From: Yoshinori Sato Date: Sun, 5 Nov 2006 06:58:47 +0000 (+0900) Subject: sh: Wire up division and address error exceptions on SH-2A. X-Git-Tag: v2.6.20-rc1~34^2~20^2~32^2~41 X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=0983b31849bbe1fe82520947acc1bec97c457d4b;p=linux-2.6 sh: Wire up division and address error exceptions on SH-2A. SH-2A has special division hardware as opposed to a full-fledged FPU, wire up the exception handlers for this. Signed-off-by: Yoshinori Sato Signed-off-by: Paul Mundt --- diff --git a/arch/sh/kernel/traps.c b/arch/sh/kernel/traps.c index 53dfa55f31..1edec2709e 100644 --- a/arch/sh/kernel/traps.c +++ b/arch/sh/kernel/traps.c @@ -33,8 +33,13 @@ #endif #ifdef CONFIG_CPU_SH2 -#define TRAP_RESERVED_INST 4 -#define TRAP_ILLEGAL_SLOT_INST 6 +# define TRAP_RESERVED_INST 4 +# define TRAP_ILLEGAL_SLOT_INST 6 +# define TRAP_ADDRESS_ERROR 9 +# ifdef CONFIG_CPU_SH2A +# define TRAP_DIVZERO_ERROR 17 +# define TRAP_DIVOVF_ERROR 18 +# endif #else #define TRAP_RESERVED_INST 12 #define TRAP_ILLEGAL_SLOT_INST 13 @@ -479,6 +484,14 @@ static int handle_unaligned_access(u16 instruction, struct pt_regs *regs) return ret; } +#ifdef CONFIG_CPU_HAS_SR_RB +#define lookup_exception_vector(x) \ + __asm__ __volatile__ ("stc r2_bank, %0\n\t" : "=r" ((x))) +#else +#define lookup_exception_vector(x) \ + __asm__ __volatile__ ("mov r4, %0\n\t" : "=r" ((x))) +#endif + /* * Handle various address error exceptions */ @@ -486,24 +499,37 @@ asmlinkage void do_address_error(struct pt_regs *regs, unsigned long writeaccess, unsigned long address) { - unsigned long error_code; + unsigned long error_code = 0; mm_segment_t oldfs; u16 instruction; int tmp; - asm volatile("stc r2_bank,%0": "=r" (error_code)); + /* Intentional ifdef */ +#ifdef CONFIG_CPU_HAS_SR_RB + lookup_exception_vector(error_code); +#endif oldfs = get_fs(); if (user_mode(regs)) { local_irq_enable(); current->thread.error_code = error_code; +#ifdef CONFIG_CPU_SH2 + /* + * On the SH-2, we only have a single vector for address + * errors, there's no differentiating between a load error + * and a store error. + */ + current->thread.trap_no = 9; +#else current->thread.trap_no = (writeaccess) ? 8 : 7; +#endif /* bad PC is not something we can fix */ if (regs->pc & 1) goto uspace_segv; +#ifndef CONFIG_CPU_SH2A set_fs(USER_DS); if (copy_from_user(&instruction, (u16 *)(regs->pc), 2)) { /* Argh. Fault on the instruction itself. @@ -518,6 +544,7 @@ asmlinkage void do_address_error(struct pt_regs *regs, if (tmp==0) return; /* sorted */ +#endif uspace_segv: printk(KERN_NOTICE "Killing process \"%s\" due to unaligned access\n", current->comm); @@ -526,6 +553,7 @@ asmlinkage void do_address_error(struct pt_regs *regs, if (regs->pc & 1) die("unaligned program counter", regs, error_code); +#ifndef CONFIG_CPU_SH2A set_fs(KERNEL_DS); if (copy_from_user(&instruction, (u16 *)(regs->pc), 2)) { /* Argh. Fault on the instruction itself. @@ -537,6 +565,10 @@ asmlinkage void do_address_error(struct pt_regs *regs, handle_unaligned_access(instruction, regs); set_fs(oldfs); +#else + printk(KERN_NOTICE "Killing process \"%s\" due to unaligned access\n", current->comm); + force_sig(SIGSEGV, current); +#endif } } @@ -569,6 +601,29 @@ int is_dsp_inst(struct pt_regs *regs) #define is_dsp_inst(regs) (0) #endif /* CONFIG_SH_DSP */ +#ifdef CONFIG_CPU_SH2A +asmlinkage void do_divide_error(unsigned long r4, unsigned long r5, + unsigned long r6, unsigned long r7, + struct pt_regs regs) +{ + siginfo_t info; + + current->thread.trap_no = r4; + current->thread.error_code = 0; + + switch (r4) { + case TRAP_DIVZERO_ERROR: + info.si_code = FPE_INTDIV; + break; + case TRAP_DIVOVF_ERROR: + info.si_code = FPE_INTOVF; + break; + } + + force_sig_info(SIGFPE, &info, current); +} +#endif + /* arch/sh/kernel/cpu/sh4/fpu.c */ extern int do_fpu_inst(unsigned short, struct pt_regs *); extern asmlinkage void do_fpu_state_restore(unsigned long r4, unsigned long r5, @@ -582,7 +637,7 @@ asmlinkage void do_reserved_inst(unsigned long r4, unsigned long r5, struct task_struct *tsk = current; #ifdef CONFIG_SH_FPU_EMU - unsigned short inst; + unsigned short inst = 0; int err; get_user(inst, (unsigned short*)regs.pc); @@ -604,7 +659,8 @@ asmlinkage void do_reserved_inst(unsigned long r4, unsigned long r5, } #endif - asm volatile("stc r2_bank, %0": "=r" (error_code)); + lookup_exception_vector(error_code); + local_irq_enable(); tsk->thread.error_code = error_code; tsk->thread.trap_no = TRAP_RESERVED_INST; @@ -663,7 +719,7 @@ asmlinkage void do_illegal_slot_inst(unsigned long r4, unsigned long r5, unsigned long error_code; struct task_struct *tsk = current; #ifdef CONFIG_SH_FPU_EMU - unsigned short inst; + unsigned short inst = 0; get_user(inst, (unsigned short *)regs.pc + 1); if (!do_fpu_inst(inst, ®s)) { @@ -675,7 +731,8 @@ asmlinkage void do_illegal_slot_inst(unsigned long r4, unsigned long r5, /* not a FPU inst. */ #endif - asm volatile("stc r2_bank, %0": "=r" (error_code)); + lookup_exception_vector(error_code); + local_irq_enable(); tsk->thread.error_code = error_code; tsk->thread.trap_no = TRAP_RESERVED_INST; @@ -689,7 +746,8 @@ asmlinkage void do_exception_error(unsigned long r4, unsigned long r5, struct pt_regs regs) { long ex; - asm volatile("stc r2_bank, %0" : "=r" (ex)); + + lookup_exception_vector(ex); die_if_kernel("exception", ®s, ex); } @@ -741,6 +799,10 @@ void *set_exception_table_vec(unsigned int vec, void *handler) return old_handler; } +extern asmlinkage void address_error_handler(unsigned long r4, unsigned long r5, + unsigned long r6, unsigned long r7, + struct pt_regs regs); + void __init trap_init(void) { set_exception_table_vec(TRAP_RESERVED_INST, do_reserved_inst); @@ -759,6 +821,14 @@ void __init trap_init(void) set_exception_table_evt(0x800, do_fpu_state_restore); set_exception_table_evt(0x820, do_fpu_state_restore); #endif + +#ifdef CONFIG_CPU_SH2 + set_exception_table_vec(TRAP_ADDRESS_ERROR, address_error_handler); +#endif +#ifdef CONFIG_CPU_SH2A + set_exception_table_vec(TRAP_DIVZERO_ERROR, do_divide_error); + set_exception_table_vec(TRAP_DIVOVF_ERROR, do_divide_error); +#endif /* Setup VBR for boot cpu */ per_cpu_trap_init();