1 files changed, 201 insertions, 0 deletions
diff --git a/libgloss/or1k/exceptions-asm.S b/libgloss/or1k/exceptions-asm.S
new file mode 100644
index 000000000..7248683f5
--- /dev/null
+++ b/libgloss/or1k/exceptions-asm.S
@@ -0,0 +1,201 @@
+/* exceptions-asm.S -- exception handling for OpenRISC 1000.
+ *
+ * Copyright (c) 2011, 2014 Authors
+ *
+ * Contributor Julius Baxter <juliusbaxter@gmail.com>
+ * Contributor Stefan Wallentowitz <stefan.wallentowitz@tum.de>
+ *
+ * The authors hereby grant permission to use, copy, modify, distribute,
+ * and license this software and its documentation for any purpose, provided
+ * that existing copyright notices are retained in all copies and that this
+ * notice is included verbatim in any distributions. No written agreement,
+ * license, or royalty fee is required for any of the authorized uses.
+ * Modifications to this software may be copyrighted by their authors
+ * and need not follow the licensing terms described here, provided that
+ * the new terms are clearly indicated on the first page of each file where
+ * they apply.
+ */
+
+#include "include/or1k-asm.h"
+#include "include/or1k-sprs.h"
+
+/* -------------------------------------------------------------------------- */
+/*!Generic exception handler function
+                                                                              */
+/* -------------------------------------------------------------------------- */
+// Warning - this must be the same as specified in crt0.S
+#define EXCEPTION_STACK_SIZE 128+128
+
+	.extern _or1k_exception_handler_table
+
+/* -------------------------------------------------------------------------- */
+/*!Function to call appropriate exception handler
+                                                                              */
+/* -------------------------------------------------------------------------- */
+	.section .text
+	.global	_or1k_exception_handler
+	.type	_or1k_exception_handler,@function
+
+	/*
+	r3 = address of exception vector
+	r4 = address where exception occurred
+	*/
+
+#define GPR_BUF_OFFSET(x) (x << 2)
+
+_or1k_exception_handler:
+	/* Store remainder of state (r3,r4 stored in vector entry)*/
+	l.sw	GPR_BUF_OFFSET(2)(r1),r2
+	l.sw	GPR_BUF_OFFSET(5)(r1),r5
+	l.sw	GPR_BUF_OFFSET(6)(r1),r6
+	l.sw	GPR_BUF_OFFSET(7)(r1),r7
+	l.sw	GPR_BUF_OFFSET(8)(r1),r8
+	l.sw	GPR_BUF_OFFSET(9)(r1),r9
+	l.sw	GPR_BUF_OFFSET(10)(r1),r10
+	l.sw	GPR_BUF_OFFSET(11)(r1),r11
+	l.sw	GPR_BUF_OFFSET(12)(r1),r12
+	l.sw	GPR_BUF_OFFSET(13)(r1),r13
+	l.sw	GPR_BUF_OFFSET(14)(r1),r14
+	l.sw	GPR_BUF_OFFSET(15)(r1),r15
+	l.sw	GPR_BUF_OFFSET(16)(r1),r16
+	l.sw	GPR_BUF_OFFSET(17)(r1),r17
+	l.sw	GPR_BUF_OFFSET(18)(r1),r18
+	l.sw	GPR_BUF_OFFSET(19)(r1),r19
+	l.sw	GPR_BUF_OFFSET(20)(r1),r20
+	l.sw	GPR_BUF_OFFSET(21)(r1),r21
+	l.sw	GPR_BUF_OFFSET(22)(r1),r22
+	l.sw	GPR_BUF_OFFSET(23)(r1),r23
+	l.sw	GPR_BUF_OFFSET(24)(r1),r24
+	l.sw	GPR_BUF_OFFSET(25)(r1),r25
+	l.sw	GPR_BUF_OFFSET(26)(r1),r26
+	l.sw	GPR_BUF_OFFSET(27)(r1),r27
+	l.sw	GPR_BUF_OFFSET(28)(r1),r28
+	l.sw	GPR_BUF_OFFSET(29)(r1),r29
+	l.sw	GPR_BUF_OFFSET(30)(r1),r30
+	l.sw	GPR_BUF_OFFSET(31)(r1),r31
+
+	/* Replace impure pointer for exception */
+	l.movhi	r20,hi(_or1k_exception_impure_ptr)
+	l.ori	r20,r20,lo(_or1k_exception_impure_ptr)
+#ifdef __OR1K_MULTICORE__
+	l.lwz	r20,0(r20)
+	l.mfspr	r22,r0,OR1K_SPR_SYS_COREID_ADDR
