diff options
Diffstat (limited to 'arch/powerpc/kernel/head_44x.S')
| -rw-r--r-- | arch/powerpc/kernel/head_44x.S | 208 |
1 files changed, 160 insertions, 48 deletions
diff --git a/arch/powerpc/kernel/head_44x.S b/arch/powerpc/kernel/head_44x.S index cbb3436b592..c334f53453f 100644 --- a/arch/powerpc/kernel/head_44x.S +++ b/arch/powerpc/kernel/head_44x.S @@ -61,15 +61,37 @@ _ENTRY(_start); * of abatron_pteptrs */ nop + mr r31,r3 /* save device tree ptr */ + li r24,0 /* CPU number */ + +#ifdef CONFIG_RELOCATABLE /* - * Save parameters we are passed + * Relocate ourselves to the current runtime address. + * This is called only by the Boot CPU. + * "relocate" is called with our current runtime virutal + * address. + * r21 will be loaded with the physical runtime address of _stext */ - mr r31,r3 - mr r30,r4 - mr r29,r5 - mr r28,r6 - mr r27,r7 - li r24,0 /* CPU number */ + bl 0f /* Get our runtime address */ +0: mflr r21 /* Make it accessible */ + addis r21,r21,(_stext - 0b)@ha + addi r21,r21,(_stext - 0b)@l /* Get our current runtime base */ + + /* + * We have the runtime (virutal) address of our base. + * We calculate our shift of offset from a 256M page. + * We could map the 256M page we belong to at PAGE_OFFSET and + * get going from there. + */ + lis r4,KERNELBASE@h + ori r4,r4,KERNELBASE@l + rlwinm r6,r21,0,4,31 /* r6 = PHYS_START % 256M */ + rlwinm r5,r4,0,4,31 /* r5 = KERNELBASE % 256M */ + subf r3,r5,r6 /* r3 = r6 - r5 */ + add r3,r4,r3 /* Required Virutal Address */ + + bl relocate +#endif bl init_cpu_state @@ -93,14 +115,94 @@ _ENTRY(_start); bl early_init +#ifdef CONFIG_RELOCATABLE + /* + * Relocatable kernel support based on processing of dynamic + * relocation entries. + * + * r25 will contain RPN/ERPN for the start address of memory + * r21 will contain the current offset of _stext + */ + lis r3,kernstart_addr@ha + la r3,kernstart_addr@l(r3) + + /* + * Compute the kernstart_addr. + * kernstart_addr => (r6,r8) + * kernstart_addr & ~0xfffffff => (r6,r7) + */ + rlwinm r6,r25,0,28,31 /* ERPN. Bits 32-35 of Address */ + rlwinm r7,r25,0,0,3 /* RPN - assuming 256 MB page size */ + rlwinm r8,r21,0,4,31 /* r8 = (_stext & 0xfffffff) */ + or r8,r7,r8 /* Compute the lower 32bit of kernstart_addr */ + + /* Store kernstart_addr */ + stw r6,0(r3) /* higher 32bit */ + stw r8,4(r3) /* lower 32bit */ + + /* + * Compute the virt_phys_offset : + * virt_phys_offset = stext.run - kernstart_addr + * + * stext.run = (KERNELBASE & ~0xfffffff) + (kernstart_addr & 0xfffffff) + * When we relocate, we have : + * + * (kernstart_addr & 0xfffffff) = (stext.run & 0xfffffff) + * + * hence: + * virt_phys_offset = (KERNELBASE & ~0xfffffff) - (kernstart_addr & ~0xfffffff) + * + */ + + /* KERNELBASE&~0xfffffff => (r4,r5) */ + li r4, 0 /* higer 32bit */ + lis r5,KERNELBASE@h + rlwinm r5,r5,0,0,3 /* Align