From e460d64405c04581e42aa9cbae76815a2d4e9abe Mon Sep 17 00:00:00 2001 From: David Howells Date: Fri, 18 Mar 2011 16:54:31 +0000 Subject: [PATCH] MN10300: Use KGDB --- arch/mn10300/Kconfig | 2 + arch/mn10300/Kconfig.debug | 2 +- arch/mn10300/include/asm/kgdb.h | 81 +++++++++++++ arch/mn10300/include/asm/smp.h | 3 +- arch/mn10300/kernel/Makefile | 1 + arch/mn10300/kernel/kgdb.c | 202 ++++++++++++++++++++++++++++++++ 6 files changed, 289 insertions(+), 2 deletions(-) create mode 100644 arch/mn10300/include/asm/kgdb.h create mode 100644 arch/mn10300/kernel/kgdb.c diff --git a/arch/mn10300/Kconfig b/arch/mn10300/Kconfig index 6e9cac970024..d8ab97a73db2 100644 --- a/arch/mn10300/Kconfig +++ b/arch/mn10300/Kconfig @@ -3,6 +3,8 @@ config MN10300 select HAVE_OPROFILE select HAVE_GENERIC_HARDIRQS select GENERIC_HARDIRQS_NO_DEPRECATED + select HAVE_ARCH_TRACEHOOK + select HAVE_ARCH_KGDB config AM33_2 def_bool n diff --git a/arch/mn10300/Kconfig.debug b/arch/mn10300/Kconfig.debug index 87adb8f434ee..c2fa3a8f9eef 100644 --- a/arch/mn10300/Kconfig.debug +++ b/arch/mn10300/Kconfig.debug @@ -153,4 +153,4 @@ endmenu config KERNEL_DEBUGGER def_bool y - depends on GDBSTUB + depends on GDBSTUB || KGDB diff --git a/arch/mn10300/include/asm/kgdb.h b/arch/mn10300/include/asm/kgdb.h new file mode 100644 index 000000000000..eb245f18a708 --- /dev/null +++ b/arch/mn10300/include/asm/kgdb.h @@ -0,0 +1,81 @@ +/* Kernel debugger for MN10300 + * + * Copyright (C) 2010 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 Licence + * as published by the Free Software Foundation; either version + * 2 of the Licence, or (at your option) any later version. + */ + +#ifndef _ASM_KGDB_H +#define _ASM_KGDB_H + +/* + * 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 1024 + +/* + * Note that this register image is in a different order than the register + * image that Linux produces at interrupt time. + */ +enum regnames { + GDB_FR_D0 = 0, + GDB_FR_D1 = 1, + GDB_FR_D2 = 2, + GDB_FR_D3 = 3, + GDB_FR_A0 = 4, + GDB_FR_A1 = 5, + GDB_FR_A2 = 6, + GDB_FR_A3 = 7, + + GDB_FR_SP = 8, + GDB_FR_PC = 9, + GDB_FR_MDR = 10, + GDB_FR_EPSW = 11, + GDB_FR_LIR = 12, + GDB_FR_LAR = 13, + GDB_FR_MDRQ = 14, + + GDB_FR_E0 = 15, + GDB_FR_E1 = 16, + GDB_FR_E2 = 17, + GDB_FR_E3 = 18, + GDB_FR_E4 = 19, + GDB_FR_E5 = 20, + GDB_FR_E6 = 21, + GDB_FR_E7 = 22, + + GDB_FR_SSP = 23, + GDB_FR_MSP = 24, + GDB_FR_USP = 25, + GDB_FR_MCRH = 26, + GDB_FR_MCRL = 27, + GDB_FR_MCVF = 28, + + GDB_FR_FPCR = 29, + GDB_FR_DUMMY0 = 30, + GDB_FR_DUMMY1 = 31, + + GDB_FR_FS0 = 32, + + GDB_FR_SIZE = 64, +}; + +#define GDB_ORIG_D0 41 +#define NUMREGBYTES (GDB_FR_SIZE*4) + +static inline void arch_kgdb_breakpoint(void) +{ + asm(".globl __arch_kgdb_breakpoint; __arch_kgdb_breakpoint: break"); +} +extern u8 __arch_kgdb_breakpoint; + +#define BREAK_INSTR_SIZE 1 +#define CACHE_FLUSH_IS_SAFE 1 + +#endif /* _ASM_KGDB_H */ diff --git a/arch/mn10300/include/asm/smp.h b/arch/mn10300/include/asm/smp.h index e3d13a899855..6745dbe64944 100644 --- a/arch/mn10300/include/asm/smp.h +++ b/arch/mn10300/include/asm/smp.h @@ -62,8 +62,9 @@ * An alternate way of dealing with this could be to use the EPSW.S bits to * cache this information for systems with up to four CPUs. */ +#define arch_smp_processor_id() (CPUID) #if 0 -#define raw_smp_processor_id() (CPUID) +#define raw_smp_processor_id() (arch_smp_processor_id()) #else #define raw_smp_processor_id() (current_thread_info()->cpu) #endif diff --git a/arch/mn10300/kernel/Makefile b/arch/mn10300/kernel/Makefile index 48ab4017434d..47ed30fe8178 100644 --- a/arch/mn10300/kernel/Makefile +++ b/arch/mn10300/kernel/Makefile @@ -25,3 +25,4 @@ obj-$(CONFIG_MN10300_RTC) += rtc.o obj-$(CONFIG_PROFILE) += profile.o profile-low.o obj-$(CONFIG_MODULES) += module.o obj-$(CONFIG_KPROBES) += kprobes.o +obj-$(CONFIG_KGDB) += kgdb.o diff --git a/arch/mn10300/kernel/kgdb.c b/arch/mn10300/kernel/kgdb.c new file mode 100644 index 000000000000..7d575f553099 --- /dev/null +++ b/arch/mn10300/kernel/kgdb.c @@ -0,0 +1,202 @@ +/* kgdb support for MN10300 + * + * Copyright (C) 2010 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 Licence + * as published by the Free Software Foundation; either version + * 2 of the Licence, or (at your option) any later version. + */ + +#include +#include +#include +#include +#include +#include +#include +#include "internal.h" + +/* + * Copy kernel exception frame registers to the GDB register file + */ +void pt_regs_to_gdb_regs(unsigned long *gdb_regs, struct pt_regs *regs) +{ + unsigned long ssp = (unsigned long) (regs + 1); + + gdb_regs[GDB_FR_D0] = regs->d0; + gdb_regs[GDB_FR_D1] = regs->d1; + gdb_regs[GDB_FR_D2] = regs->d2; + gdb_regs[GDB_FR_D3] = regs->d3; + gdb_regs[GDB_FR_A0] = regs->a0; + gdb_regs[GDB_FR_A1] = regs->a1; + gdb_regs[GDB_FR_A2] = regs->a2; + gdb_regs[GDB_FR_A3] = regs->a3; + gdb_regs[GDB_FR_SP] = (regs->epsw & EPSW_nSL) ? regs->sp : ssp; + gdb_regs[GDB_FR_PC] = regs->pc; + gdb_regs[GDB_FR_MDR] = regs->mdr; + gdb_regs[GDB_FR_EPSW] = regs->epsw; + gdb_regs[GDB_FR_LIR] = regs->lir; + gdb_regs[GDB_FR_LAR] = regs->lar; + gdb_regs[GDB_FR_MDRQ] = regs->mdrq; + gdb_regs[GDB_FR_E0] = regs->e0; + gdb_regs[GDB_FR_E1] = regs->e1; + gdb_regs[GDB_FR_E2] = regs->e2; + gdb_regs[GDB_FR_E3] = regs->e3; + gdb_regs[GDB_FR_E4] = regs->e4; + gdb_regs[GDB_FR_E5] = regs->e5; + gdb_regs[GDB_FR_E6] = regs->e6; + gdb_regs[GDB_FR_E7] = regs->e7; + gdb_regs[GDB_FR_SSP] = ssp; + gdb_regs[GDB_FR_MSP] = 0; + gdb_regs[GDB_FR_USP] = regs->sp; + gdb_regs[GDB_FR_MCRH] = regs->mcrh; + gdb_regs[GDB_FR_MCRL] = regs->mcrl; + gdb_regs[GDB_FR_MCVF] = regs->mcvf; + gdb_regs[GDB_FR_DUMMY0] = 0; + gdb_regs[GDB_FR_DUMMY1] = 0; + gdb_regs[GDB_FR_FS0] = 0; +} + +/* + * Extracts kernel SP/PC values understandable by gdb from the values + * saved by switch_to(). + */ +void sleeping_thread_to_gdb_regs(unsigned long *gdb_regs, struct task_struct *p) +{ + gdb_regs[GDB_FR_SSP] = p->thread.sp; + gdb_regs[GDB_FR_PC] = p->thread.pc; + gdb_regs[GDB_FR_A3] = p->thread.a3; + gdb_regs[GDB_FR_USP] = p->thread.usp; + gdb_regs[GDB_FR_FPCR] = p->thread.fpu_state.fpcr; +} + +/* + * Fill kernel exception frame