 41195d236e
			
		
	
	
	41195d236e
	
	
	
		
			
			ARC common code to enable a SMP system + ISS provided SMP extensions. ARC700 natively lacks SMP support, hence some of the core features are are only enabled if SoCs have the necessary h/w pixie-dust. This includes: -Inter Processor Interrupts (IPI) -Cache coherency -load-locked/store-conditional ... The low level exception handling would be completely broken in SMP because we don't have hardware assisted stack switching. Thus a fair bit of this code is repurposing the MMU_SCRATCH reg for event handler prologues to keep them re-entrant. Many thanks to Rajeshwar Ranga for his initial "major" contributions to SMP Port (back in 2008), and to Noam Camus and Gilad Ben-Yossef for help with resurrecting that in 3.2 kernel (2012). Note that this platform code is again singleton design pattern - so multiple SMP platforms won't build at the moment - this deficiency is addressed in subsequent patches within this series. Signed-off-by: Vineet Gupta <vgupta@synopsys.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Rajeshwar Ranga <rajeshwar.ranga@gmail.com> Cc: Noam Camus <noamc@ezchip.com> Cc: Gilad Ben-Yossef <gilad@benyossef.com>
		
			
				
	
	
		
			724 lines
		
	
	
	
		
			20 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			724 lines
		
	
	
	
		
