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-rw-r--r--arch/blackfin/kernel/pseudodbg.c191
1 files changed, 191 insertions, 0 deletions
diff --git a/arch/blackfin/kernel/pseudodbg.c b/arch/blackfin/kernel/pseudodbg.c
new file mode 100644
index 00000000000..db85bc94334
--- /dev/null
+++ b/arch/blackfin/kernel/pseudodbg.c
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+/* The fake debug assert instructions
+ *
+ * Copyright 2010 Analog Devices Inc.
+ *
+ * Licensed under the GPL-2 or later
+ */
+
+#include <linux/types.h>
+#include <linux/kernel.h>
+#include <linux/ptrace.h>
+
+const char * const greg_names[] = {
+ "R0", "R1", "R2", "R3", "R4", "R5", "R6", "R7",
+ "P0", "P1", "P2", "P3", "P4", "P5", "SP", "FP",
+ "I0", "I1", "I2", "I3", "M0", "M1", "M2", "M3",
+ "B0", "B1", "B2", "B3", "L0", "L1", "L2", "L3",
+ "A0.X", "A0.W", "A1.X", "A1.W", "<res>", "<res>", "ASTAT", "RETS",
+ "<res>", "<res>", "<res>", "<res>", "<res>", "<res>", "<res>", "<res>",
+ "LC0", "LT0", "LB0", "LC1", "LT1", "LB1", "CYCLES", "CYCLES2",
+ "USP", "SEQSTAT", "SYSCFG", "RETI", "RETX", "RETN", "RETE", "EMUDAT",
+};
+
+static const char *get_allreg_name(int grp, int reg)
+{
+ return greg_names[(grp << 3) | reg];
+}
+
+/*
+ * Unfortunately, the pt_regs structure is not laid out the same way as the
+ * hardware register file, so we need to do some fix ups.
+ *
+ * CYCLES is not stored in the pt_regs structure - so, we just read it from
+ * the hardware.
+ *
+ * Don't support:
+ * - All reserved registers
+ * - All in group 7 are (supervisors only)
+ */
+
+static bool fix_up_reg(struct pt_regs *fp, long *value, int grp, int reg)
+{
+ long *val = &fp->r0;
+ unsigned long tmp;
+
+ /* Only do Dregs and Pregs for now */
+ if (grp == 5 ||
+ (grp == 4 && (reg == 4 || reg == 5)) ||
+ (grp == 7))
+ return false;
+
+ if (grp == 0 || (grp == 1 && reg < 6))
+ val -= (reg + 8 * grp);
+ else if (grp == 1 && reg == 6)
+ val = &fp->usp;
+ else if (grp == 1 && reg == 7)
+ val = &fp->fp;
+ else if (grp == 2) {
+ val = &fp->i0;
+ val -= reg;
+ } else if (grp == 3 && reg >= 4) {
+ val = &fp->l0;
+ val -= (reg - 4);
+ } else if (grp == 3 && reg < 4) {
+ val = &fp->b0;
+ val -= reg;
+ } else if (grp == 4 && reg < 4) {
+ val = &fp->a0x;
+ val -= reg;
+ } else if (grp == 4 && reg == 6)
+ val = &fp->astat;
+ else if (grp == 4 && reg == 7)
+ val = &fp->rets;
+ else if (grp == 6 && reg < 6) {
+ val = &fp->lc0;
+ val -= reg;
+ } else if (grp == 6 && reg == 6) {
+ __asm__ __volatile__("%0 = cycles;\n" : "=d"(tmp));
+ val = &tmp;
+ } else if (grp == 6 && reg == 7) {
+ __asm__ __volatile__("%0 = cycles2;\n" : "=d"(tmp));
+ val = &tmp;
+ }
+
+ *value = *val;
+ return true;
+
+}
+
+#define PseudoDbg_Assert_opcode 0xf0000000
+#define PseudoDbg_Assert_expected_bits 0
+#define PseudoDbg_Assert_expected_mask 0xffff
+#define PseudoDbg_Assert_regtest_bits 16
