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Diffstat (limited to 'arch/mn10300/kernel/gdb-stub.c')
-rw-r--r--arch/mn10300/kernel/gdb-stub.c1947
1 files changed, 1947 insertions, 0 deletions
diff --git a/arch/mn10300/kernel/gdb-stub.c b/arch/mn10300/kernel/gdb-stub.c
new file mode 100644
index 00000000000..21891c71d54
--- /dev/null
+++ b/arch/mn10300/kernel/gdb-stub.c
@@ -0,0 +1,1947 @@
+/* MN10300 GDB stub
+ *
+ * Originally written by Glenn Engel, Lake Stevens Instrument Division
+ *
+ * Contributed by HP Systems
+ *
+ * Modified for SPARC by Stu Grossman, Cygnus Support.
+ *
+ * Modified for Linux/MIPS (and MIPS in general) by Andreas Busse
+ * Send complaints, suggestions etc. to <andy@waldorf-gmbh.de>
+ *
+ * Copyright (C) 1995 Andreas Busse
+ *
+ * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
+ * Modified for Linux/mn10300 by David Howells <dhowells@redhat.com>
+ */
+
+/*
+ * To enable debugger support, two things need to happen. One, a
+ * call to set_debug_traps() is necessary in order to allow any breakpoints
+ * or error conditions to be properly intercepted and reported to gdb.
+ * Two, a breakpoint needs to be generated to begin communication. This
+ * is most easily accomplished by a call to breakpoint(). Breakpoint()
+ * simulates a breakpoint by executing a BREAK instruction.
+ *
+ *
+ * The following gdb commands are supported:
+ *
+ * command function Return value
+ *
+ * g return the value of the CPU registers hex data or ENN
+ * G set the value of the CPU registers OK or ENN
+ *
+ * mAA..AA,LLLL Read LLLL bytes at address AA..AA hex data or ENN
+ * MAA..AA,LLLL: Write LLLL bytes at address AA.AA OK or ENN
+ *
+ * c Resume at current address SNN ( signal NN)
+ * cAA..AA Continue at address AA..AA SNN
+ *
+ * s Step one instruction SNN
+ * sAA..AA Step one instruction from AA..AA SNN
+ *
+ * k kill
+ *
+ * ? What was the last sigval ? SNN (signal NN)
+ *
+ * bBB..BB Set baud rate to BB..BB OK or BNN, then sets
+ * baud rate
+ *
+ * All commands and responses are sent with a packet which includes a
+ * checksum. A packet consists of
+ *
+ * $<packet info>#<checksum>.
+ *
+ * where
+ * <packet info> :: <characters representing the command or response>
+ * <checksum> :: < two hex digits computed as modulo 256 sum of <packetinfo>>
+ *
+ * When a packet is received, it is first acknowledged with either '+' or '-'.
+ * '+' indicates a successful transfer. '-' indicates a failed transfer.
+ *
+ * Example:
+ *
+ * Host: Reply:
+ * $m0,10#2a +$00010203040506070809101112131415#42
+ *
+ *
+ * ==============
+ * MORE EXAMPLES:
+ * ==============
+ *
+ * For reference -- the following are the steps that one
+ * company took (RidgeRun Inc) to get remote gdb debugging
+ * going. In this scenario the host machine was a PC and the
+ * target platform was a Galileo EVB64120A MIPS evaluation
+ * board.
+ *
+ * Step 1:
+ * First download gdb-5.0.tar.gz from the internet.
+ * and then build/install the package.
+ *
+ * Example:
+ * $ tar zxf gdb-5.0.tar.gz
+ * $ cd gdb-5.0
+ * $ ./configure --target=am33_2.0-linux-gnu
+ * $ make
+ * $ install
+ * am33_2.0-linux-gnu-gdb
+ *
+ * Step 2:
+ * Configure linux for remote debugging and build it.
+ *
+ * Example:
+ * $ cd ~/linux
+ * $ make menuconfig <go to "Kernel Hacking" and turn on remote debugging>
+ * $ make dep; make vmlinux
+ *
+ * Step 3:
+ * Download the kernel to the remote target and start
+ * the kernel running. It will promptly halt and wait
+ * for the host gdb session to connect. It does this
+ * since the "Kernel Hacking" option has defined
+ * CONFIG_REMOTE_DEBUG which in turn enables your calls
+ * to:
+ * set_debug_traps();
+ * breakpoint();
+ *
+ * Step 4:
+ * Start the gdb session on the host.
+ *
+ * Example:
+ * $ am33_2.0-linux-gnu-gdb vmlinux
+ * (gdb) set remotebaud 115200
+ * (gdb) target remote /dev/ttyS1
+ * ...at this point you are connected to
+ * the remote target and can use gdb
+ * in the normal fasion. Setting
+ * breakpoints, single stepping,
+ * printing variables, etc.
