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	 e7f75ad01d
			
		
	
	
		e7f75ad01d
		
	
	
	
	
		
			
			This patch adds the base support for the 476 processor. The code was primarily written by Ben Herrenschmidt and Torez Smith, but I've been maintaining it for a while. The goal is to have a single binary that will run on 44x and 47x, but we still have some details to work out. The biggest is that the L1 cache line size differs on the two platforms, but it's currently a compile-time option. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Torez Smith <lnxtorez@linux.vnet.ibm.com> Signed-off-by: Dave Kleikamp <shaggy@linux.vnet.ibm.com> Signed-off-by: Josh Boyer <jwboyer@linux.vnet.ibm.com>
		
			
				
	
	
		
			1383 lines
		
	
	
		
			33 KiB
		
	
	
	
		
			ArmAsm
		
	
	
	
	
	
			
		
		
	
	
			1383 lines
		
	
	
		
			33 KiB
		
	
	
	
		
			ArmAsm
		
	
	
	
	
	
| /*
 | |
|  *  PowerPC version
 | |
|  *    Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
 | |
|  *  Rewritten by Cort Dougan (cort@fsmlabs.com) for PReP
 | |
|  *    Copyright (C) 1996 Cort Dougan <cort@fsmlabs.com>
 | |
|  *  Adapted for Power Macintosh by Paul Mackerras.
 | |
|  *  Low-level exception handlers and MMU support
 | |
|  *  rewritten by Paul Mackerras.
 | |
|  *    Copyright (C) 1996 Paul Mackerras.
 | |
|  *  MPC8xx modifications Copyright (C) 1997 Dan Malek (dmalek@jlc.net).
 | |
|  *
 | |
|  *  This file contains the system call entry code, context switch
 | |
|  *  code, and exception/interrupt return code for PowerPC.
 | |
|  *
 | |
|  *  This program is free software; you can redistribute it and/or
 | |
|  *  modify it under the terms of the GNU General Public License
 | |
|  *  as published by the Free Software Foundation; either version
 | |
|  *  2 of the License, or (at your option) any later version.
 | |
|  *
 | |
|  */
 | |
| 
 | |
| #include <linux/errno.h>
 | |
| #include <linux/sys.h>
 | |
| #include <linux/threads.h>
 | |
| #include <asm/reg.h>
 | |
| #include <asm/page.h>
 | |
| #include <asm/mmu.h>
 | |
| #include <asm/cputable.h>
 | |
| #include <asm/thread_info.h>
 | |
| #include <asm/ppc_asm.h>
 | |
| #include <asm/asm-offsets.h>
 | |
| #include <asm/unistd.h>
 | |
| #include <asm/ftrace.h>
 | |
| 
 | |
| #undef SHOW_SYSCALLS
 | |
| #undef SHOW_SYSCALLS_TASK
 | |
| 
 | |
| /*
 | |
|  * MSR_KERNEL is > 0x10000 on 4xx/Book-E since it include MSR_CE.
 | |
|  */
 | |
| #if MSR_KERNEL >= 0x10000
 | |
| #define LOAD_MSR_KERNEL(r, x)	lis r,(x)@h; ori r,r,(x)@l
 | |
| #else
 | |
| #define LOAD_MSR_KERNEL(r, x)	li r,(x)
 | |
| #endif
 | |
| 
 | |
| #ifdef CONFIG_BOOKE
 | |
| 	.globl	mcheck_transfer_to_handler
 | |
| mcheck_transfer_to_handler:
 | |
| 	mfspr	r0,SPRN_DSRR0
 | |
| 	stw	r0,_DSRR0(r11)
 | |
| 	mfspr	r0,SPRN_DSRR1
 | |
| 	stw	r0,_DSRR1(r11)
 | |
| 	/* fall through */
 | |
| 
 | |
| 	.globl	debug_transfer_to_handler
 | |
| debug_transfer_to_handler:
 | |
| 	mfspr	r0,SPRN_CSRR0
 | |
| 	stw	r0,_CSRR0(r11)
 | |
| 	mfspr	r0,SPRN_CSRR1
 | |
| 	stw	r0,_CSRR1(r11)
 | |
| 	/* fall through */
 | |
| 
 | |
| 	.globl	crit_transfer_to_handler
 | |
| crit_transfer_to_handler:
 | |
| #ifdef CONFIG_PPC_BOOK3E_MMU
 | |
| 	mfspr	r0,SPRN_MAS0
 | |
| 	stw	r0,MAS0(r11)
 | |
| 	mfspr	r0,SPRN_MAS1
 | |
| 	stw	r0,MAS1(r11)
 | |
| 	mfspr	r0,SPRN_MAS2
 | |
| 	stw	r0,MAS2(r11)
 | |
| 	mfspr	r0,SPRN_MAS3
 | |
| 	stw	r0,MAS3(r11)
 | |
| 	mfspr	r0,SPRN_MAS6
 | |
| 	stw	r0,MAS6(r11)
 | |
| #ifdef CONFIG_PHYS_64BIT
 | |
| 	mfspr	r0,SPRN_MAS7
 | |
| 	stw	r0,MAS7(r11)
 | |
| #endif /* CONFIG_PHYS_64BIT */
 | |
| #endif /* CONFIG_PPC_BOOK3E_MMU */
 | |
| #ifdef CONFIG_44x
 | |
| 	mfspr	r0,SPRN_MMUCR
 | |
| 	stw	r0,MMUCR(r11)
 | |
| #endif
 | |
| 	mfspr	r0,SPRN_SRR0
 | |
| 	stw	r0,_SRR0(r11)
 | |
| 	mfspr	r0,SPRN_SRR1
 | |
| 	stw	r0,_SRR1(r11)
 | |
| 
 | |
| 	mfspr	r8,SPRN_SPRG_THREAD
 | |
| 	lwz	r0,KSP_LIMIT(r8)
 | |
| 	stw	r0,SAVED_KSP_LIMIT(r11)
 | |
| 	rlwimi	r0,r1,0,0,(31-THREAD_SHIFT)
 | |
| 	stw	r0,KSP_LIMIT(r8)
 | |
| 	/* fall through */
 | |
| #endif
 | |
| 
 | |
| #ifdef CONFIG_40x
 | |
| 	.globl	crit_transfer_to_handler
 | |
| crit_transfer_to_handler:
 | |
| 	lwz	r0,crit_r10@l(0)
 | |
| 	stw	r0,GPR10(r11)
 | |
| 	lwz	r0,crit_r11@l(0)
 | |
| 	stw	r0,GPR11(r11)
 | |
| 	mfspr	r0,SPRN_SRR0
 | |
| 	stw	r0,crit_srr0@l(0)
 | |
| 	mfspr	r0,SPRN_SRR1
 | |
| 	stw	r0,crit_srr1@l(0)
 | |
| 
 | |
| 	mfspr	r8,SPRN_SPRG_THREAD
 | |
| 	lwz	r0,KSP_LIMIT(r8)
 | |
| 	stw	r0,saved_ksp_limit@l(0)
 | |
| 	rlwimi	r0,r1,0,0,(31-THREAD_SHIFT)
 | |
| 	stw	r0,KSP_LIMIT(r8)
 | |
| 	/* fall through */
 | |
| #endif
 | |
| 
 | |
| /*
 | |
|  * This code finishes saving the registers to the exception frame
 | |
|  * and jumps to the appropriate handler for the exception, turning
 | |
|  * on address translation.
 | |
|  * Note that we rely on the caller having set cr0.eq iff the exception
 | |
|  * occurred in kernel mode (i.e. MSR:PR = 0).
 | |
|  */
 | |
| 	.globl	transfer_to_handler_full
 | |
| transfer_to_handler_full:
 | |
| 	SAVE_NVGPRS(r11)
 | |
| 	/* fall through */
 | |
| 
 | |
| 	.globl	transfer_to_handler
 | |
| transfer_to_handler:
 | |
| 	stw	r2,GPR2(r11)
 | |
| 	stw	r12,_NIP(r11)
 | |
| 	stw	r9,_MSR(r11)
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| 	andi.	r2,r9,MSR_PR
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| 	mfctr	r12
 | |
| 	mfspr	r2,SPRN_XER
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| 	stw	r12,_CTR(r11)
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| 	stw	r2,_XER(r11)
 | |
| 	mfspr	r12,SPRN_SPRG_THREAD
 | |
| 	addi	r2,r12,-THREAD
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| 	tovirt(r2,r2)			/* set r2 to current */
 | |
| 	beq	2f			/* if from user, fix up THREAD.regs */
