diff options
Diffstat (limited to 'arch/arc')
| -rw-r--r-- | arch/arc/include/asm/entry-compact.h | 306 | ||||
| -rw-r--r-- | arch/arc/include/asm/entry.h | 300 | ||||
| -rw-r--r-- | arch/arc/kernel/Makefile | 4 | ||||
| -rw-r--r-- | arch/arc/kernel/entry-compact.S | 393 | ||||
| -rw-r--r-- | arch/arc/kernel/entry.S | 389 |
5 files changed, 711 insertions, 681 deletions
diff --git a/arch/arc/include/asm/entry-compact.h b/arch/arc/include/asm/entry-compact.h new file mode 100644 index 000000000000..6c0a81b598d2 --- /dev/null +++ b/arch/arc/include/asm/entry-compact.h @@ -0,0 +1,306 @@ +/* + * Copyright (C) 2014-15 Synopsys, Inc. (www.synopsys.com) + * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com) + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * Vineetg: March 2009 (Supporting 2 levels of Interrupts) + * 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 + * + * Vineetg: Aug 28th 2008: Bug #94984 + * -Zero Overhead Loop Context shd be cleared when entering IRQ/EXcp/Trap + * Normally CPU does this automatically, however when doing FAKE rtie, + * we also need to explicitly do this. The problem in macros + * FAKE_RET_FROM_EXCPN and FAKE_RET_FROM_EXCPN_LOCK_IRQ was that this bit + * was being "CLEARED" rather then "SET". Actually "SET" clears ZOL context + * + * Vineetg: May 5th 2008 + * -Modified CALLEE_REG save/restore macros to handle the fact that + * 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 + * + * Amit Bhor, Sameer Dhavale: Codito Technologies 2004 + */ + +#ifndef __ASM_ARC_ENTRY_COMPACT_H +#define __ASM_ARC_ENTRY_COMPACT_H + +#include <asm/asm-offsets.h> +#include <asm/thread_info.h> /* For THREAD_SIZE */ + +/*-------------------------------------------------------------- + * Switch to Kernel Mode stack if SP points to User Mode stack + * + * Entry : r9 contains pre-IRQ/exception/trap status32 + * Exit : SP is set to kernel mode stack pointer + * If CURR_IN_REG, r25 set to "current" task pointer + * Clobbers: r9 + *-------------------------------------------------------------*/ + +.macro SWITCH_TO_KERNEL_STK + + /* User Mode when this happened ? Yes: Proceed to switch stack */ + bbit1 r9, STATUS_U_BIT, 88f + + /* OK we were already in kernel mode when this event happened, thus can + * assume SP is kernel mode SP. _NO_ need to do any stack switching + */ + +#ifdef CONFIG_ARC_COMPACT_IRQ_LEVELS + /* However.... + * If Level 2 Interrupts enabled, we may end up with a corner case: + * 1. User Task executing + * 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 + * 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 ) + */ + brlo sp, VMALLOC_START, 88f + + /* TODO: vineetg: + * We need to be a bit more cautious here. What if a kernel bug in + * L1 ISR, caused SP to go whaco (some small value which looks like + * USER stk) and then we take L2 ISR. + * Above brlo alone would treat it as a valid L1-L2 sceanrio + * instead of shouting alound + * The only feasible way is to make sure this L2 happened in + * L1 prelogue ONLY i.e. ilink2 is less than a pre-set marker in + * L1 ISR before it switches stack + */ + +#endif + + /* Save Pre Intr/Exception KERNEL MODE SP on kernel stack + * safe-keeping not really needed, but it keeps the epilogue code + * (SP restore) simpler/uniform. + */ + b.d 66f + mov r9, sp + +88: /*------Intr/Ecxp happened in user mode, "switch" stack ------ */ + + GET_CURR_TASK_ON_CPU r9 + + /* With current tsk in r9, get it's kernel mode stack base */ + GET_TSK_STACK_BASE r9, r9 + +66: +#ifdef CONFIG_ARC_CURR_IN_REG + /* + * Treat r25 as scratch reg, save it on stack first + * Load it with current task pointer + */ + st r25, [r9, -4] + GET_CURR_TASK_ON_CPU r25 +#endif + + /* Save Pre Intr/Exception User SP on kernel stack */ + 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 + * In case of 2 levels of interrupt we depend on value of SP to assume + * that everything else is done (loading r25 etc) + */ + + /* set SP to point to kernel mode stack */ + mov sp, r9 + + /* ----- Stack Switched to kernel Mode, Now save REG FILE ----- */ + +.endm + +/*------------------------------------------------------------ + * "FAKE" a rtie to return from CPU Exception context + * This is to re-enable Exceptions within exception + * Look at EV_ProtV to see how this is actually used + *-------------------------------------------------------------*/ + +.macro FAKE_RET_FROM_EXCPN + + ld r9, [sp, PT_status32] + bic r9, r9, (STATUS_U_MASK|STATUS_DE_MASK) + bset r9, r9, STATUS_L_BIT + sr r9, [erstatus] + mov r9, 55f + sr r9, [eret] + + rtie +55: +.endm + +/*-------------------------------------------------------------- + * For early Exception/ISR Prologue, a core reg is temporarily needed to + * code the rest of prolog (stack switching). This is done by stashing + * it to memory (non-SMP case) or SCRATCH0 Aux Reg (SMP). + * + * Before saving the full regfile - this reg is restored back, only + * to be saved again on kernel mode stack, as part of pt_regs. + *-------------------------------------------------------------*/ +.macro PROLOG_FREEUP_REG reg, mem +#ifdef CONFIG_SMP + sr \reg, [ARC_REG_SCRATCH_DATA0] +#else + st \reg, [\mem] +#endif +.endm + +.macro PROLOG_RESTORE_REG reg, mem +#ifdef CONFIG_SMP + lr \reg, [ARC_REG_SCRATCH_DATA0] +#else + ld \reg, [\mem] +#endif +.endm + +/*-------------------------------------------------------------- + * Exception Entry prologue + * -Switches stack to K mode (if not already) + * -Saves the register file + * + * After this it is safe to call the "C" handlers + *-------------------------------------------------------------*/ +.macro EXCEPTION_PROLOGUE + + /* Need at least 1 reg to code the early exception prologue */ + PROLOG_FREEUP_REG r9, @ex_saved_reg1 + + /* U/K mode at time of exception (stack not switched if already K) */ + lr r9, [erstatus] + + /* ARC700 doesn't provide auto-stack switching */ + SWITCH_TO_KERNEL_STK + + 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 */ + PROLOG_RESTORE_REG r9, @ex_saved_reg1 + + SAVE_R0_TO_R12 + PUSH gp + PUSH fp + PUSH blink + PUSHAX eret + PUSHAX erstatus + PUSH lp_count + PUSHAX lp_end + PUSHAX lp_start + PUSHAX erbta +.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. + * + * 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 + * by hardware and that is not good. + *-------------------------------------------------------------*/ +.macro EXCEPTION_EPILOGUE + POPAX erbta + POPAX lp_start + POPAX lp_end + + POP r9 + mov lp_count, r9 ;LD to lp_count is not allowed + + POPAX erstatus + POPAX eret + POP blink + POP fp + POP gp + RESTORE_R12_TO_R0 + + ld sp, [sp] /* restore original sp */ + /* orig_r0, ECR, user_r25 skipped automatically */ +.endm + +/* Dummy ECR values for Interrupts */ +#define event_IRQ1 0x0031abcd +#define event_IRQ2 0x0032abcd + +.macro INTERRUPT_PROLOGUE LVL + + /* free up r9 as scratchpad */ + PROLOG_FREEUP_REG r9, @int\LVL\()_saved_reg + + /* Which mode (user/kernel) was the system in when intr occured */ + lr r9, [status32_l\LVL\()] + + SWITCH_TO_KERNEL_STK + + /* restore original r9 */ + PROLOG_RESTORE_REG r9, @int\LVL\()_saved_reg + + /* now we are ready to save the remaining context */ + st 0x003\LVL\()abcd, [sp, 8] /* Dummy ECR */ + st 0, [sp, 4] /* orig_r0 , N/A for IRQ */ + + SAVE_R0_TO_R12 + PUSH gp + PUSH fp + PUSH blink + PUSH ilink\LVL\() + PUSHAX status32_l\LVL\() + PUSH lp_count + PUSHAX lp_end + PUSHAX lp_start + PUSHAX bta_l\LVL\() +.endm + +/*-------------------------------------------------------------- + * Restore all registers used by interrupt handlers. + * + * 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 + * by hardware and that is not good. + *-------------------------------------------------------------*/ +.macro INTERRUPT_EPILOGUE LVL + POPAX bta_l\LVL\() + POPAX lp_start + POPAX lp_end + + POP r9 + mov lp_count, r9 ;LD to lp_count is not allowed + + POPAX status32_l\LVL\() + POP ilink\LVL\() + POP blink + POP fp + POP gp + RESTORE_R12_TO_R0 + + ld sp, [sp] /* restore original sp */ + /* orig_r0, ECR, user_r25 skipped automatically */ +.endm + +/* Get thread_info of "current" tsk */ +.macro GET_CURR_THR_INFO_FROM_SP reg + bic \reg, sp, (THREAD_SIZE - 1) +.endm + +/* Get CPU-ID of this core */ +.macro GET_CPU_ID reg + lr \reg, [identity] + lsr \reg, \reg, 8 + bmsk \reg, \reg, 7 +.endm + +#endif /* __ASM_ARC_ENTRY_COMPACT_H */ diff --git a/arch/arc/include/asm/entry.h b/arch/arc/include/asm/entry.h index 408a71378b5e..f61032c53d51 100644 --- a/arch/arc/include/asm/entry.h +++ b/arch/arc/include/asm/entry.h @@ -1,45 +1,23 @@ /* + * Copyright (C) 2014-15 Synopsys, Inc. (www.synopsys.com) * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com) * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License version 2 as * published by the Free Software Foundation. - * - * Vineetg: March 2009 (Supporting 2 levels of Interrupts) - * 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 - * - * Vineetg: Aug 28th 2008: Bug #94984 - * -Zero Overhead Loop Context shd be cleared when entering IRQ/EXcp/Trap - * Normally CPU does this automatically, however when doing FAKE rtie, - * we also need to explicitly do this. The problem in macros - * FAKE_RET_FROM_EXCPN and FAKE_RET_FROM_EXCPN_LOCK_IRQ was that this bit - * was being "CLEARED" rather then "SET". Actually "SET" clears ZOL context - * - * Vineetg: May 5th 2008 - * -Modified CALLEE_REG save/restore macros to handle the fact that - * 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 - * - * Amit Bhor, Sameer Dhavale: Codito Technologies 2004 */ #ifndef __ASM_ARC_ENTRY_H #define __ASM_ARC_ENTRY_H -#ifdef __ASSEMBLY__ #include <asm/unistd.h> /* For NR_syscalls defination */ -#include <asm/asm-offsets.h> #include <asm/arcregs.h> #include <asm/ptrace.h> #include <asm/processor.h> /* For VMALLOC_START */ -#include <asm/thread_info.h> /* For THREAD_SIZE */ #include <asm/mmu.h> +#include <asm/entry-compact.h> /* ISA specific bits */ + /* Note on the LD/ST addr modes with addr reg wback * * LD.a same as LD.aw @@ -240,117 +218,6 @@ .endm -/*-------------------------------------------------------------- - * Switch to Kernel Mode stack if SP points to User Mode stack - * - * Entry : r9 contains pre-IRQ/exception/trap status32 - * Exit : SP is set to kernel mode stack pointer - * If CURR_IN_REG, r25 set to "current" task pointer - * Clobbers: r9 - *-------------------------------------------------------------*/ - -.macro SWITCH_TO_KERNEL_STK - - /* User Mode when this happened ? Yes: Proceed to switch stack */ - bbit1 r9, STATUS_U_BIT, 88f - - /* OK we were already in kernel mode when this event happened, thus can - * assume SP is kernel mode SP. _NO_ need to do any stack switching - */ - -#ifdef CONFIG_ARC_COMPACT_IRQ_LEVELS - /* However.... - * If Level 2 Interrupts enabled, we may end up with a corner case: - * 1. User Task executing - * 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 - * 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 ) - */ - brlo sp, VMALLOC_START, 88f - - /* TODO: vineetg: - * We need to be a bit more cautious here. What if a kernel bug in - * L1 ISR, caused SP to go whaco (some small value which looks like - * USER stk) and then we take L2 ISR. - * Above brlo alone would treat it as a valid L1-L2 sceanrio - * instead of shouting alound - * The only feasible way is to make sure this L2 happened in - * L1 prelogue ONLY i.e. ilink2 is less than a pre-set marker in - * L1 ISR before it switches stack - */ - -#endif - - /* Save Pre Intr/Exception KERNEL MODE SP on kernel stack - * safe-keeping not really needed, but it keeps the epilogue code - * (SP restore) simpler/uniform. - */ - b.d 66f - mov r9, sp - -88: /*------Intr/Ecxp happened in user mode, "switch" stack ------ */ - - GET_CURR_TASK_ON_CPU r9 - - /* With current tsk in r9, get it's kernel mode stack base */ - GET_TSK_STACK_BASE r9, r9 - -66: -#ifdef CONFIG_ARC_CURR_IN_REG - /* - * Treat r25 as scratch reg, save it on stack first - * Load it with current task pointer - */ - st r25, [r9, -4] - GET_CURR_TASK_ON_CPU r25 -#endif - - /* Save Pre Intr/Exception User SP on kernel stack */ - 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 - * In case of 2 levels of interrupt we depend on value of SP to assume - * that everything else is done (loading r25 etc) - */ - - /* set SP to point to kernel mode stack */ - mov sp, r9 - - /* ----- Stack Switched to kernel Mode, Now save REG FILE ----- */ - -.endm - -/*------------------------------------------------------------ - * "FAKE" a rtie to return from CPU Exception context - * This is to re-enable Exceptions within exception - * Look at EV_ProtV to see how this is actually used - *-------------------------------------------------------------*/ - -.macro FAKE_RET_FROM_EXCPN - - ld r9, [sp, PT_status32] - bic r9, r9, (STATUS_U_MASK|STATUS_DE_MASK) - bset r9, r9, STATUS_L_BIT - sr r9, [erstatus] - mov r9, 55f - sr r9, [eret] - - rtie -55: -.endm - -/* - * @reg [OUT] &thread_info of "current" - */ -.macro GET_CURR_THR_INFO_FROM_SP reg - bic \reg, sp, (THREAD_SIZE - 1) -.endm - /* * @reg [OUT] thread_info->flags of "current" */ @@ -359,165 +226,6 @@ ld \reg, [\reg, THREAD_INFO_FLAGS] .endm -/*-------------------------------------------------------------- - * For early Exception/ISR Prologue, a core reg is temporarily needed to - * code the rest of prolog (stack switching). This is done by stashing - * it to memory (non-SMP case) or SCRATCH0 Aux Reg (SMP). - * - * Before saving the full regfile - this reg is restored back, only - * to be saved again on kernel mode stack, as part of pt_regs. - *-------------------------------------------------------------*/ -.macro PROLOG_FREEUP_REG reg, mem -#ifdef CONFIG_SMP - sr \reg, [ARC_REG_SCRATCH_DATA0] -#else - st \reg, [\mem] -#endif -.endm - -.macro PROLOG_RESTORE_REG reg, mem -#ifdef CONFIG_SMP - lr \reg, [ARC_REG_SCRATCH_DATA0] -#else - ld \reg, [\mem] -#endif -.endm - -/*-------------------------------------------------------------- - * Exception Entry prologue - * -Switches stack to K mode (if not already) - * -Saves the register file - * - * After this it is safe to call the "C" handlers - *-------------------------------------------------------------*/ -.macro EXCEPTION_PROLOGUE - - /* Need at least 1 reg to code the early exception prologue */ - PROLOG_FREEUP_REG r9, @ex_saved_reg1 - - /* U/K mode at time of exception (stack not switched if already K) */ - lr r9, [erstatus] - - /* ARC700 doesn't provide auto-stack switching */ - SWITCH_TO_KERNEL_STK - - 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 */ - PROLOG_RESTORE_REG r9, @ex_saved_reg1 - - SAVE_R0_TO_R12 - PUSH gp - PUSH fp - PUSH blink - PUSHAX eret - PUSHAX erstatus - PUSH lp_count - PUSHAX lp_end - PUSHAX lp_start - PUSHAX erbta -.