Commit 7ca8b9c0 authored by David Howells's avatar David Howells Committed by Linus Torvalds
Browse files

frv: extend gdbstub to support more features of gdb 



Extend gdbstub to support more features of gdb remote protocol to keep
gdb-7 and emacs gud mode happy:

 (*) The D command.  Detach debugger.

 (*) The H command.  Handle setting the target thread by ignoring it.

 (*) The qAttached command.  Indicate we 'attached' to an existing process.

 (*) The qC command.  Indicate that the current thread ID is 0.

 (*) The qOffsets command.  Indicate that no relocation has been done.

 (*) The qSymbol:: command.  Indicate that we're not interested in looking up
     any symbol addresses.

 (*) The qSupported command.  Indicate the maximum packet size and the fact
     that reverse step and continue aren't supported.

 (*) The vCont? command.  Indicate that we don't support any of its variants.

Also make it possible to trace the commands and replies without tracing
the individual character I/O.

[akpm@linux-foundation.org: make gdbstub_handle_query() static]
Signed-off-by: default avatarDavid Howells <dhowells@redhat.com>
Cc: Jason Wessel <jason.wessel@windriver.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent c6f6b596

arch/frv/include/asm/gdb-stub.h

+7 −0
Original line number Diff line number Diff line
@@ -12,6 +12,7 @@ 
#ifndef __ASM_GDB_STUB_H

#define __ASM_GDB_STUB_H



#undef GDBSTUB_DEBUG_IO

#undef GDBSTUB_DEBUG_PROTOCOL



#include <asm/ptrace.h>
@@ -108,6 +109,12 @@ extern void gdbstub_printk(const char *fmt, ...); 
extern void debug_to_serial(const char *p, int n);

extern void console_set_baud(unsigned baud);



#ifdef GDBSTUB_DEBUG_IO

#define gdbstub_io(FMT,...) gdbstub_printk(FMT, ##__VA_ARGS__)

#else

#define gdbstub_io(FMT,...) ({ 0; })

#endif



#ifdef GDBSTUB_DEBUG_PROTOCOL

#define gdbstub_proto(FMT,...) gdbstub_printk(FMT,##__VA_ARGS__)

#else

arch/frv/kernel/gdb-io.c

+2 −2
Original line number Diff line number Diff line
@@ -171,11 +171,11 @@ int gdbstub_rx_char(unsigned char *_ch, int nonblock) 
		return -EINTR;

	}

	else if (st & (UART_LSR_FE|UART_LSR_OE|UART_LSR_PE)) {

		gdbstub_proto("### GDB Rx Error (st=%02x) ###\n",st);

		gdbstub_io("### GDB Rx Error (st=%02x) ###\n",st);

		return -EIO;

	}

	else {

		gdbstub_proto("### GDB Rx %02x (st=%02x) ###\n",ch,st);

		gdbstub_io("### GDB Rx %02x (st=%02x) ###\n",ch,st);

		*_ch = ch & 0x7f;

		return 0;

	}

arch/frv/kernel/gdb-stub.c

+61 −0
Original line number Diff line number Diff line
@@ -1344,6 +1344,44 @@ void gdbstub_get_mmu_state(void) 


} /* end gdbstub_get_mmu_state() */



/*

 * handle general query commands of the form 'qXXXXX'

 */

static void gdbstub_handle_query(void)

{

	if (strcmp(input_buffer, "qAttached") == 0) {

		/* return current thread ID */

		sprintf(output_buffer, "1");

		return;

	}



	if (strcmp(input_buffer, "qC") == 0) {

		/* return current thread ID */

		sprintf(output_buffer, "QC 0");

		return;

	}



	if (strcmp(input_buffer, "qOffsets") == 0) {

		/* return relocation offset of text and data segments */

		sprintf(output_buffer, "Text=0;Data=0;Bss=0");

		return;

	}



	if (strcmp(input_buffer, "qSymbol::") == 0) {

		sprintf(output_buffer, "OK");

		return;

	}



	if (strcmp(input_buffer, "qSupported") == 0) {

		/* query of supported features */

		sprintf(output_buffer, "PacketSize=%u;ReverseContinue-;ReverseStep-",

			sizeof(input_buffer));

		return;

	}



	gdbstub_strcpy(output_buffer,"E01");

}



/*****************************************************************************/

/*

 * handle event interception and GDB remote protocol processing
@@ -1840,6 +1878,10 @@ void gdbstub(int sigval) 
		case 'k' :

			goto done;	/* just continue */



			/* detach */

		case 'D':

			gdbstub_strcpy(output_buffer, "OK");

			break;



			/* reset the whole machine (FIXME: system dependent) */

		case 'r':
@@ -1852,6 +1894,14 @@ void gdbstub(int sigval) 
			__debug_status.dcr |= DCR_SE;

			goto done;



			/* extended command */

		case 'v':

			if (strcmp(input_buffer, "vCont?") == 0) {

				output_buffer[0] = 0;

				break;

			}

			goto unsupported_cmd;



			/* set baud rate (bBB) */

		case 'b':

			ptr = &input_buffer[1];
@@ -1923,8 +1973,19 @@ void gdbstub(int sigval) 
			gdbstub_strcpy(output_buffer,"OK");

			break;



			/* Thread-setting packet */

		case 'H':

			gdbstub_strcpy(output_buffer, "OK");

			break;



		case 'q':

			gdbstub_handle_query();

			break;



		default:

		unsupported_cmd:

			gdbstub_proto("### GDB Unsupported Cmd '%s'\n",input_buffer);

			gdbstub_strcpy(output_buffer,"E01");

			break;

		}

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