diff options
Diffstat (limited to 'arch/blackfin/kernel/pseudodbg.c')
-rw-r--r-- | arch/blackfin/kernel/pseudodbg.c | 191 |
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 @@ -0,0 +1,191 @@ +/* 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; +} |