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author | Chris Metcalf <cmetcalf@tilera.com> | 2013-08-29 03:53:17 +0400 |
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committer | Chris Metcalf <cmetcalf@tilera.com> | 2013-09-03 22:51:26 +0400 |
commit | 8157107b13099d6eb2e8ccd00b9aba009c698c38 (patch) | |
tree | 960e84859e05071a00a1e755b023dfbf3da939f0 /arch/tile/include | |
parent | b5c6c1a72afcc416c11ad932589054dcd3125782 (diff) | |
download | linux-8157107b13099d6eb2e8ccd00b9aba009c698c38.tar.xz |
tilegx: support KGDB
Enter kernel debugger at boot with:
--hvd UART_1=1 --hvx kgdbwait --hvx kgdboc=ttyS1,115200
or at runtime with:
echo ttyS1,115200 > /sys/module/kgdboc/parameters/kgdboc
echo g > /proc/sysrq-trigger
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
Diffstat (limited to 'arch/tile/include')
-rw-r--r-- | arch/tile/include/asm/kgdb.h | 71 |
1 files changed, 71 insertions, 0 deletions
diff --git a/arch/tile/include/asm/kgdb.h b/arch/tile/include/asm/kgdb.h new file mode 100644 index 000000000000..280c181cf0db --- /dev/null +++ b/arch/tile/include/asm/kgdb.h @@ -0,0 +1,71 @@ +/* + * Copyright 2013 Tilera Corporation. All Rights Reserved. + * + * 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, version 2. + * + * This program 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, GOOD TITLE or + * NON INFRINGEMENT. See the GNU General Public License for + * more details. + * + * TILE-Gx KGDB support. + */ + +#ifndef __TILE_KGDB_H__ +#define __TILE_KGDB_H__ + +#include <linux/kdebug.h> +#include <arch/opcode.h> + +#define GDB_SIZEOF_REG sizeof(unsigned long) + +/* + * TILE-Gx gdb is expecting the following register layout: + * 56 GPRs(R0 - R52, TP, SP, LR), 8 special GPRs(networks and ZERO), + * plus the PC and the faultnum. + * + * Even though kernel not use the 8 special GPRs, they need to be present + * in the registers sent for correct processing in the host-side gdb. + * + */ +#define DBG_MAX_REG_NUM (56+8+2) +#define NUMREGBYTES (DBG_MAX_REG_NUM * GDB_SIZEOF_REG) + +/* + * BUFMAX defines the maximum number of characters in inbound/outbound + * buffers at least NUMREGBYTES*2 are needed for register packets, + * Longer buffer is needed to list all threads. + */ +#define BUFMAX 2048 + +#define BREAK_INSTR_SIZE TILEGX_BUNDLE_SIZE_IN_BYTES + +/* + * Require cache flush for set/clear a software breakpoint or write memory. + */ +#define CACHE_FLUSH_IS_SAFE 1 + +/* + * The compiled-in breakpoint instruction can be used to "break" into + * the debugger via magic system request key (sysrq-G). + */ +static tile_bundle_bits compiled_bpt = TILEGX_BPT_BUNDLE | DIE_COMPILED_BPT; + +enum tilegx_regnum { + TILEGX_PC_REGNUM = TREG_LAST_GPR + 9, + TILEGX_FAULTNUM_REGNUM, +}; + +/* + * Generate a breakpoint exception to "break" into the debugger. + */ +static inline void arch_kgdb_breakpoint(void) +{ + asm volatile (".quad %0\n\t" + ::""(compiled_bpt)); +} + +#endif /* __TILE_KGDB_H__ */ |