[PATCH 5.15 059/148] firmware: arm_scmi: Fix the asynchronous reset requests

Greg Kroah-Hartman
2022-09-26T11:19:31Z

From: Cristian Marussi <cristian.marussi@arm.com>

[ Upstream commit b75c83d9b961fd3abf7310f8d36d5e6e9f573efb ]

SCMI Reset protocol specification allows the asynchronous reset request
only when an autonomous reset action is specified. Reset requests based
on explicit assert/deassert of signals should not be served
asynchronously.

Current implementation will instead issue an asynchronous request in any
case, as long as the reset domain had advertised to support asynchronous
resets.

Avoid requesting the asynchronous resets when the reset action is not
of the autonomous type, even if the target reset domain does, in general,
support the asynchronous requests.

Link: https://lore.kernel.org/r/20220817172731.1185305-6-cristian.marussi@arm.com
Fixes: 95a15d80aa0d ("firmware: arm_scmi: Add RESET protocol in SCMI v2.0")
Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/firmware/arm_scmi/reset.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/firmware/arm_scmi/reset.c b/drivers/firmware/arm_scmi/reset.c
index fc6237d6e926..e80a78205845 100644
--- a/drivers/firmware/arm_scmi/reset.c
+++ b/drivers/firmware/arm_scmi/reset.c
@@ -158,7 +158,7 @@ static int scmi_domain_reset(const struct scmi_protocol_handle *ph, u32 domain,
return -EINVAL;

rdom = pi->dom_info + domain;
- if (rdom->async_reset)
+ if (rdom->async_reset && flags & AUTONOMOUS_RESET)
flags |= ASYNCHRONOUS_RESET;

ret = ph->xops->xfer_get_init(ph, RESET, sizeof(*dom), 0, &t);
@@ -170,7 +170,7 @@ static int scmi_domain_reset(const struct scmi_protocol_handle *ph, u32 domain,
dom->flags = cpu_to_le32(flags);
dom->reset_state = cpu_to_le32(state);

- if (rdom->async_reset)
+ if (flags & ASYNCHRONOUS_RESET)
ret = ph->xops->do_xfer_with_response(ph, t);
else
ret = ph->xops->do_xfer(ph, t);
--
2.35.1