diff options
Diffstat (limited to 'arch/microblaze/kernel/entry-nommu.S')
| -rw-r--r-- | arch/microblaze/kernel/entry-nommu.S | 622 |
1 files changed, 622 insertions, 0 deletions
diff --git a/arch/microblaze/kernel/entry-nommu.S b/arch/microblaze/kernel/entry-nommu.S new file mode 100644 index 000000000..7e394fc2c --- /dev/null +++ b/arch/microblaze/kernel/entry-nommu.S @@ -0,0 +1,622 @@ +/* + * Copyright (C) 2007-2009 Michal Simek <monstr@monstr.eu> + * Copyright (C) 2007-2009 PetaLogix + * Copyright (C) 2006 Atmark Techno, Inc. + * + * This file is subject to the terms and conditions of the GNU General Public + * License. See the file "COPYING" in the main directory of this archive + * for more details. + */ + +#include <linux/linkage.h> +#include <asm/thread_info.h> +#include <linux/errno.h> +#include <asm/entry.h> +#include <asm/asm-offsets.h> +#include <asm/registers.h> +#include <asm/unistd.h> +#include <asm/percpu.h> +#include <asm/signal.h> + +#if CONFIG_XILINX_MICROBLAZE0_USE_MSR_INSTR + .macro disable_irq + msrclr r0, MSR_IE + .endm + + .macro enable_irq + msrset r0, MSR_IE + .endm + + .macro clear_bip + msrclr r0, MSR_BIP + .endm +#else + .macro disable_irq + mfs r11, rmsr + andi r11, r11, ~MSR_IE + mts rmsr, r11 + .endm + + .macro enable_irq + mfs r11, rmsr + ori r11, r11, MSR_IE + mts rmsr, r11 + .endm + + .macro clear_bip + mfs r11, rmsr + andi r11, r11, ~MSR_BIP + mts rmsr, r11 + .endm +#endif + +ENTRY(_interrupt) + swi r1, r0, PER_CPU(ENTRY_SP) /* save the current sp */ + swi r11, r0, PER_CPU(R11_SAVE) /* temporarily save r11 */ + lwi r11, r0, PER_CPU(KM) /* load mode indicator */ + beqid r11, 1f + nop + brid 2f /* jump over */ + addik r1, r1, (-PT_SIZE) /* room for pt_regs (delay slot) */ +1: /* switch to kernel stack */ + lwi r1, r0, PER_CPU(CURRENT_SAVE) /* get the saved current */ + lwi r1, r1, TS_THREAD_INFO /* get the thread info */ + /* calculate kernel stack pointer */ + addik r1, r1, THREAD_SIZE - PT_SIZE +2: + swi r11, r1, PT_MODE /* store the mode */ + lwi r11, r0, PER_CPU(R11_SAVE) /* reload r11 */ + swi r2, r1, PT_R2 + swi r3, r1, PT_R3 + swi r4, r1, PT_R4 + swi r5, r1, PT_R5 + swi r6, r1, PT_R6 + swi r7, r1, PT_R7 + swi r8, r1, PT_R8 + swi r9, r1, PT_R9 + swi r10, r1, PT_R10 + swi r11, r1, PT_R11 + swi r12, r1, PT_R12 + swi r13, r1, PT_R13 + swi r14, r1, PT_R14 + swi r14, r1, PT_PC + swi r15, r1, PT_R15 + swi r16, r1, PT_R16 + swi r17, r1, PT_R17 + swi r18, r1, PT_R18 + swi r19, r1, PT_R19 + swi r20, r1, PT_R20 + swi r21, r1, PT_R21 + swi r22, r1, PT_R22 + swi r23, r1, PT_R23 + swi r24, r1, PT_R24 + swi r25, r1, PT_R25 + swi r26, r1, PT_R26 + swi r27, r1, PT_R27 + swi r28, r1, PT_R28 + swi r29, r1, PT_R29 + swi r30, r1, PT_R30 + swi r31, r1, PT_R31 + /* special purpose registers */ + mfs r11, rmsr + swi r11, r1, PT_MSR + mfs r11, rear + swi r11, r1, PT_EAR + mfs r11, resr + swi r11, r1, PT_ESR + mfs r11, rfsr + swi r11, r1, PT_FSR + /* reload original stack pointer and save it */ + lwi r11, r0, PER_CPU(ENTRY_SP) + swi r11, r1, PT_R1 + /* update mode indicator we are in kernel mode */ + addik r11, r0, 1 + swi r11, r0, PER_CPU(KM) + /* restore r31 */ + lwi r31, r0, PER_CPU(CURRENT_SAVE) + /* prepare the link register, the