drivers/crypto/ccree/cc_pm.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /* Copyright (C) 2012-2018 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_ivgen.h"
  12 #include "cc_hash.h"
  13 #include "cc_pm.h"
  14 #include "cc_fips.h"
  15
  16 #define POWER_DOWN_ENABLE 0x01
  17 #define POWER_DOWN_DISABLE 0x00
  18
  19 const struct dev_pm_ops ccree_pm = {
  20         SET_RUNTIME_PM_OPS(cc_pm_suspend, cc_pm_resume, NULL)
  21 };
  22
  23 int cc_pm_suspend(struct device *dev)
  24 {
  25         struct cc_drvdata *drvdata = dev_get_drvdata(dev);
  26
  27         dev_dbg(dev, "set HOST_POWER_DOWN_EN\n");
  28         fini_cc_regs(drvdata);
  29         cc_iowrite(drvdata, CC_REG(HOST_POWER_DOWN_EN), POWER_DOWN_ENABLE);
  30         cc_clk_off(drvdata);
  31         return 0;
  32 }
  33
  34 int cc_pm_resume(struct device *dev)
  35 {
  36         int rc;
  37         struct cc_drvdata *drvdata = dev_get_drvdata(dev);
  38
  39         dev_dbg(dev, "unset HOST_POWER_DOWN_EN\n");
  40         /* Enables the device source clk */
  41         rc = cc_clk_on(drvdata);
  42         if (rc) {
  43                 dev_err(dev, "failed getting clock back on. We're toast.\n");
  44                 return rc;
  45         }
  46
  47         cc_iowrite(drvdata, CC_REG(HOST_POWER_DOWN_EN), POWER_DOWN_DISABLE);
  48         rc = init_cc_regs(drvdata, false);
  49         if (rc) {
  50                 dev_err(dev, "init_cc_regs (%x)\n", rc);
  51                 return rc;
  52         }
  53         /* check if tee fips error occurred during power down */
  54         cc_tee_handle_fips_error(drvdata);
  55
  56         cc_init_hash_sram(drvdata);
  57
  58         cc_init_iv_sram(drvdata);
  59         return 0;
  60 }
  61
  62 int cc_pm_get(struct device *dev)
  63 {
  64         int rc = 0;
  65         struct cc_drvdata *drvdata = dev_get_drvdata(dev);
  66
  67         if (drvdata->pm_on)
  68                 rc = pm_runtime_get_sync(dev);
  69
  70         return (rc == 1 ? 0 : rc);
  71 }
  72
  73 int cc_pm_put_suspend(struct device *dev)
  74 {
  75         int rc = 0;
  76         struct cc_drvdata *drvdata = dev_get_drvdata(dev);
  77
  78         if (drvdata->pm_on) {
  79                 pm_runtime_mark_last_busy(dev);
  80                 rc = pm_runtime_put_autosuspend(dev);
  81         }
  82
  83         return rc;
  84 }
  85
  86 int cc_pm_init(struct cc_drvdata *drvdata)
  87 {
  88         struct device *dev = drvdata_to_dev(drvdata);
  89
  90         /* must be before the enabling to avoid resdundent suspending */
  91         pm_runtime_set_autosuspend_delay(dev, CC_SUSPEND_TIMEOUT);
  92         pm_runtime_use_autosuspend(dev);
  93         /* set us as active - note we won't do PM ops until cc_pm_go()! */
  94         return pm_runtime_set_active(dev);
  95 }
  96
  97 /* enable the PM module*/
  98 void cc_pm_go(struct cc_drvdata *drvdata)
  99 {
 100         pm_runtime_enable(drvdata_to_dev(drvdata));
 101         drvdata->pm_on = true;
 102 }
 103
 104 void cc_pm_fini(struct cc_drvdata *drvdata)
 105 {
 106         pm_runtime_disable(drvdata_to_dev(drvdata));
 107         drvdata->pm_on = false;
 108 }