src/rtt/rtt.c

   1 /* SPDX-License-Identifier: GPL-2.0-or-later */
   2
   3 /*
   4  * Copyright (C) 2016-2020 by Marc Schink <dev@zapb.de>
   5  */
   6
   7 #ifdef HAVE_CONFIG_H
   8 #include "config.h"
   9 #endif
  10
  11 #include <stdint.h>
  12 #include <stdbool.h>
  13 #include <string.h>
  14
  15 #include <helper/log.h>
  16 #include <helper/list.h>
  17 #include <target/target.h>
  18 #include <target/rtt.h>
  19
  20 #include "rtt.h"
  21
  22 static struct {
  23         struct rtt_source source;
  24         /** Control block. */
  25         struct rtt_control ctrl;
  26         struct target *target;
  27         /** Start address to search for the control block. */
  28         target_addr_t addr;
  29         /** Size of the control block search area. */
  30         size_t size;
  31         /** Control block identifier. */
  32         char id[RTT_CB_MAX_ID_LENGTH];
  33         /** Whether RTT is configured. */
  34         bool configured;
  35         /** Whether RTT is started. */
  36         bool started;
  37         /** Whether configuration changed. */
  38         bool changed;
  39         /** Whether the control block was found. */
  40         bool found_cb;
  41
  42         struct rtt_sink_list **sink_list;
  43         size_t sink_list_length;
  44
  45         unsigned int polling_interval;
  46 } rtt;
  47
  48 int rtt_init(void)
  49 {
  50         rtt.sink_list_length = 1;
  51         rtt.sink_list = calloc(rtt.sink_list_length,
  52                 sizeof(struct rtt_sink_list *));
  53
  54         if (!rtt.sink_list)
  55                 return ERROR_FAIL;
  56
  57         rtt.sink_list[0] = NULL;
  58         rtt.started = false;
  59
  60         rtt.polling_interval = 100;
  61
  62         return ERROR_OK;
  63 }
  64
  65 int rtt_exit(void)
  66 {
  67         free(rtt.sink_list);
  68
  69         return ERROR_OK;
  70 }
  71
  72 static int read_channel_callback(void *user_data)
  73 {
  74         int ret;
  75
  76         ret = rtt.source.read(rtt.target, &rtt.ctrl, rtt.sink_list,
  77                 rtt.sink_list_length, NULL);
  78
  79         if (ret != ERROR_OK) {
  80                 target_unregister_timer_callback(&read_channel_callback, NULL);
  81                 rtt.source.stop(rtt.target, NULL);
  82                 return ret;
  83         }
  84
  85         return ERROR_OK;
  86 }
  87
  88 int rtt_setup(target_addr_t address, size_t size, const char *id)
  89 {
  90         size_t id_length = strlen(id);
  91
  92         if (!id_length || id_length >= RTT_CB_MAX_ID_LENGTH) {
  93                 LOG_ERROR("rtt: Invalid control block ID");
  94                 return ERROR_COMMAND_ARGUMENT_INVALID;
  95         }
  96
  97         rtt.addr = address;
  98         rtt.size = size;
  99         strncpy(rtt.id, id, id_length + 1);
 100         rtt.changed = true;
 101         rtt.configured = true;
 102
 103         return ERROR_OK;
 104 }
 105
 106 int rtt_register_source(const struct rtt_source source,
 107                 struct target *target)
 108 {
 109         if (!source.find_cb || !source.read_cb || !source.read_channel_info)
 110                 return ERROR_FAIL;
 111
 112         if (!source.start || !source.stop)
 113                 return ERROR_FAIL;
 114
 115         if (!source.read || !source.write)
 116                 return ERROR_FAIL;
 117
 118         rtt.source = source;
 119         rtt.target = target;
 120
 121         return ERROR_OK;
 122 }
 123
 124 int rtt_start(void)
 125 {
 126         int ret;
 127         target_addr_t addr = rtt.addr;
 128
 129         if (rtt.started)
 130                 return ERROR_OK;
 131
 132         if (!rtt.found_cb || rtt.changed) {
 133                 rtt.source.find_cb(rtt.target, &addr, rtt.size, rtt.id,
 134                         &rtt.found_cb, NULL);
 135
 136                 rtt.changed = false;
 137
 138                 if (rtt.found_cb) {
 139                         LOG_INFO("rtt: Control block found at 0x%" TARGET_PRIxADDR,
 140                                 addr);
 141                         rtt.ctrl.address = addr;
 142                 } else {
 143                         LOG_INFO("rtt: No control block found");
 144                         return ERROR_OK;
 145                 }
 146         }
 147
 148         ret = rtt.source.read_cb(rtt.target, rtt.ctrl.address, &rtt.ctrl, NULL);
 149
 150         if (ret != ERROR_OK)
 151                 return ret;
 152
 153         ret = rtt.source.start(rtt.target, &rtt.ctrl, NULL);
 154
 155         if (ret != ERROR_OK)
 156                 return ret;
 157
 158         target_register_timer_callback(&read_channel_callback,
 159                 rtt.polling_interval, 1, NULL);
 160         rtt.started = true;
 161
 162         return ERROR_OK;
