diff options
-rw-r--r-- | arch/arc/include/asm/arcregs.h | 4 | ||||
-rw-r--r-- | arch/arc/include/asm/entry.h | 31 | ||||
-rw-r--r-- | arch/arc/include/asm/ptrace.h | 36 | ||||
-rw-r--r-- | arch/arc/kernel/asm-offsets.c | 2 | ||||
-rw-r--r-- | arch/arc/kernel/entry.S | 21 | ||||
-rw-r--r-- | arch/arc/kernel/kgdb.c | 2 | ||||
-rw-r--r-- | arch/arc/kernel/process.c | 2 | ||||
-rw-r--r-- | arch/arc/kernel/troubleshoot.c | 12 |
8 files changed, 53 insertions, 57 deletions
diff --git a/arch/arc/include/asm/arcregs.h b/arch/arc/include/asm/arcregs.h index 122e9af46824..355cb470c2a4 100644 --- a/arch/arc/include/asm/arcregs.h +++ b/arch/arc/include/asm/arcregs.h @@ -60,6 +60,7 @@ #define ECR_V_ITLB_MISS 0x21 #define ECR_V_DTLB_MISS 0x22 #define ECR_V_PROTV 0x23 +#define ECR_V_TRAP 0x25 /* Protection Violation Exception Cause Code Values */ #define ECR_C_PROTV_INST_FETCH 0x00 @@ -77,6 +78,9 @@ #define ECR_C_BIT_DTLB_LD_MISS 8 #define ECR_C_BIT_DTLB_ST_MISS 9 +/* Dummy ECR values for Interrupts */ +#define event_IRQ1 0x0031abcd +#define event_IRQ2 0x0032abcd /* Auxiliary registers */ #define AUX_IDENTITY 4 diff --git a/arch/arc/include/asm/entry.h b/arch/arc/include/asm/entry.h index de01bc842a9a..8943c028d4bb 100644 --- a/arch/arc/include/asm/entry.h +++ b/arch/arc/include/asm/entry.h @@ -309,7 +309,7 @@ #endif /* Save Pre Intr/Exception User SP on kernel stack */ - st.a sp, [r9, -16] ; Make room for orig_r0, orig_r8, user_r25 + st.a sp, [r9, -16] ; Make room for orig_r0, ECR, user_r25 /* CAUTION: * SP should be set at the very end when we are done with everything @@ -391,9 +391,10 @@ * Note that syscalls are implemented via TRAP which is also a exception * from CPU's point of view *-------------------------------------------------------------*/ -.macro SAVE_ALL_EXCEPTION marker +.macro SAVE_ALL_SYS - st \marker, [sp, 8] /* orig_r8 */ + lr r9, [ecr] + st r9, [sp, 8] /* ECR */ st r0, [sp, 4] /* orig_r0, needed only for sys calls */ /* Restore r9 used to code the early prologue */ @@ -412,20 +413,6 @@ .endm /*-------------------------------------------------------------- - * Save scratch regs for exceptions - *-------------------------------------------------------------*/ -.macro SAVE_ALL_SYS - SAVE_ALL_EXCEPTION orig_r8_IS_EXCPN -.endm - -/*-------------------------------------------------------------- - * Save scratch regs for sys calls - *-------------------------------------------------------------*/ -.macro SAVE_ALL_TRAP - SAVE_ALL_EXCEPTION orig_r8_IS_SCALL -.endm - -/*-------------------------------------------------------------- * Restore all registers used by system call or Exceptions * SP should always be pointing to the next free stack element * when entering this macro. @@ -452,7 +439,7 @@ RESTORE_R12_TO_R0 ld sp, [sp] /* restore original sp */ - /* orig_r0, orig_r8, user_r25 skipped automatically */ + /* orig_r0, ECR, user_r25 skipped automatically */ .endm @@ -469,7 +456,7 @@ #endif /* now we are ready to save the remaining context :) */ - st orig_r8_IS_IRQ1, [sp, 8] /* Event Type */ + st event_IRQ1, [sp, 8] /* Dummy ECR */ st 0, [sp, 4] /* orig_r0 , N/A for IRQ */ SAVE_R0_TO_R12 @@ -494,7 +481,7 @@ ld r9, [@int2_saved_reg] /* now we are ready to save the remaining context :) */ - st orig_r8_IS_IRQ2, [sp, 8] /* Event Type */ + st event_IRQ2, [sp, 8] /* Dummy ECR */ st 0, [sp, 4] /* orig_r0 , N/A for IRQ */ SAVE_R0_TO_R12 @@ -535,7 +522,7 @@ RESTORE_R12_TO_R0 ld sp, [sp] /* restore original sp */ - /* orig_r0, orig_r8, user_r25 skipped automatically */ + /* orig_r0, ECR, user_r25 skipped automatically */ .endm .macro RESTORE_ALL_INT2 @@ -554,7 +541,7 @@ RESTORE_R12_TO_R0 