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. - * - * 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 - * by hardware and that is not good. - *-------------------------------------------------------------*/ -.macro EXCEPTION_EPILOGUE - POPAX erbta - POPAX lp_start - POPAX lp_end - - POP r9 - mov lp_count, r9 ;LD to lp_count is not allowed - - POPAX erstatus - POPAX eret - POP blink - POP fp - POP gp - RESTORE_R12_TO_R0 - - ld sp, [sp] /* restore original sp */ - /* orig_r0, ECR, user_r25 skipped automatically */ -.endm - -/* Dummy ECR values for Interrupts */ -#define event_IRQ1 0x0031abcd -#define event_IRQ2 0x0032abcd - -.macro INTERRUPT_PROLOGUE LVL - - /* free up r9 as scratchpad */ - PROLOG_FREEUP_REG r9, @int\LVL\()_saved_reg - - /* Which mode (user/kernel) was the system in when intr occurred */ - lr r9, [status32_l\LVL\()] - - SWITCH_TO_KERNEL_STK - - /* restore original r9 */ - PROLOG_RESTORE_REG r9, @int\LVL\()_saved_reg - - /* now we are ready to save the remaining context */ - st 0x003\LVL\()abcd, [sp, 8] /* Dummy ECR */ - st 0, [sp, 4] /* orig_r0 , N/A for IRQ */ - - SAVE_R0_TO_R12 - PUSH gp - PUSH fp - PUSH blink - PUSH ilink\LVL\() - PUSHAX status32_l\LVL\() - PUSH lp_count - PUSHAX lp_end - PUSHAX lp_start - PUSHAX bta_l\LVL\() -.endm - -/*-------------------------------------------------------------- - * Restore all registers used by interrupt handlers. - * - * 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 - * by hardware and that is not good. - *-------------------------------------------------------------*/ -.macro INTERRUPT_EPILOGUE LVL - POPAX bta_l\LVL\() - POPAX lp_start - POPAX lp_end - - POP r9 - mov lp_count, r9 ;LD to lp_count is not allowed - - POPAX status32_l\LVL\() - POP ilink\LVL\() - POP blink - POP fp - POP gp - RESTORE_R12_TO_R0 - - ld sp, [sp] /* restore original sp */ - /* orig_r0, ECR, user_r25 skipped automatically */ -.endm - -/* Get CPU-ID of this core */ -.macro GET_CPU_ID reg - lr \reg, [identity] - lsr \reg, \reg, 8 - bmsk \reg, \reg, 7 -.endm - #ifdef CONFIG_SMP /*------------------------------------------------- @@ -586,6 +294,4 @@ #endif /* CONFIG_ARC_CURR_IN_REG */ -#endif /* __ASSEMBLY__ */ - #endif /* __ASM_ARC_ENTRY_H */ diff --git a/arch/arc/kernel/Makefile b/arch/arc/kernel/Makefile index 113f2033da9f..024a63e90b72 100644 --- a/arch/arc/kernel/Makefile +++ b/arch/arc/kernel/Makefile @@ -8,9 +8,9 @@ # Pass UTS_MACHINE for user_regset definition CFLAGS_ptrace.o += -DUTS_MACHINE='"$(UTS_MACHINE)"' -obj-y := arcksyms.o setup.o irq.o time.o reset.o ptrace.o entry.o process.o +obj-y := arcksyms.o setup.o irq.o time.o reset.o ptrace.o process.o devtree.o obj-y += signal.o traps.o sys.o troubleshoot.o stacktrace.o disasm.o clk.o -obj-y += devtree.o +obj-y += entry-compact.o obj-$(CONFIG_MODULES) += arcksyms.o module.o obj-$(CONFIG_SMP) += smp.o diff --git a/arch/arc/kernel/entry-compact.S b/arch/arc/kernel/entry-compact.S new file mode 100644 index 000000000000..bf611ec9a017 --- /dev/null +++ b/arch/arc/kernel/entry-compact.S @@ -0,0 +1,393 @@ +/* + * Low Level Interrupts/Traps/Exceptions(non-TLB) Handling for ARCompact ISA + * + * Copyright (C) 2014-15 Synopsys, Inc. (www.synopsys.com) + * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com) + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * vineetg: May 2011 + * -Userspace unaligned access emulation + * + * vineetg: Feb 2011 (ptrace low level code fixes) + * -traced syscall return code (r0) was not saved into pt_regs for restoring + * into user reg-file when traded task rets to user space. + * -syscalls needing arch-wrappers (mainly for passing sp as pt_regs) + * were not invoking post-syscall trace hook (jumping directly into + * ret_from_system_call) + * + * vineetg: Nov 2010: + * -Vector table jumps (@8 bytes) converted into branches (@4 bytes) + * -To maintain the slot size of 8 bytes/vector, added nop, which is + * not executed at runtime. + * + * vineetg: Nov 2009 (Everything needed for TIF_RESTORE_SIGMASK) + * -do_signal()invoked upon TIF_RESTORE_SIGMASK as well + * -Wrappers for sys_{,rt_}sigsuspend() nolonger needed as they don't + * need ptregs anymore + * + * Vineetg: Oct 2009 + * -In a rare scenario, Process gets a Priv-V exception and gets scheduled + * out. Since we don't do FAKE RTIE for Priv-V, CPU excpetion state remains + * active (AE bit enabled). This causes a double fault for a subseq valid + * exception. Thus FAKE RTIE needed in low level Priv-Violation handler. + * Instr Error could also cause similar scenario, so same there as well. + * + * Vineetg: March 2009 (Supporting 2 levels of Interrupts) + * + * Vineetg: Aug 28th 2008: Bug #94984 + * -Zero Overhead Loop Context shd be cleared when entering IRQ/EXcp/Trap + * Normally CPU does this automatically, however when doing FAKE rtie, + * we need to explicitly do this. The problem in macros + * FAKE_RET_FROM_EXCPN and FAKE_RET_FROM_EXCPN_LOCK_IRQ was that this bit + * was being "CLEARED" rather then "SET". Since it is Loop INHIBIT Bit, + * setting it and not clearing it clears ZOL context + * + * Vineetg: May 16th, 2008 + * - r25 now contains the Current Task when in kernel + * + * Vineetg: Dec 22, 2007 + * Minor Surgery of Low Level ISR to make it SMP safe + * - MMU_SCRATCH0 Reg used for freeing