[PATCH 06/15] fsi/fsi-master-gpio: Reduce turnaround clocks

From: Benjamin Herrenschmidt
Date: Mon May 28 2018 - 21:32:06 EST


FSI_GPIO_PRIME_SLAVE_CLOCKS is the number of clocks if the
"idle" phase between the end of a response and the beginning
of the next one. It corresponds to tSendDelay in the FSI
specification.

The default value in the slave is 16 clocks. 100 is way overkill
and significantly reduces the driver performance.

This changes it to 20 (which gives the HW a bit of margin still
just in case).

Signed-off-by: Benjamin Herrenschmidt <benh@xxxxxxxxxxxxxxxxxxx>
Reviewed-by: Christopher Bostic <cbostic@xxxxxxxxxxxxxxxxxx>
---
drivers/fsi/fsi-master-gpio.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/fsi/fsi-master-gpio.c b/drivers/fsi/fsi-master-gpio.c
index c82bbd35276e..029b0a5b6d89 100644
--- a/drivers/fsi/fsi-master-gpio.c
+++ b/drivers/fsi/fsi-master-gpio.c
@@ -49,7 +49,7 @@
#define FSI_GPIO_CRC_SIZE 4
#define FSI_GPIO_MSG_ID_SIZE 2
#define FSI_GPIO_MSG_RESPID_SIZE 2
-#define FSI_GPIO_PRIME_SLAVE_CLOCKS 100
+#define FSI_GPIO_PRIME_SLAVE_CLOCKS 20

struct fsi_master_gpio {
struct fsi_master master;
--
2.17.0