fpga: altera-cvp: Increase credit timeout

[ Upstream commit 0f05886 ]

Increase the timeout for SDM (Secure device manager) data credits from
20ms to 40ms. Internal stress tests running at 500 loops failed with the
current timeout of 20ms. At the start of a FPGA configuration, the CVP
host driver reads the transmit credits from SDM. It then sends bitstream
FPGA data to SDM based on the total credits. Each credit allows the
CVP host driver to send 4kBytes of data. There are situations whereby,
the SDM did not respond in time during testing.

Signed-off-by: Ang Tien Sung <tien.sung.ang@intel.com>
Signed-off-by: Kuhanh Murugasen Krishnan <kuhanh.murugasen.krishnan@intel.com>
Acked-by: Xu Yilun <yilun.xu@intel.com>
Link: https://lore.kernel.org/r/20250212221249.2715929-1-tien.sung.ang@intel.com
Signed-off-by: Xu Yilun <yilun.xu@linux.intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

drivers/fpga/altera-cvp.c

@@ -52,7 +52,7 @@
 /* V2 Defines */
 #define VSE_CVP_TX_CREDITS		0x49	/* 8bit */
 
-#define V2_CREDIT_TIMEOUT_US		20000
+#define V2_CREDIT_TIMEOUT_US		40000
 #define V2_CHECK_CREDIT_US		10
 #define V2_POLL_TIMEOUT_US		1000000
 #define V2_USER_TIMEOUT_US		500000