diff --git a/arch/sh/kernel/Makefile b/arch/sh/kernel/Makefile index 2f6d2bcb1c93..ff30d7f58043 100644 --- a/arch/sh/kernel/Makefile +++ b/arch/sh/kernel/Makefile @@ -6,7 +6,8 @@ extra-y := head.o init_task.o vmlinux.lds obj-y := process.o signal.o traps.o irq.o \ ptrace.o setup.o time.o sys_sh.o semaphore.o \ - io.o io_generic.o sh_ksyms.o syscalls.o + io.o io_generic.o sh_ksyms.o syscalls.o \ + debugtraps.o obj-y += cpu/ timers/ obj-$(CONFIG_VSYSCALL) += vsyscall/ diff --git a/arch/sh/kernel/cpu/sh2/entry.S b/arch/sh/kernel/cpu/sh2/entry.S index d51fa5e9904a..8de48102ac85 100644 --- a/arch/sh/kernel/cpu/sh2/entry.S +++ b/arch/sh/kernel/cpu/sh2/entry.S @@ -206,7 +206,7 @@ trap_entry: #if defined(CONFIG_SH_STANDARD_BIOS) /* Unwind the stack and jmp to the debug entry */ -debug_kernel_fw: +ENTRY(sh_bios_handler) mov r15,r0 add #(22-4)*4-4,r0 ldc.l @r0+,gbr diff --git a/arch/sh/kernel/cpu/sh3/entry.S b/arch/sh/kernel/cpu/sh3/entry.S index 8c0dc2700c69..014ac37ca16a 100644 --- a/arch/sh/kernel/cpu/sh3/entry.S +++ b/arch/sh/kernel/cpu/sh3/entry.S @@ -173,7 +173,7 @@ call_dae: #if defined(CONFIG_SH_STANDARD_BIOS) /* Unwind the stack and jmp to the debug entry */ -debug_kernel_fw: +ENTRY(sh_bios_handler) mov.l @r15+, r0 mov.l @r15+, r1 mov.l @r15+, r2 diff --git a/arch/sh/kernel/debugtraps.S b/arch/sh/kernel/debugtraps.S new file mode 100644 index 000000000000..13b66746410a --- /dev/null +++ b/arch/sh/kernel/debugtraps.S @@ -0,0 +1,41 @@ +/* + * arch/sh/kernel/debugtraps.S + * + * Debug trap jump tables for SuperH + * + * Copyright (C) 2006 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. + */ +#include +#include + +#if !defined(CONFIG_SH_KGDB) +#define kgdb_handle_exception debug_trap_handler +#endif + +#if !defined(CONFIG_SH_STANDARD_BIOS) +#define sh_bios_handler debug_trap_handler +#endif + + .data + +ENTRY(debug_trap_table) + .long debug_trap_handler /* 0x30 */ + .long debug_trap_handler /* 0x31 */ + .long debug_trap_handler /* 0x32 */ + .long debug_trap_handler /* 0x33 */ + .long debug_trap_handler /* 0x34 */ + .long debug_trap_handler /* 0x35 */ + .long debug_trap_handler /* 0x36 */ + .long debug_trap_handler /* 0x37 */ + .long debug_trap_handler /* 0x38 */ + .long debug_trap_handler /* 0x39 */ + .long debug_trap_handler /* 0x3a */ + .long debug_trap_handler /* 0x3b */ + .long kgdb_handle_exception /* 0x3c */ + .long debug_trap_handler /* 0x3d */ + .long bug_trap_handler /* 0x3e */ + .long sh_bios_handler /* 0x3f */ diff --git a/arch/sh/kernel/entry-common.S b/arch/sh/kernel/entry-common.S index fc279aeb73ab..ab4ebb856c2a 100644 --- a/arch/sh/kernel/entry-common.S +++ b/arch/sh/kernel/entry-common.S @@ -54,79 +54,24 @@ # 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 */ -#ifdef CONFIG_SH_STANDARD_BIOS - bra debug_kernel_fw - nop -#endif -#endif /* CONFIG_SH_STANDARD_BIOS || CONFIG_SH_KGDB */ - - .align 2 -debug_trap: -#if defined(CONFIG_SH_STANDARD_BIOS) || defined(CONFIG_SH_KGDB) - mov r8, r0 - shlr2 r0 - cmp/eq #0x3f, r0 ! sh_bios() trap - bf 1f -#ifdef CONFIG_SH_KGDB - cmp/eq #0xff, r0 ! XXX: KGDB trap, fix for SH-2. - bf 1f -#endif - mov #OFF_SR, r0 - mov.l @(r0,r15), r0 ! get status register - shll r0 - shll r0 ! kernel space? - bt/s debug_kernel -1: -#endif - mov.l @r15, r0 ! Restore R0 value - mov.l 1f, r8 - jmp @r8 - nop .align 2 ENTRY(exception_error) ! #ifdef CONFIG_TRACE_IRQFLAGS - mov.l 3f, r0 + mov.l 2f, r0 jsr @r0 nop #endif sti - mov.l 2f, r0 + mov.l 1f, r0 jmp @r0 nop -! .align 2 -1: .long break_point_trap_software -2: .long do_exception_error +1: .long do_exception_error #ifdef CONFIG_TRACE_IRQFLAGS -3: .long trace_hardirqs_on +2: .long trace_hardirqs_on #endif .align 2 @@ -330,17 +275,32 @@ __restore_all: .align 2 1: .long restore_all - .align 2 -not_syscall_tra: - bra debug_trap - nop - .align 2 syscall_badsys: ! Bad syscall number mov #-ENOSYS, r0 bra resume_userspace mov.l