/* * 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/err.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_kernel_thread) bl schedule_tail # r4=struct task_struct *prev nop mv r4, r13 brl r12 j syscall_exit 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 sw r8, [r0, 16] # argument 5 from user r8 sw r9, [r0, 20] # argument 6 from user r9 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 bgeu illegal_syscall slli r8, r27, 2 # get syscall routine la r11, sys_call_table add r11, r11, r8 lw r10, [r11] # get syscall entry cmpz.c r10 beq illegal_syscall 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, -MAX_ERRNO - 1 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, -MAX_ERRNO - 1 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 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_rt_sigreturn) mv r4, r0 la r8, score_rt_sigreturn br r8