Re: [PATCH 7/8] remoteproc: qcom: Add support for memory sandbox

[Dmitry Baryshkov <dmitry.baryshkov@linaro.org>]

On 03/08/2022 17:21, Srinivasa Rao Mandadapu wrote:
> Add memory sandbox support for ADSP based platforms secure booting.

This repeats commit subject. Please replace it with proper commit 
message text describing what is done and why.

> 
> Signed-off-by: Srinivasa Rao Mandadapu <quic_srivasam@quicinc.com>
> ---
>   drivers/remoteproc/qcom_q6v5_adsp.c | 101 +++++++++++++++++++++++++++++++++++-
>   1 file changed, 99 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/remoteproc/qcom_q6v5_adsp.c b/drivers/remoteproc/qcom_q6v5_adsp.c
> index 3dbd035..f81da47 100644
> --- a/drivers/remoteproc/qcom_q6v5_adsp.c
> +++ b/drivers/remoteproc/qcom_q6v5_adsp.c
> @@ -9,6 +9,7 @@
>   #include <linux/firmware.h>
>   #include <linux/interrupt.h>
>   #include <linux/io.h>
> +#include <linux/iommu.h>
>   #include <linux/iopoll.h>
>   #include <linux/kernel.h>
>   #include <linux/mfd/syscon.h>
> @@ -48,6 +49,8 @@
>   #define LPASS_PWR_ON_REG		0x10
>   #define LPASS_HALTREQ_REG		0x0
>   
> +#define SID_MASK_DEFAULT        0xF
> +
>   #define QDSP6SS_XO_CBCR		0x38
>   #define QDSP6SS_CORE_CBCR	0x20
>   #define QDSP6SS_SLEEP_CBCR	0x3c
> @@ -77,7 +80,7 @@ struct adsp_pil_data {
>   struct qcom_adsp {
>   	struct device *dev;
>   	struct rproc *rproc;
> -
> +	struct iommu_domain *iommu_dom;
>   	struct qcom_q6v5 q6v5;
>   
>   	struct clk *xo;
> @@ -332,6 +335,91 @@ static int adsp_load(struct rproc *rproc, const struct firmware *fw)
>   	return 0;
>   }
>   
> +static int adsp_map_smmu(struct qcom_adsp *adsp, struct rproc *rproc)
> +{
> +	struct of_phandle_args args;
> +	int ret, rc, i;
> +	long long sid;
> +
> +	unsigned long mem_phys;
> +	unsigned long iova;
> +	const __be32 *prop;
> +	int access_level;
> +	uint32_t len, flag, mem_size;
> +	int offset;
> +	struct fw_rsc_hdr *hdr;
> +	struct fw_rsc_devmem *rsc_fw;
> +
> +	rc = of_parse_phandle_with_fixed_args(adsp->dev->of_node, "iommus", 1, 0, &args);

Please do not add implicit dependency on #iommu-cells value.

> +	if (rc < 0)
> +		sid = -1;
> +	else
> +		sid = args.args[0] & SID_MASK_DEFAULT;
> +
> +	adsp->iommu_dom = iommu_domain_alloc(&platform_bus_type);

please use adsp->dev->bus instead of platform_bus_type here.

> +	if (!adsp->iommu_dom) {
> +		dev_err(adsp->dev, "failed to allocate iommu domain\n");
> +		return -ENOMEM;
> +	}
> +
> +	ret = iommu_attach_device(adsp->iommu_dom, adsp->dev);
> +	if (ret) {
> +		dev_err(adsp->dev, "could not attach device ret = %d\n", ret);
> +		return -EBUSY;
> +	}
> +
> +	/* Add SID configuration for ADSP Firmware to SMMU */
> +	adsp->mem_phys =  adsp->mem_phys | (sid << 32);
> +
> +	ret = iommu_map(adsp->iommu_dom, adsp->mem_phys, adsp->mem_phys,
> +			adsp->mem_size,	IOMMU_READ | IOMMU_WRITE);
> +	if (ret) {
> +		dev_err(adsp->dev, "Unable to map ADSP Physical Memory\n");
> +		return ret;
> +	}
> +
> +	prop = of_get_property(adsp->dev->of_node, "qcom,adsp-memory", &len);

Non-documented property. So, this chunk is not acceptable.

> +	if (prop) {
> +		len /= sizeof(__be32);
> +		for (i = 0; i < len; i++) {
> +			iova = be32_to_cpu(prop[i++]);
> +			mem_phys = be32_to_cpu(prop[i++]);
> +			mem_size = be32_to_cpu(prop[i++]);
> +			access_level = be32_to_cpu(prop[i]);
> +
> +			if (access_level)
> +				flag = IOMMU_READ | IOMMU_WRITE;
> +			else
> +				flag = IOMMU_READ;
> +
> +			ret = iommu_map(adsp->iommu_dom, iova, mem_phys, mem_size, flag);
> +			if (ret) {
> +				dev_err(adsp->dev, "failed to map addr = %p mem_size = %x\n",
> +						&(mem_phys), mem_size);
> +				return ret;
> +			}
> +		}
> +	} else {
> +		if (!rproc->table_ptr)
> +			return 0;
> +
> +		for (i = 0; i < rproc->table_ptr->num; i++) {
> +			offset = rproc->table_ptr->offset[i];
> +			hdr = (void *)rproc->table_ptr + offset;
> +			rsc_fw = (struct fw_rsc_devmem *)hdr + sizeof(*hdr);
> +
> +			ret = iommu_map(rproc->domain, rsc_fw->da, rsc_fw->pa,
> +						rsc_fw->len, rsc_fw->flags);

What about filling an sgtable instead and using it?

> +			if (ret) {
> +				pr_err("%s; unable to map adsp memory address\n", __func__);
> +				return ret;
> +			}
> +		}
> +	}
> +	return 0;
> +}
> +
> +
>   static int adsp_start(struct rproc *rproc)
>   {
>   	struct qcom_adsp *adsp = (struct qcom_adsp *)rproc->priv;
> @@ -341,7 +429,13 @@ static int adsp_start(struct rproc *rproc)
>   	ret = qcom_q6v5_prepare(&adsp->q6v5);
>   	if (ret)
>   		return ret;
> -
> +	if (!adsp->is_wpss) {
> +		ret = adsp_map_smmu(adsp, rproc);

Is this also applicable to cDSP? To sdm845 adsp?

> +		if (ret) {
> +			dev_err(adsp->dev, "ADSP smmu mapping failed\n");
> +			goto adsp_smmu_unmap;
> +		}
> +	}
>   	ret = clk_prepare_enable(adsp->xo);
>   	if (ret)
>   		goto disable_irqs;
> @@ -402,6 +496,9 @@ static int adsp_start(struct rproc *rproc)
>   	clk_disable_unprepare(adsp->xo);
>   disable_irqs:
>   	qcom_q6v5_unprepare(&adsp->q6v5);
> +adsp_smmu_unmap:
> +	iommu_unmap(adsp->iommu_dom, adsp->mem_phys, adsp->mem_size);
> +	iommu_domain_free(adsp->iommu_dom);
>   
>   	return ret;
>   }


-- 
With best wishes
Dmitry