diff options
Diffstat (limited to 'arch/sh/kernel/kgdb_stub.c')
-rw-r--r-- | arch/sh/kernel/kgdb_stub.c | 106 |
1 files changed, 54 insertions, 52 deletions
diff --git a/arch/sh/kernel/kgdb_stub.c b/arch/sh/kernel/kgdb_stub.c index d8927d85492e..737eadc8ce0f 100644 --- a/arch/sh/kernel/kgdb_stub.c +++ b/arch/sh/kernel/kgdb_stub.c @@ -6,11 +6,11 @@ * David Grothe <dave@gcom.com>, Tigran Aivazian <tigran@sco.com>, * Amit S. Kale <akale@veritas.com>, William Gatliff <bgat@open-widgets.com>, * Ben Lee, Steve Chamberlain and Benoit Miller <fulg@iname.com>. - * + * * This version by Henry Bell <henry.bell@st.com> * Minor modifications by Jeremy Siegel <jsiegel@mvista.com> - * - * Contains low-level support for remote debug using GDB. + * + * Contains low-level support for remote debug using GDB. * * To enable debugger support, two things need to happen. A call to * set_debug_traps() is necessary in order to allow any breakpoints @@ -48,7 +48,7 @@ * k kill (Detach GDB) * * d Toggle debug flag - * D Detach GDB + * D Detach GDB * * Hct Set thread t for operations, OK or ENN * c = 'c' (step, cont), c = 'g' (other @@ -58,7 +58,7 @@ * qfThreadInfo Get list of current threads (first) m<id> * qsThreadInfo " " " " " (subsequent) * qOffsets Get section offsets Text=x;Data=y;Bss=z - * + * * TXX Find if thread XX is alive OK or ENN * ? What was the last sigval ? SNN (signal NN) * O Output to GDB console @@ -74,7 +74,7 @@ * '$' or '#'. If <data> starts with two characters followed by * ':', then the existing stubs interpret this as a sequence number. * - * CSUM1 and CSUM2 are ascii hex representation of an 8-bit + * CSUM1 and CSUM2 are ascii hex representation of an 8-bit * checksum of <data>, the most significant nibble is sent first. * the hex digits 0-9,a-f are used. * @@ -86,8 +86,8 @@ * Responses can be run-length encoded to save space. A '*' means that * the next character is an ASCII encoding giving a repeat count which * stands for that many repititions of the character preceding the '*'. - * The encoding is n+29, yielding a printable character where n >=3 - * (which is where RLE starts to win). Don't use an n > 126. + * The encoding is n+29, yielding a printable character where n >=3 + * (which is where RLE starts to win). Don't use an n > 126. * * So "0* " means the same as "0000". */ @@ -100,12 +100,10 @@ #include <linux/delay.h> #include <linux/linkage.h> #include <linux/init.h> - -#ifdef CONFIG_SH_KGDB_CONSOLE #include <linux/console.h> -#endif - +#include <linux/sysrq.h> #include <asm/system.h> +#include <asm/cacheflush.h> #include <asm/current.h> #include <asm/signal.h> #include <asm/pgtable.h> @@ -153,7 +151,6 @@ char kgdb_in_gdb_mode; char in_nmi; /* Set during NMI to prevent reentry */ int kgdb_nofault; /* Boolean to ignore bus errs (i.e. in GDB) */ int kgdb_enabled = 1; /* Default to enabled, cmdline can disable */ -int kgdb_halt; /* Exposed for user access */ struct task_struct *kgdb_current; @@ -328,7 +325,7 @@ static int hex_to_int(char **ptr, int *int_value) } /* Copy the binary array pointed to by buf into mem. Fix $, #, - and 0x7d escaped with 0x7d. Return a pointer to the character + and 0x7d escaped with 0x7d. Return a pointer to the character after the last byte written. */ static char *ebin_to_mem(const char *buf, char *mem, int count) { @@ -452,7 +449,7 @@ static void get_packet(char *buffer, int buflen) /* Ack successful transfer */ put_debug_char('+'); - /* If a sequence char is present, reply + /* If a sequence char is present, reply the sequence ID */ if (buffer[2] == ':') { put_debug_char(buffer[0]); @@ -759,7 +756,7 @@ static short *get_step_address(void) return (short *) addr; } -/* Set up a single-step. Replace the instruction immediately after the +/* Set up a single-step. Replace the instruction immediately after the current instruction (i.e. next in the expected flow of control) with a trap instruction, so that returning will cause only a single instruction to be executed. Note that this model is slightly broken for instructions @@ -1002,10 +999,8 @@ void set_thread_msg(void) char *ptr; switch (in_buffer[1]) { - - /* To select which thread for gG etc messages, i.e. supported */ + /* To select which thread for gG etc messages, i.e. supported */ case 'g': - ptr = &in_buffer[2]; hex_to_int(&ptr, &threadid); thread = get_thread(threadid); @@ -1173,6 +1168,7 @@ static void query_msg(void) } #endif /* CONFIG_KGDB_THREAD */ +#ifdef CONFIG_SH_KGDB_CONSOLE /* * Bring up the ports.. */ @@ -1185,6 +1181,9 @@ static int kgdb_serial_setup(void) return 0; } +#else +#define kgdb_serial_setup() 0 +#endif /* The command loop, read and act on requests */ static void kgdb_command_loop(const int excep_code, const int trapa_value) @@ -1193,7 +1192,7 @@ static void kgdb_command_loop(const int excep_code, const int trapa_value) if (excep_code == NMI_VEC) { #ifndef CONFIG_KGDB_NMI - KGDB_PRINTK("Ignoring unexpected NMI?