drivers/remoteproc/st_remoteproc.c

   1 /*
   2  * ST's Remote Processor Control Driver
   3  *
   4  * Copyright (C) 2015 STMicroelectronics - All Rights Reserved
   5  *
   6  * Author: Ludovic Barre <ludovic.barre@st.com>
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License version 2 as
  10  * published by the Free Software Foundation.
  11  */
  12
  13 #include <linux/clk.h>
  14 #include <linux/dma-mapping.h>
  15 #include <linux/err.h>
  16 #include <linux/interrupt.h>
  17 #include <linux/kernel.h>
  18 #include <linux/mailbox_client.h>
  19 #include <linux/mfd/syscon.h>
  20 #include <linux/module.h>
  21 #include <linux/of.h>
  22 #include <linux/of_device.h>
  23 #include <linux/of_reserved_mem.h>
  24 #include <linux/platform_device.h>
  25 #include <linux/regmap.h>
  26 #include <linux/remoteproc.h>
  27 #include <linux/reset.h>
  28
  29 #include "remoteproc_internal.h"
  30
  31 #define ST_RPROC_VQ0            0
  32 #define ST_RPROC_VQ1            1
  33 #define ST_RPROC_MAX_VRING      2
  34
  35 #define MBOX_RX                 0
  36 #define MBOX_TX                 1
  37 #define MBOX_MAX                2
  38
  39 struct st_rproc_config {
  40         bool                    sw_reset;
  41         bool                    pwr_reset;
  42         unsigned long           bootaddr_mask;
  43 };
  44
  45 struct st_rproc {
  46         struct st_rproc_config  *config;
  47         struct reset_control    *sw_reset;
  48         struct reset_control    *pwr_reset;
  49         struct clk              *clk;
  50         u32                     clk_rate;
  51         struct regmap           *boot_base;
  52         u32                     boot_offset;
  53         struct mbox_chan        *mbox_chan[ST_RPROC_MAX_VRING * MBOX_MAX];
  54         struct mbox_client mbox_client_vq0;
  55         struct mbox_client mbox_client_vq1;
  56 };
  57
  58 static void st_rproc_mbox_callback(struct device *dev, u32 msg)
  59 {
  60         struct rproc *rproc = dev_get_drvdata(dev);
  61
  62         if (rproc_vq_interrupt(rproc, msg) == IRQ_NONE)
  63                 dev_dbg(dev, "no message was found in vqid %d\n", msg);
  64 }
  65
  66 static
  67 void st_rproc_mbox_callback_vq0(struct mbox_client *mbox_client, void *data)
  68 {
  69         st_rproc_mbox_callback(mbox_client->dev, 0);
  70 }
  71
  72 static
  73 void st_rproc_mbox_callback_vq1(struct mbox_client *mbox_client, void *data)
  74 {
  75         st_rproc_mbox_callback(mbox_client->dev, 1);
  76 }
  77
  78 static void st_rproc_kick(struct rproc *rproc, int vqid)
  79 {
  80         struct st_rproc *ddata = rproc->priv;
  81         struct device *dev = rproc->dev.parent;
  82         int ret;
  83
  84         /* send the index of the triggered virtqueue in the mailbox payload */
  85         if (WARN_ON(vqid >= ST_RPROC_MAX_VRING))
  86                 return;
  87
  88         ret = mbox_send_message(ddata->mbox_chan[vqid * MBOX_MAX + MBOX_TX],
  89                                 (void *)&vqid);
  90         if (ret < 0)
  91                 dev_err(dev, "failed to send message via mbox: %d\n", ret);
  92 }
  93
  94 static int st_rproc_start(struct rproc *rproc)
  95 {
  96         struct st_rproc *ddata = rproc->priv;
  97         int err;
  98
  99         regmap_update_bits(ddata->boot_base, ddata->boot_offset,
 100                            ddata->config->bootaddr_mask, rproc->bootaddr);
 101
 102         err = clk_enable(ddata->clk);
 103         if (err) {
 104                 dev_err(&rproc->dev, "Failed to enable clock\n");
 105                 return err;
 106         }
 107
 108         if (ddata->config->sw_reset) {
 109                 err = reset_control_deassert(ddata->sw_reset);
 110                 if (err) {
 111                         dev_err(&rproc->dev, "Failed to deassert S/W Reset\n");
