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