dmaengine: fsl-qdma: fix SoC may hang on 16 byte unaligned read

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: [email protected]
Fixes: b092529e0a ("dmaengine: fsl-qdma: Add qDMA controller driver for Layerscape SoCs")
Signed-off-by: Peng Ma <[email protected]>
Signed-off-by: Frank Li <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Vinod Koul <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
This commit is contained in:
Peng Ma 2024-02-01 16:50:07 -05:00 • committed by Greg Kroah-Hartman
commit 518d78b4fa

View file

@ -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 offset */
#define QDMA_CCDF_STATUS 20
@ -372,7 +373,8 @@ static void fsl_qdma_comp_fill_memcpy(struct fsl_qdma_comp *fsl_comp,
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 <<