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-rw-r--r--arch/blackfin/kernel/pseudodbg.c73
1 files changed, 73 insertions, 0 deletions
diff --git a/arch/blackfin/kernel/pseudodbg.c b/arch/blackfin/kernel/pseudodbg.c
new file mode 100644
index 00000000000..4474b8db350
--- /dev/null
+++ b/arch/blackfin/kernel/pseudodbg.c
@@ -0,0 +1,73 @@
+/* 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>
+
+#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
+
+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 = &fp->r0;
+
+ if ((opcode & 0xFF000000) != PseudoDbg_Assert_opcode)
+ return false;
+
+ /* Only do Dregs and Pregs for now */
+ if (grp > 1)
+ return false;
+
+ /*
+ * 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.
+ */
+ if (grp == 0 || (grp == 1 && regtest < 6))
+ value -= (regtest + 8 * grp);
+ else if (grp == 1 && regtest == 6)
+ value = &fp->usp;
+ else if (grp == 1 && regtest == 7)
+ value = &fp->fp;
+
+ if (dbgop == 0 || dbgop == 2) {
+ /* DBGA ( regs_lo , uimm16 ) */
+ /* DBGAL ( regs , uimm16 ) */
+ if (expected != (*value & 0xFFFF)) {
+ pr_notice("DBGA (%s%i.L,0x%x) failure, got 0x%x\n", grp ? "P" : "R",
+ 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%i.H,0x%x) failure, got 0x%x\n", grp ? "P" : "R",
+ regtest, expected, (unsigned int)((*value >> 16) & 0xFFFF));
+ return false;
+ }
+ }
+
+ fp->pc += 4;
+ return true;
+}