diff mbox series

[v5,2/3] iommu/arm-smmu-qcom: Read back stream mappings

Message ID 20201019182323.3162386-3-bjorn.andersson@linaro.org
State New
Headers show
Series iommu/arm-smmu-qcom: Support maintaining bootloader mappings | expand

Commit Message

Bjorn Andersson Oct. 19, 2020, 6:23 p.m. UTC
The Qualcomm boot loader configures stream mapping for the peripherals
that it accesses and in particular it sets up the stream mapping for the
display controller to be allowed to scan out a splash screen or EFI
framebuffer.

Read back the stream mappings during initialization and make the
arm-smmu driver maintain the streams in bypass mode.

Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
---

Changes since v4:
- Don't increment s2cr[i]->count, as this is not actually needed to survive
  probe deferral

 drivers/iommu/arm/arm-smmu/arm-smmu-qcom.c | 23 ++++++++++++++++++++++
 1 file changed, 23 insertions(+)

Comments

Robin Murphy Oct. 19, 2020, 6:50 p.m. UTC | #1
On 2020-10-19 19:23, Bjorn Andersson wrote:
> The Qualcomm boot loader configures stream mapping for the peripherals
> that it accesses and in particular it sets up the stream mapping for the
> display controller to be allowed to scan out a splash screen or EFI
> framebuffer.
> 
> Read back the stream mappings during initialization and make the
> arm-smmu driver maintain the streams in bypass mode.

Acked-by: Robin Murphy <robin.murphy@arm.com>

> Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
> ---
> 
> Changes since v4:
> - Don't increment s2cr[i]->count, as this is not actually needed to survive
>    probe deferral
> 
>   drivers/iommu/arm/arm-smmu/arm-smmu-qcom.c | 23 ++++++++++++++++++++++
>   1 file changed, 23 insertions(+)
> 
> diff --git a/drivers/iommu/arm/arm-smmu/arm-smmu-qcom.c b/drivers/iommu/arm/arm-smmu/arm-smmu-qcom.c
> index be4318044f96..48627fcf6bed 100644
> --- a/drivers/iommu/arm/arm-smmu/arm-smmu-qcom.c
> +++ b/drivers/iommu/arm/arm-smmu/arm-smmu-qcom.c
> @@ -23,6 +23,28 @@ static const struct of_device_id qcom_smmu_client_of_match[] __maybe_unused = {
>   	{ }
>   };
>   
> +static int qcom_smmu_cfg_probe(struct arm_smmu_device *smmu)
> +{
> +	u32 smr;
> +	int i;
> +
> +	for (i = 0; i < smmu->num_mapping_groups; i++) {
> +		smr = arm_smmu_gr0_read(smmu, ARM_SMMU_GR0_SMR(i));
> +
> +		if (FIELD_GET(ARM_SMMU_SMR_VALID, smr)) {
> +			smmu->smrs[i].id = FIELD_GET(ARM_SMMU_SMR_ID, smr);
> +			smmu->smrs[i].mask = FIELD_GET(ARM_SMMU_SMR_MASK, smr);
> +			smmu->smrs[i].valid = true;
> +
> +			smmu->s2crs[i].type = S2CR_TYPE_BYPASS;
> +			smmu->s2crs[i].privcfg = S2CR_PRIVCFG_DEFAULT;
> +			smmu->s2crs[i].cbndx = 0xff;
> +		}
> +	}
> +
> +	return 0;
> +}
> +
>   static int qcom_smmu_def_domain_type(struct device *dev)
>   {
>   	const struct of_device_id *match =
> @@ -61,6 +83,7 @@ static int qcom_smmu500_reset(struct arm_smmu_device *smmu)
>   }
>   
>   static const struct arm_smmu_impl qcom_smmu_impl = {
> +	.cfg_probe = qcom_smmu_cfg_probe,
>   	.def_domain_type = qcom_smmu_def_domain_type,
>   	.reset = qcom_smmu500_reset,
>   };
>
diff mbox series

Patch

diff --git a/drivers/iommu/arm/arm-smmu/arm-smmu-qcom.c b/drivers/iommu/arm/arm-smmu/arm-smmu-qcom.c
index be4318044f96..48627fcf6bed 100644
--- a/drivers/iommu/arm/arm-smmu/arm-smmu-qcom.c
+++ b/drivers/iommu/arm/arm-smmu/arm-smmu-qcom.c
@@ -23,6 +23,28 @@  static const struct of_device_id qcom_smmu_client_of_match[] __maybe_unused = {
 	{ }
 };
 
+static int qcom_smmu_cfg_probe(struct arm_smmu_device *smmu)
+{
+	u32 smr;
+	int i;
+
+	for (i = 0; i < smmu->num_mapping_groups; i++) {
+		smr = arm_smmu_gr0_read(smmu, ARM_SMMU_GR0_SMR(i));
+
+		if (FIELD_GET(ARM_SMMU_SMR_VALID, smr)) {
+			smmu->smrs[i].id = FIELD_GET(ARM_SMMU_SMR_ID, smr);
+			smmu->smrs[i].mask = FIELD_GET(ARM_SMMU_SMR_MASK, smr);
+			smmu->smrs[i].valid = true;
+
+			smmu->s2crs[i].type = S2CR_TYPE_BYPASS;
+			smmu->s2crs[i].privcfg = S2CR_PRIVCFG_DEFAULT;
+			smmu->s2crs[i].cbndx = 0xff;
+		}
+	}
+
+	return 0;
+}
+
 static int qcom_smmu_def_domain_type(struct device *dev)
 {
 	const struct of_device_id *match =
@@ -61,6 +83,7 @@  static int qcom_smmu500_reset(struct arm_smmu_device *smmu)
 }
 
 static const struct arm_smmu_impl qcom_smmu_impl = {
+	.cfg_probe = qcom_smmu_cfg_probe,
 	.def_domain_type = qcom_smmu_def_domain_type,
 	.reset = qcom_smmu500_reset,
 };