argument and jump */ + addik r15, r0, ret_from_intr - 8 + addk r6, r0, r15 + braid do_IRQ + add r5, r0, r1 + +ret_from_intr: + lwi r11, r1, PT_MODE + bneid r11, no_intr_resched + +3: + lwi r6, r31, TS_THREAD_INFO /* get thread info */ + lwi r19, r6, TI_FLAGS /* get flags in thread info */ + /* do an extra work if any bits are set */ + + andi r11, r19, _TIF_NEED_RESCHED + beqi r11, 1f + bralid r15, schedule + nop + bri 3b +1: andi r11, r19, _TIF_SIGPENDING | _TIF_NOTIFY_RESUME + beqid r11, no_intr_resched + addk r5, r1, r0 + bralid r15, do_notify_resume + addk r6, r0, r0 + bri 3b + +no_intr_resched: + /* Disable interrupts, we are now committed to the state restore */ + disable_irq + + /* save mode indicator */ + lwi r11, r1, PT_MODE + swi r11, r0, PER_CPU(KM) + + /* save r31 */ + swi r31, r0, PER_CPU(CURRENT_SAVE) +restore_context: + /* special purpose registers */ + lwi r11, r1, PT_FSR + mts rfsr, r11 + lwi r11, r1, PT_ESR + mts resr, r11 + lwi r11, r1, PT_EAR + mts rear, r11 + lwi r11, r1, PT_MSR + mts rmsr, r11 + + lwi r31, r1, PT_R31 + lwi r30, r1, PT_R30 + lwi r29, r1, PT_R29 + lwi r28, r1, PT_R28 + lwi r27, r1, PT_R27 + lwi r26, r1, PT_R26 + lwi r25, r1, PT_R25 + lwi r24, r1, PT_R24 + lwi r23, r1, PT_R23 + lwi r22, r1, PT_R22 + lwi r21, r1, PT_R21 + lwi r20, r1, PT_R20 + lwi r19, r1, PT_R19 + lwi r18, r1, PT_R18 + lwi r17, r1, PT_R17 + lwi r16, r1, PT_R16 + lwi r15, r1, PT_R15 + lwi r14, r1, PT_PC + lwi r13, r1, PT_R13 + lwi r12, r1, PT_R12 + lwi r11, r1, PT_R11 + lwi r10, r1, PT_R10 + lwi r9, r1, PT_R9 + lwi r8, r1, PT_R8 + lwi r7, r1, PT_R7 + lwi r6, r1, PT_R6 + lwi r5, r1, PT_R5 + lwi r4, r1, PT_R4 + lwi r3, r1, PT_R3 + lwi r2, r1, PT_R2 + lwi r1, r1, PT_R1 + rtid r14, 0 + nop + +ENTRY(_reset) + brai 0; + +ENTRY(_user_exception) + swi r1, r0, PER_CPU(ENTRY_SP) /* save the current sp */ + swi r11, r0, PER_CPU(R11_SAVE) /* temporarily save r11 */ + lwi r11, r0, PER_CPU(KM) /* load mode indicator */ + beqid r11, 1f /* Already in kernel mode? */ + nop + brid 2f /* jump over */ + addik r1, r1, (-PT_SIZE) /* Room for pt_regs (delay slot) */ +1: /* Switch to kernel stack */ + lwi r1, r0, PER_CPU(CURRENT_SAVE) /* get the saved current */ + lwi r1, r1, TS_THREAD_INFO /* get the thread info */ + /* calculate kernel stack pointer */ + addik r1, r1, THREAD_SIZE - PT_SIZE +2: + swi r11, r1, PT_MODE /* store the mode */ + lwi r11, r0, PER_CPU(R11_SAVE) /* reload r11 */ + /* save them on stack */ + swi r2, r1, PT_R2 + swi r3, r1, PT_R3 /* r3: _always_ in clobber list; see unistd.h */ + swi r4, r1, PT_R4 /* r4: _always_ in clobber list; see unistd.h */ + swi r5, r1, PT_R5 + swi r6, r1, PT_R6 + swi r7, r1, PT_R7 + swi r8, r1, PT_R8 + swi r9, r1, PT_R9 + swi r10, r1, PT_R10 + swi r11, r1, PT_R11 + /* r12: _always_ in clobber list; see unistd.h */ + swi r12, r1, PT_R12 + swi r13, r1, PT_R13 + /* r14: _always_ in clobber list; see unistd.h */ + swi r14, r1, PT_R14 + /* but we want to return to the next inst. */ + addik r14, r14, 0x4 + swi r14, r1, PT_PC /* increment by 4 and store in pc */ + swi r15, r1, PT_R15 + swi r16, r1, PT_R16 + swi r17, r1, PT_R17 + swi r18, r1, PT_R18 + swi r19, r1, PT_R19 + swi r20, r1, PT_R20 + swi r21, r1, PT_R21 + swi r22, r1, PT_R22 + swi r23, r1, PT_R23 + swi r24, r1, PT_R24 + swi r25, r1, PT_R25 + swi r26, r1, PT_R26 + swi r27, r1, PT_R27 + swi r28, r1, PT_R28 + swi r29, r1, PT_R29 + swi r30, r1, PT_R30 + swi r31, r1, PT_R31 + + disable_irq + nop /* make sure IE bit is in effect */ + clear_bip /* once IE is in effect it is safe to clear BIP */ + nop + + /* special purpose registers */ + mfs r11, rmsr + swi r11, r1, PT_MSR + mfs r11, rear + swi r11, r1, PT_EAR + mfs r11, resr + swi r11, r1, PT_ESR + mfs r11, rfsr + swi r11, r1, PT_FSR + /* reload original stack pointer and save it */ + lwi r11, r0, PER_CPU(ENTRY_SP) + swi r11, r1, PT_R1 + /* update mode indicator we are in kernel mode */ + addik r11, r0, 1 + swi r11, r0, PER_CPU(KM) + /* restore r31 */ + lwi r31, r0, PER_CPU(CURRENT_SAVE) + /* re-enable interrupts now we are in kernel mode */ + enable_irq + + /* See if the system call number is valid. */ + addi r11, r12, -__NR_syscalls + bgei r11, 1f /* return to user if not valid */ + /* Figure out which function to use for this system call. */ + /* Note Microblaze barrel shift is optional, so don't rely on it */ + add r12, r12, r12 /* convert num -> ptr */ + addik r30, r0, 1 /* restarts allowed */ + add r12, r12, r12 + lwi r12, r12, sys_call_table /* Get function pointer */ + addik r15, r0, ret_to_user-8 /* set return address */ + bra r12 /* Make the system call. */ + bri 0 /* won't reach here */ +1: + brid ret_to_user /* jump to syscall epilogue */ + addi r3, r0, -ENOSYS /* set errno in delay slot */ + +/* + * Debug traps are like a system call, but entered via brki r14, 0x60 + * All we need to do is send the SIGTRAP signal to current, ptrace and + * do_notify_resume will handle the rest + */ +ENTRY(_debug_exception) + swi r1, r0, PER_CPU(ENTRY_SP) /* save the current sp */ + lwi r1, r0, PER_CPU(CURRENT_SAVE) /* get the saved current */ + lwi r1, r1, TS_THREAD_INFO /* get the thread info */ + addik r1, r1, THREAD_SIZE - PT_SIZE /* get the kernel stack */ + swi r11, r0, PER_CPU(R11_SAVE) /* temporarily save r11 */ + lwi r11, r0, PER_CPU(KM) /* load mode indicator */ +//save_context: + swi r11, r1, PT_MODE /* store the mode */ + lwi r11, r0, PER_CPU(R11_SAVE) /* reload r11 */ + /* save them on stack */ + swi r2, r1, PT_R2 + swi r3, r1, PT_R3 /* r3: _always_ in clobber list; see unistd.h */ + swi r4, r1, PT_R4 /* r4: _always_ in clobber list; see unistd.h */ + swi r5, r1, PT_R5 + swi r6, r1, PT_R6 + swi r7, r1, PT_R7 + swi r8, r1, PT_R8 + swi r9, r1, PT_R9 + swi r10, r1, PT_R10 + swi r11, r1, PT_R11 + /* r12: _always_ in clobber list; see unistd.h */ + swi r12, r1, PT_R12 + swi r13, r1, PT_R13 + /* r14: _always_ in clobber list; see unistd.h */ + swi r14, r1, PT_R14 + swi r14, r1, PT_PC /* Will return to interrupted instruction */ + swi r15, r1, PT_R15 + swi r16, r1, PT_R16 + swi r17, r1, PT_R17 + swi r18, r1, PT_R18 + swi r19, r1, PT_R19 + swi r20, r1, PT_R20 + swi r21, r1, PT_R21 + swi r22, r1, PT_R22 + swi r23, r1, PT_R23 + swi r24, r1, PT_R24 + swi r25, r1, PT_R25 + swi r26, r1, PT_R26 + swi r27, r1, PT_R27 + swi r28, r1, PT_R28 + swi r29, r1, PT_R29 + swi r30, r1, PT_R30 + swi r31, r1, PT_R31 + + disable_irq + nop /* make sure IE bit is in effect */ + clear_bip /* once IE