+ *
+ */
+
+#include <linux/string.h>
+#include <linux/kernel.h>
+#include <linux/signal.h>
+#include <linux/sched.h>
+#include <linux/mm.h>
+#include <linux/console.h>
+#include <linux/init.h>
+#include <linux/bug.h>
+
+#include <asm/pgtable.h>
+#include <asm/system.h>
+#include <asm/gdb-stub.h>
+#include <asm/exceptions.h>
+#include <asm/cacheflush.h>
+#include <asm/serial-regs.h>
+#include <asm/busctl-regs.h>
+#include <asm/unit/leds.h>
+#include <asm/unit/serial.h>
+
+/* define to use F7F7 rather than FF which is subverted by JTAG debugger */
+#undef GDBSTUB_USE_F7F7_AS_BREAKPOINT
+
+/*
+ * BUFMAX defines the maximum number of characters in inbound/outbound buffers
+ * at least NUMREGBYTES*2 are needed for register packets
+ */
+#define BUFMAX 2048
+
+static const char gdbstub_banner[] =
+ "Linux/MN10300 GDB Stub (c) RedHat 2007\n";
+
+u8 gdbstub_rx_buffer[PAGE_SIZE] __attribute__((aligned(PAGE_SIZE)));
+u32 gdbstub_rx_inp;
+u32 gdbstub_rx_outp;
+u8 gdbstub_busy;
+u8 gdbstub_rx_overflow;
+u8 gdbstub_rx_unget;
+
+static u8 gdbstub_flush_caches;
+static char input_buffer[BUFMAX];
+static char output_buffer[BUFMAX];
+static char trans_buffer[BUFMAX];
+
+static const char hexchars[] = "0123456789abcdef";
+
+struct gdbstub_bkpt {
+ u8 *addr; /* address of breakpoint */
+ u8 len; /* size of breakpoint */
+ u8 origbytes[7]; /* original bytes */
+};
+
+static struct gdbstub_bkpt gdbstub_bkpts[256];
+
+/*
+ * local prototypes
+ */
+static void getpacket(char *buffer);
+static int putpacket(char *buffer);
+static int computeSignal(enum exception_code excep);
+static int hex(unsigned char ch);
+static int hexToInt(char **ptr, int *intValue);
+static unsigned char *mem2hex(const void *mem, char *buf, int count,
+ int may_fault);
+static const char *hex2mem(const char *buf, void *_mem, int count,
+ int may_fault);
+
+/*
+ * Convert ch from a hex digit to an int
+ */
+static int hex(unsigned char ch)
+{
+ if (ch >= 'a' && ch <= 'f')
+ return ch - 'a' + 10;
+ if (ch >= '0' && ch <= '9')
+ return ch - '0';
+ if (ch >= 'A' && ch <= 'F')
+ return ch - 'A' + 10;
+ return -1;
+}
+
+#ifdef CONFIG_GDBSTUB_DEBUGGING
+
+void debug_to_serial(const char *p, int n)
+{
+ __debug_to_serial(p, n);
+ /* gdbstub_console_write(NULL, p, n); */
+}
+
+void gdbstub_printk(const char *fmt, ...)
+{
+ va_list args;
+ int len;
+
+ /* Emit the output into the temporary buffer */
+ va_start(args, fmt);
+ len = vsnprintf(trans_buffer, sizeof(trans_buffer), fmt, args);
+ va_end(args);
+ debug_to_serial(trans_buffer, len);
+}
+
+#endif
+
+static inline char *gdbstub_strcpy(char *dst, const char *src)
+{
+ int loop = 0;
+ while ((dst[loop] = src[loop]))
+ loop++;
+ return dst;
+}
+
+/*
+ * scan for the sequence $<data>#<checksum>
+ */
+static void getpacket(char *buffer)
+{
+ unsigned char checksum;
+ unsigned char xmitcsum;
+ unsigned char ch;
+ int count, i, ret, error;
+
+ for (;;) {
+ /*
+ * wait around for the start character,
+ * ignore all other characters
+ */
+ do {
+ gdbstub_io_rx_char(&ch, 0);
+ } while (ch != '$');
+
+ checksum = 0;
+ xmitcsum = -1;
+ count = 0;
+ error = 0;
+
+ /*
+ * now, read until a # or end of buffer is found
+ */
+ while (count < BUFMAX) {
+ ret = gdbstub_io_rx_char(&ch, 0);
+ if (ret < 0)
+ error = ret;
+
+ if (ch == '#')
+ break;
+ checksum += ch;
+ buffer[count] = ch;
+ count++;
+ }
+
+ if (error == -EIO) {
+ gdbstub_proto("### GDB Rx Error - Skipping packet"
+ " ###\n");
+ gdbstub_proto("### GDB Tx NAK\n");
+ gdbstub_io_tx_char('-');
+ continue;
+ }
+
+ if (count >= BUFMAX || error)
+ continue;
+
+ buffer[count] = 0;
+
+ /* read the checksum */
+ ret = gdbstub_io_rx_char(&ch, 0);
+ if (ret < 0)
+ error = ret;
+ xmitcsum = hex(ch) << 4;
+
+ ret = gdbstub_io_rx_char(&ch, 0);
+ if (ret < 0)
+ error = ret;
+ xmitcsum |= hex(ch);
+
+ if (error) {
+ if (error == -EIO)
+ gdbstub_io("### GDB Rx Error -"
+ " Skipping packet\n");
+ gdbstub_io("### GDB Tx NAK\n");
+ gdbstub_io_tx_char('-');
+ continue;
+ }
+
+ /* check the checksum */
+ if (checksum != xmitcsum) {
+ gdbstub_io("### GDB Tx NAK\n");
+ gdbstub_io_tx_char('-'); /* failed checksum */
+ continue;
+ }
+
+ gdbstub_proto("### GDB Rx '$%s#%02x' ###\n", buffer, checksum);
+ gdbstub_io("### GDB Tx ACK\n");
+ gdbstub_io_tx_char('+'); /* successful transfer */
+
+ /*
+ * if a sequence char is present,
+ * reply the sequence ID
+ */
+ if (buffer[2] == ':') {
+ gdbstub_io_tx_char(buffer[0]);
+ gdbstub_io_tx_char(buffer[1]);
+
+ /*
+ * remove sequence chars from buffer
+ */
+ count = 0;
+ while (buffer[count])
+ count++;
+ for (i = 3; i <= count; i++)
+ buffer[i - 3] = buffer[i];
+ }
+
+ break;
+ }
+}
+
+/*
+ * send the packet in buffer.
+ * - return 0 if successfully ACK'd
+ * - return 1 if abandoned due to new incoming packet
+ */
+static int putpacket(char *buffer)
+{
+ unsigned char checksum;
+ unsigned char ch;
+ int count;
+
+ /*
+ * $<packet info>#<checksum>.