up r9 in Level 1 ISR + * - _current_task is made an array of NR_CPUS + * - Access of _current_task wrapped inside a macro so that if hardware + * team agrees for a dedicated reg, no other code is touched + * + * Amit Bhor, Rahul Trivedi, Kanika Nema, Sameer Dhavale : Codito Tech 2004 + */ + +#include <linux/errno.h> +#include <linux/linkage.h> /* {EXTRY,EXIT} */ +#include <asm/entry.h> +#include <asm/irqflags.h> + + .cpu A7 + +;############################ Vector Table ################################# + +.macro VECTOR lbl +#if 1 /* Just in case, build breaks */ + j \lbl +#else + b \lbl + nop +#endif +.endm + + .section .vector, "ax",@progbits + .align 4 + +/* Each entry in the vector table must occupy 2 words. Since it is a jump + * across sections (.vector to .text) we are gauranteed that 'j somewhere' + * will use the 'j limm' form of the intrsuction as long as somewhere is in + * a section other than .vector. + */ + +; ********* Critical System Events ********************** +VECTOR res_service ; 0x0, Restart Vector (0x0) +VECTOR mem_service ; 0x8, Mem exception (0x1) +VECTOR instr_service ; 0x10, Instrn Error (0x2) + +; ******************** Device ISRs ********************** +#ifdef CONFIG_ARC_IRQ3_LV2 +VECTOR handle_interrupt_level2 +#else +VECTOR handle_interrupt_level1 +#endif + +VECTOR handle_interrupt_level1 + +#ifdef CONFIG_ARC_IRQ5_LV2 +VECTOR handle_interrupt_level2 +#else +VECTOR handle_interrupt_level1 +#endif + +#ifdef CONFIG_ARC_IRQ6_LV2 +VECTOR handle_interrupt_level2 +#else +VECTOR handle_interrupt_level1 +#endif + +.rept 25 +VECTOR handle_interrupt_level1 ; Other devices +.endr + +/* FOR ARC600: timer = 0x3, uart = 0x8, emac = 0x10 */ + +; ******************** Exceptions ********************** +VECTOR EV_MachineCheck ; 0x100, Fatal Machine check (0x20) +VECTOR EV_TLBMissI ; 0x108, Intruction TLB miss (0x21) +VECTOR EV_TLBMissD ; 0x110, Data TLB miss (0x22) +VECTOR EV_TLBProtV ; 0x118, Protection Violation (0x23) + ; or Misaligned Access +VECTOR EV_PrivilegeV ; 0x120, Privilege Violation (0x24) +VECTOR EV_Trap ; 0x128, Trap exception (0x25) +VECTOR EV_Extension ; 0x130, Extn Intruction Excp (0x26) + +.rept 24 +VECTOR reserved ; Reserved Exceptions +.endr + + +;##################### Scratch Mem for IRQ stack switching ############# + +ARCFP_DATA int1_saved_reg + .align 32 + .type int1_saved_reg, @object + .size int1_saved_reg, 4 +int1_saved_reg: + .zero 4 + +/* Each Interrupt level needs its own scratch */ +#ifdef CONFIG_ARC_COMPACT_IRQ_LEVELS + +ARCFP_DATA int2_saved_reg + .type int2_saved_reg, @object + .size int2_saved_reg, 4 +int2_saved_reg: + .zero 4 + +#endif + +; --------------------------------------------- + .section .text, "ax",@progbits + +res_service: ; processor restart + flag 0x1 ; not implemented + nop + nop + +reserved: ; processor restart + rtie ; jump to processor initializations + +;##################### Interrupt Handling ############################## + +#ifdef CONFIG_ARC_COMPACT_IRQ_LEVELS +; --------------------------------------------- +; Level 2 ISR: Can interrupt a Level 1 ISR +; --------------------------------------------- +ENTRY(handle_interrupt_level2) + + INTERRUPT_PROLOGUE 2 + + ;------------------------------------------------------ + ; if L2 IRQ interrupted a L1 ISR, disable preemption + ;------------------------------------------------------ + + ld r9, [sp, PT_status32] ; get statu32_l2 (saved in pt_regs) + bbit0 r9, STATUS_A1_BIT, 1f ; L1 not active when L2 IRQ, so normal + + ; A1 is set in status32_l2 + ; bump thread_info->preempt_count (Disable preemption) + GET_CURR_THR_INFO_FROM_SP r10 + ld r9, [r10, THREAD_INFO_PREEMPT_COUNT] + add r9, r9, 1 + st r9, [r10, THREAD_INFO_PREEMPT_COUNT] + +1: + ;------------------------------------------------------ + ; setup params for Linux common ISR and invoke it + ;------------------------------------------------------ + lr r0, [icause2] + and r0, r0, 0x1f + + bl.d @arch_do_IRQ + mov r1, sp + + mov r8,0x2 + sr r8, [AUX_IRQ_LV12] ; clear bit in Sticky Status Reg + + b ret_from_exception + +END(handle_interrupt_level2) + +#endif + +; --------------------------------------------- +; Level 1 ISR +; --------------------------------------------- +ENTRY(handle_interrupt_level1) + + INTERRUPT_PROLOGUE 1 + + lr r0, [icause1] + and r0, r0, 0x1f + +#ifdef CONFIG_TRACE_IRQFLAGS + ; icause1 needs to be read early, before calling tracing, which + ; can clobber scratch regs, hence use of stack to stash it + push r0 + TRACE_ASM_IRQ_DISABLE + pop r0 +#endif + + bl.d @arch_do_IRQ + mov r1, sp + + mov r8,0x1 + sr r8, [AUX_IRQ_LV12] ; clear bit in Sticky Status Reg + + b ret_from_exception +END(handle_interrupt_level1) + +;################### Non TLB Exception Handling ############################# + +; --------------------------------------------- +; Protection Violation Exception Handler +; --------------------------------------------- + +ENTRY(EV_TLBProtV) + + EXCEPTION_PROLOGUE + + lr r2, [ecr] + lr r0, [efa] ; Faulting Data address (not part of