drivers/firmware/qcom_scm.c

   1 /* Copyright (c) 2010,2015, The Linux Foundation. All rights reserved.
   2  * Copyright (C) 2015 Linaro Ltd.
   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 version 2 and
   6  * only version 2 as published by the Free Software Foundation.
   7  *
   8  * This program is distributed in the hope that it will be useful,
   9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  11  * GNU General Public License for more details.
  12  *
  13  */
  14 #include <linux/platform_device.h>
  15 #include <linux/module.h>
  16 #include <linux/cpumask.h>
  17 #include <linux/export.h>
  18 #include <linux/dma-mapping.h>
  19 #include <linux/types.h>
  20 #include <linux/qcom_scm.h>
  21 #include <linux/of.h>
  22 #include <linux/of_platform.h>
  23 #include <linux/clk.h>
  24 #include <linux/reset-controller.h>
  25
  26 #include "qcom_scm.h"
  27
  28 struct qcom_scm {
  29         struct device *dev;
  30         struct clk *core_clk;
  31         struct clk *iface_clk;
  32         struct clk *bus_clk;
  33         struct reset_controller_dev reset;
  34 };
  35
  36 static struct qcom_scm *__scm;
  37
  38 static int qcom_scm_clk_enable(void)
  39 {
  40         int ret;
  41
  42         ret = clk_prepare_enable(__scm->core_clk);
  43         if (ret)
  44                 goto bail;
  45
  46         ret = clk_prepare_enable(__scm->iface_clk);
  47         if (ret)
  48                 goto disable_core;
  49
  50         ret = clk_prepare_enable(__scm->bus_clk);
  51         if (ret)
  52                 goto disable_iface;
  53
  54         return 0;
  55
  56 disable_iface:
  57         clk_disable_unprepare(__scm->iface_clk);
  58 disable_core:
  59         clk_disable_unprepare(__scm->core_clk);
  60 bail:
  61         return ret;
  62 }
  63
  64 static void qcom_scm_clk_disable(void)
  65 {
  66         clk_disable_unprepare(__scm->core_clk);
  67         clk_disable_unprepare(__scm->iface_clk);
  68         clk_disable_unprepare(__scm->bus_clk);
  69 }
  70
  71 /**
  72  * qcom_scm_set_cold_boot_addr() - Set the cold boot address for cpus
  73  * @entry: Entry point function for the cpus
  74  * @cpus: The cpumask of cpus that will use the entry point
  75  *
  76  * Set the cold boot address of the cpus. Any cpu outside the supported
  77  * range would be removed from the cpu present mask.
  78  */
  79 int qcom_scm_set_cold_boot_addr(void *entry, const cpumask_t *cpus)
  80 {
  81         return __qcom_scm_set_cold_boot_addr(entry, cpus);
  82 }
  83 EXPORT_SYMBOL(qcom_scm_set_cold_boot_addr);
  84
  85 /**
  86  * qcom_scm_set_warm_boot_addr() - Set the warm boot address for cpus
  87  * @entry: Entry point function for the cpus
  88  * @cpus: The cpumask of cpus that will use the entry point
  89  *
  90  * Set the Linux entry point for the SCM to transfer control to when coming
  91  * out of a power down. CPU power down may be executed on cpuidle or hotplug.
  92  */
  93 int qcom_scm_set_warm_boot_addr(void *entry, const cpumask_t *cpus)
  94 {
  95         return __qcom_scm_set_warm_boot_addr(__scm->dev, entry, cpus);
  96 }
  97 EXPORT_SYMBOL(qcom_scm_set_warm_boot_addr);
  98
  99 /**
 100  * qcom_scm_cpu_power_down() - Power down the cpu
 101  * @flags - Flags to flush cache
 102  *
 103  * This is an end point to power down cpu. If there was a pending interrupt,
 104  * the control would return from this function, otherwise, the cpu jumps to the
 105  * warm boot entry point set for this cpu upon reset.
