drivers/firmware/qcom_scm.c

   1 /*
   2  * Qualcomm SCM driver
   3  *
   4  * Copyright (c) 2010,2015, The Linux Foundation. All rights reserved.
   5  * Copyright (C) 2015 Linaro Ltd.
   6  *
   7  * This program is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License version 2 and
   9  * only version 2 as published by the Free Software Foundation.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  * GNU General Public License for more details.
  15  *
  16  */
  17 #include <linux/platform_device.h>
  18 #include <linux/init.h>
  19 #include <linux/cpumask.h>
  20 #include <linux/export.h>
  21 #include <linux/dma-mapping.h>
  22 #include <linux/types.h>
  23 #include <linux/qcom_scm.h>
  24 #include <linux/of.h>
  25 #include <linux/of_platform.h>
  26 #include <linux/clk.h>
  27 #include <linux/reset-controller.h>
  28
  29 #include "qcom_scm.h"
  30
  31 #define SCM_HAS_CORE_CLK        BIT(0)
  32 #define SCM_HAS_IFACE_CLK       BIT(1)
  33 #define SCM_HAS_BUS_CLK         BIT(2)
  34
  35 struct qcom_scm {
  36         struct device *dev;
  37         struct clk *core_clk;
  38         struct clk *iface_clk;
  39         struct clk *bus_clk;
  40         struct reset_controller_dev reset;
  41 };
  42
  43 static struct qcom_scm *__scm;
  44
  45 static int qcom_scm_clk_enable(void)
  46 {
  47         int ret;
  48
  49         ret = clk_prepare_enable(__scm->core_clk);
  50         if (ret)
  51                 goto bail;
  52
  53         ret = clk_prepare_enable(__scm->iface_clk);
  54         if (ret)
  55                 goto disable_core;
  56
  57         ret = clk_prepare_enable(__scm->bus_clk);
  58         if (ret)
  59                 goto disable_iface;
  60
  61         return 0;
  62
  63 disable_iface:
  64         clk_disable_unprepare(__scm->iface_clk);
  65 disable_core:
  66         clk_disable_unprepare(__scm->core_clk);
  67 bail:
  68         return ret;
  69 }
  70
  71 static void qcom_scm_clk_disable(void)
  72 {
  73         clk_disable_unprepare(__scm->core_clk);
  74         clk_disable_unprepare(__scm->iface_clk);
  75         clk_disable_unprepare(__scm->bus_clk);
  76 }
  77
  78 /**
  79  * qcom_scm_set_cold_boot_addr() - Set the cold boot address for cpus
  80  * @entry: Entry point function for the cpus
  81  * @cpus: The cpumask of cpus that will use the entry point
  82  *
  83  * Set the cold boot address of the cpus. Any cpu outside the supported
  84  * range would be removed from the cpu present mask.
  85  */
  86 int qcom_scm_set_cold_boot_addr(void *entry, const cpumask_t *cpus)
  87 {
  88         return __qcom_scm_set_cold_boot_addr(entry, cpus);
  89 }
  90 EXPORT_SYMBOL(qcom_scm_set_cold_boot_addr);
  91
  92 /**
  93  * qcom_scm_set_warm_boot_addr() - Set the warm boot address for cpus
  94  * @entry: Entry point function for the cpus
  95  * @cpus: The cpumask of cpus that will use the entry point
  96  *
  97  * Set the Linux entry point for the SCM to transfer control to when coming
  98  * out of a power down. CPU power down may be executed on cpuidle or hotplug.
  99  */
 100 int qcom_scm_set_warm_boot_addr(void *entry, const cpumask_t *cpus)
 101 {
 102         return __qcom_scm_set_warm_boot_addr(__scm->dev, entry, cpus);
 103 }
 104 EXPORT_SYMBOL(qcom_scm_set_warm_boot_addr);
 105
 106 /**
 107  * qcom_scm_cpu_power_down() - Power down the cpu
 108  * @flags - Flags to flush cache
 109  *
 110  * This is an end point to power down cpu. If there was a pending interrupt,
 111  * the control would return from this function, otherwise, the cpu jumps to the
 112  * warm boot entry point set for this cpu upon reset.
