drivers/crypto/ccree/cc_pm.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /* Copyright (C) 2012-2019 ARM Limited (or its affiliates). */
   3
   4 #include <linux/kernel.h>
   5 #include <linux/interrupt.h>
   6 #include <linux/pm_runtime.h>
   7 #include "cc_driver.h"
   8 #include "cc_buffer_mgr.h"
   9 #include "cc_request_mgr.h"
  10 #include "cc_sram_mgr.h"
  11 #include "cc_hash.h"
  12 #include "cc_pm.h"
  13 #include "cc_fips.h"
  14
  15 #define POWER_DOWN_ENABLE 0x01
  16 #define POWER_DOWN_DISABLE 0x00
  17
  18 const struct dev_pm_ops ccree_pm = {
  19         SET_RUNTIME_PM_OPS(cc_pm_suspend, cc_pm_resume, NULL)
  20 };
  21
  22 int cc_pm_suspend(struct device *dev)
  23 {
  24         struct cc_drvdata *drvdata = dev_get_drvdata(dev);
  25         int rc;
  26
  27         dev_dbg(dev, "set HOST_POWER_DOWN_EN\n");
  28         rc = cc_suspend_req_queue(drvdata);
  29         if (rc) {
  30                 dev_err(dev, "cc_suspend_req_queue (%x)\n", rc);
  31                 return rc;
  32         }
  33         fini_cc_regs(drvdata);
  34         cc_iowrite(drvdata, CC_REG(HOST_POWER_DOWN_EN), POWER_DOWN_ENABLE);
  35         cc_clk_off(drvdata);
  36         return 0;
  37 }
  38
  39 int cc_pm_resume(struct device *dev)
  40 {
  41         int rc;
  42         struct cc_drvdata *drvdata = dev_get_drvdata(dev);
  43
  44         dev_dbg(dev, "unset HOST_POWER_DOWN_EN\n");
  45         /* Enables the device source clk */
  46         rc = cc_clk_on(drvdata);
  47         if (rc) {
  48                 dev_err(dev, "failed getting clock back on. We're toast.\n");
  49                 return rc;
  50         }
  51         /* wait for Crytpcell reset completion */
  52         if (!cc_wait_for_reset_completion(drvdata)) {
  53                 dev_err(dev, "Cryptocell reset not completed");
  54                 return -EBUSY;
  55         }
  56
  57         cc_iowrite(drvdata, CC_REG(HOST_POWER_DOWN_EN), POWER_DOWN_DISABLE);
  58         rc = init_cc_regs(drvdata, false);
  59         if (rc) {
  60                 dev_err(dev, "init_cc_regs (%x)\n", rc);
  61                 return rc;
  62         }
  63         /* check if tee fips error occurred during power down */
  64         cc_tee_handle_fips_error(drvdata);
  65
  66         rc = cc_resume_req_queue(drvdata);
  67         if (rc) {
  68                 dev_err(dev, "cc_resume_req_queue (%x)\n", rc);
  69                 return rc;
  70         }
  71
  72         /* must be after the queue resuming as it uses the HW queue*/
  73         cc_init_hash_sram(drvdata);
  74
  75         return 0;
  76 }
  77
  78 int cc_pm_get(struct device *dev)
  79 {
  80         int rc = 0;
  81         struct cc_drvdata *drvdata = dev_get_drvdata(dev);
  82
  83         if (cc_req_queue_suspended(drvdata))
  84                 rc = pm_runtime_get_sync(dev);
  85         else
  86                 pm_runtime_get_noresume(dev);
  87
  88         return rc;
  89 }
  90
  91 int cc_pm_put_suspend(struct device *dev)
  92 {
  93         int rc = 0;
  94         struct cc_drvdata *drvdata = dev_get_drvdata(dev);
  95
  96         if (!cc_req_queue_suspended(drvdata)) {
  97                 pm_runtime_mark_last_busy(dev);
  98                 rc = pm_runtime_put_autosuspend(dev);
  99         } else {
 100                 /* Something wrong happens*/
 101                 dev_err(dev, "request to suspend already suspended queue");
 102                 rc = -EBUSY;
 103         }
 104         return rc;
 105 }
 106
 107 bool cc_pm_is_dev_suspended(struct device *dev)
 108 {
 109         /* check device state using runtime api */
 110         return pm_runtime_suspended(dev);
 111 }
 112
 113 int cc_pm_init(struct cc_drvdata *drvdata)
 114 {
 115         struct device *dev = drvdata_to_dev(drvdata);
 116
 117         /* must be before the enabling to avoid resdundent suspending */
 118         pm_runtime_set_autosuspend_delay(dev, CC_SUSPEND_TIMEOUT);
 119         pm_runtime_use_autosuspend(dev);
 120         /* activate the PM module */
 121         return pm_runtime_set_active(dev);
 122 }
 123
 124 /* enable the PM module*/
 125 void cc_pm_go(struct cc_drvdata *drvdata)
 126 {
 127         pm_runtime_enable(drvdata_to_dev(drvdata));
 128 }
 129
 130 void cc_pm_fini(struct cc_drvdata *drvdata)
 131 {
 132         pm_runtime_disable(drvdata_to_dev(drvdata));
 133 }