728 lines
18 KiB
C
728 lines
18 KiB
C
// SPDX-License-Identifier: GPL-2.0-only
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/*
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* LoongArch KGDB support
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*
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* Copyright (C) 2023 Loongson Technology Corporation Limited
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*/
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#include <linux/hw_breakpoint.h>
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#include <linux/kdebug.h>
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#include <linux/kgdb.h>
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#include <linux/processor.h>
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#include <linux/ptrace.h>
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#include <linux/sched.h>
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#include <linux/smp.h>
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#include <asm/cacheflush.h>
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#include <asm/fpu.h>
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#include <asm/hw_breakpoint.h>
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#include <asm/inst.h>
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#include <asm/irq_regs.h>
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#include <asm/ptrace.h>
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#include <asm/sigcontext.h>
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int kgdb_watch_activated;
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static unsigned int stepped_opcode;
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static unsigned long stepped_address;
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struct dbg_reg_def_t dbg_reg_def[DBG_MAX_REG_NUM] = {
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{ "r0", GDB_SIZEOF_REG, offsetof(struct pt_regs, regs[0]) },
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{ "r1", GDB_SIZEOF_REG, offsetof(struct pt_regs, regs[1]) },
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{ "r2", GDB_SIZEOF_REG, offsetof(struct pt_regs, regs[2]) },
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{ "r3", GDB_SIZEOF_REG, offsetof(struct pt_regs, regs[3]) },
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{ "r4", GDB_SIZEOF_REG, offsetof(struct pt_regs, regs[4]) },
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{ "r5", GDB_SIZEOF_REG, offsetof(struct pt_regs, regs[5]) },
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{ "r6", GDB_SIZEOF_REG, offsetof(struct pt_regs, regs[6]) },
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{ "r7", GDB_SIZEOF_REG, offsetof(struct pt_regs, regs[7]) },
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{ "r8", GDB_SIZEOF_REG, offsetof(struct pt_regs, regs[8]) },
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{ "r9", GDB_SIZEOF_REG, offsetof(struct pt_regs, regs[9]) },
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{ "r10", GDB_SIZEOF_REG, offsetof(struct pt_regs, regs[10]) },
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{ "r11", GDB_SIZEOF_REG, offsetof(struct pt_regs, regs[11]) },
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{ "r12", GDB_SIZEOF_REG, offsetof(struct pt_regs, regs[12]) },
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{ "r13", GDB_SIZEOF_REG, offsetof(struct pt_regs, regs[13]) },
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{ "r14", GDB_SIZEOF_REG, offsetof(struct pt_regs, regs[14]) },
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{ "r15", GDB_SIZEOF_REG, offsetof(struct pt_regs, regs[15]) },
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{ "r16", GDB_SIZEOF_REG, offsetof(struct pt_regs, regs[16]) },
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{ "r17", GDB_SIZEOF_REG, offsetof(struct pt_regs, regs[17]) },
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{ "r18", GDB_SIZEOF_REG, offsetof(struct pt_regs, regs[18]) },
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{ "r19", GDB_SIZEOF_REG, offsetof(struct pt_regs, regs[19]) },
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{ "r20", GDB_SIZEOF_REG, offsetof(struct pt_regs, regs[20]) },
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{ "r21", GDB_SIZEOF_REG, offsetof(struct pt_regs, regs[21]) },
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{ "r22", GDB_SIZEOF_REG, offsetof(struct pt_regs, regs[22]) },
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{ "r23", GDB_SIZEOF_REG, offsetof(struct pt_regs, regs[23]) },
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{ "r24", GDB_SIZEOF_REG, offsetof(struct pt_regs, regs[24]) },
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{ "r25", GDB_SIZEOF_REG, offsetof(struct pt_regs, regs[25]) },
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{ "r26", GDB_SIZEOF_REG, offsetof(struct pt_regs, regs[26]) },
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{ "r27", GDB_SIZEOF_REG, offsetof(struct pt_regs, regs[27]) },
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{ "r28", GDB_SIZEOF_REG, offsetof(struct pt_regs, regs[28]) },
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{ "r29", GDB_SIZEOF_REG, offsetof(struct pt_regs, regs[29]) },
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{ "r30", GDB_SIZEOF_REG, offsetof(struct pt_regs, regs[30]) },
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{ "r31", GDB_SIZEOF_REG, offsetof(struct pt_regs, regs[31]) },
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{ "orig_a0", GDB_SIZEOF_REG, offsetof(struct pt_regs, orig_a0) },
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{ "pc", GDB_SIZEOF_REG, offsetof(struct pt_regs, csr_era) },
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{ "badv", GDB_SIZEOF_REG, offsetof(struct pt_regs, csr_badvaddr) },
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{ "f0", GDB_SIZEOF_REG, 0 },
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{ "f1", GDB_SIZEOF_REG, 1 },
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{ "f2", GDB_SIZEOF_REG, 2 },
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{ "f3", GDB_SIZEOF_REG, 3 },
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{ "f4", GDB_SIZEOF_REG, 4 },
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{ "f5", GDB_SIZEOF_REG, 5 },
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{ "f6", GDB_SIZEOF_REG, 6 },
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{ "f7", GDB_SIZEOF_REG, 7 },
