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Diffstat (limited to 'arch/hexagon/kernel/kgdb.c')
| -rw-r--r-- | arch/hexagon/kernel/kgdb.c | 258 |
1 files changed, 258 insertions, 0 deletions
diff --git a/arch/hexagon/kernel/kgdb.c b/arch/hexagon/kernel/kgdb.c new file mode 100644 index 00000000000..038580cc5ab --- /dev/null +++ b/arch/hexagon/kernel/kgdb.c @@ -0,0 +1,258 @@ +/* + * arch/hexagon/kernel/kgdb.c - Hexagon KGDB Support + * + * Copyright (c) 2011-2012, The Linux Foundation. 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 version 2 and + * only version 2 as published by the Free Software Foundation. + * + * 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, write to the Free Software + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA + * 02110-1301, USA. + */ + +#include <linux/irq.h> +#include <linux/sched.h> +#include <linux/kdebug.h> +#include <linux/kgdb.h> + +/* All registers are 4 bytes, for now */ +#define GDB_SIZEOF_REG 4 + +/* The register names are used during printing of the regs; + * Keep these at three letters to pretty-print. */ +struct dbg_reg_def_t dbg_reg_def[DBG_MAX_REG_NUM] = { + { " r0", GDB_SIZEOF_REG, offsetof(struct pt_regs, r00)}, + { " r1", GDB_SIZEOF_REG, offsetof(struct pt_regs, r01)}, + { " r2", GDB_SIZEOF_REG, offsetof(struct pt_regs, r02)}, + { " r3", GDB_SIZEOF_REG, offsetof(struct pt_regs, r03)}, + { " r4", GDB_SIZEOF_REG, offsetof(struct pt_regs, r04)}, + { " r5", GDB_SIZEOF_REG, offsetof(struct pt_regs, r05)}, + { " r6", GDB_SIZEOF_REG, offsetof(struct pt_regs, r06)}, + { " r7", GDB_SIZEOF_REG, offsetof(struct pt_regs, r07)}, + { " r8", GDB_SIZEOF_REG, offsetof(struct pt_regs, r08)}, + { " r9", GDB_SIZEOF_REG, offsetof(struct pt_regs, r09)}, + { "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, offsetof(struct pt_regs, r16)}, + { "r17", GDB_SIZEOF_REG, offsetof(struct pt_regs, r17)}, + { "r18", GDB_SIZEOF_REG, offsetof(struct pt_regs, r18)}, + { "r19", GDB_SIZEOF_REG, offsetof(struct pt_regs, r19)}, + { "r20", GDB_SIZEOF_REG, offsetof(struct pt_regs, r20)}, + { "r21", GDB_SIZEOF_REG, offsetof(struct pt_regs, r21)}, + { "r22", GDB_SIZEOF_REG, offsetof(struct pt_regs, r22)}, + { "r23", GDB_SIZEOF_REG, offsetof(struct pt_regs, r23)}, + { "r24", GDB_SIZEOF_REG, offsetof(struct pt_regs, r24)}, + { "r25", GDB_SIZEOF_REG, offsetof(struct pt_regs, r25)}, + { "r26", GDB_SIZEOF_REG, offsetof(struct pt_regs, r26)}, + { "r27", GDB_SIZEOF_REG, offsetof(struct pt_regs, r27)}, + { "r28", GDB_SIZEOF_REG, offsetof(struct pt_regs, r28)}, + { "r29", GDB_SIZEOF_REG, offsetof(struct pt_regs, r29)}, + { "r30", GDB_SIZEOF_REG, offsetof(struct pt_regs, r30)}, + { "r31", GDB_SIZEOF_REG, offsetof(struct pt_regs, r31)}, + + { "usr", GDB_SIZEOF_REG, offsetof(struct pt_regs, usr)}, + { "preds", GDB_SIZEOF_REG, offsetof(struct pt_regs, preds)}, + { " m0", GDB_SIZEOF_REG, offsetof(struct pt_regs, m0)}, + { " m1", GDB_SIZEOF_REG, offsetof(struct pt_regs, m1)}, + { "sa0", GDB_SIZEOF_REG, offsetof(struct pt_regs, sa0)}, + { "sa1", GDB_SIZEOF_REG, offsetof(struct pt_regs, sa1)}, + { "lc0", GDB_SIZEOF_REG, offsetof(struct pt_regs, lc0)}, + { "lc1", GDB_SIZEOF_REG, offsetof(struct pt_regs, lc1)}, + { " gp", GDB_SIZEOF_REG, offsetof(struct pt_regs, gp)}, + { "ugp", GDB_SIZEOF_REG, offsetof(struct pt_regs, ugp)}, + { "cs0", GDB_SIZEOF_REG, offsetof(struct pt_regs, cs0)}, + { "cs1", GDB_SIZEOF_REG, offsetof(struct pt_regs, cs1)}, + { "psp", GDB_SIZEOF_REG, offsetof(struct pt_regs, hvmer.vmpsp)}, + { "elr", GDB_SIZEOF_REG, offsetof(struct pt_regs, hvmer.vmel)}, + { "est", GDB_SIZEOF_REG, offsetof(struct pt_regs, hvmer.vmest)}, + { "badva", GDB_SIZEOF_REG, offsetof(struct pt_regs, hvmer.vmbadva)}, + { "restart_r0", GDB_SIZEOF_REG, offsetof(struct pt_regs, restart_r0)}, + { "syscall_nr", GDB_SIZEOF_REG, offsetof(struct pt_regs, syscall_nr)}, +}; + +struct kgdb_arch arch_kgdb_ops = { + /* trap0(#0xDB) 0x0cdb0054 */ + .gdb_bpt_instr = {0x54, 0x00, 0xdb, 0x0c}, +}; + +char *dbg_get_reg(int regno, void *mem, struct pt_regs *regs) +{ + if (regno >= DBG_MAX_REG_NUM || regno < 0) + return NULL; + + *((unsigned long *) mem) = *((unsigned long *) ((void *)regs + + dbg_reg_def[regno].offset)); + + 