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

Bartosz Golaszewski
2023-09-28T09:21:54Z

From: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>

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@linaro.org>
---
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,
+ .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

#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);
--
2.39.2