is in effect it is safe to clear BIP */ + nop + + /* special purpose registers */ + mfs r11, rmsr + swi r11, r1, PT_MSR + mfs r11, rear + swi r11, r1, PT_EAR + mfs r11, resr + swi r11, r1, PT_ESR + mfs r11, rfsr + swi r11, r1, PT_FSR + /* reload original stack pointer and save it */ + lwi r11, r0, PER_CPU(ENTRY_SP) + swi r11, r1, PT_R1 + /* update mode indicator we are in kernel mode */ + addik r11, r0, 1 + swi r11, r0, PER_CPU(KM) + /* restore r31 */ + lwi r31, r0, PER_CPU(CURRENT_SAVE) + /* re-enable interrupts now we are in kernel mode */ + enable_irq + + addi r5, r0, SIGTRAP /* sending the trap signal */ + add r6, r0, r31 /* to current */ + bralid r15, send_sig + add r7, r0, r0 /* 3rd param zero */ + + addik r30, r0, 1 /* restarts allowed ??? */ + /* Restore r3/r4 to work around how ret_to_user works */ + lwi r3, r1, PT_R3 + lwi r4, r1, PT_R4 + bri ret_to_user + +ENTRY(_break) + bri 0 + +/* struct task_struct *_switch_to(struct thread_info *prev, + struct thread_info *next); */ +ENTRY(_switch_to) + /* prepare return value */ + addk r3, r0, r31 + + /* save registers in cpu_context */ + /* use r11 and r12, volatile registers, as temp register */ + addik r11, r5, TI_CPU_CONTEXT + swi r1, r11, CC_R1 + swi r2, r11, CC_R2 + /* skip volatile registers. + * they are saved on stack when we jumped to _switch_to() */ + /* dedicated registers */ + swi r13, r11, CC_R13 + swi r14, r11, CC_R14 + swi r15, r11, CC_R15 + swi r16, r11, CC_R16 + swi r17, r11, CC_R17 + swi r18, r11, CC_R18 + /* save non-volatile registers */ + swi r19, r11, CC_R19 + swi r20, r11, CC_R20 + swi r21, r11, CC_R21 + swi r22, r11, CC_R22 + swi r23, r11, CC_R23 + swi r24, r11, CC_R24 + swi r25, r11, CC_R25 + swi r26, r11, CC_R26 + swi r27, r11, CC_R27 + swi r28, r11, CC_R28 + swi r29, r11, CC_R29 + swi r30, r11, CC_R30 + /* special purpose registers */ + mfs r12, rmsr + swi r12, r11, CC_MSR + mfs r12, rear + swi r12, r11, CC_EAR + mfs r12, resr + swi r12, r11, CC_ESR + mfs r12, rfsr + swi r12, r11, CC_FSR + + /* update r31, the current */ + lwi r31, r6, TI_TASK + swi r31, r0, PER_CPU(CURRENT_SAVE) + + /* get new process' cpu context and restore */ + addik r11, r6, TI_CPU_CONTEXT + + /* special purpose registers */ + lwi r12, r11, CC_FSR + mts rfsr, r12 + lwi r12, r11, CC_ESR + mts resr, r12 + lwi r12, r11, CC_EAR + mts rear, r12 + lwi r12, r11, CC_MSR + mts rmsr, r12 + /* non-volatile registers */ + lwi r30, r11, CC_R30 + lwi r29, r11, CC_R29 + lwi r28, r11, CC_R28 + lwi r27, r11, CC_R27 + lwi r26, r11, CC_R26 + lwi r25, r11, CC_R25 + lwi r24, r11, CC_R24 + lwi r23, r11, CC_R23 + lwi r22, r11, CC_R22 + lwi r21, r11, CC_R21 + lwi r20, r11, CC_R20 + lwi r19, r11, CC_R19 + /* dedicated registers */ + lwi r18, r11, CC_R18 + lwi r17, r11, CC_R17 + lwi r16, r11, CC_R16 + lwi r15, r11, CC_R15 + lwi r14, r11, CC_R14 + lwi r13, r11, CC_R13 + /* skip volatile registers */ + lwi r2, r11, CC_R2 + lwi r1, r11, CC_R1 + + rtsd r15, 8 + nop + +ENTRY(ret_from_fork) + addk r5, r0, r3 + brlid r15, schedule_tail + nop + swi r31, r1, PT_R31 /* save r31 in user context. */ + /* will soon be restored to r31 in ret_to_user */ + addk r3, r0, r0 + brid ret_to_user + nop + +ENTRY(ret_from_kernel_thread) + brlid