			20 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
| /*
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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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| 
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| #ifndef __ASM_ARC_ENTRY_H
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| #define __ASM_ARC_ENTRY_H
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| 
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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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| 
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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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|  *
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|  * LD.a    reg1, [reg2, x]  => Pre Incr
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|  *      Eff Addr for load = [reg2 + x]
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|  *
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|  * LD.ab   reg1, [reg2, x]  => Post Incr
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|  *      Eff Addr for load = [reg2]
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|  */
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| 
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| /*--------------------------------------------------------------
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|  * Save caller saved registers (scratch registers) ( r0 - r12 )
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|  * Registers are pushed / popped in the order defined in struct ptregs
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|  * in asm/ptrace.h
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|  *-------------------------------------------------------------*/
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| .macro  SAVE_CALLER_SAVED
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| 	st.a    r0, [sp, -4]
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| 	st.a    r1, [sp, -4]
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| 	st.a    r2, [sp, -4]
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| 	st.a    r3, [sp, -4]
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| 	st.a    r4, [sp, -4]
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| 	st.a    r5, [sp, -4]
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| 	st.a    r6, [sp, -4]
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| 	st.a    r7, [sp, -4]
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| 	st.a    r8, [sp, -4]
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| 	st.a    r9, [sp, -4]
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| 	st.a    r10, [sp, -4]
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| 	st.a    r11, [sp, -4]
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| 	st.a    r12, [sp, -4]
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| .endm
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| 
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| /*--------------------------------------------------------------
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|  * Restore caller saved registers (scratch registers)
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|  *-------------------------------------------------------------*/
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| .macro RESTORE_CALLER_SAVED
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| 	ld.ab   r12, [sp, 4]
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| 	ld.ab   r11, [sp, 4]
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| 	ld.ab   r10, [sp, 4]
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| 	ld.ab   r9, [sp, 4]
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| 	ld.ab   r8, [sp, 4]
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| 	ld.ab   r7, [sp, 4]
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| 	ld.ab   r6, [sp, 4]
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| 	ld.ab   r5, [sp, 4]
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| 	ld.ab   r4, [sp, 4]
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| 	ld.ab   r3, [sp, 4]
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| 	ld.ab   r2, [sp, 4]
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| 	ld.ab   r1, [sp, 4]
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| 	ld.ab   r0, [sp, 4]
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| .endm
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| 
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| 
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| /*--------------------------------------------------------------
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|  * Save callee saved registers (non scratch registers) ( r13 - r25 )
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|  *  on kernel stack.
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|  * User mode callee regs need to be saved in case of
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|  *    -fork and friends for replicating from parent to child
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|  *    -before going into do_signal( ) for ptrace/core-dump
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|  * Special case handling is required for r25 in case it is used by kernel
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|  *  for caching task ptr. Low level exception/ISR save user mode r25
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|  *  into task->thread.user_r25. So it needs to be retrieved from there and
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|  *  saved into kernel stack with rest of callee reg-file
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|  *-------------------------------------------------------------*/
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| .macro SAVE_CALLEE_SAVED_USER
