From 43dfd862514a62b909fa5211d3086ae64c087afd Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Markus=20Fr=C3=B6schle?= <mfro@mubf.de>
Date: Wed, 20 Nov 2013 05:52:32 +0000
Subject: [PATCH] start of rewrite of exceptions.S in C

---
 BaS_gcc/Makefile             |   1 +
 BaS_gcc/sources/exceptions.c | 162 +++++++++++++++++++++++++++++++++++
 2 files changed, 163 insertions(+)
 create mode 100644 BaS_gcc/sources/exceptions.c

diff --git a/BaS_gcc/Makefile b/BaS_gcc/Makefile
index ec44e19..ca5b0ff 100644
--- a/BaS_gcc/Makefile
+++ b/BaS_gcc/Makefile
@@ -61,6 +61,7 @@ BASFLASH_EXEC=basflash.$(EXE)
 CSRCS= \
 	$(SRCDIR)/sysinit.c \
 	$(SRCDIR)/init_fpga.c \
+	$(SRCDIR)/exceptions.c \
 	$(SRCDIR)/mmu.c \
 	$(SRCDIR)/fault_vectors.c \
 	$(SRCDIR)/interrupts.c \
diff --git a/BaS_gcc/sources/exceptions.c b/BaS_gcc/sources/exceptions.c
new file mode 100644
index 0000000..0c57d61
--- /dev/null
+++ b/BaS_gcc/sources/exceptions.c
@@ -0,0 +1,162 @@
+/*
+ * exceptions.c
+ *
+ * This file is part of BaS_gcc.
+ *
+ * BaS_gcc 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 3 of the License, or
+ * (at your option) any later version.
+ *
+ * BaS_gcc 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 BaS_gcc.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ * derived from original BaS assembler sources:
+ * Copyright 2010 - 2012 F. Aschwanden
+ * Copyright 2013        M. Froeschle
+ */
+
+#include <stdint.h>
+#include "bas_printf.h"
+#include "bas_string.h"
+
+#if MACHINE_FIREBEE
+#include "firebee.h"
+#elif MACHINE_M5484LITE
+#include "m5484l.h"
+#endif /* MACHINE_FIREBEE */
+
+
+#define DEBUG_EXC
+#ifdef DEBUG_EXC
+#define debug_printf(format, arg...) do { xprintf("DEBUG: " format "\r\n", ##arg); } while (0)
+#else
+#define debug_printf(format, arg...) do { ; } while (0)
+#endif /* DEBUG_EXC */
+
+inline uint32_t set_vbr(uint32_t value)
+{
+	extern uint32_t rt_vbr;
+	uint32_t ret = rt_vbr;
+
+	__asm__ __volatile__(
+		"movec		%[value],VBR\n\t"
+		: /* no output */
+		: [value] "r" (value)
+		: /* no clobber */
+	);
+	rt_vbr = value;
+
+	return ret;
+}
+
+void __attribute__((interrupt)) std_exception_handler()
+{
+}
+
+void __attribute__((interrupt)) reset_exception_handler()
+{
+}
+
+void __attribute__((interrupt)) access_exception_handler()
+{
+}
+
+void __attribute__((interrupt)) irq1_exception_handler()
+{
+}
+
+void __attribute__((interrupt)) irq2_exception_handler()
+{
+}
+
+void __attribute__((interrupt)) irq3_exception_handler()
+{
+}
+
+void __attribute__((interrupt)) irq4_exception_handler()
+{
+}
+
+void __attribute__((interrupt)) irq5_exception_handler()
+{
+}
+
+void __attribute__((interrupt)) irq6_exception_handler()
+{
+}
+
+void __attribute__((interrupt)) irq7_exception_handler()
+{
+}
+
+void vec_init(void)
+{
+	extern uint32_t _RAMBAR0[];	/* defined in linker script */
+	uint32_t *VBR = &_RAMBAR0[0];
+	extern uint32_t rt_mod;
+	extern uint32_t rt_ssp;
+	extern uint32_t rt_usp;
+	extern uint32_t rt_vbr;
+	int i;
+
+	rt_mod = -1;
+	rt_ssp = 0;
+	rt_usp = 0;
+	rt_vbr = 0;
+
+	set_vbr((uint32_t) VBR);
+
+	/*
+	 * set exception vectors
+	 */
+	for (i = 0; i < 256; i++)
+	{
+		VBR[i] = std_exception_handler;
+	}
+
+	VBR[0] = __SUP_SP;
+
+	VBR[1] = reset_exception_handler;
+	VBR[2] = access_exception_handler;
+
+#if MACHINE_FIREBEE		/* DIP switch only on FireBee */
+	if (DIP_SWITCH & (1 << 7))
+	{
+		/* TODO: protect mode */
+		return;
+	}
+#endif /* MACHINE_FIREBEE */
+
+	VBR[0X80] = xhdi_install;	/* trap #0 exception handler for BaS driver vectors */
+
+
+#if MACHINE_FIREBEE
+	/*
+	 * ACP interrupts 1-7 (generated by the FPGA on the FireBee)
+	 */
+ 	VBR[0X104] = (uint32_t) irq1_exception_handler;
+	VBR[0x108] = (uint32_t) irq2_exception_handler;
+	VBR[0x10c] = (uint32_t) irq3_exception_handler;
+	VBR[0x110] = (uint32_t) irq4_exception_handler;
+	VBR[0x114] = (uint32_t) irq5_exception_handler;
+	VBR[0x118] = (uint32_t) irq6_exception_handler;
+	VBR[0x11c] = (uint32_t) irq7_exception_handler;
+
+	/*
+	 * install PSC vectors (used for PIC communication on the FireBee
+	 */
+	VBR[INT_SOURCE_PSC3 + 64] = psc3_interrupt_handler;
+
+	/*
+	 * install timer vector (used for video page copy on the FireBee
+	 */
+	VBR[INT_SOURCE_GPT0 + 64] = gpt0_interrupt_handler;
+#endif /* MACHINE_FIREBEE */
+}
+