From d16d2be111a61baf3a4696f07bfc7a8e36697cec Mon Sep 17 00:00:00 2001 From: Ley Foon Tan Date: Mon, 16 Feb 2015 19:26:43 +0800 Subject: [PATCH] nios2: add kgdb support Signed-off-by: Ley Foon Tan --- arch/nios2/Kconfig | 1 + arch/nios2/include/asm/kgdb.h | 93 ++++++++++++++++++ arch/nios2/kernel/Makefile | 1 + arch/nios2/kernel/entry.S | 12 ++- arch/nios2/kernel/kgdb.c | 171 ++++++++++++++++++++++++++++++++++ 5 files changed, 277 insertions(+), 1 deletion(-) create mode 100644 arch/nios2/include/asm/kgdb.h create mode 100644 arch/nios2/kernel/kgdb.c diff --git a/arch/nios2/Kconfig b/arch/nios2/Kconfig index f77991ecfd8e..437555424bda 100644 --- a/arch/nios2/Kconfig +++ b/arch/nios2/Kconfig @@ -8,6 +8,7 @@ config NIOS2 select GENERIC_IRQ_PROBE select GENERIC_IRQ_SHOW select HAVE_ARCH_TRACEHOOK + select HAVE_ARCH_KGDB select IRQ_DOMAIN select MODULES_USE_ELF_RELA select OF diff --git a/arch/nios2/include/asm/kgdb.h b/arch/nios2/include/asm/kgdb.h new file mode 100644 index 000000000000..8fd5e3b66c57 --- /dev/null +++ b/arch/nios2/include/asm/kgdb.h @@ -0,0 +1,93 @@ +/* + * Copyright (C) 2015 Altera Corporation + * Copyright (C) 2011 Tobias Klauser + * + * Based on the code posted by Kazuyasu on the Altera Forum at: + * http://www.alteraforum.com/forum/showpost.php?p=77003&postcount=20 + * + * 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; either version 2 of the License, or + * (at your option) any later version. + * + * 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. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program. If not, see . + * + */ + +#ifndef _ASM_NIOS2_KGDB_H +#define _ASM_NIOS2_KGDB_H + +#define CACHE_FLUSH_IS_SAFE 1 +#define BUFMAX 2048 + +enum regnames { + GDB_R0 = 0, + GDB_AT, + GDB_R2, + GDB_R3, + GDB_R4, + GDB_R5, + GDB_R6, + GDB_R7, + GDB_R8, + GDB_R9, + GDB_R10, + GDB_R11, + GDB_R12, + GDB_R13, + GDB_R14, + GDB_R15, + GDB_R16, + GDB_R17, + GDB_R18, + GDB_R19, + GDB_R20, + GDB_R21, + GDB_R22, + GDB_R23, + GDB_ET, + GDB_BT, + GDB_GP, + GDB_SP, + GDB_FP, + GDB_EA, + GDB_BA, + GDB_RA, + GDB_PC, + GDB_STATUS, + GDB_ESTATUS, + GDB_BSTATUS, + GDB_IENABLE, + GDB_IPENDING, + GDB_CPUID, + GDB_CTL6, + GDB_EXCEPTION, + GDB_PTEADDR, + GDB_TLBACC, + GDB_TLBMISC, + GDB_ECCINJ, + GDB_BADADDR, + GDB_CONFIG, + GDB_MPUBASE, + GDB_MPUACC, + /* do not change the last entry or anything below! */ + GDB_NUMREGBYTES /* number of registers */ +}; + +#define GDB_SIZEOF_REG sizeof(u32) +#define DBG_MAX_REG_NUM (49) +#define NUMREGBYTES (DBG_MAX_REG_NUM * sizeof(GDB_SIZEOF_REG)) + +#define BREAK_INSTR_SIZE 4 +static inline void arch_kgdb_breakpoint(void) +{ + __asm__ __volatile__("trap 30\n"); +} + +#endif /* _ASM_NIOS2_KGDB_H */ diff --git a/arch/nios2/kernel/Makefile b/arch/nios2/kernel/Makefile index eaaa894c432f..1aae25703657 100644 --- a/arch/nios2/kernel/Makefile +++ b/arch/nios2/kernel/Makefile @@ -21,5 +21,6 @@ obj-y += time.o obj-y += traps.o obj-$(CONFIG_EARLY_PRINTK) += early_printk.o +obj-$(CONFIG_KGDB) += kgdb.o