 106  */
 107 void qcom_scm_cpu_power_down(u32 flags)
 108 {
 109         __qcom_scm_cpu_power_down(flags);
 110 }
 111 EXPORT_SYMBOL(qcom_scm_cpu_power_down);
 112
 113 /**
 114  * qcom_scm_hdcp_available() - Check if secure environment supports HDCP.
 115  *
 116  * Return true if HDCP is supported, false if not.
 117  */
 118 bool qcom_scm_hdcp_available(void)
 119 {
 120         int ret = qcom_scm_clk_enable();
 121
 122         if (ret)
 123                 return ret;
 124
 125         ret = __qcom_scm_is_call_available(__scm->dev, QCOM_SCM_SVC_HDCP,
 126                                                 QCOM_SCM_CMD_HDCP);
 127
 128         qcom_scm_clk_disable();
 129
 130         return ret > 0 ? true : false;
 131 }
 132 EXPORT_SYMBOL(qcom_scm_hdcp_available);
 133
 134 /**
 135  * qcom_scm_hdcp_req() - Send HDCP request.
 136  * @req: HDCP request array
 137  * @req_cnt: HDCP request array count
 138  * @resp: response buffer passed to SCM
 139  *
 140  * Write HDCP register(s) through SCM.
 141  */
 142 int qcom_scm_hdcp_req(struct qcom_scm_hdcp_req *req, u32 req_cnt, u32 *resp)
 143 {
 144         int ret = qcom_scm_clk_enable();
 145
 146         if (ret)
 147                 return ret;
 148
 149         ret = __qcom_scm_hdcp_req(__scm->dev, req, req_cnt, resp);
 150         qcom_scm_clk_disable();
 151         return ret;
 152 }
 153 EXPORT_SYMBOL(qcom_scm_hdcp_req);
 154
 155 /**
 156  * qcom_scm_pas_supported() - Check if the peripheral authentication service is
 157  *                            available for the given peripherial
 158  * @peripheral: peripheral id
 159  *
 160  * Returns true if PAS is supported for this peripheral, otherwise false.
 161  */
 162 bool qcom_scm_pas_supported(u32 peripheral)
 163 {
 164         int ret;
 165
 166         ret = __qcom_scm_is_call_available(__scm->dev, QCOM_SCM_SVC_PIL,
 167                                            QCOM_SCM_PAS_IS_SUPPORTED_CMD);
 168         if (ret <= 0)
 169                 return false;
 170
 171         return __qcom_scm_pas_supported(__scm->dev, peripheral);
 172 }
 173 EXPORT_SYMBOL(qcom_scm_pas_supported);
 174
 175 /**
 176  * qcom_scm_pas_init_image() - Initialize peripheral authentication service
 177  *                             state machine for a given peripheral, using the
 178  *                             metadata
 179  * @peripheral: peripheral id
 180  * @metadata:   pointer to memory containing ELF header, program header table
 181  *              and optional blob of data used for authenticating the metadata
 182  *              and the rest of the firmware
 183  * @size:       size of the metadata
 184  *
 185  * Returns 0 on success.
 186  */
 187 int qcom_scm_pas_init_image(u32 peripheral, const void *metadata, size_t size)
 188 {
 189         dma_addr_t mdata_phys;
 190         void *mdata_buf;
 191         int ret;
 192
 193         /*
 194          * During the scm call memory protection will be enabled for the meta
 195          * data blob, so make sure it's physically contiguous, 4K aligned and
 196          * non-cachable to avoid XPU violations.
