drivers/iommu/arm-smmu-qcom.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Copyright (c) 2019, The Linux Foundation. All rights reserved.
   4  */
   5
   6 #include <linux/qcom_scm.h>
   7
   8 #include "arm-smmu.h"
   9
  10 struct qcom_smmu {
  11         struct arm_smmu_device smmu;
  12 };
  13
  14 static int qcom_sdm845_smmu500_reset(struct arm_smmu_device *smmu)
  15 {
  16         int ret;
  17
  18         arm_mmu500_reset(smmu);
  19
  20         /*
  21          * To address performance degradation in non-real time clients,
  22          * such as USB and UFS, turn off wait-for-safe on sdm845 based boards,
  23          * such as MTP and db845, whose firmwares implement secure monitor
  24          * call handlers to turn on/off the wait-for-safe logic.
  25          */
  26         ret = qcom_scm_qsmmu500_wait_safe_toggle(0);
  27         if (ret)
  28                 dev_warn(smmu->dev, "Failed to turn off SAFE logic\n");
  29
  30         return ret;
  31 }
  32
  33 static const struct arm_smmu_impl qcom_smmu_impl = {
  34         .reset = qcom_sdm845_smmu500_reset,
  35 };
  36
  37 struct arm_smmu_device *qcom_smmu_impl_init(struct arm_smmu_device *smmu)
  38 {
  39         struct qcom_smmu *qsmmu;
  40
  41         qsmmu = devm_kzalloc(smmu->dev, sizeof(*qsmmu), GFP_KERNEL);
  42         if (!qsmmu)
  43                 return ERR_PTR(-ENOMEM);
  44
  45         qsmmu->smmu = *smmu;
  46
  47         qsmmu->smmu.impl = &qcom_smmu_impl;
  48         devm_kfree(smmu->dev, smmu);
  49
  50         return &qsmmu->smmu;
  51 }