ld sp, [sp] /* restore original sp */ - /* orig_r0, orig_r8, user_r25 skipped automatically */ + /* orig_r0, ECR, user_r25 skipped automatically */ .endm diff --git a/arch/arc/include/asm/ptrace.h b/arch/arc/include/asm/ptrace.h index 7b2de6f7025a..c9938e7a7dbd 100644 --- a/arch/arc/include/asm/ptrace.h +++ b/arch/arc/include/asm/ptrace.h @@ -44,15 +44,24 @@ struct pt_regs { long sp; /* user/kernel sp depending on where we came from */ long orig_r0; - /*to distinguish bet excp, syscall, irq */ + /* + * To distinguish bet excp, syscall, irq + * For traps and exceptions, Exception Cause Register. + * ECR: <00> <VV> <CC> <PP> + * Last word used by Linux for extra state mgmt (syscall-restart) + * For interrupts, use artificial ECR values to note current prio-level + */ union { + struct { #ifdef CONFIG_CPU_BIG_ENDIAN - /* so that assembly code is same for LE/BE */ - unsigned long orig_r8:16, event:16; + unsigned long state:8, ecr_vec:8, + ecr_cause:8, ecr_param:8; #else - unsigned long event:16, orig_r8:16; + unsigned long ecr_param:8, ecr_cause:8, + ecr_vec:8, state:8; #endif - long orig_r8_word; + }; + unsigned long event; }; long user_r25; @@ -94,11 +103,13 @@ struct callee_regs { /* return 1 if PC in delay slot */ #define delay_mode(regs) ((regs->status32 & STATUS_DE_MASK) == STATUS_DE_MASK) -#define in_syscall(regs) (regs->event & orig_r8_IS_SCALL) -#define in_brkpt_trap(regs) (regs->event & orig_r8_IS_BRKPT) +#define in_syscall(regs) ((regs->ecr_vec == ECR_V_TRAP) && !regs->ecr_param) +#define in_brkpt_trap(regs) ((regs->ecr_vec == ECR_V_TRAP) && regs->ecr_param) -#define syscall_wont_restart(regs) (regs->event |= orig_r8_IS_SCALL_RESTARTED) -#define syscall_restartable(regs) !(regs->event & orig_r8_IS_SCALL_RESTARTED) +#define STATE_SCALL_RESTARTED 0x01 + +#define syscall_wont_restart(reg) (reg->state |= STATE_SCALL_RESTARTED) +#define syscall_restartable(reg) !(reg->state & STATE_SCALL_RESTARTED) #define current_pt_regs() \ ({ \ @@ -115,11 +126,4 @@ static inline long regs_return_value(struct pt_regs *regs) #endif /* !__ASSEMBLY__ */ -#define orig_r8_IS_SCALL 0x0001 -#define orig_r8_IS_SCALL_RESTARTED 0x0002 -#define orig_r8_IS_BRKPT 0x0004 -#define orig_r8_IS_EXCPN 0x0008 -#define orig_r8_IS_IRQ1 0x0010 -#define orig_r8_IS_IRQ2 0x0020 - #endif /* __ASM_PTRACE_H */ diff --git a/arch/arc/kernel/asm-offsets.c b/arch/arc/kernel/asm-offsets.c index 75f05b83d77d..6c3aa0edb9b5 100644 --- a/arch/arc/kernel/asm-offsets.c +++ b/arch/arc/kernel/asm-offsets.c @@ -46,7 +46,7 @@ int main(void) BLANK(); DEFINE(PT_status32, offsetof(struct pt_regs, status32)); - DEFINE(PT_orig_r8, offsetof(struct pt_regs, orig_r8_word)); + DEFINE(PT_event, offsetof(struct pt_regs, event)); DEFINE(PT_sp, offsetof(struct pt_regs, sp)); DEFINE(PT_r0, offsetof(struct pt_regs, r0)); DEFINE(PT_r1, offsetof(struct pt_regs, r1)); diff --git a/arch/arc/kernel/entry.S b/arch/arc/kernel/entry.S index fd5f9160bbd2..fb0fe3265637 100644 --- a/arch/arc/kernel/entry.S +++ b/arch/arc/kernel/entry.S @@ -142,7 +142,7 @@ VECTOR reserved ; Reserved Exceptions .endr #include <linux/linkage.h> /* ARC_{EXTRY,EXIT} */ -#include <asm/entry.h> /* SAVE_ALL_{INT1,INT2,TRAP...} */ +#include <asm/entry.h> /* SAVE_ALL_{INT1,INT2,SYS...