pt_regs saved above) + + ; Exception auto-disables further Intr/exceptions. + ; Re-enable them by pretending to return from exception + ; (so rest of handler executes in pure K mode) + + FAKE_RET_FROM_EXCPN + + mov r1, sp ; Handle to pt_regs + + ;------ (5) Type of Protection Violation? ---------- + ; + ; ProtV Hardware Exception is triggered for Access Faults of 2 types + ; -Access Violaton : 00_23_(00|01|02|03)_00 + ; x r w r+w + ; -Unaligned Access : 00_23_04_00 + ; + bbit1 r2, ECR_C_BIT_PROTV_MISALIG_DATA, 4f + + ;========= (6a) Access Violation Processing ======== + bl do_page_fault + b ret_from_exception + + ;========== (6b) Non aligned access ============ +4: + + SAVE_CALLEE_SAVED_USER + mov r2, sp ; callee_regs + + bl do_misaligned_access + + ; TBD: optimize - do this only if a callee reg was involved + ; either a dst of emulated LD/ST or src with address-writeback + RESTORE_CALLEE_SAVED_USER + + b ret_from_exception + +END(EV_TLBProtV) + +; Wrapper for Linux page fault handler called from EV_TLBMiss* +; Very similar to ProtV handler case (6a) above, but avoids the extra checks +; for Misaligned access +; +ENTRY(call_do_page_fault) + + EXCEPTION_PROLOGUE + lr r0, [efa] ; Faulting Data address + mov r1, sp + FAKE_RET_FROM_EXCPN + + mov blink, ret_from_exception + b do_page_fault + +END(call_do_page_fault) + +;############# Common Handlers for ARCompact and ARCv2 ############## + +#include "entry.S" + +;############# Return from Intr/Excp/Trap (ARC Specifics) ############## +; +; Restore the saved sys context (common exit-path for EXCPN/IRQ/Trap) +; IRQ shd definitely not happen between now and rtie +; All 2 entry points to here already disable interrupts + +.Lrestore_regs: + + TRACE_ASM_IRQ_ENABLE + + lr r10, [status32] + + ; Restore REG File. In case multiple Events outstanding, + ; use the same priorty as rtie: EXCPN, L2 IRQ, L1 IRQ, None + ; Note that we use realtime STATUS32 (not pt_regs->status32) to + ; decide that. + + ; if Returning from Exception + bbit0 r10, STATUS_AE_BIT, not_exception + EXCEPTION_EPILOGUE + rtie + + ; Not Exception so maybe Interrupts (Level 1 or 2) + +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 an L1 ISR, we'd disabled preemption earlier + ; so that sched doesn't move to new task, causing L1 to be delayed + ; undeterministically. Now that we've achieved that, let's reset + ; things to what they were, before returning from L2 context + ;---------------------------------------------------------------- + + 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 + + ; 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 because we would have incremented it. + ; If this does happen we simply HALT as it means a BUG !!! + cmp r9, 0 + bnz 2f + flag 1 + +2: + sub r9, r9, 1 + st r9, [r10, THREAD_INFO_PREEMPT_COUNT] + +149: + ;return from level 2 + INTERRUPT_EPILOGUE 2 +debug_marker_l2: + rtie + +not_level2_interrupt: + +#endif + + bbit0 r10, STATUS_A1_BIT, not_level1_interrupt + + ;return from level 1 + INTERRUPT_EPILOGUE 1 +debug_marker_l1: + rtie + +not_level1_interrupt: + + ;this case is for syscalls or Exceptions (with fake rtie) + + EXCEPTION_EPILOGUE +debug_marker_syscall: + rtie diff --git a/arch/arc/kernel/entry.S b/arch/arc/kernel/entry.S index 286d7dc0723b..75cdc56351d9 100644 --- a/arch/arc/kernel/entry.S +++ b/arch/arc/kernel/entry.S @@ -1,60 +1,13 @@ /* - * Low Level Interrupts/Traps/Exceptions(non-TLB) Handling for ARC + * Common Low Level Interrupts/Traps/Exceptions(non-TLB) Handling for ARC + * (included from entry-<isa>.S * + * Copyright (C) 2014-15 Synopsys, Inc. (www.synopsys.com) * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com) * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License version 2 as * published by the Free Software Foundation. - * - * vineetg: May 2011 - * -Userspace unaligned access emulation - * - * vineetg: Feb 2011 (ptrace low level code fixes) - * -traced syscall return code (r0) was not saved into pt_regs for restoring - * into user reg-file when traded task rets to user space. - * -syscalls needing arch-wrappers (mainly for passing sp as pt_regs) - * were not invoking post-syscall trace hook (jumping directly into - * ret_from_system_call) - * - * vineetg: Nov 2010: - * -Vector table jumps (@8 bytes) converted into branches (@4 bytes) - * -To maintain the slot size of 8 bytes/vector, added nop, which is - * not executed at runtime. - * - * vineetg: Nov 2009 (Everything needed for TIF_RESTORE_SIGMASK) - * -do_signal()invoked upon TIF_RESTORE_SIGMASK as well - * -Wrappers for sys_{,rt_}sigsuspend() nolonger needed as they don't - * need ptregs anymore - * - * Vineetg: Oct 2009 - * -In a rare scenario, Process gets a Priv-V exception and gets scheduled - * out. Since we don't do FAKE RTIE for Priv-V, CPU excpetion state remains - * active (AE bit enabled). This causes a double fault for a subseq valid - * exception. Thus FAKE RTIE needed in low level Priv-Violation handler. - * Instr Error could also cause similar scenario, so same there