[PATCH 4.19 192/421] fsi: scom: Reset the FSI2PIB engine for any error

Greg Kroah-Hartman
2021-07-19T16:17:52Z

From: Eddie James <eajames@linux.ibm.com>

[ Upstream commit a5c317dac5567206ca7b6bc9d008dd6890c8bced ]

The error bits in the FSI2PIB status are only cleared by a reset. So
the driver needs to perform a reset after seeing any of the FSI2PIB
errors, otherwise subsequent operations will also look like failures.

Fixes: 6b293258cded ("fsi: scom: Major overhaul")
Signed-off-by: Eddie James <eajames@linux.ibm.com>
Reviewed-by: Joel Stanley <joel@jms.id.au>
Link: https://lore.kernel.org/r/20210329151344.14246-1-eajames@linux.ibm.com
Signed-off-by: Joel Stanley <joel@jms.id.au>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/fsi/fsi-scom.c | 16 +++++++++-------
1 file changed, 9 insertions(+), 7 deletions(-)

diff --git a/drivers/fsi/fsi-scom.c b/drivers/fsi/fsi-scom.c
index fdc0e458dbaa..6a48b3144410 100644
--- a/drivers/fsi/fsi-scom.c
+++ b/drivers/fsi/fsi-scom.c
@@ -47,9 +47,10 @@
#define SCOM_STATUS_PIB_RESP_MASK 0x00007000
#define SCOM_STATUS_PIB_RESP_SHIFT 12

-#define SCOM_STATUS_ANY_ERR (SCOM_STATUS_PROTECTION | \
- SCOM_STATUS_PARITY | \
- SCOM_STATUS_PIB_ABORT | \
+#define SCOM_STATUS_FSI2PIB_ERROR (SCOM_STATUS_PROTECTION | \
+ SCOM_STATUS_PARITY | \
+ SCOM_STATUS_PIB_ABORT)
+#define SCOM_STATUS_ANY_ERR (SCOM_STATUS_FSI2PIB_ERROR | \
SCOM_STATUS_PIB_RESP_MASK)
/* SCOM address encodings */
#define XSCOM_ADDR_IND_FLAG BIT_ULL(63)
@@ -249,13 +250,14 @@ static int handle_fsi2pib_status(struct scom_device *scom, uint32_t status)
{
uint32_t dummy = -1;

- if (status & SCOM_STATUS_PROTECTION)
- return -EPERM;
- if (status & SCOM_STATUS_PARITY) {
+ if (status & SCOM_STATUS_FSI2PIB_ERROR)
fsi_device_write(scom->fsi_dev, SCOM_FSI2PIB_RESET_REG, &dummy,
sizeof(uint32_t));
+
+ if (status & SCOM_STATUS_PROTECTION)
+ return -EPERM;
+ if (status & SCOM_STATUS_PARITY)
return -EIO;
- }
/* Return -EBUSY on PIB abort to force a retry */
if (status & SCOM_STATUS_PIB_ABORT)
return -EBUSY;
--
2.30.2