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/types.h>
  19 #include <linux/qcom_scm.h>
  20 #include <linux/of.h>
  21 #include <linux/of_platform.h>
  22 #include <linux/clk.h>
  23
  24 #include "qcom_scm.h"
  25
  26 struct qcom_scm {
  27         struct device *dev;
  28         struct clk *core_clk;
  29         struct clk *iface_clk;
  30         struct clk *bus_clk;
  31 };
  32
  33 static struct qcom_scm *__scm;
  34
  35 static int qcom_scm_clk_enable(void)
  36 {
  37         int ret;
  38
  39         ret = clk_prepare_enable(__scm->core_clk);
  40         if (ret)
  41                 goto bail;
  42
  43         ret = clk_prepare_enable(__scm->iface_clk);
  44         if (ret)
  45                 goto disable_core;
  46
  47         ret = clk_prepare_enable(__scm->bus_clk);
  48         if (ret)
  49                 goto disable_iface;
  50
  51         return 0;
  52
  53 disable_iface:
  54         clk_disable_unprepare(__scm->iface_clk);
  55 disable_core:
  56         clk_disable_unprepare(__scm->core_clk);
  57 bail:
  58         return ret;
  59 }
  60
  61 static void qcom_scm_clk_disable(void)
  62 {
  63         clk_disable_unprepare(__scm->core_clk);
  64         clk_disable_unprepare(__scm->iface_clk);
  65         clk_disable_unprepare(__scm->bus_clk);
  66 }
  67
  68 /**
  69  * qcom_scm_set_cold_boot_addr() - Set the cold boot address for cpus
  70  * @entry: Entry point function for the cpus
  71  * @cpus: The cpumask of cpus that will use the entry point
  72  *
  73  * Set the cold boot address of the cpus. Any cpu outside the supported
  74  * range would be removed from the cpu present mask.
  75  */
  76 int qcom_scm_set_cold_boot_addr(void *entry, const cpumask_t *cpus)
  77 {
  78         return __qcom_scm_set_cold_boot_addr(entry, cpus);
  79 }
  80 EXPORT_SYMBOL(qcom_scm_set_cold_boot_addr);
  81
  82 /**
  83  * qcom_scm_set_warm_boot_addr() - Set the warm boot address for cpus
  84  * @entry: Entry point function for the cpus
  85  * @cpus: The cpumask of cpus that will use the entry point
  86  *
  87  * Set the Linux entry point for the SCM to transfer control to when coming
  88  * out of a power down. CPU power down may be executed on cpuidle or hotplug.
  89  */
  90 int qcom_scm_set_warm_boot_addr(void *entry, const cpumask_t *cpus)
  91 {
  92         return __qcom_scm_set_warm_boot_addr(__scm->dev, entry, cpus);
  93 }
  94 EXPORT_SYMBOL(qcom_scm_set_warm_boot_addr);
  95
  96 /**
  97  * qcom_scm_cpu_power_down() - Power down the cpu
  98  * @flags - Flags to flush cache
  99  *
 100  * This is an end point to power down cpu. If there was a pending interrupt,
 101  * the control would return from this function, otherwise, the cpu jumps to the
 102  * warm boot entry point set for this cpu upon reset.
 103  */
 104 void qcom_scm_cpu_power_down(u32 flags)
 105 {
 106         __qcom_scm_cpu_power_down(flags);
 107 }
 108 EXPORT_SYMBOL(qcom_scm_cpu_power_down);
 109
 110 /**
 111  * qcom_scm_hdcp_available() - Check if secure environment supports HDCP.
 112  *
 113  * Return true if HDCP is supported, false if not.
 114  */
 115 bool qcom_scm_hdcp_available(void)
 116 {
 117         int ret = qcom_scm_clk_enable();
 118
 119         if (ret)
 120                 return ret;
 121
 122         ret = __qcom_scm_is_call_available(__scm->dev, QCOM_SCM_SVC_HDCP,
 123                                                 QCOM_SCM_CMD_HDCP);
 124
 125         qcom_scm_clk_disable();
 126
 127         return ret > 0 ? true : false;
 128 }
 129 EXPORT_SYMBOL(qcom_scm_hdcp_available);
 130
 131 /**
 132  * qcom_scm_hdcp_req() - Send HDCP request.
 133  * @req: HDCP request array
 134  * @req_cnt: HDCP request array count
 135  * @resp: response buffer passed to SCM
 136  *
 137  * Write HDCP register(s) through SCM.