 112                         goto sw_reset_fail;
 113                 }
 114         }
 115
 116         if (ddata->config->pwr_reset) {
 117                 err = reset_control_deassert(ddata->pwr_reset);
 118                 if (err) {
 119                         dev_err(&rproc->dev, "Failed to deassert Power Reset\n");
 120                         goto pwr_reset_fail;
 121                 }
 122         }
 123
 124         dev_info(&rproc->dev, "Started from 0x%x\n", rproc->bootaddr);
 125
 126         return 0;
 127
 128
 129 pwr_reset_fail:
 130         if (ddata->config->pwr_reset)
 131                 reset_control_assert(ddata->sw_reset);
 132 sw_reset_fail:
 133         clk_disable(ddata->clk);
 134
 135         return err;
 136 }
 137
 138 static int st_rproc_stop(struct rproc *rproc)
 139 {
 140         struct st_rproc *ddata = rproc->priv;
 141         int sw_err = 0, pwr_err = 0;
 142
 143         if (ddata->config->sw_reset) {
 144                 sw_err = reset_control_assert(ddata->sw_reset);
 145                 if (sw_err)
 146                         dev_err(&rproc->dev, "Failed to assert S/W Reset\n");
 147         }
 148
 149         if (ddata->config->pwr_reset) {
 150                 pwr_err = reset_control_assert(ddata->pwr_reset);
 151                 if (pwr_err)
 152                         dev_err(&rproc->dev, "Failed to assert Power Reset\n");
 153         }
 154
 155         clk_disable(ddata->clk);
 156
 157         return sw_err ?: pwr_err;
 158 }
 159
 160 static const struct rproc_ops st_rproc_ops = {
 161         .kick           = st_rproc_kick,
 162         .start          = st_rproc_start,
 163         .stop           = st_rproc_stop,
 164 };
 165
 166 /*
 167  * Fetch state of the processor: 0 is off, 1 is on.
 168  */
 169 static int st_rproc_state(struct platform_device *pdev)
 170 {
 171         struct rproc *rproc = platform_get_drvdata(pdev);
 172         struct st_rproc *ddata = rproc->priv;
 173         int reset_sw = 0, reset_pwr = 0;
 174
 175         if (ddata->config->sw_reset)
 176                 reset_sw = reset_control_status(ddata->sw_reset);
 177
 178         if (ddata->config->pwr_reset)
 179                 reset_pwr = reset_control_status(ddata->pwr_reset);
 180
 181         if (reset_sw < 0 || reset_pwr < 0)
 182                 return -EINVAL;
 183
 184         return !reset_sw && !reset_pwr;
 185 }
 186
 187 static const struct st_rproc_config st40_rproc_cfg = {
 188         .sw_reset = true,
 189         .pwr_reset = true,
 190         .bootaddr_mask = GENMASK(28, 1),
 191 };
 192
 193 static const struct st_rproc_config st231_rproc_cfg = {
 194         .sw_reset = true,
 195         .pwr_reset = false,
 196         .bootaddr_mask = GENMASK(31, 6),
 197 };
 198
 199 static const struct of_device_id st_rproc_match[] = {
 200         { .compatible = "st,st40-rproc", .data = &st40_rproc_cfg },
 201         { .compatible = "st,st231-rproc", .data = &st231_rproc_cfg },
 202         {},
 203 };
 204 MODULE_DEVICE_TABLE(of, st_rproc_match);
 205
 206 static int st_rproc_parse_dt(struct platform_device *pdev)
 207 {
 208         struct device *dev = &pdev->dev;
 209         struct rproc *rproc = platform_get_drvdata(pdev);
 210         struct st_rproc *ddata = rproc->priv;
 211         struct device_node *np = dev->of_node;
 212         int err;
 213
 214         if (ddata->config->sw_reset) {
 215                 ddata->sw_reset = devm_reset_control_get(dev, "sw_reset");
 216                 if (IS_ERR(ddata->sw_reset)) {
 217                         dev_err(dev, "Failed to get S/W Reset\n");
 218                         return PTR_ERR(ddata->sw_reset);
 219                 }
 220         }
 221
 222         if (ddata->config->pwr_reset) {
 223                 ddata->pwr_reset = devm_reset_control_get(dev, "pwr_reset");
 224                 if (IS_ERR(ddata->pwr_reset)) {
