diff mbox series

[v5,4/4] firmware: arm_scmi: optee: use optee system invocation

Message ID 20230320162801.2811542-4-etienne.carriere@linaro.org (mailing list archive)
State New, archived
Headers show
Series [v5,1/4] tee: optee: system call property | expand

Commit Message

Etienne Carriere March 20, 2023, 4:28 p.m. UTC
Changes SCMI optee transport to call tee_client_system_session()
to request optee driver to provision an entry context in OP-TEE
for processing OP-TEE messages. This prevents possible deadlock
in case OP-TEE threads are all consumed while these may be waiting
for a clock or regulator to be enable which SCMI OP-TEE service which
requires a free thread context to execute.

Signed-off-by: Etienne Carriere <etienne.carriere@linaro.org>
---
Changes since v4:
- Updated to new API function tee_client_system_session() introduced
  in patch v5 2/3.

No change since v3

Changes since v2:
- Fixed syntax issues (missing ';' chars), reported by kernel test robot.

Changes since v1:
- Updated to use new tee API functions tee_client_request_system_context()
  and tee_client_release_system_context().
---
 drivers/firmware/arm_scmi/optee.c | 4 ++++
 1 file changed, 4 insertions(+)

Comments

Sudeep Holla March 22, 2023, 4:40 p.m. UTC | #1
On Mon, Mar 20, 2023 at 05:28:01PM +0100, Etienne Carriere wrote:
> Changes SCMI optee transport to call tee_client_system_session()
> to request optee driver to provision an entry context in OP-TEE
> for processing OP-TEE messages. This prevents possible deadlock
> in case OP-TEE threads are all consumed while these may be waiting
> for a clock or regulator to be enable which SCMI OP-TEE service which
> requires a free thread context to execute.
>

Assuming it will be routed via OPTEE tree,

Acked-by: Sudeep Holla <sudeep.holla@arm.com>
diff mbox series

Patch

diff --git a/drivers/firmware/arm_scmi/optee.c b/drivers/firmware/arm_scmi/optee.c
index 2a7aeab40e54..22a755160c2f 100644
--- a/drivers/firmware/arm_scmi/optee.c
+++ b/drivers/firmware/arm_scmi/optee.c
@@ -440,6 +440,10 @@  static int scmi_optee_chan_setup(struct scmi_chan_info *cinfo, struct device *de
 	if (ret)
 		goto err_free_shm;
 
+	ret = tee_client_system_session(scmi_optee_private->tee_ctx, channel->tee_session);
+	if (ret)
+		dev_warn(dev, "Could not switch to system session, do best effort\n");
+
 	ret = get_channel(channel);
 	if (ret)
 		goto err_close_sess;