 138  */
 139 int qcom_scm_hdcp_req(struct qcom_scm_hdcp_req *req, u32 req_cnt, u32 *resp)
 140 {
 141         int ret = qcom_scm_clk_enable();
 142
 143         if (ret)
 144                 return ret;
 145
 146         ret = __qcom_scm_hdcp_req(__scm->dev, req, req_cnt, resp);
 147         qcom_scm_clk_disable();
 148         return ret;
 149 }
 150 EXPORT_SYMBOL(qcom_scm_hdcp_req);
 151
 152 static int qcom_scm_probe(struct platform_device *pdev)
 153 {
 154         struct qcom_scm *scm;
 155         int ret;
 156
 157         scm = devm_kzalloc(&pdev->dev, sizeof(*scm), GFP_KERNEL);
 158         if (!scm)
 159                 return -ENOMEM;
 160
 161         scm->core_clk = devm_clk_get(&pdev->dev, "core");
 162         if (IS_ERR(scm->core_clk)) {
 163                 if (PTR_ERR(scm->core_clk) == -EPROBE_DEFER)
 164                         return PTR_ERR(scm->core_clk);
 165
 166                 scm->core_clk = NULL;
 167         }
 168
 169         if (of_device_is_compatible(pdev->dev.of_node, "qcom,scm")) {
 170                 scm->iface_clk = devm_clk_get(&pdev->dev, "iface");
 171                 if (IS_ERR(scm->iface_clk)) {
 172                         if (PTR_ERR(scm->iface_clk) != -EPROBE_DEFER)
 173                                 dev_err(&pdev->dev, "failed to acquire iface clk\n");
 174                         return PTR_ERR(scm->iface_clk);
 175                 }
 176
 177                 scm->bus_clk = devm_clk_get(&pdev->dev, "bus");
 178                 if (IS_ERR(scm->bus_clk)) {
 179                         if (PTR_ERR(scm->bus_clk) != -EPROBE_DEFER)
 180                                 dev_err(&pdev->dev, "failed to acquire bus clk\n");
 181                         return PTR_ERR(scm->bus_clk);
 182                 }
 183         }
 184
 185         /* vote for max clk rate for highest performance */
 186         ret = clk_set_rate(scm->core_clk, INT_MAX);
 187         if (ret)
 188                 return ret;
 189
 190         __scm = scm;
 191         __scm->dev = &pdev->dev;
 192
 193         __qcom_scm_init();
 194
 195         return 0;
 196 }
 197
 198 static const struct of_device_id qcom_scm_dt_match[] = {
 199         { .compatible = "qcom,scm-apq8064",},
 200         { .compatible = "qcom,scm-msm8660",},
 201         { .compatible = "qcom,scm-msm8960",},
 202         { .compatible = "qcom,scm",},
 203         {}
 204 };
 205
 206 MODULE_DEVICE_TABLE(of, qcom_scm_dt_match);
 207
 208 static struct platform_driver qcom_scm_driver = {
 209         .driver = {
 210                 .name   = "qcom_scm",
 211                 .of_match_table = qcom_scm_dt_match,
 212         },
 213         .probe = qcom_scm_probe,
 214 };
 215
 216 static int __init qcom_scm_init(void)
 217 {
 218         struct device_node *np, *fw_np;
 219         int ret;
 220
 221         fw_np = of_find_node_by_name(NULL, "firmware");
 222
 223         if (!fw_np)
 224                 return -ENODEV;
 225
 226         np = of_find_matching_node(fw_np, qcom_scm_dt_match);
 227
 228         if (!np) {
 229                 of_node_put(fw_np);
 230                 return -ENODEV;
 231         }
 232
 233         of_node_put(np);
 234
 235         ret = of_platform_populate(fw_np, qcom_scm_dt_match, NULL, NULL);
 236
 237         of_node_put(fw_np);
 238
 239         if (ret)
 240                 return ret;
 241
 242         return platform_driver_register(&qcom_scm_driver);
 243 }
 244
 245 arch_initcall(qcom_scm_init);
 246
 247 static void __exit qcom_scm_exit(void)
 248 {
 249         platform_driver_unregister(&qcom_scm_driver);
 250 }
 251 module_exit(qcom_scm_exit);
 252
 253 MODULE_DESCRIPTION("Qualcomm SCM driver");
 254 MODULE_LICENSE("GPL v2");