From e2fdd7fd99dd68b77caaf2a2272b75b5da890de7 Mon Sep 17 00:00:00 2001 From: "David S. Miller" Date: Tue, 29 Apr 2008 02:38:50 -0700 Subject: sparc: Add kgdb support. Current limitations: 1) On SMP single stepping has some fundamental issues, shared with other sw single-step architectures such as mips and arm. 2) On 32-bit sparc we don't support SMP kgdb yet. That requires some reworking of the IPI mechanisms and infrastructure on that platform. Signed-off-by: David S. Miller --- arch/sparc64/kernel/Makefile | 1 + arch/sparc64/kernel/kgdb.c | 186 +++++++++++++++++++++++++++++++++++++++++ arch/sparc64/kernel/misctrap.S | 10 +++ arch/sparc64/kernel/smp.c | 10 +++ arch/sparc64/kernel/ttable.S | 2 +- 5 files changed, 208 insertions(+), 1 deletion(-) create mode 100644 arch/sparc64/kernel/kgdb.c (limited to 'arch/sparc64/kernel') diff --git a/arch/sparc64/kernel/Makefile b/arch/sparc64/kernel/Makefile index 2bd0340b743..ec4f5ebb1ca 100644 --- a/arch/sparc64/kernel/Makefile +++ b/arch/sparc64/kernel/Makefile @@ -29,3 +29,4 @@ obj-$(CONFIG_SUN_LDOMS) += ldc.o vio.o viohs.o ds.o obj-$(CONFIG_AUDIT) += audit.o obj-$(CONFIG_AUDIT)$(CONFIG_COMPAT) += compat_audit.o obj-y += $(obj-yy) +obj-$(CONFIG_KGDB) += kgdb.o diff --git a/arch/sparc64/kernel/kgdb.c b/arch/sparc64/kernel/kgdb.c new file mode 100644 index 00000000000..fefbe6dc51b --- /dev/null +++ b/arch/sparc64/kernel/kgdb.c @@ -0,0 +1,186 @@ +/* kgdb.c: KGDB support for 64-bit sparc. + * + * Copyright (C) 2008 David S. Miller + */ + +#include +#include + +#include +#include +#include + +void pt_regs_to_gdb_regs(unsigned long *gdb_regs, struct pt_regs *regs) +{ + struct reg_window *win; + int i; + + gdb_regs[GDB_G0] = 0; + for (i = 0; i < 15; i++) + gdb_regs[GDB_G1 + i] = regs->u_regs[UREG_G1 + i]; + + win = (struct reg_window *) (regs->u_regs[UREG_FP] + STACK_BIAS); + for (i = 0; i < 8; i++) + gdb_regs[GDB_L0 + i] = win->locals[i]; + for (i = 0; i < 8; i++) + gdb_regs[GDB_I0 + i] = win->ins[i]; + + for (i = GDB_F0; i <= GDB_F62; i++) + gdb_regs[i] = 0; + + gdb_regs[GDB_PC] = regs->tpc; + gdb_regs[GDB_NPC] = regs->tnpc; + gdb_regs[GDB_STATE] = regs->tstate; + gdb_regs[GDB_FSR] = 0; + gdb_regs[GDB_FPRS] = 0; + gdb_regs[GDB_Y] = regs->y; +} + +void sleeping_thread_to_gdb_regs(unsigned long *gdb_regs, struct task_struct *p) +{ + struct thread_info *t = task_thread_info(p); + extern unsigned int switch_to_pc; + extern unsigned int ret_from_syscall; + struct reg_window *win; + unsigned long pc, cwp; + int i; + + for (i = GDB_G0; i < GDB_G6; i++) + gdb_regs[i] = 0; + gdb_regs[GDB_G6] = (unsigned long) t; + gdb_regs[GDB_G7] = (unsigned long) p; + for (i = GDB_O0; i < GDB_SP; i++) + gdb_regs[i] = 0; + gdb_regs[GDB_SP] = t->ksp; + gdb_regs[GDB_O7] = 0; + + win = (struct reg_window *) (t->ksp + STACK_BIAS); + for (i = 0; i < 8; i++) + gdb_regs[GDB_L0 + i] = win->locals[i]; + for (i = 0; i < 8; i++) + gdb_regs[GDB_I0 + i] = win->ins[i]; + + for (i = GDB_F0; i <= GDB_F62; i++) + gdb_regs[i] = 0; + + if (t->new_child) + pc = (unsigned long) &ret_from_syscall; + else + pc = (unsigned long) &switch_to_pc; + + gdb_regs[GDB_PC] = pc; + gdb_regs[GDB_NPC] = pc + 4; + + cwp = __thread_flag_byte_ptr(t)[TI_FLAG_BYTE_CWP]; + + gdb_regs[GDB_STATE] = (TSTATE_PRIV | TSTATE_IE | cwp); + gdb_regs[GDB_FSR] = 0; + gdb_regs[GDB_FPRS] = 0; + gdb_regs[GDB_Y] = 0; +} + +void gdb_regs_to_pt_regs(unsigned long *gdb_regs, struct pt_regs *regs) +{ + struct reg_window *win; + int i; + + for (i = 0; i < 15; i++) + regs->u_regs[UREG_G1 + i] = gdb_regs[GDB_G1 + i]; + + /* If the TSTATE register is changing, we have to preserve + * the CWP field, otherwise window save/restore explodes. + */ + if (regs->tstate != gdb_regs[GDB_STATE]) { + unsigned long cwp = regs->tstate & TSTATE_CWP; + + regs->tstate = (gdb_regs[GDB_STATE] & ~TSTATE_CWP) | cwp; + } + + regs->tpc = gdb_regs[GDB_PC]; + regs->tnpc = gdb_regs[GDB_NPC]; + regs->y = gdb_regs[GDB_Y]; + + win = (struct reg_window *) (regs->u_regs[UREG_FP] + STACK_BIAS); + for (i = 0; i < 8; i++) + win->locals[i] = gdb_regs[GDB_L0 + i]; + for (i = 0; i < 8; i++) + win->ins[i] = gdb_regs[GDB_I0 + i]; +} + +#ifdef CONFIG_SMP +void smp_kgdb_capture_client(struct pt_regs *regs) +{ + unsigned long flags; + + __asm__ __volatile__("rdpr %%pstate, %0\n\t" + "wrpr %0, %1, %%pstate" + : "=r" (flags) + : "i" (PSTATE_IE)); + + flushw_all(); + + if (atomic_read(&kgdb_active) != -1) + kgdb_nmicallback(raw_smp_processor_id(), regs); + + __asm__ __volatile__("wrpr %0, 0, %%pstate" + : : "r" (flags)); +} +#endif + +int kgdb_arch_handle_exception(int e_vector, int signo, int err_code, + char *remcomInBuffer, char *remcomOutBuffer, + struct pt_regs *linux_regs) +{ + unsigned long addr; + char *ptr; + + switch (remcomInBuffer[0]) { + case 'c': + /* try to read optional parameter, pc unchanged if no parm */ + ptr = &remcomInBuffer[1]; + if (kgdb_hex2long(&ptr, &addr)) { + linux_regs->tpc = addr; + linux_regs->tnpc = addr + 4; + } + /* fallthru */ + + case 'D': + case 'k': + if (linux_regs->tpc == (unsigned long) arch_kgdb_breakpoint) { + linux_regs->tpc = linux_regs->tnpc; + linux_regs->tnpc += 4; + } + return 0; + } + return -1; +} + +asmlinkage void kgdb_trap(unsigned long trap_level, struct pt_regs *regs) +{ + unsigned long flags; + + if (user_mode(regs)) { + bad_trap(regs, trap_level); + return; + } + + flushw_all(); + + local_irq_save(flags); + kgdb_handle_exception(0x172, SIGTRAP, 0, regs); + local_irq_restore(flags); +} + +int kgdb_arch_init(void) +{ + return 0; +} + +void kgdb_arch_exit(void) +{ +} + +struct kgdb_arch arch_kgdb_ops = { + /* Breakpoint instruction: ta 0x72 */ + .gdb_bpt_instr = { 0x91, 0xd0, 0x20, 0x72 }, +}; diff --git a/arch/sparc64/kernel/misctrap.S b/arch/sparc64/kernel/misctrap.S index b257497ddde..753b4f031bf 100644 --- a/arch/sparc64/kernel/misctrap.S +++ b/arch/sparc64/kernel/misctrap.S @@ -1,3 +1,13 @@ +#ifdef CONFIG_KGDB + .globl arch_kgdb_breakpoint + .type arch_kgdb_breakpoint,#function +arch_kgdb_breakpoint: + ta 0x72 + retl + nop + .size arch_kgdb_breakpoint,.-arch_kgdb_breakpoint +#endif + .type __do_privact,#function __do_privact: mov TLB_SFSR, %g3 diff --git a/arch/sparc64/kernel/smp.c b/arch/sparc64/kernel/smp.c index 409dd71f273..8face0c49fe 100644 --- a/arch/sparc64/kernel/smp.c +++ b/arch/sparc64/kernel/smp.c @@ -910,6 +910,9 @@ extern unsigned long xcall_flush_tlb_kernel_range; extern unsigned long xcall_report_regs; extern unsigned long xcall_receive_signal; extern unsigned long xcall_new_mmu_context_version; +#ifdef CONFIG_KGDB +extern unsigned long xcall_kgdb_capture; +#endif #ifdef DCACHE_ALIASING_POSSIBLE extern unsigned long xcall_flush_dcache_page_cheetah; @@ -1079,6 +1082,13 @@ void smp_new_mmu_context_version(void) smp_cross_call(&xcall_new_mmu_context_version, 0, 0, 0); } +#ifdef CONFIG_KGDB +void kgdb_roundup_cpus(unsigned long flags) +{ + smp_cross_call(&xcall_kgdb_capture, 0, 0, 0); +} +#endif + void smp_report_regs(void) { smp_cross_call(&xcall_report_regs, 0, 0, 0); diff --git a/arch/sparc64/kernel/ttable.S b/arch/sparc64/kernel/ttable.S index b0de4c00b11..450053af039 100644 --- a/arch/sparc64/kernel/ttable.S +++ b/arch/sparc64/kernel/ttable.S @@ -153,7 +153,7 @@ tl0_resv164: BTRAP(0x164) BTRAP(0x165) BTRAP(0x166) BTRAP(0x167) BTRAP(0x168) tl0_resv169: BTRAP(0x169) BTRAP(0x16a) BTRAP(0x16b) BTRAP(0x16c) tl0_linux64: LINUX_64BIT_SYSCALL_TRAP tl0_gsctx: TRAP(sparc64_get_context) TRAP(sparc64_set_context) -tl0_resv170: KPROBES_TRAP(0x170) KPROBES_TRAP(0x171) BTRAP(0x172) +tl0_resv170: KPROBES_TRAP(0x170) KPROBES_TRAP(0x171) KGDB_TRAP(0x172) tl0_resv173: BTRAP(0x173) BTRAP(0x174) BTRAP(0x175) BTRAP(0x176) BTRAP(0x177) tl0_resv178: BTRAP(0x178) BTRAP(0x179) BTRAP(0x17a) BTRAP(0x17b) BTRAP(0x17c) tl0_resv17d: BTRAP(0x17d) BTRAP(0x17e) BTRAP(0x17f) -- cgit v1.2.3-18-g5258