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| 	addi	r11,r1,STACK_FRAME_OVERHEAD
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| 	stw	r11,PT_REGS(r12)
 | |
| #if defined(CONFIG_40x) || defined(CONFIG_BOOKE)
 | |
| 	/* Check to see if the dbcr0 register is set up to debug.  Use the
 | |
| 	   internal debug mode bit to do this. */
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| 	lwz	r12,THREAD_DBCR0(r12)
 | |
| 	andis.	r12,r12,DBCR0_IDM@h
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| 	beq+	3f
 | |
| 	/* From user and task is ptraced - load up global dbcr0 */
 | |
| 	li	r12,-1			/* clear all pending debug events */
 | |
| 	mtspr	SPRN_DBSR,r12
 | |
| 	lis	r11,global_dbcr0@ha
 | |
| 	tophys(r11,r11)
 | |
| 	addi	r11,r11,global_dbcr0@l
 | |
| #ifdef CONFIG_SMP
 | |
| 	rlwinm	r9,r1,0,0,(31-THREAD_SHIFT)
 | |
| 	lwz	r9,TI_CPU(r9)
 | |
| 	slwi	r9,r9,3
 | |
| 	add	r11,r11,r9
 | |
| #endif
 | |
| 	lwz	r12,0(r11)
 | |
| 	mtspr	SPRN_DBCR0,r12
 | |
| 	lwz	r12,4(r11)
 | |
| 	addi	r12,r12,-1
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| 	stw	r12,4(r11)
 | |
| #endif
 | |
| 	b	3f
 | |
| 
 | |
| 2:	/* if from kernel, check interrupted DOZE/NAP mode and
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|          * check for stack overflow
 | |
|          */
 | |
| 	lwz	r9,KSP_LIMIT(r12)
 | |
| 	cmplw	r1,r9			/* if r1 <= ksp_limit */
 | |
| 	ble-	stack_ovf		/* then the kernel stack overflowed */
 | |
| 5:
 | |
| #if defined(CONFIG_6xx) || defined(CONFIG_E500)
 | |
| 	rlwinm	r9,r1,0,0,31-THREAD_SHIFT
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| 	tophys(r9,r9)			/* check local flags */
 | |
| 	lwz	r12,TI_LOCAL_FLAGS(r9)
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| 	mtcrf	0x01,r12
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| 	bt-	31-TLF_NAPPING,4f
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| 	bt-	31-TLF_SLEEPING,7f
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| #endif /* CONFIG_6xx || CONFIG_E500 */
 | |
| 	.globl transfer_to_handler_cont
 | |
| transfer_to_handler_cont:
 | |
| 3:
 | |
| 	mflr	r9
 | |
| 	lwz	r11,0(r9)		/* virtual address of handler */
 | |
| 	lwz	r9,4(r9)		/* where to go when done */
 | |
| #ifdef CONFIG_TRACE_IRQFLAGS
 | |
| 	lis	r12,reenable_mmu@h
 | |
| 	ori	r12,r12,reenable_mmu@l
 | |
| 	mtspr	SPRN_SRR0,r12
 | |
| 	mtspr	SPRN_SRR1,r10
 | |
| 	SYNC
 | |
| 	RFI
 | |
| reenable_mmu:				/* re-enable mmu so we can */
 | |
| 	mfmsr	r10
 | |
| 	lwz	r12,_MSR(r1)
 | |
| 	xor	r10,r10,r12
 | |
| 	andi.	r10,r10,MSR_EE		/* Did EE change? */
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| 	beq	1f
 | |
| 
 | |
| 	/* Save handler and return address into the 2 unused words
 | |
| 	 * of the STACK_FRAME_OVERHEAD (sneak sneak sneak). Everything
 | |
| 	 * else can be recovered from the pt_regs except r3 which for
 | |
| 	 * normal interrupts has been set to pt_regs and for syscalls
 | |
| 	 * is an argument, so we temporarily use ORIG_GPR3 to save it
 | |
| 	 */
 | |
| 	stw	r9,8(r1)
 | |
| 	stw	r11,12(r1)
 | |
| 	stw	r3,ORIG_GPR3(r1)
 | |
| 	bl	trace_hardirqs_off
 | |
| 	lwz	r0,GPR0(r1)
 | |
| 	lwz	r3,ORIG_GPR3(r1)
 | |
| 	lwz	r4,GPR4(r1)
 | |
| 	lwz	r5,GPR5(r1)
 | |
| 	lwz	r6,GPR6(r1)
 | |
| 	lwz	r7,GPR7(r1)
 | |
| 	lwz	r8,GPR8(r1)
 | |
| 	lwz	r9,8(r1)
 | |
| 	lwz	r11,12(r1)
 | |
| 1:	mtctr	r11
 | |
| 	mtlr	r9
 | |
| 	bctr				/* jump to handler */
 | |
| #else /* CONFIG_TRACE_IRQFLAGS */
 | |
| 	mtspr	SPRN_SRR0,r11
 | |
| 	mtspr	SPRN_SRR1,r10
 | |
| 	mtlr	r9
 | |
| 	SYNC
 | |
| 	RFI				/* jump to handler, enable MMU */
 | |
| #endif /* CONFIG_TRACE_IRQFLAGS */
 | |
| 
 | |
| #if defined (CONFIG_6xx) || defined(CONFIG_E500)
 | |
| 4:	rlwinm	r12,r12,0,~_TLF_NAPPING
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| 	stw	r12,TI_LOCAL_FLAGS(r9)
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| 	b	power_save_ppc32_restore
 | |
| 
 | |
| 7:	rlwinm	r12,r12,0,~_TLF_SLEEPING
 | |
| 	stw	r12,TI_LOCAL_FLAGS(r9)
 | |
| 	lwz	r9,_MSR(r11)		/* if sleeping, clear MSR.EE */
 | |
| 	rlwinm	r9,r9,0,~MSR_EE
 | |
| 	lwz	r12,_LINK(r11)		/* and return to address in LR */
 | |
| 	b	fast_exception_return
 | |
| #endif
 | |
| 
 | |
| /*
 | |
|  * On kernel stack overflow, load up an initial stack pointer
 | |
|  * and call StackOverflow(regs), which should not return.
 | |
|  */
 | |
| stack_ovf:
 | |
| 	/* sometimes we use a statically-allocated stack, which is OK. */
 | |
| 	lis	r12,_end@h
 | |
| 	ori	r12,r12,_end@l
 | |
| 	cmplw	r1,r12
 | |
| 	ble	5b			/* r1 <= &_end is OK */
 | |
| 	SAVE_NVGPRS(r11)
 | |
| 	addi	r3,r1,STACK_FRAME_OVERHEAD
 | |
| 	lis	r1,init_thread_union@ha
 | |
| 	addi	r1,r1,init_thread_union@l
 | |
| 	addi	r1,r1,THREAD_SIZE-STACK_FRAME_OVERHEAD
 | |
| 	lis	r9,StackOverflow@ha
 | |
| 	addi	r9,r9,StackOverflow@l
 | |
| 	LOAD_MSR_KERNEL(r10,MSR_KERNEL)
 | |
| 	FIX_SRR1(r10,r12)
 | |
| 	mtspr	SPRN_SRR0,r9
 | |
| 	mtspr	SPRN_SRR1,r10
 | |
| 	SYNC
 | |
| 	RFI
 | |
| 
 | |
| /*
 | |
|  * Handle a system call.
 | |
|  */
 | |
| 	.stabs	"arch/powerpc/kernel/",N_SO,0,0,0f
 | |
| 	.stabs	"entry_32.S",N_SO,0,0,0f
 | |
| 0:
 | |
| 
 | |
| _GLOBAL(DoSyscall)
 | |
| 	stw	r3,ORIG_GPR3(r1)
 | |
| 	li	r12,0
 | |
| 	stw	r12,RESULT(r1)
 | |
| 	lwz	r11,_CCR(r1)	/* Clear SO bit in CR */
 | |
| 	rlwinm	r11,r11,0,4,2
 | |
| 	stw	r11,_CCR(r1)
 | |
| #ifdef SHOW_SYSCALLS
 | |
| 	bl	do_show_syscall
 | |
| #endif /* SHOW_SYSCALLS */
 | |
| #ifdef CONFIG_TRACE_IRQFLAGS
 | |
| 	/* Return from syscalls can (and generally will) hard enable
 | |
| 	 * interrupts. You aren't supposed to call a syscall with
 | |
| 	 * interrupts disabled in the first place. However, to ensure
 | |