} */ #include <asm/errno.h> #include <asm/arcregs.h> #include <asm/irqflags.h> @@ -495,8 +495,6 @@ tracesys_exit: trap_with_param: ; stop_pc info by gdb needs this info - stw orig_r8_IS_BRKPT, [sp, PT_orig_r8] - mov r0, r12 lr r1, [efa] mov r2, sp @@ -541,7 +539,7 @@ ARC_ENTRY EV_Trap lr r9, [erstatus] SWITCH_TO_KERNEL_STK - SAVE_ALL_TRAP + SAVE_ALL_SYS ;------- (4) What caused the Trap -------------- lr r12, [ecr] @@ -696,28 +694,33 @@ not_exception: #ifdef CONFIG_ARC_COMPACT_IRQ_LEVELS + ; Level 2 interrupt return Path - from hardware standpoint bbit0 r10, STATUS_A2_BIT, not_level2_interrupt ;------------------------------------------------------------------ + ; However the context returning might not have taken L2 intr itself + ; e.g. Task'A' user-code -> L2 intr -> schedule -> 'B' user-code ret + ; Special considerations needed for the context which took L2 intr + + ld r9, [sp, PT_event] ; Ensure this is L2 intr context + brne r9, event_IRQ2, 149f + + ;------------------------------------------------------------------ ; if L2 IRQ interrupted a L1 ISR, we'd disbaled preemption earlier ; so that sched doesnt move to new task, causing L1 to be delayed ; undeterministically. Now that we've achieved that, lets reset ; things to what they were, before returning from L2 context ;---------------------------------------------------------------- - ldw r9, [sp, PT_orig_r8] ; get orig_r8 to make sure it is - brne r9, orig_r8_IS_IRQ2, 149f ; infact a L2 ISR ret path - ld r9, [sp, PT_status32] ; get statu32_l2 (saved in pt_regs) bbit0 r9, STATUS_A1_BIT, 149f ; L1 not active when L2 IRQ, so normal - ; A1 is set in status32_l2 ; decrement thread_info->preempt_count (re-enable preemption) GET_CURR_THR_INFO_FROM_SP r10 ld r9, [r10, THREAD_INFO_PREEMPT_COUNT] ; paranoid check, given A1 was active when A2 happened, preempt count - ; must not be 0 beccause we would have incremented it. + ; must not be 0 because we would have incremented it. ; If this does happen we simply HALT as it means a BUG !!! cmp r9, 0 bnz 2f diff --git a/arch/arc/kernel/kgdb.c b/arch/arc/kernel/kgdb.c index 52bdc83c1495..84f1bb8208b4 100644 --- a/arch/arc/kernel/kgdb.c +++ b/arch/arc/kernel/kgdb.c @@ -181,7 +181,7 @@ void kgdb_trap(struct pt_regs *regs, int param) * with trap_s 4 (compiled) breakpoints, continuation needs to * start after the breakpoint. */ - if (param == 3) + if (regs->ecr_param == 3) instruction_pointer(regs) -= BREAK_INSTR_SIZE; kgdb_handle_exception(1, SIGTRAP, 0, regs); diff --git a/arch/arc/kernel/process.c b/arch/arc/kernel/process.c index a3cc6a577039..07a3a968fe49 100644 --- a/arch/arc/kernel/process.c +++ b/arch/arc/kernel/process.c @@ -76,7 +76,7 @@ asmlinkage void ret_from_fork(void); * ------------------ * | SP | * | orig_r0 | - * | orig_r8 | + * | event/ECR | * | user_r25 | * ------------------ <===== END of PAGE */ diff --git a/arch/arc/kernel/troubleshoot.c b/arch/arc/kernel/troubleshoot.c index 31a5d8905e1a..977464126be9 100644 --- a/arch/arc/kernel/troubleshoot.c +++ b/arch/arc/kernel/troubleshoot.c @@ -117,17 +117,16 @@ static void show_faulting_vma(unsigned long address, char *buf) static void show_ecr_verbose(struct pt_regs *regs) { - unsigned int vec, cause_code, cause_reg; + unsigned int vec, cause_code; unsigned long address; - cause_reg = current->thread.cause_code; - pr_info("\n[ECR ]: 0x%08x => ", cause_reg); + pr_info("\n[ECR ]: 0x%08lx => ", regs->event); /* For Data fault, this is data address not instruction addr */ address = current->thread.fault_address; - vec = cause_reg >> 16; - cause_code = (cause_reg >> 8) & 0xFF; + vec = regs->ecr_vec; + cause_code = regs->ecr_cause; /* For DTLB Miss or ProtV, display the memory involved too */ if (vec == ECR_V_DTLB_MISS) { @@ -174,8 +173,7 @@ void show_regs(struct pt_regs *regs) print_task_path_n_nm(tsk, buf); show_regs_print_info(KERN_INFO); - if (current->thread.cause_code) - show_ecr_verbose(regs); + show_ecr_verbose(regs); pr_info("[EFA ]: 0x%08lx\n[BLINK ]: %pS\n[ERET ]: %pS\n", current->thread.fault_address, |