diff options
Diffstat (limited to 'arch/powerpc/kernel/head_44x.S')
| -rw-r--r-- | arch/powerpc/kernel/head_44x.S | 330 |
1 files changed, 171 insertions, 159 deletions
diff --git a/arch/powerpc/kernel/head_44x.S b/arch/powerpc/kernel/head_44x.S index 711368b993f..39be049a785 100644 --- a/arch/powerpc/kernel/head_44x.S +++ b/arch/powerpc/kernel/head_44x.S @@ -69,165 +69,7 @@ _ENTRY(_start); mr r27,r7 li r24,0 /* CPU number */ -/* - * In case the firmware didn't do it, we apply some workarounds - * that are good for all 440 core variants here - */ - mfspr r3,SPRN_CCR0 - rlwinm r3,r3,0,0,27 /* disable icache prefetch */ - isync - mtspr SPRN_CCR0,r3 - isync - sync - -/* - * Set up the initial MMU state - * - * We are still executing code at the virtual address - * mappings set by the firmware for the base of RAM. - * - * We first invalidate all TLB entries but the one - * we are running from. We then load the KERNELBASE - * mappings so we can begin to use kernel addresses - * natively and so the interrupt vector locations are - * permanently pinned (necessary since Book E - * implementations always have translation enabled). - * - * TODO: Use the known TLB entry we are running from to - * determine which physical region we are located - * in. This can be used to determine where in RAM - * (on a shared CPU system) or PCI memory space - * (on a DRAMless system) we are located. - * For now, we assume a perfect world which means - * we are located at the base of DRAM (physical 0). - */ - -/* - * Search TLB for entry that we are currently using. - * Invalidate all entries but the one we are using. - */ - /* Load our current PID->MMUCR TID and MSR IS->MMUCR STS */ - mfspr r3,SPRN_PID /* Get PID */ - mfmsr r4 /* Get MSR */ - andi. r4,r4,MSR_IS@l /* TS=1? */ - beq wmmucr /* If not, leave STS=0 */ - oris r3,r3,PPC44x_MMUCR_STS@h /* Set STS=1 */ -wmmucr: mtspr SPRN_MMUCR,r3 /* Put MMUCR */ - sync - - bl invstr /* Find our address */ -invstr: mflr r5 /* Make it accessible */ - tlbsx r23,0,r5 /* Find entry we are in */ - li r4,0 /* Start at TLB entry 0 */ - li r3,0 /* Set PAGEID inval value */ -1: cmpw r23,r4 /* Is this our entry? */ - beq skpinv /* If so, skip the inval */ - tlbwe r3,r4,PPC44x_TLB_PAGEID /* If not, inval the entry */ -skpinv: addi r4,r4,1 /* Increment */ - cmpwi r4,64 /* Are we done? */ - bne 1b /* If not, repeat */ - isync /* If so, context change */ - -/* - * Configure and load pinned entry into TLB slot 63. - */ - - lis r3,PAGE_OFFSET@h - ori r3,r3,PAGE_OFFSET@l - - /* Kernel is at the base of RAM */ - li r4, 0 /* Load the kernel physical address */ - - /* Load the kernel PID = 0 */ - li r0,0 - mtspr SPRN_PID,r0 - sync - - /* Initialize MMUCR */ - li r5,0 - mtspr SPRN_MMUCR,r5 - sync - - /* pageid fields */ - clrrwi r3,r3,10 /* Mask off the effective page number */ - ori r3,r3,PPC44x_TLB_VALID | PPC44x_TLB_256M - - /* xlat fields */ - clrrwi r4,r4,10 /* Mask off the real page number */ - /* ERPN is 0 for first 4GB page */ - - /* attrib fields */ - /* Added guarded bit to protect against speculative loads/stores */ - li r5,0 - ori r5,r5,(PPC44x_TLB_SW | PPC44x_TLB_SR | PPC44x_TLB_SX | PPC44x_TLB_G) - - li r0,63 /* TLB slot 63 */ - - tlbwe r3,r0,PPC44x_TLB_PAGEID /* Load the pageid fields */ - tlbwe r4,r0,PPC44x_TLB_XLAT /* Load the translation fields */ - tlbwe r5,r0,PPC44x_TLB_ATTRIB /* Load the attrib/access fields */ - - /* Force context change */ - mfmsr r0 - mtspr SPRN_SRR1, r0 - lis r0,3f@h - ori r0,r0,3f@l - mtspr SPRN_SRR0,r0 - sync - rfi - - /* If necessary, invalidate original entry we used */ -3: cmpwi r23,63 - beq 4f - li r6,0 - tlbwe r6,r23,PPC44x_TLB_PAGEID - isync - -4: -#ifdef CONFIG_PPC_EARLY_DEBUG_44x - /* Add UART mapping for early debug. */ - - /* pageid fields */ - lis r3,PPC44x_EARLY_DEBUG_VIRTADDR@h - ori r3,r3,PPC44x_TLB_VALID|PPC44x_TLB_TS|PPC44x_TLB_64K - - /* xlat fields */ - lis r4,CONFIG_PPC_EARLY_DEBUG_44x_PHYSLOW@h - ori r4,r4,CONFIG_PPC_EARLY_DEBUG_44x_PHYSHIGH - - /* attrib fields */ - li r5,(PPC44x_TLB_SW|PPC44x_TLB_SR|PPC44x_TLB_I|PPC44x_TLB_G) - li r0,62 /* TLB slot 0 */ - - tlbwe r3,r0,PPC44x_TLB_PAGEID - tlbwe r4,r0,PPC44x_TLB_XLAT - tlbwe r5,r0,PPC44x_TLB_ATTRIB - - /* Force context change */ - isync -#endif /* CONFIG_PPC_EARLY_DEBUG_44x */ - - /* Establish the interrupt vector offsets */ - SET_IVOR(0, CriticalInput); - SET_IVOR(1, MachineCheck); - SET_IVOR(2, DataStorage); - SET_IVOR(3, InstructionStorage); - SET_IVOR(4, ExternalInput); - SET_IVOR(5, Alignment); - SET_IVOR(6, Program); - SET_IVOR(7, FloatingPointUnavailable); - SET_IVOR(8, SystemCall); - SET_IVOR(9, AuxillaryProcessorUnavailable); - SET_IVOR(10, Decrementer); - SET_IVOR(11, FixedIntervalTimer); - SET_IVOR(12, WatchdogTimer); - SET_IVOR(13, DataTLBError); - SET_IVOR(14, InstructionTLBError); - SET_IVOR(15, DebugCrit); - - /* Establish the interrupt vector base */ - lis r4,interrupt_base@h /* IVPR only uses the high 16-bits */ - mtspr SPRN_IVPR,r4 + bl init_cpu_state /* * This is where the main kernel code starts. @@ -647,6 +489,176 @@ _GLOBAL(set_context) blr /* + * Init CPU state. This is called at boot time or for secondary CPUs + * to setup initial TLB entries, setup IVORs, etc... + */ +_GLOBAL(init_cpu_state) + mflr r22 +/* + * In case the firmware didn't do it, we apply some workarounds + * that are good for all 440 core variants here + */ + mfspr r3,SPRN_CCR0 + rlwinm r3,r3,0,0,27 /* disable icache prefetch */ + isync + mtspr SPRN_CCR0,r3 + isync + sync + +/* + * Set up the initial MMU state + * + * We are still executing code at the virtual address + * mappings set by the firmware for the base of RAM. + * + * We first invalidate all TLB entries but the one + * we are running from. We then load the KERNELBASE + * mappings so we can begin to use kernel addresses + * natively and so the interrupt vector locations are + * permanently pinned (necessary since Book E + * implementations always have translation enabled). + * + * TODO: Use the known TLB entry we are running from to + * determine which physical region we are located + * in. This can be used to determine where in RAM + * (on a shared CPU system) or PCI memory space + * (on a DRAMless system) we are located. + * For now, we assume a perfect world which means + * we are located at the base of DRAM (physical 0). + */ + +/* + * Search TLB for entry that we are currently using. + * Invalidate all entries but the one we are using. + */ + /* Load our current PID->MMUCR TID and MSR IS->MMUCR STS */ + mfspr r3,SPRN_PID /* Get PID */ + mfmsr r4 /* Get MSR */ + andi. r4,r4,MSR_IS@l /* TS=1? */ + beq wmmucr /* If not, leave STS=0 */ + oris