 225                         dev_err(dev, "Failed to get Power Reset\n");
 226                         return PTR_ERR(ddata->pwr_reset);
 227                 }
 228         }
 229
 230         ddata->clk = devm_clk_get(dev, NULL);
 231         if (IS_ERR(ddata->clk)) {
 232                 dev_err(dev, "Failed to get clock\n");
 233                 return PTR_ERR(ddata->clk);
 234         }
 235
 236         err = of_property_read_u32(np, "clock-frequency", &ddata->clk_rate);
 237         if (err) {
 238                 dev_err(dev, "failed to get clock frequency\n");
 239                 return err;
 240         }
 241
 242         ddata->boot_base = syscon_regmap_lookup_by_phandle(np, "st,syscfg");
 243         if (IS_ERR(ddata->boot_base)) {
 244                 dev_err(dev, "Boot base not found\n");
 245                 return PTR_ERR(ddata->boot_base);
 246         }
 247
 248         err = of_property_read_u32_index(np, "st,syscfg", 1,
 249                                          &ddata->boot_offset);
 250         if (err) {
 251                 dev_err(dev, "Boot offset not found\n");
 252                 return -EINVAL;
 253         }
 254
 255         err = of_reserved_mem_device_init(dev);
 256         if (err) {
 257                 dev_err(dev, "Failed to obtain shared memory\n");
 258                 return err;
 259         }
 260
 261         err = clk_prepare(ddata->clk);
 262         if (err)
 263                 dev_err(dev, "failed to get clock\n");
 264
 265         return err;
 266 }
 267
 268 static int st_rproc_probe(struct platform_device *pdev)
 269 {
 270         struct device *dev = &pdev->dev;
 271         const struct of_device_id *match;
 272         struct st_rproc *ddata;
 273         struct device_node *np = dev->of_node;
 274         struct rproc *rproc;
 275         struct mbox_chan *chan;
 276         int enabled;
 277         int ret, i;
 278
 279         match = of_match_device(st_rproc_match, dev);
 280         if (!match || !match->data) {
 281                 dev_err(dev, "No device match found\n");
 282                 return -ENODEV;
 283         }
 284
 285         rproc = rproc_alloc(dev, np->name, &st_rproc_ops, NULL, sizeof(*ddata));
 286         if (!rproc)
 287                 return -ENOMEM;
 288
 289         rproc->has_iommu = false;
 290         ddata = rproc->priv;
 291         ddata->config = (struct st_rproc_config *)match->data;
 292
 293         platform_set_drvdata(pdev, rproc);
 294
 295         ret = st_rproc_parse_dt(pdev);
 296         if (ret)
 297                 goto free_rproc;
 298
 299         enabled = st_rproc_state(pdev);
 300         if (enabled < 0) {
 301                 ret = enabled;
 302                 goto free_clk;
 303         }
 304
 305         if (enabled) {
 306                 atomic_inc(&rproc->power);
 307                 rproc->state = RPROC_RUNNING;
 308         } else {
 309                 clk_set_rate(ddata->clk, ddata->clk_rate);
 310         }
 311
 312         if (of_get_property(np, "mbox-names", NULL)) {
 313                 ddata->mbox_client_vq0.dev              = dev;
 314                 ddata->mbox_client_vq0.tx_done          = NULL;
 315                 ddata->mbox_client_vq0.tx_block = false;
 316                 ddata->mbox_client_vq0.knows_txdone     = false;
 317                 ddata->mbox_client_vq0.rx_callback      = st_rproc_mbox_callback_vq0;
 318
 319                 ddata->mbox_client_vq1.dev              = dev;
 320                 ddata->mbox_client_vq1.tx_done          = NULL;
 321                 ddata->mbox_client_vq1.tx_block = false;
 322                 ddata->mbox_client_vq1.knows_txdone     = false;
 323                 ddata->mbox_client_vq1.rx_callback      = st_rproc_mbox_callback_vq1;
 324
 325                 /*
 326                  * To control a co-processor without IPC mechanism.