+ */
+ gdbstub_proto("### GDB Tx $'%s'#?? ###\n", buffer);
+
+ do {
+ gdbstub_io_tx_char('$');
+ checksum = 0;
+ count = 0;
+
+ while ((ch = buffer[count]) != 0) {
+ gdbstub_io_tx_char(ch);
+ checksum += ch;
+ count += 1;
+ }
+
+ gdbstub_io_tx_char('#');
+ gdbstub_io_tx_char(hexchars[checksum >> 4]);
+ gdbstub_io_tx_char(hexchars[checksum & 0xf]);
+
+ } while (gdbstub_io_rx_char(&ch, 0),
+ ch == '-' && (gdbstub_io("### GDB Rx NAK\n"), 0),
+ ch != '-' && ch != '+' &&
+ (gdbstub_io("### GDB Rx ??? %02x\n", ch), 0),
+ ch != '+' && ch != '$');
+
+ if (ch == '+') {
+ gdbstub_io("### GDB Rx ACK\n");
+ return 0;
+ }
+
+ gdbstub_io("### GDB Tx Abandoned\n");
+ gdbstub_rx_unget = ch;
+ return 1;
+}
+
+/*
+ * While we find nice hex chars, build an int.
+ * Return number of chars processed.
+ */
+static int hexToInt(char **ptr, int *intValue)
+{
+ int numChars = 0;
+ int hexValue;
+
+ *intValue = 0;
+
+ while (**ptr) {
+ hexValue = hex(**ptr);
+ if (hexValue < 0)
+ break;
+
+ *intValue = (*intValue << 4) | hexValue;
+ numChars++;
+
+ (*ptr)++;
+ }
+
+ return (numChars);
+}
+
+/*
+ * We single-step by setting breakpoints. When an exception
+ * is handled, we need to restore the instructions hoisted
+ * when the breakpoints were set.
+ *
+ * This is where we save the original instructions.
+ */
+static struct gdb_bp_save {
+ u8 *addr;
+ u8 opcode[2];
+} step_bp[2];
+
+static const unsigned char gdbstub_insn_sizes[256] =
+{
+ /* 1 2 3 4 5 6 7 8 9 a b c d e f */
+ 1, 3, 3, 3, 1, 3, 3, 3, 1, 3, 3, 3, 1, 3, 3, 3, /* 0 */
+ 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, /* 1 */
+ 2, 2, 2, 2, 3, 3, 3, 3, 2, 2, 2, 2, 3, 3, 3, 3, /* 2 */
+ 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 1, 1, 1, 1, /* 3 */
+ 1, 1, 2, 2, 1, 1, 2, 2, 1, 1, 2, 2, 1, 1, 2, 2, /* 4 */
+ 1, 1, 1, 1, 1, 1, 1, 1, 2, 2, 2, 2, 2, 2, 2, 2, /* 5 */
+ 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, /* 6 */
+ 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, /* 7 */
+ 2, 1, 1, 1, 1, 2, 1, 1, 1, 1, 2, 1, 1, 1, 1, 2, /* 8 */
+ 2, 1, 1, 1, 1, 2, 1, 1, 1, 1, 2, 1, 1, 1, 1, 2, /* 9 */
+ 2, 1, 1, 1, 1, 2, 1, 1, 1, 1, 2, 1, 1, 1, 1, 2, /* a */
+ 2, 1, 1, 1, 1, 2, 1, 1, 1, 1, 2, 1, 1, 1, 1, 2, /* b */
+ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 2, 2, /* c */
+ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, /* d */
+ 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, /* e */
+ 0, 2, 2, 2, 2, 2, 2, 4, 0, 3, 0, 4, 0, 6, 7, 1 /* f */
+};
+
+static int __gdbstub_mark_bp(u8 *addr, int ix)
+{
+ if (addr < (u8 *) 0x70000000UL)
+ return 0;
+ /* 70000000-7fffffff: vmalloc area */
+ if (addr < (u8 *) 0x80000000UL)
+ goto okay;
+ if (addr < (u8 *) 0x8c000000UL)
+ return 0;
+ /* 8c000000-93ffffff: SRAM, SDRAM */
+ if (addr < (u8 *) 0x94000000UL)
+ goto okay;
+ return 0;
+
+okay:
+ if (gdbstub_read_byte(addr + 0, &step_bp[ix].opcode[0]) < 0 ||
+ gdbstub_read_byte(addr + 1, &step_bp[ix].opcode[1]) < 0)
+ return 0;
+
+ step_bp[ix].addr = addr;
+ return 1;
+}
+
+static inline void __gdbstub_restore_bp(void)
+{
+#ifdef GDBSTUB_USE_F7F7_AS_BREAKPOINT
+ if (step_bp[0].addr) {
+ gdbstub_write_byte(step_bp[0].opcode[0], step_bp[0].addr + 0);
+ gdbstub_write_byte(step_bp[0].opcode[1], step_bp[0].addr + 1);
+ }
+ if (step_bp[1].addr) {
+ gdbstub_write_byte(step_bp[1].opcode[0], step_bp[1].addr + 0);
+ gdbstub_write_byte(step_bp[1].opcode[1], step_bp[1].addr + 1);
+ }
+#else
+ if (step_bp[0].addr)
+ gdbstub_write_byte(step_bp[0].opcode[0], step_bp[0].addr + 0);
