diff options
Diffstat (limited to 'arch/powerpc/kernel/head_8xx.S')
| -rw-r--r-- | arch/powerpc/kernel/head_8xx.S | 96 |
1 files changed, 0 insertions, 96 deletions
diff --git a/arch/powerpc/kernel/head_8xx.S b/arch/powerpc/kernel/head_8xx.S index c4ae85b8f8c..f2de8e8a825 100644 --- a/arch/powerpc/kernel/head_8xx.S +++ b/arch/powerpc/kernel/head_8xx.S @@ -500,102 +500,6 @@ DataTLBError: cmpwi cr0, r10, 0x00f0 beq- FixupDAR /* must be a buggy dcbX, icbi insn. */ DARFixed:/* Return from dcbx instruction bug workaround, r10 holds value of DAR */ - mfspr r11, SPRN_DSISR - /* As the DAR fixup may clear store we may have all 3 states zero. - * Make sure only 0x0200(store) falls down into DIRTY handling - */ - andis. r11, r11, 0x4a00 /* !translation, protection or store */ - srwi r11, r11, 16 - cmpwi cr0, r11, 0x0200 /* just store ? */ - bne 2f - /* Only Change bit left now, do it here as it is faster - * than trapping to the C fault handler. - */ - - /* The EA of a data TLB miss is automatically stored in the MD_EPN - * register. The EA of a data TLB error is automatically stored in - * the DAR, but not the MD_EPN register. We must copy the 20 most - * significant bits of the EA from the DAR to MD_EPN before we - * start walking the page tables. We also need to copy the CASID - * value from the M_CASID register. - * Addendum: The EA of a data TLB error is _supposed_ to be stored - * in DAR, but it seems that this doesn't happen in some cases, such - * as when the error is due to a dcbi instruction to a page with a - * TLB that doesn't have the changed bit set. In such cases, there - * does not appear to be any way to recover the EA of the error - * since it is neither in DAR nor MD_EPN. As a workaround, the - * _PAGE_HWWRITE bit is set for all kernel data pages when the PTEs - * are initialized in mapin_ram(). This will avoid the problem, - * assuming we only use the dcbi instruction on kernel addresses. - */ - - /* DAR is in r10 already */ - rlwinm r11, r10, 0, 0, 19 - ori r11, r11, MD_EVALID - mfspr r10, SPRN_M_CASID - rlwimi r11, r10, 0, 28, 31 - DO_8xx_CPU6(0x3780, r3) - mtspr SPRN_MD_EPN, r11 - - mfspr r10, SPRN_M_TWB /* Get level 1 table entry address */ - - /* If we are faulting a kernel address, we have to use the - * kernel page tables. - */ - andi. r11, r10, 0x0800 - beq 3f - lis r11, swapper_pg_dir@h - ori r11, r11, swapper_pg_dir@l - rlwimi r10, r11, 0, 2, 19 -3: - lwz r11, 0(r10) /* Get the level 1 entry */ - rlwinm. r10, r11,0,0,19 /* Extract page descriptor page address */ - beq 2f /* If zero, bail */ - - /* We have a pte table, so 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 */ - lwz r10, 0(r10) /* Get the pte */ - /* Insert the Guarded flag into the TWC from the Linux PTE. - * It is bit 27 of both the Linux PTE and the TWC - */ - rlwimi r11, r10, 0, 27, 27 - /* Insert the WriteThru flag into the TWC from the Linux PTE. - * It is bit 25 in the Linux PTE and bit 30 in the TWC - */ - rlwimi r11, r10, 32-5, 30, 30 - DO_8xx_CPU6(0x3b80, r3) - mtspr SPRN_MD_TWC, r11 - mfspr r11, SPRN_MD_TWC /* get the pte address again */ - - ori r10, r10, _PAGE_DIRTY | _PAGE_ACCESSED | _PAGE_HWWRITE - stw r10, 0(r11) /* and update pte in table */ - xori r10, r10, _PAGE_RW /* RW bit is inverted */ - - /* The Linux PTE won't go exactly into the MMU TLB. - * Software indicator bits 22 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 - 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 */ - lwz r11, 0(r0) - mtcr r11 - lwz r11, 4(r0) -#ifdef CONFIG_8xx_CPU6 - lwz r3, 8(r0) -#endif - rfi -2: mfspr r10, SPRN_M_TW /* Restore registers */ lwz r11, 0(r0) mtcr r11 |