Re: [PATCH v2 10/11] firmware: qcom-scm: add support for SHM bridge operations

From: Elliot Berman
Date: Thu Sep 28 2023 - 13:10:16 EST



On 9/28/2023 2:20 AM, Bartosz Golaszewski wrote:
> From: Bartosz Golaszewski <bartosz.golaszewski@xxxxxxxxxx>
>
> Add low-level primitives for enabling SHM bridge support, creating SHM
> bridge pools and testing the availability of SHM bridges to qcom-scm. We
> don't yet provide a way to destroy the bridges as the first user will
> not require it.
>
> Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@xxxxxxxxxx>

After fixing the typo:

Reviewed-by: Elliot Berman <quic_eberman@xxxxxxxxxxx>

> ---
> drivers/firmware/qcom/qcom_scm.c | 43 ++++++++++++++++++++++++++
> drivers/firmware/qcom/qcom_scm.h | 2 ++
> include/linux/firmware/qcom/qcom_scm.h | 6 ++++
> 3 files changed, 51 insertions(+)
>
> diff --git a/drivers/firmware/qcom/qcom_scm.c b/drivers/firmware/qcom/qcom_scm.c
> index 1fa27c44f472..5969ff0c0beb 100644
> --- a/drivers/firmware/qcom/qcom_scm.c
> +++ b/drivers/firmware/qcom/qcom_scm.c
> @@ -1296,6 +1296,49 @@ bool qcom_scm_lmh_dcvsh_available(void)
> }
> EXPORT_SYMBOL_GPL(qcom_scm_lmh_dcvsh_available);
>
> +int qcom_scm_enable_shm_bridge(void)
> +{
> + struct qcom_scm_desc desc = {
> + .svc = QCOM_SCM_SVC_MP,
> + .cmd = QCOM_SCM_MP_SHM_BRIDGE_ENABLE,
> + .owner = ARM_SMCCC_OWNER_SIP
> + };
> +
> + struct qcom_scm_res res;
> +
> + if (!__qcom_scm_is_call_available(__scm->dev, QCOM_SCM_SVC_MP,
> + QCOM_SCM_MP_SHM_BRIDGE_ENABLE))
> + return -EOPNOTSUPP;
> +
> + return qcom_scm_call(__scm->dev, &desc, &res) ?: res.result[0];
> +}
> +EXPORT_SYMBOL_GPL(qcom_scm_enable_shm_bridge);
> +
> +int qcom_scm_create_shm_bridge(struct device *dev, u64 pfn_and_ns_perm_flags,
> + u64 ipfn_and_s_perm_flags, u64 size_and_flags,
> + u64 ns_vmids)
> +{
> + struct qcom_scm_desc desc = {
> + .svc = QCOM_SCM_SVC_MP,
> + .cmd = QCOM_SCM_MP_SHM_BRDIGE_CREATE,

s/BRDIGE/BRIDGE/g

> + .owner = ARM_SMCCC_OWNER_SIP,
> + .args[0] = pfn_and_ns_perm_flags,
> + .args[1] = ipfn_and_s_perm_flags,
> + .args[2] = size_and_flags,
> + .args[3] = ns_vmids,
> + .arginfo = QCOM_SCM_ARGS(4, QCOM_SCM_VAL, QCOM_SCM_VAL,
> + QCOM_SCM_VAL, QCOM_SCM_VAL),
> + };
> +
> + struct qcom_scm_res res;
> + int ret;
> +
> + ret = qcom_scm_call(__scm->dev, &desc, &res);
> +
> + return ret ?: res.result[0];
> +}
> +EXPORT_SYMBOL_GPL(qcom_scm_create_shm_bridge);
> +
> int qcom_scm_lmh_profile_change(u32 profile_id)
> {
> struct qcom_scm_desc desc = {
> diff --git a/drivers/firmware/qcom/qcom_scm.h b/drivers/firmware/qcom/qcom_scm.h
> index 8c97e3906afa..f5a29bc0f549 100644
> --- a/drivers/firmware/qcom/qcom_scm.h
> +++ b/drivers/firmware/qcom/qcom_scm.h
> @@ -116,6 +116,8 @@ extern int scm_legacy_call(struct device *dev, const struct qcom_scm_desc *desc,
> #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_SHM_BRIDGE_ENABLE 0x1c
> +#define QCOM_SCM_MP_SHM_BRDIGE_CREATE 0x1e

s/BRDIGE/BRIDGE/g

>
> #define QCOM_SCM_SVC_OCMEM 0x0f
> #define QCOM_SCM_OCMEM_LOCK_CMD 0x01
> diff --git a/include/linux/firmware/qcom/qcom_scm.h b/include/linux/firmware/qcom/qcom_scm.h
> index 291ef8fd21b0..dc26cfd6d011 100644
> --- a/include/linux/firmware/qcom/qcom_scm.h
> +++ b/include/linux/firmware/qcom/qcom_scm.h
> @@ -6,6 +6,7 @@
> #define __QCOM_SCM_H
>
> #include <linux/cleanup.h>
> +#include <linux/device.h>
> #include <linux/err.h>
> #include <linux/gfp.h>
> #include <linux/types.h>
> @@ -122,6 +123,11 @@ int qcom_scm_lmh_dcvsh(u32 payload_fn, u32 payload_reg, u32 payload_val,
> int qcom_scm_lmh_profile_change(u32 profile_id);
> bool qcom_scm_lmh_dcvsh_available(void);
>
> +int qcom_scm_enable_shm_bridge(void);
> +int qcom_scm_create_shm_bridge(struct device *dev, u64 pfn_and_ns_perm_flags,
> + u64 ipfn_and_s_perm_flags, u64 size_and_flags,
> + u64 ns_vmids);
> +
> #ifdef CONFIG_QCOM_QSEECOM
>
> int qcom_scm_qseecom_app_get_id(const char *app_name, u32 *app_id);