 113  */
 114 void qcom_scm_cpu_power_down(u32 flags)
 115 {
 116         __qcom_scm_cpu_power_down(flags);
 117 }
 118 EXPORT_SYMBOL(qcom_scm_cpu_power_down);
 119
 120 /**
 121  * qcom_scm_hdcp_available() - Check if secure environment supports HDCP.
 122  *
 123  * Return true if HDCP is supported, false if not.
 124  */
 125 bool qcom_scm_hdcp_available(void)
 126 {
 127         int ret = qcom_scm_clk_enable();
 128
 129         if (ret)
 130                 return ret;
 131
 132         ret = __qcom_scm_is_call_available(__scm->dev, QCOM_SCM_SVC_HDCP,
 133                                                 QCOM_SCM_CMD_HDCP);
 134
 135         qcom_scm_clk_disable();
 136
 137         return ret > 0 ? true : false;
 138 }
 139 EXPORT_SYMBOL(qcom_scm_hdcp_available);
 140
 141 /**
 142  * qcom_scm_hdcp_req() - Send HDCP request.
 143  * @req: HDCP request array
 144  * @req_cnt: HDCP request array count
 145  * @resp: response buffer passed to SCM
 146  *
 147  * Write HDCP register(s) through SCM.
 148  */
 149 int qcom_scm_hdcp_req(struct qcom_scm_hdcp_req *req, u32 req_cnt, u32 *resp)
 150 {
 151         int ret = qcom_scm_clk_enable();
 152
 153         if (ret)
 154                 return ret;
 155
 156         ret = __qcom_scm_hdcp_req(__scm->dev, req, req_cnt, resp);
 157         qcom_scm_clk_disable();
 158         return ret;
 159 }
 160 EXPORT_SYMBOL(qcom_scm_hdcp_req);
 161
 162 /**
 163  * qcom_scm_pas_supported() - Check if the peripheral authentication service is
 164  *                            available for the given peripherial
 165  * @peripheral: peripheral id
 166  *
 167  * Returns true if PAS is supported for this peripheral, otherwise false.
 168  */
 169 bool qcom_scm_pas_supported(u32 peripheral)
 170 {
 171         int ret;
 172
 173         ret = __qcom_scm_is_call_available(__scm->dev, QCOM_SCM_SVC_PIL,
 174                                            QCOM_SCM_PAS_IS_SUPPORTED_CMD);
 175         if (ret <= 0)
 176                 return false;
 177
 178         return __qcom_scm_pas_supported(__scm->dev, peripheral);
 179 }
 180 EXPORT_SYMBOL(qcom_scm_pas_supported);
 181
 182 /**
 183  * qcom_scm_pas_init_image() - Initialize peripheral authentication service
 184  *                             state machine for a given peripheral, using the
 185  *                             metadata
 186  * @peripheral: peripheral id
 187  * @metadata:   pointer to memory containing ELF header, program header table
 188  *              and optional blob of data used for authenticating the metadata
 189  *              and the rest of the firmware
 190  * @size:       size of the metadata
 191  *
 192  * Returns 0 on success.
 193  */
 194 int qcom_scm_pas_init_image(u32 peripheral, const void *metadata, size_t size)
 195 {
 196         dma_addr_t mdata_phys;
 197         void *mdata_buf;
 198         int ret;
 199
 200         /*
 201          * During the scm call memory protection will be enabled for the meta
 202          * data blob, so make sure it's physically contiguous, 4K aligned and
 203          * non-cachable to avoid XPU violations.
 204          */
 205         mdata_buf = dma_alloc_coherent(__scm->dev, size, &mdata_phys,
 206                                        GFP_KERNEL);
 207         if (!mdata_buf) {
 208                 dev_err(__scm->dev, "Allocation of metadata buffer failed.\n");
 209                 return -ENOMEM;
 210         }
 211         memcpy(mdata_buf, metadata, size);
 212
 213         ret = qcom_scm_clk_enable();
 214         if (ret)
 215                 goto free_metadata;
 216
 217         ret = __qcom_scm_pas_init_image(__scm->dev, peripheral, mdata_phys);
 218
 219         qcom_scm_clk_disable();
 220
 221 free_metadata:
 222         dma_free_coherent(__scm->dev, size, mdata_buf, mdata_phys);
 223
 224         return ret;
 225 }
 226 EXPORT_SYMBOL(qcom_scm_pas_init_image);
 227
 228 /**
 229  * qcom_scm_pas_mem_setup() - Prepare the memory related to a given peripheral
 230  *                            for firmware loading
 231  * @peripheral: peripheral id
 232  * @addr:       start address of memory area to prepare
 233  * @size:       size of the memory area to prepare
 234  *
 235  * Returns 0 on success.
