From de39840646a223ae13a346048c280b7c871bf56e Mon Sep 17 00:00:00 2001 From: Yoshinori Sato Date: Sun, 5 Nov 2006 16:15:19 +0900 Subject: [PATCH] sh: Exception vector rework and SH-2/SH-2A support. This splits out common bits from the existing exception handler for use between SH-2/SH-2A and SH-3/4, and adds support for the SH-2/2A exceptions. Signed-off-by: Yoshinori Sato Signed-off-by: Paul Mundt --- arch/sh/kernel/cpu/sh2/entry.S | 325 +++++++++++++++++++++++ arch/sh/kernel/cpu/sh2/ex.S | 46 ++++ arch/sh/kernel/cpu/sh3/Makefile | 2 +- arch/sh/kernel/{ => cpu/sh3}/entry.S | 339 +----------------------- arch/sh/kernel/cpu/sh4/Makefile | 3 +- arch/sh/kernel/entry-common.S | 372 +++++++++++++++++++++++++++ arch/sh/kernel/head.S | 12 +- 7 files changed, 767 insertions(+), 332 deletions(-) create mode 100644 arch/sh/kernel/cpu/sh2/entry.S create mode 100644 arch/sh/kernel/cpu/sh2/ex.S rename arch/sh/kernel/{ => cpu/sh3}/entry.S (59%) create mode 100644 arch/sh/kernel/entry-common.S diff --git a/arch/sh/kernel/cpu/sh2/entry.S b/arch/sh/kernel/cpu/sh2/entry.S new file mode 100644 index 000000000000..298d9191909d --- /dev/null +++ b/arch/sh/kernel/cpu/sh2/entry.S @@ -0,0 +1,325 @@ +/* + * arch/sh/kernel/cpu/sh2/entry.S + * + * The SH-2 exception entry + * + * Copyright (C) 2005,2006 Yoshinori Sato + * Copyright (C) 2005 AXE,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 +#include +#include +#include +#include +#include +#include + +/* 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 + +ENTRY(exception_handler) + ! already saved r0/r1 + mov.l r2,@-sp + mov.l r3,@-sp + mov r0,r1 + cli + mov.l $cpu_mode,r2 + mov.l @r2,r0 + mov.l @(5*4,r15),r3 ! previous SR + shll2 r3 ! set "S" flag + rotl r0 ! T <- "S" flag + rotl r0 ! "S" flag is LSB + rotcr r3 ! T -> r3:b30 + shlr r3 + shlr r0 + bt/s 1f + mov.l r3,@(5*4,r15) ! copy cpu mode to SR + ! switch to kernel mode + mov #1,r0 + rotr r0 + rotr r0 + mov.l r0,@r2 ! enter kernel mode + mov.l $current_thread_info,r2 + mov.l @r2,r2 + mov #0x20,r0 + shll8 r0 + add r2,r0 + mov r15,r2 ! r2 = user stack top + mov r0,r15 ! switch kernel stack + add #-4,r15 ! dummy + 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 @(5*4,r2),r1 + mov.l r1,@-r15 ! original SR + sts.l pr,@-r15 + mov.l r0,@-r15 ! original PC + mov r2,r3 + add #(4+2)*4,r3 ! rewind r0 - r3 + exception frame + mov.l r3,@-r15 ! original SP + mov.l r14,@-r15 + mov.l r13,@-r15 + mov.l r12,@-r15 + mov.l r11,@-r15 + mov.l r10,@-r15 + mov.l r9,@-r15 + mov.l r8,@-r15 + mov.l r7,@-r15 + mov.l r6,@-r15 + mov.l r5,@-r15 + mov.l r4,@-r15 + mov r2,r8 ! copy user -> kernel stack + mov.l @r8+,r3 + mov.l r3,@-r15 + mov.l @r8+,r2 + mov.l r2,@-r15 + mov.l @r8+,r1 + mov.l r1,@-r15 + mov.l @r8+,r0 + bra 2f + mov.l r0,@-r15 +1: + ! in kernel exception + mov #(22-4-4-1)*4+4,r0 + mov r15,r2 + sub r0,r15 + mov.l @r2+,r0 ! old R3 + mov.l r0,@-r15 + mov.l @r2+,r0 ! old R2 + mov.l r0,@-r15 + mov.l @r2+,r0 ! old R1 + mov.l r0,@-r15 + mov.l @r2+,r0 ! old R0 + mov.l r0,@-r15 + mov.l @r2+,r3 ! old PC + mov.l @r2+,r0 ! old SR + add #-4,r2 ! exception frame stub (sr) + mov.l r1,@-r2 ! TRA + sts.l macl, @-r2 + sts.l mach, @-r2 + stc.l gbr, @-r2 + mov.l r0,@-r2 ! save old SR + sts.l pr,@-r2 + mov.l r3,@-r2 ! save old PC + mov r2,r0 + add #8*4,r0 + mov.l r0,@-r2 ! save old SP + mov.l r14,@-r2 + mov.l r13,@-r2 + mov.l r12,@-r2 + mov.l r11,@-r2 + mov.l r10,@-r2 + mov.l r9,@-r2 + mov.l r8,@-r2 + mov.l r7,@-r2 + mov.l r6,@-r2 + mov.l r5,@-r2 + mov.l r4,@-r2 + mov.l @(OFF_R0,r15),r0 + mov.l @(OFF_R1,r15),r1 + mov.l @(OFF_R2,r15),r2 + mov.l @(OFF_R3,r15),r3 +2: + mov #OFF_TRA,r8 + add r15,r8 + mov.l @r8,r9 + mov #64,r8 + cmp/hs r8,r9 + bt interrupt_entry ! vec >= 64 is interrupt + mov #32,r8 + cmp/hs r8,r9 + bt trap_entry ! 64 > vec >= 32 is trap + mov.l 4f,r8 + mov r9,r4 + shll2 r9 + add r9,r8 + mov.l @r8,r8 + mov #0,r9 + cmp/eq r9,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.l 6f,r9 + mov.l 7f,r8 + 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 do_exception_error + +trap_entry: + add #-0x10,r9 + shll2 r9 ! TRA + mov #OFF_TRA,r8 + add r15,r8 + mov.l r9,@r8 + mov r9,r8 + sti + bra system_call + nop + + .align 2 +1: .long syscall_exit +2: .long break_point_trap_software +3: .long NR_syscalls +4: .long sys_call_table + +#if defined(CONFIG_SH_STANDARD_BIOS) + /* Unwind the stack and jmp to the debug entry */ +debug_kernel_fw: + 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 #OFF_SR,r2 + mov.l @(r0,r2),r3 + mov.l r3,@-r1 + mov #OFF_SP,r2 + mov.l @(r0,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,@r0 + mov.l r1,@(8,r0) + mov.l @r15+, r0 + mov.l @r15+, r1 + mov.l @r15+, r2 + mov.l @r15+, r3 + mov.l @r15+, r4 + mov.l @r15+, r5 + mov.l @r15+, r6 + mov.l @r15+, r7 + mov.l @r15+, r8 + mov.l @r15+, r9 + mov.l @r15+, r10 + mov.l @r15+, r11 + mov.l @r15+, r12 + mov.l @r15+, r13 + mov.l @r15+, r14 + add #8,r15 + lds.l @r15+, pr + rte + mov.l @r15+,r15 + .align 2 +1: .long gdb_vbr_vector +#endif /* CONFIG_SH_STANDARD_BIOS */ + +ENTRY(address_error_handler) + mov r15,r4 ! regs + add #4,r4 + mov #OFF_PC,r0 + mov.l @(r0,r15),r6 ! pc + mov.l 1f,r0 + jmp @r0 + mov #0,r5 ! writeaccess is unknown + .align 2 + +1: .long do_address_error + +restore_all: + cli + mov r15,r0 + mov.l $cpu_mode,r2 + mov #OFF_SR,r3 + mov.l @(r0,r3),r1 + mov.l r1,@r2 + shll2 r1 ! clear MD bit + shlr2 r1 + 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 #OFF_PC,r3 + mov.l @(r0,r3),r1 + mov.l r1,@r2 ! set pc + add #4*16+4,r0 + lds.l @r0+,pr + add #4,r0 ! skip sr + ldc.l @r0+,gbr + lds.l @r0+,mach + lds.l @r0+,macl + get_current_thread_info r0, r1 + mov.l $current_thread_info,r1 + mov.l r0,@r1 + mov.l @r15+,r0 + mov.l @r15+,r1 + mov.l @r15+,r2 + mov.l @r15+,r3 + mov.l @r15+,r4 + mov.l @r15+,r5 + mov.l @r15+,r6 + mov.l @r15+,r7 + mov.l @r15+,r8 + mov.l @r15+,r9 + mov.l @r15+,r10 + mov.l @r15+,r11 + mov.l @r15+,r12 + mov.l @r15+,r13 + mov.l @r15+,r14 + mov.l @r15,r15 + rte + nop +2: + mov.l 1f,r8 + mov.l 2f,r9 + jmp @r9 + lds r8,pr + + .align 2 +$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 diff --git a/arch/sh/kernel/cpu/sh2/ex.S b/arch/sh/kernel/cpu/sh2/ex.S new file mode 100644 index 000000000000..6d285af7846c --- /dev/null +++ b/arch/sh/kernel/cpu/sh2/ex.S @@ -0,0 +1,46 @@ +/* + * arch/sh/kernel/cpu/sh2/ex.S + * + * The SH-2 exception vector table + * + * Copyright (C) 2005 Yoshinori Sato + * + * 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 + +! +! convert Exception Vector to Exception Number +! +exception_entry: +no = 0 + .rept 256 + mov.l