/* * arch/score/kernel/entry.S * * Score Processor version. * * Copyright (C) 2009 Sunplus Core Technology Co., Ltd. *  Chen Liqin <liqin.chen@sunplusct.com> *  Lennox Wu <lennox.wu@sunplusct.com> * * 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. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, see the file COPYING, or write * to the Free Software Foundation, Inc., * 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA */ #include <linux/err.h>#include <linux/init.h>#include <linux/linkage.h> #include <asm/asmmacro.h>#include <asm/thread_info.h>#include <asm/unistd.h> /* * disable interrupts. */.macro	disable_irq	mfcr	r8, cr0	srli	r8, r8, 1	slli	r8, r8, 1	mtcr	r8, cr0	nop	nop	nop	nop	nop.endm /* * enable interrupts. */.macro	enable_irq	mfcr	r8, cr0	ori	r8, 1	mtcr	r8, cr0	nop	nop	nop	nop	nop.endm __INITENTRY(debug_exception_vector)	nop!	nop!	nop!	nop!	nop!	nop!	nop!	nop! ENTRY(general_exception_vector)			# should move to addr 0x200	j	general_exception	nop!	nop!	nop!	nop!	nop!	nop! ENTRY(interrupt_exception_vector)		# should move to addr 0x210	j	interrupt_exception	nop!	nop!	nop!	nop!	nop!	nop! 	.section ".text", "ax"	.align	2;general_exception:	mfcr	r31, cr2	nop	la	r30, exception_handlers	andi	r31, 0x1f			# get ecr.exc_code	slli	r31, r31, 2	add	r30, r30, r31	lw	r30, [r30]	br	r30 interrupt_exception:	SAVE_ALL	mfcr	r4, cr2	nop	lw	r16, [r28, TI_REGS]	sw	r0, [r28, TI_REGS]	la	r3, ret_from_irq	srli	r4, r4, 18			# get ecr.ip[7:2], interrupt No.	mv	r5, r0	j	do_IRQ ENTRY(handle_nmi)				# NMI #1	SAVE_ALL	mv	r4, r0	la	r8, nmi_exception_handler	brl	r8	j	restore_all ENTRY(handle_adelinsn)				# AdEL-instruction #2	SAVE_ALL	mfcr	r8, cr6	nop	nop	sw	r8, [r0, PT_EMA]	mv	r4, r0	la	r8, do_adelinsn	brl	r8	mv	r4, r0	j	ret_from_exception	nop ENTRY(handle_ibe)				# BusEL-instruction #5	SAVE_ALL	mv	r4, r0	la	r8, do_be	brl	r8	mv	r4, r0	j	ret_from_exception	nop ENTRY(handle_pel)				# P-EL #6	SAVE_ALL	mv	r4, r0	la	r8, do_pel	brl	r8	mv	r4, r0	j	ret_from_exception	nop ENTRY(handle_ccu)				# CCU #8	SAVE_ALL	mv	r4, r0	la	r8, do_ccu	brl	r8	mv	r4, r0	j	ret_from_exception	nop ENTRY(handle_ri)				# RI #9	SAVE_ALL	mv	r4, r0	la	r8, do_ri	brl	r8	mv	r4, r0	j	ret_from_exception	nop ENTRY(handle_tr)				# Trap #10	SAVE_ALL	mv	r4, r0	la	r8, do_tr	brl	r8	mv	r4, r0	j	ret_from_exception	nop ENTRY(handle_adedata)				# AdES-instruction #12	SAVE_ALL	mfcr	r8, cr6	nop	nop	sw	r8, [r0, PT_EMA]	mv	r4, r0	la	r8, do_adedata	brl	r8	mv	r4, r0	j	ret_from_exception	nop ENTRY(handle_cee)				# CeE #16	SAVE_ALL	mv	r4, r0	la	r8, do_cee	brl	r8	mv	r4, r0	j	ret_from_exception	nop ENTRY(handle_cpe)				