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Diffstat (limited to '')
| -rw-r--r-- | arch/sh/kernel/cpu/sh2a/entry.S | 247 |
1 files changed, 247 insertions, 0 deletions
diff --git a/arch/sh/kernel/cpu/sh2a/entry.S b/arch/sh/kernel/cpu/sh2a/entry.S new file mode 100644 index 000000000..9f11fc8b5 --- /dev/null +++ b/arch/sh/kernel/cpu/sh2a/entry.S @@ -0,0 +1,247 @@ +/* SPDX-License-Identifier: GPL-2.0 + * + * arch/sh/kernel/cpu/sh2a/entry.S + * + * The SH-2A exception entry + * + * Copyright (C) 2008 Yoshinori Sato + * Based on arch/sh/kernel/cpu/sh2/entry.S + */ + +#include <linux/linkage.h> +#include <asm/asm-offsets.h> +#include <asm/thread_info.h> +#include <cpu/mmu_context.h> +#include <asm/unistd.h> +#include <asm/errno.h> +#include <asm/page.h> + +/* Offsets to the stack */ +OFF_R0 = 0 /* Return value. New ABI also arg4 */ +OFF_R1 = 4 /* New ABI: arg5 */ +OFF_R2 = 8 /* New ABI: arg6 */ +OFF_R3 = 12 /* New ABI: syscall_nr */ +OFF_R4 = 16 /* New ABI: arg0 */ +OFF_R5 = 20 /* New ABI: arg1 */ +OFF_R6 = 24 /* New ABI: arg2 */ +OFF_R7 = 28 /* New ABI: arg3 */ +OFF_SP = (15*4) +OFF_PC = (16*4) +OFF_SR = (16*4+2*4) +OFF_TRA = (16*4+6*4) + +#include <asm/entry-macros.S> + +ENTRY(exception_handler) + ! stack + ! r0 <- point sp + ! r1 + ! pc + ! sr + ! r0 = temporary + ! r1 = vector (pseudo EXPEVT / INTEVT / TRA) + mov.l r2,@-sp + cli + mov.l $cpu_mode,r2 + bld.b #6,@(0,r2) !previus SR.MD + bst.b #6,@(4*4,r15) !set cpu mode to SR.MD + bt 1f + ! switch to kernel mode + bset.b #6,@(0,r2) !set SR.MD + mov.l $current_thread_info,r2 + mov.l @r2,r2 + mov #(THREAD_SIZE >> 8),r0 + shll8 r0 + add r2,r0 ! r0 = kernel stack tail + mov r15,r2 ! r2 = user stack top + mov r0,r15 ! switch kernel stack + mov.l r1,@-r15 ! TRA + sts.l macl, @-r15 + sts.l mach, @-r15 + stc.l gbr, @-r15 + mov.l @(4*4,r2),r0 + mov.l r0,@-r15 ! original SR + sts.l pr,@-r15 + mov.l @(3*4,r2),r0 + mov.l r0,@-r15 ! original PC + mov r2,r0 + add #(3+2)*4,r0 ! rewind r0 - r3 + exception frame + lds r0,pr ! pr = original SP + movmu.l r3,@-r15 ! save regs + mov r2,r8 ! r8 = previus stack top + mov r1,r9 ! r9 = interrupt vector + ! restore previous stack + mov.l @r8+,r2 + mov.l @r8+,r0 + mov.l @r8+,r1 + bra 2f + movml.l r2,@-r15 +1: + ! in kernel exception + mov r15,r2 + add #-((OFF_TRA + 4) - OFF_PC) + 5*4,r15 + movmu.l r3,@-r15 + mov r2,r8 ! r8 = previous stack top + mov r1,r9 ! r9 = interrupt vector + ! restore exception frame & regs + mov.l @r8+,r2 ! old R2 + mov.l @r8+,r0 ! old R0 + mov.l @r8+,r1 ! old R1 + mov.l @r8+,r10 ! old PC + mov.l @r8+,r11 ! old SR + movml.l r2,@-r15 + mov.l r10,@(OFF_PC,r15) + mov.l r11,@(OFF_SR,r15) + mov.l r8,@(OFF_SP,r15) ! save old sp + mov r15,r8 + add #OFF_TRA + 4,r8 + mov.l r9,@-r8 + sts.l macl,@-r8 + sts.l mach,@-r8 + stc.l gbr,@-r8 + add #-4,r8 + sts.l pr,@-r8 +2: + ! dispatch exception / interrupt + mov #64,r8 + cmp/hs r8,r9 + bt interrupt_entry ! vec >= 64 is interrupt + mov #31,r8 + cmp/hs r8,r9 + bt trap_entry ! 