 327                  * This driver can be used without mbox and rpmsg.
 328                  */
 329                 chan = mbox_request_channel_byname(&ddata->mbox_client_vq0, "vq0_rx");
 330                 if (IS_ERR(chan)) {
 331                         dev_err(&rproc->dev, "failed to request mbox chan 0\n");
 332                         ret = PTR_ERR(chan);
 333                         goto free_clk;
 334                 }
 335                 ddata->mbox_chan[ST_RPROC_VQ0 * MBOX_MAX + MBOX_RX] = chan;
 336
 337                 chan = mbox_request_channel_byname(&ddata->mbox_client_vq0, "vq0_tx");
 338                 if (IS_ERR(chan)) {
 339                         dev_err(&rproc->dev, "failed to request mbox chan 0\n");
 340                         ret = PTR_ERR(chan);
 341                         goto free_mbox;
 342                 }
 343                 ddata->mbox_chan[ST_RPROC_VQ0 * MBOX_MAX + MBOX_TX] = chan;
 344
 345                 chan = mbox_request_channel_byname(&ddata->mbox_client_vq1, "vq1_rx");
 346                 if (IS_ERR(chan)) {
 347                         dev_err(&rproc->dev, "failed to request mbox chan 1\n");
 348                         ret = PTR_ERR(chan);
 349                         goto free_mbox;
 350                 }
 351                 ddata->mbox_chan[ST_RPROC_VQ1 * MBOX_MAX + MBOX_RX] = chan;
 352
 353                 chan = mbox_request_channel_byname(&ddata->mbox_client_vq1, "vq1_tx");
 354                 if (IS_ERR(chan)) {
 355                         dev_err(&rproc->dev, "failed to request mbox chan 1\n");
 356                         ret = PTR_ERR(chan);
 357                         goto free_mbox;
 358                 }
 359                 ddata->mbox_chan[ST_RPROC_VQ1 * MBOX_MAX + MBOX_TX] = chan;
 360         }
 361
 362         ret = rproc_add(rproc);
 363         if (ret)
 364                 goto free_mbox;
 365
 366         return 0;
 367
 368 free_mbox:
 369         for (i = 0; i < ST_RPROC_MAX_VRING * MBOX_MAX; i++)
 370                 mbox_free_channel(ddata->mbox_chan[i]);
 371 free_clk:
 372         clk_unprepare(ddata->clk);
 373 free_rproc:
 374         rproc_free(rproc);
 375         return ret;
 376 }
 377
 378 static int st_rproc_remove(struct platform_device *pdev)
 379 {
 380         struct rproc *rproc = platform_get_drvdata(pdev);
 381         struct st_rproc *ddata = rproc->priv;
 382         int i;
 383
 384         rproc_del(rproc);
 385
 386         clk_disable_unprepare(ddata->clk);
 387
 388         of_reserved_mem_device_release(&pdev->dev);
 389
 390         for (i = 0; i < ST_RPROC_MAX_VRING * MBOX_MAX; i++)
 391                 mbox_free_channel(ddata->mbox_chan[i]);
 392
 393         rproc_free(rproc);
 394
 395         return 0;
 396 }
 397
 398 static struct platform_driver st_rproc_driver = {
 399         .probe = st_rproc_probe,
 400         .remove = st_rproc_remove,
 401         .driver = {
 402                 .name = "st-rproc",
 403                 .of_match_table = of_match_ptr(st_rproc_match),
 404         },
 405 };
 406 module_platform_driver(st_rproc_driver);
 407
 408 MODULE_DESCRIPTION("ST Remote Processor Control Driver");
 409 MODULE_AUTHOR("Ludovic Barre <ludovic.barre@st.com>");
 410 MODULE_LICENSE("GPL v2");