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| 	st.a    r13, [sp, -4]
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| 	st.a    r14, [sp, -4]
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| 	st.a    r15, [sp, -4]
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| 	st.a    r16, [sp, -4]
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| 	st.a    r17, [sp, -4]
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| 	st.a    r18, [sp, -4]
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| 	st.a    r19, [sp, -4]
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| 	st.a    r20, [sp, -4]
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| 	st.a    r21, [sp, -4]
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| 	st.a    r22, [sp, -4]
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| 	st.a    r23, [sp, -4]
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| 	st.a    r24, [sp, -4]
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| 
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| #ifdef CONFIG_ARC_CURR_IN_REG
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| 	; Retrieve orig r25 and save it on stack
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| 	ld      r12, [r25, TASK_THREAD + THREAD_USER_R25]
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| 	st.a    r12, [sp, -4]
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| #else
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| 	st.a    r25, [sp, -4]
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| #endif
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| 
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| 	/* move up by 1 word to "create" callee_regs->"stack_place_holder" */
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| 	sub sp, sp, 4
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| .endm
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| 
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| /*--------------------------------------------------------------
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|  * Save callee saved registers (non scratch registers) ( r13 - r25 )
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|  * kernel mode callee regs needed to be saved in case of context switch
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|  * If r25 is used for caching task pointer then that need not be saved
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|  * as it can be re-created from current task global
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|  *-------------------------------------------------------------*/
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| .macro SAVE_CALLEE_SAVED_KERNEL
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| 	st.a    r13, [sp, -4]
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| 	st.a    r14, [sp, -4]
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| 	st.a    r15, [sp, -4]
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| 	st.a    r16, [sp, -4]
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| 	st.a    r17, [sp, -4]
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| 	st.a    r18, [sp, -4]
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| 	st.a    r19, [sp, -4]
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| 	st.a    r20, [sp, -4]
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| 	st.a    r21, [sp, -4]
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| 	st.a    r22, [sp, -4]
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| 	st.a    r23, [sp, -4]
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| 	st.a    r24, [sp, -4]
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| #ifdef CONFIG_ARC_CURR_IN_REG
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| 	sub     sp, sp, 8
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| #else
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| 	st.a    r25, [sp, -4]
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| 	sub     sp, sp, 4
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| #endif
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| .endm
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| 
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| /*--------------------------------------------------------------
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|  * RESTORE_CALLEE_SAVED_KERNEL:
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|  * Loads callee (non scratch) Reg File by popping from Kernel mode stack.
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|  *  This is reverse of SAVE_CALLEE_SAVED,
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|  *
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|  * NOTE:
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|  * Ideally this shd only be called in switch_to for loading
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|  *  switched-IN task's CALLEE Reg File.
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|  *  For all other cases RESTORE_CALLEE_SAVED_FAST must be used
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|  *  which simply pops the stack w/o touching regs.
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|  *-------------------------------------------------------------*/
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| .macro RESTORE_CALLEE_SAVED_KERNEL
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| 
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| 
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| #ifdef CONFIG_ARC_CURR_IN_REG
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| 	add     sp, sp, 8  /* skip callee_reg gutter and user r25 placeholder */
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| #else
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| 	add     sp, sp, 4   /* skip "callee_regs->stack_place_holder" */
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| 	ld.ab   r25, [sp, 4]
