Re: [Patch v3 1/6] firmware: qcom_scm: Introduce SCM calls to access LMh

Bjorn Andersson
2021-07-10T04:02:40Z

On Thu 08 Jul 07:06 CDT 2021, Thara Gopinath wrote:

> Introduce SCM calls to access/configure limits management hardware(LMH).
>
> Signed-off-by: Thara Gopinath <thara.gopinath@linaro.org>

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

Regards,
Bjorn

> ---
>
> v2->v3:
> Added freeing of payload_buf after the scm call in qcom_scm_lmh_dcvsh as per
> Matthias review comments.
>
> v1->v2:
> Changed the input parameters in qcom_scm_lmh_dcvsh from payload_buf and
> payload_size to payload_fn, payload_reg, payload_val as per Bjorn's review
> comments.
>
> drivers/firmware/qcom_scm.c | 58 +++++++++++++++++++++++++++++++++++++
> drivers/firmware/qcom_scm.h | 4 +++
> include/linux/qcom_scm.h | 14 +++++++++
> 3 files changed, 76 insertions(+)
>
> diff --git a/drivers/firmware/qcom_scm.c b/drivers/firmware/qcom_scm.c
> index ee9cb545e73b..a8d236603e90 100644
> --- a/drivers/firmware/qcom_scm.c
> +++ b/drivers/firmware/qcom_scm.c
> @@ -1147,6 +1147,64 @@ int qcom_scm_qsmmu500_wait_safe_toggle(bool en)
> }
> EXPORT_SYMBOL(qcom_scm_qsmmu500_wait_safe_toggle);
>
> +bool qcom_scm_lmh_dcvsh_available(void)
> +{
> + return __qcom_scm_is_call_available(__scm->dev, QCOM_SCM_SVC_LMH, QCOM_SCM_LMH_LIMIT_DCVSH);
> +}
> +EXPORT_SYMBOL(qcom_scm_lmh_dcvsh_available);
> +
> +int qcom_scm_lmh_profile_change(u32 profile_id)
> +{
> + struct qcom_scm_desc desc = {
> + .svc = QCOM_SCM_SVC_LMH,
> + .cmd = QCOM_SCM_LMH_LIMIT_PROFILE_CHANGE,
> + .arginfo = QCOM_SCM_ARGS(1, QCOM_SCM_VAL),
> + .args[0] = profile_id,
> + .owner = ARM_SMCCC_OWNER_SIP,
> + };
> +
> + return qcom_scm_call(__scm->dev, &desc, NULL);
> +}
> +EXPORT_SYMBOL(qcom_scm_lmh_profile_change);
> +
> +int qcom_scm_lmh_dcvsh(u32 payload_fn, u32 payload_reg, u32 payload_val,
> + u64 limit_node, u32 node_id, u64 version)
> +{
> + dma_addr_t payload_phys;
> + u32 *payload_buf;
> + int ret, payload_size = 5 * sizeof(u32);
> +
> + struct qcom_scm_desc desc = {
> + .svc = QCOM_SCM_SVC_LMH,
> + .cmd = QCOM_SCM_LMH_LIMIT_DCVSH,
> + .arginfo = QCOM_SCM_ARGS(5, QCOM_SCM_RO, QCOM_SCM_VAL, QCOM_SCM_VAL,
> + QCOM_SCM_VAL, QCOM_SCM_VAL),
> + .args[1] = payload_size,
> + .args[2] = limit_node,
> + .args[3] = node_id,
> + .args[4] = version,
> + .owner = ARM_SMCCC_OWNER_SIP,
> + };
> +
> + payload_buf = dma_alloc_coherent(__scm->dev, payload_size, &payload_phys, GFP_KERNEL);
> + if (!payload_buf)
> + return -ENOMEM;
> +
> + payload_buf[0] = payload_fn;
> + payload_buf[1] = 0;
> + payload_buf[2] = payload_reg;
> + payload_buf[3] = 1;
> + payload_buf[4] = payload_val;
> +
> + desc.args[0] = payload_phys;
> +
> + ret = qcom_scm_call(__scm->dev, &desc, NULL);
> +
> + dma_free_coherent(__scm->dev, payload_size, payload_buf, payload_phys);
> + return ret;
> +}
> +EXPORT_SYMBOL(qcom_scm_lmh_dcvsh);
> +
> static int qcom_scm_find_dload_address(struct device *dev, u64 *addr)
> {
> struct device_node *tcsr;
> diff --git a/drivers/firmware/qcom_scm.h b/drivers/firmware/qcom_scm.h
> index 632fe3142462..d92156ceb3ac 100644
> --- a/drivers/firmware/qcom_scm.h
> +++ b/drivers/firmware/qcom_scm.h
> @@ -114,6 +114,10 @@ extern int scm_legacy_call(struct device *dev, const struct qcom_scm_desc *desc,
> #define QCOM_SCM_SVC_HDCP 0x11
> #define QCOM_SCM_HDCP_INVOKE 0x01
>
> +#define QCOM_SCM_SVC_LMH 0x13
> +#define QCOM_SCM_LMH_LIMIT_PROFILE_CHANGE 0x01
> +#define QCOM_SCM_LMH_LIMIT_DCVSH 0x10
> +
> #define QCOM_SCM_SVC_SMMU_PROGRAM 0x15
> #define QCOM_SCM_SMMU_CONFIG_ERRATA1 0x03
> #define QCOM_SCM_SMMU_CONFIG_ERRATA1_CLIENT_ALL 0x02
> diff --git a/include/linux/qcom_scm.h b/include/linux/qcom_scm.h
> index 0165824c5128..c0475d1c9885 100644
> --- a/include/linux/qcom_scm.h
> +++ b/include/linux/qcom_scm.h
> @@ -109,6 +109,12 @@ extern int qcom_scm_hdcp_req(struct qcom_scm_hdcp_req *req, u32 req_cnt,
> u32 *resp);
>
> extern int qcom_scm_qsmmu500_wait_safe_toggle(bool en);
> +
> +extern int qcom_scm_lmh_dcvsh(u32 payload_fn, u32 payload_reg, u32 payload_val,
> + u64 limit_node, u32 node_id, u64 version);
> +extern int qcom_scm_lmh_profile_change(u32 profile_id);
> +extern bool qcom_scm_lmh_dcvsh_available(void);
> +
> #else
>
> #include <linux/errno.h>
> @@ -170,5 +176,13 @@ static inline int qcom_scm_hdcp_req(struct qcom_scm_hdcp_req *req, u32 req_cnt,
>
> static inline int qcom_scm_qsmmu500_wait_safe_toggle(bool en)
> { return -ENODEV; }
> +
> +static inline int qcom_scm_lmh_dcvsh(u32 payload_fn, u32 payload_reg, u32 payload_val,
> + u64 limit_node, u32 node_id, u64 version)
> + { return -ENODEV; }
> +
> +static inline int qcom_scm_lmh_profile_change(u32 profile_id) { return -ENODEV; }
> +
> +static inline bool qcom_scm_lmh_dcvsh_available(void) { return -ENODEV; }
> #endif
> #endif
> --
> 2.25.1
>