nios2: convert copy_exception_trampoline to use dm cpu data

Convert copy_exception_trampoline() to use dm cpu data.

Signed-off-by: Thomas Chou <thomas@wytron.com.tw>

arch/nios2/cpu/cpu.c

@@ -29,6 +29,27 @@ int do_reset(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
 	return 0;
 }
 
+/*
+ * COPY EXCEPTION TRAMPOLINE -- copy the tramp to the
+ * exception address. Define CONFIG_ROM_STUBS to prevent
+ * the copy (e.g. exception in flash or in other
+ * softare/firmware component).
+ */
+#ifndef CONFIG_ROM_STUBS
+static void copy_exception_trampoline(void)
+{
+	extern int _except_start, _except_end;
+	void *except_target = (void *)gd->arch.exception_addr;
+
+	if (&_except_start != except_target) {
+		memcpy(except_target, &_except_start,
+		       &_except_end - &_except_start);
+		flush_cache(gd->arch.exception_addr,
+			    &_except_end - &_except_start);
+	}
+}
+#endif
+
 int arch_cpu_init_dm(void)
 {
 	struct udevice *dev;
@@ -41,6 +62,9 @@ int arch_cpu_init_dm(void)
 		return -ENODEV;
 
 	gd->ram_size = CONFIG_SYS_SDRAM_SIZE;
+#ifndef CONFIG_ROM_STUBS
+	copy_exception_trampoline();
+#endif
 
 	return 0;
 }

arch/nios2/cpu/start.S

@@ -20,7 +20,7 @@
 
 	/* RESTART */
 	.text
-	.global _start
+	.global _start, _except_start, _except_end
 
 _start:
 	wrctl	status, r0		/* Disable interrupts */
@@ -99,29 +99,6 @@ _cur:	movhi	r5, %hi(_cur - _start)
 	jmp	r4
 _reloc:
 
-	/*
-	 * COPY EXCEPTION TRAMPOLINE -- copy the tramp to the
-	 * exception address. Define CONFIG_ROM_STUBS to prevent
-	 * the copy (e.g. exception in flash or in other
-	 * softare/firmware component).
-	 */
-#if !defined(CONFIG_ROM_STUBS)
-	movhi	r4, %hi(_except_start)
-	ori	r4, r4, %lo(_except_start)
-	movhi	r5, %hi(_except_end)
-	ori	r5, r5, %lo(_except_end)
-	movhi	r6, %hi(CONFIG_SYS_EXCEPTION_ADDR)
-	ori	r6, r6, %lo(CONFIG_SYS_EXCEPTION_ADDR)
-	beq	r4, r6, 7f	/* Skip if at proper addr */
-
-6:	ldwio	r7, 0(r4)
-	stwio	r7, 0(r6)
-	addi	r4, r4, 4
-	addi	r6, r6, 4
-	bne	r4, r5, 6b
-7:
-#endif
-
 	/* STACK INIT -- zero top two words for call back chain. */
 	movhi	sp, %hi(CONFIG_SYS_INIT_SP)
 	ori	sp, sp, %lo(CONFIG_SYS_INIT_SP)