kgdb,arm: Individual register get/set for arm

Implement the ability to individually get and set registers for kdb
and kgdb for arm.

Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
CC: Russell King <linux@arm.linux.org.uk>
CC: linux-arm-kernel@lists.infradead.org

2 files changed, 50 insertions, 46 deletions

diff --git a/arch/arm/include/asm/kgdb.h b/arch/arm/include/asm/kgdb.h
index 67af4b841984..08265993227f 100644
--- a/arch/arm/include/asm/kgdb.h
+++ b/arch/arm/include/asm/kgdb.h
@@ -70,11 +70,11 @@ extern int kgdb_fault_expected;
 #define _GP_REGS                16
 #define _FP_REGS                8
 #define _EXTRA_REGS             2
-#define GDB_MAX_REGS            (_GP_REGS + (_FP_REGS * 3) + _EXTRA_REGS)
+#define DBG_MAX_REG_NUM         (_GP_REGS + (_FP_REGS * 3) + _EXTRA_REGS)
 
 #define KGDB_MAX_NO_CPUS        1
 #define BUFMAX                  400
-#define NUMREGBYTES             (GDB_MAX_REGS << 2)
+#define NUMREGBYTES             (DBG_MAX_REG_NUM << 2)
 #define NUMCRITREGBYTES         (32 << 2)
 
 #define _R0                     0
@@ -93,7 +93,7 @@ extern int kgdb_fault_expected;
 #define _SPT                    13
 #define _LR                     14
 #define _PC                     15
-#define _CPSR                   (GDB_MAX_REGS - 1)
+#define _CPSR                   (DBG_MAX_REG_NUM - 1)
 
 /*
  * So that we can denote the end of a frame for tracing,
diff --git a/arch/arm/kernel/kgdb.c b/arch/arm/kernel/kgdb.c
index c868a8864117..cf846cade354 100644
--- a/arch/arm/kernel/kgdb.c
+++ b/arch/arm/kernel/kgdb.c
@@ -13,54 +13,58 @@
 #include <linux/kgdb.h>
 #include <asm/traps.h>
 
-/* Make a local copy of the registers passed into the handler (bletch) */
-void pt_regs_to_gdb_regs(unsigned long *gdb_regs, struct pt_regs *kernel_regs)
+struct dbg_reg_def_t dbg_reg_def[DBG_MAX_REG_NUM] =
 {
-        int regno;
-
-        /* Initialize all to zero. */
-        for (regno = 0; regno < GDB_MAX_REGS; regno++)
-                gdb_regs[regno] = 0;
+        { "r0", 4, offsetof(struct pt_regs, ARM_r0)},
+        { "r1", 4, offsetof(struct pt_regs, ARM_r1)},
+        { "r2", 4, offsetof(struct pt_regs, ARM_r2)},
+        { "r3", 4, offsetof(struct pt_regs, ARM_r3)},
+        { "r4", 4, offsetof(struct pt_regs, ARM_r4)},
+        { "r5", 4, offsetof(struct pt_regs, ARM_r5)},
+        { "r6", 4, offsetof(struct pt_regs, ARM_r6)},
+        { "r7", 4, offsetof(struct pt_regs, ARM_r7)},
+        { "r8", 4, offsetof(struct pt_regs, ARM_r8)},
+        { "r9", 4, offsetof(struct pt_regs, ARM_r9)},
+        { "r10", 4, offsetof(struct pt_regs, ARM_r10)},
+        { "fp", 4, offsetof(struct pt_regs, ARM_fp)},
+        { "ip", 4, offsetof(struct pt_regs, ARM_ip)},
+        { "sp", 4, offsetof(struct pt_regs, ARM_sp)},
+        { "lr", 4, offsetof(struct pt_regs, ARM_lr)},
+        { "pc", 4, offsetof(struct pt_regs, ARM_pc)},
+        { "f0", 12, -1 },
+        { "f1", 12, -1 },
+        { "f2", 12, -1 },
+        { "f3", 12, -1 },
+        { "f4", 12, -1 },
+        { "f5", 12, -1 },
+        { "f6", 12, -1 },
+        { "f7", 12, -1 },
+        { "fps", 4, -1 },
+        { "cpsr", 4, offsetof(struct pt_regs, ARM_cpsr)},
+};
 
-        gdb_regs[_R0]           = kernel_regs->ARM_r0;
-        gdb_regs[_R1]           = kernel_regs->ARM_r1;
-        gdb_regs[_R2]           = kernel_regs->ARM_r2;
-        gdb_regs[_R3]           = kernel_regs->ARM_r3;
-        gdb_regs[_R4]           = kernel_regs->ARM_r4;
-        gdb_regs[_R5]           = kernel_regs->ARM_r5;
-        gdb_regs[_R6]           = kernel_regs->ARM_r6;
-        gdb_regs[_R7]           = kernel_regs->ARM_r7;
-        gdb_regs[_R8]           = kernel_regs->ARM_r8;
-        gdb_regs[_R9]           = kernel_regs->ARM_r9;
-        gdb_regs[_R10]          = kernel_regs->ARM_r10;
-        gdb_regs[_FP]           = kernel_regs->ARM_fp;
-        gdb_regs[_IP]           = kernel_regs->ARM_ip;
-        gdb_regs[_SPT]          = kernel_regs->ARM_sp;
-        gdb_regs[_LR]           = kernel_regs->ARM_lr;
-        gdb_regs[_PC]           = kernel_regs->ARM_pc;
-        gdb_regs[_CPSR]         = kernel_regs->ARM_cpsr;
+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;
 }
 
-/* Copy local gdb registers back to kgdb regs, for later copy to kernel */
-void gdb_regs_to_pt_regs(unsigned long *gdb_regs, struct pt_regs *kernel_regs)
+int dbg_set_reg(int regno, void *mem, struct pt_regs *regs)
 {
-        kernel_regs->ARM_r0     = gdb_regs[_R0];
-        kernel_regs->ARM_r1     = gdb_regs[_R1];
-        kernel_regs->ARM_r2     = gdb_regs[_R2];
-        kernel_regs->ARM_r3     = gdb_regs[_R3];
-        kernel_regs->ARM_r4     = gdb_regs[_R4];
-        kernel_regs->ARM_r5     = gdb_regs[_R5];
-        kernel_regs->ARM_r6     = gdb_regs[_R6];
-        kernel_regs->ARM_r7     = gdb_regs[_R7];
-        kernel_regs->ARM_r8     = gdb_regs[_R8];
-        kernel_regs->ARM_r9     = gdb_regs[_R9];
-        kernel_regs->ARM_r10    = gdb_regs[_R10];
-        kernel_regs->ARM_fp     = gdb_regs[_FP];
-        kernel_regs->ARM_ip     = gdb_regs[_IP];
-        kernel_regs->ARM_sp     = gdb_regs[_SPT];
-        kernel_regs->ARM_lr     = gdb_regs[_LR];
-        kernel_regs->ARM_pc     = gdb_regs[_PC];
-        kernel_regs->ARM_cpsr   = gdb_regs[_CPSR];
+        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