r0,@-sp + mov #no,r0 + bra exception_trampoline + and #0xff,r0 +no = no + 1 + .endr +exception_trampoline: + mov.l r1,@-sp + mov.l $exception_handler,r1 + jmp @r1 + + .align 2 +$exception_entry: + .long exception_entry +$exception_handler: + .long exception_handler +! +! Exception Vector Base +! + .align 2 +ENTRY(vbr_base) +vector = 0 + .rept 256 + .long exception_entry + vector * 8 +vector = vector + 1 + .endr diff --git a/arch/sh/kernel/cpu/sh3/Makefile b/arch/sh/kernel/cpu/sh3/Makefile index 58d3815695ff..83905e4e4387 100644 --- a/arch/sh/kernel/cpu/sh3/Makefile +++ b/arch/sh/kernel/cpu/sh3/Makefile @@ -2,7 +2,7 @@ # Makefile for the Linux/SuperH SH-3 backends. # -obj-y := ex.o probe.o +obj-y := ex.o probe.o entry.o # CPU subtype setup obj-$(CONFIG_CPU_SUBTYPE_SH7705) += setup-sh7705.o diff --git a/arch/sh/kernel/entry.S b/arch/sh/kernel/cpu/sh3/entry.S similarity index 59% rename from arch/sh/kernel/entry.S rename to arch/sh/kernel/cpu/sh3/entry.S index 39aaefb2d83f..8bcd63f9f351 100644 --- a/arch/sh/kernel/entry.S +++ b/arch/sh/kernel/cpu/sh3/entry.S @@ -1,5 +1,5 @@ /* - * linux/arch/sh/entry.S + * arch/sh/kernel/entry.S * * Copyright (C) 1999, 2000, 2002 Niibe Yutaka * Copyright (C) 2003 - 2006 Paul Mundt @@ -7,7 +7,6 @@ * 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 #include @@ -81,6 +80,8 @@ OFF_TRA = (16*4+6*4) #define k_g_imask r6_bank /* r6_bank1 */ #define current r7 /* r7_bank1 */ +#include + /* * Kernel mode register usage: * k0 scratch @@ -107,26 +108,6 @@ OFF_TRA = (16*4+6*4) ! this first version depends *much* on C implementation. ! -#define CLI() \ - stc sr, r0; \ - or #0xf0, r0; \ - ldc r0, sr - -#define STI() \ - mov.l __INV_IMASK, r11; \ - stc sr, r10; \ - and r11, r10; \ - stc k_g_imask, r11; \ - or r11, r10; \ - ldc r10, sr - -#if defined(CONFIG_PREEMPT) -# define preempt_stop() CLI() -#else -# define preempt_stop() -# define resume_kernel restore_all -#endif - #if defined(CONFIG_MMU) .align 2 ENTRY(tlb_miss_load) @@ -168,7 +149,7 @@ call_dpf: lds r10, pr rts nop -0: STI() +0: sti mov.l 3f, r0 mov r9, r6 mov r8, r5 @@ -203,32 +184,6 @@ call_dae: 2: .long do_address_error #endif /* CONFIG_MMU */ -#if defined(CONFIG_SH_STANDARD_BIOS) || defined(CONFIG_SH_KGDB) -! Handle kernel debug if either kgdb (SW) or gdb-stub (FW) is present. -! If both are configured, handle the debug traps (breakpoints) in SW, -! but still allow BIOS traps to FW. - - .align 2 -debug_kernel: -#if defined(CONFIG_SH_STANDARD_BIOS) && defined(CONFIG_SH_KGDB) - /* Force BIOS call to FW (debug_trap put TRA in r8) */ - mov r8,r0 - shlr2 r0 - cmp/eq #0x3f,r0 - bt debug_kernel_fw -#endif /* CONFIG_SH_STANDARD_BIOS && CONFIG_SH_KGDB */ - -debug_enter: -#if defined(CONFIG_SH_KGDB) - /* Jump to kgdb, pass stacked regs as arg */ -debug_kernel_sw: - mov.l 3f, r0 - jmp @r0 - mov r15, r4 - .align 2 -3: .long kgdb_handle_exception -#endif /* CONFIG_SH_KGDB */ - #if defined(CONFIG_SH_STANDARD_BIOS) /* Unwind the stack and jmp to the debug entry */ debug_kernel_fw: @@ -269,276 +224,6 @@ debug_kernel_fw: 2: .long gdb_vbr_vector #endif /* CONFIG_SH_STANDARD_BIOS */ -#endif /* CONFIG_SH_STANDARD_BIOS || CONFIG_SH_KGDB */ - - - .align 2 -debug_trap: -#if defined(CONFIG_SH_STANDARD_BIOS) || defined(CONFIG_SH_KGDB) - mov #OFF_SR, r0 - mov.l @(r0,r15), r0 ! get status register - shll r0 - shll r0 ! kernel space? - bt/s debug_kernel -#endif - mov.l @r15, r0 ! Restore R0 value - mov.l 1f, r8 - jmp @r8 - nop - - .align 2 -ENTRY(exception_error) - ! - STI() - mov.l 2f, r0 - jmp @r0 - nop - -! - .align 2 -1: .long break_point_trap_software -2: .long do_exception_error - - .align 2 -ret_from_exception: - preempt_stop() -ENTRY(ret_from_irq) - ! - mov #OFF_SR, r0 - mov.l @(r0,r15), r0 ! get status register - shll r0 - shll r0 ! kernel space? - bt/s resume_kernel ! Yes, it's from kernel, go back soon - GET_THREAD_INFO(r8) - -#ifdef CONFIG_PREEMPT - bra resume_userspace - nop -ENTRY(resume_kernel) - mov.l @(TI_PRE_COUNT,r8), r0 ! current_thread_info->preempt_count - tst r0, r0 - bf noresched -need_resched: - mov.l @(TI_FLAGS,r8), r0 ! current_thread_info->flags - tst #_TIF_NEED_RESCHED, r0 ! need_resched set? - bt noresched - - mov #OFF_SR, r0 - mov.l @(r0,r15), r0 ! get status register - and #0xf0, r0 ! interrupts off (exception path)? - cmp/eq #0xf0, r0 - bt noresched - - mov.l 1f, r0 - mov.l r0, @(TI_PRE_COUNT,r8) - - STI() - mov.l 2f, r0 - jsr @r0 - nop - mov #0, r0 - mov.l r0, @(TI_PRE_COUNT,r8) - CLI() - - bra need_resched - nop -noresched: - bra restore_all - nop - - .align 2 -1: .long PREEMPT_ACTIVE -2: .long schedule -#endif - -ENTRY(resume_userspace) - ! r8: current_thread_info - CLI() - mov.l @(TI_FLAGS,r8), r0 ! current_thread_info->flags - tst #_TIF_WORK_MASK, r0 - bt/s restore_all - tst #_TIF_NEED_RESCHED, r0 - - .align 2 -work_pending: - ! r0: current_thread_info->flags - ! r8: current_thread_info - ! t: result of "tst #_TIF_NEED_RESCHED, r0" - bf/s work_resched - tst #(_TIF_SIGPENDING | _TIF_RESTORE_SIGMASK), r0 -work_notifysig: - bt/s restore_all - mov r15, r4 - mov r12, r5 ! set arg1(save_r0) - mov r0, r6 - mov.l 2f, r1 - mova restore_all, r0 - jmp @r1 - lds r0, pr -work_resched: -#ifndef CONFIG_PREEMPT - ! gUSA handling - mov.l @(OFF_SP,r15), r0 ! get user space stack pointer - mov r0, r1 - shll r0 - bf/s 1f - shll r0 - bf/s 1f - mov #OFF_PC, r0 - ! SP >= 0xc0000000 : gUSA mark - mov.l @(r0,r15), r2 ! get user space PC (program counter) - mov.l @(OFF_R0,r15), r3 ! end point - cmp/hs r3, r2 ! r2 >= r3? - bt 1f - add r3, r1 ! rewind point #2 - mov.l r1, @(r0,r15) ! reset PC to rewind point #2 - ! -1: -#endif - mov.l 1f, r1 - jsr @r1 ! schedule - nop - CLI() - ! - mov.l @(TI_FLAGS,r8), r0 ! current_thread_info->flags - tst #_TIF_WORK_MASK, r0 - bt restore_all - bra work_pending - tst #_TIF_NEED_RESCHED, r0 - - .align 2 -1: .long schedule -2: .long do_notify_resume - - .align 2 -syscall_exit_work: - ! r0: current_thread_info->flags - ! r8: current_thread_info - tst #_TIF_SYSCALL_TRACE, r0 - bt/s work_pending - tst #_TIF_NEED_RESCHED, r0 - STI() - ! XXX setup arguments... - mov.l 4f, r0 ! do_syscall_trace - jsr @r0 - nop - bra resume_userspace - nop - - .align 2 -syscall_trace_entry: - ! Yes it is traced. - ! XXX setup arguments... - mov.l 4f, r11 ! Call do_syscall_trace which notifies - jsr @r11 ! superior (will chomp R[0-7]) - nop - ! Reload R0-R4 from kernel stack, where the - ! parent may have modified them using - ! ptrace(POKEUSR). (Note that R0-R2 are - ! used by the system call handler directly - ! from the