r3,r3,PPC44x_MMUCR_STS@h /* Set STS=1 */ +wmmucr: mtspr SPRN_MMUCR,r3 /* Put MMUCR */ + sync + + bl invstr /* Find our address */ +invstr: mflr r5 /* Make it accessible */ + tlbsx r23,0,r5 /* Find entry we are in */ + li r4,0 /* Start at TLB entry 0 */ + li r3,0 /* Set PAGEID inval value */ +1: cmpw r23,r4 /* Is this our entry? */ + beq skpinv /* If so, skip the inval */ + tlbwe r3,r4,PPC44x_TLB_PAGEID /* If not, inval the entry */ +skpinv: addi r4,r4,1 /* Increment */ + cmpwi r4,64 /* Are we done? */ + bne 1b /* If not, repeat */ + isync /* If so, context change */ + +/* + * Configure and load pinned entry into TLB slot 63. + */ + + lis r3,PAGE_OFFSET@h + ori r3,r3,PAGE_OFFSET@l + + /* Kernel is at the base of RAM */ + li r4, 0 /* Load the kernel physical address */ + + /* Load the kernel PID = 0 */ + li r0,0 + mtspr SPRN_PID,r0 + sync + + /* Initialize MMUCR */ + li r5,0 + mtspr SPRN_MMUCR,r5 + sync + + /* pageid fields */ + clrrwi r3,r3,10 /* Mask off the effective page number */ + ori r3,r3,PPC44x_TLB_VALID | PPC44x_TLB_256M + + /* xlat fields */ + clrrwi r4,r4,10 /* Mask off the real page number */ + /* ERPN is 0 for first 4GB page */ + + /* attrib fields */ + /* Added guarded bit to protect against speculative loads/stores */ + li r5,0 + ori r5,r5,(PPC44x_TLB_SW | PPC44x_TLB_SR | PPC44x_TLB_SX | PPC44x_TLB_G) + + li r0,63 /* TLB slot 63 */ + + tlbwe r3,r0,PPC44x_TLB_PAGEID /* Load the pageid fields */ + tlbwe r4,r0,PPC44x_TLB_XLAT /* Load the translation fields */ + tlbwe r5,r0,PPC44x_TLB_ATTRIB /* Load the attrib/access fields */ + + /* Force context change */ + mfmsr r0 + mtspr SPRN_SRR1, r0 + lis r0,3f@h + ori r0,r0,3f@l + mtspr SPRN_SRR0,r0 + sync + rfi + + /* If necessary, invalidate original entry we used */ +3: cmpwi r23,63 + beq 4f + li r6,0 + tlbwe r6,r23,PPC44x_TLB_PAGEID + isync + +4: +#ifdef CONFIG_PPC_EARLY_DEBUG_44x + /* Add UART mapping for early debug. */ + + /* pageid fields */ + lis r3,PPC44x_EARLY_DEBUG_VIRTADDR@h + ori r3,r3,PPC44x_TLB_VALID|PPC44x_TLB_TS|PPC44x_TLB_64K + + /* xlat fields */ + lis r4,CONFIG_PPC_EARLY_DEBUG_44x_PHYSLOW@h + ori r4,r4,CONFIG_PPC_EARLY_DEBUG_44x_PHYSHIGH + + /* attrib fields */ + li r5,(PPC44x_TLB_SW|PPC44x_TLB_SR|PPC44x_TLB_I|PPC44x_TLB_G) + li r0,62 /* TLB slot 0 */ + + tlbwe r3,r0,PPC44x_TLB_PAGEID + tlbwe r4,r0,PPC44x_TLB_XLAT + tlbwe r5,r0,PPC44x_TLB_ATTRIB + + /* Force context change */ + isync +#endif /* CONFIG_PPC_EARLY_DEBUG_44x */ + + /* Establish the interrupt vector offsets */ + SET_IVOR(0, CriticalInput); + SET_IVOR(1, MachineCheck); + SET_IVOR(2, DataStorage); + SET_IVOR(3, InstructionStorage); + SET_IVOR(4, ExternalInput); + SET_IVOR(5, Alignment); + SET_IVOR(6, Program); + SET_IVOR(7, FloatingPointUnavailable); + SET_IVOR(8, SystemCall); + SET_IVOR(9, AuxillaryProcessorUnavailable); + SET_IVOR(10, Decrementer); + SET_IVOR(11, FixedIntervalTimer); + SET_IVOR(12, WatchdogTimer); + SET_IVOR(13, DataTLBError); + SET_IVOR(14, InstructionTLBError); + SET_IVOR(15, DebugCrit); + + /* Establish the interrupt vector base */ + lis r4,interrupt_base@h /* IVPR only uses the high 16-bits */ + mtspr SPRN_IVPR,r4 + + addis r22,r22,KERNELBASE@h + mtlr r22 + blr + +/* * We put a few things here that have to be page-aligned. This stuff * goes at the beginning of the data segment, which is page-aligned. */ |