 236  */
 237 int qcom_scm_pas_mem_setup(u32 peripheral, phys_addr_t addr, phys_addr_t size)
 238 {
 239         int ret;
 240
 241         ret = qcom_scm_clk_enable();
 242         if (ret)
 243                 return ret;
 244
 245         ret = __qcom_scm_pas_mem_setup(__scm->dev, peripheral, addr, size);
 246         qcom_scm_clk_disable();
 247
 248         return ret;
 249 }
 250 EXPORT_SYMBOL(qcom_scm_pas_mem_setup);
 251
 252 /**
 253  * qcom_scm_pas_auth_and_reset() - Authenticate the given peripheral firmware
 254  *                                 and reset the remote processor
 255  * @peripheral: peripheral id
 256  *
 257  * Return 0 on success.
 258  */
 259 int qcom_scm_pas_auth_and_reset(u32 peripheral)
 260 {
 261         int ret;
 262
 263         ret = qcom_scm_clk_enable();
 264         if (ret)
 265                 return ret;
 266
 267         ret = __qcom_scm_pas_auth_and_reset(__scm->dev, peripheral);
 268         qcom_scm_clk_disable();
 269
 270         return ret;
 271 }
 272 EXPORT_SYMBOL(qcom_scm_pas_auth_and_reset);
 273
 274 /**
 275  * qcom_scm_pas_shutdown() - Shut down the remote processor
 276  * @peripheral: peripheral id
 277  *
 278  * Returns 0 on success.
 279  */
 280 int qcom_scm_pas_shutdown(u32 peripheral)
 281 {
 282         int ret;
 283
 284         ret = qcom_scm_clk_enable();
 285         if (ret)
 286                 return ret;
 287
 288         ret = __qcom_scm_pas_shutdown(__scm->dev, peripheral);
 289         qcom_scm_clk_disable();
 290
 291         return ret;
 292 }
 293 EXPORT_SYMBOL(qcom_scm_pas_shutdown);
 294
 295 static int qcom_scm_pas_reset_assert(struct reset_controller_dev *rcdev,
 296                                      unsigned long idx)
 297 {
 298         if (idx != 0)
 299                 return -EINVAL;
 300
 301         return __qcom_scm_pas_mss_reset(__scm->dev, 1);
 302 }
 303
 304 static int qcom_scm_pas_reset_deassert(struct reset_controller_dev *rcdev,
 305                                        unsigned long idx)
 306 {
 307         if (idx != 0)
 308                 return -EINVAL;
 309
 310         return __qcom_scm_pas_mss_reset(__scm->dev, 0);
 311 }
 312
 313 static const struct reset_control_ops qcom_scm_pas_reset_ops = {
 314         .assert = qcom_scm_pas_reset_assert,
 315         .deassert = qcom_scm_pas_reset_deassert,
 316 };
 317
 318 /**
 319  * qcom_scm_is_available() - Checks if SCM is available
 320  */
 321 bool qcom_scm_is_available(void)
 322 {
 323         return !!__scm;
 324 }
 325 EXPORT_SYMBOL(qcom_scm_is_available);
 326
 327 static int qcom_scm_probe(struct platform_device *pdev)
 328 {
 329         struct qcom_scm *scm;
 330         unsigned long clks;
 331         int ret;
 332
 333         scm = devm_kzalloc(&pdev->dev, sizeof(*scm), GFP_KERNEL);
 334         if (!scm)
 335                 return -ENOMEM;
 336
 337         clks = (unsigned long)of_device_get_match_data(&pdev->dev);
 338         if (clks & SCM_HAS_CORE_CLK) {
 339                 scm->core_clk = devm_clk_get(&pdev->dev, "core");
 340                 if (IS_ERR(scm->core_clk)) {
 341                         if (PTR_ERR(scm->core_clk) != -EPROBE_DEFER)
 342                                 dev_err(&pdev->dev,
 343                                         "failed to acquire core clk\n");
 344                         return PTR_ERR(scm->core_clk);