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{ "f8", GDB_SIZEOF_REG, 8 },
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{ "f9", GDB_SIZEOF_REG, 9 },
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{ "f10", GDB_SIZEOF_REG, 10 },
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{ "f11", GDB_SIZEOF_REG, 11 },
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{ "f12", GDB_SIZEOF_REG, 12 },
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{ "f13", GDB_SIZEOF_REG, 13 },
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{ "f14", GDB_SIZEOF_REG, 14 },
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{ "f15", GDB_SIZEOF_REG, 15 },
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{ "f16", GDB_SIZEOF_REG, 16 },
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{ "f17", GDB_SIZEOF_REG, 17 },
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{ "f18", GDB_SIZEOF_REG, 18 },
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{ "f19", GDB_SIZEOF_REG, 19 },
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{ "f20", GDB_SIZEOF_REG, 20 },
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{ "f21", GDB_SIZEOF_REG, 21 },
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{ "f22", GDB_SIZEOF_REG, 22 },
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{ "f23", GDB_SIZEOF_REG, 23 },
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{ "f24", GDB_SIZEOF_REG, 24 },
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{ "f25", GDB_SIZEOF_REG, 25 },
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{ "f26", GDB_SIZEOF_REG, 26 },
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{ "f27", GDB_SIZEOF_REG, 27 },
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{ "f28", GDB_SIZEOF_REG, 28 },
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{ "f29", GDB_SIZEOF_REG, 29 },
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{ "f30", GDB_SIZEOF_REG, 30 },
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{ "f31", GDB_SIZEOF_REG, 31 },
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{ "fcc0", 1, 0 },
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{ "fcc1", 1, 1 },
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{ "fcc2", 1, 2 },
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{ "fcc3", 1, 3 },
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{ "fcc4", 1, 4 },
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{ "fcc5", 1, 5 },
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{ "fcc6", 1, 6 },
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{ "fcc7", 1, 7 },
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{ "fcsr", 4, 0 },
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};
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char *dbg_get_reg(int regno, void *mem, struct pt_regs *regs)
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{
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int reg_offset, reg_size;
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if (regno < 0 || regno >= DBG_MAX_REG_NUM)
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return NULL;
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reg_offset = dbg_reg_def[regno].offset;
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reg_size = dbg_reg_def[regno].size;
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if (reg_offset == -1)
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goto out;
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/* Handle general-purpose/orig_a0/pc/badv registers */
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if (regno <= DBG_PT_REGS_END) {
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memcpy(mem, (void *)regs + reg_offset, reg_size);
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goto out;
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}
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if (!(regs->csr_euen & CSR_EUEN_FPEN))
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goto out;
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save_fp(current);
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/* Handle FP registers */
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switch (regno) {
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case DBG_FCSR: /* Process the fcsr */
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memcpy(mem, (void *)¤t->thread.fpu.fcsr, reg_size);
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break;
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case DBG_FCC_BASE ... DBG_FCC_END: /* Process the fcc */
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memcpy(mem, (void *)¤t->thread.fpu.fcc + reg_offset, reg_size);
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break;
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case DBG_FPR_BASE ... DBG_FPR_END: /* Process the fpr */
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memcpy(mem, (void *)¤t->thread.fpu.fpr[reg_offset], reg_size);
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break;
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default:
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break;
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}
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out:
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return dbg_reg_def[regno].name;
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}
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int dbg_set_reg(int regno, void *mem, struct pt_regs *regs)
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{
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int reg_offset, reg_size;
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if (regno < 0 || regno >= DBG_MAX_REG_NUM)
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return -EINVAL;
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reg_offset = dbg_reg_def[regno].offset;
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reg_size = dbg_reg_def[regno].size;
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if (reg_offset == -1)
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return 0;
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/* Handle general-purpose/orig_a0/pc/badv registers */
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if (regno <= DBG_PT_REGS_END) {
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memcpy((void *)regs + reg_offset, mem, reg_size);
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return 0;
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}
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if (!(regs->csr_euen & CSR_EUEN_FPEN))