+ if (step_bp[1].addr)
+ gdbstub_write_byte(step_bp[1].opcode[0], step_bp[1].addr + 0);
+#endif
+
+ gdbstub_flush_caches = 1;
+
+ step_bp[0].addr = NULL;
+ step_bp[0].opcode[0] = 0;
+ step_bp[0].opcode[1] = 0;
+ step_bp[1].addr = NULL;
+ step_bp[1].opcode[0] = 0;
+ step_bp[1].opcode[1] = 0;
+}
+
+/*
+ * emulate single stepping by means of breakpoint instructions
+ */
+static int gdbstub_single_step(struct pt_regs *regs)
+{
+ unsigned size;
+ uint32_t x;
+ uint8_t cur, *pc, *sp;
+
+ step_bp[0].addr = NULL;
+ step_bp[0].opcode[0] = 0;
+ step_bp[0].opcode[1] = 0;
+ step_bp[1].addr = NULL;
+ step_bp[1].opcode[0] = 0;
+ step_bp[1].opcode[1] = 0;
+ x = 0;
+
+ pc = (u8 *) regs->pc;
+ sp = (u8 *) (regs + 1);
+ if (gdbstub_read_byte(pc, &cur) < 0)
+ return -EFAULT;
+
+ gdbstub_bkpt("Single Step from %p { %02x }\n", pc, cur);
+
+ gdbstub_flush_caches = 1;
+
+ size = gdbstub_insn_sizes[cur];
+ if (size > 0) {
+ if (!__gdbstub_mark_bp(pc + size, 0))
+ goto fault;
+ } else {
+ switch (cur) {
+ /* Bxx (d8,PC) */
+ case 0xc0:
+ case 0xc1:
+ case 0xc2:
+ case 0xc3:
+ case 0xc4:
+ case 0xc5:
+ case 0xc6:
+ case 0xc7:
+ case 0xc8:
+ case 0xc9:
+ case 0xca:
+ if (gdbstub_read_byte(pc + 1, (u8 *) &x) < 0)
+ goto fault;
+ if (!__gdbstub_mark_bp(pc + 2, 0))
+ goto fault;
+ if ((x < 0 || x > 2) &&
+ !__gdbstub_mark_bp(pc + (s8) x, 1))
+ goto fault;
+ break;
+
+ /* LXX (d8,PC) */
+ case 0xd0:
+ case 0xd1:
+ case 0xd2:
+ case 0xd3:
+ case 0xd4:
+ case 0xd5:
+ case 0xd6:
+ case 0xd7:
+ case 0xd8:
+ case 0xd9:
+ case 0xda:
+ if (!__gdbstub_mark_bp(pc + 1, 0))
+ goto fault;
+ if (regs->pc != regs->lar &&
+ !__gdbstub_mark_bp((u8 *) regs->lar, 1))
+ goto fault;
+ break;
+
+ /* SETLB - loads the next for bytes into the LIR
+ * register */
+ case 0xdb:
+ if (!__gdbstub_mark_bp(pc + 1, 0))
+ goto fault;
+ break;
+
+ /* JMP (d16,PC) or CALL (d16,PC) */
+ case 0xcc:
+ case 0xcd:
+ if (gdbstub_read_byte(pc + 1, ((u8 *) &x) + 0) < 0 ||
+ gdbstub_read_byte(pc + 2, ((u8 *) &x) + 1) < 0)
+ goto fault;
+ if (!__gdbstub_mark_bp(pc + (s16) x, 0))
+ goto fault;
+ break;
+
+ /* JMP (d32,PC) or CALL (d32,PC) */
+ case 0xdc:
+ case 0xdd:
+ if (gdbstub_read_byte(pc + 1, ((u8 *) &x) + 0) < 0 ||
+ gdbstub_read_byte(pc + 2, ((u8 *) &x) + 1) < 0 ||
+ gdbstub_read_byte(pc + 3, ((u8 *) &x) + 2) < 0 ||
+ gdbstub_read_byte(pc + 4, ((u8 *) &x) + 3) < 0)
+ goto fault;
+ if (!__gdbstub_mark_bp(pc + (s32) x, 0))
+ goto fault;
+ break;
+
+ /* RETF */
+ case 0xde:
+ if (!__gdbstub_mark_bp((u8 *) regs->mdr, 0))
+ goto fault;
+ break;
+
+ /* RET */
+ case 0xdf:
+ if (gdbstub_read_byte(pc + 2, (u8 *) &x) < 0)
+ goto fault;
+ sp += (s8)x;
+ if (gdbstub_read_byte(sp + 0, ((u8 *) &x) + 0) < 0 ||
+ gdbstub_read_byte(sp + 1, ((u8 *) &x) + 1) < 0 ||
+ gdbstub_read_byte(sp + 2, ((u8 *) &x) + 2) < 0 ||
+ gdbstub_read_byte(sp + 3, ((u8 *) &x) + 3) < 0)
+ goto fault;
+ if (!__gdbstub_mark_bp((u8 *) x, 0))
+ goto fault;
+ break;
+
+ case 0xf0:
+ if (gdbstub_read_byte(pc + 1, &cur) < 0)
+ goto fault;
+
+ if (cur >= 0xf0 && cur <= 0xf7) {
+ /* JMP (An) / CALLS (An) */
+ switch (cur & 3) {
+ case 0: x = regs->a0; break;
+ case 1: x = regs->a1; break;
+ case 2: x = regs->a2; break;
+ case 3: x = regs->a3; break;
+ }
+ if (!__gdbstub_mark_bp((u8 *) x, 0))
+ goto fault;
+ } else if (cur == 0xfc) {
+ /* RETS */
+ if (gdbstub_read_byte(
+ sp + 0, ((u8 *) &x) + 0) < 0 ||
+ gdbstub_read_byte(
+ sp + 1, ((u8 *) &x) + 1) < 0 ||
+ gdbstub_read_byte(
+ sp + 2, ((u8 *) &x) + 2) < 0 ||
+ gdbstub_read_byte(