| 	 * that we get it right vs. lockdep if it happens, we force
 | |
| 	 * that hard enable here with appropriate tracing if we see
 | |
| 	 * that we have been called with interrupts off
 | |
| 	 */
 | |
| 	mfmsr	r11
 | |
| 	andi.	r12,r11,MSR_EE
 | |
| 	bne+	1f
 | |
| 	/* We came in with interrupts disabled, we enable them now */
 | |
| 	bl	trace_hardirqs_on
 | |
| 	mfmsr	r11
 | |
| 	lwz	r0,GPR0(r1)
 | |
| 	lwz	r3,GPR3(r1)
 | |
| 	lwz	r4,GPR4(r1)
 | |
| 	ori	r11,r11,MSR_EE
 | |
| 	lwz	r5,GPR5(r1)
 | |
| 	lwz	r6,GPR6(r1)
 | |
| 	lwz	r7,GPR7(r1)
 | |
| 	lwz	r8,GPR8(r1)
 | |
| 	mtmsr	r11
 | |
| 1:
 | |
| #endif /* CONFIG_TRACE_IRQFLAGS */
 | |
| 	rlwinm	r10,r1,0,0,(31-THREAD_SHIFT)	/* current_thread_info() */
 | |
| 	lwz	r11,TI_FLAGS(r10)
 | |
| 	andi.	r11,r11,_TIF_SYSCALL_T_OR_A
 | |
| 	bne-	syscall_dotrace
 | |
| syscall_dotrace_cont:
 | |
| 	cmplwi	0,r0,NR_syscalls
 | |
| 	lis	r10,sys_call_table@h
 | |
| 	ori	r10,r10,sys_call_table@l
 | |
| 	slwi	r0,r0,2
 | |
| 	bge-	66f
 | |
| 	lwzx	r10,r10,r0	/* Fetch system call handler [ptr] */
 | |
| 	mtlr	r10
 | |
| 	addi	r9,r1,STACK_FRAME_OVERHEAD
 | |
| 	PPC440EP_ERR42
 | |
| 	blrl			/* Call handler */
 | |
| 	.globl	ret_from_syscall
 | |
| ret_from_syscall:
 | |
| #ifdef SHOW_SYSCALLS
 | |
| 	bl	do_show_syscall_exit
 | |
| #endif
 | |
| 	mr	r6,r3
 | |
| 	rlwinm	r12,r1,0,0,(31-THREAD_SHIFT)	/* current_thread_info() */
 | |
| 	/* disable interrupts so current_thread_info()->flags can't change */
 | |
| 	LOAD_MSR_KERNEL(r10,MSR_KERNEL)	/* doesn't include MSR_EE */
 | |
| 	/* Note: We don't bother telling lockdep about it */
 | |
| 	SYNC
 | |
| 	MTMSRD(r10)
 | |
| 	lwz	r9,TI_FLAGS(r12)
 | |
| 	li	r8,-_LAST_ERRNO
 | |
| 	andi.	r0,r9,(_TIF_SYSCALL_T_OR_A|_TIF_SINGLESTEP|_TIF_USER_WORK_MASK|_TIF_PERSYSCALL_MASK)
 | |
| 	bne-	syscall_exit_work
 | |
| 	cmplw	0,r3,r8
 | |
| 	blt+	syscall_exit_cont
 | |
| 	lwz	r11,_CCR(r1)			/* Load CR */
 | |
| 	neg	r3,r3
 | |
| 	oris	r11,r11,0x1000	/* Set SO bit in CR */
 | |
| 	stw	r11,_CCR(r1)
 | |
| syscall_exit_cont:
 | |
| 	lwz	r8,_MSR(r1)
 | |
| #ifdef CONFIG_TRACE_IRQFLAGS
 | |
| 	/* If we are going to return from the syscall with interrupts
 | |
| 	 * off, we trace that here. It shouldn't happen though but we
 | |
| 	 * want to catch the bugger if it does right ?
 | |
| 	 */
 | |
| 	andi.	r10,r8,MSR_EE
 | |
| 	bne+	1f
 | |
| 	stw	r3,GPR3(r1)
 | |
| 	bl      trace_hardirqs_off
 | |
| 	lwz	r3,GPR3(r1)
 | |
| 1:
 | |
| #endif /* CONFIG_TRACE_IRQFLAGS */
 | |
| #if defined(CONFIG_4xx) || defined(CONFIG_BOOKE)
 | |
| 	/* If the process has its own DBCR0 value, load it up.  The internal
 | |
| 	   debug mode bit tells us that dbcr0 should be loaded. */
 | |
| 	lwz	r0,THREAD+THREAD_DBCR0(r2)
 | |
| 	andis.	r10,r0,DBCR0_IDM@h
 | |
| 	bnel-	load_dbcr0
 | |
| #endif
 | |
| #ifdef CONFIG_44x
 | |
| BEGIN_MMU_FTR_SECTION
 | |
| 	lis	r4,icache_44x_need_flush@ha
 | |
| 	lwz	r5,icache_44x_need_flush@l(r4)
 | |
| 	cmplwi	cr0,r5,0
 | |
| 	bne-	2f
 | |
| 1:
 | |
| END_MMU_FTR_SECTION_IFCLR(MMU_FTR_TYPE_47x)
 | |
| #endif /* CONFIG_44x */
 | |
| BEGIN_FTR_SECTION
 | |
| 	lwarx	r7,0,r1
 | |
| END_FTR_SECTION_IFSET(CPU_FTR_NEED_PAIRED_STWCX)
 | |
| 	stwcx.	r0,0,r1			/* to clear the reservation */
 | |
| 	lwz	r4,_LINK(r1)
 | |
| 	lwz	r5,_CCR(r1)
 | |
| 	mtlr	r4
 | |
| 	mtcr	r5
 | |
| 	lwz	r7,_NIP(r1)
 | |
| 	FIX_SRR1(r8, r0)
 | |
| 	lwz	r2,GPR2(r1)
 | |
| 	lwz	r1,GPR1(r1)
 | |
| 	mtspr	SPRN_SRR0,r7
 | |
| 	mtspr	SPRN_SRR1,r8
 | |
| 	SYNC
 | |
| 	RFI
 | |
| #ifdef CONFIG_44x
 | |
| 2:	li	r7,0
 | |
| 	iccci	r0,r0
 | |
| 	stw	r7,icache_44x_need_flush@l(r4)
 | |
| 	b	1b
 | |
| #endif  /* CONFIG_44x */
 | |
| 
 | |
| 66:	li	r3,-ENOSYS
 | |
| 	b	ret_from_syscall
 | |
| 
 | |
| 	.globl	ret_from_fork
 | |
| ret_from_fork:
 | |
| 	REST_NVGPRS(r1)
 | |
| 	bl	schedule_tail
 | |
| 	li	r3,0
 | |
| 	b	ret_from_syscall
 | |
| 
 | |
| /* Traced system call support */
 | |
| syscall_dotrace:
 | |
| 	SAVE_NVGPRS(r1)
 | |
| 	li	r0,0xc00
 | |
| 	stw	r0,_TRAP(r1)
 | |
| 	addi	r3,r1,STACK_FRAME_OVERHEAD
 | |
| 	bl	do_syscall_trace_enter
 | |
| 	/*
 | |
| 	 * Restore argument registers possibly just changed.
 | |
| 	 * We use the return value of do_syscall_trace_enter
 | |
| 	 * for call number to look up in the table (r0).
 | |
| 	 */
 | |
| 	mr	r0,r3
 | |
| 	lwz	r3,GPR3(r1)
 | |
| 	lwz	r4,GPR4(r1)
 | |
| 	lwz	r5,GPR5(r1)
 | |
| 	lwz	r6,GPR6(r1)
 | |
| 	lwz	r7,GPR7(r1)
 | |
| 	lwz	r8,GPR8(r1)
 | |
| 	REST_NVGPRS(r1)
 | |
| 	b	syscall_dotrace_cont
 | |
| 
 | |
| syscall_exit_work:
 | |
| 	andi.	r0,r9,_TIF_RESTOREALL
 | |
| 	beq+	0f
 | |
| 	REST_NVGPRS(r1)
 | |
| 	b	2f
 | |
| 0:	cmplw	0,r3,r8
 | |
| 	blt+	1f
 | |
| 	andi.	r0,r9,_TIF_NOERROR
 | |
| 	bne-	1f
 | |
| 	lwz	r11,_CCR(r1)			/* Load CR */
 | |
| 	neg	r3,r3
 | |
| 	oris	r11,r11,0x1000	/* Set SO bit in CR */
 | |
| 	stw	r11,_CCR(r1)
 | |
| 
 | |
| 1:	stw	r6,RESULT(r1)	/* Save result */
 | |
| 	stw	r3,GPR3(r1)	/* Update return value */
 | |
| 2:	andi.	r0,r9,(_TIF_PERSYSCALL_MASK)
 | |
| 	beq	4f
 | |
| 
 | |
| 	/* Clear per-syscall TIF flags if any are set.  */
 | |
| 
 | |
| 	li	r11,_TIF_PERSYSCALL_MASK
 | |
| 	addi	r12,r12,TI_FLAGS
 | |
| 3:	lwarx	r8,0,r12
 | |
| 	andc	r8,r8,r11
 | |
| #ifdef CONFIG_IBM405_ERR77
 | |
| 	dcbt	0,r12
 | |
| #endif
 | |
| 	stwcx.	r8,0,r12
 | |
| 	bne-	3b
 | |
| 	subi	r12,r12,TI_FLAGS
 | |
| 	
 | |
| 4:	/* Anything which requires enabling interrupts? */
 | |
| 	andi.	r0,r9,(_TIF_SYSCALL_T_OR_A|_TIF_SINGLESTEP)
 | |
| 	beq	ret_from_except
 | |
| 
 | |
| 	/* Re-enable interrupts. There is no need to trace that with
 | |
| 	 * lockdep as we are supposed to have IRQs on at this point
 | |
| 	 */
 | |
| 	ori	r10,r10,MSR_EE
 | |
| 	SYNC
 | |
| 	MTMSRD(r10)
 | |
| 
 | |