r15, schedule_tail + addk r5, r0, r3 + brald r15, r20 + addk r5, r0, r19 + brid ret_to_user + addk r3, r0, r0 + +work_pending: + lwi r11, r1, PT_MODE + bneid r11, 2f +3: + enable_irq + andi r11, r19, _TIF_NEED_RESCHED + beqi r11, 1f + bralid r15, schedule + nop + bri 4f +1: andi r11, r19, _TIF_SIGPENDING | _TIF_NOTIFY_RESUME + beqi r11, no_work_pending + addk r5, r30, r0 + bralid r15, do_notify_resume + addik r6, r0, 1 + addk r30, r0, r0 /* no restarts from now on */ +4: + disable_irq + lwi r6, r31, TS_THREAD_INFO /* get thread info */ + lwi r19, r6, TI_FLAGS /* get flags in thread info */ + bri 3b + +ENTRY(ret_to_user) + disable_irq + + swi r4, r1, PT_R4 /* return val */ + swi r3, r1, PT_R3 /* return val */ + + lwi r6, r31, TS_THREAD_INFO /* get thread info */ + lwi r19, r6, TI_FLAGS /* get flags in thread info */ + bnei r19, work_pending /* do an extra work if any bits are set */ +no_work_pending: + disable_irq + +2: + /* save r31 */ + swi r31, r0, PER_CPU(CURRENT_SAVE) + /* save mode indicator */ + lwi r18, r1, PT_MODE + swi r18, r0, PER_CPU(KM) +//restore_context: + /* special purpose registers */ + lwi r18, r1, PT_FSR + mts rfsr, r18 + lwi r18, r1, PT_ESR + mts resr, r18 + lwi r18, r1, PT_EAR + mts rear, r18 + lwi r18, r1, PT_MSR + mts rmsr, r18 + + lwi r31, r1, PT_R31 + lwi r30, r1, PT_R30 + lwi r29, r1, PT_R29 + lwi r28, r1, PT_R28 + lwi r27, r1, PT_R27 + lwi r26, r1, PT_R26 + lwi r25, r1, PT_R25 + lwi r24, r1, PT_R24 + lwi r23, r1, PT_R23 + lwi r22, r1, PT_R22 + lwi r21, r1, PT_R21 + lwi r20, r1, PT_R20 + lwi r19, r1, PT_R19 + lwi r18, r1, PT_R18 + lwi r17, r1, PT_R17 + lwi r16, r1, PT_R16 + lwi r15, r1, PT_R15 + lwi r14, r1, PT_PC + lwi r13, r1, PT_R13 + lwi r12, r1, PT_R12 + lwi r11, r1, PT_R11 + lwi r10, r1, PT_R10 + lwi r9, r1, PT_R9 + lwi r8, r1, PT_R8 + lwi r7, r1, PT_R7 + lwi r6, r1, PT_R6 + lwi r5, r1, PT_R5 + lwi r4, r1, PT_R4 /* return val */ + lwi r3, r1, PT_R3 /* return val */ + lwi r2, r1, PT_R2 + lwi r1, r1, PT_R1 + + rtid r14, 0 + nop + +sys_rt_sigreturn_wrapper: + addk r30, r0, r0 /* no restarts for this one */ + brid sys_rt_sigreturn + addk r5, r1, r0 + + /* Interrupt vector table */ + .section .init.ivt, "ax" + .org 0x0 + brai _reset + brai _user_exception + brai _interrupt + brai _break + brai _hw_exception_handler + .org 0x60 + brai _debug_exception + +.section .rodata,"a" +#include "syscall_table.S" + +syscall_table_size=(.-sys_call_table) + +type_SYSCALL: + .ascii "SYSCALL\0" +type_IRQ: + .ascii "IRQ\0" +type_IRQ_PREEMPT: + .ascii "IRQ (PREEMPTED)\0" +type_SYSCALL_PREEMPT: + .ascii " SYSCALL (PREEMPTED)\0" + + /* + * Trap decoding for stack unwinder + * Tuples are (start addr, end addr, string) + * If return address lies on [start addr, end addr], + * unwinder displays 'string' + */ + + .align 4 +.global microblaze_trap_handlers +microblaze_trap_handlers: + /* Exact matches come first */ + .word ret_to_user ; .word ret_to_user ; .word type_SYSCALL + .word ret_from_intr; .word ret_from_intr ; .word type_IRQ + /* Fuzzy matches go here */ + .word ret_from_intr; .word no_intr_resched; .word type_IRQ_PREEMPT + .word work_pending ; .word no_work_pending; .word type_SYSCALL_PREEMPT + /* End of table */ + .word 0 ; .word 0 ; .word 0 |