[PATCH 5.4 082/102] firmware: arm_scmi: Fix doorbell ring logic for !CONFIG_64BIT

Greg Kroah-Hartman
2020-01-24T09:42:13Z

From: Sudeep Holla <sudeep.holla@arm.com>

[ Upstream commit 7bd39bc6bfdf96f5df0f92199bbc1a3ee2f2adb8 ]

The logic to ring the scmi performance fastchannel ignores the
value read from the doorbell register in case of !CONFIG_64BIT.
This bug also shows up as warning with '-Wunused-but-set-variable' gcc
flag:

drivers/firmware/arm_scmi/perf.c: In function scmi_perf_fc_ring_db:
drivers/firmware/arm_scmi/perf.c:323:7: warning: variable val set but
not used [-Wunused-but-set-variable]

Fix the same by aligning the logic with CONFIG_64BIT as used in the
macro SCMI_PERF_FC_RING_DB().

Fixes: 823839571d76 ("firmware: arm_scmi: Make use SCMI v2.0 fastchannel for performance protocol")
Reported-by: Hulk Robot <hulkci@huawei.com>
Reported-by: Zheng Yongjun <zhengyongjun3@huawei.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/firmware/arm_scmi/perf.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/firmware/arm_scmi/perf.c b/drivers/firmware/arm_scmi/perf.c
index 4a8012e3cb8c3..601af4edad5e6 100644
--- a/drivers/firmware/arm_scmi/perf.c
+++ b/drivers/firmware/arm_scmi/perf.c
@@ -323,7 +323,7 @@ static void scmi_perf_fc_ring_db(struct scmi_fc_db_info *db)

if (db->mask)
val = ioread64_hi_lo(db->addr) & db->mask;
- iowrite64_hi_lo(db->set, db->addr);
+ iowrite64_hi_lo(db->set | val, db->addr);
}
#endif
}
--
2.20.1