# CpE #17	SAVE_ALL	mv	r4, r0	la	r8, do_cpe	brl	r8	mv	r4, r0	j	ret_from_exception	nop ENTRY(handle_dbe)				# BusEL-data #18	SAVE_ALL	mv	r4, r0	la	r8, do_be	brl	r8	mv	r4, r0	j	ret_from_exception	nop ENTRY(handle_reserved)				# others	SAVE_ALL	mv	r4, r0	la	r8, do_reserved	brl	r8	mv	r4, r0	j	ret_from_exception	nop #ifndef CONFIG_PREEMPT#define resume_kernel	restore_all#else#define __ret_from_irq	ret_from_exception#endif 	.align	2#ifndef CONFIG_PREEMPTENTRY(ret_from_exception)	disable_irq			# preempt stop	nop	j	__ret_from_irq	nop#endif ENTRY(ret_from_irq)	sw	r16, [r28, TI_REGS] ENTRY(__ret_from_irq)	lw	r8, [r0, PT_PSR]	# returning to kernel mode?	andri.c	r8, r8, KU_USER	beq	resume_kernel resume_userspace:	disable_irq	lw	r6, [r28, TI_FLAGS]	# current->work	li	r8, _TIF_WORK_MASK	and.c	r8, r8, r6		# ignoring syscall_trace	bne	work_pending	nop	j	restore_all	nop #ifdef CONFIG_PREEMPTresume_kernel:	disable_irq	lw	r8, [r28, TI_PRE_COUNT]	cmpz.c	r8	bne	restore_allneed_resched:	lw	r8, [r28, TI_FLAGS]	andri.c	r9, r8, _TIF_NEED_RESCHED	beq	restore_all	lw	r8, [r28, PT_PSR]		# Interrupts off?	andri.c	r8, r8, 1	beq	restore_all	bl	preempt_schedule_irq	nop	j	need_resched	nop#endif ENTRY(ret_from_kernel_thread)	bl	schedule_tail			# r4=struct task_struct *prev	nop	mv	r4, r13	brl	r12	j	syscall_exit ENTRY(ret_from_fork)	bl	schedule_tail			# r4=struct task_struct *prev ENTRY(syscall_exit)	nop	disable_irq	lw	r6, [r28, TI_FLAGS]		# current->work	li	r8, _TIF_WORK_MASK	and.c	r8, r6, r8	bne	syscall_exit_work ENTRY(restore_all)					# restore full frame	RESTORE_ALL_AND_RET work_pending:	andri.c	r8, r6, _TIF_NEED_RESCHED # r6 is preloaded with TI_FLAGS	beq	work_notifysigwork_resched:	bl	schedule	nop	disable_irq	lw	r6, [r28, TI_FLAGS]	li	r8, _TIF_WORK_MASK	and.c	r8, r6, r8	# is there any work to be done				# other than syscall tracing?	beq	restore_all	andri.c	r8, r6, _TIF_NEED_RESCHED	bne	work_resched work_notifysig:	mv	r4, r0	li	r5, 0	bl	do_notify_resume	# r6 already loaded	nop	j	resume_userspace	nop ENTRY(syscall_exit_work)	li	r8, _TIF_SYSCALL_TRACE	and.c	r8, r8, r6		# r6 is preloaded with TI_FLAGS	beq	work_pending		# trace bit set?	nop	enable_irq	mv	r4, r0	li	r5, 1	bl	do_syscall_trace	nop	b	resume_userspace	nop .macro	save_context	reg	sw	r12, [\reg, THREAD_REG12];	sw	r13, [\reg, THREAD_REG13];	sw	r14, [\reg, THREAD_REG14];	sw	r15, [\reg, THREAD_REG15];	sw	r16, [\reg, THREAD_REG16];	sw	r17, [\reg, THREAD_REG17];	sw	r18, [\reg, THREAD_REG18];	sw	r19, [\reg, THREAD_REG19];	sw	r20, [\reg, THREAD_REG20];	sw	r21, [\reg, THREAD_REG21];	sw	r29, [\reg, THREAD_REG29];	sw	r2, [\reg, THREAD_REG2];	