diff options
Diffstat (limited to 'arch/h8300/kernel/entry.S')
-rw-r--r-- | arch/h8300/kernel/entry.S | 393 |
1 files changed, 393 insertions, 0 deletions
diff --git a/arch/h8300/kernel/entry.S b/arch/h8300/kernel/entry.S new file mode 100644 index 0000000..ca74316 --- /dev/null +++ b/arch/h8300/kernel/entry.S @@ -0,0 +1,393 @@ +/* -*- mode: asm -*- + * + * linux/arch/h8300/platform/h8300h/entry.S + * + * Yoshinori Sato <ysato@users.sourceforge.jp> + * David McCullough <davidm@snapgear.com> + * + */ + +/* + * entry.S + * include exception/interrupt gateway + * system call entry + */ + +#include <linux/sys.h> +#include <asm/unistd.h> +#include <asm/setup.h> +#include <asm/segment.h> +#include <asm/linkage.h> +#include <asm/asm-offsets.h> +#include <asm/thread_info.h> +#include <asm/errno.h> + +#if defined(CONFIG_CPU_H8300H) +#define USERRET 8 +INTERRUPTS = 64 + .h8300h + .macro SHLL2 reg + shll.l \reg + shll.l \reg + .endm + .macro SHLR2 reg + shlr.l \reg + shlr.l \reg + .endm + .macro SAVEREGS + mov.l er0,@-sp + mov.l er1,@-sp + mov.l er2,@-sp + mov.l er3,@-sp + .endm + .macro RESTOREREGS + mov.l @sp+,er3 + mov.l @sp+,er2 + .endm + .macro SAVEEXR + .endm + .macro RESTOREEXR + .endm +#endif +#if defined(CONFIG_CPU_H8S) +#define USERRET 10 +#define USEREXR 8 +INTERRUPTS = 128 + .h8300s + .macro SHLL2 reg + shll.l #2,\reg + .endm + .macro SHLR2 reg + shlr.l #2,\reg + .endm + .macro SAVEREGS + stm.l er0-er3,@-sp + .endm + .macro RESTOREREGS + ldm.l @sp+,er2-er3 + .endm + .macro SAVEEXR + mov.w @(USEREXR:16,er0),r1 + mov.w r1,@(LEXR-LER3:16,sp) /* copy EXR */ + .endm + .macro RESTOREEXR + mov.w @(LEXR-LER1:16,sp),r1 /* restore EXR */ + mov.b r1l,r1h + mov.w r1,@(USEREXR:16,er0) + .endm +#endif + + +/* CPU context save/restore macros. */ + + .macro SAVE_ALL + mov.l er0,@-sp + stc ccr,r0l /* check kernel mode */ + btst #4,r0l + bne 5f + + /* user mode */ + mov.l sp,@SYMBOL_NAME(sw_usp) + mov.l @sp,er0 /* restore saved er0 */ + orc #0x10,ccr /* switch kernel stack */ + mov.l @SYMBOL_NAME(sw_ksp),sp + sub.l #(LRET-LORIG),sp /* allocate LORIG - LRET */ + SAVEREGS + mov.l @SYMBOL_NAME(sw_usp),er0 + mov.l @(USERRET:16,er0),er1 /* copy the RET addr */ + mov.l er1,@(LRET-LER3:16,sp) + SAVEEXR + + mov.l @(LORIG-LER3:16,sp),er0 + mov.l er0,@(LER0-LER3:16,sp) /* copy ER0 */ + mov.w e1,r1 /* e1 highbyte = ccr */ + and #0xef,r1h /* mask mode? flag */ + bra 6f +5: + /* kernel mode */ + mov.l @sp,er0 /* restore saved er0 */ + subs #2,sp /* set dummy ccr */ + SAVEREGS + mov.w @(LRET-LER3:16,sp),r1 /* copy old ccr */ +6: + mov.b r1h,r1l + mov.b #0,r1h + mov.w r1,@(LCCR-LER3:16,sp) /* set ccr */ + mov.l er6,@-sp /* syscall arg #6 */ + mov.l er5,@-sp /* syscall arg #5 */ + mov.l er4,@-sp /* syscall arg #4 */ + .endm /* r1 = ccr */ + + .macro RESTORE_ALL + mov.l @sp+,er4 + mov.l @sp+,er5 + mov.l @sp+,er6 + RESTOREREGS + mov.w @(LCCR-LER1:16,sp),r0 /* check kernel mode */ + btst #4,r0l + bne 7f + + orc #0x80,ccr + mov.l @SYMBOL_NAME(sw_usp),er0 + mov.l @(LER0-LER1:16,sp),er1 /* restore ER0 */ + mov.l er1,@er0 + RESTOREEXR + mov.w @(LCCR-LER1:16,sp),r1 /* restore the RET addr */ + mov.b r1l,r1h + mov.b @(LRET+1-LER1:16,sp),r1l + mov.w r1,e1 + mov.w @(LRET+2-LER1:16,sp),r1 + mov.l er1,@(USERRET:16,er0) + + mov.l @sp+,er1 + add.l #(LRET-LER1),sp /* remove LORIG - LRET */ + mov.l sp,@SYMBOL_NAME(sw_ksp) + andc #0xef,ccr /* switch to user mode */ + mov.l er0,sp + bra 8f +7: + mov.l @sp+,er1 + adds #4,sp + adds #2,sp +8: + mov.l @sp+,er0 + adds #4,sp /* remove the sw created LVEC */ + rte + .endm + +.globl SYMBOL_NAME(system_call) +.globl SYMBOL_NAME(ret_from_exception) +.globl SYMBOL_NAME(ret_from_fork) +.globl SYMBOL_NAME(ret_from_interrupt) +.globl SYMBOL_NAME(interrupt_redirect_table) +.globl SYMBOL_NAME(sw_ksp),SYMBOL_NAME(sw_usp) +.globl SYMBOL_NAME(resume) +.globl SYMBOL_NAME(interrupt_entry) +.globl SYMBOL_NAME(trace_break) + +#if defined(CONFIG_ROMKERNEL) + .section .int_redirect,"ax" +SYMBOL_NAME_LABEL(interrupt_redirect_table) +#if defined(CONFIG_CPU_H8300H) + .rept 7 + .long 0 + .endr +#endif +#if defined(CONFIG_CPU_H8S) + .rept 5 + .long 0 + .endr + jmp @SYMBOL_NAME(trace_break) + .long 0 +#endif + + jsr @SYMBOL_NAME(interrupt_entry) /* NMI */ + jmp @SYMBOL_NAME(system_call) /* TRAPA #0 (System call) */ + .long 0 + .long 0 + jmp @SYMBOL_NAME(trace_break) /* TRAPA #3 (breakpoint) */ + .rept INTERRUPTS-12 + jsr @SYMBOL_NAME(interrupt_entry) + .endr +#endif +#if defined(CONFIG_RAMKERNEL) +.globl SYMBOL_NAME(interrupt_redirect_table) + .section .bss +SYMBOL_NAME_LABEL(interrupt_redirect_table) + .space 4 +#endif + + .section .text + .align 2 +SYMBOL_NAME_LABEL(interrupt_entry) + SAVE_ALL + mov.l sp,er0 + add.l #LVEC,er0 + btst #4,r1l + bne 1f + /* user LVEC */ + mov.l @SYMBOL_NAME(sw_usp),er0 + adds #4,er0 +1: + mov.l @er0,er0 /* LVEC address */ +#if defined(CONFIG_ROMKERNEL) + sub.l #SYMBOL_NAME(interrupt_redirect_table),er0 +#endif +#if defined(CONFIG_RAMKERNEL) + mov.l @SYMBOL_NAME(interrupt_redirect_table),er1 + sub.l er1,er0 +#endif + SHLR2 er0 + dec.l #1,er0 + mov.l sp,er1 + subs #4,er1 /* adjust ret_pc */ + jsr @SYMBOL_NAME(do_IRQ) + jmp @SYMBOL_NAME(ret_from_interrupt) + +SYMBOL_NAME_LABEL(system_call) + subs #4,sp /* dummy LVEC */ + SAVE_ALL + andc #0x7f,ccr + mov.l er0,er4 + + /* save top of frame */ + mov.l sp,er0 + jsr @SYMBOL_NAME(set_esp0) + mov.l sp,er2 + and.w #0xe000,r2 + mov.b @((TI_FLAGS+3-(TIF_SYSCALL_TRACE >> 3)):16,er2),r2l + btst #(TIF_SYSCALL_TRACE & 7),r2l + beq 1f + jsr @SYMBOL_NAME(do_syscall_trace) +1: + cmp.l #NR_syscalls,er4 + bcc badsys + SHLL2 er4 + mov.l #SYMBOL_NAME(sys_call_table),er0 + add.l er4,er0 + mov.l @er0,er4 + beq SYMBOL_NAME(ret_from_exception):16 + mov.l @(LER1:16,sp),er0 + mov.l @(LER2:16,sp),er1 + mov.l @(LER3:16,sp),er2 + jsr @er4 + mov.l er0,@(LER0:16,sp) /* save the return value */ + mov.l sp,er2 + and.w #0xe000,r2 + mov.b @((TI_FLAGS+3-(TIF_SYSCALL_TRACE >> 3)):16,er2),r2l + btst #(TIF_SYSCALL_TRACE & 7),r2l + beq 2f + jsr @SYMBOL_NAME(do_syscall_trace) +2: +#if defined(CONFIG_SYSCALL_PRINT) + jsr @SYMBOL_NAME(syscall_print) +#endif + orc #0x80,ccr + bra resume_userspace + +badsys: + mov.l #-ENOSYS,er0 + mov.l er0,@(LER0:16,sp) + bra resume_userspace + +#if !defined(CONFIG_PREEMPT) +#define resume_kernel restore_all +#endif + +SYMBOL_NAME_LABEL(ret_from_exception) +#if defined(CONFIG_PREEMPT) + orc #0x80,ccr +#endif +SYMBOL_NAME_LABEL(ret_from_interrupt) + mov.b @(LCCR+1:16,sp),r0l + btst #4,r0l + bne resume_kernel:8 /* return from kernel */ +resume_userspace: + andc #0x7f,ccr + mov.l sp,er4 + and.w #0xe000,r4 /* er4 <- current thread info */ + mov.l @(TI_FLAGS:16,er4),er1 + and.l #_TIF_WORK_MASK,er1 + beq restore_all:8 +work_pending: + btst #TIF_NEED_RESCHED,r1l + bne work_resched:8 + /* work notifysig */ + mov.l sp,er0 + subs #4,er0 /* er0: pt_regs */ + jsr @SYMBOL_NAME(do_notify_resume) + bra restore_all:8 +work_resched: + mov.l sp,er0 + jsr @SYMBOL_NAME(set_esp0) + jsr @SYMBOL_NAME(schedule) + bra resume_userspace:8 +restore_all: + RESTORE_ALL /* Does RTE */ + +#if defined(CONFIG_PREEMPT) +resume_kernel: + mov.l @(TI_PRE_COUNT:16,er4),er0 + bne restore_all:8 +need_resched: + mov.l @(TI_FLAGS:16,er4),er0 + btst #TIF_NEED_RESCHED,r0l + beq restore_all:8 + mov.b @(LCCR+1:16,sp),r0l /* Interrupt Enabled? */ + bmi restore_all:8 + mov.l #PREEMPT_ACTIVE,er0 + mov.l er0,@(TI_PRE_COUNT:16,er4) + andc #0x7f,ccr + mov.l sp,er0 + jsr @SYMBOL_NAME(set_esp0) + jsr @SYMBOL_NAME(schedule) + orc #0x80,ccr + bra need_resched:8 +#endif + +SYMBOL_NAME_LABEL(ret_from_fork) + mov.l er2,er0 + jsr @SYMBOL_NAME(schedule_tail) + jmp @SYMBOL_NAME(ret_from_exception) + +SYMBOL_NAME_LABEL(resume) + /* + * Beware - when entering resume, offset of tss is in d1, + * prev (the current task) is in a0, next (the new task) + * is in a1 and d2.b is non-zero if the mm structure is + * shared between the tasks, so don't change these + * registers until their contents are no longer needed. + */ + + /* save sr */ + sub.w r3,r3 + stc ccr,r3l + mov.w r3,@(THREAD_CCR+2:16,er0) + + /* disable interrupts */ + orc #0x80,ccr + mov.l @SYMBOL_NAME(sw_usp),er3 + mov.l er3,@(THREAD_USP:16,er0) + mov.l sp,@(THREAD_KSP:16,er0) + + /* Skip address space switching if they are the same. */ + /* FIXME: what did we hack out of here, this does nothing! */ + + mov.l @(THREAD_USP:16,er1),er0 + mov.l er0,@SYMBOL_NAME(sw_usp) + mov.l @(THREAD_KSP:16,er1),sp + + /* restore status register */ + mov.w @(THREAD_CCR+2:16,er1),r3 + + ldc r3l,ccr + rts + +SYMBOL_NAME_LABEL(trace_break) + subs #4,sp + SAVE_ALL + sub.l er1,er1 + dec.l #1,er1 + mov.l er1,@(LORIG,sp) + mov.l sp,er0 + jsr @SYMBOL_NAME(set_esp0) + mov.l @SYMBOL_NAME(sw_usp),er0 + mov.l @er0,er1 + mov.w @(-2:16,er1),r2 + cmp.w #0x5730,r2 + beq 1f + subs #2,er1 + mov.l er1,@er0 +1: + and.w #0xff,e1 + mov.l er1,er0 + jsr @SYMBOL_NAME(trace_trap) + jmp @SYMBOL_NAME(ret_from_exception) + + .section .bss +SYMBOL_NAME_LABEL(sw_ksp) + .space 4 +SYMBOL_NAME_LABEL(sw_usp) + .space 4 + + .end |