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| #endif
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| 
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| 	ld.ab   r24, [sp, 4]
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| 	ld.ab   r23, [sp, 4]
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| 	ld.ab   r22, [sp, 4]
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| 	ld.ab   r21, [sp, 4]
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| 	ld.ab   r20, [sp, 4]
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| 	ld.ab   r19, [sp, 4]
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| 	ld.ab   r18, [sp, 4]
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| 	ld.ab   r17, [sp, 4]
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| 	ld.ab   r16, [sp, 4]
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| 	ld.ab   r15, [sp, 4]
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| 	ld.ab   r14, [sp, 4]
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| 	ld.ab   r13, [sp, 4]
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| 
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| .endm
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| 
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| /*--------------------------------------------------------------
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|  * RESTORE_CALLEE_SAVED_USER:
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|  * This is called after do_signal where tracer might have changed callee regs
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|  * thus we need to restore the reg file.
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|  * Special case handling is required for r25 in case it is used by kernel
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|  *  for caching task ptr. Ptrace would have modified on-kernel-stack value of
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|  *  r25, which needs to be shoved back into task->thread.user_r25 where from
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|  *  Low level exception/ISR return code will retrieve to populate with rest of
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|  *  callee reg-file.
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|  *-------------------------------------------------------------*/
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| .macro RESTORE_CALLEE_SAVED_USER
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| 
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| 	add     sp, sp, 4   /* skip "callee_regs->stack_place_holder" */
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| 
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| #ifdef CONFIG_ARC_CURR_IN_REG
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| 	ld.ab   r12, [sp, 4]
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| 	st      r12, [r25, TASK_THREAD + THREAD_USER_R25]
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| #else
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| 	ld.ab   r25, [sp, 4]
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| #endif
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| 
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| 	ld.ab   r24, [sp, 4]
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| 	ld.ab   r23, [sp, 4]
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| 	ld.ab   r22, [sp, 4]
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| 	ld.ab   r21, [sp, 4]
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| 	ld.ab   r20, [sp, 4]
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| 	ld.ab   r19, [sp, 4]
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| 	ld.ab   r18, [sp, 4]
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| 	ld.ab   r17, [sp, 4]
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| 	ld.ab   r16, [sp, 4]
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| 	ld.ab   r15, [sp, 4]
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| 	ld.ab   r14, [sp, 4]
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| 	ld.ab   r13, [sp, 4]
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| .endm
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| 
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| /*--------------------------------------------------------------
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|  * Super FAST Restore callee saved regs by simply re-adjusting SP
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|  *-------------------------------------------------------------*/
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| .macro DISCARD_CALLEE_SAVED_USER
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| 	add     sp, sp, 14 * 4
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| .endm
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| 
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| /*--------------------------------------------------------------
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|  * Restore User mode r25 saved in task_struct->thread.user_r25
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|  *-------------------------------------------------------------*/
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| .macro RESTORE_USER_R25
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| 	ld  r25, [r25, TASK_THREAD + THREAD_USER_R25]
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| .endm
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| 
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| /*-------------------------------------------------------------
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|  * given a tsk struct, get to the base of it's kernel mode stack
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|  * tsk->thread_info is really a PAGE, whose bottom hoists stack
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|  * which grows upwards towards thread_info