+#define PseudoDbg_Assert_regtest_mask 0x7
+#define PseudoDbg_Assert_grp_bits 19
+#define PseudoDbg_Assert_grp_mask 0x7
+#define PseudoDbg_Assert_dbgop_bits 22
+#define PseudoDbg_Assert_dbgop_mask 0x3
+#define PseudoDbg_Assert_dontcare_bits 24
+#define PseudoDbg_Assert_dontcare_mask 0x7
+#define PseudoDbg_Assert_code_bits 27
+#define PseudoDbg_Assert_code_mask 0x1f
+
+/*
+ * DBGA - debug assert
+ */
+bool execute_pseudodbg_assert(struct pt_regs *fp, unsigned int opcode)
+{
+ int expected = ((opcode >> PseudoDbg_Assert_expected_bits) & PseudoDbg_Assert_expected_mask);
+ int dbgop = ((opcode >> (PseudoDbg_Assert_dbgop_bits)) & PseudoDbg_Assert_dbgop_mask);
+ int grp = ((opcode >> (PseudoDbg_Assert_grp_bits)) & PseudoDbg_Assert_grp_mask);
+ int regtest = ((opcode >> (PseudoDbg_Assert_regtest_bits)) & PseudoDbg_Assert_regtest_mask);
+ long value;
+
+ if ((opcode & 0xFF000000) != PseudoDbg_Assert_opcode)
+ return false;
+
+ if (!fix_up_reg(fp, &value, grp, regtest))
+ return false;
+
+ if (dbgop == 0 || dbgop == 2) {
+ /* DBGA ( regs_lo , uimm16 ) */
+ /* DBGAL ( regs , uimm16 ) */
+ if (expected != (value & 0xFFFF)) {
+ pr_notice("DBGA (%s.L,0x%x) failure, got 0x%x\n",
+ get_allreg_name(grp, regtest),
+ expected, (unsigned int)(value & 0xFFFF));
+ return false;
+ }
+
+ } else if (dbgop == 1 || dbgop == 3) {
+ /* DBGA ( regs_hi , uimm16 ) */
+ /* DBGAH ( regs , uimm16 ) */
+ if (expected != ((value >> 16) & 0xFFFF)) {
+ pr_notice("DBGA (%s.H,0x%x) failure, got 0x%x\n",
+ get_allreg_name(grp, regtest),
+ expected, (unsigned int)((value >> 16) & 0xFFFF));
+ return false;
+ }
+ }
+
+ fp->pc += 4;
+ return true;
+}
+
+#define PseudoDbg_opcode 0xf8000000
+#define PseudoDbg_reg_bits 0
+#define PseudoDbg_reg_mask 0x7
+#define PseudoDbg_grp_bits 3
+#define PseudoDbg_grp_mask 0x7
+#define PseudoDbg_fn_bits 6
+#define PseudoDbg_fn_mask 0x3
+#define PseudoDbg_code_bits 8
+#define PseudoDbg_code_mask 0xff
+
+/*
+ * DBG - debug (dump a register value out)
+ */
+bool execute_pseudodbg(struct pt_regs *fp, unsigned int opcode)
+{
+ int grp, fn, reg;
+ long value, value1;
+
+ if ((opcode & 0xFF000000) != PseudoDbg_opcode)
+ return false;
+
+ opcode >>= 16;
+ grp = ((opcode >> PseudoDbg_grp_bits) & PseudoDbg_reg_mask);
+ fn = ((opcode >> PseudoDbg_fn_bits) & PseudoDbg_fn_mask);
+ reg = ((opcode >> PseudoDbg_reg_bits) & PseudoDbg_reg_mask);
+
+ if (fn == 3 && (reg == 0 || reg == 1)) {
+ if (!fix_up_reg(fp, &value, 4, 2 * reg))
+ return false;
+ if (!fix_up_reg(fp, &value1, 4, 2 * reg + 1))
+ return false;
+
+ pr_notice("DBG A%i = %02lx%08lx\n", reg, value & 0xFF, value1);
+ fp->pc += 2;
+ return true;
+
+ } else if (fn == 0) {
+ if (!fix_up_reg(fp, &value, grp, reg))
+ return false;
+
+ pr_notice("DBG %s = %08lx\n", get_allreg_name(grp, reg), value);
+ fp->pc += 2;
+ return true;
+ }
+
+ return false;
+}