fsi/sbefifo: Fix reset timeout

[ Upstream commit 9ab1428 ]

On BMCs with lower timer resolution than 1ms, msleep(1) will take
way longer than 1ms, so looping 10k times won't wait for 10s but
significantly longer.

Fix this by using jiffies like the rest of the code.

Fixes: 9f4a8a2 ("fsi/sbefifo: Add driver for the SBE FIFO")
Signed-off-by: Joachim Fenkes <fenkes@de.ibm.com>
Link: https://lore.kernel.org/r/20200724071518.430515-3-joel@jms.id.au
Signed-off-by: Joel Stanley <joel@jms.id.au>
Signed-off-by: Sasha Levin <sashal@kernel.org>

drivers/fsi/fsi-sbefifo.c

@@ -325,7 +325,8 @@ static int sbefifo_up_write(struct sbefifo *sbefifo, __be32 word)
 static int sbefifo_request_reset(struct sbefifo *sbefifo)
 {
 	struct device *dev = &sbefifo->fsi_dev->dev;
-	u32 status, timeout;
+	unsigned long end_time;
+	u32 status;
 	int rc;
 
 	dev_dbg(dev, "Requesting FIFO reset\n");
@@ -341,7 +342,8 @@ static int sbefifo_request_reset(struct sbefifo *sbefifo)
 	}
 
 	/* Wait for it to complete */
-	for (timeout = 0; timeout < SBEFIFO_RESET_TIMEOUT; timeout++) {
+	end_time = jiffies + msecs_to_jiffies(SBEFIFO_RESET_TIMEOUT);
+	while (!time_after(jiffies, end_time)) {
 		rc = sbefifo_regr(sbefifo, SBEFIFO_UP | SBEFIFO_STS, &status);
 		if (rc) {
 			dev_err(dev, "Failed to read UP fifo status during reset"
@@ -355,7 +357,7 @@ static int sbefifo_request_reset(struct sbefifo *sbefifo)
 			return 0;
 		}
 
-		msleep(1);
+		cond_resched();
 	}
 	dev_err(dev, "FIFO reset timed out\n");