r0, @(OFF_R0,r15) ! Return value - + +/* + * The main debug trap handler. + * + * r8=TRA (not the trap number!) + * + * Note: This assumes that the trapa value is left in its original + * form (without the shlr2 shift) so the calculation for the jump + * call table offset remains a simple in place mask. + */ +debug_trap: + mov r8, r0 + and #(0xf << 2), r0 + mov.l 1f, r8 + add r0, r8 + mov.l @r8, r8 + jmp @r8 + nop + + .align 2 +1: .long debug_trap_table /* * Syscall interface: @@ -348,17 +308,19 @@ syscall_badsys: ! Bad syscall number * Syscall #: R3 * Arguments #0 to #3: R4--R7 * Arguments #4 to #6: R0, R1, R2 - * TRA: (number of arguments + 0x10) x 4 + * TRA: (number of arguments + ABI revision) 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. + * (TRA>>2) Purpose + * -------- ------- + * 0x00-0x0f original SH-3/4 syscall ABI (not in general use). + * 0x10-0x1f general SH-3/4 syscall ABI. + * 0x20-0x2f syscall ABI for SH-2 parts. + * 0x30-0x3f debug traps used by the kernel. + * 0x40-0xff Not supported by all parts, so left unhandled. * * 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" @@ -375,17 +337,22 @@ ret_from_fork: nop .align 2 1: .long schedule_tail - ! + +/* + * The poorly named main trapa decode and dispatch routine, for + * system calls and debug traps through their respective jump tables. + */ 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 + /* + * Check the trap type + */ + mov #((0x20 << 2) - 1), r9 cmp/hi r9, r8 - bt/s not_syscall_tra + bt/s debug_trap ! it's a debug trap.. mov #OFF_TRA, r9 add r15, r9 mov.l r8, @r9 ! set TRA value to tra diff --git a/arch/sh/kernel/kgdb_stub.c b/arch/sh/kernel/kgdb_stub.c index 9c6315f0335d..d8927d85492e 100644 --- a/arch/sh/kernel/kgdb_stub.c +++ b/arch/sh/kernel/kgdb_stub.c @@ -1323,8 +1323,11 @@ static void kgdb_command_loop(const int excep_code, const int trapa_value) } /* There has been an exception, most likely a breakpoint. */ -void kgdb_handle_exception(struct pt_regs *regs) +asmlinkage void kgdb_handle_exception(unsigned long r4, unsigned long r5, + unsigned long r6, unsigned long r7, + struct pt_regs __regs) { + struct pt_regs *regs = RELOC_HIDE(&__regs, 0); int excep_code, vbr_val; int count; int trapa_value = ctrl_inl(TRA); @@ -1368,8 +1371,6 @@ void kgdb_handle_exception(struct pt_regs *regs) vbr_val = trap_registers.vbr; asm("ldc %0, vbr": :"r"(vbr_val)); - - return; } /* Trigger a breakpoint by function */ diff --git a/arch/sh/kernel/process.c b/arch/sh/kernel/process.c index 486c06e18033..cc8f306fd682 100644 --- a/arch/sh/kernel/process.c +++ b/arch/sh/kernel/process.c @@ -493,9 +493,27 @@ asmlinkage void break_point_trap(void) force_sig(SIGTRAP, current); } -asmlinkage void break_point_trap_software(unsigned long r4, unsigned long r5, - unsigned long r6, unsigned long r7, - struct pt_regs __regs) +/* + * Generic trap handler. + */ +asmlinkage void debug_trap_handler(unsigned long r4, unsigned long r5, + unsigned long r6, unsigned long r7, + struct pt_regs __regs) +{ + struct pt_regs *regs = RELOC_HIDE(&__regs, 0); + + /* Rewind */ + regs->pc -= 2; + + force_sig(SIGTRAP, current); +} + +/* + * Special handler for BUG() traps. + */ +asmlinkage void bug_trap_handler(unsigned long r4, unsigned long r5, + unsigned long r6, unsigned long r7, + struct pt_regs __regs) { struct pt_regs *regs = RELOC_HIDE(&__regs, 0); diff --git a/include/asm-sh/kgdb.h b/include/asm-sh/kgdb.h index 7b26f53fe343..0095c665d272 100644 --- a/include/asm-sh/kgdb.h +++ b/include/asm-sh/kgdb.h @@ -85,10 +85,10 @@ extern int setjmp(jmp_buf __jmpb); #define KGDB_PRINTK(...) printk("KGDB: " __VA_ARGS__) /* Forced breakpoint */ -#define BREAKPOINT() do { \ - if (kgdb_enabled) { \ - asm volatile("trapa #0xff"); \ - } \ +#define BREAKPOINT() \ +do { \ + if (kgdb_enabled) \ + __asm__ __volatile__("trapa #0x3c"); \ } while (0) /* KGDB should be able to flush all kernel text space */