ARC: entry.S: split into ARCompact ISA specific, common bits
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
This commit is contained in:
Vineet Gupta
parent
c10d6969b0
commit
6d1a20b1d2
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@ -0,0 +1,306 @@
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/*
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* Copyright (C) 2014-15 Synopsys, Inc. (www.synopsys.com)
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* Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com)
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License version 2 as
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* published by the Free Software Foundation.
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*
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* Vineetg: March 2009 (Supporting 2 levels of Interrupts)
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* Stack switching code can no longer reliably rely on the fact that
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* if we are NOT in user mode, stack is switched to kernel mode.
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* e.g. L2 IRQ interrupted a L1 ISR which had not yet completed
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* it's prologue including stack switching from user mode
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*
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* Vineetg: Aug 28th 2008: Bug #94984
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* -Zero Overhead Loop Context shd be cleared when entering IRQ/EXcp/Trap
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* Normally CPU does this automatically, however when doing FAKE rtie,
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* we also need to explicitly do this. The problem in macros
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* FAKE_RET_FROM_EXCPN and FAKE_RET_FROM_EXCPN_LOCK_IRQ was that this bit
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* was being "CLEARED" rather then "SET". Actually "SET" clears ZOL context
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*
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* Vineetg: May 5th 2008
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* -Modified CALLEE_REG save/restore macros to handle the fact that
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* r25 contains the kernel current task ptr
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* - Defined Stack Switching Macro to be reused in all intr/excp hdlrs
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* - Shaved off 11 instructions from RESTORE_ALL_INT1 by using the
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* address Write back load ld.ab instead of seperate ld/add instn
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*
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* Amit Bhor, Sameer Dhavale: Codito Technologies 2004
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*/
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#ifndef __ASM_ARC_ENTRY_COMPACT_H
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#define __ASM_ARC_ENTRY_COMPACT_H
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#include <asm/asm-offsets.h>
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#include <asm/thread_info.h> /* For THREAD_SIZE */
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/*--------------------------------------------------------------
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* Switch to Kernel Mode stack if SP points to User Mode stack
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*
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* Entry : r9 contains pre-IRQ/exception/trap status32
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* Exit : SP is set to kernel mode stack pointer
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* If CURR_IN_REG, r25 set to "current" task pointer
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* Clobbers: r9
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*-------------------------------------------------------------*/
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.macro SWITCH_TO_KERNEL_STK
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/* User Mode when this happened ? Yes: Proceed to switch stack */
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bbit1 r9, STATUS_U_BIT, 88f
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/* OK we were already in kernel mode when this event happened, thus can
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* assume SP is kernel mode SP. _NO_ need to do any stack switching
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*/
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#ifdef CONFIG_ARC_COMPACT_IRQ_LEVELS
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/* However....
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* If Level 2 Interrupts enabled, we may end up with a corner case:
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* 1. User Task executing
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* 2. L1 IRQ taken, ISR starts (CPU auto-switched to KERNEL mode)
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* 3. But before it could switch SP from USER to KERNEL stack
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* a L2 IRQ "Interrupts" L1
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* Thay way although L2 IRQ happened in Kernel mode, stack is still
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* not switched.
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* To handle this, we may need to switch stack even if in kernel mode
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* provided SP has values in range of USER mode stack ( < 0x7000_0000 )
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*/
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brlo sp, VMALLOC_START, 88f
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/* TODO: vineetg:
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* We need to be a bit more cautious here. What if a kernel bug in
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* L1 ISR, caused SP to go whaco (some small value which looks like
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* USER stk) and then we take L2 ISR.
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* Above brlo alone would treat it as a valid L1-L2 sceanrio
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* instead of shouting alound
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* The only feasible way is to make sure this L2 happened in
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* L1 prelogue ONLY i.e. ilink2 is less than a pre-set marker in
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* L1 ISR before it switches stack
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*/
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#endif
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/* Save Pre Intr/Exception KERNEL MODE SP on kernel stack
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* safe-keeping not really needed, but it keeps the epilogue code
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* (SP restore) simpler/uniform.