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; + + *((unsigned long *) ((void *)regs + dbg_reg_def[regno].offset)) = + *((unsigned long *) mem); + + return 0; +} + +void kgdb_arch_set_pc(struct pt_regs *regs, unsigned long pc) +{ + instruction_pointer(regs) = pc; +} + +#ifdef CONFIG_SMP + +/** + * kgdb_roundup_cpus - Get other CPUs into a holding pattern + * @flags: Current IRQ state + * + * On SMP systems, we need to get the attention of the other CPUs + * and get them be in a known state. This should do what is needed + * to get the other CPUs to call kgdb_wait(). Note that on some arches, + * the NMI approach is not used for rounding up all the CPUs. For example, + * in case of MIPS, smp_call_function() is used to roundup CPUs. In + * this case, we have to make sure that interrupts are enabled before + * calling smp_call_function(). The argument to this function is + * the flags that will be used when restoring the interrupts. There is + * local_irq_save() call before kgdb_roundup_cpus(). + * + * On non-SMP systems, this is not called. + */ + +static void hexagon_kgdb_nmi_hook(void *ignored) +{ + kgdb_nmicallback(raw_smp_processor_id(), get_irq_regs()); +} + +void kgdb_roundup_cpus(unsigned long flags) +{ + local_irq_enable(); + smp_call_function(hexagon_kgdb_nmi_hook, NULL, 0); + local_irq_disable(); +} +#endif + + +/* Not yet working */ +void sleeping_thread_to_gdb_regs(unsigned long *gdb_regs, + struct task_struct *task) +{ + struct pt_regs *thread_regs; + + if (task == NULL) + return; + + /* Initialize to zero */ + memset(gdb_regs, 0, NUMREGBYTES); + + /* Otherwise, we have only some registers from switch_to() */ + thread_regs = task_pt_regs(task); + gdb_regs[0] = thread_regs->r00; +} + +/** + * kgdb_arch_handle_exception - Handle architecture specific GDB packets. + * @vector: The error vector of the exception that happened. + * @signo: The signal number of the exception that happened. + * @err_code: The error code of the exception that happened. + * @remcom_in_buffer: The buffer of the packet we have read. + * @remcom_out_buffer: The buffer of %BUFMAX bytes to write a packet into. + * @regs: The &struct pt_regs of the current process. + * + * This function MUST handle the 'c' and 's' command packets, + * as well packets to set / remove a hardware breakpoint, if used. + * If there are additional packets which the hardware needs to handle, + * they are handled here. The code should return -1 if it wants to + * process more packets, and a %0 or %1 if it wants to exit from the + * kgdb callback. + * + * Not yet working. + */ +int kgdb_arch_handle_exception(int vector, int signo, int err_code, + char *remcom_in_buffer, char *remcom_out_buffer, + struct pt_regs *linux_regs) +{ + switch (remcom_in_buffer[0]) { + case 's': + case 'c': + return 0; + } + /* Stay in the debugger. */ + return -1; +} + +static int __kgdb_notify(struct die_args *args, unsigned long cmd) +{ + /* cpu roundup */ + if (atomic_read(&kgdb_active) != -1) { + kgdb_nmicallback(smp_processor_id(), args->regs); + return NOTIFY_STOP; + } + + if (user_mode(args->regs)) + return NOTIFY_DONE; + + if (kgdb_handle_exception(args->trapnr & 0xff, args->signr, args->err, + args->regs)) + return NOTIFY_DONE; + + return NOTIFY_STOP; +} + +static int +kgdb_notify(struct notifier_block *self, unsigned long cmd, void *ptr) +{ + unsigned long flags; + int ret; + + local_irq_save(flags); + ret = __kgdb_notify(ptr, cmd); + local_irq_restore(flags); + + return ret; +} + +static struct notifier_block kgdb_notifier = { + .notifier_call = kgdb_notify, + + /* + * Lowest-prio notifier priority, we want to be notified last: + */ + .priority = -INT_MAX, +}; + +/** + * kgdb_arch_init - Perform any architecture specific initalization. + * + * This function will handle the initalization of any architecture + * specific callbacks. + */ +int kgdb_arch_init(void) +{ + return register_die_notifier(&kgdb_notifier); +} + +/** + * kgdb_arch_exit - Perform any architecture specific uninitalization. + * + * This function will handle the uninitalization of any architecture + * specific callbacks, for dynamic registration and unregistration. + */ +void kgdb_arch_exit(void) +{ + unregister_die_notifier(&kgdb_notifier); +} |