+ sp + 3, ((u8 *) &x) + 3) < 0)
+ goto fault;
+ if (!__gdbstub_mark_bp((u8 *) x, 0))
+ goto fault;
+ } else if (cur == 0xfd) {
+ /* RTI */
+ if (gdbstub_read_byte(
+ sp + 4, ((u8 *) &x) + 0) < 0 ||
+ gdbstub_read_byte(
+ sp + 5, ((u8 *) &x) + 1) < 0 ||
+ gdbstub_read_byte(
+ sp + 6, ((u8 *) &x) + 2) < 0 ||
+ gdbstub_read_byte(
+ sp + 7, ((u8 *) &x) + 3) < 0)
+ goto fault;
+ if (!__gdbstub_mark_bp((u8 *) x, 0))
+ goto fault;
+ } else {
+ if (!__gdbstub_mark_bp(pc + 2, 0))
+ goto fault;
+ }
+
+ break;
+
+ /* potential 3-byte conditional branches */
+ case 0xf8:
+ if (gdbstub_read_byte(pc + 1, &cur) < 0)
+ goto fault;
+ if (!__gdbstub_mark_bp(pc + 3, 0))
+ goto fault;
+
+ if (cur >= 0xe8 && cur <= 0xeb) {
+ if (gdbstub_read_byte(
+ pc + 2, ((u8 *) &x) + 0) < 0)
+ goto fault;
+ if ((x < 0 || x > 3) &&
+ !__gdbstub_mark_bp(pc + (s8) x, 1))
+ goto fault;
+ }
+ break;
+
+ case 0xfa:
+ if (gdbstub_read_byte(pc + 1, &cur) < 0)
+ goto fault;
+
+ if (cur == 0xff) {
+ /* CALLS (d16,PC) */
+ if (gdbstub_read_byte(
+ pc + 2, ((u8 *) &x) + 0) < 0 ||
+ gdbstub_read_byte(
+ pc + 3, ((u8 *) &x) + 1) < 0)
+ goto fault;
+ if (!__gdbstub_mark_bp(pc + (s16) x, 0))
+ goto fault;
+ } else {
+ if (!__gdbstub_mark_bp(pc + 4, 0))
+ goto fault;
+ }
+ break;
+
+ case 0xfc:
+ if (gdbstub_read_byte(pc + 1, &cur) < 0)
+ goto fault;
+ if (cur == 0xff) {
+ /* CALLS (d32,PC) */
+ if (gdbstub_read_byte(
+ pc + 2, ((u8 *) &x) + 0) < 0 ||
+ gdbstub_read_byte(
+ pc + 3, ((u8 *) &x) + 1) < 0 ||
+ gdbstub_read_byte(
+ pc + 4, ((u8 *) &x) + 2) < 0 ||
+ gdbstub_read_byte(
+ pc + 5, ((u8 *) &x) + 3) < 0)
+ goto fault;
+ if (!__gdbstub_mark_bp(
+ pc + (s32) x, 0))
+ goto fault;
+ } else {
+ if (!__gdbstub_mark_bp(
+ pc + 6, 0))
+ goto fault;
+ }
+ break;
+
+ }
+ }
+
+ gdbstub_bkpt("Step: %02x at %p; %02x at %p\n",
+ step_bp[0].opcode[0], step_bp[0].addr,
+ step_bp[1].opcode[0], step_bp[1].addr);
+
+ if (step_bp[0].addr) {
+#ifdef GDBSTUB_USE_F7F7_AS_BREAKPOINT
+ if (gdbstub_write_byte(0xF7, step_bp[0].addr + 0) < 0 ||
+ gdbstub_write_byte(0xF7, step_bp[0].addr + 1) < 0)
+ goto fault;
+#else
+ if (gdbstub_write_byte(0xFF, step_bp[0].addr + 0) < 0)
+ goto fault;
+#endif
+ }
+
+ if (step_bp[1].addr) {
+#ifdef GDBSTUB_USE_F7F7_AS_BREAKPOINT
+ if (gdbstub_write_byte(0xF7, step_bp[1].addr + 0) < 0 ||
+ gdbstub_write_byte(0xF7, step_bp[1].addr + 1) < 0)
+ goto fault;
+#else
+ if (gdbstub_write_byte(0xFF, step_bp[1].addr + 0) < 0)
+ goto fault;
+#endif
+ }
+
+ return 0;
+
+ fault:
+ /* uh-oh - silly address alert, try and restore things */
+ __gdbstub_restore_bp();
+ return -EFAULT;
+}
+
+#ifdef CONFIG_GDBSTUB_CONSOLE
+
+void gdbstub_console_write(struct console *con, const char *p, unsigned n)
+{
+ static const char gdbstub_cr[] = { 0x0d };
+ char outbuf[26];
+ int qty;
+ u8 busy;
+
+ busy = gdbstub_busy;
+ gdbstub_busy = 1;
+
+ outbuf[0] = 'O';
+
+ while (n > 0) {
+ qty = 1;
+
+ while (n > 0 && qty < 20) {
+ mem2hex(p, outbuf + qty, 2, 0);
+ qty += 2;
+ if (*p == 0x0a) {
+ mem2hex(gdbstub_cr, outbuf + qty, 2, 0);
+ qty += 2;
+ }
+ p++;
+ n--;
+ }
+
+ outbuf[qty] = 0;
+ putpacket(outbuf);
+ }
+
+ gdbstub_busy = busy;
+}
+
+static kdev_t gdbstub_console_dev(struct console *con)
+{
+ return MKDEV(1, 3); /* /dev/null */
+}
+
+static struct console gdbstub_console = {
+ .name = "gdb",
+ .write = gdbstub_console_write,
+ .device = gdbstub_console_dev,
+ .flags = CON_PRINTBUFFER,
+ .index = -1,
+};
+
+#endif
+
+/*
+ * Convert the memory pointed to by mem into hex, placing result in buf.