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return 0;
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/* Handle FP registers */
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switch (regno) {
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case DBG_FCSR: /* Process the fcsr */
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memcpy((void *)¤t->thread.fpu.fcsr, mem, reg_size);
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break;
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case DBG_FCC_BASE ... DBG_FCC_END: /* Process the fcc */
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memcpy((void *)¤t->thread.fpu.fcc + reg_offset, mem, reg_size);
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break;
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case DBG_FPR_BASE ... DBG_FPR_END: /* Process the fpr */
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memcpy((void *)¤t->thread.fpu.fpr[reg_offset], mem, reg_size);
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break;
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default:
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break;
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}
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restore_fp(current);
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return 0;
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}
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/*
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* Similar to regs_to_gdb_regs() except that process is sleeping and so
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* we may not be able to get all the info.
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*/
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void sleeping_thread_to_gdb_regs(unsigned long *gdb_regs, struct task_struct *p)
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{
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/* Initialize to zero */
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memset((char *)gdb_regs, 0, NUMREGBYTES);
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gdb_regs[DBG_LOONGARCH_RA] = p->thread.reg01;
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gdb_regs[DBG_LOONGARCH_TP] = (long)p;
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gdb_regs[DBG_LOONGARCH_SP] = p->thread.reg03;
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/* S0 - S8 */
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gdb_regs[DBG_LOONGARCH_S0] = p->thread.reg23;
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gdb_regs[DBG_LOONGARCH_S1] = p->thread.reg24;
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gdb_regs[DBG_LOONGARCH_S2] = p->thread.reg25;
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gdb_regs[DBG_LOONGARCH_S3] = p->thread.reg26;
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gdb_regs[DBG_LOONGARCH_S4] = p->thread.reg27;
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gdb_regs[DBG_LOONGARCH_S5] = p->thread.reg28;
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gdb_regs[DBG_LOONGARCH_S6] = p->thread.reg29;
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gdb_regs[DBG_LOONGARCH_S7] = p->thread.reg30;
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gdb_regs[DBG_LOONGARCH_S8] = p->thread.reg31;
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/*
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* PC use return address (RA), i.e. the moment after return from __switch_to()
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*/
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gdb_regs[DBG_LOONGARCH_PC] = p->thread.reg01;
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}
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void kgdb_arch_set_pc(struct pt_regs *regs, unsigned long pc)
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{
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regs->csr_era = pc;
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}
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void arch_kgdb_breakpoint(void)
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{
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__asm__ __volatile__ ( \
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".globl kgdb_breakinst\n\t" \
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"nop\n" \
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"kgdb_breakinst:\tbreak 2\n\t"); /* BRK_KDB = 2 */
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}
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/*
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* Calls linux_debug_hook before the kernel dies. If KGDB is enabled,
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* then try to fall into the debugger
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*/
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static int kgdb_loongarch_notify(struct notifier_block *self, unsigned long cmd, void *ptr)
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{
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struct die_args *args = (struct die_args *)ptr;
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struct pt_regs *regs = args->regs;
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/* Userspace events, ignore. */
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if (user_mode(regs))
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return NOTIFY_DONE;
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if (!kgdb_io_module_registered)
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return NOTIFY_DONE;
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if (atomic_read(&kgdb_active) != -1)
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kgdb_nmicallback(smp_processor_id(), regs);
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if (kgdb_handle_exception(args->trapnr, args->signr, cmd, regs))
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return NOTIFY_DONE;
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if (atomic_read(&kgdb_setting_breakpoint))
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if (regs->csr_era == (unsigned long)&kgdb_breakinst)
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regs->csr_era += LOONGARCH_INSN_SIZE;
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return NOTIFY_STOP;
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}
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bool kgdb_breakpoint_handler(struct pt_regs *regs)
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{
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struct die_args args = {