| 	/* Save NVGPRS if they're not saved already */
 | |
| 	lwz	r4,_TRAP(r1)
 | |
| 	andi.	r4,r4,1
 | |
| 	beq	5f
 | |
| 	SAVE_NVGPRS(r1)
 | |
| 	li	r4,0xc00
 | |
| 	stw	r4,_TRAP(r1)
 | |
| 5:
 | |
| 	addi	r3,r1,STACK_FRAME_OVERHEAD
 | |
| 	bl	do_syscall_trace_leave
 | |
| 	b	ret_from_except_full
 | |
| 
 | |
| #ifdef SHOW_SYSCALLS
 | |
| do_show_syscall:
 | |
| #ifdef SHOW_SYSCALLS_TASK
 | |
| 	lis	r11,show_syscalls_task@ha
 | |
| 	lwz	r11,show_syscalls_task@l(r11)
 | |
| 	cmp	0,r2,r11
 | |
| 	bnelr
 | |
| #endif
 | |
| 	stw	r31,GPR31(r1)
 | |
| 	mflr	r31
 | |
| 	lis	r3,7f@ha
 | |
| 	addi	r3,r3,7f@l
 | |
| 	lwz	r4,GPR0(r1)
 | |
| 	lwz	r5,GPR3(r1)
 | |
| 	lwz	r6,GPR4(r1)
 | |
| 	lwz	r7,GPR5(r1)
 | |
| 	lwz	r8,GPR6(r1)
 | |
| 	lwz	r9,GPR7(r1)
 | |
| 	bl	printk
 | |
| 	lis	r3,77f@ha
 | |
| 	addi	r3,r3,77f@l
 | |
| 	lwz	r4,GPR8(r1)
 | |
| 	mr	r5,r2
 | |
| 	bl	printk
 | |
| 	lwz	r0,GPR0(r1)
 | |
| 	lwz	r3,GPR3(r1)
 | |
| 	lwz	r4,GPR4(r1)
 | |
| 	lwz	r5,GPR5(r1)
 | |
| 	lwz	r6,GPR6(r1)
 | |
| 	lwz	r7,GPR7(r1)
 | |
| 	lwz	r8,GPR8(r1)
 | |
| 	mtlr	r31
 | |
| 	lwz	r31,GPR31(r1)
 | |
| 	blr
 | |
| 
 | |
| do_show_syscall_exit:
 | |
| #ifdef SHOW_SYSCALLS_TASK
 | |
| 	lis	r11,show_syscalls_task@ha
 | |
| 	lwz	r11,show_syscalls_task@l(r11)
 | |
| 	cmp	0,r2,r11
 | |
| 	bnelr
 | |
| #endif
 | |
| 	stw	r31,GPR31(r1)
 | |
| 	mflr	r31
 | |
| 	stw	r3,RESULT(r1)	/* Save result */
 | |
| 	mr	r4,r3
 | |
| 	lis	r3,79f@ha
 | |
| 	addi	r3,r3,79f@l
 | |
| 	bl	printk
 | |
| 	lwz	r3,RESULT(r1)
 | |
| 	mtlr	r31
 | |
| 	lwz	r31,GPR31(r1)
 | |
| 	blr
 | |
| 
 | |
| 7:	.string	"syscall %d(%x, %x, %x, %x, %x, "
 | |
| 77:	.string	"%x), current=%p\n"
 | |
| 79:	.string	" -> %x\n"
 | |
| 	.align	2,0
 | |
| 
 | |
| #ifdef SHOW_SYSCALLS_TASK
 | |
| 	.data
 | |
| 	.globl	show_syscalls_task
 | |
| show_syscalls_task:
 | |
| 	.long	-1
 | |
| 	.text
 | |
| #endif
 | |
| #endif /* SHOW_SYSCALLS */
 | |
| 
 | |
| /*
 | |
|  * The fork/clone functions need to copy the full register set into
 | |
|  * the child process. Therefore we need to save all the nonvolatile
 | |
|  * registers (r13 - r31) before calling the C code.
 | |
|  */
 | |
| 	.globl	ppc_fork
 | |
| ppc_fork:
 | |
| 	SAVE_NVGPRS(r1)
 | |
| 	lwz	r0,_TRAP(r1)
 | |
| 	rlwinm	r0,r0,0,0,30		/* clear LSB to indicate full */
 | |
| 	stw	r0,_TRAP(r1)		/* register set saved */
 | |
| 	b	sys_fork
 | |
| 
 | |
| 	.globl	ppc_vfork
 | |
| ppc_vfork:
 | |
| 	SAVE_NVGPRS(r1)
 | |
| 	lwz	r0,_TRAP(r1)
 | |
| 	rlwinm	r0,r0,0,0,30		/* clear LSB to indicate full */
 | |
| 	stw	r0,_TRAP(r1)		/* register set saved */
 | |
| 	b	sys_vfork
 | |
| 
 | |
| 	.globl	ppc_clone
 | |
| ppc_clone:
 | |
| 	SAVE_NVGPRS(r1)
 | |
| 	lwz	r0,_TRAP(r1)
 | |
| 	rlwinm	r0,r0,0,0,30		/* clear LSB to indicate full */
 | |
| 	stw	r0,_TRAP(r1)		/* register set saved */
 | |
| 	b	sys_clone
 | |
| 
 | |
| 	.globl	ppc_swapcontext
 | |
| ppc_swapcontext:
 | |
| 	SAVE_NVGPRS(r1)
 | |
| 	lwz	r0,_TRAP(r1)
 | |
| 	rlwinm	r0,r0,0,0,30		/* clear LSB to indicate full */
 | |
| 	stw	r0,_TRAP(r1)		/* register set saved */
 | |
| 	b	sys_swapcontext
 | |
| 
 | |
| /*
 | |
|  * Top-level page fault handling.
 | |
|  * This is in assembler because if do_page_fault tells us that
 | |
|  * it is a bad kernel page fault, we want to save the non-volatile
 | |
|  * registers before calling bad_page_fault.
 | |
|  */
 | |
| 	.globl	handle_page_fault
 | |
| handle_page_fault:
 | |
| 	stw	r4,_DAR(r1)
 | |
| 	addi	r3,r1,STACK_FRAME_OVERHEAD
 | |
| 	bl	do_page_fault
 | |
| 	cmpwi	r3,0
 | |
| 	beq+	ret_from_except
 | |
| 	SAVE_NVGPRS(r1)
 | |
| 	lwz	r0,_TRAP(r1)
 | |
| 	clrrwi	r0,r0,1
 | |
| 	stw	r0,_TRAP(r1)
 | |
| 	mr	r5,r3
 | |
| 	addi	r3,r1,STACK_FRAME_OVERHEAD
 | |
| 	lwz	r4,_DAR(r1)
 | |
| 	bl	bad_page_fault
 | |
| 	b	ret_from_except_full
 | |
| 
 | |
| /*
 | |
|  * This routine switches between two different tasks.  The process
 | |
|  * state of one is saved on its kernel stack.  Then the state
 | |
|  * of the other is restored from its kernel stack.  The memory
 | |
|  * management hardware is updated to the second process's state.
 | |
|  * Finally, we can return to the second process.
 | |
|  * On entry, r3 points to the THREAD for the current task, r4
 | |
|  * points to the THREAD for the new task.
 | |
|  *
 | |
|  * This routine is always called with interrupts disabled.
 | |
|  *
 | |
|  * Note: there are two ways to get to the "going out" portion
 | |
|  * of this code; either by coming in via the entry (_switch)
 | |
|  * or via "fork" which must set up an environment equivalent
 | |
|  * to the "_switch" path.  If you change this , you'll have to
 | |
|  * change the fork code also.
 | |
|  *
 | |
|  * The code which creates the new task context is in 'copy_thread'
 | |
|  * in arch/ppc/kernel/process.c
 | |
|  */
 | |
| _GLOBAL(_switch)
 | |
| 	stwu	r1,-INT_FRAME_SIZE(r1)
 | |
| 	mflr	r0
 | |
| 	stw	r0,INT_FRAME_SIZE+4(r1)
 | |
| 	/* r3-r12 are caller saved -- Cort */
 | |
| 	SAVE_NVGPRS(r1)
 | |
| 	stw	r0,_NIP(r1)	/* Return to switch caller */
 | |
| 	mfmsr	r11
 | |
| 	li	r0,MSR_FP	/* Disable floating-point */
 | |
| #ifdef CONFIG_ALTIVEC
 | |
| BEGIN_FTR_SECTION
 | |
| 	oris	r0,r0,MSR_VEC@h	/* Disable altivec */
 | |
| 	mfspr	r12,SPRN_VRSAVE	/* save vrsave register value */
 | |
| 	stw	r12,THREAD+THREAD_VRSAVE(r2)
 | |
| END_FTR_SECTION_IFSET(CPU_FTR_ALTIVEC)
 | |
| #endif /* CONFIG_ALTIVEC */
 | |
| #ifdef CONFIG_SPE
 | |
| BEGIN_FTR_SECTION
 | |
| 	oris	r0,r0,MSR_SPE@h	 /* Disable SPE */
 | |
| 	mfspr	r12,SPRN_SPEFSCR /* save spefscr register value */
 | |
| 	stw	r12,THREAD+THREAD_SPEFSCR(r2)
 | |
| END_FTR_SECTION_IFSET(CPU_FTR_SPE)
 | |
| #endif /* CONFIG_SPE */
 | |
| 	and.	r0,r0,r11	/* FP or altivec or SPE enabled? */