+ * - if successful, return a pointer to the last char put in buf (NUL)
+ * - in case of mem fault, return NULL
+ * may_fault is non-zero if we are reading from arbitrary memory, but is
+ * currently not used.
+ */
+static
+unsigned char *mem2hex(const void *_mem, char *buf, int count, int may_fault)
+{
+ const u8 *mem = _mem;
+ u8 ch[4];
+
+ if ((u32) mem & 1 && count >= 1) {
+ if (gdbstub_read_byte(mem, ch) != 0)
+ return 0;
+ *buf++ = hexchars[ch[0] >> 4];
+ *buf++ = hexchars[ch[0] & 0xf];
+ mem++;
+ count--;
+ }
+
+ if ((u32) mem & 3 && count >= 2) {
+ if (gdbstub_read_word(mem, ch) != 0)
+ return 0;
+ *buf++ = hexchars[ch[0] >> 4];
+ *buf++ = hexchars[ch[0] & 0xf];
+ *buf++ = hexchars[ch[1] >> 4];
+ *buf++ = hexchars[ch[1] & 0xf];
+ mem += 2;
+ count -= 2;
+ }
+
+ while (count >= 4) {
+ if (gdbstub_read_dword(mem, ch) != 0)
+ return 0;
+ *buf++ = hexchars[ch[0] >> 4];
+ *buf++ = hexchars[ch[0] & 0xf];
+ *buf++ = hexchars[ch[1] >> 4];
+ *buf++ = hexchars[ch[1] & 0xf];
+ *buf++ = hexchars[ch[2] >> 4];
+ *buf++ = hexchars[ch[2] & 0xf];
+ *buf++ = hexchars[ch[3] >> 4];
+ *buf++ = hexchars[ch[3] & 0xf];
+ mem += 4;
+ count -= 4;
+ }
+
+ if (count >= 2) {
+ if (gdbstub_read_word(mem, ch) != 0)
+ return 0;
+ *buf++ = hexchars[ch[0] >> 4];
+ *buf++ = hexchars[ch[0] & 0xf];
+ *buf++ = hexchars[ch[1] >> 4];
+ *buf++ = hexchars[ch[1] & 0xf];
+ mem += 2;
+ count -= 2;
+ }
+
+ if (count >= 1) {
+ if (gdbstub_read_byte(mem, ch) != 0)
+ return 0;
+ *buf++ = hexchars[ch[0] >> 4];
+ *buf++ = hexchars[ch[0] & 0xf];
+ }
+
+ *buf = 0;
+ return buf;
+}
+
+/*
+ * convert the hex array pointed to by buf into binary to be placed in mem
+ * return a pointer to the character AFTER the last byte written
+ * may_fault is non-zero if we are reading from arbitrary memory, but is
+ * currently not used.
+ */
+static
+const char *hex2mem(const char *buf, void *_mem, int count, int may_fault)
+{
+ u8 *mem = _mem;
+ union {
+ u32 val;
+ u8 b[4];
+ } ch;
+
+ if ((u32) mem & 1 && count >= 1) {
+ ch.b[0] = hex(*buf++) << 4;
+ ch.b[0] |= hex(*buf++);
+ if (gdbstub_write_byte(ch.val, mem) != 0)
+ return 0;
+ mem++;
+ count--;
+ }
+
+ if ((u32) mem & 3 && count >= 2) {
+ ch.b[0] = hex(*buf++) << 4;
+ ch.b[0] |= hex(*buf++);
+ ch.b[1] = hex(*buf++) << 4;
+ ch.b[1] |= hex(*buf++);
+ if (gdbstub_write_word(ch.val, mem) != 0)
+ return 0;
+ mem += 2;
+ count -= 2;
+ }
+
+ while (count >= 4) {
+ ch.b[0] = hex(*buf++) << 4;
+ ch.b[0] |= hex(*buf++);
+ ch.b[1] = hex(*buf++) << 4;
+ ch.b[1] |= hex(*buf++);
+ ch.b[2] = hex(*buf++) << 4;
+ ch.b[2] |= hex(*buf++);
+ ch.b[3] = hex(*buf++) << 4;
+ ch.b[3] |= hex(*buf++);
+ if (gdbstub_write_dword(ch.val, mem) != 0)
+ return 0;
+ mem += 4;
+ count -= 4;
+ }
+
+ if (count >= 2) {
+ ch.b[0] = hex(*buf++) << 4;
+ ch.b[0] |= hex(*buf++);
+ ch.b[1] = hex(*buf++) << 4;
+ ch.b[1] |= hex(*buf++);
+ if (gdbstub_write_word(ch.val, mem) != 0)
+ return 0;
+ mem += 2;
+ count -= 2;
+ }
+
+ if (count >= 1) {
+ ch.b[0] = hex(*buf++) << 4;
+ ch.b[0] |= hex(*buf++);
+ if (gdbstub_write_byte(ch.val, mem) != 0)
+ return 0;
+ }
+
+ return buf;
+}
+
+/*
+ * This table contains the mapping between MN10300 exception codes, and
+ * signals, which are primarily what GDB understands. It also indicates
+ * which hardware traps we need to commandeer when initializing the stub.