obj-$(CONFIG_MODULES) += module.o obj-$(CONFIG_NIOS2_ALIGNMENT_TRAP) += misaligned.o diff --git a/arch/nios2/kernel/entry.S b/arch/nios2/kernel/entry.S index 0bdfd13ff98b..7729bd3f2e79 100644 --- a/arch/nios2/kernel/entry.S +++ b/arch/nios2/kernel/entry.S @@ -121,7 +121,11 @@ trap_table: .word instruction_trap /* 27 */ .word instruction_trap /* 28 */ .word instruction_trap /* 29 */ - .word instruction_trap /* 30 */ +#ifdef CONFIG_KGDB + .word handle_kgdb_breakpoint /* 30 KGDB breakpoint */ +#else + .word instruction_trap /* 30 */ +#endif .word handle_breakpoint /* 31 */ .text @@ -445,6 +449,12 @@ handle_diverror: call handle_diverror_c br ret_from_exception +#ifdef CONFIG_KGDB +handle_kgdb_breakpoint: + call kgdb_breakpoint_c + br ret_from_exception +#endif + /* * Beware - when entering resume, prev (the current task) is * in r4, next (the new task) is in r5, don't change these diff --git a/arch/nios2/kernel/kgdb.c b/arch/nios2/kernel/kgdb.c new file mode 100644 index 000000000000..117859122d1c --- /dev/null +++ b/arch/nios2/kernel/kgdb.c @@ -0,0 +1,171 @@ +/* + * Nios2 KGDB support + * + * Copyright (C) 2015 Altera Corporation + * Copyright (C) 2011 Tobias Klauser + * + * Based on the code posted by Kazuyasu on the Altera Forum at: + * http://www.alteraforum.com/forum/showpost.php?p=77003&postcount=20 + * + * 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; either version 2 of the License, or + * (at your option) any later version. + * + * 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. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program. If not, see . + * + */ +#include +#include +#include +#include + +static int wait_for_remote_debugger; + +struct dbg_reg_def_t dbg_reg_def[DBG_MAX_REG_NUM] = +{ + { "zero", GDB_SIZEOF_REG, -1 }, + { "at", GDB_SIZEOF_REG, offsetof(struct pt_regs, r1) }, + { "r2", GDB_SIZEOF_REG, offsetof(struct pt_regs, r2) }, + { "r3", GDB_SIZEOF_REG, offsetof(struct pt_regs, r3) }, + { "r4", GDB_SIZEOF_REG, offsetof(struct pt_regs, r4) }, + { "r5", GDB_SIZEOF_REG, offsetof(struct pt_regs, r5) }, + { "r6", GDB_SIZEOF_REG, offsetof(struct pt_regs, r6) }, + { "r7", GDB_SIZEOF_REG, offsetof(struct pt_regs, r7) }, + { "r8", GDB_SIZEOF_REG, offsetof(struct pt_regs, r8) }, + { "r9", GDB_SIZEOF_REG, offsetof(struct pt_regs, r9) }, + { "r10", GDB_SIZEOF_REG, offsetof(struct pt_regs, r10) }, + { "r11", GDB_SIZEOF_REG, offsetof(struct pt_regs, r11) }, + { "r12", GDB_SIZEOF_REG, offsetof(struct pt_regs, r12) }, + { "r13", GDB_SIZEOF_REG, offsetof(struct pt_regs, r13) }, + { "r14", GDB_SIZEOF_REG, offsetof(struct pt_regs, r14) }, + { "r15", GDB_SIZEOF_REG, offsetof(struct pt_regs, r15) }, + { "r16", GDB_SIZEOF_REG, -1 }, + { "r17", GDB_SIZEOF_REG, -1 }, + { "r18", GDB_SIZEOF_REG, -1 }, + { "r19", GDB_SIZEOF_REG, -1 }, + { "r20", GDB_SIZEOF_REG, -1 }, + { "r21", GDB_SIZEOF_REG, -1 }, + { "r22", GDB_SIZEOF_REG, -1 }, + { "r23", GDB_SIZEOF_REG, -1 }, + { "et", GDB_SIZEOF_REG, -1 }, + { "bt", GDB_SIZEOF_REG, -1 }, + { "gp", GDB_SIZEOF_REG, offsetof(struct pt_regs, gp) }, + { "sp", GDB_SIZEOF_REG, offsetof(struct pt_regs, sp) }, + { "fp", GDB_SIZEOF_REG, offsetof(struct pt_regs, fp) }, + { "ea", GDB_SIZEOF_REG, -1 }, + { "ba", GDB_SIZEOF_REG, -1 }, + { "ra", GDB_SIZEOF_REG, offsetof(struct pt_regs, ra) }, + { "pc", GDB_SIZEOF_REG, offsetof(struct pt_regs, ea) }, + { "status", GDB_SIZEOF_REG, -1 }, + { "estatus", GDB_SIZEOF_REG, offsetof(struct pt_regs, estatus) }, + { "bstatus", GDB_SIZEOF_REG, -1 }, + { "ienable", GDB_SIZEOF_REG, -1 }, + { "ipending", GDB_SIZEOF_REG, -1}, + { "cpuid", GDB_SIZEOF_REG, -1 }, + { "ctl6", GDB_SIZEOF_REG, -1 }, + { "exception", GDB_SIZEOF_REG, -1 }, + { "pteaddr", GDB_SIZEOF_REG, -1 }, + { "tlbacc", GDB_SIZEOF_REG, -1 }, + { "tlbmisc", GDB_SIZEOF_REG, -1 }, + { "eccinj", GDB_SIZEOF_REG, -1 }, + { "badaddr", GDB_SIZEOF_REG, -1 }, + { "config", GDB_SIZEOF_REG, -1 }, + { "mpubase", GDB_SIZEOF_REG, -1 }, + { "mpuacc", GDB_SIZEOF_REG, -1 }, +}; + +char *dbg_get_reg(int regno, void *mem, struct pt_regs *regs) +{ + if (regno >= DBG_MAX_REG_NUM || regno < 0) + return NULL; + + if (dbg_reg_def[regno].offset != -1) + memcpy(mem, (void *)regs + dbg_reg_def[regno].offset, + dbg_reg_def[regno].size); + else + memset(mem, 0, dbg_reg_def[regno].size); + + return dbg_reg_def[regno].name; +} + +int dbg_set_reg(int regno, void *mem, struct pt_regs *regs) +{ + if (regno >= DBG_MAX_REG_NUM || regno < 0) + return -EINVAL; + + if (dbg_reg_def[regno].offset != -1) + memcpy((void *)regs + dbg_reg_def[regno].offset, mem, + dbg_reg_def[regno].size); + + return 0; +} + +void sleeping_thread_to_gdb_regs(unsigned long *gdb_regs, struct task_struct *p) +{ + memset((char *)gdb_regs, 0, NUMREGBYTES); + gdb_regs[GDB_SP] = p->thread.kregs->sp; + gdb_regs[GDB_PC] = p->thread.kregs->ea; +} + +void kgdb_arch_set_pc(struct pt_regs *regs, unsigned long pc) +{ + regs->ea = pc; +} + +int kgdb_arch_handle_exception(int vector, int signo, int err_code, + char *remcom_in_buffer, char *remcom_out_buffer, + struct pt_regs *regs) +{ + char *ptr; + unsigned long addr; + + switch (remcom_in_buffer[0]) { + case 's': + case 'c': + /* handle the optional parameters */ + ptr = &remcom_in_buffer[1]; + if (kgdb_hex2long(&ptr, &addr)) + regs->ea = addr; + + return 0; + } + + return -1; /* this means that we do not want to exit from the handler */ +} + +asmlinkage void kgdb_breakpoint_c(struct pt_regs *regs) +{ + /* + * The breakpoint entry code has moved the PC on by 4 bytes, so we must + * move it back. This could be done on the host but we do it here + */ + if (!wait_for_remote_debugger) + regs->ea -= 4; + else /* pass the first trap 30 code */ + wait_for_remote_debugger = 0; + + kgdb_handle_exception(30, SIGTRAP, 0, regs); +} + +int kgdb_arch_init(void) +{ + wait_for_remote_debugger = 1; + return 0; +} + +void kgdb_arch_exit(void) +{ + /* Nothing to do */ +} + +struct kgdb_arch arch_kgdb_ops = { + /* Breakpoint instruction: trap 30 */ + .gdb_bpt_instr = { 0xba, 0x6f, 0x3b, 0x00 }, +};