Re: [PATCH RFT 1/2] firmware: qcom: scm: Introduce CP_SMMU_APERTURE_ID

[Jessica Zhang <quic_jesszhan@quicinc.com>]

On 10/2/2024 8:01 PM, Bjorn Andersson wrote:
> The QCOM_SCM_SVC_MP service provides QCOM_SCM_MP_CP_SMMU_APERTURE_ID,
> which is used to trigger the mapping of register banks into the SMMU
> context for per-processes page tables to function (in case this isn't
> statically setup by firmware).
> 
> This is necessary on e.g. QCS6490 Rb3Gen2, in order to avoid "CP | AHB
> bus error"-errors from the GPU.
> 
> Introduce a function to allow the msm driver to invoke this call.
> 
> Signed-off-by: Bjorn Andersson <bjorn.andersson@oss.qualcomm.com>

Hi Bjorn,

Tested-by: Jessica Zhang <quic_jesszhan@quicinc.com> # Trogdor (sc7180)

Thanks,

Jessica Zhang

> ---
>   drivers/firmware/qcom/qcom_scm.c       | 19 +++++++++++++++++++
>   drivers/firmware/qcom/qcom_scm.h       |  1 +
>   include/linux/firmware/qcom/qcom_scm.h |  1 +
>   3 files changed, 21 insertions(+)
> 
> diff --git a/drivers/firmware/qcom/qcom_scm.c b/drivers/firmware/qcom/qcom_scm.c
> index 10986cb11ec0..bd633c57b6e8 100644
> --- a/drivers/firmware/qcom/qcom_scm.c
> +++ b/drivers/firmware/qcom/qcom_scm.c
> @@ -903,6 +903,25 @@ int qcom_scm_restore_sec_cfg(u32 device_id, u32 spare)
>   }
>   EXPORT_SYMBOL_GPL(qcom_scm_restore_sec_cfg);
>   
> +#define QCOM_SCM_CP_APERTURE_CONTEXT_MASK	GENMASK(7, 0)
> +
> +int qcom_scm_set_gpu_smmu_aperture(unsigned int context_bank)
> +{
> +	struct qcom_scm_desc desc = {
> +		.svc = QCOM_SCM_SVC_MP,
> +		.cmd = QCOM_SCM_MP_CP_SMMU_APERTURE_ID,
> +		.arginfo = QCOM_SCM_ARGS(4),
> +		.args[0] = 0xffff0000 | FIELD_PREP(QCOM_SCM_CP_APERTURE_CONTEXT_MASK, context_bank),
> +		.args[1] = 0xffffffff,
> +		.args[2] = 0xffffffff,
> +		.args[3] = 0xffffffff,
> +		.owner = ARM_SMCCC_OWNER_SIP
> +	};
> +
> +	return qcom_scm_call(__scm->dev, &desc, NULL);
> +}
> +EXPORT_SYMBOL_GPL(qcom_scm_set_gpu_smmu_aperture);
> +
>   int qcom_scm_iommu_secure_ptbl_size(u32 spare, size_t *size)
>   {
>   	struct qcom_scm_desc desc = {
> diff --git a/drivers/firmware/qcom/qcom_scm.h b/drivers/firmware/qcom/qcom_scm.h
> index 685b8f59e7a6..e36b2f67607f 100644
> --- a/drivers/firmware/qcom/qcom_scm.h
> +++ b/drivers/firmware/qcom/qcom_scm.h
> @@ -116,6 +116,7 @@ struct qcom_tzmem_pool *qcom_scm_get_tzmem_pool(void);
>   #define QCOM_SCM_MP_IOMMU_SET_CP_POOL_SIZE	0x05
>   #define QCOM_SCM_MP_VIDEO_VAR			0x08
>   #define QCOM_SCM_MP_ASSIGN			0x16
> +#define QCOM_SCM_MP_CP_SMMU_APERTURE_ID		0x1b
>   #define QCOM_SCM_MP_SHM_BRIDGE_ENABLE		0x1c
>   #define QCOM_SCM_MP_SHM_BRIDGE_DELETE		0x1d
>   #define QCOM_SCM_MP_SHM_BRIDGE_CREATE		0x1e
> diff --git a/include/linux/firmware/qcom/qcom_scm.h b/include/linux/firmware/qcom/qcom_scm.h
> index 9f14976399ab..23ec8ee5e49f 100644
> --- a/include/linux/firmware/qcom/qcom_scm.h
> +++ b/include/linux/firmware/qcom/qcom_scm.h
> @@ -85,6 +85,7 @@ int qcom_scm_io_writel(phys_addr_t addr, unsigned int val);
>   
>   bool qcom_scm_restore_sec_cfg_available(void);
>   int qcom_scm_restore_sec_cfg(u32 device_id, u32 spare);
> +int qcom_scm_set_gpu_smmu_aperture(unsigned int context_bank);
>   int qcom_scm_iommu_secure_ptbl_size(u32 spare, size_t *size);
>   int qcom_scm_iommu_secure_ptbl_init(u64 addr, u32 size, u32 spare);
>   int qcom_scm_iommu_set_cp_pool_size(u32 spare, u32 size);
> 
> -- 
> 2.45.2
> 
>