 197          */
 198         mdata_buf = dma_alloc_coherent(__scm->dev, size, &mdata_phys,
 199                                        GFP_KERNEL);
 200         if (!mdata_buf) {
 201                 dev_err(__scm->dev, "Allocation of metadata buffer failed.\n");
 202                 return -ENOMEM;
 203         }
 204         memcpy(mdata_buf, metadata, size);
 205
 206         ret = qcom_scm_clk_enable();
 207         if (ret)
 208                 goto free_metadata;
 209
 210         ret = __qcom_scm_pas_init_image(__scm->dev, peripheral, mdata_phys);
 211
 212         qcom_scm_clk_disable();
 213
 214 free_metadata:
 215         dma_free_coherent(__scm->dev, size, mdata_buf, mdata_phys);
 216
 217         return ret;
 218 }
 219 EXPORT_SYMBOL(qcom_scm_pas_init_image);
 220
 221 /**
 222  * qcom_scm_pas_mem_setup() - Prepare the memory related to a given peripheral
 223  *                            for firmware loading
 224  * @peripheral: peripheral id
 225  * @addr:       start address of memory area to prepare
 226  * @size:       size of the memory area to prepare
 227  *
 228  * Returns 0 on success.
 229  */
 230 int qcom_scm_pas_mem_setup(u32 peripheral, phys_addr_t addr, phys_addr_t size)
 231 {
 232         int ret;
 233
 234         ret = qcom_scm_clk_enable();
 235         if (ret)
 236                 return ret;
 237
 238         ret = __qcom_scm_pas_mem_setup(__scm->dev, peripheral, addr, size);
 239         qcom_scm_clk_disable();
 240
 241         return ret;
 242 }
 243 EXPORT_SYMBOL(qcom_scm_pas_mem_setup);
 244
 245 /**
 246  * qcom_scm_pas_auth_and_reset() - Authenticate the given peripheral firmware
 247  *                                 and reset the remote processor
 248  * @peripheral: peripheral id
 249  *
 250  * Return 0 on success.
 251  */
 252 int qcom_scm_pas_auth_and_reset(u32 peripheral)
 253 {
 254         int ret;
 255
 256         ret = qcom_scm_clk_enable();
 257         if (ret)
 258                 return ret;
 259
 260         ret = __qcom_scm_pas_auth_and_reset(__scm->dev, peripheral);
 261         qcom_scm_clk_disable();
 262
 263         return ret;
 264 }
 265 EXPORT_SYMBOL(qcom_scm_pas_auth_and_reset);
 266
 267 /**
 268  * qcom_scm_pas_shutdown() - Shut down the remote processor
 269  * @peripheral: peripheral id
 270  *
 271  * Returns 0 on success.
 272  */
 273 int qcom_scm_pas_shutdown(u32 peripheral)
 274 {
 275         int ret;
 276
 277         ret = qcom_scm_clk_enable();
 278         if (ret)
 279                 return ret;
 280
 281         ret = __qcom_scm_pas_shutdown(__scm->dev, peripheral);
 282         qcom_scm_clk_disable();
 283
 284         return ret;
 285 }
 286 EXPORT_SYMBOL(qcom_scm_pas_shutdown);
 287
 288 static int qcom_scm_pas_reset_assert(struct reset_controller_dev *rcdev,
 289                                      unsigned long idx)
 290 {
 291         if (idx != 0)
 292                 return -EINVAL;
 293
 294         return __qcom_scm_pas_mss_reset(__scm->dev, 1);
 295 }
 296
 297 static int qcom_scm_pas_reset_deassert(struct reset_controller_dev *rcdev,
 298                                        unsigned long idx)
 299 {
 300         if (idx != 0)
 301                 return -EINVAL;
 302
 303         return __qcom_scm_pas_mss_reset(__scm->dev, 0);
 304 }
 305
 306 static const struct reset_control_ops qcom_scm_pas_reset_ops = {
 307         .assert = qcom_scm_pas_reset_assert,
 308         .deassert = qcom_scm_pas_reset_deassert,
 309 };
 310
 311 /**
 312  * qcom_scm_is_available() - Checks if SCM is available
 313  */
 314 bool qcom_scm_is_available(void)
 315 {