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.regs = regs,
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.str = "Break",
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.err = BRK_KDB,
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.trapnr = read_csr_excode(),
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.signr = SIGTRAP,
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};
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return (kgdb_loongarch_notify(NULL, DIE_TRAP, &args) == NOTIFY_STOP) ? true : false;
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}
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static struct notifier_block kgdb_notifier = {
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.notifier_call = kgdb_loongarch_notify,
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};
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static inline void kgdb_arch_update_addr(struct pt_regs *regs,
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char *remcom_in_buffer)
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{
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unsigned long addr;
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char *ptr;
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ptr = &remcom_in_buffer[1];
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if (kgdb_hex2long(&ptr, &addr))
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regs->csr_era = addr;
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}
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/* Calculate the new address for after a step */
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static int get_step_address(struct pt_regs *regs, unsigned long *next_addr)
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{
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char cj_val;
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unsigned int si, si_l, si_h, rd, rj, cj;
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unsigned long pc = instruction_pointer(regs);
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union loongarch_instruction *ip = (union loongarch_instruction *)pc;
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if (pc & 3) {
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pr_warn("%s: invalid pc 0x%lx\n", __func__, pc);
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return -EINVAL;
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}
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*next_addr = pc + LOONGARCH_INSN_SIZE;
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si_h = ip->reg0i26_format.immediate_h;
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si_l = ip->reg0i26_format.immediate_l;
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switch (ip->reg0i26_format.opcode) {
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case b_op:
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*next_addr = pc + sign_extend64((si_h << 16 | si_l) << 2, 27);
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return 0;
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case bl_op:
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*next_addr = pc + sign_extend64((si_h << 16 | si_l) << 2, 27);
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regs->regs[1] = pc + LOONGARCH_INSN_SIZE;
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return 0;
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}
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rj = ip->reg1i21_format.rj;
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cj = (rj & 0x07) + DBG_FCC_BASE;
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si_l = ip->reg1i21_format.immediate_l;
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si_h = ip->reg1i21_format.immediate_h;
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dbg_get_reg(cj, &cj_val, regs);
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switch (ip->reg1i21_format.opcode) {
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case beqz_op:
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if (regs->regs[rj] == 0)
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*next_addr = pc + sign_extend64((si_h << 16 | si_l) << 2, 22);
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return 0;
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case bnez_op:
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if (regs->regs[rj] != 0)
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*next_addr = pc + sign_extend64((si_h << 16 | si_l) << 2, 22);
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return 0;
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case bceqz_op: /* bceqz_op = bcnez_op */
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if (((rj & 0x18) == 0x00) && !cj_val) /* bceqz */
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*next_addr = pc + sign_extend64((si_h << 16 | si_l) << 2, 22);
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if (((rj & 0x18) == 0x08) && cj_val) /* bcnez */
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*next_addr = pc + sign_extend64((si_h << 16 | si_l) << 2, 22);
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return 0;
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}
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rj = ip->reg2i16_format.rj;
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rd = ip->reg2i16_format.rd;
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si = ip->reg2i16_format.immediate;
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switch (ip->reg2i16_format.opcode) {
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case beq_op:
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if (regs->regs[rj] == regs->regs[rd])
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*next_addr = pc + sign_extend64(si << 2, 17);
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return 0;
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case bne_op:
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if (regs->regs[rj] != regs->regs[rd])
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*next_addr = pc + sign_extend64(si << 2, 17);
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return 0;
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case blt_op:
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if ((long)regs->regs[rj] < (long)regs->regs[rd])
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*next_addr = pc + sign_extend64(si << 2, 17);
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return 0;
