[PATCH] spi: zynqmp-gqspi: Scale timeout by data size

[PATCH] spi: zynqmp-gqspi: Scale timeout by data size

[Sean Anderson]

Large blocks of data time out when reading because we don't wait long
enough for the transfer to complete. Scale our timeouts based on the
amount of data we are tranferring, with a healthy dose of pessimism.

Signed-off-by: Sean Anderson <sean.anderson@linux.dev>
---

 drivers/spi/spi-zynqmp-gqspi.c | 30 ++++++++++++++++++++++++------
 1 file changed, 24 insertions(+), 6 deletions(-)

diff --git a/drivers/spi/spi-zynqmp-gqspi.c b/drivers/spi/spi-zynqmp-gqspi.c
index 99524a3c9f38..558c466135a5 100644
--- a/drivers/spi/spi-zynqmp-gqspi.c
+++ b/drivers/spi/spi-zynqmp-gqspi.c
@@ -1033,6 +1033,18 @@ static int __maybe_unused zynqmp_runtime_resume(struct device *dev)
 	return 0;
 }
 
+static unsigned long zynqmp_qspi_timeout(struct zynqmp_qspi *xqspi, u8 bits,
+					 unsigned long bytes)
+{
+	unsigned long timeout;
+
+	/* Assume we are at most 2x slower than the nominal bus speed */
+	timeout = mult_frac(bytes, 2 * 8 * MSEC_PER_SEC,
+			    bits * xqspi->speed_hz);
+	/* And add 100 ms for scheduling delays */
+	return msecs_to_jiffies(timeout + 100);
+}
+
 /**
  * zynqmp_qspi_exec_op() - Initiates the QSPI transfer
  * @mem: The SPI memory
@@ -1049,6 +1061,7 @@ static int zynqmp_qspi_exec_op(struct spi_mem *mem,
 {
 	struct zynqmp_qspi *xqspi = spi_controller_get_devdata
 				    (mem->spi->controller);
+	unsigned long timeout;
 	int err = 0, i;
 	u32 genfifoentry = 0;
 	u16 opcode = op->cmd.opcode;
@@ -1077,8 +1090,10 @@ static int zynqmp_qspi_exec_op(struct spi_mem *mem,
 		zynqmp_gqspi_write(xqspi, GQSPI_IER_OFST,
 				   GQSPI_IER_GENFIFOEMPTY_MASK |
 				   GQSPI_IER_TXNOT_FULL_MASK);
-		if (!wait_for_completion_timeout
-		    (&xqspi->data_completion, msecs_to_jiffies(1000))) {
+		timeout = zynqmp_qspi_timeout(xqspi, op->cmd.buswidth,
+					      op->cmd.nbytes);
+		if (!wait_for_completion_timeout(&xqspi->data_completion,
+						 timeout)) {
 			err = -ETIMEDOUT;
 			goto return_err;
 		}
@@ -1104,8 +1119,10 @@ static int zynqmp_qspi_exec_op(struct spi_mem *mem,
 				   GQSPI_IER_TXEMPTY_MASK |
 				   GQSPI_IER_GENFIFOEMPTY_MASK |
 				   GQSPI_IER_TXNOT_FULL_MASK);
-		if (!wait_for_completion_timeout
-		    (&xqspi->data_completion, msecs_to_jiffies(1000))) {
+		timeout = zynqmp_qspi_timeout(xqspi, op->addr.buswidth,
+					      op->addr.nbytes);
+		if (!wait_for_completion_timeout(&xqspi->data_completion,
+						 timeout)) {
 			err = -ETIMEDOUT;
 			goto return_err;
 		}
@@ -1173,8 +1190,9 @@ static int zynqmp_qspi_exec_op(struct spi_mem *mem,
 						   GQSPI_IER_RXEMPTY_MASK);
 			}
 		}
-		if (!wait_for_completion_timeout
-		    (&xqspi->data_completion, msecs_to_jiffies(1000)))
+		timeout = zynqmp_qspi_timeout(xqspi, op->data.buswidth,
+					      op->data.nbytes);
+		if (!wait_for_completion_timeout(&xqspi->data_completion, timeout))
 			err = -ETIMEDOUT;
 	}
 
-- 
2.35.1.1320.gc452695387.dirty

Re: [PATCH] spi: zynqmp-gqspi: Scale timeout by data size

[Mark Brown]

On Fri, 09 Aug 2024 16:15:39 -0400, Sean Anderson wrote:
> Large blocks of data time out when reading because we don't wait long
> enough for the transfer to complete. Scale our timeouts based on the
> amount of data we are tranferring, with a healthy dose of pessimism.
> 
> 

Applied to

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

Thanks!

[1/1] spi: zynqmp-gqspi: Scale timeout by data size
      commit: 5d61841c74db8b5bbbf9403f1bd4879f614617d2

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