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|  *------------------------------------------------------------*/
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| 
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| .macro GET_TSK_STACK_BASE tsk, out
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| 
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| 	/* Get task->thread_info (this is essentially start of a PAGE) */
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| 	ld  \out, [\tsk, TASK_THREAD_INFO]
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| 
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| 	/* Go to end of page where stack begins (grows upwards) */
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| 	add2 \out, \out, (THREAD_SIZE - 4)/4   /* one word GUTTER */
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| 
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| .endm
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| 
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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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| 
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| .macro SWITCH_TO_KERNEL_STK
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| 
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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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| 
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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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| 
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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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| 
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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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| 
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| #endif
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| 
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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	77f
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| 
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| 	st.a	sp, [sp, -12]	; Make room for orig_r0 and orig_r8
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| 
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| 88: /*------Intr/Ecxp happened in user mode, "switch" stack ------ */
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| 
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| 	GET_CURR_TASK_ON_CPU   r9
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| 
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| #ifdef CONFIG_ARC_CURR_IN_REG
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| 
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| 	/* If current task pointer cached in r25, time to
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| 	 *  -safekeep USER r25 in task->thread_struct->user_r25
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| 	 *  -load r25 with current task ptr
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| 	 */
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| 	st.as	r25, [r9, (TASK_THREAD + THREAD_USER_R25)/4]
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| 	mov	r25, r9
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| #endif
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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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| 
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| #ifdef PT_REGS_CANARY
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| 	st	0xabcdabcd, [r9, 0]
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| #endif
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| 
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| 	/* Save Pre Intr/Exception User SP on kernel stack */
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| 	st.a    sp, [r9, -12]	; Make room for orig_r0 and orig_r8
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| 
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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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| 
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| 	/* set SP to point to kernel mode stack */
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| 	mov sp, r9
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| 
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| 77: /* ----- Stack Switched to kernel Mode, Now save REG FILE ----- */
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| 
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| .endm
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| 
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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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| 
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| .macro FAKE_RET_FROM_EXCPN  reg
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| 
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| 	ld  \reg, [sp, PT_status32]
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| 	bic  \reg, \reg, (STATUS_U_MASK|STATUS_DE_MASK)
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| 	bset \reg, \reg, STATUS_L_BIT
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| 	sr  \reg, [erstatus]
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| 	mov \reg, 55f
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| 	sr  \reg, [eret]
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| 
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| 	rtie
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| 55:
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| .endm
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| 
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| /*
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|  * @reg [OUT] &thread_info of "current"
