[PATCH 5/23] Make register values available to Blackfin panicnotifiers
From: David VomLehn
Date: Mon Apr 12 2010 - 02:06:39 EST
The save_ptregs() functions compiles cleanly, but has not been tested.
Signed-off-by: David VomLehn <dvomlehn@xxxxxxxxx>
---
arch/blackfin/include/asm/blackfin.h | 10 +-
arch/blackfin/include/asm/ptrace.h | 187 ++++++++++++++++++++++++++++++++++
arch/blackfin/kernel/traps.c | 8 +-
3 files changed, 196 insertions(+), 9 deletions(-)
diff --git a/arch/blackfin/include/asm/blackfin.h b/arch/blackfin/include/asm/blackfin.h
index eb7c144..9cfa5cc 100644
--- a/arch/blackfin/include/asm/blackfin.h
+++ b/arch/blackfin/include/asm/blackfin.h
@@ -11,6 +11,11 @@
#include <mach/anomaly.h>
+#define LO(con32) ((con32) & 0xFFFF)
+#define lo(con32) ((con32) & 0xFFFF)
+#define HI(con32) (((con32) >> 16) & 0xFFFF)
+#define hi(con32) (((con32) >> 16) & 0xFFFF)
+
#ifndef __ASSEMBLY__
/* SSYNC implementation for C file */
@@ -63,11 +68,6 @@ static inline void CSYNC(void)
#else /* __ASSEMBLY__ */
-#define LO(con32) ((con32) & 0xFFFF)
-#define lo(con32) ((con32) & 0xFFFF)
-#define HI(con32) (((con32) >> 16) & 0xFFFF)
-#define hi(con32) (((con32) >> 16) & 0xFFFF)
-
/* SSYNC & CSYNC implementations for assembly files */
#define ssync(x) SSYNC(x)
diff --git a/arch/blackfin/include/asm/ptrace.h b/arch/blackfin/include/asm/ptrace.h
index aaa1c6c..8bb8012 100644
--- a/arch/blackfin/include/asm/ptrace.h
+++ b/arch/blackfin/include/asm/ptrace.h
@@ -127,6 +127,193 @@ extern void user_disable_single_step(struct task_struct *child);
((unsigned long)task_stack_page(task) + \
(THREAD_SIZE - sizeof(struct pt_regs)))
+/* Macros for saving the contents of registers and for the output constraint
+ * for those registers */
+#include <linux/ptreg.h>
+#include <asm/blackfin.h>
+
+#define STR(x) #x
+#define VAL(x) STR(x)
+
+#define PTREG_SAVE(r, name) "%[" #name "] = " #r "\n"
+
+/*
+ * The following is used for cases where the register can't be saved
+ * directly, but must first be moved to another register that can be
+ * saved directly. The second register must already have been saved
+ * by the time this macro is used.
+ */
+#define PTREG_INDIRECT_SAVE(tmp_r, r, name) \
+ #tmp_r " = " #r "\n" \
+ PTREG_SAVE(tmp_r, name)
+
+#define PTREG_SAVE_LB(i) _PTREG_INDIRECT_SAVE_I(R0, LB, lb, i)
+#define PTREG_SAVE_LT(i) _PTREG_INDIRECT_SAVE_I(R0, LT, lt, i)
+#define PTREG_SAVE_LC(i) _PTREG_INDIRECT_SAVE_I(R0, LC, lc, i)
+#define PTREG_SAVE_B(i) _PTREG_INDIRECT_SAVE_I(R0, B, b, i)
+#define PTREG_SAVE_L(i) _PTREG_INDIRECT_SAVE_I(R0, L, l, i)
+#define PTREG_SAVE_M(i) _PTREG_INDIRECT_SAVE_I(R0, M, m, i)
+#define PTREG_SAVE_I(_i) _PTREG_INDIRECT_SAVE_I(R0, I, i, _i)
+#define PTREG_SAVE_P(i) _PTREG_SAVE_I(P, p, i)
+#define PTREG_SAVE_R(i) _PTREG_SAVE_I(R, r, i)
+
+#define PTREG_OUT_LB(regs, i) _PTREG_OUT_I(regs, lb, lb, i)
+#define PTREG_OUT_LT(regs, i) _PTREG_OUT_I(regs, lt, lt, i)
+#define PTREG_OUT_LC(regs, i) _PTREG_OUT_I(regs, lc, lc, i)
+#define PTREG_OUT_B(regs, i) _PTREG_OUT_I(regs, b, b, i)
+#define PTREG_OUT_L(regs, i) _PTREG_OUT_I(regs, l, l, i)
+#define PTREG_OUT_M(regs, i) _PTREG_OUT_I(regs, m, m, i)
+#define PTREG_OUT_I(regs, _i) _PTREG_OUT_I(regs, i, i, _i)
+#define PTREG_OUT_P(regs, i) _PTREG_OUT_I(regs, p, p, i)
+#define PTREG_OUT_R(regs, i) _PTREG_OUT_I(regs, r, r, i)
+
+#define arch_has_save_ptregs 1
+
+/**
+ * save_ptregs - save processor registers for backtracing
+ * @regs: Pointer to &struct pt_regs structure in which to save the
+ * registers
+ *
+ * Returns a constant pointer to @regs.