 | |
| 	beq+	1f
 | |
| 	andc	r11,r11,r0
 | |
| 	MTMSRD(r11)
 | |
| 	isync
 | |
| 1:	stw	r11,_MSR(r1)
 | |
| 	mfcr	r10
 | |
| 	stw	r10,_CCR(r1)
 | |
| 	stw	r1,KSP(r3)	/* Set old stack pointer */
 | |
| 
 | |
| #ifdef CONFIG_SMP
 | |
| 	/* We need a sync somewhere here to make sure that if the
 | |
| 	 * previous task gets rescheduled on another CPU, it sees all
 | |
| 	 * stores it has performed on this one.
 | |
| 	 */
 | |
| 	sync
 | |
| #endif /* CONFIG_SMP */
 | |
| 
 | |
| 	tophys(r0,r4)
 | |
| 	CLR_TOP32(r0)
 | |
| 	mtspr	SPRN_SPRG_THREAD,r0	/* Update current THREAD phys addr */
 | |
| 	lwz	r1,KSP(r4)	/* Load new stack pointer */
 | |
| 
 | |
| 	/* save the old current 'last' for return value */
 | |
| 	mr	r3,r2
 | |
| 	addi	r2,r4,-THREAD	/* Update current */
 | |
| 
 | |
| #ifdef CONFIG_ALTIVEC
 | |
| BEGIN_FTR_SECTION
 | |
| 	lwz	r0,THREAD+THREAD_VRSAVE(r2)
 | |
| 	mtspr	SPRN_VRSAVE,r0		/* if G4, restore VRSAVE reg */
 | |
| END_FTR_SECTION_IFSET(CPU_FTR_ALTIVEC)
 | |
| #endif /* CONFIG_ALTIVEC */
 | |
| #ifdef CONFIG_SPE
 | |
| BEGIN_FTR_SECTION
 | |
| 	lwz	r0,THREAD+THREAD_SPEFSCR(r2)
 | |
| 	mtspr	SPRN_SPEFSCR,r0		/* restore SPEFSCR reg */
 | |
| END_FTR_SECTION_IFSET(CPU_FTR_SPE)
 | |
| #endif /* CONFIG_SPE */
 | |
| 
 | |
| 	lwz	r0,_CCR(r1)
 | |
| 	mtcrf	0xFF,r0
 | |
| 	/* r3-r12 are destroyed -- Cort */
 | |
| 	REST_NVGPRS(r1)
 | |
| 
 | |
| 	lwz	r4,_NIP(r1)	/* Return to _switch caller in new task */
 | |
| 	mtlr	r4
 | |
| 	addi	r1,r1,INT_FRAME_SIZE
 | |
| 	blr
 | |
| 
 | |
| 	.globl	fast_exception_return
 | |
| fast_exception_return:
 | |
| #if !(defined(CONFIG_4xx) || defined(CONFIG_BOOKE))
 | |
| 	andi.	r10,r9,MSR_RI		/* check for recoverable interrupt */
 | |
| 	beq	1f			/* if not, we've got problems */
 | |
| #endif
 | |
| 
 | |
| 2:	REST_4GPRS(3, r11)
 | |
| 	lwz	r10,_CCR(r11)
 | |
| 	REST_GPR(1, r11)
 | |
| 	mtcr	r10
 | |
| 	lwz	r10,_LINK(r11)
 | |
| 	mtlr	r10
 | |
| 	REST_GPR(10, r11)
 | |
| 	mtspr	SPRN_SRR1,r9
 | |
| 	mtspr	SPRN_SRR0,r12
 | |
| 	REST_GPR(9, r11)
 | |
| 	REST_GPR(12, r11)
 | |
| 	lwz	r11,GPR11(r11)
 | |
| 	SYNC
 | |
| 	RFI
 | |
| 
 | |
| #if !(defined(CONFIG_4xx) || defined(CONFIG_BOOKE))
 | |
| /* check if the exception happened in a restartable section */
 | |
| 1:	lis	r3,exc_exit_restart_end@ha
 | |
| 	addi	r3,r3,exc_exit_restart_end@l
 | |
| 	cmplw	r12,r3
 | |
| 	bge	3f
 | |
| 	lis	r4,exc_exit_restart@ha
 | |
| 	addi	r4,r4,exc_exit_restart@l
 | |
| 	cmplw	r12,r4
 | |
| 	blt	3f
 | |
| 	lis	r3,fee_restarts@ha
 | |
| 	tophys(r3,r3)
 | |
| 	lwz	r5,fee_restarts@l(r3)
 | |
| 	addi	r5,r5,1
 | |
| 	stw	r5,fee_restarts@l(r3)
 | |
| 	mr	r12,r4		/* restart at exc_exit_restart */
 | |
| 	b	2b
 | |
| 
 | |
| 	.section .bss
 | |
| 	.align	2
 | |
| fee_restarts:
 | |
| 	.space	4
 | |
| 	.previous
 | |
| 
 | |
| /* aargh, a nonrecoverable interrupt, panic */
 | |
| /* aargh, we don't know which trap this is */
 | |
| /* but the 601 doesn't implement the RI bit, so assume it's OK */
 | |
| 3:
 | |
| BEGIN_FTR_SECTION
 | |
| 	b	2b
 | |
| END_FTR_SECTION_IFSET(CPU_FTR_601)
 | |
| 	li	r10,-1
 | |
| 	stw	r10,_TRAP(r11)
 | |
| 	addi	r3,r1,STACK_FRAME_OVERHEAD
 | |
| 	lis	r10,MSR_KERNEL@h
 | |
| 	ori	r10,r10,MSR_KERNEL@l
 | |
| 	bl	transfer_to_handler_full
 | |
| 	.long	nonrecoverable_exception
 | |
| 	.long	ret_from_except
 | |
| #endif
 | |
| 
 | |
| 	.globl	ret_from_except_full
 | |
| ret_from_except_full:
 | |
| 	REST_NVGPRS(r1)
 | |
| 	/* fall through */
 | |
| 
 | |
| 	.globl	ret_from_except
 | |
| ret_from_except:
 | |
| 	/* Hard-disable interrupts so that current_thread_info()->flags
 | |
| 	 * can't change between when we test it and when we return
 | |
| 	 * from the interrupt. */
 | |
| 	/* Note: We don't bother telling lockdep about it */
 | |
| 	LOAD_MSR_KERNEL(r10,MSR_KERNEL)
 | |
| 	SYNC			/* Some chip revs have problems here... */
 | |
| 	MTMSRD(r10)		/* disable interrupts */
 | |
| 
 | |
| 	lwz	r3,_MSR(r1)	/* Returning to user mode? */
 | |
| 	andi.	r0,r3,MSR_PR
 | |
| 	beq	resume_kernel
 | |
| 
 | |
| user_exc_return:		/* r10 contains MSR_KERNEL here */
 | |
| 	/* Check current_thread_info()->flags */
 | |
| 	rlwinm	r9,r1,0,0,(31-THREAD_SHIFT)
 | |
| 	lwz	r9,TI_FLAGS(r9)
 | |
| 	andi.	r0,r9,_TIF_USER_WORK_MASK
 | |
| 	bne	do_work
 | |
| 
 | |
| restore_user:
 | |
| #if defined(CONFIG_4xx) || defined(CONFIG_BOOKE)
 | |
| 	/* Check whether this process has its own DBCR0 value.  The internal
 | |
| 	   debug mode bit tells us that dbcr0 should be loaded. */
 | |
| 	lwz	r0,THREAD+THREAD_DBCR0(r2)
 | |
| 	andis.	r10,r0,DBCR0_IDM@h
 | |
| 	bnel-	load_dbcr0
 | |
| #endif
 | |
| 
 | |
| #ifdef CONFIG_PREEMPT
 | |
| 	b	restore
 | |
| 
 | |
| /* N.B. the only way to get here is from the beq following ret_from_except. */
 | |
| resume_kernel:
 | |
| 	/* check current_thread_info->preempt_count */
 | |
| 	rlwinm	r9,r1,0,0,(31-THREAD_SHIFT)
 | |
| 	lwz	r0,TI_PREEMPT(r9)
 | |
| 	cmpwi	0,r0,0		/* if non-zero, just restore regs and return */
 | |
| 	bne	restore
 | |
| 	lwz	r0,TI_FLAGS(r9)
 | |
| 	andi.	r0,r0,_TIF_NEED_RESCHED
 | |
| 	beq+	restore
 | |
| 	andi.	r0,r3,MSR_EE	/* interrupts off? */
 | |
| 	beq	restore		/* don't schedule if so */
 | |
| #ifdef CONFIG_TRACE_IRQFLAGS
 | |
| 	/* Lockdep thinks irqs are enabled, we need to call
 | |
| 	 * preempt_schedule_irq with IRQs off, so we inform lockdep
 | |
| 	 * now that we -did- turn them off already
 | |
| 	 */
 | |
| 	bl	trace_hardirqs_off
 | |
| #endif
 | |
| 1:	bl	preempt_schedule_irq
 | |
| 	rlwinm	r9,r1,0,0,(31-THREAD_SHIFT)
 | |
| 	lwz	r3,TI_FLAGS(r9)
 | |
| 	andi.	r0,r3,_TIF_NEED_RESCHED
 | |
| 	bne-	1b
 | |
| #ifdef CONFIG_TRACE_IRQFLAGS
 | |