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case bge_op:
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if ((long)regs->regs[rj] >= (long)regs->regs[rd])
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*next_addr = pc + sign_extend64(si << 2, 17);
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return 0;
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case bltu_op:
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if (regs->regs[rj] < regs->regs[rd])
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*next_addr = pc + sign_extend64(si << 2, 17);
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return 0;
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case bgeu_op:
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if (regs->regs[rj] >= regs->regs[rd])
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*next_addr = pc + sign_extend64(si << 2, 17);
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return 0;
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case jirl_op:
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regs->regs[rd] = pc + LOONGARCH_INSN_SIZE;
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*next_addr = regs->regs[rj] + sign_extend64(si << 2, 17);
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return 0;
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}
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return 0;
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}
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static int do_single_step(struct pt_regs *regs)
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{
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int error = 0;
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unsigned long addr = 0; /* Determine where the target instruction will send us to */
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error = get_step_address(regs, &addr);
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if (error)
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return error;
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/* Store the opcode in the stepped address */
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error = get_kernel_nofault(stepped_opcode, (void *)addr);
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if (error)
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return error;
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stepped_address = addr;
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/* Replace the opcode with the break instruction */
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error = copy_to_kernel_nofault((void *)stepped_address,
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arch_kgdb_ops.gdb_bpt_instr, BREAK_INSTR_SIZE);
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flush_icache_range(addr, addr + BREAK_INSTR_SIZE);
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if (error) {
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stepped_opcode = 0;
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stepped_address = 0;
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} else {
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kgdb_single_step = 1;
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atomic_set(&kgdb_cpu_doing_single_step, raw_smp_processor_id());
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}
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return error;
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}
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/* Undo a single step */
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static void undo_single_step(struct pt_regs *regs)
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{
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if (stepped_opcode) {
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copy_to_kernel_nofault((void *)stepped_address,
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(void *)&stepped_opcode, BREAK_INSTR_SIZE);
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flush_icache_range(stepped_address, stepped_address + BREAK_INSTR_SIZE);
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}
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stepped_opcode = 0;
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stepped_address = 0;
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kgdb_single_step = 0;
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atomic_set(&kgdb_cpu_doing_single_step, -1);
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}
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int kgdb_arch_handle_exception(int vector, int signo, int err_code,
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char *remcom_in_buffer, char *remcom_out_buffer,
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struct pt_regs *regs)
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{
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int ret = 0;
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undo_single_step(regs);
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regs->csr_prmd |= CSR_PRMD_PWE;
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|
|
|
switch (remcom_in_buffer[0]) {
|
|
case 'D':
|
|
case 'k':
|
|
regs->csr_prmd &= ~CSR_PRMD_PWE;
|
|
fallthrough;
|
|
case 'c':
|
|
kgdb_arch_update_addr(regs, remcom_in_buffer);
|
|
break;
|
|
case 's':
|
|
kgdb_arch_update_addr(regs, remcom_in_buffer);
|
|
ret = do_single_step(regs);
|
|
break;
|
|
default:
|
|
ret = -1;
|
|
}
|
|
|
|
return ret;
|
|
}
|
|
|
|
static struct hw_breakpoint {
|
|
unsigned int enabled;
|
|
unsigned long addr;
|
|
int len;
|
|
int type;
|
|
struct perf_event * __percpu *pev;
|
|
} breakinfo[LOONGARCH_MAX_BRP];
|
|
|
|
static int hw_break_reserve_slot(int breakno)
|
|
{
|
|
int cpu, cnt = 0;
|
|
struct perf_event **pevent;
|
|
|
|
for_each_online_cpu(cpu) {
|
|
cnt++;
|
|
pevent = per_cpu_ptr(breakinfo[breakno].pev, cpu);
|
|
if (dbg_reserve_bp_slot(*pevent))
|
|
goto fail;
|
|
}
|
|
|
|
return 0;
|
|
|
|
fail:
|
|
for_each_online_cpu(cpu) {
|
|
cnt--;
|
|
if (!cnt)
|
|
break;
|
|
pevent = per_cpu_ptr(breakinfo[breakno].pev, cpu);
|
|
dbg_release_bp_slot(*pevent);
|
|
}
|
|
|
|
return -1;
|
|
}
|
|
|
|
static int hw_break_release_slot(int breakno)
|
|
{
|
|
int cpu;
|
|
struct perf_event **pevent;
|
|
|
|
if (dbg_is_early)
|
|
return 0;
|
|
|
|
for_each_online_cpu(cpu) {
|
|
pevent = per_cpu_ptr(breakinfo[breakno].pev, cpu);
|
|
if (dbg_release_bp_slot(*pevent))
|
|
/*
|
|
* The debugger is responsible for handing the retry on
|
|
* remove failure.
