diff options
Diffstat (limited to 'arch/powerpc/kernel/head_8xx.S')
| -rw-r--r-- | arch/powerpc/kernel/head_8xx.S | 150 |
1 files changed, 56 insertions, 94 deletions
diff --git a/arch/powerpc/kernel/head_8xx.S b/arch/powerpc/kernel/head_8xx.S index 7ee876d2adb5..fafff8dbd5d9 100644 --- a/arch/powerpc/kernel/head_8xx.S +++ b/arch/powerpc/kernel/head_8xx.S @@ -104,12 +104,15 @@ turn_on_mmu: * task's thread_struct. */ #define EXCEPTION_PROLOG \ - mtspr SPRN_SPRG_SCRATCH0,r10; \ - mtspr SPRN_SPRG_SCRATCH1,r11; \ - mfcr r10; \ + EXCEPTION_PROLOG_0; \ EXCEPTION_PROLOG_1; \ EXCEPTION_PROLOG_2 +#define EXCEPTION_PROLOG_0 \ + mtspr SPRN_SPRG_SCRATCH0,r10; \ + mtspr SPRN_SPRG_SCRATCH1,r11; \ + mfcr r10 + #define EXCEPTION_PROLOG_1 \ mfspr r11,SPRN_SRR1; /* check whether user or kernel */ \ andi. r11,r11,MSR_PR; \ @@ -145,6 +148,14 @@ turn_on_mmu: SAVE_2GPRS(7, r11) /* + * Exception exit code. + */ +#define EXCEPTION_EPILOG_0 \ + mtcr r10; \ + mfspr r10,SPRN_SPRG_SCRATCH0; \ + mfspr r11,SPRN_SPRG_SCRATCH1 + +/* * Note: code which follows this uses cr0.eq (set if from kernel), * r11, r12 (SRR0), and r9 (SRR1). * @@ -293,16 +304,8 @@ InstructionTLBMiss: #ifdef CONFIG_8xx_CPU6 stw r3, 8(r0) #endif - 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 + EXCEPTION_PROLOG_0 + mtspr SPRN_SPRG_SCRATCH2, r10 mfspr r10, SPRN_SRR0 /* Get effective address of fault */ #ifdef CONFIG_8xx_CPU15 addi r11, r10, 0x1000 @@ -359,18 +362,11 @@ InstructionTLBMiss: mtspr SPRN_MI_RPN, r10 /* Update TLB entry */ /* 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 + mfspr r10, SPRN_SPRG_SCRATCH2 + EXCEPTION_EPILOG_0 rfi 2: mfspr r11, SPRN_SRR1 @@ -381,19 +377,11 @@ InstructionTLBMiss: mtspr SPRN_SRR1, r11 /* 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 + mfspr r10, SPRN_SPRG_SCRATCH2 + EXCEPTION_EPILOG_0 b InstructionAccess . = 0x1200 @@ -401,16 +389,8 @@ DataStoreTLBMiss: #ifdef CONFIG_8xx_CPU6 stw r3, 8(r0) #endif - 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 + EXCEPTION_PROLOG_0 + mtspr SPRN_SPRG_SCRATCH2, r10 mfspr r10, SPRN_M_TWB /* Get level 1 table entry address */ /* If we are faulting a kernel address, we have to use the @@ -483,19 +463,12 @@ DataStoreTLBMiss: mtspr SPRN_MD_RPN, r10 /* Update TLB entry */ /* 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 + mtspr SPRN_DAR, r11 /* Tag DAR */ + mfspr r10, SPRN_SPRG_SCRATCH2 + EXCEPTION_EPILOG_0 rfi /* This is an instruction TLB error on the MPC8xx. This could be due @@ -507,35 +480,18 @@ InstructionTLBError: b InstructionAccess /* This is the data TLB error on the MPC8xx. This could be due to - * many reasons, including a dirty update to a pte. We can catch that - * one here, but anything else is an error. First, we track down the - * Linux pte. If it is valid, write access is allowed, but the - * page dirty bit is not set, we will set it and reload the TLB. For - * any other case, we bail out to a higher level function that can - * handle it. + * many reasons, including a dirty update to a pte. We bail out to + * a higher level function that can handle it. */ . = 0x1400 DataTLBError: -#ifdef CONFIG_8xx_CPU6 - stw r3, 8(r0) -#endif - DO_8xx_CPU6(0x3f80, r3) - mtspr SPRN_M_TW, r10 /* Save a couple of working registers */ - mfcr r10 - stw r10, 0(r0) - stw r11, 4(r0) + EXCEPTION_PROLOG_0 - mfspr r10, SPRN_DAR - cmpwi cr0, r10, 0x00f0 + mfspr r11, SPRN_DAR + cmpwi cr0, r11, 0x00f0 beq- FixupDAR /* must be a buggy dcbX, icbi insn. */ -DARFixed:/* Return from dcbx instruction bug workaround, r10 holds value of DAR */ - 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 +DARFixed:/* Return from dcbx instruction