sw	r0, [\reg, THREAD_REG0].endm .macro	restore_context	reg	lw	r12, [\reg, THREAD_REG12];	lw	r13, [\reg, THREAD_REG13];	lw	r14, [\reg, THREAD_REG14];	lw	r15, [\reg, THREAD_REG15];	lw	r16, [\reg, THREAD_REG16];	lw	r17, [\reg, THREAD_REG17];	lw	r18, [\reg, THREAD_REG18];	lw	r19, [\reg, THREAD_REG19];	lw	r20, [\reg, THREAD_REG20];	lw	r21, [\reg, THREAD_REG21];	lw	r29, [\reg, THREAD_REG29];	lw	r0, [\reg, THREAD_REG0];	lw	r2, [\reg, THREAD_REG2];	lw	r3, [\reg, THREAD_REG3].endm /* * task_struct *resume(task_struct *prev, task_struct *next, *			struct thread_info *next_ti) */ENTRY(resume)	mfcr	r9, cr0	nop	nop	sw	r9, [r4, THREAD_PSR]	save_context	r4	sw	r3, [r4, THREAD_REG3] 	mv	r28, r6	restore_context	r5	mv	r8, r6	addi	r8, KERNEL_STACK_SIZE	subi	r8, 32	la 	r9, kernelsp;	sw 	r8, [r9]; 	mfcr	r9, cr0	ldis	r7, 0x00ff	nop	and	r9, r9, r7	lw	r6, [r5, THREAD_PSR]	not	r7, r7	and	r6, r6, r7	or	r6, r6, r9	mtcr	r6, cr0	nop; nop; nop; nop; nop	br	r3 ENTRY(handle_sys)	SAVE_ALL	sw	r8, [r0, 16]		# argument 5 from user r8	sw	r9, [r0, 20]		# argument 6 from user r9	enable_irq 	sw	r4, [r0, PT_ORIG_R4]	#for restart syscall	sw	r7, [r0, PT_ORIG_R7]	#for restart syscall	sw	r27, [r0, PT_IS_SYSCALL] # it from syscall 	lw	r9, [r0, PT_EPC]	# skip syscall on return	addi	r9, 4	sw	r9, [r0, PT_EPC] 	cmpi.c	r27, __NR_syscalls 	# check syscall number	bcs	illegal_syscall 	slli	r8, r27, 2		# get syscall routine	la	r11, sys_call_table	add	r11, r11, r8	lw	r10, [r11]		# get syscall entry 	cmpz.c	r10	beq	illegal_syscall 	lw	r8, [r28, TI_FLAGS]	li	r9, _TIF_SYSCALL_TRACE	and.c	r8, r8, r9	bne	syscall_trace_entry 	brl	r10			# Do The Real system call 	cmpi.c	r4, 0	blt	1f	ldi	r8, 0	sw	r8, [r0, PT_R7]	b 2f1:	cmpi.c	r4, -MAX_ERRNO - 1	ble	2f	ldi	r8, 0x1;	sw	r8, [r0, PT_R7]	neg	r4, r42:	sw	r4, [r0, PT_R4]		# save result syscall_return:	disable_irq	lw	r6, [r28, TI_FLAGS]	# current->work	li	r8, _TIF_WORK_MASK	and.c	r8, r6, r8	bne	syscall_return_work	j	restore_all syscall_return_work:	j	syscall_exit_work syscall_trace_entry:	mv	r16, r10	mv	r4, r0	li	r5, 0	bl	do_syscall_trace 	mv	r8, r16	lw	r4, [r0, PT_R4]		# Restore argument registers	lw	r5, [r0, PT_R5]	lw	r6, [r0, PT_R6]	lw	r7, [r0, PT_R7]	brl	r8 	li	r8, -MAX_ERRNO - 1	sw	r8, [r0, PT_R7]		# set error flag 	neg	r4, r4			# error	sw	r4, [r0, PT_R0]		# set flag for syscall					# restarting1:	sw	r4, [r0, PT_R2]		# result	j	syscall_exit illegal_syscall:	ldi	r4, -ENOSYS		# error	sw	r4, [r0, PT_ORIG_R4]	sw	r4, [r0, PT_R4]	ldi	r9, 1			# set error flag	sw	r9, [r0, PT_R7]	j	syscall_return ENTRY(sys_rt_sigreturn)	mv	r4, r0	la	r8, score_rt_sigreturn	br	r8