src/target/armv7m_trace.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2
   3 /***************************************************************************
   4  *   Copyright (C) 2015  Paul Fertser <fercerpav@gmail.com>                *
   5  ***************************************************************************/
   6
   7 #ifdef HAVE_CONFIG_H
   8 #include "config.h"
   9 #endif
  10
  11 #include <target/target.h>
  12 #include <target/armv7m.h>
  13 #include <target/cortex_m.h>
  14 #include <target/armv7m_trace.h>
  15 #include <jtag/interface.h>
  16 #include <helper/time_support.h>
  17
  18 int armv7m_trace_itm_config(struct target *target)
  19 {
  20         struct armv7m_common *armv7m = target_to_armv7m(target);
  21         struct armv7m_trace_config *trace_config = &armv7m->trace_config;
  22         int retval;
  23
  24         retval = target_write_u32(target, ITM_LAR, ITM_LAR_KEY);
  25         if (retval != ERROR_OK)
  26                 return retval;
  27
  28         /* pg315 of CoreSight Components
  29          * It is recommended that the ITMEn bit is cleared and waits for the
  30          * ITMBusy bit to be cleared, before changing any fields in the
  31          * Control Register, otherwise the behavior can be unpredictable.
  32          */
  33         uint32_t itm_tcr;
  34         retval = target_read_u32(target, ITM_TCR, &itm_tcr);
  35         if (retval != ERROR_OK)
  36                 return retval;
  37         retval = target_write_u32(target,
  38                         ITM_TCR,
  39                         itm_tcr & ~ITM_TCR_ITMENA_BIT
  40                         );
  41         if (retval != ERROR_OK)
  42                 return retval;
  43
  44         int64_t then = timeval_ms() + 1000;
  45         do {
  46                 retval = target_read_u32(target, ITM_TCR, &itm_tcr);
  47                 if (retval != ERROR_OK)
  48                         return retval;
  49                 if (timeval_ms() > then) {
  50                         LOG_ERROR("timeout waiting for ITM_TCR_BUSY_BIT");
  51                         return ERROR_FAIL;
  52                 }
  53         } while (itm_tcr & ITM_TCR_BUSY_BIT);
  54
  55         /* Enable ITM, TXENA, set TraceBusID and other parameters */
  56         retval = target_write_u32(target, ITM_TCR, (1 << 0) | (1 << 3) |
  57                                   (trace_config->itm_diff_timestamps << 1) |
  58                                   (trace_config->itm_synchro_packets << 2) |
  59                                   (trace_config->itm_async_timestamps << 4) |
  60                                   (trace_config->itm_ts_prescale << 8) |
  61                                   (trace_config->trace_bus_id << 16));
  62         if (retval != ERROR_OK)
  63                 return retval;
  64
  65         for (unsigned int i = 0; i < 8; i++) {
  66                 retval = target_write_u32(target, ITM_TER0 + i * 4,
  67                                           trace_config->itm_ter[i]);
  68                 if (retval != ERROR_OK)
  69                         return retval;
  70         }
  71
  72         return ERROR_OK;
  73 }
  74
  75 COMMAND_HANDLER(handle_itm_port_command)
  76 {
  77         struct target *target = get_current_target(CMD_CTX);
  78         struct armv7m_common *armv7m = target_to_armv7m(target);
  79         unsigned int reg_idx;
  80         uint8_t port;
  81         bool enable;
  82
  83         if (CMD_ARGC != 2)
  84                 return ERROR_COMMAND_SYNTAX_ERROR;
  85
  86         COMMAND_PARSE_NUMBER(u8, CMD_ARGV[0], port);
  87         COMMAND_PARSE_ON_OFF(CMD_ARGV[1], enable);
  88         reg_idx = port / 32;
  89         port = port % 32;
  90         if (enable)
  91                 armv7m->trace_config.itm_ter[reg_idx] |= (1 << port);
  92         else
  93                 armv7m->trace_config.itm_ter[reg_idx] &= ~(1 << port);
  94
  95         if (CMD_CTX->mode == COMMAND_EXEC)
  96                 return armv7m_trace_itm_config(target);
  97
  98         armv7m->trace_config.itm_deferred_config = true;
  99         return ERROR_OK;
 100 }
 101
 102 COMMAND_HANDLER(handle_itm_ports_command)
 103 {
 104         struct target *target = get_current_target(CMD_CTX);
 105         struct armv7m_common *armv7m = target_to_armv7m(target);
 106         bool enable;
 107
 108         if (CMD_ARGC != 1)
 109                 return ERROR_COMMAND_SYNTAX_ERROR;
 110
 111         COMMAND_PARSE_ON_OFF(CMD_ARGV[0], enable);
 112         memset(armv7m->trace_config.itm_ter, enable ? 0xff : 0,
 113                sizeof(armv7m->trace_config.itm_ter));
 114
 115         if (CMD_CTX->mode == COMMAND_EXEC)
 116                 return armv7m_trace_itm_config(target);
 117
 118         armv7m->trace_config.itm_deferred_config = true;
 119         return ERROR_OK;
 120 }
 121
 122 static const struct command_registration itm_command_handlers[] = {
 123         {
 124                 .name = "port",
 125                 .handler = handle_itm_port_command,
 126                 .mode = COMMAND_ANY,
 127                 .help = "Enable or disable ITM stimulus port",
 128                 .usage = "<port> (0|1|on|off)",
 129         },
 130         {
 131                 .name = "ports",
 132                 .handler = handle_itm_ports_command,
 133                 .mode = COMMAND_ANY,
 134                 .help = "Enable or disable all ITM stimulus ports",
 135                 .usage = "(0|1|on|off)",
 136         },
 137         COMMAND_REGISTRATION_DONE
 138 };
 139
 140 const struct command_registration armv7m_trace_command_handlers[] = {
 141         {
 142                 .name = "itm",
 143                 .mode = COMMAND_ANY,
 144                 .help = "itm command group",
 145                 .usage = "",
 146                 .chain = itm_command_handlers,
 147         },
 148         COMMAND_REGISTRATION_DONE
 149 };