src/target/arm_dpm.h

   1 /*
   2  * Copyright (C) 2009 by David Brownell
   3  *
   4  * This program is free software; you can redistribute it and/or modify
   5  * it under the terms of the GNU General Public License as published by
   6  * the Free Software Foundation; either version 2 of the License, or
   7  * (at your option) any later version.
   8  *
   9  * This program is distributed in the hope that it will be useful
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU General Public License
  15  * along with this program; if not, write to the
  16  * Free Software Foundation, Inc.,
  17  * 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
  18  */
  19
  20 #ifndef __ARM_DPM_H
  21 #define __ARM_DPM_H
  22
  23 /**
  24  * @file
  25  * This is the interface to the Debug Programmers Model for ARMv6 and
  26  * ARMv7 processors.  ARMv6 processors (such as ARM11xx implementations)
  27  * introduced a model which became part of the ARMv7-AR architecture
  28  * which is most familiar through the Cortex-A series parts.  While
  29  * specific details differ (like how to write the instruction register),
  30  * the high level models easily support shared code because those
  31  * registers are compatible.
  32  */
  33
  34 struct dpm_bpwp {
  35         unsigned number;
  36         uint32_t address;
  37         uint32_t control;
  38         /* true if hardware state needs flushing */
  39         bool dirty;
  40 };
  41
  42 struct dpm_bp {
  43         struct breakpoint *bp;
  44         struct dpm_bpwp bpwp;
  45 };
  46
  47 struct dpm_wp {
  48         struct watchpoint *wp;
  49         struct dpm_bpwp bpwp;
  50 };
  51
  52 /**
  53  * This wraps an implementation of DPM primitives.  Each interface
  54  * provider supplies a structure like this, which is the glue between
  55  * upper level code and the lower level hardware access.
  56  *
  57  * It is a PRELIMINARY AND INCOMPLETE set of primitives, starting with
  58  * support for CPU register access.
  59  */
  60 struct arm_dpm {
  61         struct arm *arm;
  62
  63         /** Cache of DIDR */
  64         uint32_t didr;
  65
  66         /** Invoke before a series of instruction operations */
  67         int (*prepare)(struct arm_dpm *);
  68
  69         /** Invoke after a series of instruction operations */
  70         int (*finish)(struct arm_dpm *);
  71
  72         /* WRITE TO CPU */
  73
  74         /** Runs one instruction, writing data to DCC before execution. */
  75         int (*instr_write_data_dcc)(struct arm_dpm *,
  76                         uint32_t opcode, uint32_t data);
  77
  78         /** Runs one instruction, writing data to R0 before execution. */
  79         int (*instr_write_data_r0)(struct arm_dpm *,
  80                         uint32_t opcode, uint32_t data);
  81
  82         /** Optional core-specific operation invoked after CPSR writes. */
  83         int (*instr_cpsr_sync)(struct arm_dpm *dpm);
  84
  85         /* READ FROM CPU */
  86
  87         /** Runs one instruction, reading data from dcc after execution. */
  88         int (*instr_read_data_dcc)(struct arm_dpm *,
  89                         uint32_t opcode, uint32_t *data);
  90
  91         /** Runs one instruction, reading data from r0 after execution. */
  92         int (*instr_read_data_r0)(struct arm_dpm *,
  93                         uint32_t opcode, uint32_t *data);
  94
  95         /* BREAKPOINT/WATCHPOINT SUPPORT */
  96
  97         /**
  98          * Enables one breakpoint or watchpoint by writing to the
  99          * hardware registers.  The specified breakpoint/watchpoint
 100          * must currently be disabled.  Indices 0..15 are used for
 101          * breakpoints; indices 16..31 are for watchpoints.
 102          */
 103         int (*bpwp_enable)(struct arm_dpm *, unsigned index_value,
 104                         uint32_t addr, uint32_t control);
 105
 106         /**
 107          * Disables one breakpoint or watchpoint by clearing its
 108          * hardware control registers.  Indices are the same ones
 109          * accepted by bpwp_enable().
 110          */
 111         int (*bpwp_disable)(struct arm_dpm *, unsigned index_value);
 112
 113         /* The breakpoint and watchpoint arrays are private to the
 114          * DPM infrastructure.  There are nbp indices in the dbp
 115          * array.  There are nwp indices in the dwp array.
 116          */
 117
 118         unsigned nbp;
 119         unsigned nwp;
 120         struct dpm_bp *dbp;
 121         struct dpm_wp *dwp;
 122
 123         /** Address of the instruction which triggered a watchpoint. */
 124         uint32_t wp_pc;
 125
 126         /** Recent value of DSCR. */
 127         uint32_t dscr;
 128
 129         // FIXME -- read/write DCSR methods and symbols
 130 };
 131
 132 int arm_dpm_setup(struct arm_dpm *dpm);
 133 int arm_dpm_initialize(struct arm_dpm *dpm);
 134
 135 int arm_dpm_read_current_registers(struct arm_dpm *);
 136 int arm_dpm_write_dirty_registers(struct arm_dpm *, bool bpwp);
 137
 138 void arm_dpm_report_wfar(struct arm_dpm *, uint32_t wfar);
 139
 140 /* Subset of DSCR bits; see ARMv7a arch spec section C10.3.1.
 141  * Not all v7 bits are valid in v6.
 142  */
 143 #define DSCR_CORE_HALTED        (1 << 0)
 144 #define DSCR_CORE_RESTARTED     (1 << 1)
 145 #define DSCR_INT_DIS            (1 << 11)
 146 #define DSCR_ITR_EN                     (1 << 13)
 147 #define DSCR_HALT_DBG_MODE      (1 << 14)
 148 #define DSCR_MON_DBG_MODE       (1 << 15)
 149 #define DSCR_INSTR_COMP         (1 << 24)
 150 #define DSCR_DTR_TX_FULL        (1 << 29)
 151 #define DSCR_DTR_RX_FULL        (1 << 30)
 152
 153 #define DSCR_ENTRY(dscr)        (((dscr) >> 2) & 0xf)
 154 #define DSCR_RUN_MODE(dscr)     ((dscr) & (DSCR_CORE_HALTED | DSCR_CORE_RESTARTED))
 155
 156 /* DRCR (debug run control register) bits */
 157 #define DRCR_HALT                               (1 << 0)
 158 #define DRCR_RESTART                    (1 << 1)
 159 #define DRCR_CLEAR_EXCEPTIONS   (1 << 2)
 160
 161 void arm_dpm_report_dscr(struct arm_dpm *dpm, uint32_t dcsr);
 162
 163 #endif /* __ARM_DPM_H */