|
|
*/
|
|
return -1;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int kgdb_set_hw_break(unsigned long addr, int len, enum kgdb_bptype bptype)
|
|
{
|
|
int i;
|
|
|
|
for (i = 0; i < LOONGARCH_MAX_BRP; i++)
|
|
if (!breakinfo[i].enabled)
|
|
break;
|
|
|
|
if (i == LOONGARCH_MAX_BRP)
|
|
return -1;
|
|
|
|
switch (bptype) {
|
|
case BP_HARDWARE_BREAKPOINT:
|
|
breakinfo[i].type = HW_BREAKPOINT_X;
|
|
break;
|
|
case BP_READ_WATCHPOINT:
|
|
breakinfo[i].type = HW_BREAKPOINT_R;
|
|
break;
|
|
case BP_WRITE_WATCHPOINT:
|
|
breakinfo[i].type = HW_BREAKPOINT_W;
|
|
break;
|
|
case BP_ACCESS_WATCHPOINT:
|
|
breakinfo[i].type = HW_BREAKPOINT_RW;
|
|
break;
|
|
default:
|
|
return -1;
|
|
}
|
|
|
|
switch (len) {
|
|
case 1:
|
|
breakinfo[i].len = HW_BREAKPOINT_LEN_1;
|
|
break;
|
|
case 2:
|
|
breakinfo[i].len = HW_BREAKPOINT_LEN_2;
|
|
break;
|
|
case 4:
|
|
breakinfo[i].len = HW_BREAKPOINT_LEN_4;
|
|
break;
|
|
case 8:
|
|
breakinfo[i].len = HW_BREAKPOINT_LEN_8;
|
|
break;
|
|
default:
|
|
return -1;
|
|
}
|
|
|
|
breakinfo[i].addr = addr;
|
|
if (hw_break_reserve_slot(i)) {
|
|
breakinfo[i].addr = 0;
|
|
return -1;
|
|
}
|
|
breakinfo[i].enabled = 1;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int kgdb_remove_hw_break(unsigned long addr, int len, enum kgdb_bptype bptype)
|
|
{
|
|
int i;
|
|
|
|
for (i = 0; i < LOONGARCH_MAX_BRP; i++)
|
|
if (breakinfo[i].addr == addr && breakinfo[i].enabled)
|
|
break;
|
|
|
|
if (i == LOONGARCH_MAX_BRP)
|
|
return -1;
|
|
|
|
if (hw_break_release_slot(i)) {
|
|
pr_err("Cannot remove hw breakpoint at %lx\n", addr);
|
|
return -1;
|
|
}
|
|
breakinfo[i].enabled = 0;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static void kgdb_disable_hw_break(struct pt_regs *regs)
|
|
{
|
|
int i;
|
|
int cpu = raw_smp_processor_id();
|
|
struct perf_event *bp;
|
|
|
|
for (i = 0; i < LOONGARCH_MAX_BRP; i++) {
|
|
if (!breakinfo[i].enabled)
|
|
continue;
|
|
|
|
bp = *per_cpu_ptr(breakinfo[i].pev, cpu);
|
|
if (bp->attr.disabled == 1)
|
|
continue;
|
|
|
|
arch_uninstall_hw_breakpoint(bp);
|
|
bp->attr.disabled = 1;
|
|
}
|
|
|
|
/* Disable hardware debugging while we are in kgdb */
|
|
csr_xchg32(0, CSR_CRMD_WE, LOONGARCH_CSR_CRMD);
|
|
}
|
|
|
|
static void kgdb_remove_all_hw_break(void)
|
|
{
|
|
int i;
|
|
int cpu = raw_smp_processor_id();
|
|
struct perf_event *bp;
|
|
|
|
for (i = 0; i < LOONGARCH_MAX_BRP; i++) {
|
|
if (!breakinfo[i].enabled)
|
|
continue;
|
|
|
|
bp = *per_cpu_ptr(breakinfo[i].pev, cpu);
|
|
if (!bp->attr.disabled) {
|
|
arch_uninstall_hw_breakpoint(bp);
|
|
bp->attr.disabled = 1;
|
|
continue;
|
|
}
|
|
|
|
if (hw_break_release_slot(i))
