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Diffstat (limited to 'arch/score/kernel/entry.S')
| -rw-r--r-- | arch/score/kernel/entry.S | 542 |
1 files changed, 542 insertions, 0 deletions
diff --git a/arch/score/kernel/entry.S b/arch/score/kernel/entry.S new file mode 100644 index 000000000000..6c6b7ea58afa --- /dev/null +++ b/arch/score/kernel/entry.S @@ -0,0 +1,542 @@ +/* + * arch/score/kernel/entry.S + * + * Score Processor version. + * + * Copyright (C) 2009 Sunplus Core Technology Co., Ltd. + * Chen Liqin <liqin.chen@sunplusct.com> + * Lennox Wu <lennox.wu@sunplusct.com> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, see the file COPYING, or write + * to the Free Software Foundation, Inc., + * 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA + */ + +#include <linux/errno.h> +#include <linux/init.h> +#include <linux/linkage.h> + +#include <asm/asmmacro.h> +#include <asm/thread_info.h> +#include <asm/unistd.h> + +/* + * disable interrupts. + */ +.macro disable_irq + mfcr r8, cr0 + srli r8, r8, 1 + slli r8, r8, 1 + mtcr r8, cr0 + nop + nop + nop + nop + nop +.endm + +/* + * enable interrupts. + */ +.macro enable_irq + mfcr r8, cr0 + ori r8, 1 + mtcr r8, cr0 + nop + nop + nop + nop + nop +.endm + +__INIT +ENTRY(debug_exception_vector) + nop! + nop! + nop! + nop! + nop! + nop! + nop! + nop! + +ENTRY(general_exception_vector) # should move to addr 0x200 + j general_exception + nop! + nop! + nop! + nop! + nop! + nop! + +ENTRY(interrupt_exception_vector) # should move to addr 0x210 + j interrupt_exception + nop! + nop! + nop! + nop! + nop! + nop! + + .section ".text", "ax" + .align 2; +general_exception: + mfcr r31, cr2 + nop + la r30, exception_handlers + andi r31, 0x1f # get ecr.exc_code + slli r31, r31, 2 + add r30, r30, r31 + lw r30, [r30] + br r30 + +interrupt_exception: + SAVE_ALL + mfcr r4, cr2 + nop + lw r16, [r28, TI_REGS] + sw r0, [r28, TI_REGS] + la r3, ret_from_irq + srli r4, r4, 18 # get ecr.ip[7:2], interrupt No. + mv r5, r0 + j do_IRQ + +ENTRY(handle_nmi) # NMI #1 + SAVE_ALL + mv r4, r0 + la r8, nmi_exception_handler + brl r8 + j restore_all + +ENTRY(handle_adelinsn) # AdEL-instruction #2 + SAVE_ALL + mfcr r8, cr6 + nop + nop + sw r8, [r0, PT_EMA] + mv r4, r0 + la r8, do_adelinsn + brl r8 + mv r4, r0 + j ret_from_exception + nop + +ENTRY(handle_ibe) # BusEL-instruction #5 + SAVE_ALL + mv r4, r0 + la r8, do_be + brl r8 + mv r4, r0 + j ret_from_exception + nop + +ENTRY(handle_pel) # P-EL #6 + SAVE_ALL + mv r4, r0 + la r8, do_pel + brl r8 + mv r4, r0 + j ret_from_exception + nop + +ENTRY(handle_ccu) # CCU #8 + SAVE_ALL + mv r4, r0 + la r8, do_ccu + brl r8 + mv r4, r0 + j ret_from_exception + nop + +ENTRY(handle_ri) # RI #9 + SAVE_ALL + mv r4, r0 + la r8, do_ri + brl r8 + mv r4, r0 + j ret_from_exception + nop + +ENTRY(handle_tr) # Trap #10 + SAVE_ALL + mv r4, r0 + la r8, do_tr + brl r8 + mv r4, r0 + j ret_from_exception + nop + +ENTRY(handle_adedata) # AdES-instruction #12 + SAVE_ALL + mfcr r8, cr6 + nop + nop + sw r8, [r0, PT_EMA] + mv r4, r0 + la r8, do_adedata + brl r8 + mv r4, r0 + j ret_from_exception + nop + +ENTRY(handle_cee) # CeE #16 + SAVE_ALL + mv r4, r0 + la r8, do_cee + brl r8 + mv r4, r0 + j ret_from_exception + nop + +ENTRY(handle_cpe) # CpE #17 + SAVE_ALL + mv r4, r0 + la