[PATCH v7 09/16] firmware: arm_scmi: Make smc support atomic sync commands replies

Cristian Marussi
2021-11-29T19:16:41Z

Enable sync_cmds_atomic_replies in the SMC transport descriptor and remove
SMC specific .poll_done callback support since polling is bypassed when
sync_cmds_atomic_replies is set.

Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
---
v4 --> v5
- removed RFC tag
- added comment on setting flag
- remove smc_poll_done
---
drivers/firmware/arm_scmi/smc.c | 18 +++++++++---------
1 file changed, 9 insertions(+), 9 deletions(-)

diff --git a/drivers/firmware/arm_scmi/smc.c b/drivers/firmware/arm_scmi/smc.c
index d6c6ad9f6bab..b2f31d3feb10 100644
--- a/drivers/firmware/arm_scmi/smc.c
+++ b/drivers/firmware/arm_scmi/smc.c
@@ -173,14 +173,6 @@ static void smc_mark_txdone(struct scmi_chan_info *cinfo, int ret)
mutex_unlock(&scmi_info->shmem_lock);
}

-static bool
-smc_poll_done(struct scmi_chan_info *cinfo, struct scmi_xfer *xfer)
-{
- struct scmi_smc *scmi_info = cinfo->transport_info;
-
- return shmem_poll_done(scmi_info->shmem, xfer);
-}
-
static const struct scmi_transport_ops scmi_smc_ops = {
.chan_available = smc_chan_available,
.chan_setup = smc_chan_setup,
@@ -188,7 +180,6 @@ static const struct scmi_transport_ops scmi_smc_ops = {
.send_message = smc_send_message,
.mark_txdone = smc_mark_txdone,
.fetch_response = smc_fetch_response,
- .poll_done = smc_poll_done,
};

const struct scmi_desc scmi_smc_desc = {
@@ -196,4 +187,13 @@ const struct scmi_desc scmi_smc_desc = {
.max_rx_timeout_ms = 30,
.max_msg = 20,
.max_msg_size = 128,
+ /*
+ * Setting .sync_cmds_atomic_replies to true for SMC assumes that,
+ * once the SMC instruction has completed successfully, the issued
+ * SCMI command would have been already fully processed by the SCMI
+ * platform firmware and so any possible response value expected
+ * for the issued command will be immmediately ready to be fetched
+ * from the shared memory area.
+ */
+ .sync_cmds_atomic_replies = true,
};
--
2.17.1