| 	/* And now, to properly rebalance the above, we tell lockdep they
 | |
| 	 * are being turned back on, which will happen when we return
 | |
| 	 */
 | |
| 	bl	trace_hardirqs_on
 | |
| #endif
 | |
| #else
 | |
| resume_kernel:
 | |
| #endif /* CONFIG_PREEMPT */
 | |
| 
 | |
| 	/* interrupts are hard-disabled at this point */
 | |
| restore:
 | |
| #ifdef CONFIG_44x
 | |
| BEGIN_MMU_FTR_SECTION
 | |
| 	b	1f
 | |
| END_MMU_FTR_SECTION_IFSET(MMU_FTR_TYPE_47x)
 | |
| 	lis	r4,icache_44x_need_flush@ha
 | |
| 	lwz	r5,icache_44x_need_flush@l(r4)
 | |
| 	cmplwi	cr0,r5,0
 | |
| 	beq+	1f
 | |
| 	li	r6,0
 | |
| 	iccci	r0,r0
 | |
| 	stw	r6,icache_44x_need_flush@l(r4)
 | |
| 1:
 | |
| #endif  /* CONFIG_44x */
 | |
| 
 | |
| 	lwz	r9,_MSR(r1)
 | |
| #ifdef CONFIG_TRACE_IRQFLAGS
 | |
| 	/* Lockdep doesn't know about the fact that IRQs are temporarily turned
 | |
| 	 * off in this assembly code while peeking at TI_FLAGS() and such. However
 | |
| 	 * we need to inform it if the exception turned interrupts off, and we
 | |
| 	 * are about to trun them back on.
 | |
| 	 *
 | |
| 	 * The problem here sadly is that we don't know whether the exceptions was
 | |
| 	 * one that turned interrupts off or not. So we always tell lockdep about
 | |
| 	 * turning them on here when we go back to wherever we came from with EE
 | |
| 	 * on, even if that may meen some redudant calls being tracked. Maybe later
 | |
| 	 * we could encode what the exception did somewhere or test the exception
 | |
| 	 * type in the pt_regs but that sounds overkill
 | |
| 	 */
 | |
| 	andi.	r10,r9,MSR_EE
 | |
| 	beq	1f
 | |
| 	bl	trace_hardirqs_on
 | |
| 	lwz	r9,_MSR(r1)
 | |
| 1:
 | |
| #endif /* CONFIG_TRACE_IRQFLAGS */
 | |
| 
 | |
| 	lwz	r0,GPR0(r1)
 | |
| 	lwz	r2,GPR2(r1)
 | |
| 	REST_4GPRS(3, r1)
 | |
| 	REST_2GPRS(7, r1)
 | |
| 
 | |
| 	lwz	r10,_XER(r1)
 | |
| 	lwz	r11,_CTR(r1)
 | |
| 	mtspr	SPRN_XER,r10
 | |
| 	mtctr	r11
 | |
| 
 | |
| 	PPC405_ERR77(0,r1)
 | |
| BEGIN_FTR_SECTION
 | |
| 	lwarx	r11,0,r1
 | |
| END_FTR_SECTION_IFSET(CPU_FTR_NEED_PAIRED_STWCX)
 | |
| 	stwcx.	r0,0,r1			/* to clear the reservation */
 | |
| 
 | |
| #if !(defined(CONFIG_4xx) || defined(CONFIG_BOOKE))
 | |
| 	andi.	r10,r9,MSR_RI		/* check if this exception occurred */
 | |
| 	beql	nonrecoverable		/* at a bad place (MSR:RI = 0) */
 | |
| 
 | |
| 	lwz	r10,_CCR(r1)
 | |
| 	lwz	r11,_LINK(r1)
 | |
| 	mtcrf	0xFF,r10
 | |
| 	mtlr	r11
 | |
| 
 | |
| 	/*
 | |
| 	 * Once we put values in SRR0 and SRR1, we are in a state
 | |
| 	 * where exceptions are not recoverable, since taking an
 | |
| 	 * exception will trash SRR0 and SRR1.  Therefore we clear the
 | |
| 	 * MSR:RI bit to indicate this.  If we do take an exception,
 | |
| 	 * we can't return to the point of the exception but we
 | |
| 	 * can restart the exception exit path at the label
 | |
| 	 * exc_exit_restart below.  -- paulus
 | |
| 	 */
 | |
| 	LOAD_MSR_KERNEL(r10,MSR_KERNEL & ~MSR_RI)
 | |
| 	SYNC
 | |
| 	MTMSRD(r10)		/* clear the RI bit */
 | |
| 	.globl exc_exit_restart
 | |
| exc_exit_restart:
 | |
| 	lwz	r12,_NIP(r1)
 | |
| 	FIX_SRR1(r9,r10)
 | |
| 	mtspr	SPRN_SRR0,r12
 | |
| 	mtspr	SPRN_SRR1,r9
 | |
| 	REST_4GPRS(9, r1)
 | |
| 	lwz	r1,GPR1(r1)
 | |
| 	.globl exc_exit_restart_end
 | |
| exc_exit_restart_end:
 | |
| 	SYNC
 | |
| 	RFI
 | |
| 
 | |
| #else /* !(CONFIG_4xx || CONFIG_BOOKE) */
 | |
| 	/*
 | |
| 	 * This is a bit different on 4xx/Book-E because it doesn't have
 | |
| 	 * the RI bit in the MSR.
 | |
| 	 * The TLB miss handler checks if we have interrupted
 | |
| 	 * the exception exit path and restarts it if so
 | |
| 	 * (well maybe one day it will... :).
 | |
| 	 */
 | |
| 	lwz	r11,_LINK(r1)
 | |
| 	mtlr	r11
 | |
| 	lwz	r10,_CCR(r1)
 | |
| 	mtcrf	0xff,r10
 | |
| 	REST_2GPRS(9, r1)
 | |
| 	.globl exc_exit_restart
 | |
| exc_exit_restart:
 | |
| 	lwz	r11,_NIP(r1)
 | |
| 	lwz	r12,_MSR(r1)
 | |
| exc_exit_start:
 | |
| 	mtspr	SPRN_SRR0,r11
 | |
| 	mtspr	SPRN_SRR1,r12
 | |
| 	REST_2GPRS(11, r1)
 | |
| 	lwz	r1,GPR1(r1)
 | |
| 	.globl exc_exit_restart_end
 | |
| exc_exit_restart_end:
 | |
| 	PPC405_ERR77_SYNC
 | |
| 	rfi
 | |
| 	b	.			/* prevent prefetch past rfi */
 | |
| 
 | |
| /*
 | |
|  * Returning from a critical interrupt in user mode doesn't need
 | |
|  * to be any different from a normal exception.  For a critical
 | |
|  * interrupt in the kernel, we just return (without checking for
 | |
|  * preemption) since the interrupt may have happened at some crucial
 | |
|  * place (e.g. inside the TLB miss handler), and because we will be
 | |
|  * running with r1 pointing into critical_stack, not the current
 | |
|  * process's kernel stack (and therefore current_thread_info() will
 | |
|  * give the wrong answer).
 | |
|  * We have to restore various SPRs that may have been in use at the
 | |
|  * time of the critical interrupt.
 | |
|  *
 | |
|  */
 | |
| #ifdef CONFIG_40x
 | |
| #define PPC_40x_TURN_OFF_MSR_DR						    \
 | |
| 	/* avoid any possible TLB misses here by turning off MSR.DR, we	    \
 | |
| 	 * assume the instructions here are mapped by a pinned TLB entry */ \
 | |
| 	li	r10,MSR_IR;						    \
 | |
| 	mtmsr	r10;							    \
 | |
| 	isync;								    \
 | |
| 	tophys(r1, r1);
 | |
| #else
 | |
| #define PPC_40x_TURN_OFF_MSR_DR
 | |
| #endif
 | |
| 
 | |
| #define RET_FROM_EXC_LEVEL(exc_lvl_srr0, exc_lvl_srr1, exc_lvl_rfi)	\
 | |
| 	REST_NVGPRS(r1);						\
 | |
| 	lwz	r3,_MSR(r1);						\
 | |
| 	andi.	r3,r3,MSR_PR;						\
 | |
| 	LOAD_MSR_KERNEL(r10,MSR_KERNEL);				\
 | |
| 	bne	user_exc_return;					\
 | |
| 	lwz	r0,GPR0(r1);						\
 | |
| 	lwz	r2,GPR2(r1);						\
 | |
| 	REST_4GPRS(3, r1);						\
 | |
| 	REST_2GPRS(7, r1);						\
 | |
| 	lwz	r10,_XER(r1);						\
 | |
| 	lwz	r11,_CTR(r1);						\