bug workaround */ + EXCEPTION_EPILOG_0 b DataAccess EXCEPTION(0x1500, Trap_15, unknown_exception, EXC_XFER_EE) @@ -559,11 +515,15 @@ DARFixed:/* Return from dcbx instruction bug workaround, r10 holds value of DAR /* This is the procedure to calculate the data EA for buggy dcbx,dcbi instructions * by decoding the registers used by the dcbx instruction and adding them. - * DAR is set to the calculated address and r10 also holds the EA on exit. + * DAR is set to the calculated address. */ /* define if you don't want to use self modifying code */ #define NO_SELF_MODIFYING_CODE FixupDAR:/* Entry point for dcbx workaround. */ +#ifdef CONFIG_8xx_CPU6 + stw r3, 8(r0) +#endif + mtspr SPRN_SPRG_SCRATCH2, r10 /* fetch instruction from memory. */ mfspr r10, SPRN_SRR0 andis. r11, r10, 0x8000 /* Address >= 0x80000000 */ @@ -579,16 +539,17 @@ FixupDAR:/* Entry point for dcbx workaround. */ 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 */ +#ifdef CONFIG_8xx_CPU6 + lwz r3, 8(r0) /* restore r3 from memory */ +#endif /* concat physical page address(r11) and page offset(r10) */ rlwimi r11, r10, 0, 20, 31 lwz r11,0(r11) /* Check if it really is a dcbx instruction. */ /* dcbt and dcbtst does not generate DTLB Misses/Errors, * no need to include them here */ - srwi r10, r11, 26 /* check if major OP code is 31 */ - cmpwi cr0, r10, 31 - bne- 141f - rlwinm r10, r11, 0, 21, 30 + xoris r10, r11, 0x7c00 /* check if major OP code is 31 */ + rlwinm r10, r10, 0, 21, 5 cmpwi cr0, r10, 2028 /* Is dcbz? */ beq+ 142f cmpwi cr0, r10, 940 /* Is dcbi? */ @@ -599,16 +560,13 @@ FixupDAR:/* Entry point for dcbx workaround. */ beq+ 142f cmpwi cr0, r10, 1964 /* Is icbi? */ beq+ 142f -141: mfspr r10, SPRN_DAR /* r10 must hold DAR at exit */ +141: mfspr r10,SPRN_SPRG_SCRATCH2 b DARFixed /* Nope, go back to normal TLB processing */ 144: mfspr r10, SPRN_DSISR rlwinm r10, r10,0,7,5 /* Clear store bit for buggy dcbst insn */ mtspr SPRN_DSISR, r10 142: /* continue, it was a dcbx, dcbi instruction. */ -#ifdef CONFIG_8xx_CPU6 - lwz r3, 8(r0) /* restore r3 from memory */ -#endif #ifndef NO_SELF_MODIFYING_CODE andis. r10,r11,0x1f /* test if reg RA is r0 */ li r10,modified_instr@l @@ -619,14 +577,15 @@ FixupDAR:/* Entry point for dcbx workaround. */ stw r11,0(r10) /* store add/and instruction */ dcbf 0,r10 /* flush new instr. to memory. */ icbi 0,r10 /* invalidate instr. cache line */ - lwz r11, 4(r0) /* restore r11 from memory */ - mfspr r10, SPRN_M_TW /* restore r10 from M_TW */ + mfspr r11, SPRN_SPRG_SCRATCH1 /* restore r11 */ + mfspr r10, SPRN_SPRG_SCRATCH0 /* restore r10 */ isync /* Wait until new instr is loaded from memory */ modified_instr: .space 4 /* this is where the add instr. is stored */ bne+ 143f subf r10,r0,r10 /* r10=r10-r0, only if reg RA is r0 */ 143: mtdar r10 /* store faulting EA in DAR */ + mfspr r10,SPRN_SPRG_SCRATCH2 b DARFixed /* Go back to normal TLB handling */ #else mfctr r10 @@ -680,13 +639,16 @@ modified_instr: mfdar r11 mtctr r11 /* restore ctr reg from DAR */ mtdar r10 /* save fault EA to DAR */ + mfspr r10,SPRN_SPRG_SCRATCH2 b DARFixed /* Go back to normal TLB handling */ /* special handling for r10,r11 since these are modified already */ -153: lwz r11, 4(r0) /* load r11 from memory */ - b 155f -154: mfspr r11, SPRN_M_TW /* load r10 from M_TW */ -155: add r10, r10, r11 /* add it */ +153: mfspr r11, SPRN_SPRG_SCRATCH1 /* load r11 from SPRN_SPRG_SCRATCH1 */ + add r10, r10, r11 /* add it */ + mfctr r11 /* restore r11 */ + b 151b +154: mfspr r11, SPRN_SPRG_SCRATCH0 /* load r10 from SPRN_SPRG_SCRATCH0 */ + add r10, r10, r11 /* add it */ mfctr r11 /* restore r11 */ b 151b #endif |