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|  */
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| .macro GET_CURR_THR_INFO_FROM_SP  reg
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| 	and \reg, sp, ~(THREAD_SIZE - 1)
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| .endm
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| 
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| /*
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|  * @reg [OUT] thread_info->flags of "current"
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|  */
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| .macro GET_CURR_THR_INFO_FLAGS  reg
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| 	GET_CURR_THR_INFO_FROM_SP  \reg
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| 	ld  \reg, [\reg, THREAD_INFO_FLAGS]
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| .endm
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| 
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| /*--------------------------------------------------------------
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|  * For early Exception 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 ptregs.
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|  *-------------------------------------------------------------*/
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| .macro EXCPN_PROLOG_FREEUP_REG	reg
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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, [@ex_saved_reg1]
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| #endif
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| .endm
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| 
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| .macro EXCPN_PROLOG_RESTORE_REG	reg
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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, [@ex_saved_reg1]
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| #endif
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| .endm
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| 
 | |
| /*--------------------------------------------------------------
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|  * Save all registers used by Exceptions (TLB Miss, Prot-V, Mem err etc)
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|  * Requires SP to be already switched to kernel mode Stack
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|  * sp points to the next free element on the stack at exit of this macro.
 | |
|  * Registers are pushed / popped in the order defined in struct ptregs
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|  * in asm/ptrace.h
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|  * Note that syscalls are implemented via TRAP which is also a exception
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|  * from CPU's point of view
 | |
|  *-------------------------------------------------------------*/
 | |
| .macro SAVE_ALL_EXCEPTION   marker
 | |
| 
 | |
| 	st      \marker, [sp, 8]
 | |
| 	st      r0, [sp, 4]    /* orig_r0, needed only for sys calls */
 | |
| 
 | |
| 	/* Restore r9 used to code the early prologue */
 | |
| 	EXCPN_PROLOG_RESTORE_REG  r9
 | |
| 
 | |
| 	SAVE_CALLER_SAVED
 | |
| 	st.a    r26, [sp, -4]   /* gp */
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| 	st.a    fp, [sp, -4]
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| 	st.a    blink, [sp, -4]
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| 	lr	r9, [eret]
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| 	st.a    r9, [sp, -4]
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| 	lr	r9, [erstatus]
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| 	st.a    r9, [sp, -4]
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| 	st.a    lp_count, [sp, -4]
 | |
| 	lr	r9, [lp_end]
 | |
| 	st.a    r9, [sp, -4]
 | |
| 	lr	r9, [lp_start]
 | |
| 	st.a    r9, [sp, -4]
 | |
| 	lr	r9, [erbta]
 | |
| 	st.a    r9, [sp, -4]
 | |
| 
 | |
| #ifdef PT_REGS_CANARY
 | |
| 	mov   r9, 0xdeadbeef
 | |
| 	st    r9, [sp, -4]
 | |
| #endif
 | |
| 
 | |
| 	/* move up by 1 word to "create" pt_regs->"stack_place_holder" */
 | |
| 	sub sp, sp, 4
 | |
| .endm
 | |
| 
 | |
| /*--------------------------------------------------------------
 | |
|  * Save scratch regs for exceptions
 | |
|  *-------------------------------------------------------------*/
 | |
| .macro SAVE_ALL_SYS
 | |
| 	SAVE_ALL_EXCEPTION  orig_r8_IS_EXCPN
 | |
| .endm
 | |
| 
 | |
| /*--------------------------------------------------------------
 | |
|  * Save scratch regs for sys calls
 | |
|  *-------------------------------------------------------------*/
 | |
| .macro SAVE_ALL_TRAP
 | |
| 	/*
 | |
| 	 * Setup pt_regs->orig_r8.
 | |
| 	 * Encode syscall number (r8) in upper short word of event type (r9)
 | |
| 	 * N.B. #1: This is already endian safe (see ptrace.h)
 | |
| 	 *      #2: Only r9 can be used as scratch as it is already clobbered
 | |
| 	 *          and it's contents are no longer needed by the latter part
 | |
| 	 *          of exception prologue
 | |
| 	 */
 | |
| 	lsl  r9, r8, 16
 | |
| 	or   r9, r9, orig_r8_IS_SCALL
 | |
| 
 | |
| 	SAVE_ALL_EXCEPTION  r9
 | |
| .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 RESTORE_ALL_SYS
 | |
| 
 | |
| 	add sp, sp, 4       /* hop over unused "pt_regs->stack_place_holder" */
 | |
| 
 | |
| 	ld.ab   r9, [sp, 4]
 | |
| 	sr	r9, [erbta]
 | |
| 	ld.ab   r9, [sp, 4]
 | |
| 	sr	r9, [lp_start]
 | |
| 	ld.ab   r9, [sp, 4]
 | |
| 	sr	r9, [lp_end]
 | |
| 	ld.ab   r9, [sp, 4]
 | |
| 	mov	lp_count, r9
 | |
| 	ld.ab   r9, [sp, 4]
 | |
| 	sr	r9, [erstatus]
 | |
| 	ld.ab   r9, [sp, 4]
 | |
| 	sr	r9, [eret]
 | |
| 	ld.ab   blink, [sp, 4]
 | |
| 	ld.ab   fp, [sp, 4]
 | |
| 	ld.ab   r26, [sp, 4]    /* gp */
 | |
| 	RESTORE_CALLER_SAVED
 | |
| 
 | |
| 	ld  sp, [sp] /* restore original sp */
 | |
| 	/* orig_r0 and orig_r8 skipped automatically */