+ */
+static const struct excep_to_sig_map {
+ enum exception_code excep; /* MN10300 exception code */
+ unsigned char signo; /* Signal that we map this into */
+} excep_to_sig_map[] = {
+ { EXCEP_ITLBMISS, SIGSEGV },
+ { EXCEP_DTLBMISS, SIGSEGV },
+ { EXCEP_TRAP, SIGTRAP },
+ { EXCEP_ISTEP, SIGTRAP },
+ { EXCEP_IBREAK, SIGTRAP },
+ { EXCEP_OBREAK, SIGTRAP },
+ { EXCEP_UNIMPINS, SIGILL },
+ { EXCEP_UNIMPEXINS, SIGILL },
+ { EXCEP_MEMERR, SIGSEGV },
+ { EXCEP_MISALIGN, SIGSEGV },
+ { EXCEP_BUSERROR, SIGBUS },
+ { EXCEP_ILLINSACC, SIGSEGV },
+ { EXCEP_ILLDATACC, SIGSEGV },
+ { EXCEP_IOINSACC, SIGSEGV },
+ { EXCEP_PRIVINSACC, SIGSEGV },
+ { EXCEP_PRIVDATACC, SIGSEGV },
+ { EXCEP_FPU_DISABLED, SIGFPE },
+ { EXCEP_FPU_UNIMPINS, SIGFPE },
+ { EXCEP_FPU_OPERATION, SIGFPE },
+ { EXCEP_WDT, SIGALRM },
+ { EXCEP_NMI, SIGQUIT },
+ { EXCEP_IRQ_LEVEL0, SIGINT },
+ { EXCEP_IRQ_LEVEL1, SIGINT },
+ { EXCEP_IRQ_LEVEL2, SIGINT },
+ { EXCEP_IRQ_LEVEL3, SIGINT },
+ { EXCEP_IRQ_LEVEL4, SIGINT },
+ { EXCEP_IRQ_LEVEL5, SIGINT },
+ { EXCEP_IRQ_LEVEL6, SIGINT },
+ { 0, 0}
+};
+
+/*
+ * convert the MN10300 exception code into a UNIX signal number
+ */
+static int computeSignal(enum exception_code excep)
+{
+ const struct excep_to_sig_map *map;
+
+ for (map = excep_to_sig_map; map->signo; map++)
+ if (map->excep == excep)
+ return map->signo;
+
+ return SIGHUP; /* default for things we don't know about */
+}
+
+static u32 gdbstub_fpcr, gdbstub_fpufs_array[32];
+
+/*
+ *
+ */
+static void gdbstub_store_fpu(void)
+{
+#ifdef CONFIG_FPU
+
+ asm volatile(
+ "or %2,epsw\n"
+#ifdef CONFIG_MN10300_PROC_MN103E010
+ "nop\n"
+ "nop\n"
+#endif
+ "mov %1, a1\n"
+ "fmov fs0, (a1+)\n"
+ "fmov fs1, (a1+)\n"
+ "fmov fs2, (a1+)\n"
+ "fmov fs3, (a1+)\n"
+ "fmov fs4, (a1+)\n"
+ "fmov fs5, (a1+)\n"
+ "fmov fs6, (a1+)\n"
+ "fmov fs7, (a1+)\n"
+ "fmov fs8, (a1+)\n"
+ "fmov fs9, (a1+)\n"
+ "fmov fs10, (a1+)\n"
+ "fmov fs11, (a1+)\n"
+ "fmov fs12, (a1+)\n"
+ "fmov fs13, (a1+)\n"
+ "fmov fs14, (a1+)\n"
+ "fmov fs15, (a1+)\n"
+ "fmov fs16, (a1+)\n"
+ "fmov fs17, (a1+)\n"
+ "fmov fs18, (a1+)\n"
+ "fmov fs19, (a1+)\n"
+ "fmov fs20, (a1+)\n"
+ "fmov fs21, (a1+)\n"
+ "fmov fs22, (a1+)\n"
+ "fmov fs23, (a1+)\n"
+ "fmov fs24, (a1+)\n"
+ "fmov fs25, (a1+)\n"
+ "fmov fs26, (a1+)\n"
+ "fmov fs27, (a1+)\n"
+ "fmov fs28, (a1+)\n"
+ "fmov fs29, (a1+)\n"
+ "fmov fs30, (a1+)\n"
+ "fmov fs31, (a1+)\n"
+ "fmov fpcr, %0\n"
+ : "=d"(gdbstub_fpcr)
+ : "g" (&gdbstub_fpufs_array), "i"(EPSW_FE)
+ : "a1"
+ );
+#endif
+}
+
+/*
+ *
+ */
+static void gdbstub_load_fpu(void)
+{
+#ifdef CONFIG_FPU
+
+ asm volatile(
+ "or %1,epsw\n"
+#ifdef CONFIG_MN10300_PROC_MN103E010
+ "nop\n"
+ "nop\n"
+#endif
+ "mov %0, a1\n"
+ "fmov (a1+), fs0\n"
+ "fmov (a1+), fs1\n"
+ "fmov (a1+), fs2\n"
+ "fmov (a1+), fs3\n"
+ "fmov (a1+), fs4\n"
+ "fmov (a1+), fs5\n"
+ "fmov (a1+), fs6\n"
+ "fmov (a1+), fs7\n"
+ "fmov (a1+), fs8\n"
+ "fmov (a1+), fs9\n"
+ "fmov (a1+), fs10\n"
+ "fmov (a1+), fs11\n"
+ "fmov (a1+), fs12\n"
+ "fmov (a1+), fs13\n"
+ "fmov (a1+), fs14\n"
+ "fmov (a1+), fs15\n"
+ "fmov (a1+), fs16\n"
+ "fmov (a1+), fs17\n"
+ "fmov (a1+), fs18\n"
+ "fmov (a1+), fs19\n"
+ "fmov (a1+), fs20\n"
+ "fmov (a1+), fs21\n"
+ "fmov (a1+), fs22\n"
+ "fmov (a1+), fs23\n"
+ "fmov (a1+), fs24\n"
+ "fmov (a1+), fs25\n"
+ "fmov (a1+), fs26\n"
+ "fmov (a1+), fs27\n"
+ "fmov (a1+), fs28\n"
+ "fmov (a1+), fs29\n"
+ "fmov (a1+), fs30\n"
+ "fmov (a1+), fs31\n"
+ "fmov %2, fpcr\n"
+ :
+ : "g" (&gdbstub_fpufs_array), "i"(EPSW_FE), "d"(gdbstub_fpcr)
+ : "a1"