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*/
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b.d 66f
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mov r9, sp
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88: /*------Intr/Ecxp happened in user mode, "switch" stack ------ */
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GET_CURR_TASK_ON_CPU r9
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/* With current tsk in r9, get it's kernel mode stack base */
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GET_TSK_STACK_BASE r9, r9
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66:
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#ifdef CONFIG_ARC_CURR_IN_REG
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/*
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* Treat r25 as scratch reg, save it on stack first
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* Load it with current task pointer
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*/
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st r25, [r9, -4]
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GET_CURR_TASK_ON_CPU r25
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#endif
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/* Save Pre Intr/Exception User SP on kernel stack */
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st.a sp, [r9, -16] ; Make room for orig_r0, ECR, user_r25
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/* CAUTION:
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* SP should be set at the very end when we are done with everything
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* In case of 2 levels of interrupt we depend on value of SP to assume
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* that everything else is done (loading r25 etc)
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*/
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/* set SP to point to kernel mode stack */
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mov sp, r9
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/* ----- Stack Switched to kernel Mode, Now save REG FILE ----- */
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.endm
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/*------------------------------------------------------------
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* "FAKE" a rtie to return from CPU Exception context
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* This is to re-enable Exceptions within exception
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* Look at EV_ProtV to see how this is actually used
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*-------------------------------------------------------------*/
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.macro FAKE_RET_FROM_EXCPN
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ld r9, [sp, PT_status32]
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bic r9, r9, (STATUS_U_MASK|STATUS_DE_MASK)
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bset r9, r9, STATUS_L_BIT
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sr r9, [erstatus]
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mov r9, 55f
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sr r9, [eret]
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rtie
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55:
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.endm
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/*--------------------------------------------------------------
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* For early Exception/ISR Prologue, a core reg is temporarily needed to
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* code the rest of prolog (stack switching). This is done by stashing
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* it to memory (non-SMP case) or SCRATCH0 Aux Reg (SMP).
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*
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* Before saving the full regfile - this reg is restored back, only
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* to be saved again on kernel mode stack, as part of pt_regs.
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*-------------------------------------------------------------*/
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.macro PROLOG_FREEUP_REG reg, mem
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#ifdef CONFIG_SMP
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sr \reg, [ARC_REG_SCRATCH_DATA0]
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#else
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st \reg, [\mem]
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#endif
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.endm
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.macro PROLOG_RESTORE_REG reg, mem
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#ifdef CONFIG_SMP
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lr \reg, [ARC_REG_SCRATCH_DATA0]
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#else
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ld \reg, [\mem]
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#endif
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.endm
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/*--------------------------------------------------------------
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* Exception Entry prologue
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* -Switches stack to K mode (if not already)
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* -Saves the register file
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*
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* After this it is safe to call the "C" handlers
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*-------------------------------------------------------------*/
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.macro EXCEPTION_PROLOGUE
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/* Need at least 1 reg to code the early exception prologue */
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PROLOG_FREEUP_REG r9, @ex_saved_reg1
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/* U/K mode at time of exception (stack not switched if already K) */
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lr r9, [erstatus]
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/* ARC700 doesn't provide auto-stack switching */
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SWITCH_TO_KERNEL_STK
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lr r9, [ecr]
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st r9, [sp, 8] /* ECR */
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st r0, [sp, 4] /* orig_r0, needed only for sys calls */
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/* Restore r9 used to code the early prologue */
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PROLOG_RESTORE_REG r9, @ex_saved_reg1
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SAVE_R0_TO_R12
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PUSH gp
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PUSH fp
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PUSH blink
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PUSHAX eret
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PUSHAX erstatus
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PUSH lp_count
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PUSHAX lp_end
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PUSHAX lp_start
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PUSHAX erbta
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.endm
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/*--------------------------------------------------------------
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* Restore all registers used by system call or Exceptions
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* SP should always be pointing to the next free stack element
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* when entering this macro.
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*
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* NOTE:
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*
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* It is recommended that lp_count/ilink1/ilink2 not be used as a dest reg
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* for memory load operations. If used in that way interrupts are deffered
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* by hardware and that is not good.
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*-------------------------------------------------------------*/
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.macro EXCEPTION_EPILOGUE
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POPAX erbta
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POPAX lp_start
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POPAX lp_end
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POP r9
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mov lp_count, r9 ;LD to lp_count is not allowed
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POPAX erstatus
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POPAX eret
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POP blink
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POP fp
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POP gp
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RESTORE_R12_TO_R0
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ld sp, [sp] /* restore original sp */
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/* orig_r0, ECR, user_r25 skipped automatically */
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.endm
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/* Dummy ECR values for Interrupts */
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#define event_IRQ1 0x0031abcd
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#define event_IRQ2 0x0032abcd
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.macro INTERRUPT_PROLOGUE LVL
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/* free up r9 as scratchpad */
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PROLOG_FREEUP_REG r9, @int\LVL\()_saved_reg
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/* Which mode (user/kernel) was the system in when intr occured */
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lr r9, [status32_l\LVL\()]
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SWITCH_TO_KERNEL_STK
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/* restore original r9 */
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PROLOG_RESTORE_REG r9, @int\LVL\()_saved_reg
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/* now we are ready to save the remaining context */
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st 0x003\LVL\()abcd, [sp, 8] /* Dummy ECR */
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st 0, [sp, 4] /* orig_r0 , N/A for IRQ */
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SAVE_R0_TO_R12
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PUSH gp
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PUSH fp
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PUSH blink
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PUSH ilink\LVL\()
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PUSHAX status32_l\LVL\()
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PUSH lp_count
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PUSHAX lp_end
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PUSHAX lp_start
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PUSHAX bta_l\LVL\()
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.endm
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/*--------------------------------------------------------------
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* Restore all registers used by interrupt handlers.
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*
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* NOTE:
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*
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* It is recommended that lp_count/ilink1/ilink2 not be used as a dest reg
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* for memory load operations. If used in that way interrupts are deffered
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* by hardware and that is not good.