 | |
| .endm
 | |
| 
 | |
| 
 | |
| /*--------------------------------------------------------------
 | |
|  * Save all registers used by interrupt handlers.
 | |
|  *-------------------------------------------------------------*/
 | |
| .macro SAVE_ALL_INT1
 | |
| 
 | |
| 	/* restore original r9 , saved in int1_saved_reg
 | |
| 	* It will be saved on stack in macro: SAVE_CALLER_SAVED
 | |
| 	*/
 | |
| #ifdef CONFIG_SMP
 | |
| 	lr  r9, [ARC_REG_SCRATCH_DATA0]
 | |
| #else
 | |
| 	ld  r9, [@int1_saved_reg]
 | |
| #endif
 | |
| 
 | |
| 	/* now we are ready to save the remaining context :) */
 | |
| 	st      orig_r8_IS_IRQ1, [sp, 8]    /* Event Type */
 | |
| 	st      0, [sp, 4]    /* orig_r0 , N/A for IRQ */
 | |
| 	SAVE_CALLER_SAVED
 | |
| 	st.a    r26, [sp, -4]   /* gp */
 | |
| 	st.a    fp, [sp, -4]
 | |
| 	st.a    blink, [sp, -4]
 | |
| 	st.a    ilink1, [sp, -4]
 | |
| 	lr	r9, [status32_l1]
 | |
| 	st.a    r9, [sp, -4]
 | |
| 	st.a    lp_count, [sp, -4]
 | |
| 	lr	r9, [lp_end]
 | |
| 	st.a    r9, [sp, -4]
 | |
| 	lr	r9, [lp_start]
 | |
| 	st.a    r9, [sp, -4]
 | |
| 	lr	r9, [bta_l1]
 | |
| 	st.a    r9, [sp, -4]
 | |
| 
 | |
| #ifdef PT_REGS_CANARY
 | |
| 	mov   r9, 0xdeadbee1
 | |
| 	st    r9, [sp, -4]
 | |
| #endif
 | |
| 	/* move up by 1 word to "create" pt_regs->"stack_place_holder" */
 | |
| 	sub sp, sp, 4
 | |
| .endm
 | |
| 
 | |
| .macro SAVE_ALL_INT2
 | |
| 
 | |
| 	/* TODO-vineetg: SMP we can't use global nor can we use
 | |
| 	*   SCRATCH0 as we do for int1 because while int1 is using
 | |
| 	*   it, int2 can come
 | |
| 	*/
 | |
| 	/* retsore original r9 , saved in sys_saved_r9 */
 | |
| 	ld  r9, [@int2_saved_reg]
 | |
| 
 | |
| 	/* now we are ready to save the remaining context :) */
 | |
| 	st      orig_r8_IS_IRQ2, [sp, 8]    /* Event Type */
 | |
| 	st      0, [sp, 4]    /* orig_r0 , N/A for IRQ */
 | |
| 	SAVE_CALLER_SAVED
 | |
| 	st.a    r26, [sp, -4]   /* gp */
 | |
| 	st.a    fp, [sp, -4]
 | |
| 	st.a    blink, [sp, -4]
 | |
| 	st.a    ilink2, [sp, -4]
 | |
| 	lr	r9, [status32_l2]
 | |
| 	st.a    r9, [sp, -4]
 | |
| 	st.a    lp_count, [sp, -4]
 | |
| 	lr	r9, [lp_end]
 | |
| 	st.a    r9, [sp, -4]
 | |
| 	lr	r9, [lp_start]
 | |
| 	st.a    r9, [sp, -4]
 | |
| 	lr	r9, [bta_l2]
 | |
| 	st.a    r9, [sp, -4]
 | |
| 
 | |
| #ifdef PT_REGS_CANARY
 | |
| 	mov   r9, 0xdeadbee2
 | |
| 	st    r9, [sp, -4]
 | |
| #endif
 | |
| 
 | |
| 	/* move up by 1 word to "create" pt_regs->"stack_place_holder" */
 | |
| 	sub sp, sp, 4
 | |
| .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 RESTORE_ALL_INT1
 | |
| 	add sp, sp, 4       /* hop over unused "pt_regs->stack_place_holder" */
 | |
| 
 | |
| 	ld.ab   r9, [sp, 4] /* Actual reg file */
 | |
| 	sr	r9, [bta_l1]
 | |
| 	ld.ab   r9, [sp, 4]
 | |
| 	sr	r9, [lp_start]
 | |
| 	ld.ab   r9, [sp, 4]
 | |
| 	sr	r9, [lp_end]
 | |
| 	ld.ab   r9, [sp, 4]
 | |
| 	mov	lp_count, r9
 | |
| 	ld.ab   r9, [sp, 4]
 | |
| 	sr	r9, [status32_l1]
 | |
| 	ld.ab   r9, [sp, 4]
 | |
| 	mov	ilink1, r9
 | |
| 	ld.ab   blink, [sp, 4]
 | |
| 	ld.ab   fp, [sp, 4]
 | |
| 	ld.ab   r26, [sp, 4]    /* gp */
 | |
| 	RESTORE_CALLER_SAVED
 | |
| 
 | |
| 	ld  sp, [sp] /* restore original sp */
 | |
| 	/* orig_r0 and orig_r8 skipped automatically */
 | |
| .endm
 | |
| 
 | |
| .macro RESTORE_ALL_INT2
 | |
| 	add sp, sp, 4       /* hop over unused "pt_regs->stack_place_holder" */
 | |
| 
 | |
| 	ld.ab   r9, [sp, 4]
 | |
| 	sr	r9, [bta_l2]
 | |
| 	ld.ab   r9, [sp, 4]
 | |
| 	sr	r9, [lp_start]
 | |
| 	ld.ab   r9, [sp, 4]
 | |
| 	sr	r9, [lp_end]
 | |
| 	ld.ab   r9, [sp, 4]
 | |
| 	mov	lp_count, r9
 | |
| 	ld.ab   r9, [sp, 4]
 | |
| 	sr	r9, [status32_l2]
 | |
| 	ld.ab   r9, [sp, 4]
 | |
| 	mov	ilink2, r9
 | |
| 	ld.ab   blink, [sp, 4]
 | |
| 	ld.ab   fp, [sp, 4]
 | |
| 	ld.ab   r26, [sp, 4]    /* gp */
 | |
| 	RESTORE_CALLER_SAVED
 | |
| 
 | |
| 	ld  sp, [sp] /* restore original sp */
 | |
| 	/* orig_r0 and orig_r8 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
 | |
| 
 | |
| /*-------------------------------------------------
 | |
|  * Retrieve the current running task on this CPU
 | |
|  * 1. Determine curr CPU id.
 | |
|  * 2. Use it to index into _current_task[ ]
 | |
|  */
 | |
| .macro  GET_CURR_TASK_ON_CPU   reg
 | |
| 	GET_CPU_ID  \reg
 | |
| 	ld.as  \reg, [@_current_task, \reg]
 | |
| .endm
 | |
| 
 | |
| /*-------------------------------------------------
 | |
|  * Save a new task as the "current" task on this CPU
 | |
|  * 1. Determine curr CPU id.
 | |
|  * 2. Use it to index into _current_task[ ]
 | |
|  *
 | |
|  * Coded differently than GET_CURR_TASK_ON_CPU (which uses LD.AS)
 | |
|  * because ST r0, [r1, offset] can ONLY have s9 @offset
 | |
|  * while   LD can take s9 (4 byte insn) or LIMM (8 byte insn)
 | |
|  */
 | |
| 
 | |
| .macro  SET_CURR_TASK_ON_CPU    tsk, tmp
 | |
| 	GET_CPU_ID  \tmp
 | |
| 	add2 \tmp, @_current_task, \tmp
 | |
| 	st   \tsk, [\tmp]
 | |
| #ifdef CONFIG_ARC_CURR_IN_REG
 | |
| 	mov r25, \tsk
 | |
| #endif
 | |
| 
 | |
| .endm
 | |
| 
 | |
| 
 | |
| #else   /* Uniprocessor implementation of macros */
 | |
| 
 | |
| .macro  GET_CURR_TASK_ON_CPU    reg
 | |
| 	ld  \reg, [@_current_task]
 | |
| .endm
 | |
| 
 | |
| .macro  SET_CURR_TASK_ON_CPU    tsk, tmp
 | |
| 	st  \tsk, [@_current_task]
 | |
| #ifdef CONFIG_ARC_CURR_IN_REG
 | |
| 	mov r25, \tsk
 | |
| #endif
 | |
| .endm
 | |
| 
 | |
| #endif /* SMP / UNI */
 | |
| 
 | |
| /* ------------------------------------------------------------------
 | |
|  * Get the ptr to some field of Current Task at @off in task struct
 | |
|  *  -Uses r25 for Current task ptr if that is enabled
 | |
|  */
 | |
| 
 | |
| #ifdef CONFIG_ARC_CURR_IN_REG
 | |
| 
 | |
| .macro GET_CURR_TASK_FIELD_PTR  off,  reg
 | |
| 	add \reg, r25, \off
 | |
| .endm
 | |
| 
 | |
| #else
 | |
| 
 | |
| .macro GET_CURR_TASK_FIELD_PTR  off,  reg
 | |
| 	GET_CURR_TASK_ON_CPU  \reg
 | |
| 	add \reg, \reg, \off
 | |
| .endm
 | |
| 
 | |
| #endif	/* CONFIG_ARC_CURR_IN_REG */
 | |
| 
 | |
| #endif  /* __ASSEMBLY__ */
 | |
| 
 | |
| #endif  /* __ASM_ARC_ENTRY_H */
 |