 345                 }
 346         }
 347
 348         if (clks & SCM_HAS_IFACE_CLK) {
 349                 scm->iface_clk = devm_clk_get(&pdev->dev, "iface");
 350                 if (IS_ERR(scm->iface_clk)) {
 351                         if (PTR_ERR(scm->iface_clk) != -EPROBE_DEFER)
 352                                 dev_err(&pdev->dev,
 353                                         "failed to acquire iface clk\n");
 354                         return PTR_ERR(scm->iface_clk);
 355                 }
 356         }
 357
 358         if (clks & SCM_HAS_BUS_CLK) {
 359                 scm->bus_clk = devm_clk_get(&pdev->dev, "bus");
 360                 if (IS_ERR(scm->bus_clk)) {
 361                         if (PTR_ERR(scm->bus_clk) != -EPROBE_DEFER)
 362                                 dev_err(&pdev->dev,
 363                                         "failed to acquire bus clk\n");
 364                         return PTR_ERR(scm->bus_clk);
 365                 }
 366         }
 367
 368         scm->reset.ops = &qcom_scm_pas_reset_ops;
 369         scm->reset.nr_resets = 1;
 370         scm->reset.of_node = pdev->dev.of_node;
 371         ret = devm_reset_controller_register(&pdev->dev, &scm->reset);
 372         if (ret)
 373                 return ret;
 374
 375         /* vote for max clk rate for highest performance */
 376         ret = clk_set_rate(scm->core_clk, INT_MAX);
 377         if (ret)
 378                 return ret;
 379
 380         __scm = scm;
 381         __scm->dev = &pdev->dev;
 382
 383         __qcom_scm_init();
 384
 385         return 0;
 386 }
 387
 388 static const struct of_device_id qcom_scm_dt_match[] = {
 389         { .compatible = "qcom,scm-apq8064",
 390           .data = (void *) SCM_HAS_CORE_CLK,
 391         },
 392         { .compatible = "qcom,scm-msm8660",
 393           .data = (void *) SCM_HAS_CORE_CLK,
 394         },
 395         { .compatible = "qcom,scm-msm8960",
 396           .data = (void *) SCM_HAS_CORE_CLK,
 397         },
 398         { .compatible = "qcom,scm-msm8996",
 399           .data = NULL, /* no clocks */
 400         },
 401         { .compatible = "qcom,scm",
 402           .data = (void *)(SCM_HAS_CORE_CLK
 403                            | SCM_HAS_IFACE_CLK
 404                            | SCM_HAS_BUS_CLK),
 405         },
 406         {}
 407 };
 408
 409 static struct platform_driver qcom_scm_driver = {
 410         .driver = {
 411                 .name   = "qcom_scm",
 412                 .of_match_table = qcom_scm_dt_match,
 413         },
 414         .probe = qcom_scm_probe,
 415 };
 416
 417 static int __init qcom_scm_init(void)
 418 {
 419         struct device_node *np, *fw_np;
 420         int ret;
 421
 422         fw_np = of_find_node_by_name(NULL, "firmware");
 423
 424         if (!fw_np)
 425                 return -ENODEV;
 426
 427         np = of_find_matching_node(fw_np, qcom_scm_dt_match);
 428
 429         if (!np) {
 430                 of_node_put(fw_np);
 431                 return -ENODEV;
 432         }
 433
 434         of_node_put(np);
 435
 436         ret = of_platform_populate(fw_np, qcom_scm_dt_match, NULL, NULL);
 437
 438         of_node_put(fw_np);
 439
 440         if (ret)
 441                 return ret;
 442
 443         return platform_driver_register(&qcom_scm_driver);
 444 }
 445 subsys_initcall(qcom_scm_init);