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*-------------------------------------------------------------*/
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.macro INTERRUPT_EPILOGUE LVL
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POPAX bta_l\LVL\()
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POPAX lp_start
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POPAX lp_end
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POP r9
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mov lp_count, r9 ;LD to lp_count is not allowed
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POPAX status32_l\LVL\()
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POP ilink\LVL\()
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POP blink
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POP fp
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POP gp
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RESTORE_R12_TO_R0
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ld sp, [sp] /* restore original sp */
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/* orig_r0, ECR, user_r25 skipped automatically */
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.endm
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/* Get thread_info of "current" tsk */
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.macro GET_CURR_THR_INFO_FROM_SP reg
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bic \reg, sp, (THREAD_SIZE - 1)
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.endm
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/* Get CPU-ID of this core */
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.macro GET_CPU_ID reg
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lr \reg, [identity]
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lsr \reg, \reg, 8
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bmsk \reg, \reg, 7
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.endm
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#endif /* __ASM_ARC_ENTRY_COMPACT_H */
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@ -1,45 +1,23 @@
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/*
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* Copyright (C) 2014-15 Synopsys, Inc. (www.synopsys.com)
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||||
* Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com)
|
||||
*
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||||
* 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)
|
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* Stack switching code can no longer reliably rely on the fact that
|
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* 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
|
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* it's prologue including stack switching from user mode
|
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*
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* Vineetg: Aug 28th 2008: Bug #94984
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* -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
|
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* was being "CLEARED" rather then "SET". Actually "SET" clears ZOL context
|
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*
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* Vineetg: May 5th 2008
|
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* -Modified CALLEE_REG save/restore macros to handle the fact that
|
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* 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
|
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* address Write back load ld.ab instead of seperate ld/add instn
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*
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* Amit Bhor, Sameer Dhavale: Codito Technologies 2004
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*/
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#ifndef __ASM_ARC_ENTRY_H
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#define __ASM_ARC_ENTRY_H
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#ifdef __ASSEMBLY__
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#include <asm/unistd.h> /* For NR_syscalls defination */
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#include <asm/asm-offsets.h>
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#include <asm/arcregs.h>
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#include <asm/ptrace.h>
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#include <asm/processor.h> /* For VMALLOC_START */
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#include <asm/thread_info.h> /* For THREAD_SIZE */
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#include <asm/mmu.h>
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#include <asm/entry-compact.h> /* ISA specific bits */
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/* Note on the LD/ST addr modes with addr reg wback
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*
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* LD.a same as LD.aw
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@ -240,117 +218,6 @@
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.endm
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/*--------------------------------------------------------------
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* Switch to Kernel Mode stack if SP points to User Mode stack
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*
|
||||
* 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
|
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* Clobbers: r9
|
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*-------------------------------------------------------------*/
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.macro SWITCH_TO_KERNEL_STK
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/* User Mode when this happened ? Yes: Proceed to switch stack */
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bbit1 r9, STATUS_U_BIT, 88f
|
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|
||||
/* OK we were already in kernel mode when this event happened, thus can
|
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* 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 )
|
||||
*/
|
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brlo sp, VMALLOC_START, 88f
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|
||||
/* TODO: vineetg:
|
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* We need to be a bit more cautious here. What if a kernel bug in
|
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* L1 ISR, caused SP to go whaco (some small value which looks like
|
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* 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.
|
||||
*/
|
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b.d 66f
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mov r9, sp
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|
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88: /*------Intr/Ecxp happened in user mode, "switch" stack ------ */
|
||||
|
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GET_CURR_TASK_ON_CPU r9
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|
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/* With current tsk in r9, get it's kernel mode stack base */
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GET_TSK_STACK_BASE r9, r9
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66:
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#ifdef CONFIG_ARC_CURR_IN_REG
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/*
|
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* Treat r25 as scratch reg, save it on stack first
|
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* Load it with current task pointer
|
||||
*/
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st r25, [r9, -4]
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GET_CURR_TASK_ON_CPU r25
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#endif
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/* Save Pre Intr/Exception User SP on kernel stack */
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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 */
|
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mov sp, r9
|
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|
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/* ----- 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
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|
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ld r9, [sp, PT_status32]
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bic r9, r9, (STATUS_U_MASK|STATUS_DE_MASK)
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bset r9, r9, STATUS_L_BIT
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sr r9, [erstatus]
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mov r9, 55f
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sr r9, [eret]
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rtie
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55:
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.endm
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/*
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* @reg [OUT] &thread_info of "current"
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||||
*/
|
||||
.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 */
|
||||
|
|
|
|||
|
|
@ -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
|
||||
|
|
|
|||
|
|
@ -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
|
||||
|
|
@ -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 #############################
|
||||
|
||||
; ---------------------------------------------
|
||||
|
|
@ -314,70 +90,6 @@ 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
|
||||
; ---------------------------------------------
|
||||
|
|
@ -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
|
||||
|
|
|
|||
Loading…
Reference in New Issue