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-rw-r--r--arch/frv/kernel/debug-stub.c259
1 files changed, 259 insertions, 0 deletions
diff --git a/arch/frv/kernel/debug-stub.c b/arch/frv/kernel/debug-stub.c
new file mode 100644
index 000000000000..4761cc4b4a90
--- /dev/null
+++ b/arch/frv/kernel/debug-stub.c
@@ -0,0 +1,259 @@
+/* debug-stub.c: debug-mode stub
+ *
+ * Copyright (C) 2004 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@redhat.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.
+ */
+
+#include <linux/string.h>
+#include <linux/kernel.h>
+#include <linux/signal.h>
+#include <linux/sched.h>
+#include <linux/init.h>
+#include <linux/serial_reg.h>
+
+#include <asm/system.h>
+#include <asm/serial-regs.h>
+#include <asm/timer-regs.h>
+#include <asm/irc-regs.h>
+#include <asm/gdb-stub.h>
+#include "gdb-io.h"
+
+/* CPU board CON5 */
+#define __UART0(X) (*(volatile uint8_t *)(UART0_BASE + (UART_##X)))
+
+#define LSR_WAIT_FOR0(STATE) \
+do { \
+} while (!(__UART0(LSR) & UART_LSR_##STATE))
+
+#define FLOWCTL_QUERY0(LINE) ({ __UART0(MSR) & UART_MSR_##LINE; })
+#define FLOWCTL_CLEAR0(LINE) do { __UART0(MCR) &= ~UART_MCR_##LINE; } while (0)
+#define FLOWCTL_SET0(LINE) do { __UART0(MCR) |= UART_MCR_##LINE; } while (0)
+
+#define FLOWCTL_WAIT_FOR0(LINE) \
+do { \
+ gdbstub_do_rx(); \
+} while(!FLOWCTL_QUERY(LINE))
+
+static void __init debug_stub_init(void);
+
+extern asmlinkage void __break_hijack_kernel_event(void);
+extern asmlinkage void __break_hijack_kernel_event_breaks_here(void);
+
+/*****************************************************************************/
+/*
+ * debug mode handler stub
+ * - we come here with the CPU in debug mode and with exceptions disabled
+ * - handle debugging services for userspace
+ */
+asmlinkage void debug_stub(void)
+{
+ unsigned long hsr0;
+ int type = 0;
+
+ static u8 inited = 0;
+ if (!inited) {
+ debug_stub_init();
+ type = -1;
+ inited = 1;
+ }
+
+ hsr0 = __get_HSR(0);
+ if (hsr0 & HSR0_ETMD)
+ __set_HSR(0, hsr0 & ~HSR0_ETMD);
+
+ /* disable single stepping */
+ __debug_regs->dcr &= ~DCR_SE;
+
+ /* kernel mode can propose an exception be handled in debug mode by jumping to a special
+ * location */
+ if (__debug_frame->pc == (unsigned long) __break_hijack_kernel_event_breaks_here) {
+ /* replace the debug frame with the kernel frame and discard
+ * the top kernel context */
+ *__debug_frame = *__frame;
+ __frame = __debug_frame->next_frame;
+ __debug_regs->brr = (__debug_frame->tbr & TBR_TT) << 12;
+ __debug_regs->brr |= BRR_EB;
+ }
+
+ if (__debug_frame->pc == (unsigned long) __debug_bug_trap + 4) {
+ __debug_frame->pc = __debug_frame->lr;
+ type = __debug_frame->gr8;
+ }
+
+#ifdef CONFIG_GDBSTUB
+ gdbstub(type);
+#endif
+
+ if (hsr0 & HSR0_ETMD)
+ __set_HSR(0, __get_HSR(0) | HSR0_ETMD);
+
+} /* end debug_stub() */
+
+/*****************************************************************************/
+/*
+ * debug stub initialisation
+ */
+static void __init debug_stub_init(void)
+{
+ __set_IRR(6, 0xff000000); /* map ERRs to NMI */
+ __set_IITMR(1, 0x20000000); /* ERR0/1, UART0/1 IRQ detect levels */
+
+ asm volatile(" movgs gr0,ibar0 \n"
+ " movgs gr0,ibar1 \n"
+ " movgs gr0,ibar2 \n"
