[PATCH] spi: spi-cadence-qspi: Disable STIG mode for Altera SoCFPGA.

[PATCH] spi: spi-cadence-qspi: Disable STIG mode for Altera SoCFPGA.

[niravkumar.l.rabara]

From: Niravkumar L Rabara <niravkumar.l.rabara@intel.com>

STIG mode is enabled by default for less than 8 bytes data read/write.
STIG mode doesn't work with Altera SocFPGA platform due hardware
limitation.
Add a quirks to disable STIG mode for Altera SoCFPGA platform.

Signed-off-by: Niravkumar L Rabara <niravkumar.l.rabara@intel.com>
---
 drivers/spi/spi-cadence-quadspi.c | 10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/drivers/spi/spi-cadence-quadspi.c b/drivers/spi/spi-cadence-quadspi.c
index 0b45b7b2b3ab..a031ecb358e0 100644
--- a/drivers/spi/spi-cadence-quadspi.c
+++ b/drivers/spi/spi-cadence-quadspi.c
@@ -43,6 +43,7 @@ static_assert(CQSPI_MAX_CHIPSELECT <= SPI_CS_CNT_MAX);
 #define CQSPI_SLOW_SRAM		BIT(4)
 #define CQSPI_NEEDS_APB_AHB_HAZARD_WAR	BIT(5)
 #define CQSPI_RD_NO_IRQ			BIT(6)
+#define CQSPI_DISABLE_STIG_MODE		BIT(7)
 
 /* Capabilities */
 #define CQSPI_SUPPORTS_OCTAL		BIT(0)
@@ -103,6 +104,7 @@ struct cqspi_st {
 	bool			apb_ahb_hazard;
 
 	bool			is_jh7110; /* Flag for StarFive JH7110 SoC */
+	bool			disable_stig_mode;
 
 	const struct cqspi_driver_platdata *ddata;
 };
@@ -1416,7 +1418,8 @@ static int cqspi_mem_process(struct spi_mem *mem, const struct spi_mem_op *op)
 	 * reads, prefer STIG mode for such small reads.
 	 */
 		if (!op->addr.nbytes ||
-		    op->data.nbytes <= CQSPI_STIG_DATA_LEN_MAX)
+		    (op->data.nbytes <= CQSPI_STIG_DATA_LEN_MAX &&
+		     !cqspi->disable_stig_mode))
 			return cqspi_command_read(f_pdata, op);
 
 		return cqspi_read(f_pdata, op);
@@ -1880,6 +1883,8 @@ static int cqspi_probe(struct platform_device *pdev)
 			if (ret)
 				goto probe_reset_failed;
 		}
+		if (ddata->quirks & CQSPI_DISABLE_STIG_MODE)
+			cqspi->disable_stig_mode = true;
 
 		if (of_device_is_compatible(pdev->dev.of_node,
 					    "xlnx,versal-ospi-1.0")) {
@@ -2043,7 +2048,8 @@ static const struct cqspi_driver_platdata intel_lgm_qspi = {
 static const struct cqspi_driver_platdata socfpga_qspi = {
 	.quirks = CQSPI_DISABLE_DAC_MODE
 			| CQSPI_NO_SUPPORT_WR_COMPLETION
-			| CQSPI_SLOW_SRAM,
+			| CQSPI_SLOW_SRAM
+			| CQSPI_DISABLE_STIG_MODE,
 };
 
 static const struct cqspi_driver_platdata versal_ospi = {
-- 
2.25.1

Re: [PATCH] spi: spi-cadence-qspi: Disable STIG mode for Altera SoCFPGA.

[Mark Brown]

On Wed, 04 Dec 2024 14:33:38 +0800, niravkumar.l.rabara@intel.com wrote:
> STIG mode is enabled by default for less than 8 bytes data read/write.
> STIG mode doesn't work with Altera SocFPGA platform due hardware
> limitation.
> Add a quirks to disable STIG mode for Altera SoCFPGA platform.
> 
> 

Applied to

   https://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi.git for-next

Thanks!

[1/1] spi: spi-cadence-qspi: Disable STIG mode for Altera SoCFPGA.
      commit: 25fb0e77b90e290a1ca30900d54c6a495eea65e2

All being well this means that it will be integrated into the linux-next
tree (usually sometime in the next 24 hours) and sent to Linus during
the next merge window (or sooner if it is a bug fix), however if
problems are discovered then the patch may be dropped or reverted.

You may get further e-mails resulting from automated or manual testing
and review of the tree, please engage with people reporting problems and
send followup patches addressing any issues that are reported if needed.

If any updates are required or you are submitting further changes they
should be sent as incremental updates against current git, existing
patches will not be replaced.

Please add any relevant lists and maintainers to the CCs when replying
to this mail.

Thanks,
Mark