kernel stack anyway, so don't need - ! to be reloaded here.) This allows the parent - ! to rewrite system calls and args on the fly. - mov.l @(OFF_R4,r15), r4 ! arg0 - mov.l @(OFF_R5,r15), r5 - mov.l @(OFF_R6,r15), r6 - mov.l @(OFF_R7,r15), r7 ! arg3 - mov.l @(OFF_R3,r15), r3 ! syscall_nr - ! Arrange for do_syscall_trace to be called - ! again as the system call returns. - mov.l 2f, r10 ! Number of syscalls - cmp/hs r10, r3 - bf syscall_call - mov #-ENOSYS, r0 - bra syscall_exit - mov.l r0, @(OFF_R0,r15) ! Return value - -/* - * Syscall interface: - * - * Syscall #: R3 - * Arguments #0 to #3: R4--R7 - * Arguments #4 to #6: R0, R1, R2 - * TRA: (number of arguments + 0x10) x 4 - * - * This code also handles delegating other traps to the BIOS/gdb stub - * according to: - * - * Trap number - * (TRA>>2) Purpose - * -------- ------- - * 0x0-0xf old syscall ABI - * 0x10-0x1f new syscall ABI - * 0x20-0xff delegated through debug_trap to BIOS/gdb stub. - * - * Note: When we're first called, the TRA value must be shifted - * right 2 bits in order to get the value that was used as the "trapa" - * argument. - */ - - .align 2 - .globl ret_from_fork -ret_from_fork: - mov.l 1f, r8 - jsr @r8 - mov r0, r4 - bra syscall_exit - nop - .align 2 -1: .long schedule_tail - ! -ENTRY(system_call) - mov.l 1f, r9 - mov.l @r9, r8 ! Read from TRA (Trap Address) Register - ! - ! Is the trap argument >= 0x20? (TRA will be >= 0x80) - mov #0x7f, r9 - cmp/hi r9, r8 - bt/s 0f - mov #OFF_TRA, r9 - add r15, r9 - ! - mov.l r8, @r9 ! set TRA value to tra - STI() - ! Call the system call handler through the table. - ! First check for bad syscall number - mov r3, r9 - mov.l 2f, r8 ! Number of syscalls - cmp/hs r8, r9 - bf/s good_system_call - GET_THREAD_INFO(r8) -syscall_badsys: ! Bad syscall number - mov #-ENOSYS, r0 - bra resume_userspace - mov.l r0, @(OFF_R0,r15) ! Return value - ! -0: - bra debug_trap - nop - ! -good_system_call: ! Good syscall number - mov.l @(TI_FLAGS,r8), r8 - mov #_TIF_SYSCALL_TRACE, r10 - tst r10, r8 - bf syscall_trace_entry - ! -syscall_call: - shll2 r9 ! x4 - mov.l 3f, r8 ! Load the address of sys_call_table - add r8, r9 - mov.l @r9, r8 - jsr @r8 ! jump to specific syscall handler - nop - mov.l @(OFF_R0,r15), r12 ! save r0 - mov.l r0, @(OFF_R0,r15) ! save the return value - ! -syscall_exit: - CLI() - ! - GET_THREAD_INFO(r8) - mov.l @(TI_FLAGS,r8), r0 ! current_thread_info->flags - tst #_TIF_ALLWORK_MASK, r0 - bf syscall_exit_work restore_all: mov.l @r15+, r0 mov.l @r15+, r1 @@ -606,7 +291,9 @@ skip_restore: ! ! Calculate new SR value mov k3, k2 ! original SR value - mov.l 9f, k1 + mov #0xf0, k1 + extu.b k1, k1 + not k1, k1 and k1, k2 ! Mask orignal SR value ! mov k3, k0 ! Calculate IMASK-bits @@ -632,16 +319,12 @@ skip_restore: nop .align 2 -1: .long TRA -2: .long NR_syscalls -3: .long sys_call_table -4: .long do_syscall_trace 5: .long 0x00001000 ! DSP 7: .long 0x30000000 -9: -__INV_IMASK: - .long 0xffffff0f ! ~(IMASK) +! common exception handler +#include "../../entry.S" + ! Exception Vector Base ! ! Should be aligned page boundary. @@ -761,7 +444,7 @@ skip_save: ! Save the user registers on the stack. mov.l k2, @-r15 ! EXPEVT - mov #-1, k4 + mov #-1, k4 mov.l k4, @-r15 ! set TRA (default: -1) ! sts.l macl, @-r15 diff --git a/arch/sh/kernel/cpu/sh4/Makefile b/arch/sh/kernel/cpu/sh4/Makefile index 8dbf3895ece7..6e415baf04b4 100644 --- a/arch/sh/kernel/cpu/sh4/Makefile +++ b/arch/sh/kernel/cpu/sh4/Makefile @@ -2,7 +2,8 @@ # Makefile for the Linux/SuperH SH-4 backends. # -obj-y := ex.o probe.o +obj-y := ex.o probe.o common.o +common-y += $(addprefix ../sh3/, entry.o) obj-$(CONFIG_SH_FPU) += fpu.o obj-$(CONFIG_SH_STORE_QUEUES) += sq.o diff --git a/arch/sh/kernel/entry-common.S b/arch/sh/kernel/entry-common.S new file mode 100644 index 000000000000..5bc7fa91d095 --- /dev/null +++ b/arch/sh/kernel/entry-common.S @@ -0,0 +1,372 @@ +/* $Id: entry.S,v 1.37 2004/06/11 13:02:46 doyu Exp $ + * + * linux/arch/sh/entry.S + * + * Copyright (C) 1999, 2000, 2002 Niibe Yutaka + * Copyright (C) 2003 Paul Mundt + * + * 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. + * + */ + +! NOTE: +! GNU as (as of 2.9.1) changes bf/s into bt/s and bra, when the address +! to be jumped is too far, but it causes illegal slot exception. + +/* + * entry.S contains the system-call and fault low-level handling routines. + * This also contains the timer-interrupt handler, as well as all interrupts + * and faults that can result in a task-switch. + * + * NOTE: This code handles signal-recognition, which happens every time + * after a timer-interrupt and after each system call. + * + * NOTE: This code uses a convention that instructions in the delay slot + * of a transfer-control instruction are indented by an extra space, thus: + * + * jmp @k0 ! control-transfer instruction + * ldc k1, ssr ! delay slot + * + * Stack layout in 'ret_from_syscall': + * ptrace needs to have all regs on the stack. + * if the order here is changed, it needs to be + * updated in ptrace.c and ptrace.h + * + * r0 + * ... + * r15 = stack pointer + * spc + * pr + * ssr + * gbr + * mach + * macl + * syscall # + * + */ + +#if defined(CONFIG_PREEMPT) +# define preempt_stop() cli +#else +# define preempt_stop() +# define resume_kernel __restore_all +#endif + +#if defined(CONFIG_SH_STANDARD_BIOS) || defined(CONFIG_SH_KGDB) +! Handle kernel debug if either kgdb (SW) or gdb-stub (FW) is present. +! If both are configured, handle the debug traps (breakpoints) in SW, +! but still allow BIOS traps to FW. + + .align 2 +debug_kernel: +#if defined(CONFIG_SH_STANDARD_BIOS) && defined(CONFIG_SH_KGDB) + /* Force BIOS call to FW (debug_trap put TRA in r8) */ + mov r8,r0 + shlr2 r0 + cmp/eq #0x3f,r0 + bt debug_kernel_fw +#endif /* CONFIG_SH_STANDARD_BIOS && CONFIG_SH_KGDB */ + +debug_enter: +#if defined(CONFIG_SH_KGDB) + /* Jump to kgdb, pass stacked regs as arg */ +debug_kernel_sw: + mov.l 3f, r0 + jmp @r0 + mov r15, r4 + .align 2 +3: .long kgdb_handle_exception +#endif /* CONFIG_SH_KGDB */ + +#endif /* CONFIG_SH_STANDARD_BIOS || CONFIG_SH_KGDB */ + + + .align 2 +debug_trap: +#if defined(CONFIG_SH_STANDARD_BIOS) || defined(CONFIG_SH_KGDB) + mov #OFF_SR, r0 + mov.l @(r0,r15), r0 ! get status register + shll r0 + shll r0 ! kernel space? + bt/s debug_kernel +#endif + mov.l @r15, r0 ! Restore R0 value + mov.l 1f, r8 + jmp @r8 + nop + + .align 2 +ENTRY(exception_error) + ! + sti + mov.l 2f, r0 + jmp @r0 + nop + +! + .align 2 +1: .long break_point_trap_software +2: .long do_exception_error + + .align 