-27, clear 21-23,28 */ DO_8xx_CPU6(0x2d80, r3) mtspr SPRN_MI_RPN, r10 /* Update TLB entry */ - mfspr r10, SPRN_M_TW /* Restore registers */ + /* Restore registers */ +#ifndef CONFIG_8xx_CPU6 + mfspr r10, SPRN_DAR + mtcr r10 + mtspr SPRN_DAR, r11 /* Tag DAR */ + mfspr r11, SPRN_SPRG2 +#else lwz r11, 0(r0) mtcr r11 lwz r11, 4(r0) -#ifdef CONFIG_8xx_CPU6 lwz r3, 8(r0) #endif + mfspr r10, SPRN_M_TW rfi 2: mfspr r11, SPRN_SRR1 @@ -373,13 +383,20 @@ InstructionTLBMiss: rlwinm r11, r11, 0, 0xffff mtspr SPRN_SRR1, r11 - mfspr r10, SPRN_M_TW /* Restore registers */ + /* Restore registers */ +#ifndef CONFIG_8xx_CPU6 + mfspr r10, SPRN_DAR + mtcr r10 + li r11, 0x00f0 + mtspr SPRN_DAR, r11 /* Tag DAR */ + mfspr r11, SPRN_SPRG2 +#else lwz r11, 0(r0) mtcr r11 lwz r11, 4(r0) -#ifdef CONFIG_8xx_CPU6 lwz r3, 8(r0) #endif + mfspr r10, SPRN_M_TW b InstructionAccess . = 0x1200 @@ -390,8 +407,13 @@ DataStoreTLBMiss: DO_8xx_CPU6(0x3f80, r3) mtspr SPRN_M_TW, r10 /* Save a couple of working registers */ mfcr r10 +#ifdef CONFIG_8xx_CPU6 stw r10, 0(r0) stw r11, 4(r0) +#else + mtspr SPRN_DAR, r10 + mtspr SPRN_SPRG2, r11 +#endif mfspr r10, SPRN_M_TWB /* Get level 1 table entry address */ /* If we are faulting a kernel address, we have to use the @@ -438,15 +460,14 @@ DataStoreTLBMiss: * r11 = ((r10 & PRESENT) & ((r10 & ACCESSED) >> 5)); * r10 = (r10 & ~PRESENT) | r11; */ +#ifdef CONFIG_SWAP rlwinm r11, r10, 32-5, _PAGE_PRESENT and r11, r11, r10 rlwimi r10, r11, 0, _PAGE_PRESENT - +#endif /* Honour kernel RO, User NA */ /* 0x200 == Extended encoding, bit 22 */ - /* r11 = (r10 & _PAGE_USER) >> 2 */ - rlwinm r11, r10, 32-2, 0x200 - or r10, r11, r10 + rlwimi r10, r10, 32-2, 0x200 /* Copy USER to bit 22, 0x200 */ /* r11 = (r10 & _PAGE_RW) >> 1 */ rlwinm r11, r10, 32-1, 0x200 or r10, r11, r10 @@ -460,18 +481,24 @@ DataStoreTLBMiss: * of the MMU. */ 2: li r11, 0x00f0 - mtspr SPRN_DAR,r11 /* Tag DAR */ rlwimi r10, r11, 0, 24, 28 /* Set 24-27, clear 28 */ DO_8xx_CPU6(0x3d80, r3) mtspr SPRN_MD_RPN, r10 /* Update TLB entry */ - mfspr r10, SPRN_M_TW /* Restore registers */ + /* Restore registers */ +#ifndef CONFIG_8xx_CPU6 + mfspr r10, SPRN_DAR + mtcr r10 + mtspr SPRN_DAR, r11 /* Tag DAR */ + mfspr r11, SPRN_SPRG2 +#else + mtspr SPRN_DAR, r11 /* Tag DAR */ lwz r11, 0(r0) mtcr r11 lwz r11, 4(r0) -#ifdef CONFIG_8xx_CPU6 lwz r3, 8(r0) #endif + mfspr r10, SPRN_M_TW rfi /* This is an instruction TLB error on the MPC8xx. This could be due @@ -683,9 +710,6 @@ start_here: tophys(r4,r2) addi r4,r4,THREAD /* init task's THREAD */ mtspr SPRN_SPRG_THREAD,r4 - li r3,0 - /* XXX What is that for ? SPRG2 appears otherwise unused on 8xx */ - mtspr SPRN_SPRG2,r3 /* 0 => r1 has kernel sp */ /* stack */ lis r1,init_thread_union@ha |