diff options
Diffstat (limited to 'arch/arc/include/asm/entry-compact.h')
| -rw-r--r-- | arch/arc/include/asm/entry-compact.h | 157 |
1 files changed, 116 insertions, 41 deletions
diff --git a/arch/arc/include/asm/entry-compact.h b/arch/arc/include/asm/entry-compact.h index 6dbf5cecc8cc..00946fe04c9b 100644 --- a/arch/arc/include/asm/entry-compact.h +++ b/arch/arc/include/asm/entry-compact.h @@ -7,7 +7,7 @@ * Stack switching code can no longer reliably rely on the fact that * if we are NOT in user mode, stack is switched to kernel mode. * e.g. L2 IRQ interrupted a L1 ISR which had not yet completed - * it's prologue including stack switching from user mode + * its prologue including stack switching from user mode * * Vineetg: Aug 28th 2008: Bug #94984 * -Zero Overhead Loop Context shd be cleared when entering IRQ/EXcp/Trap @@ -21,7 +21,7 @@ * r25 contains the kernel current task ptr * - Defined Stack Switching Macro to be reused in all intr/excp hdlrs * - Shaved off 11 instructions from RESTORE_ALL_INT1 by using the - * address Write back load ld.ab instead of seperate ld/add instn + * address Write back load ld.ab instead of separate ld/add instn * * Amit Bhor, Sameer Dhavale: Codito Technologies 2004 */ @@ -33,6 +33,91 @@ #include <asm/irqflags-compact.h> #include <asm/thread_info.h> /* For THREAD_SIZE */ +/* Note on the LD/ST addr modes with addr reg wback + * + * LD.a same as LD.aw + * + * LD.a reg1, [reg2, x] => Pre Incr + * Eff Addr for load = [reg2 + x] + * + * LD.ab reg1, [reg2, x] => Post Incr + * Eff Addr for load = [reg2] + */ + +.macro PUSHAX aux + lr r9, [\aux] + push r9 +.endm + +.macro POPAX aux + pop r9 + sr r9, [\aux] +.endm + +.macro SAVE_R0_TO_R12 + push r0 + push r1 + push r2 + push r3 + push r4 + push r5 + push r6 + push r7 + push r8 + push r9 + push r10 + push r11 + push r12 +.endm + +.macro RESTORE_R12_TO_R0 + pop r12 + pop r11 + pop r10 + pop r9 + pop r8 + pop r7 + pop r6 + pop r5 + pop r4 + pop r3 + pop r2 + pop r1 + pop r0 +.endm + +.macro SAVE_ABI_CALLEE_REGS + push r13 + push r14 + push r15 + push r16 + push r17 + push r18 + push r19 + push r20 + push r21 + push r22 + push r23 + push r24 + push r25 +.endm + +.macro RESTORE_ABI_CALLEE_REGS + pop r25 + pop r24 + pop r23 + pop r22 + pop r21 + pop r20 + pop r19 + pop r18 + pop r17 + pop r16 + pop r15 + pop r14 + pop r13 +.endm + /*-------------------------------------------------------------- * Switch to Kernel Mode stack if SP points to User Mode stack * @@ -58,7 +143,7 @@ * 2. L1 IRQ taken, ISR starts (CPU auto-switched to KERNEL mode) * 3. But before it could switch SP from USER to KERNEL stack * a L2 IRQ "Interrupts" L1 - * Thay way although L2 IRQ happened in Kernel mode, stack is still + * That way although L2 IRQ happened in Kernel mode, stack is still * not switched. * To handle this, we may need to switch stack even if in kernel mode * provided SP has values in range of USER mode stack ( < 0x7000_0000 ) @@ -88,7 +173,7 @@ GET_CURR_TASK_ON_CPU r9 - /* With current tsk in r9, get it's kernel mode stack base */ + /* With current tsk in r9, get its kernel mode stack base */ GET_TSK_STACK_BASE r9, r9 /* save U mode SP @ pt_regs->sp */ @@ -126,19 +211,11 @@ * to be saved again on kernel mode stack, as part of pt_regs. *-------------------------------------------------------------*/ .macro PROLOG_FREEUP_REG reg, mem -#ifndef ARC_USE_SCRATCH_REG - sr \reg, [ARC_REG_SCRATCH_DATA0] -#else st \reg, [\mem] -#endif .endm .macro PROLOG_RESTORE_REG reg, mem -#ifndef ARC_USE_SCRATCH_REG - lr \reg, [ARC_REG_SCRATCH_DATA0] -#else ld \reg, [\mem] -#endif .endm /*-------------------------------------------------------------- @@ -148,7 +225,7 @@ * * After this it is safe to call the "C" handlers *-------------------------------------------------------------*/ -.macro EXCEPTION_PROLOGUE +.macro EXCEPTION_PROLOGUE_KEEP_AE /* Need at least 1 reg to code the early exception prologue */ PROLOG_FREEUP_REG r9, @ex_saved_reg1 @@ -159,14 +236,6 @@ /* ARC700 doesn't provide auto-stack switching */ SWITCH_TO_KERNEL_STK -#ifdef CONFIG_ARC_CURR_IN_REG - /* Treat r25 as scratch reg (save on stack) and load with "current" */ - PUSH r25 - GET_CURR_TASK_ON_CPU r25 -#else - sub sp, sp, 4 -#endif - st.a r0, [sp, -8] /* orig_r0 needed for syscall (skip ECR slot) */ sub sp, sp, 4 /* skip pt_regs->sp, already saved above */ @@ -186,7 +255,23 @@ PUSHAX erbta lr r10, [ecr] - st r10, [sp, PT_event] /* EV_Trap expects r10 to have ECR */ + st r10, [sp, PT_event] + +#ifdef CONFIG_ARC_CURR_IN_REG + /* gp already saved on stack: now load with "current" */ + GET_CURR_TASK_ON_CPU gp +#endif + ; OUTPUT: r10 has ECR expected by EV_Trap +.endm + +.macro EXCEPTION_PROLOGUE + + EXCEPTION_PROLOGUE_KEEP_AE ; return ECR in r10 + + lr r0, [efa] + mov r1, sp + + FAKE_RET_FROM_EXCPN ; clobbers r9 .endm /*-------------------------------------------------------------- @@ -197,7 +282,7 @@ * NOTE: * * It is recommended that lp_count/ilink1/ilink2 not be used as a dest reg - * for memory load operations. If used in that way interrupts are deffered + * for memory load operations. If used in that way interrupts are deferred * by hardware and that is not good. *-------------------------------------------------------------*/ .macro EXCEPTION_EPILOGUE @@ -216,11 +301,8 @@ POP gp RESTORE_R12_TO_R0 -#ifdef CONFIG_ARC_CURR_IN_REG - ld r25, [sp, 12] -#endif ld sp, [sp] /* restore original sp */ - /* orig_r0, ECR, user_r25 skipped automatically */ + /* orig_r0, ECR skipped automatically */ .endm /* Dummy ECR values for Interrupts */ @@ -237,15 +319,8 @@ SWITCH_TO_KERNEL_STK -#ifdef CONFIG_ARC_CURR_IN_REG - /* Treat r25 as scratch reg (save on stack) and load with "current" */ - PUSH r25 - GET_CURR_TASK_ON_CPU r25 -#else - sub sp, sp, 4 -#endif - PUSH 0x003\LVL\()abcd /* Dummy ECR */ + st.a 0x003\LVL\()abcd, [sp, -4] /* Dummy ECR */ sub sp, sp, 8 /* skip orig_r0 (not needed) skip pt_regs->sp, already saved above */ @@ -263,6 +338,10 @@ PUSHAX lp_start PUSHAX bta_l\LVL\() +#ifdef CONFIG_ARC_CURR_IN_REG + /* gp already saved on stack: now load with "current" */ + GET_CURR_TASK_ON_CPU gp +#endif .endm /*-------------------------------------------------------------- @@ -271,7 +350,7 @@ * NOTE: * * It is recommended that lp_count/ilink1/ilink2 not be used as a dest reg - * for memory load operations. If used in that way interrupts are deffered + * for memory load operations. If used in that way interrupts are deferred * by hardware and that is not good. *-------------------------------------------------------------*/ .macro INTERRUPT_EPILOGUE LVL @@ -290,11 +369,7 @@ POP gp RESTORE_R12_TO_R0 -#ifdef CONFIG_ARC_CURR_IN_REG - ld r25, [sp, 12] -#endif - ld sp, [sp] /* restore original sp */ - /* orig_r0, ECR, user_r25 skipped automatically */ + ld sp, [sp] /* restore original sp; orig_r0, ECR skipped implicitly */ .endm /* Get thread_info of "current" tsk */ |