registers from the GDB register file + */ +void gdb_regs_to_pt_regs(unsigned long *gdb_regs, struct pt_regs *regs) +{ + regs->d0 = gdb_regs[GDB_FR_D0]; + regs->d1 = gdb_regs[GDB_FR_D1]; + regs->d2 = gdb_regs[GDB_FR_D2]; + regs->d3 = gdb_regs[GDB_FR_D3]; + regs->a0 = gdb_regs[GDB_FR_A0]; + regs->a1 = gdb_regs[GDB_FR_A1]; + regs->a2 = gdb_regs[GDB_FR_A2]; + regs->a3 = gdb_regs[GDB_FR_A3]; + regs->sp = gdb_regs[GDB_FR_SP]; + regs->pc = gdb_regs[GDB_FR_PC]; + regs->mdr = gdb_regs[GDB_FR_MDR]; + regs->epsw = gdb_regs[GDB_FR_EPSW]; + regs->lir = gdb_regs[GDB_FR_LIR]; + regs->lar = gdb_regs[GDB_FR_LAR]; + regs->mdrq = gdb_regs[GDB_FR_MDRQ]; + regs->e0 = gdb_regs[GDB_FR_E0]; + regs->e1 = gdb_regs[GDB_FR_E1]; + regs->e2 = gdb_regs[GDB_FR_E2]; + regs->e3 = gdb_regs[GDB_FR_E3]; + regs->e4 = gdb_regs[GDB_FR_E4]; + regs->e5 = gdb_regs[GDB_FR_E5]; + regs->e6 = gdb_regs[GDB_FR_E6]; + regs->e7 = gdb_regs[GDB_FR_E7]; + regs->sp = gdb_regs[GDB_FR_SSP]; + /* gdb_regs[GDB_FR_MSP]; */ + // regs->usp = gdb_regs[GDB_FR_USP]; + regs->mcrh = gdb_regs[GDB_FR_MCRH]; + regs->mcrl = gdb_regs[GDB_FR_MCRL]; + regs->mcvf = gdb_regs[GDB_FR_MCVF]; + /* gdb_regs[GDB_FR_DUMMY0]; */ + /* gdb_regs[GDB_FR_DUMMY1]; */ + + // regs->fpcr = gdb_regs[GDB_FR_FPCR]; + // regs->fs0 = gdb_regs[GDB_FR_FS0]; +} + +struct kgdb_arch arch_kgdb_ops = { + .gdb_bpt_instr = { 0xff }, + .flags = KGDB_HW_BREAKPOINT, +}; + +/* + * Handle unknown packets and [Ccs] packets + */ +int kgdb_arch_handle_exception(int vector, int signo, int err_code, + char *remcom_in_buffer, char *remcom_out_buffer, + struct pt_regs *regs) +{ + long addr; + char *ptr; + + switch (remcom_in_buffer[0]) { + case 'c': + if (kgdb_contthread && kgdb_contthread != current) { + strcpy(remcom_out_buffer, "E00"); + break; + } + + kgdb_contthread = NULL; + + /* try to read optional parameter, pc unchanged if no parm */ + ptr = &remcom_in_buffer[1]; + if (kgdb_hex2long(&ptr, &addr)) + regs->pc = addr; + return 0; + + case 's': + break; /* we don't do hardware single stepping */ + } + return -1; /* this means that we do not want to exit from the handler */ +} + +/* + * Handle event interception + * - returns 0 if the exception should be skipped, -ERROR otherwise. + */ +int debugger_intercept(enum exception_code excep, int signo, int si_code, + struct pt_regs *regs) +{ + int ret; + + ret = kgdb_handle_exception(excep, signo, si_code, regs); + + debugger_local_cache_flushinv(); + + return ret; +} + +/* + * Determine if we've hit a debugger special breakpoint + */ +int at_debugger_breakpoint(struct pt_regs *regs) +{ + return regs->pc == (unsigned long)&__arch_kgdb_breakpoint; +} + +/* + * Initialise kgdb + */ +int kgdb_arch_init(void) +{ + return 0; +} + +/* + * Do something, perhaps, but don't know what. + */ +void kgdb_arch_exit(void) +{ +} + +#ifdef CONFIG_SMP +void debugger_nmi_interrupt(struct pt_regs *regs, enum exception_code code) +{ + kgdb_nmicallback(arch_smp_processor_id(), regs); + debugger_local_cache_flushinv(); +} + +void kgdb_roundup_cpus(unsigned long flags) +{ + smp_jump_to_debugger(); +} +#endif