| /* | 
 |  * (C) Copyright 2004, Psyent Corporation <www.psyent.com> | 
 |  * Scott McNutt <smcnutt@psyent.com> | 
 |  * | 
 |  * See file CREDITS for list of people who contributed to this | 
 |  * project. | 
 |  * | 
 |  * 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, write to the Free Software | 
 |  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, | 
 |  * MA 02111-1307 USA | 
 |  */ | 
 |  | 
 | #include <config.h> | 
 | #include <asm/opcodes.h> | 
 |  | 
 |  | 
 | 	.text | 
 | 	.align	4 | 
 |  | 
 | 	.global _exception | 
 |  | 
 | 	.set noat | 
 | 	.set nobreak | 
 |  | 
 | _exception: | 
 | 	/* SAVE ALL REGS -- this allows trap and unimplemented | 
 | 	 * instruction handlers to be coded conveniently in C | 
 | 	 */ | 
 | 	addi	sp, sp, -(33*4) | 
 | 	stw	r0, 0(sp) | 
 | 	stw	r1, 4(sp) | 
 | 	stw	r2, 8(sp) | 
 | 	stw	r3, 12(sp) | 
 | 	stw	r4, 16(sp) | 
 | 	stw	r5, 20(sp) | 
 | 	stw	r6, 24(sp) | 
 | 	stw	r7, 28(sp) | 
 | 	stw	r8, 32(sp) | 
 | 	stw	r9, 36(sp) | 
 | 	stw	r10, 40(sp) | 
 | 	stw	r11, 44(sp) | 
 | 	stw	r12, 48(sp) | 
 | 	stw	r13, 52(sp) | 
 | 	stw	r14, 56(sp) | 
 | 	stw	r15, 60(sp) | 
 | 	stw	r16, 64(sp) | 
 | 	stw	r17, 68(sp) | 
 | 	stw	r19, 72(sp) | 
 | 	stw	r19, 76(sp) | 
 | 	stw	r20, 80(sp) | 
 | 	stw	r21, 84(sp) | 
 | 	stw	r22, 88(sp) | 
 | 	stw	r23, 92(sp) | 
 | 	stw	r24, 96(sp) | 
 | 	stw	r25, 100(sp) | 
 | 	stw	r26, 104(sp) | 
 | 	stw	r27, 108(sp) | 
 | 	stw	r28, 112(sp) | 
 | 	stw	r29, 116(sp) | 
 | 	stw	r30, 120(sp) | 
 | 	stw	r31, 124(sp) | 
 | 	rdctl	et, estatus | 
 | 	stw	et, 128(sp) | 
 |  | 
 | 	/* If interrupts are disabled -- software interrupt */ | 
 | 	rdctl	et, estatus | 
 | 	andi	et, et, 1 | 
 | 	beq	et, r0, 0f | 
 |  | 
 | 	/* If no interrupts are pending -- software interrupt */ | 
 | 	rdctl	et, ipending | 
 | 	beq	et, r0, 0f | 
 |  | 
 | 	/* HARDWARE INTERRUPT: Call interrupt handler */ | 
 | 	movhi	r3, %hi(external_interrupt) | 
 | 	ori	r3, r3, %lo(external_interrupt) | 
 | 	mov	r4, sp		/* ptr to regs */ | 
 | 	callr	r3 | 
 |  | 
 | 	/* Return address fixup: execution resumes by re-issue of | 
 | 	 * interrupted instruction at ea-4 (ea == r29). Here we do | 
 | 	 * simple fixup to allow common exception return. | 
 | 	 */ | 
 | 	ldw	r3, 116(sp) | 
 | 	addi	r3, r3, -4 | 
 | 	stw	r3, 116(sp) | 
 | 	br	_exception_return | 
 |  | 
 | 0: | 
 | 	/* TRAP EXCEPTION */ | 
 | 	movhi	r3, %hi(OPC_TRAP) | 
 | 	ori	r3, r3, %lo(OPC_TRAP) | 
 | 	addi	r1, ea, -4 | 
 | 	ldw	r1, 0(r1) | 
 | 	bne	r1, r3, 1f | 
 | 	movhi	r3, %hi(trap_handler) | 
 | 	ori	r3, r3, %lo(trap_handler) | 
 | 	mov	r4, sp		/* ptr to regs */ | 
 | 	callr	r3 | 
 | 	br	_exception_return | 
 |  | 
 | 1: | 
 | 	/* UNIMPLEMENTED INSTRUCTION EXCEPTION */ | 
 | 	movhi	r3, %hi(soft_emulation) | 
 | 	ori	r3, r3, %lo(soft_emulation) | 
 | 	mov	r4, sp		/* ptr to regs */ | 
 | 	callr	r3 | 
 |  | 
 | 	/* Restore regsisters and return from exception*/ | 
 | _exception_return: | 
 | 	ldw	r1, 4(sp) | 
 | 	ldw	r2, 8(sp) | 
 | 	ldw	r3, 12(sp) | 
 | 	ldw	r4, 16(sp) | 
 | 	ldw	r5, 20(sp) | 
 | 	ldw	r6, 24(sp) | 
 | 	ldw	r7, 28(sp) | 
 | 	ldw	r8, 32(sp) | 
 | 	ldw	r9, 36(sp) | 
 | 	ldw	r10, 40(sp) | 
 | 	ldw	r11, 44(sp) | 
 | 	ldw	r12, 48(sp) | 
 | 	ldw	r13, 52(sp) | 
 | 	ldw	r14, 56(sp) | 
 | 	ldw	r15, 60(sp) | 
 | 	ldw	r16, 64(sp) | 
 | 	ldw	r17, 68(sp) | 
 | 	ldw	r19, 72(sp) | 
 | 	ldw	r19, 76(sp) | 
 | 	ldw	r20, 80(sp) | 
 | 	ldw	r21, 84(sp) | 
 | 	ldw	r22, 88(sp) | 
 | 	ldw	r23, 92(sp) | 
 | 	ldw	r24, 96(sp) | 
 | 	ldw	r25, 100(sp) | 
 | 	ldw	r26, 104(sp) | 
 | 	ldw	r27, 108(sp) | 
 | 	ldw	r28, 112(sp) | 
 | 	ldw	r29, 116(sp) | 
 | 	ldw	r30, 120(sp) | 
 | 	ldw	r31, 124(sp) | 
 | 	addi	sp, sp, (33*4) | 
 | 	eret | 
 | /*-------------------------------------------------------------*/ |