 316         return !!__scm;
 317 }
 318 EXPORT_SYMBOL(qcom_scm_is_available);
 319
 320 static int qcom_scm_probe(struct platform_device *pdev)
 321 {
 322         struct qcom_scm *scm;
 323         int ret;
 324
 325         scm = devm_kzalloc(&pdev->dev, sizeof(*scm), GFP_KERNEL);
 326         if (!scm)
 327                 return -ENOMEM;
 328
 329         scm->core_clk = devm_clk_get(&pdev->dev, "core");
 330         if (IS_ERR(scm->core_clk)) {
 331                 if (PTR_ERR(scm->core_clk) == -EPROBE_DEFER)
 332                         return PTR_ERR(scm->core_clk);
 333
 334                 scm->core_clk = NULL;
 335         }
 336
 337         if (of_device_is_compatible(pdev->dev.of_node, "qcom,scm")) {
 338                 scm->iface_clk = devm_clk_get(&pdev->dev, "iface");
 339                 if (IS_ERR(scm->iface_clk)) {
 340                         if (PTR_ERR(scm->iface_clk) != -EPROBE_DEFER)
 341                                 dev_err(&pdev->dev, "failed to acquire iface clk\n");
 342                         return PTR_ERR(scm->iface_clk);
 343                 }
 344
 345                 scm->bus_clk = devm_clk_get(&pdev->dev, "bus");
 346                 if (IS_ERR(scm->bus_clk)) {
 347                         if (PTR_ERR(scm->bus_clk) != -EPROBE_DEFER)
 348                                 dev_err(&pdev->dev, "failed to acquire bus clk\n");
 349                         return PTR_ERR(scm->bus_clk);
 350                 }
 351         }
 352
 353         scm->reset.ops = &qcom_scm_pas_reset_ops;
 354         scm->reset.nr_resets = 1;
 355         scm->reset.of_node = pdev->dev.of_node;
 356         reset_controller_register(&scm->reset);
 357
 358         /* vote for max clk rate for highest performance */
 359         ret = clk_set_rate(scm->core_clk, INT_MAX);
 360         if (ret)
 361                 return ret;
 362
 363         __scm = scm;
 364         __scm->dev = &pdev->dev;
 365
 366         __qcom_scm_init();
 367
 368         return 0;
 369 }
 370
 371 static const struct of_device_id qcom_scm_dt_match[] = {
 372         { .compatible = "qcom,scm-apq8064",},
 373         { .compatible = "qcom,scm-msm8660",},
 374         { .compatible = "qcom,scm-msm8960",},
 375         { .compatible = "qcom,scm",},
 376         {}
 377 };
 378
 379 MODULE_DEVICE_TABLE(of, qcom_scm_dt_match);
 380
 381 static struct platform_driver qcom_scm_driver = {
 382         .driver = {
 383                 .name   = "qcom_scm",
 384                 .of_match_table = qcom_scm_dt_match,
 385         },
 386         .probe = qcom_scm_probe,
 387 };
 388
 389 static int __init qcom_scm_init(void)
 390 {
 391         struct device_node *np, *fw_np;
 392         int ret;
 393
 394         fw_np = of_find_node_by_name(NULL, "firmware");
 395
 396         if (!fw_np)
 397                 return -ENODEV;
 398
 399         np = of_find_matching_node(fw_np, qcom_scm_dt_match);
 400
 401         if (!np) {
 402                 of_node_put(fw_np);
 403                 return -ENODEV;
 404         }
 405
 406         of_node_put(np);
 407
 408         ret = of_platform_populate(fw_np, qcom_scm_dt_match, NULL, NULL);
 409
 410         of_node_put(fw_np);
 411
 412         if (ret)
 413                 return ret;
 414
 415         return platform_driver_register(&qcom_scm_driver);
 416 }
 417
 418 subsys_initcall(qcom_scm_init);
 419
 420 static void __exit qcom_scm_exit(void)
 421 {
 422         platform_driver_unregister(&qcom_scm_driver);
 423 }
 424 module_exit(qcom_scm_exit);
 425
 426 MODULE_DESCRIPTION("Qualcomm SCM driver");
 427 MODULE_LICENSE("GPL v2");