64 > vec >= 31 is trap + + mov.l 4f,r8 + mov r9,r4 + shll2 r9 + add r9,r8 + mov.l @r8,r8 ! exception handler address + tst r8,r8 + bf 3f + mov.l 8f,r8 ! unhandled exception +3: + mov.l 5f,r10 + jmp @r8 + lds r10,pr + +interrupt_entry: + mov r9,r4 + mov r15,r5 + mov.l 7f,r8 + mov.l 6f,r9 + jmp @r8 + lds r9,pr + + .align 2 +4: .long exception_handling_table +5: .long ret_from_exception +6: .long ret_from_irq +7: .long do_IRQ +8: .long exception_error + +trap_entry: + mov #0x30,r8 + cmp/ge r8,r9 ! vector 0x1f-0x2f is systemcall + bt 1f + mov #0x1f,r9 ! convert to unified SH2/3/4 trap number +1: + shll2 r9 ! TRA + bra system_call ! jump common systemcall entry + mov r9,r8 + +#if defined(CONFIG_SH_STANDARD_BIOS) + /* Unwind the stack and jmp to the debug entry */ +ENTRY(sh_bios_handler) + mov r15,r0 + add #(22-4)*4-4,r0 + ldc.l @r0+,gbr + lds.l @r0+,mach + lds.l @r0+,macl + mov r15,r0 + mov.l @(OFF_SP,r0),r1 + mov.l @(OFF_SR,r2),r3 + mov.l r3,@-r1 + mov.l @(OFF_SP,r2),r3 + mov.l r3,@-r1 + mov r15,r0 + add #(22-4)*4-8,r0 + mov.l 1f,r2 + mov.l @r2,r2 + stc sr,r3 + mov.l r2,@r0 + mov.l r3,@(4,r0) + mov.l r1,@(8,r0) + movml.l @r15+,r14 + add #8,r15 + lds.l @r15+, pr + mov.l @r15+,r15 + rte + nop + .align 2 +1: .long gdb_vbr_vector +#endif /* CONFIG_SH_STANDARD_BIOS */ + +ENTRY(address_error_trap_handler) + mov r15,r4 ! regs + mov.l @(OFF_PC,r15),r6 ! pc + mov.l 1f,r0 + jmp @r0 + mov #0,r5 ! writeaccess is unknown + + .align 2 +1: .long do_address_error + +restore_all: + stc sr,r0 + or #0xf0,r0 + ldc r0,sr ! all interrupt block (same BL = 1) + ! restore special register + ! overlap exception frame + mov r15,r0 + add #17*4,r0 + lds.l @r0+,pr + add #4,r0 + ldc.l @r0+,gbr + lds.l @r0+,mach + lds.l @r0+,macl + mov r15,r0 + mov.l $cpu_mode,r2 + bld.b #6,@(OFF_SR,r15) + bst.b #6,@(0,r2) ! save CPU mode + mov.l @(OFF_SR,r0),r1 + shll2 r1 + shlr2 r1 ! clear MD bit + mov.l @(OFF_SP,r0),r2 + add #-8,r2 + mov.l r2,@(OFF_SP,r0) ! point exception frame top + mov.l r1,@(4,r2) ! set sr + mov.l @(OFF_PC,r0),r1 + mov.l r1,@r2 ! set pc + get_current_thread_info r0, r1 + mov.l $current_thread_info,r1 + mov.l r0,@r1 + movml.l @r15+,r14 + mov.l @r15,r15 + rte + nop + + .align 2 +$current_thread_info: + .long __current_thread_info +$cpu_mode: + .long __cpu_mode + +! common exception handler +#include "../../entry-common.S" + + .data +! cpu operation mode +! bit30 = MD (compatible SH3/4) +__cpu_mode: + .long 0x40000000 + + .section .bss +__current_thread_info: + .long 0 + +ENTRY(exception_handling_table) + .space 4*32 |