to 256M, lower 32bit */ + + /* + * 64bit subtraction. + */ + subfc r5,r7,r5 + subfe r4,r6,r4 + + /* Store virt_phys_offset */ + lis r3,virt_phys_offset@ha + la r3,virt_phys_offset@l(r3) + + stw r4,0(r3) + stw r5,4(r3) + +#elif defined(CONFIG_DYNAMIC_MEMSTART) + /* + * Mapping based, page aligned dynamic kernel loading. + * + * r25 will contain RPN/ERPN for the start address of memory + * + * Add the difference between KERNELBASE and PAGE_OFFSET to the + * start of physical memory to get kernstart_addr. + */ + lis r3,kernstart_addr@ha + la r3,kernstart_addr@l(r3) + + lis r4,KERNELBASE@h + ori r4,r4,KERNELBASE@l + lis r5,PAGE_OFFSET@h + ori r5,r5,PAGE_OFFSET@l + subf r4,r5,r4 + + rlwinm r6,r25,0,28,31 /* ERPN */ + rlwinm r7,r25,0,0,3 /* RPN - assuming 256 MB page size */ + add r7,r7,r4 + + stw r6,0(r3) + stw r7,4(r3) +#endif + /* * Decide what sort of machine this is and initialize the MMU. */ - mr r3,r31 - mr r4,r30 - mr r5,r29 - mr r6,r28 - mr r7,r27 + li r3,0 + mr r4,r31 bl machine_init bl MMU_init @@ -146,10 +248,11 @@ _ENTRY(_start); interrupt_base: /* Critical Input Interrupt */ - CRITICAL_EXCEPTION(0x0100, CriticalInput, unknown_exception) + CRITICAL_EXCEPTION(0x0100, CRITICAL, CriticalInput, unknown_exception) /* Machine Check Interrupt */ - CRITICAL_EXCEPTION(0x0200, MachineCheck, machine_check_exception) + CRITICAL_EXCEPTION(0x0200, MACHINE_CHECK, MachineCheck, \ + machine_check_exception) MCHECK_EXCEPTION(0x0210, MachineCheckA, machine_check_exception) /* Data Storage Interrupt */ @@ -159,7 +262,8 @@ interrupt_base: INSTRUCTION_STORAGE_EXCEPTION /* External Input Interrupt */ - EXCEPTION(0x0500, ExternalInput, do_IRQ, EXC_XFER_LITE) + EXCEPTION(0x0500, BOOKE_INTERRUPT_EXTERNAL, ExternalInput, \ + do_IRQ, EXC_XFER_LITE) /* Alignment Interrupt */ ALIGNMENT_EXCEPTION @@ -171,29 +275,32 @@ interrupt_base: #ifdef CONFIG_PPC_FPU FP_UNAVAILABLE_EXCEPTION #else - EXCEPTION(0x2010, FloatingPointUnavailable, unknown_exception, EXC_XFER_EE) + EXCEPTION(0x2010, BOOKE_INTERRUPT_FP_UNAVAIL, \ + FloatingPointUnavailable, unknown_exception, EXC_XFER_EE) #endif /* System Call Interrupt */ START_EXCEPTION(SystemCall) - NORMAL_EXCEPTION_PROLOG + NORMAL_EXCEPTION_PROLOG(BOOKE_INTERRUPT_SYSCALL) EXC_XFER_EE_LITE(0x0c00, DoSyscall) - /* Auxillary Processor Unavailable Interrupt */ - EXCEPTION(0x2020, AuxillaryProcessorUnavailable, unknown_exception, EXC_XFER_EE) + /* Auxiliary Processor Unavailable Interrupt */ + EXCEPTION(0x2020, BOOKE_INTERRUPT_AP_UNAVAIL, \ + AuxillaryProcessorUnavailable, unknown_exception, EXC_XFER_EE) /* Decrementer Interrupt */ DECREMENTER_EXCEPTION /* Fixed Internal Timer Interrupt */ /* TODO: Add FIT support */ - EXCEPTION(0x1010, FixedIntervalTimer, unknown_exception, EXC_XFER_EE) + EXCEPTION(0x1010, BOOKE_INTERRUPT_FIT, FixedIntervalTimer, \ + unknown_exception, EXC_XFER_EE) /* Watchdog Timer Interrupt */ /* TODO: Add watchdog support */ #ifdef CONFIG_BOOKE_WDT - CRITICAL_EXCEPTION(0x1020, WatchdogTimer, WatchdogException) + CRITICAL_EXCEPTION(0x1020, WATCHDOG, WatchdogTimer, WatchdogException) #else - CRITICAL_EXCEPTION(0x1020, WatchdogTimer, unknown_exception) + CRITICAL_EXCEPTION(0x1020, WATCHDOG, WatchdogTimer, unknown_exception) #endif /* Data TLB Error Interrupt */ @@ -662,6 +769,8 @@ finish_tlb_load_47x: */ DEBUG_CRIT_EXCEPTION +interrupt_end: + /* * Global functions */ @@ -675,24 +784,6 @@ _GLOBAL(__fixup_440A_mcheck) sync blr -/* - * extern void giveup_altivec(struct task_struct *prev) - * - * The 44x core does not have an AltiVec unit. - */ -_GLOBAL(giveup_altivec) - blr - -/* - * extern void giveup_fpu(struct task_struct *prev) - * - * The 44x core does not have an FPU. - */ -#ifndef CONFIG_PPC_FPU -_GLOBAL(giveup_fpu) - blr -#endif - _GLOBAL(set_context) #ifdef CONFIG_BDI_SWITCH @@ -718,6 +809,8 @@ _GLOBAL(init_cpu_state) /* We use the PVR to differenciate 44x cores from 476 */ mfspr r3,SPRN_PVR srwi r3,r3,16 + cmplwi cr0,r3,PVR_476FPE@h + beq head_start_47x cmplwi cr0,r3,PVR_476@h beq head_start_47x cmplwi cr0,r3,PVR_476_ISS@h @@ -786,12 +879,29 @@ skpinv: addi r4,r4,1 /* Increment */ /* * Configure and load pinned entry into TLB slot 63. */ +#ifdef CONFIG_NONSTATIC_KERNEL + /* + * In case of a NONSTATIC_KERNEL we reuse the TLB XLAT + * entries of the initial mapping set by the boot loader. + * The XLAT entry is stored in r25 + */ + + /* Read the XLAT entry for our current mapping */ + tlbre r25,r23,PPC44x_TLB_XLAT + + lis r3,KERNELBASE@h + ori r3,r3,KERNELBASE@l + + /* Use our current RPN entry */ + mr r4,r25 +#else 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 */ +#endif /* Load the kernel PID = 0 */ li r0,0 @@ -1001,9 +1111,6 @@ clear_utlb_entry: 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 @@ -1013,9 +1120,8 @@ clear_utlb_entry: clrrwi r3,r3,12 /* Mask off the effective page number */ ori r3,r3,PPC47x_TLB0_VALID | PPC47x_TLB0_256M - /* Word 1 */ - clrrwi r4,r4,12 /* Mask off the real page number */ - /* ERPN is 0 for first 4GB page */ + /* Word 1 - use r25. RPN is the same as the original entry */ + /* Word 2 */ li r5,0 ori r5,r5,PPC47x_TLB2_S_RWX @@ -1026,7 +1132,7 @@ clear_utlb_entry: /* We write to way 0 and bolted 0 */ lis r0,0x8800 tlbwe r3,r0,0 - tlbwe r4,r0,1 + tlbwe r25,r0,1 tlbwe r5,r0,2 /* @@ -1124,7 +1230,13 @@ head_start_common: lis r4,interrupt_base@h /* IVPR only uses the high 16-bits */ mtspr SPRN_IVPR,r4 - addis r22,r22,KERNELBASE@h + /* + * If the kernel was loaded at a non-zero 256 MB page, we need to + * mask off the most significant 4 bits to get the relative address + * from the start of physical memory + */ + rlwinm r22,r22,0,4,31 + addis r22,r22,PAGE_OFFSET@h mtlr r22 isync blr |