 | |
| 	mtspr	SPRN_XER,r10;						\
 | |
| 	mtctr	r11;							\
 | |
| 	PPC405_ERR77(0,r1);						\
 | |
| 	stwcx.	r0,0,r1;		/* to clear the reservation */	\
 | |
| 	lwz	r11,_LINK(r1);						\
 | |
| 	mtlr	r11;							\
 | |
| 	lwz	r10,_CCR(r1);						\
 | |
| 	mtcrf	0xff,r10;						\
 | |
| 	PPC_40x_TURN_OFF_MSR_DR;					\
 | |
| 	lwz	r9,_DEAR(r1);						\
 | |
| 	lwz	r10,_ESR(r1);						\
 | |
| 	mtspr	SPRN_DEAR,r9;						\
 | |
| 	mtspr	SPRN_ESR,r10;						\
 | |
| 	lwz	r11,_NIP(r1);						\
 | |
| 	lwz	r12,_MSR(r1);						\
 | |
| 	mtspr	exc_lvl_srr0,r11;					\
 | |
| 	mtspr	exc_lvl_srr1,r12;					\
 | |
| 	lwz	r9,GPR9(r1);						\
 | |
| 	lwz	r12,GPR12(r1);						\
 | |
| 	lwz	r10,GPR10(r1);						\
 | |
| 	lwz	r11,GPR11(r1);						\
 | |
| 	lwz	r1,GPR1(r1);						\
 | |
| 	PPC405_ERR77_SYNC;						\
 | |
| 	exc_lvl_rfi;							\
 | |
| 	b	.;		/* prevent prefetch past exc_lvl_rfi */
 | |
| 
 | |
| #define	RESTORE_xSRR(exc_lvl_srr0, exc_lvl_srr1)			\
 | |
| 	lwz	r9,_##exc_lvl_srr0(r1);					\
 | |
| 	lwz	r10,_##exc_lvl_srr1(r1);				\
 | |
| 	mtspr	SPRN_##exc_lvl_srr0,r9;					\
 | |
| 	mtspr	SPRN_##exc_lvl_srr1,r10;
 | |
| 
 | |
| #if defined(CONFIG_PPC_BOOK3E_MMU)
 | |
| #ifdef CONFIG_PHYS_64BIT
 | |
| #define	RESTORE_MAS7							\
 | |
| 	lwz	r11,MAS7(r1);						\
 | |
| 	mtspr	SPRN_MAS7,r11;
 | |
| #else
 | |
| #define	RESTORE_MAS7
 | |
| #endif /* CONFIG_PHYS_64BIT */
 | |
| #define RESTORE_MMU_REGS						\
 | |
| 	lwz	r9,MAS0(r1);						\
 | |
| 	lwz	r10,MAS1(r1);						\
 | |
| 	lwz	r11,MAS2(r1);						\
 | |
| 	mtspr	SPRN_MAS0,r9;						\
 | |
| 	lwz	r9,MAS3(r1);						\
 | |
| 	mtspr	SPRN_MAS1,r10;						\
 | |
| 	lwz	r10,MAS6(r1);						\
 | |
| 	mtspr	SPRN_MAS2,r11;						\
 | |
| 	mtspr	SPRN_MAS3,r9;						\
 | |
| 	mtspr	SPRN_MAS6,r10;						\
 | |
| 	RESTORE_MAS7;
 | |
| #elif defined(CONFIG_44x)
 | |
| #define RESTORE_MMU_REGS						\
 | |
| 	lwz	r9,MMUCR(r1);						\
 | |
| 	mtspr	SPRN_MMUCR,r9;
 | |
| #else
 | |
| #define RESTORE_MMU_REGS
 | |
| #endif
 | |
| 
 | |
| #ifdef CONFIG_40x
 | |
| 	.globl	ret_from_crit_exc
 | |
| ret_from_crit_exc:
 | |
| 	mfspr	r9,SPRN_SPRG_THREAD
 | |
| 	lis	r10,saved_ksp_limit@ha;
 | |
| 	lwz	r10,saved_ksp_limit@l(r10);
 | |
| 	tovirt(r9,r9);
 | |
| 	stw	r10,KSP_LIMIT(r9)
 | |
| 	lis	r9,crit_srr0@ha;
 | |
| 	lwz	r9,crit_srr0@l(r9);
 | |
| 	lis	r10,crit_srr1@ha;
 | |
| 	lwz	r10,crit_srr1@l(r10);
 | |
| 	mtspr	SPRN_SRR0,r9;
 | |
| 	mtspr	SPRN_SRR1,r10;
 | |
| 	RET_FROM_EXC_LEVEL(SPRN_CSRR0, SPRN_CSRR1, PPC_RFCI)
 | |
| #endif /* CONFIG_40x */
 | |
| 
 | |
| #ifdef CONFIG_BOOKE
 | |
| 	.globl	ret_from_crit_exc
 | |
| ret_from_crit_exc:
 | |
| 	mfspr	r9,SPRN_SPRG_THREAD
 | |
| 	lwz	r10,SAVED_KSP_LIMIT(r1)
 | |
| 	stw	r10,KSP_LIMIT(r9)
 | |
| 	RESTORE_xSRR(SRR0,SRR1);
 | |
| 	RESTORE_MMU_REGS;
 | |
| 	RET_FROM_EXC_LEVEL(SPRN_CSRR0, SPRN_CSRR1, PPC_RFCI)
 | |
| 
 | |
| 	.globl	ret_from_debug_exc
 | |
| ret_from_debug_exc:
 | |
| 	mfspr	r9,SPRN_SPRG_THREAD
 | |
| 	lwz	r10,SAVED_KSP_LIMIT(r1)
 | |
| 	stw	r10,KSP_LIMIT(r9)
 | |
| 	lwz	r9,THREAD_INFO-THREAD(r9)
 | |
| 	rlwinm	r10,r1,0,0,(31-THREAD_SHIFT)
 | |
| 	lwz	r10,TI_PREEMPT(r10)
 | |
| 	stw	r10,TI_PREEMPT(r9)
 | |
| 	RESTORE_xSRR(SRR0,SRR1);
 | |
| 	RESTORE_xSRR(CSRR0,CSRR1);
 | |
| 	RESTORE_MMU_REGS;
 | |
| 	RET_FROM_EXC_LEVEL(SPRN_DSRR0, SPRN_DSRR1, PPC_RFDI)
 | |
| 
 | |
| 	.globl	ret_from_mcheck_exc
 | |
| ret_from_mcheck_exc:
 | |
| 	mfspr	r9,SPRN_SPRG_THREAD
 | |
| 	lwz	r10,SAVED_KSP_LIMIT(r1)
 | |
| 	stw	r10,KSP_LIMIT(r9)
 | |
| 	RESTORE_xSRR(SRR0,SRR1);
 | |
| 	RESTORE_xSRR(CSRR0,CSRR1);
 | |
| 	RESTORE_xSRR(DSRR0,DSRR1);
 | |
| 	RESTORE_MMU_REGS;
 | |
| 	RET_FROM_EXC_LEVEL(SPRN_MCSRR0, SPRN_MCSRR1, PPC_RFMCI)
 | |
| #endif /* CONFIG_BOOKE */
 | |
| 
 | |
| /*
 | |
|  * Load the DBCR0 value for a task that is being ptraced,
 | |
|  * having first saved away the global DBCR0.  Note that r0
 | |
|  * has the dbcr0 value to set upon entry to this.
 | |
|  */
 | |
| load_dbcr0:
 | |
| 	mfmsr	r10		/* first disable debug exceptions */
 | |
| 	rlwinm	r10,r10,0,~MSR_DE
 | |
| 	mtmsr	r10
 | |
| 	isync
 | |
| 	mfspr	r10,SPRN_DBCR0
 | |
| 	lis	r11,global_dbcr0@ha
 | |
| 	addi	r11,r11,global_dbcr0@l
 | |
| #ifdef CONFIG_SMP
 | |
| 	rlwinm	r9,r1,0,0,(31-THREAD_SHIFT)
 | |
| 	lwz	r9,TI_CPU(r9)
 | |
| 	slwi	r9,r9,3
 | |
| 	add	r11,r11,r9
 | |
| #endif
 | |
| 	stw	r10,0(r11)
 | |
| 	mtspr	SPRN_DBCR0,r0
 | |
| 	lwz	r10,4(r11)
 | |
| 	addi	r10,r10,1
 | |
| 	stw	r10,4(r11)
 | |
| 	li	r11,-1
 | |
| 	mtspr	SPRN_DBSR,r11	/* clear all pending debug events */
 | |
| 	blr
 | |
| 
 | |
| 	.section .bss
 | |
| 	.align	4
 | |
| global_dbcr0:
 | |
| 	.space	8*NR_CPUS
 | |
| 	.previous
 | |
| #endif /* !(CONFIG_4xx || CONFIG_BOOKE) */
 | |
| 
 | |
| do_work:			/* r10 contains MSR_KERNEL here */
 | |
| 	andi.	r0,r9,_TIF_NEED_RESCHED
 | |
| 	beq	do_user_signal
 | |
| 
 | |
| do_resched:			/* r10 contains MSR_KERNEL here */
 | |
| 	/* Note: We don't need to inform lockdep that we are enabling
 | |
| 	 * interrupts here. As far as it knows, they are already enabled
 | |
| 	 */
 | |
| 	ori	r10,r10,MSR_EE
 | |
| 	SYNC
 | |
| 	MTMSRD(r10)		/* hard-enable interrupts */
 | |
| 	bl	schedule
 | |
| recheck:
 | |
| 	/* Note: And we don't tell it we are disabling them again
 | |
| 	 * neither. Those disable/enable cycles used to peek at
 | |
| 	 * TI_FLAGS aren't advertised.
 | |
| 	 */
 | |
| 	LOAD_MSR_KERNEL(r10,MSR_KERNEL)
 | |
| 	SYNC
 | |
| 	MTMSRD(r10)		/* disable interrupts */
 | |
| 	rlwinm	r9,r1,0,0,(31-THREAD_SHIFT)
 | |
| 	lwz	r9,TI_FLAGS(r9)
 | |
| 	andi.	r0,r9,_TIF_NEED_RESCHED
 | |
| 	bne-	do_resched
 | |
| 	andi.	r0,r9,_TIF_USER_WORK_MASK
 | |
| 	beq	restore_user
 | |
| do_user_signal:			/* r10 contains MSR_KERNEL here */