+ *
+ * This function must be called first in a function. There must be no
+ * auto variables defined that are initialized before calling this function.
+ */
+static __always_inline
+const struct pt_regs *save_ptregs(struct pt_regs *regs)
+{
+ __asm__ __volatile__ (
+ /* Save the Dregs and Pregs first because we may
+ * use them to save other registers */
+ PTREG_SAVE_R(7)
+ PTREG_SAVE_R(6)
+ PTREG_SAVE_R(5)
+ PTREG_SAVE_R(4)
+ PTREG_SAVE_R(3)
+ PTREG_SAVE_R(2)
+ PTREG_SAVE_R(1)
+ PTREG_SAVE_R(0)
+ PTREG_SAVE_P(5)
+ PTREG_SAVE_P(4)
+ PTREG_SAVE_P(3)
+ PTREG_SAVE_P(2)
+ PTREG_SAVE_P(1)
+ PTREG_SAVE_P(0)
+
+ /* Now all of the Dregs and Pregs can be used for
+ * saving other registers. Just be sure to add them
+ * to the clobbered list */
+
+ "p0.l = " VAL(lo(IPEND)) "\n"
+ "p0.h = " VAL(hi(IPEND)) "\n"
+ PTREG_SAVE(p0, ipend)
+ PTREG_INDIRECT_SAVE(R0, seqstat, seqstat)
+ PTREG_INDIRECT_SAVE(R0, rete, rete)
+ PTREG_INDIRECT_SAVE(R0, retn, retn)
+ PTREG_INDIRECT_SAVE(R0, retx, retx)
+ PTREG_INDIRECT_SAVE(R0, rets, rets)
+ PTREG_INDIRECT_SAVE(R0, astat, astat)
+ PTREG_SAVE_LB(1)
+ PTREG_SAVE_LB(0)
+ PTREG_SAVE_LT(1)
+ PTREG_SAVE_LT(0)
+ PTREG_SAVE_LC(1)
+ PTREG_SAVE_LC(0)
+
+ :
+ PTREG_OUT_R(regs, 7),
+ PTREG_OUT_R(regs, 6),
+ PTREG_OUT_R(regs, 5),
+ PTREG_OUT_R(regs, 4),
+ PTREG_OUT_R(regs, 3),
+ PTREG_OUT_R(regs, 2),
+ PTREG_OUT_R(regs, 1),
+ PTREG_OUT_R(regs, 0),
+ PTREG_OUT_P(regs, 5),
+ PTREG_OUT_P(regs, 4),
+ PTREG_OUT_P(regs, 3),
+ PTREG_OUT_P(regs, 2),
+ PTREG_OUT_P(regs, 1),
+ PTREG_OUT_P(regs, 0),
+ PTREG_OUT(regs, ipend, ipend),
+ PTREG_OUT(regs, seqstat, seqstat),
+ PTREG_OUT(regs, rete, rete),
+ PTREG_OUT(regs, retn, retn),
+ PTREG_OUT(regs, retx, retx),
+ PTREG_OUT(regs, rets, rets),
+ PTREG_OUT(regs, astat, astat),
+ PTREG_OUT_LB(regs, 1),
+ PTREG_OUT_LB(regs, 0),
+ PTREG_OUT_LT(regs, 1),
+ PTREG_OUT_LT(regs, 0),
+ PTREG_OUT_LC(regs, 1),
+ PTREG_OUT_LC(regs, 0)
+ :
+ :
+ "R0", "P0"
+ );
+ __asm__ __volatile__ (
+ PTREG_INDIRECT_SAVE(R0, A1.W, a1w)
+ PTREG_INDIRECT_SAVE(R0, A1.X, a1x)
+ PTREG_INDIRECT_SAVE(R0, A0.W, a0w)
+ PTREG_INDIRECT_SAVE(R0, A0.X, a0x)
+ PTREG_SAVE_B(3)
+ PTREG_SAVE_B(2)
+ PTREG_SAVE_B(1)
+ PTREG_SAVE_B(0)
+ PTREG_SAVE_L(3)
+ PTREG_SAVE_L(2)
+ PTREG_SAVE_L(1)
+ PTREG_SAVE_L(0)