as well. - * - * Vineetg: March 2009 (Supporting 2 levels of Interrupts) - * - * Vineetg: Aug 28th 2008: Bug #94984 - * -Zero Overhead Loop Context shd be cleared when entering IRQ/EXcp/Trap - * Normally CPU does this automatically, however when doing FAKE rtie, - * we need to explicitly do this. The problem in macros - * FAKE_RET_FROM_EXCPN and FAKE_RET_FROM_EXCPN_LOCK_IRQ was that this bit - * was being "CLEARED" rather then "SET". Since it is Loop INHIBIT Bit, - * setting it and not clearing it clears ZOL context - * - * Vineetg: May 16th, 2008 - * - r25 now contains the Current Task when in kernel - * - * Vineetg: Dec 22, 2007 - * Minor Surgery of Low Level ISR to make it SMP safe - * - MMU_SCRATCH0 Reg used for freeing up r9 in Level 1 ISR - * - _current_task is made an array of NR_CPUS - * - Access of _current_task wrapped inside a macro so that if hardware - * team agrees for a dedicated reg, no other code is touched - * - * Amit Bhor, Rahul Trivedi, Kanika Nema, Sameer Dhavale : Codito Tech 2004 */ /*------------------------------------------------------------------ @@ -67,187 +20,10 @@ * Global Pointer (gp) r26 * Frame Pointer (fp) r27 * Stack Pointer (sp) r28 - * Interrupt link register (ilink1) r29 - * Interrupt link register (ilink2) r30 * Branch link register (blink) r31 *------------------------------------------------------------------ */ - .cpu A7 - -;############################ Vector Table ################################# - -.macro VECTOR lbl -#if 1 /* Just in case, build breaks */ - j \lbl -#else - b \lbl - nop -#endif -.endm - - .section .vector, "ax",@progbits - .align 4 - -/* Each entry in the vector table must occupy 2 words. Since it is a jump - * across sections (.vector to .text) we are gauranteed that 'j somewhere' - * will use the 'j limm' form of the intrsuction as long as somewhere is in - * a section other than .vector. - */ - -; ********* Critical System Events ********************** -VECTOR res_service ; 0x0, Restart Vector (0x0) -VECTOR mem_service ; 0x8, Mem exception (0x1) -VECTOR instr_service ; 0x10, Instrn Error (0x2) - -; ******************** Device ISRs ********************** -#ifdef CONFIG_ARC_IRQ3_LV2 -VECTOR handle_interrupt_level2 -#else -VECTOR handle_interrupt_level1 -#endif - -VECTOR handle_interrupt_level1 - -#ifdef CONFIG_ARC_IRQ5_LV2 -VECTOR handle_interrupt_level2 -#else -VECTOR handle_interrupt_level1 -#endif - -#ifdef CONFIG_ARC_IRQ6_LV2 -VECTOR handle_interrupt_level2 -#else -VECTOR handle_interrupt_level1 -#endif - -.rept 25 -VECTOR handle_interrupt_level1 ; Other devices -.endr - -/* FOR ARC600: timer = 0x3, uart = 0x8, emac = 0x10 */ - -; ******************** Exceptions ********************** -VECTOR EV_MachineCheck ; 0x100, Fatal Machine check (0x20) -VECTOR EV_TLBMissI ; 0x108, Intruction TLB miss (0x21) -VECTOR EV_TLBMissD ; 0x110, Data TLB miss (0x22) -VECTOR EV_TLBProtV ; 0x118, Protection Violation (0x23) - ; or Misaligned Access -VECTOR EV_PrivilegeV ; 0x120, Privilege Violation (0x24) -VECTOR EV_Trap ; 0x128, Trap exception (0x25) -VECTOR EV_Extension ; 0x130, Extn Intruction Excp (0x26) - -.rept 24 -VECTOR reserved ; Reserved Exceptions -.endr - -#include <linux/linkage.h> /* {EXTRY,EXIT} */ -#include <asm/entry.h> /* SAVE_ALL_{INT1,INT2,SYS...} */ -#include <asm/errno.h> -#include <asm/arcregs.h> -#include <asm/irqflags.h> - -;##################### Scratch Mem for IRQ stack switching ############# - -ARCFP_DATA int1_saved_reg - .align 32 - .type int1_saved_reg, @object - .size int1_saved_reg, 4 -int1_saved_reg: - .zero 4 - -/* Each Interrupt level needs its own scratch */ -#ifdef CONFIG_ARC_COMPACT_IRQ_LEVELS - -ARCFP_DATA int2_saved_reg - .type int2_saved_reg, @object - .size int2_saved_reg, 4 -int2_saved_reg: - .zero 4 - -#endif - -; --------------------------------------------- - .section .text, "ax",@progbits - -res_service: ; processor restart - flag 0x1 ; not implemented - nop - nop - -reserved: ; processor restart - rtie ; jump to processor initializations - -;##################### Interrupt Handling ############################## - -#ifdef CONFIG_ARC_COMPACT_IRQ_LEVELS -; --------------------------------------------- -; Level 2 ISR: Can interrupt a Level 1 ISR -; --------------------------------------------- -ENTRY(handle_interrupt_level2) - - INTERRUPT_PROLOGUE 2 - - ;------------------------------------------------------ - ; if L2 IRQ interrupted a L1 ISR, disable preemption - ;------------------------------------------------------ - - ld r9, [sp, PT_status32] ; get statu32_l2 (saved in pt_regs) - bbit0 r9, STATUS_A1_BIT, 1f ; L1 not active when L2 IRQ, so normal - - ; A1 is set in status32_l2 - ; bump thread_info->preempt_count (Disable preemption) - GET_CURR_THR_INFO_FROM_SP r10 - ld r9, [r10, THREAD_INFO_PREEMPT_COUNT] - add r9, r9, 1 - st r9, [r10, THREAD_INFO_PREEMPT_COUNT] - -1: - ;------------------------------------------------------ - ; setup params for Linux common ISR and invoke it - ;------------------------------------------------------ - lr r0, [icause2] - and r0, r0, 0x1f - - bl.d @arch_do_IRQ - mov r1, sp - - mov r8,0x2 - sr r8, [AUX_IRQ_LV12] ; clear bit in Sticky Status Reg - - b ret_from_exception - -END(handle_interrupt_level2) - -#endif - -; --------------------------------------------- -; Level 1 ISR -; --------------------------------------------- -ENTRY(handle_interrupt_level1) - - INTERRUPT_PROLOGUE 1 - - lr r0, [icause1] - and r0, r0, 0x1f - -#ifdef CONFIG_TRACE_IRQFLAGS - ; icause1 needs to be read early, before calling tracing, which - ; can clobber scratch regs, hence use of stack to stash it - push r0 - TRACE_ASM_IRQ_DISABLE - pop r0 -#endif - - bl.d @arch_do_IRQ - mov r1, sp - - mov r8,0x1 - sr r8, [AUX_IRQ_LV12] ; clear bit in Sticky Status Reg - - b ret_from_exception -END(handle_interrupt_level1) - ;################### Non TLB Exception Handling ############################# ; --------------------------------------------- @@ -315,70 +91,6 @@ ENTRY(EV_MachineCheck) END(EV_MachineCheck) ; --------------------------------------------- -; Protection Violation Exception Handler -; --------------------------------------------- - -ENTRY(EV_TLBProtV) - - EXCEPTION_PROLOGUE - - lr r2, [ecr] - lr r0, [efa] ; Faulting Data addr (not part of pt_regs saved above) - - ; Exception auto-disables further Intr/exceptions. - ; Re-enable them by pretending to return from exception - ; (so rest of handler executes in pure K mode) - - FAKE_RET_FROM_EXCPN - - mov r1, sp ; Handle to pt_regs - - ;------ (5) Type of Protection Violation? ---------- - ; - ; ProtV Hardware Exception is triggered for Access Faults of 2 types - ; -Access Violaton : 00_23_(00|01|02|03)_00 - ; x r w r+w - ; -Unaligned Access : 00_23_04_00 - ; - bbit1 r2, ECR_C_BIT_PROTV_MISALIG_DATA, 4f - - ;========= (6a) Access Violation Processing ======== - bl do_page_fault - b ret_from_exception - - ;========== (6b) Non aligned access ============ -4: - - SAVE_CALLEE_SAVED_USER - mov r2, sp ; callee_regs - - bl do_misaligned_access - - ; TBD: optimize - do this only if a callee reg was involved - ; either a dst of emulated LD/ST or src with address-writeback - RESTORE_CALLEE_SAVED_USER - - b ret_from_exception - -END(EV_TLBProtV) - -; Wrapper for Linux page fault handler called from EV_TLBMiss* -; Very similar to ProtV handler case (6a) above, but avoids the extra checks -; for Misaligned access -; -ENTRY(call_do_page_fault) - - EXCEPTION_PROLOGUE - lr r0, [efa] ; Faulting Data address - mov r1, sp - FAKE_RET_FROM_EXCPN - - mov blink, ret_from_exception - b do_page_fault - -END(call_do_page_fault) - -; --------------------------------------------- ; Privilege Violation Exception Handler ; --------------------------------------------- ENTRY(EV_PrivilegeV) @@ -625,97 +337,7 @@ resume_kernel_mode: ; preempt_schedule_irq() always returns with IRQ disabled #endif - ; fall through - -;############# Return from Intr/Excp/Trap (ARC Specifics) ############## -; -; Restore the saved sys context (common exit-path for EXCPN/IRQ/Trap) -; IRQ shd definitely not happen between now and rtie -; All 2 entry points to here already disable interrupts - -.Lrestore_regs: - - TRACE_ASM_IRQ_ENABLE - - lr r10, [status32] - - ; Restore REG File. In case multiple Events outstanding, - ; use the same priorty as rtie: EXCPN, L2 IRQ, L1 IRQ, None - ; Note that we use realtime STATUS32 (not pt_regs->status32) to - ; decide that. - - ; if Returning from Exception - bbit0 r10, STATUS_AE_BIT, not_exception - EXCEPTION_EPILOGUE - rtie - - ; Not Exception so maybe Interrupts (Level 1 or 2) - -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 an L1 ISR, we'd disabled preemption earlier - ; so that sched doesn't move to new task, causing L1 to be delayed - ; undeterministically. Now that we've achieved that, let's reset - ; things to what they were, before returning from L2 context - ;---------------------------------------------------------------- - - 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 - - ; 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 because we would have incremented it. - ; If this does happen we simply HALT as it means a BUG !!! - cmp r9, 0 - bnz 2f - flag 1 - -2: - sub r9, r9, 1 - st r9, [r10, THREAD_INFO_PREEMPT_COUNT] - -149: - ;return from level 2 - INTERRUPT_EPILOGUE 2 -debug_marker_l2: - rtie - -not_level2_interrupt: - -#endif - - bbit0 r10, STATUS_A1_BIT, not_level1_interrupt - - ;return from level 1 - INTERRUPT_EPILOGUE 1 -debug_marker_l1: - rtie - -not_level1_interrupt: - - ;this case is for syscalls or Exceptions (with fake rtie) - - EXCEPTION_EPILOGUE -debug_marker_syscall: - rtie - + b .Lrestore_regs END(ret_from_exception) ENTRY(ret_from_fork) @@ -762,4 +384,7 @@ END(sys_clone_wrapper) ; This also fixes STAR 9000487933 where the prev-workaround (objcopy --setflag) ; would not work after a clean build due to kernel build system dependencies. .section .debug_frame, "wa",@progbits + +; Reset to .text as this file is included in entry-<isa>.S +.section .text, "ax",@progbits #endif |