This is a note to let you know that I've just added the patch titled
dmaengine: fsl-qdma: fix SoC may hang on 16 byte unaligned read
to the 6.6-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
dmaengine-fsl-qdma-fix-soc-may-hang-on-16-byte-unaligned-read.patch
and it can be found in the queue-6.6 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From 9d739bccf261dd93ec1babf82f5c5d71dd4caa3e Mon Sep 17 00:00:00 2001
From: Peng Ma <peng.ma@xxxxxxx>
Date: Thu, 1 Feb 2024 16:50:07 -0500
Subject: dmaengine: fsl-qdma: fix SoC may hang on 16 byte unaligned read
From: Peng Ma <peng.ma@xxxxxxx>
commit 9d739bccf261dd93ec1babf82f5c5d71dd4caa3e upstream.
There is chip (ls1028a) errata:
The SoC may hang on 16 byte unaligned read transactions by QDMA.
Unaligned read transactions initiated by QDMA may stall in the NOC
(Network On-Chip), causing a deadlock condition. Stalled transactions will
trigger completion timeouts in PCIe controller.
Workaround:
Enable prefetch by setting the source descriptor prefetchable bit
( SD[PF] = 1 ).
Implement this workaround.
Cc: stable@xxxxxxxxxxxxxxx
Fixes: b092529e0aa0 ("dmaengine: fsl-qdma: Add qDMA controller driver for Layerscape SoCs")
Signed-off-by: Peng Ma <peng.ma@xxxxxxx>
Signed-off-by: Frank Li <Frank.Li@xxxxxxx>
Link: https://lore.kernel.org/r/20240201215007.439503-1-Frank.Li@xxxxxxx
Signed-off-by: Vinod Koul <vkoul@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/dma/fsl-qdma.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)
--- a/drivers/dma/fsl-qdma.c
+++ b/drivers/dma/fsl-qdma.c
@@ -109,6 +109,7 @@
#define FSL_QDMA_CMD_WTHROTL_OFFSET 20
#define FSL_QDMA_CMD_DSEN_OFFSET 19
#define FSL_QDMA_CMD_LWC_OFFSET 16
+#define FSL_QDMA_CMD_PF BIT(17)
/* Field definition for Descriptor status */
#define QDMA_CCDF_STATUS_RTE BIT(5)
@@ -384,7 +385,8 @@ static void fsl_qdma_comp_fill_memcpy(st
qdma_csgf_set_f(csgf_dest, len);
/* Descriptor Buffer */
cmd = cpu_to_le32(FSL_QDMA_CMD_RWTTYPE <<
- FSL_QDMA_CMD_RWTTYPE_OFFSET);
+ FSL_QDMA_CMD_RWTTYPE_OFFSET) |
+ FSL_QDMA_CMD_PF;
sdf->data = QDMA_SDDF_CMD(cmd);
cmd = cpu_to_le32(FSL_QDMA_CMD_RWTTYPE <<
Patches currently in stable-queue which might be from peng.ma@xxxxxxx are
queue-6.6/dmaengine-fsl-qdma-fix-soc-may-hang-on-16-byte-unaligned-read.patch