+ PTREG_SAVE_M(3)
+ PTREG_SAVE_M(2)
+ PTREG_SAVE_M(1)
+ PTREG_SAVE_M(0)
+ PTREG_SAVE_I(3)
+ PTREG_SAVE_I(2)
+ PTREG_SAVE_I(1)
+ PTREG_SAVE_I(0)
+ PTREG_INDIRECT_SAVE(R0, USP, usp)
+ PTREG_INDIRECT_SAVE(R0, FP, fp)
+ PTREG_INDIRECT_SAVE(R0, SYSCFG, syscfg)
+ "1:\n"
+ /* We've saved P0 already, so we can use it go set
+ * the pc */
+ "P0.h = 1b\n"
+ "P0.l = 1b\n"
+ PTREG_SAVE(P0, pc)
+ :
+ PTREG_OUT(regs, a1w, a1w),
+ PTREG_OUT(regs, a1x, a1x),
+ PTREG_OUT(regs, a0w, a0w),
+ PTREG_OUT(regs, a0x, a0x),
+ PTREG_OUT_B(regs, 3),
+ PTREG_OUT_B(regs, 2),
+ PTREG_OUT_B(regs, 1),
+ PTREG_OUT_B(regs, 0),
+ PTREG_OUT_L(regs, 3),
+ PTREG_OUT_L(regs, 2),
+ PTREG_OUT_L(regs, 1),
+ PTREG_OUT_L(regs, 0),
+ PTREG_OUT_M(regs, 3),
+ PTREG_OUT_M(regs, 2),
+ PTREG_OUT_M(regs, 1),
+ PTREG_OUT_M(regs, 0),
+ PTREG_OUT_I(regs, 3),
+ PTREG_OUT_I(regs, 2),
+ PTREG_OUT_I(regs, 1),
+ PTREG_OUT_I(regs, 0),
+ PTREG_OUT(regs, usp, usp),
+ PTREG_OUT(regs, fp, fp),
+ PTREG_OUT(regs, syscfg, syscfg),
+ PTREG_OUT(regs, pc, pc)
+ :
+ :
+ "R0", "P0"
+ );
+
+ return regs;
+}
#endif /* __KERNEL__ */
#endif /* __ASSEMBLY__ */
diff --git a/arch/blackfin/kernel/traps.c b/arch/blackfin/kernel/traps.c
index ba70c4b..44a709c 100644
--- a/arch/blackfin/kernel/traps.c
+++ b/arch/blackfin/kernel/traps.c
@@ -246,7 +246,7 @@ asmlinkage void double_fault_c(struct pt_regs *fp)
dump_bfin_trace_buffer();
}
#endif
- panic("Double Fault - unrecoverable event");
+ panic_with_regs(fp, "Double Fault - unrecoverable event");
}
@@ -388,7 +388,7 @@ asmlinkage notrace void trap_c(struct pt_regs *fp)
/* call to panic() will dump trace, and it is
* off at this point, so it won't be clobbered
*/
- panic("BUG()");
+ panic_with_regs(fp, "BUG()");
}
}
#endif
@@ -631,7 +631,7 @@ asmlinkage notrace void trap_c(struct pt_regs *fp)
verbose_printk(KERN_EMERG "Please turn on "
"CONFIG_ACCESS_CHECK\n");
#endif
- panic("Kernel exception");
+ panic_with_regs(fp, "Kernel exception");
} else {
#ifdef CONFIG_DEBUG_VERBOSE
unsigned long *stack;
@@ -1347,5 +1347,5 @@ void panic_cplb_error(int cplb_panic, struct pt_regs *fp)
dump_bfin_mem(fp);
show_regs(fp);
dump_stack();
- panic("Unrecoverable event");
+ panic_with_regs(fp, "Unrecoverable event");
}
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