 163 }
 164
 165 int rtt_stop(void)
 166 {
 167         int ret;
 168
 169         if (!rtt.configured) {
 170                 LOG_ERROR("rtt: Not configured");
 171                 return ERROR_FAIL;
 172         }
 173
 174         target_unregister_timer_callback(&read_channel_callback, NULL);
 175         rtt.started = false;
 176
 177         ret = rtt.source.stop(rtt.target, NULL);
 178
 179         if (ret != ERROR_OK)
 180                 return ret;
 181
 182         return ERROR_OK;
 183 }
 184
 185 static int adjust_sink_list(size_t length)
 186 {
 187         struct rtt_sink_list **tmp;
 188
 189         if (length <= rtt.sink_list_length)
 190                 return ERROR_OK;
 191
 192         tmp = realloc(rtt.sink_list, sizeof(struct rtt_sink_list *) * length);
 193
 194         if (!tmp)
 195                 return ERROR_FAIL;
 196
 197         for (size_t i = rtt.sink_list_length; i < length; i++)
 198                 tmp[i] = NULL;
 199
 200         rtt.sink_list = tmp;
 201         rtt.sink_list_length = length;
 202
 203         return ERROR_OK;
 204 }
 205
 206 int rtt_register_sink(unsigned int channel_index, rtt_sink_read read,
 207                 void *user_data)
 208 {
 209         struct rtt_sink_list *tmp;
 210
 211         if (channel_index >= rtt.sink_list_length) {
 212                 if (adjust_sink_list(channel_index + 1) != ERROR_OK)
 213                         return ERROR_FAIL;
 214         }
 215
 216         LOG_DEBUG("rtt: Registering sink for channel %u", channel_index);
 217
 218         tmp = malloc(sizeof(struct rtt_sink_list));
 219
 220         if (!tmp)
 221                 return ERROR_FAIL;
 222
 223         tmp->read = read;
 224         tmp->user_data = user_data;
 225         tmp->next = rtt.sink_list[channel_index];
 226
 227         rtt.sink_list[channel_index] = tmp;
 228
 229         return ERROR_OK;
 230 }
 231
 232 int rtt_unregister_sink(unsigned int channel_index, rtt_sink_read read,
 233                 void *user_data)
 234 {
 235         struct rtt_sink_list *prev_sink;
 236
 237         LOG_DEBUG("rtt: Unregistering sink for channel %u", channel_index);
 238
 239         if (channel_index >= rtt.sink_list_length)
 240                 return ERROR_FAIL;
 241
 242         prev_sink = rtt.sink_list[channel_index];
 243
 244         for (struct rtt_sink_list *sink = rtt.sink_list[channel_index]; sink;
 245                         prev_sink = sink, sink = sink->next) {
 246                 if (sink->read == read && sink->user_data == user_data) {
 247
 248                         if (sink == rtt.sink_list[channel_index])
 249                                 rtt.sink_list[channel_index] = sink->next;
 250                         else
 251                                 prev_sink->next = sink->next;
 252
 253                         free(sink);
 254
 255                         return ERROR_OK;
 256                 }
 257         }
 258
 259         return ERROR_OK;
 260 }
 261
 262 int rtt_get_polling_interval(unsigned int *interval)
 263 {
 264         if (!interval)
 265                 return ERROR_FAIL;
 266
 267         *interval = rtt.polling_interval;
 268
 269         return ERROR_OK;
 270 }
 271
 272 int rtt_set_polling_interval(unsigned int interval)
 273 {
 274         if (!interval)
 275                 return ERROR_FAIL;
 276
 277         if (rtt.polling_interval != interval) {
 278                 target_unregister_timer_callback(&read_channel_callback, NULL);
 279                 target_register_timer_callback(&read_channel_callback, interval, 1,
 280                         NULL);
 281         }
 282
 283         rtt.polling_interval = interval;
 284
 285         return ERROR_OK;
 286 }
 287
 288 int rtt_write_channel(unsigned int channel_index, const uint8_t *buffer,
 289                 size_t *length)
 290 {
 291         if (channel_index >= rtt.ctrl.num_up_channels) {
 292                 LOG_WARNING("rtt: Down-channel %u is not available", channel_index);
 293                 return ERROR_OK;
 294         }
 295
 296         return rtt.source.write(rtt.target, &rtt.ctrl, channel_index, buffer,
 297                 length, NULL);
 298 }
 299
 300 bool rtt_started(void)
 301 {
 302         return rtt.started;
 303 }
 304
 305 bool rtt_configured(void)
 306 {
 307         return rtt.configured;
 308 }
 309
 310 bool rtt_found_cb(void)
 311 {
 312         return rtt.found_cb;
 313 }
 314
 315 const struct rtt_control *rtt_get_control(void)
 316 {
 317         return &rtt.ctrl;
 318 }
 319
 320 int rtt_read_channel_info(unsigned int channel_index,
 321         enum rtt_channel_type type, struct rtt_channel_info *info)
 322 {
 323         return rtt.source.read_channel_info(rtt.target, &rtt.ctrl,
 324                 channel_index, type, info, NULL);
 325 }