diff options
Diffstat (limited to 'arch/powerpc/kernel/head_32.h')
| -rw-r--r-- | arch/powerpc/kernel/head_32.h | 203 |
1 files changed, 203 insertions, 0 deletions
diff --git a/arch/powerpc/kernel/head_32.h b/arch/powerpc/kernel/head_32.h new file mode 100644 index 000000000000..4a692553651f --- /dev/null +++ b/arch/powerpc/kernel/head_32.h @@ -0,0 +1,203 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef __HEAD_32_H__ +#define __HEAD_32_H__ + +#include <asm/ptrace.h> /* for STACK_FRAME_REGS_MARKER */ + +/* + * MSR_KERNEL is > 0x8000 on 4xx/Book-E since it include MSR_CE. + */ +.macro __LOAD_MSR_KERNEL r, x +.if \x >= 0x8000 + lis \r, (\x)@h + ori \r, \r, (\x)@l +.else + li \r, (\x) +.endif +.endm +#define LOAD_MSR_KERNEL(r, x) __LOAD_MSR_KERNEL r, x + +/* + * Exception entry code. This code runs with address translation + * turned off, i.e. using physical addresses. + * We assume sprg3 has the physical address of the current + * task's thread_struct. + */ + +.macro EXCEPTION_PROLOG + mtspr SPRN_SPRG_SCRATCH0,r10 + mtspr SPRN_SPRG_SCRATCH1,r11 + mfcr r10 + EXCEPTION_PROLOG_1 + EXCEPTION_PROLOG_2 +.endm + +.macro EXCEPTION_PROLOG_1 + mfspr r11,SPRN_SRR1 /* check whether user or kernel */ + andi. r11,r11,MSR_PR + tophys(r11,r1) /* use tophys(r1) if kernel */ + beq 1f + mfspr r11,SPRN_SPRG_THREAD + lwz r11,TASK_STACK-THREAD(r11) + addi r11,r11,THREAD_SIZE + tophys(r11,r11) +1: subi r11,r11,INT_FRAME_SIZE /* alloc exc. frame */ +.endm + +.macro EXCEPTION_PROLOG_2 + stw r10,_CCR(r11) /* save registers */ + stw r12,GPR12(r11) + stw r9,GPR9(r11) + mfspr r10,SPRN_SPRG_SCRATCH0 + stw r10,GPR10(r11) + mfspr r12,SPRN_SPRG_SCRATCH1 + stw r12,GPR11(r11) + mflr r10 + stw r10,_LINK(r11) + mfspr r12,SPRN_SRR0 + mfspr r9,SPRN_SRR1 + stw r1,GPR1(r11) + stw r1,0(r11) + tovirt(r1,r11) /* set new kernel sp */ +#ifdef CONFIG_40x + rlwinm r9,r9,0,14,12 /* clear MSR_WE (necessary?) */ +#else + li r10,MSR_KERNEL & ~(MSR_IR|MSR_DR) /* can take exceptions */ + MTMSRD(r10) /* (except for mach check in rtas) */ +#endif + stw r0,GPR0(r11) + lis r10,STACK_FRAME_REGS_MARKER@ha /* exception frame marker */ + addi r10,r10,STACK_FRAME_REGS_MARKER@l + stw r10,8(r11) + SAVE_4GPRS(3, r11) + SAVE_2GPRS(7, r11) +.endm + +.macro SYSCALL_ENTRY trapno + mfspr r12,SPRN_SPRG_THREAD + mfcr r10 + lwz r11,TASK_STACK-THREAD(r12) + mflr r9 + addi r11,r11,THREAD_SIZE - INT_FRAME_SIZE + rlwinm r10,r10,0,4,2 /* Clear SO bit in CR */ + tophys(r11,r11) + stw r10,_CCR(r11) /* save registers */ + mfspr r10,SPRN_SRR0 + stw r9,_LINK(r11) + mfspr r9,SPRN_SRR1 + stw r1,GPR1(r11) + stw r1,0(r11) + tovirt(r1,r11) /* set new kernel sp */ + stw r10,_NIP(r11) +#ifdef CONFIG_40x + rlwinm r9,r9,0,14,12 /* clear MSR_WE (necessary?) */ +#else + LOAD_MSR_KERNEL(r10, MSR_KERNEL & ~(MSR_IR|MSR_DR)) /* can take exceptions */ + MTMSRD(r10) /* (except for mach check in rtas) */ +#endif + lis r10,STACK_FRAME_REGS_MARKER@ha /* exception frame marker */ + stw r2,GPR2(r11) + addi r10,r10,STACK_FRAME_REGS_MARKER@l + stw r9,_MSR(r11) + li r2, \trapno + 1 + stw r10,8(r11) + stw r2,_TRAP(r11) + SAVE_GPR(0, r11) + SAVE_4GPRS(3, r11) + SAVE_2GPRS(7, r11) + addi r11,r1,STACK_FRAME_OVERHEAD + addi r2,r12,-THREAD + stw r11,PT_REGS(r12) +#if defined(CONFIG_40x) + /* Check to see if the dbcr0 register is set up to debug. Use the + internal debug mode bit to do this. */ + lwz r12,THREAD_DBCR0(r12) + andis. r12,r12,DBCR0_IDM@h +#endif + ACCOUNT_CPU_USER_ENTRY(r2, r11, r12) +#if defined(CONFIG_40x) + beq+ 3f + /* From user and task is ptraced - load up global dbcr0 */ + li r12,-1 /* clear all pending debug events */ + mtspr SPRN_DBSR,r12 + lis r11,global_dbcr0@ha + tophys(r11,r11) + addi r11,r11,global_dbcr0@l + lwz r12,0(r11) + mtspr SPRN_DBCR0,r12 + lwz r12,4(r11) + addi r12,r12,-1 + stw r12,4(r11) +#endif + +3: + tovirt(r2, r2) /* set r2 to current */ + lis r11, transfer_to_syscall@h + ori r11, r11, transfer_to_syscall@l +#ifdef CONFIG_TRACE_IRQFLAGS + /* + * If MSR is changing we need to keep interrupts disabled at this point + * otherwise we might risk taking an interrupt before we tell lockdep + * they are enabled. + */ + LOAD_MSR_KERNEL(r10, MSR_KERNEL) + rlwimi r10, r9, 0, MSR_EE +#else + LOAD_MSR_KERNEL(r10, MSR_KERNEL | MSR_EE) +#endif +#if defined(CONFIG_PPC_8xx) && defined(CONFIG_PERF_EVENTS) + mtspr SPRN_NRI, r0 +#endif + mtspr SPRN_SRR1,r10 + mtspr SPRN_SRR0,r11 + SYNC + RFI /* jump to handler, enable MMU */ +.endm + +/* + * Note: code which follows this uses cr0.eq (set if from kernel), + * r11, r12 (SRR0), and r9 (SRR1). + * + * Note2: once we have set r1 we are in a position to take exceptions + * again, and we could thus set MSR:RI at that point. + */ + +/* + * Exception vectors. + */ +#ifdef CONFIG_PPC_BOOK3S +#define START_EXCEPTION(n, label) \ + . = n; \ + DO_KVM n; \ +label: + +#else +#define START_EXCEPTION(n, label) \ + . = n; \ +label: + +#endif + +#define EXCEPTION(n, label, hdlr, xfer) \ + START_EXCEPTION(n, label) \ + EXCEPTION_PROLOG; \ + addi r3,r1,STACK_FRAME_OVERHEAD; \ + xfer(n, hdlr) + +#define EXC_XFER_TEMPLATE(hdlr, trap, msr, tfer, ret) \ + li r10,trap; \ + stw r10,_TRAP(r11); \ + LOAD_MSR_KERNEL(r10, msr); \ + bl tfer; \ + .long hdlr; \ + .long ret + +#define EXC_XFER_STD(n, hdlr) \ + EXC_XFER_TEMPLATE(hdlr, n, MSR_KERNEL, transfer_to_handler_full, \ + ret_from_except_full) + +#define EXC_XFER_LITE(n, hdlr) \ + EXC_XFER_TEMPLATE(hdlr, n+1, MSR_KERNEL, transfer_to_handler, \ + ret_from_except) + +#endif /* __HEAD_32_H__ */ |