+ );
+#endif
+}
+
+/*
+ * set a software breakpoint
+ */
+int gdbstub_set_breakpoint(u8 *addr, int len)
+{
+ int bkpt, loop, xloop;
+
+#ifdef GDBSTUB_USE_F7F7_AS_BREAKPOINT
+ len = (len + 1) & ~1;
+#endif
+
+ gdbstub_bkpt("setbkpt(%p,%d)\n", addr, len);
+
+ for (bkpt = 255; bkpt >= 0; bkpt--)
+ if (!gdbstub_bkpts[bkpt].addr)
+ break;
+ if (bkpt < 0)
+ return -ENOSPC;
+
+ for (loop = 0; loop < len; loop++)
+ if (gdbstub_read_byte(&addr[loop],
+ &gdbstub_bkpts[bkpt].origbytes[loop]
+ ) < 0)
+ return -EFAULT;
+
+ gdbstub_flush_caches = 1;
+
+#ifdef GDBSTUB_USE_F7F7_AS_BREAKPOINT
+ for (loop = 0; loop < len; loop++)
+ if (gdbstub_write_byte(0xF7, &addr[loop]) < 0)
+ goto restore;
+#else
+ for (loop = 0; loop < len; loop++)
+ if (gdbstub_write_byte(0xFF, &addr[loop]) < 0)
+ goto restore;
+#endif
+
+ gdbstub_bkpts[bkpt].addr = addr;
+ gdbstub_bkpts[bkpt].len = len;
+
+ gdbstub_bkpt("Set BKPT[%02x]: %p-%p {%02x%02x%02x%02x%02x%02x%02x}\n",
+ bkpt,
+ gdbstub_bkpts[bkpt].addr,
+ gdbstub_bkpts[bkpt].addr + gdbstub_bkpts[bkpt].len - 1,
+ gdbstub_bkpts[bkpt].origbytes[0],
+ gdbstub_bkpts[bkpt].origbytes[1],
+ gdbstub_bkpts[bkpt].origbytes[2],
+ gdbstub_bkpts[bkpt].origbytes[3],
+ gdbstub_bkpts[bkpt].origbytes[4],
+ gdbstub_bkpts[bkpt].origbytes[5],
+ gdbstub_bkpts[bkpt].origbytes[6]
+ );
+
+ return 0;
+
+restore:
+ for (xloop = 0; xloop < loop; xloop++)
+ gdbstub_write_byte(gdbstub_bkpts[bkpt].origbytes[xloop],
+ addr + xloop);
+ return -EFAULT;
+}
+
+/*
+ * clear a software breakpoint
+ */
+int gdbstub_clear_breakpoint(u8 *addr, int len)
+{
+ int bkpt, loop;
+
+#ifdef GDBSTUB_USE_F7F7_AS_BREAKPOINT
+ len = (len + 1) & ~1;
+#endif
+
+ gdbstub_bkpt("clearbkpt(%p,%d)\n", addr, len);
+
+ for (bkpt = 255; bkpt >= 0; bkpt--)
+ if (gdbstub_bkpts[bkpt].addr == addr &&
+ gdbstub_bkpts[bkpt].len == len)
+ break;
+ if (bkpt < 0)
+ return -ENOENT;
+
+ gdbstub_bkpts[bkpt].addr = NULL;
+
+ gdbstub_flush_caches = 1;
+
+ for (loop = 0; loop < len; loop++)
+ if (gdbstub_write_byte(gdbstub_bkpts[bkpt].origbytes[loop],
+ addr + loop) < 0)
+ return -EFAULT;
+
+ return 0;
+}
+
+/*
+ * This function does all command processing for interfacing to gdb
+ * - returns 1 if the exception should be skipped, 0 otherwise.
+ */
+static int gdbstub(struct pt_regs *regs, enum exception_code excep)
+{
+ unsigned long *stack;
+ unsigned long epsw, mdr;
+ uint32_t zero, ssp;
+ uint8_t broke;
+ char *ptr;
+ int sigval;
+ int addr;
+ int length;
+ int loop;
+
+ if (excep == EXCEP_FPU_DISABLED)
+ return 0;
+
+ gdbstub_flush_caches = 0;
+
+ mn10300_set_gdbleds(1);
+
+ asm volatile("mov mdr,%0" : "=d"(mdr));
+ asm volatile("mov epsw,%0" : "=d"(epsw));
+ asm volatile("mov %0,epsw"
+ :: "d"((epsw & ~EPSW_IM) | EPSW_IE | EPSW_IM_1));
+
+ gdbstub_store_fpu();
+
+#ifdef CONFIG_GDBSTUB_IMMEDIATE
+ /* skip the initial pause loop */
+ if (regs->pc == (unsigned long) __gdbstub_pause)
+ regs->pc = (unsigned long) start_kernel;
+#endif
+
+ /* if we were single stepping, restore the opcodes hoisted for the
+ * breakpoint[s] */
+ broke = 0;
+ if ((step_bp[0].addr && step_bp[0].addr == (u8 *) regs->pc) ||
+ (step_bp[1].addr && step_bp[1].addr == (u8 *) regs->pc))
+ broke = 1;
+
+ __gdbstub_restore_bp();
+
+ if (gdbstub_rx_unget) {
+ sigval = SIGINT;
+ if (gdbstub_rx_unget != 3)
+ goto packet_waiting;
+ gdbstub_rx_unget = 0;
+ }
+
+ stack = (unsigned long *) regs->sp;
+ sigval = broke ? SIGTRAP : computeSignal(excep);
+
+ /* send information about a BUG() */
+ if (!user_mode(regs) && excep == EXCEP_SYSCALL1