r8, do_cpe + brl r8 + mv r4, r0 + j ret_from_exception + nop + +ENTRY(handle_dbe) # BusEL-data #18 + SAVE_ALL + mv r4, r0 + la r8, do_be + brl r8 + mv r4, r0 + j ret_from_exception + nop + +ENTRY(handle_reserved) # others + SAVE_ALL + mv r4, r0 + la r8, do_reserved + brl r8 + mv r4, r0 + j ret_from_exception + nop + +#ifndef CONFIG_PREEMPT +#define resume_kernel restore_all +#else +#define __ret_from_irq ret_from_exception +#endif + + .align 2 +#ifndef CONFIG_PREEMPT +ENTRY(ret_from_exception) + disable_irq # preempt stop + nop + j __ret_from_irq + nop +#endif + +ENTRY(ret_from_irq) + sw r16, [r28, TI_REGS] + +ENTRY(__ret_from_irq) + lw r8, [r0, PT_PSR] # returning to kernel mode? + andri.c r8, r8, KU_USER + beq resume_kernel + +resume_userspace: + disable_irq + lw r6, [r28, TI_FLAGS] # current->work + li r8, _TIF_WORK_MASK + and.c r8, r8, r6 # ignoring syscall_trace + bne work_pending + nop + j restore_all + nop + +#ifdef CONFIG_PREEMPT +resume_kernel: + disable_irq + lw r8, [r28, TI_PRE_COUNT] + cmpz.c r8 + bne r8, restore_all +need_resched: + lw r8, [r28, TI_FLAGS] + andri.c r9, r8, _TIF_NEED_RESCHED + beq restore_all + lw r8, [r28, PT_PSR] # Interrupts off? + andri.c r8, r8, 1 + beq restore_all + bl preempt_schedule_irq + nop + j need_resched + nop +#endif + +ENTRY(ret_from_fork) + bl schedule_tail # r4=struct task_struct *prev + +ENTRY(syscall_exit) + nop + disable_irq + lw r6, [r28, TI_FLAGS] # current->work + li r8, _TIF_WORK_MASK + and.c r8, r6, r8 + bne syscall_exit_work + +ENTRY(restore_all) # restore full frame + RESTORE_ALL_AND_RET + +work_pending: + andri.c r8, r6, _TIF_NEED_RESCHED # r6 is preloaded with TI_FLAGS + beq work_notifysig +work_resched: + bl schedule + nop + disable_irq + lw r6, [r28, TI_FLAGS] + li r8, _TIF_WORK_MASK + and.c r8, r6, r8 # is there any work to be done + # other than syscall tracing? + beq restore_all + andri.c r8, r6, _TIF_NEED_RESCHED + bne work_resched + +work_notifysig: + mv r4, r0 + li r5, 0 + bl do_notify_resume # r6 already loaded + nop + j resume_userspace + nop + +ENTRY(syscall_exit_work) + li r8, _TIF_SYSCALL_TRACE + and.c r8, r8, r6 # r6 is preloaded with TI_FLAGS + beq work_pending # trace bit set? + nop + enable_irq + mv r4, r0 + li r5, 1 + bl do_syscall_trace + nop + b resume_userspace + nop + +.macro save_context reg + sw r12, [\reg, THREAD_REG12]; + sw r13, [\reg, THREAD_REG13]; + sw r14, [\reg, THREAD_REG14]; + sw r15, [\reg, THREAD_REG15]; + sw r16, [\reg, THREAD_REG16]; + sw r17, [\reg, THREAD_REG17]; + sw r18, [\reg, THREAD_REG18]; + sw r19, [\reg, THREAD_REG19]; + sw r20, [\reg, THREAD_REG20]; + sw r21, [\reg, THREAD_REG21]; + sw r29, [\reg, THREAD_REG29]; + sw r2, [\reg, THREAD_REG2]; + sw r0, [\reg, THREAD_REG0] +.endm + +.macro restore_context reg + lw r12, [\reg, THREAD_REG12]; + lw r13, [\reg, THREAD_REG13]; + lw r14, [\reg, THREAD_REG14]; + lw r15, [\reg, THREAD_REG15]; + lw r16, [\reg, THREAD_REG16]; + lw r17, [\reg, THREAD_REG17]; + lw r18, [\reg, THREAD_REG18]; + lw r19, [\reg, THREAD_REG19]; + lw r20, [\reg, THREAD_REG20]; + lw r21, [\reg, THREAD_REG21]; + lw r29, [\reg, THREAD_REG29]; + lw r0, [\reg, THREAD_REG0]; + lw r2, [\reg, THREAD_REG2]; + lw r3, [\reg, THREAD_REG3] +.endm + +/* + * task_struct *resume(task_struct *prev, task_struct *next, + * struct thread_info *next_ti) + */ +ENTRY(resume) + mfcr r9, cr0 + nop + nop + sw r9, [r4, THREAD_PSR] + save_context r4 + sw r3, [r4, THREAD_REG3] + + mv r28, r6 + restore_context r5 + mv r8, r6 + addi r8, KERNEL_STACK_SIZE + subi r8, 32 + la r9, kernelsp; + sw r8, [r9]; + + mfcr r9, cr0 + ldis r7, 0x00ff + nop + and r9, r9, r7 + lw r6, [r5, THREAD_PSR] + not r7, r7 + and r6, r6, r7 + or r6, r6, r9 + mtcr r6, cr0 + nop; nop; nop; nop; nop + br r3 + +ENTRY(handle_sys) + SAVE_ALL + enable_irq + + sw r4, [r0, PT_ORIG_R4] #for restart syscall + sw r7, [r0, PT_ORIG_R7] #for restart syscall + sw r27, [r0, PT_IS_SYSCALL] # it from syscall + + lw r9, [r0, PT_EPC] # skip syscall on return + addi r9, 4 + sw r9, [r0, PT_EPC] + + cmpi.c r27, __NR_syscalls # check syscall number + bgtu illegal_syscall + + slli r8, r27, 3 # get syscall routine + la r11, sys_call_table + add r11, r11, r8 + lw r10, [r11] # get syscall entry + lw r11, [r11, 4] # get number of args + + cmpz.c r10 + beq illegal_syscall + + cmpi.c r11, 4 # more than 4 arguments? + bgtu stackargs + +stack_done: + lw r8, [r28, TI_FLAGS] + li r9, _TIF_SYSCALL_TRACE + and.c r8, r8, r9 + bne syscall_trace_entry + + brl r10 # Do The Real system call + + cmpi.c r4, 0 + blt 1f + ldi r8, 0 + sw r8, [r0, PT_R7] + b 2f +1: + cmpi.c r4, -EMAXERRNO-1 # -EMAXERRNO - 1=-1134 + ble 2f + ldi r8, 0x1; + sw r8, [r0, PT_R7] + neg r4, r4 +2: + sw r4, [r0, PT_R4] # save result + +syscall_return: + disable_irq + lw r6, [r28, TI_FLAGS] # current->work + li r8, _TIF_WORK_MASK + and.c r8, r6, r8 + bne syscall_return_work + j restore_all + +syscall_return_work: + j syscall_exit_work + +syscall_trace_entry: + mv r16, r10 + mv r4, r0 + li r5, 0 + bl do_syscall_trace + + mv r8, r16 + lw r4, [r0, PT_R4] # Restore argument registers + lw r5, [r0, PT_R5] + lw r6, [r0, PT_R6] + lw r7, [r0, PT_R7] + brl r8 + + li r8, -EMAXERRNO - 1 # error? + sw r8, [r0, PT_R7] # set error flag + + neg r4, r4 # error + sw r4, [r0, PT_R0] # set flag for syscall + # restarting +1: sw r4, [r0, PT_R2] # result + j syscall_exit + +stackargs: + lw r8, [r0, PT_R0] + andri.c r9, r8, 3 # test whether user sp is align a word + bne bad_stack + subi r11, 5 + slli r9, r11, 2 + add.c r9, r9, r8 + + bmi bad_stack + la r9, 3f # calculate branch address + slli r11, r11, 3 + sub r9, r9, r11 + br r9 + +2: lw r9, [r8, 20] # argument 6 from usp + sw r9, [r0, 20] + +3: lw r9, [r8, 16] # argument 5 from usp + sw r9, [r0, 16] + j stack_done + + .section __ex_table,"a" + .word 2b, bad_stack + .word 3b, bad_stack + .previous + + /* + * The stackpointer for a call with more than 4 arguments is bad. + * We probably should handle this case a bit more drastic. + */ +bad_stack: + neg r27, r27 # error + sw r27, [r0, PT_ORIG_R4] + sw r27, [r0, PT_R4] + ldi r8, 1 # set error flag + sw r8, [r0, PT_R7] + j syscall_return + +illegal_syscall: + ldi r4, -ENOSYS # error + sw r4, [r0, PT_ORIG_R4] + sw r4, [r0, PT_R4] + ldi r9, 1 # set error flag + sw r9, [r0, PT_R7] + j syscall_return + +ENTRY(sys_execve) + mv r4, r0 + la r8, score_execve + br r8 + +ENTRY(sys_clone) + mv r4, r0 + la r8, score_clone + br r8 + +ENTRY(sys_rt_sigreturn) + mv r4, r0 + la r8, score_rt_sigreturn + br r8 + +ENTRY(sys_sigaltstack) + mv r4, r0 + la r8, score_sigaltstack + br r8 |