\n"); + printk(KERN_NOTICE "KGDB: Ignoring unexpected NMI?\n"); return; #else /* CONFIG_KGDB_NMI */ if (!kgdb_enabled) { @@ -1216,10 +1215,7 @@ static void kgdb_command_loop(const int excep_code, const int trapa_value) /* Enter GDB mode (e.g. after detach) */ if (!kgdb_in_gdb_mode) { /* Do serial setup, notify user, issue preemptive ack */ - kgdb_serial_setup(); - KGDB_PRINTK("Waiting for GDB (on %s%d at %d baud)\n", - (kgdb_porttype ? kgdb_porttype->name : ""), - kgdb_portnum, kgdb_baud); + printk(KERN_NOTICE "KGDB: Waiting for GDB\n"); kgdb_in_gdb_mode = 1; put_debug_char('+'); } @@ -1233,21 +1229,18 @@ static void kgdb_command_loop(const int excep_code, const int trapa_value) will later be replaced by its original one. Do NOT do this for trap 0xff, since that indicates a compiled-in breakpoint which will not be replaced (and we would retake the trap forever) */ - if ((excep_code == TRAP_VEC) && (trapa_value != (0xff << 2))) { + if ((excep_code == TRAP_VEC) && (trapa_value != (0x3c << 2))) trap_registers.pc -= 2; - } /* Undo any stepping we may have done */ undo_single_step(); while (1) { - out_buffer[0] = 0; get_packet(in_buffer, BUFMAX); /* Examine first char of buffer to see what we need to do */ switch (in_buffer[0]) { - case '?': /* Send which signal we've received */ send_signal_msg(sigval); break; @@ -1323,11 +1316,8 @@ static void kgdb_command_loop(const int excep_code, const int trapa_value) } /* There has been an exception, most likely a breakpoint. */ -asmlinkage void kgdb_handle_exception(unsigned long r4, unsigned long r5, - unsigned long r6, unsigned long r7, - struct pt_regs __regs) +static void handle_exception(struct pt_regs *regs) { - struct pt_regs *regs = RELOC_HIDE(&__regs, 0); int excep_code, vbr_val; int count; int trapa_value = ctrl_inl(TRA); @@ -1355,7 +1345,7 @@ asmlinkage void kgdb_handle_exception(unsigned long r4, unsigned long r5, kgdb_trapa_val = trapa_value; /* Act on the exception */ - kgdb_command_loop(excep_code >> 5, trapa_value); + kgdb_command_loop(excep_code, trapa_value); kgdb_current = NULL; @@ -1373,14 +1363,12 @@ asmlinkage void kgdb_handle_exception(unsigned long r4, unsigned long r5, asm("ldc %0, vbr": :"r"(vbr_val)); } -/* Trigger a breakpoint by function */ -void breakpoint(void) +asmlinkage void kgdb_handle_exception(unsigned long r4, unsigned long r5, + unsigned long r6, unsigned long r7, + struct pt_regs __regs) { - if (!kgdb_enabled) { - kgdb_enabled = 1; - kgdb_init(); - } - BREAKPOINT(); + struct pt_regs *regs = RELOC_HIDE(&__regs, 0); + handle_exception(regs); } /* Initialise the KGDB data structures and serial configuration */ @@ -1395,24 +1383,16 @@ int kgdb_init(void) kgdb_in_gdb_mode = 0; if (kgdb_serial_setup() != 0) { - KGDB_PRINTK("serial setup error\n"); + printk(KERN_NOTICE "KGDB: serial setup error\n"); return -1; } /* Init ptr to exception handler */ - kgdb_debug_hook = kgdb_handle_exception; + kgdb_debug_hook = handle_exception; kgdb_bus_err_hook = kgdb_handle_bus_error; /* Enter kgdb now if requested, or just report init done */ - if (kgdb_halt) { - kgdb_in_gdb_mode = 1; - put_debug_char('+'); - breakpoint(); - } - else - { - KGDB_PRINTK("stub is initialized.\n"); - } + printk(KERN_NOTICE "KGDB: stub is initialized.\n"); return 0; } @@ -1437,7 +1417,7 @@ static void kgdb_msg_write(const char *s, unsigned count) /* Calculate how many this time */ wcount = (count > MAXOUT) ? MAXOUT : count; - + /* Pack in hex chars */ for (i = 0; i < wcount; i++) bufptr = pack_hex_byte(bufptr, s[i]); @@ -1467,3 +1447,25 @@ void kgdb_console_write(struct console *co, const char *s, unsigned count) kgdb_msg_write(s, count); } #endif + +#ifdef CONFIG_KGDB_SYSRQ +static void sysrq_handle_gdb(int key, struct tty_struct *tty) +{ + printk("Entering GDB stub\n"); + breakpoint(); +} + +static struct sysrq_key_op sysrq_gdb_op = { + .handler = sysrq_handle_gdb, + .help_msg = "Gdb", + .action_msg = "GDB", +}; + +static int gdb_register_sysrq(void) +{ + printk("Registering GDB sysrq handler\n"); + register_sysrq_key('g', &sysrq_gdb_op); + return 0; +} +module_init(gdb_register_sysrq); +#endif |