|
|
pr_err("KGDB: hw bpt remove failed %lx\n", breakinfo[i].addr);
|
|
breakinfo[i].enabled = 0;
|
|
}
|
|
|
|
csr_xchg32(0, CSR_CRMD_WE, LOONGARCH_CSR_CRMD);
|
|
kgdb_watch_activated = 0;
|
|
}
|
|
|
|
static void kgdb_correct_hw_break(void)
|
|
{
|
|
int i, activated = 0;
|
|
|
|
for (i = 0; i < LOONGARCH_MAX_BRP; i++) {
|
|
struct perf_event *bp;
|
|
int val;
|
|
int cpu = raw_smp_processor_id();
|
|
|
|
if (!breakinfo[i].enabled)
|
|
continue;
|
|
|
|
bp = *per_cpu_ptr(breakinfo[i].pev, cpu);
|
|
if (bp->attr.disabled != 1)
|
|
continue;
|
|
|
|
bp->attr.bp_addr = breakinfo[i].addr;
|
|
bp->attr.bp_len = breakinfo[i].len;
|
|
bp->attr.bp_type = breakinfo[i].type;
|
|
|
|
val = hw_breakpoint_arch_parse(bp, &bp->attr, counter_arch_bp(bp));
|
|
if (val)
|
|
return;
|
|
|
|
val = arch_install_hw_breakpoint(bp);
|
|
if (!val)
|
|
bp->attr.disabled = 0;
|
|
activated = 1;
|
|
}
|
|
|
|
csr_xchg32(activated ? CSR_CRMD_WE : 0, CSR_CRMD_WE, LOONGARCH_CSR_CRMD);
|
|
kgdb_watch_activated = activated;
|
|
}
|
|
|
|
const struct kgdb_arch arch_kgdb_ops = {
|
|
.gdb_bpt_instr = {0x02, 0x00, break_op >> 1, 0x00}, /* BRK_KDB = 2 */
|
|
.flags = KGDB_HW_BREAKPOINT,
|
|
.set_hw_breakpoint = kgdb_set_hw_break,
|
|
.remove_hw_breakpoint = kgdb_remove_hw_break,
|
|
.disable_hw_break = kgdb_disable_hw_break,
|
|
.remove_all_hw_break = kgdb_remove_all_hw_break,
|
|
.correct_hw_break = kgdb_correct_hw_break,
|
|
};
|
|
|
|
int kgdb_arch_init(void)
|
|
{
|
|
return register_die_notifier(&kgdb_notifier);
|
|
}
|
|
|
|
void kgdb_arch_late(void)
|
|
{
|
|
int i, cpu;
|
|
struct perf_event_attr attr;
|
|
struct perf_event **pevent;
|
|
|
|
hw_breakpoint_init(&attr);
|
|
|
|
attr.bp_addr = (unsigned long)kgdb_arch_init;
|
|
attr.bp_len = HW_BREAKPOINT_LEN_4;
|
|
attr.bp_type = HW_BREAKPOINT_W;
|
|
attr.disabled = 1;
|
|
|
|
for (i = 0; i < LOONGARCH_MAX_BRP; i++) {
|
|
if (breakinfo[i].pev)
|
|
continue;
|
|
|
|
breakinfo[i].pev = register_wide_hw_breakpoint(&attr, NULL, NULL);
|
|
if (IS_ERR((void * __force)breakinfo[i].pev)) {
|
|
pr_err("kgdb: Could not allocate hw breakpoints.\n");
|
|
breakinfo[i].pev = NULL;
|
|
return;
|
|
}
|
|
|
|
for_each_online_cpu(cpu) {
|
|
pevent = per_cpu_ptr(breakinfo[i].pev, cpu);
|
|
if (pevent[0]->destroy) {
|
|
pevent[0]->destroy = NULL;
|
|
release_bp_slot(*pevent);
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
void kgdb_arch_exit(void)
|
|
{
|
|
int i;
|
|
|
|
for (i = 0; i < LOONGARCH_MAX_BRP; i++) {
|
|
if (breakinfo[i].pev) {
|
|
unregister_wide_hw_breakpoint(breakinfo[i].pev);
|
|
breakinfo[i].pev = NULL;
|
|
}
|
|
}
|
|
|
|
unregister_die_notifier(&kgdb_notifier);
|
|
}
|