+	l.slli	r22,r22,2
+	l.add	r20,r20,r22
+#endif
+	l.lwz	r20,0(r20)
+
+	l.movhi	r21,hi(_or1k_current_impure_ptr)
+	l.ori	r21,r21,lo(_or1k_current_impure_ptr)
+#ifdef __OR1K_MULTICORE__
+	l.lwz	r21,0(r21)
+	l.add	r21,r21,r22
+#endif
+	l.sw	0(r21),r20
+
+	/* Determine offset in table of exception handler using r3*/
+	l.andi	r13,r3,0xff00
+	l.srli	r13,r13,6
+	/* Substract 2 words, as we have no vector at 0 and no reset handler */
+	l.addi	r13,r13,-8
+	/* r13 now contains offset in or1k_exception_handler_table for
+	   function
+	*/
+	/* Get or1k_exception_handler_table address */
+	l.movhi	r14,hi(_or1k_exception_handler_table)
+	l.ori	r14,r14,lo(_or1k_exception_handler_table)
+#ifdef __OR1K_MULTICORE__
+	/* Read the address of the array of cores */
+	/* r14 = (*or1k_exception_handler_table)  */
+	l.lwz	r14,0(r14)
+	/* Generate core offset in array (off = coreid*30*4 = coreid*120) */
+	/* r15 = coreid */
+	l.mfspr	r15,r0,OR1K_SPR_SYS_COREID_ADDR
+	/* r16 = coreid * 128 */
+	l.slli	r16,r15,7
+	/* r15 = coreid * 8 */
+	l.slli	r15,r15,3
+	/* r15 = coreid*128 - coreid*8 = coreid*120 = off */
+	l.sub	r15,r16,r15
+	/* r14 = (*or1k_exception_handler_table)[coreid] =  r14 + off */
+	l.add	r14,r14,r15
+#endif
+	/* r14 now contains base of exception handler table */
+	/* add offset of exception vector */
+	l.add	r14,r14,r13
+	/* load handler address from table */
+	l.lwz	r13, 0(r14)
+
+	/* Check to see if this handler has been set yet */
+	l.sfne	r13,r0
+	OR1K_DELAYED_NOP(OR1K_INST(l.bnf exception_exit))
+
+	/* Call exception handler, copy EPCR to r3 */
+	OR1K_DELAYED(
+		OR1K_INST(l.or   r3,r4,r4),
+		OR1K_INST(l.jalr r13)
+	)
+
+	/* Restore impure pointer */
+	l.movhi	r20,hi(_or1k_impure_ptr)
+	l.ori	r20,r20,lo(_or1k_impure_ptr)
+#ifdef __OR1K_MULTICORE__
+	l.lwz	r20,0(r20)
+	l.mfspr	r22,r0,OR1K_SPR_SYS_COREID_ADDR
+	l.slli	r22,r22,2
+	l.add	r20,r20,r22
+#endif
+	l.lwz	r20,0(r20)
+
+	l.movhi	r21,hi(_or1k_current_impure_ptr)
+	l.ori	r21,r21,lo(_or1k_current_impure_ptr)
+#ifdef __OR1K_MULTICORE__
+	l.lwz	r21,0(r21)
+	l.add	r21,r21,r22
+#endif
+	l.sw	0(r21),r20
+
+	/* Restore state */
+	l.lwz	r2,GPR_BUF_OFFSET(2)(r1)
+	l.lwz	r3,GPR_BUF_OFFSET(3)(r1)
+	l.lwz	r4,GPR_BUF_OFFSET(4)(r1)
+	l.lwz	r5,GPR_BUF_OFFSET(5)(r1)
+	l.lwz	r6,GPR_BUF_OFFSET(6)(r1)
+	l.lwz	r7,GPR_BUF_OFFSET(7)(r1)
+	l.lwz	r8,GPR_BUF_OFFSET(8)(r1)
+	l.lwz	r9,GPR_BUF_OFFSET(9)(r1)
+	l.lwz	r10,GPR_BUF_OFFSET(10)(r1)
+	l.lwz	r11,GPR_BUF_OFFSET(11)(r1)
+	l.lwz	r12,GPR_BUF_OFFSET(12)(r1)
+	l.lwz	r13,GPR_BUF_OFFSET(13)(r1)
+	l.lwz	r14,GPR_BUF_OFFSET(14)(r1)
+	l.lwz	r15,GPR_BUF_OFFSET(15)(r1)
+	l.lwz	r16,GPR_BUF_OFFSET(16)(r1)
+	l.lwz	r17,GPR_BUF_OFFSET(17)(r1)
+	l.lwz	r18,GPR_BUF_OFFSET(18)(r1)
+	l.lwz	r19,GPR_BUF_OFFSET(19)(r1)
+	l.lwz	r20,GPR_BUF_OFFSET(20)(r1)
+	l.lwz	r21,GPR_BUF_OFFSET(21)(r1)
+	l.lwz	r22,GPR_BUF_OFFSET(22)(r1)
+	l.lwz	r23,GPR_BUF_OFFSET(23)(r1)
+	l.lwz	r24,GPR_BUF_OFFSET(24)(r1)
+	l.lwz	r25,GPR_BUF_OFFSET(25)(r1)
+	l.lwz	r26,GPR_BUF_OFFSET(26)(r1)
+	l.lwz	r27,GPR_BUF_OFFSET(27)(r1)
+	l.lwz	r28,GPR_BUF_OFFSET(28)(r1)
+	l.lwz	r29,GPR_BUF_OFFSET(29)(r1)
+	l.lwz	r30,GPR_BUF_OFFSET(30)(r1)
+	l.lwz	r31,GPR_BUF_OFFSET(31)(r1)
+
+	// Restore original stack
+	l.lwz	r1,GPR_BUF_OFFSET(1)(r1)
+
+	l.rfe
+	l.nop
+
+exception_exit:
+	/* Exception handler not set, exit */
+	OR1K_DELAYED(
+		OR1K_INST(l.or  r3,r4,r4),
+		OR1K_INST(l.jal exit)
+	)