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>
---
drivers/firmware/qcom_scm.c | 83 ++++++++++++++++++++++++++
drivers/firmware/qcom_scm.h | 3 +
include/linux/firmware/qcom/qcom_scm.h | 8 +++
3 files changed, 94 insertions(+)
diff --git a/drivers/firmware/qcom_scm.c b/drivers/firmware/qcom_scm.c
index 422de70faff8..f45d5a424424 100644
--- a/drivers/firmware/qcom_scm.c
+++ b/drivers/firmware/qcom_scm.c
@@ -31,6 +31,8 @@ module_param(download_mode, bool, 0);
#define SCM_HAS_IFACE_CLK BIT(1)
#define SCM_HAS_BUS_CLK BIT(2)
+#define SCM_SHM_BRIDGE_NOTSUPP 4
+
struct qcom_scm {
struct device *dev;
struct clk *core_clk;
@@ -45,6 +47,8 @@ struct qcom_scm {
int scm_vote_count;
u64 dload_mode_addr;
+
+ bool shm_bridge_enabled;
};
struct qcom_scm_current_perm_info {
@@ -1248,6 +1252,85 @@ bool qcom_scm_lmh_dcvsh_available(void)
}
EXPORT_SYMBOL(qcom_scm_lmh_dcvsh_available);
+bool qcom_scm_shm_bridge_available(void)
+{
+ if (!qcom_scm_is_available())
+ return false;
+
+ return READ_ONCE(__scm->shm_bridge_enabled);
+}
+EXPORT_SYMBOL_GPL(qcom_scm_shm_bridge_available);
+
+/*
+ * Must not be called unless qcom_scm_shm_bridge_available() returned true
+ * first.
+ */
+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;
+ int ret;
+
+ ret = qcom_scm_call(__scm->dev, &desc, &res);
+ if (!ret && !res.result[0])
+ WRITE_ONCE(__scm->shm_bridge_enabled, true);
+
+ if (res.result[0] == SCM_SHM_BRIDGE_NOTSUPP)
+ ret = -EOPNOTSUPP;
+
+ return ret ?: 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, u64 *handle)
+{
+ struct qcom_scm_desc desc = {
+ .svc = QCOM_SCM_SVC_MP,
+ .cmd = QCOM_SCM_MP_SHM_BRDIGE_CREATE,
+ .owner = ARM_SMCCC_OWNER_SIP
+ };
+
+ struct qcom_scm_res res;
+ int ret;
+
+ desc.args[0] = pfn_and_ns_perm_flags;
+ desc.args[1] = ipfn_and_s_perm_flags;
+ desc.args[2] = size_and_flags;
+ desc.args[3] = ns_vmids;
+
+ desc.arginfo = QCOM_SCM_ARGS(4, QCOM_SCM_VAL, QCOM_SCM_VAL,
+ QCOM_SCM_VAL, QCOM_SCM_VAL);
+
+ ret = qcom_scm_call(dev ?: __scm->dev, &desc, &res);
+
+ if (handle && !ret)
+ *handle = res.result[1];
+
+ return ret ?: res.result[0];
+}
+EXPORT_SYMBOL_GPL(qcom_scm_create_shm_bridge);
+
+int qcom_scm_delete_shm_bridge(struct device *dev, u64 handle)
+{
+ struct qcom_scm_desc desc = {
+ .svc = QCOM_SCM_SVC_MP,
+ .cmd = QCOM_SCM_MP_SHM_BRIDGE_DELETE,
+ .owner = ARM_SMCCC_OWNER_SIP,
+ .args[0] = handle,
+ .arginfo = QCOM_SCM_ARGS(1, QCOM_SCM_VAL),
+ };
+
+ return qcom_scm_call(dev ?: __scm->dev, &desc, NULL);
+}
+EXPORT_SYMBOL_GPL(qcom_scm_delete_shm_bridge);
+
int qcom_scm_lmh_profile_change(u32 profile_id)
{
struct qcom_scm_desc desc = {
diff --git a/drivers/firmware/qcom_scm.h b/drivers/firmware/qcom_scm.h
index e6e512bd57d1..44d60d06344b 100644
--- a/drivers/firmware/qcom_scm.h
+++ b/drivers/firmware/qcom_scm.h
@@ -111,6 +111,9 @@ 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_BRIDGE_DELETE 0x1d
+#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 0187fc54249e..100770380d97 100644
--- a/include/linux/firmware/qcom/qcom_scm.h
+++ b/include/linux/firmware/qcom/qcom_scm.h
@@ -5,6 +5,7 @@
#ifndef __QCOM_SCM_H
#define __QCOM_SCM_H
+#include <linux/device.h>
#include <linux/err.h>
#include <linux/types.h>
#include <linux/cpumask.h>
@@ -117,4 +118,11 @@ 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);
+bool qcom_scm_shm_bridge_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, u64 *handle);
+int qcom_scm_delete_shm_bridge(struct device *dev, u64 handle);
+
#endif
--
2.39.2