2 +ret_from_exception: + preempt_stop() +ENTRY(ret_from_irq) + ! + mov #OFF_SR, r0 + mov.l @(r0,r15), r0 ! get status register + shll r0 + shll r0 ! kernel space? + get_current_thread_info r8, r0 + bt resume_kernel ! Yes, it's from kernel, go back soon + +#ifdef CONFIG_PREEMPT + bra resume_userspace + nop +ENTRY(resume_kernel) + mov.l @(TI_PRE_COUNT,r8), r0 ! current_thread_info->preempt_count + tst r0, r0 + bf noresched +need_resched: + mov.l @(TI_FLAGS,r8), r0 ! current_thread_info->flags + tst #_TIF_NEED_RESCHED, r0 ! need_resched set? + bt noresched + + mov #OFF_SR, r0 + mov.l @(r0,r15), r0 ! get status register + and #0xf0, r0 ! interrupts off (exception path)? + cmp/eq #0xf0, r0 + bt noresched + + mov.l 1f, r0 + mov.l r0, @(TI_PRE_COUNT,r8) + + sti + mov.l 2f, r0 + jsr @r0 + nop + mov #0, r0 + mov.l r0, @(TI_PRE_COUNT,r8) + cli + + bra need_resched + nop +noresched: + bra __restore_all + nop + + .align 2 +1: .long PREEMPT_ACTIVE +2: .long schedule +#endif + +ENTRY(resume_userspace) + ! r8: current_thread_info + cli + mov.l @(TI_FLAGS,r8), r0 ! current_thread_info->flags + tst #_TIF_WORK_MASK, r0 + bt/s __restore_all + tst #_TIF_NEED_RESCHED, r0 + + .align 2 +work_pending: + ! r0: current_thread_info->flags + ! r8: current_thread_info + ! t: result of "tst #_TIF_NEED_RESCHED, r0" + bf/s work_resched + tst #(_TIF_SIGPENDING | _TIF_RESTORE_SIGMASK), r0 +work_notifysig: + bt/s __restore_all + mov r15, r4 + mov r12, r5 ! set arg1(save_r0) + mov r0, r6 + mov.l 2f, r1 + mov.l 3f, r0 + jmp @r1 + lds r0, pr +work_resched: +#ifndef CONFIG_PREEMPT + ! gUSA handling + mov.l @(OFF_SP,r15), r0 ! get user space stack pointer + mov r0, r1 + shll r0 + bf/s 1f + shll r0 + bf/s 1f + mov #OFF_PC, r0 + ! SP >= 0xc0000000 : gUSA mark + mov.l @(r0,r15), r2 ! get user space PC (program counter) + mov.l @(OFF_R0,r15), r3 ! end point + cmp/hs r3, r2 ! r2 >= r3? + bt 1f + add r3, r1 ! rewind point #2 + mov.l r1, @(r0,r15) ! reset PC to rewind point #2 + ! +1: +#endif + mov.l 1f, r1 + jsr @r1 ! schedule + nop + cli + ! + mov.l @(TI_FLAGS,r8), r0 ! current_thread_info->flags + tst #_TIF_WORK_MASK, r0 + bt __restore_all + bra work_pending + tst #_TIF_NEED_RESCHED, r0 + + .align 2 +1: .long schedule +2: .long do_notify_resume +3: .long restore_all + + .align 2 +syscall_exit_work: + ! r0: current_thread_info->flags + ! r8: current_thread_info + tst #_TIF_SYSCALL_TRACE, r0 + bt/s work_pending + tst #_TIF_NEED_RESCHED, r0 + sti + ! XXX setup arguments... + mov.l 4f, r0 ! do_syscall_trace + jsr @r0 + nop + bra resume_userspace + nop + + .align 2 +syscall_trace_entry: + ! Yes it is traced. + ! XXX setup arguments... + mov.l 4f, r11 ! Call do_syscall_trace which notifies + jsr @r11 ! superior (will chomp R[0-7]) + nop + ! Reload R0-R4 from kernel stack, where the + ! parent may have modified them using + ! ptrace(POKEUSR). (Note that R0-R2 are + ! used by the system call handler directly + ! from the kernel stack anyway, so don't need + ! to be reloaded here.) This allows the parent + ! to rewrite system calls and args on the fly. + mov.l @(OFF_R4,r15), r4 ! arg0 + mov.l @(OFF_R5,r15), r5 + mov.l @(OFF_R6,r15), r6 + mov.l @(OFF_R7,r15), r7 ! arg3 + mov.l @(OFF_R3,r15), r3 ! syscall_nr + ! Arrange for do_syscall_trace to be called + ! again as the system call returns. + mov.l 2f, r10 ! Number of syscalls + cmp/hs r10, r3 + bf syscall_call + mov #-ENOSYS, r0 + bra syscall_exit + mov.l r0, @(OFF_R0,r15) ! Return value + +__restore_all: + mov.l 1f,r0 + jmp @r0 + nop + + .align 2 +1: .long restore_all + +/* + * Syscall interface: + * + * Syscall #: R3 + * Arguments #0 to #3: R4--R7 + * Arguments #4 to #6: R0, R1, R2 + * TRA: (number of arguments + 0x10) x 4 + * + * This code also handles delegating other traps to the BIOS/gdb stub + * according to: + * + * Trap number + * (TRA>>2) Purpose + * -------- ------- + * 0x0-0xf old syscall ABI + * 0x10-0x1f new syscall ABI + * 0x20-0xff delegated through debug_trap to BIOS/gdb stub. + * + * Note: When we're first called, the TRA value must be shifted + * right 2 bits in order to get the value that was used as the "trapa" + * argument. + */ + + .align 2 + .globl ret_from_fork +ret_from_fork: + mov.l 1f, r8 + jsr @r8 + mov r0, r4 + bra syscall_exit + nop + .align 2 +1: .long schedule_tail + ! +ENTRY(system_call) +#if !defined(CONFIG_CPU_SH2) + mov.l 1f, r9 + mov.l @r9, r8 ! Read from TRA (Trap Address) Register +#endif + ! + ! Is the trap argument >= 0x20? (TRA will be >= 0x80) + mov #0x7f, r9 + cmp/hi r9, r8 + bt/s 0f + mov #OFF_TRA, r9 + add r15, r9 + ! + mov.l r8, @r9 ! set TRA value to tra + sti + ! Call the system call handler through the table. + ! First check for bad syscall number + mov r3, r9 + mov.l 2f, r8 ! Number of syscalls + cmp/hs r8, r9 + get_current_thread_info r8, r10 + bf good_system_call +syscall_badsys: ! Bad syscall number + mov #-ENOSYS, r0 + bra resume_userspace + mov.l r0, @(OFF_R0,r15) ! Return value + ! +0: + bra debug_trap + nop + ! +good_system_call: ! Good syscall number + mov.l @(TI_FLAGS,r8), r8 + mov #_TIF_SYSCALL_TRACE, r10 + tst r10, r8 + bf syscall_trace_entry + ! +syscall_call: + shll2 r9 ! x4 + mov.l 3f, r8 ! Load the address of sys_call_table + add r8, r9 + mov.l @r9, r8 + jsr @r8 ! jump to specific syscall handler + nop + mov.l @(OFF_R0,r15), r12 ! save r0 + mov.l r0, @(OFF_R0,r15) ! save the return value + ! +syscall_exit: + cli + ! + get_current_thread_info r8, r0 + mov.l @(TI_FLAGS,r8), r0 ! current_thread_info->flags + tst #_TIF_ALLWORK_MASK, r0 + bf syscall_exit_work + bra __restore_all + nop + .align 2 +#if !defined(CONFIG_CPU_SH2) +1: .long TRA +#endif +2: .long NR_syscalls +3: .long sys_call_table +4: .long do_syscall_trace diff --git a/arch/sh/kernel/head.S b/arch/sh/kernel/head.S index f5f53d14f245..b5ff23264617 100644 --- a/arch/sh/kernel/head.S +++ b/arch/sh/kernel/head.S @@ -53,8 +53,10 @@ ENTRY(_stext) ldc r0, sr ! Initialize global interrupt mask mov #0, r0 +#ifdef CONFIG_CPU_HAS_SR_RB ldc r0, r6_bank - +#endif + /* * Prefetch if possible to reduce cache miss penalty. * @@ -71,8 +73,10 @@ ENTRY(_stext) mov #(THREAD_SIZE >> 8), r1 shll8 r1 ! r1 = THREAD_SIZE sub r1, r0 ! +#ifdef CONFIG_CPU_HAS_SR_RB ldc r0, r7_bank ! ... and initial thread_info - +#endif + ! Clear BSS area mov.l 3f, r1 add #4, r1 @@ -95,7 +99,11 @@ ENTRY(_stext) nop .balign 4 +#if defined(CONFIG_CPU_SH2) +1: .long 0x000000F0 ! IMASK=0xF +#else 1: .long 0x400080F0 ! MD=1, RB=0, BL=0, FD=1, IMASK=0xF +#endif 2: .long init_thread_union+THREAD_SIZE 3: .long __bss_start 4: .long _end