+ " movgs gr0,ibar3 \n"
+ " movgs gr0,dbar0 \n"
+ " movgs gr0,dbmr00 \n"
+ " movgs gr0,dbmr01 \n"
+ " movgs gr0,dbdr00 \n"
+ " movgs gr0,dbdr01 \n"
+ " movgs gr0,dbar1 \n"
+ " movgs gr0,dbmr10 \n"
+ " movgs gr0,dbmr11 \n"
+ " movgs gr0,dbdr10 \n"
+ " movgs gr0,dbdr11 \n"
+ );
+
+ /* deal with debugging stub initialisation and initial pause */
+ if (__debug_frame->pc == (unsigned long) __debug_stub_init_break)
+ __debug_frame->pc = (unsigned long) start_kernel;
+
+ /* enable the debug events we want to trap */
+ __debug_regs->dcr = DCR_EBE;
+
+#ifdef CONFIG_GDBSTUB
+ gdbstub_init();
+#endif
+
+ __clr_MASK_all();
+ __clr_MASK(15);
+ __clr_RC(15);
+
+} /* end debug_stub_init() */
+
+/*****************************************************************************/
+/*
+ * kernel "exit" trap for gdb stub
+ */
+void debug_stub_exit(int status)
+{
+
+#ifdef CONFIG_GDBSTUB
+ gdbstub_exit(status);
+#endif
+
+} /* end debug_stub_exit() */
+
+/*****************************************************************************/
+/*
+ * send string to serial port
+ */
+void debug_to_serial(const char *p, int n)
+{
+ char ch;
+
+ for (; n > 0; n--) {
+ ch = *p++;
+ FLOWCTL_SET0(DTR);
+ LSR_WAIT_FOR0(THRE);
+ // FLOWCTL_WAIT_FOR(CTS);
+
+ if (ch == 0x0a) {
+ __UART0(TX) = 0x0d;
+ mb();
+ LSR_WAIT_FOR0(THRE);
+ // FLOWCTL_WAIT_FOR(CTS);
+ }
+ __UART0(TX) = ch;
+ mb();
+
+ FLOWCTL_CLEAR0(DTR);
+ }
+
+} /* end debug_to_serial() */
+
+/*****************************************************************************/
+/*
+ * send string to serial port
+ */
+void debug_to_serial2(const char *fmt, ...)
+{
+ va_list va;
+ char buf[64];
+ int n;
+
+ va_start(va, fmt);
+ n = vsprintf(buf, fmt, va);
+ va_end(va);
+
+ debug_to_serial(buf, n);
+
+} /* end debug_to_serial2() */
+
+/*****************************************************************************/
+/*
+ * set up the ttyS0 serial port baud rate timers
+ */
+void __init console_set_baud(unsigned baud)
+{
+ unsigned value, high, low;
+ u8 lcr;
+
+ /* work out the divisor to give us the nearest higher baud rate */
+ value = __serial_clock_speed_HZ / 16 / baud;
+
+ /* determine the baud rate range */
+ high = __serial_clock_speed_HZ / 16 / value;
+ low = __serial_clock_speed_HZ / 16 / (value + 1);
+
+ /* pick the nearest bound */
+ if (low + (high - low) / 2 > baud)
+ value++;
+
+ lcr = __UART0(LCR);
+ __UART0(LCR) |= UART_LCR_DLAB;
+ mb();
+ __UART0(DLL) = value & 0xff;
+ __UART0(DLM) = (value >> 8) & 0xff;
+ mb();
+ __UART0(LCR) = lcr;
+ mb();
+
+} /* end console_set_baud() */
+
+/*****************************************************************************/
+/*
+ *
+ */
+int __init console_get_baud(void)
+{
+ unsigned value;
+ u8 lcr;
+
+ lcr = __UART0(LCR);
+ __UART0(LCR) |= UART_LCR_DLAB;
+ mb();
+ value = __UART0(DLM) << 8;
+ value |= __UART0(DLL);
+ __UART0(LCR) = lcr;
+ mb();
+
+ return value;
+} /* end console_get_baud() */
+
+/*****************************************************************************/
+/*
+ * display BUG() info
+ */
+#ifndef CONFIG_NO_KERNEL_MSG
+void __debug_bug_printk(const char *file, unsigned line)
+{
+ printk("kernel BUG at %s:%d!\n", file, line);
+
+} /* end __debug_bug_printk() */
+#endif