 | |
| 	ori	r10,r10,MSR_EE
 | |
| 	SYNC
 | |
| 	MTMSRD(r10)		/* hard-enable interrupts */
 | |
| 	/* save r13-r31 in the exception frame, if not already done */
 | |
| 	lwz	r3,_TRAP(r1)
 | |
| 	andi.	r0,r3,1
 | |
| 	beq	2f
 | |
| 	SAVE_NVGPRS(r1)
 | |
| 	rlwinm	r3,r3,0,0,30
 | |
| 	stw	r3,_TRAP(r1)
 | |
| 2:	addi	r3,r1,STACK_FRAME_OVERHEAD
 | |
| 	mr	r4,r9
 | |
| 	bl	do_signal
 | |
| 	REST_NVGPRS(r1)
 | |
| 	b	recheck
 | |
| 
 | |
| /*
 | |
|  * We come here when we are at the end of handling an exception
 | |
|  * that occurred at a place where taking an exception will lose
 | |
|  * state information, such as the contents of SRR0 and SRR1.
 | |
|  */
 | |
| nonrecoverable:
 | |
| 	lis	r10,exc_exit_restart_end@ha
 | |
| 	addi	r10,r10,exc_exit_restart_end@l
 | |
| 	cmplw	r12,r10
 | |
| 	bge	3f
 | |
| 	lis	r11,exc_exit_restart@ha
 | |
| 	addi	r11,r11,exc_exit_restart@l
 | |
| 	cmplw	r12,r11
 | |
| 	blt	3f
 | |
| 	lis	r10,ee_restarts@ha
 | |
| 	lwz	r12,ee_restarts@l(r10)
 | |
| 	addi	r12,r12,1
 | |
| 	stw	r12,ee_restarts@l(r10)
 | |
| 	mr	r12,r11		/* restart at exc_exit_restart */
 | |
| 	blr
 | |
| 3:	/* OK, we can't recover, kill this process */
 | |
| 	/* but the 601 doesn't implement the RI bit, so assume it's OK */
 | |
| BEGIN_FTR_SECTION
 | |
| 	blr
 | |
| END_FTR_SECTION_IFSET(CPU_FTR_601)
 | |
| 	lwz	r3,_TRAP(r1)
 | |
| 	andi.	r0,r3,1
 | |
| 	beq	4f
 | |
| 	SAVE_NVGPRS(r1)
 | |
| 	rlwinm	r3,r3,0,0,30
 | |
| 	stw	r3,_TRAP(r1)
 | |
| 4:	addi	r3,r1,STACK_FRAME_OVERHEAD
 | |
| 	bl	nonrecoverable_exception
 | |
| 	/* shouldn't return */
 | |
| 	b	4b
 | |
| 
 | |
| 	.section .bss
 | |
| 	.align	2
 | |
| ee_restarts:
 | |
| 	.space	4
 | |
| 	.previous
 | |
| 
 | |
| /*
 | |
|  * PROM code for specific machines follows.  Put it
 | |
|  * here so it's easy to add arch-specific sections later.
 | |
|  * -- Cort
 | |
|  */
 | |
| #ifdef CONFIG_PPC_RTAS
 | |
| /*
 | |
|  * On CHRP, the Run-Time Abstraction Services (RTAS) have to be
 | |
|  * called with the MMU off.
 | |
|  */
 | |
| _GLOBAL(enter_rtas)
 | |
| 	stwu	r1,-INT_FRAME_SIZE(r1)
 | |
| 	mflr	r0
 | |
| 	stw	r0,INT_FRAME_SIZE+4(r1)
 | |
| 	LOAD_REG_ADDR(r4, rtas)
 | |
| 	lis	r6,1f@ha	/* physical return address for rtas */
 | |
| 	addi	r6,r6,1f@l
 | |
| 	tophys(r6,r6)
 | |
| 	tophys(r7,r1)
 | |
| 	lwz	r8,RTASENTRY(r4)
 | |
| 	lwz	r4,RTASBASE(r4)
 | |
| 	mfmsr	r9
 | |
| 	stw	r9,8(r1)
 | |
| 	LOAD_MSR_KERNEL(r0,MSR_KERNEL)
 | |
| 	SYNC			/* disable interrupts so SRR0/1 */
 | |
| 	MTMSRD(r0)		/* don't get trashed */
 | |
| 	li	r9,MSR_KERNEL & ~(MSR_IR|MSR_DR)
 | |
| 	mtlr	r6
 | |
| 	mtspr	SPRN_SPRG_RTAS,r7
 | |
| 	mtspr	SPRN_SRR0,r8
 | |
| 	mtspr	SPRN_SRR1,r9
 | |
| 	RFI
 | |
| 1:	tophys(r9,r1)
 | |
| 	lwz	r8,INT_FRAME_SIZE+4(r9)	/* get return address */
 | |
| 	lwz	r9,8(r9)	/* original msr value */
 | |
| 	FIX_SRR1(r9,r0)
 | |
| 	addi	r1,r1,INT_FRAME_SIZE
 | |
| 	li	r0,0
 | |
| 	mtspr	SPRN_SPRG_RTAS,r0
 | |
| 	mtspr	SPRN_SRR0,r8
 | |
| 	mtspr	SPRN_SRR1,r9
 | |
| 	RFI			/* return to caller */
 | |
| 
 | |
| 	.globl	machine_check_in_rtas
 | |
| machine_check_in_rtas:
 | |
| 	twi	31,0,0
 | |
| 	/* XXX load up BATs and panic */
 | |
| 
 | |
| #endif /* CONFIG_PPC_RTAS */
 | |
| 
 | |
| #ifdef CONFIG_FUNCTION_TRACER
 | |
| #ifdef CONFIG_DYNAMIC_FTRACE
 | |
| _GLOBAL(mcount)
 | |
| _GLOBAL(_mcount)
 | |
| 	/*
 | |
| 	 * It is required that _mcount on PPC32 must preserve the
 | |
| 	 * link register. But we have r0 to play with. We use r0
 | |
| 	 * to push the return address back to the caller of mcount
 | |
| 	 * into the ctr register, restore the link register and
 | |
| 	 * then jump back using the ctr register.
 | |
| 	 */
 | |
| 	mflr	r0
 | |
| 	mtctr	r0
 | |
| 	lwz	r0, 4(r1)
 | |
| 	mtlr	r0
 | |
| 	bctr
 | |
| 
 | |
| _GLOBAL(ftrace_caller)
 | |
| 	MCOUNT_SAVE_FRAME
 | |
| 	/* r3 ends up with link register */
 | |
| 	subi	r3, r3, MCOUNT_INSN_SIZE
 | |
| .globl ftrace_call
 | |
| ftrace_call:
 | |
| 	bl	ftrace_stub
 | |
| 	nop
 | |
| #ifdef CONFIG_FUNCTION_GRAPH_TRACER
 | |
| .globl ftrace_graph_call
 | |
| ftrace_graph_call:
 | |
| 	b	ftrace_graph_stub
 | |
| _GLOBAL(ftrace_graph_stub)
 | |
| #endif
 | |
| 	MCOUNT_RESTORE_FRAME
 | |
| 	/* old link register ends up in ctr reg */
 | |
| 	bctr
 | |
| #else
 | |
| _GLOBAL(mcount)
 | |
| _GLOBAL(_mcount)
 | |
| 
 | |
| 	MCOUNT_SAVE_FRAME
 | |
| 
 | |
| 	subi	r3, r3, MCOUNT_INSN_SIZE
 | |
| 	LOAD_REG_ADDR(r5, ftrace_trace_function)
 | |
| 	lwz	r5,0(r5)
 | |
| 
 | |
| 	mtctr	r5
 | |
| 	bctrl
 | |
| 	nop
 | |
| 
 | |
| #ifdef CONFIG_FUNCTION_GRAPH_TRACER
 | |
| 	b	ftrace_graph_caller
 | |
| #endif
 | |
| 	MCOUNT_RESTORE_FRAME
 | |
| 	bctr
 | |
| #endif
 | |
| 
 | |
| _GLOBAL(ftrace_stub)
 | |
| 	blr
 | |
| 
 | |
| #ifdef CONFIG_FUNCTION_GRAPH_TRACER
 | |
| _GLOBAL(ftrace_graph_caller)
 | |
| 	/* load r4 with local address */
 | |
| 	lwz	r4, 44(r1)
 | |
| 	subi	r4, r4, MCOUNT_INSN_SIZE
 | |
| 
 | |
| 	/* get the parent address */
 | |
| 	addi	r3, r1, 52
 | |
| 
 | |
| 	bl	prepare_ftrace_return
 | |
| 	nop
 | |
| 
 | |
| 	MCOUNT_RESTORE_FRAME
 | |
| 	/* old link register ends up in ctr reg */
 | |
| 	bctr
 | |
| 
 | |
| _GLOBAL(return_to_handler)
 | |
| 	/* need to save return values */
 | |
| 	stwu	r1, -32(r1)
 | |
| 	stw	r3, 20(r1)
 | |
| 	stw	r4, 16(r1)
 | |
| 	stw	r31, 12(r1)
 | |
| 	mr	r31, r1
 | |
| 
 | |
| 	bl	ftrace_return_to_handler
 | |
| 	nop
 | |
| 
 | |
| 	/* return value has real return address */
 | |
| 	mtlr	r3
 | |
| 
 | |
| 	lwz	r3, 20(r1)
 | |
| 	lwz	r4, 16(r1)
 | |
| 	lwz	r31,12(r1)
 | |
| 	lwz	r1, 0(r1)
 | |
| 
 | |
| 	/* Jump back to real return address */
 | |
| 	blr
 | |
| #endif /* CONFIG_FUNCTION_GRAPH_TRACER */
 | |
| 
 | |
| #endif /* CONFIG_MCOUNT */
 |