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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?SDjnmJ5W6vagkUUHzRlgXGIJrGYH7ApMQzkuFpkjFNkd2D8U5d3jfuZhTLnU?= =?us-ascii?Q?3GAKDBRFBYG3r/gMEz7mt2pbtgOjkSNC/9KB7Ndnd+oe1Iwaj6pIhrKs3RNs?= =?us-ascii?Q?pkP2DQol4eXgmQi6SSlqHs0c73Ct08/cQe9pnPC0weu4ZGJciTzJMmW1qPx2?= =?us-ascii?Q?YqjBRzKtMcCKoPJXiz7XF2Ehr3O0t/qmRojSn0AC2/aov+9CIIIuEQOBMAq/?= =?us-ascii?Q?esh+XMqTRnRtLCZOPSYebr6+dtwH1NAoEDwpaNoRcGhrk6p+fbCPQyf+oBor?= =?us-ascii?Q?x2xWGZOsIkc/OhEg47zn+0HTtMWEfzOMv4ECr0Ihn8ub+/e8rKweJzu5TYw9?= =?us-ascii?Q?XFaDkks9wvgRi1p47QUhgpWrmeE10oC1EbUlVt3wmJ74Dq+FW0ipqE6wOyIa?= =?us-ascii?Q?tNBSEAhMdw2tRowXpmI3dFM+dzLTQYnTI2CiQVTf1QVx3aIUWdV/gn+0utJH?= =?us-ascii?Q?F85+BOPAa1i3cPSO9umNxBnKpOiyB5WLzgYqQzz8ho6SUjHQXPzYZRAWh0dy?= =?us-ascii?Q?Fw4vXsqWXZfoLi8TWArXQLgWKjCbHvz3tYr/CHJ4w3a187G8hpsAKvaslWLD?= =?us-ascii?Q?ujUOANjx+MQWdxi8N9r7nz0Ss9CwpoaG7bw8Ifzfxkv3EwgZLWJmsFcGPvSn?= =?us-ascii?Q?AGbvboO9tDapKmFgyEHLUyLBmLQM9Z4mbR8X/l+qG8Vl9aQ83F+6NY5YCa+C?= =?us-ascii?Q?bQsE6G6SlgJomBLbLgA/XL4ZAfg010AcjJ5xEDHX89LzaqY2eCH1z6pQbsK9?= =?us-ascii?Q?/V2ve/Ddp/AKEhnOY7OYPluegOWcE3fIQZAL4jzd6aGgwJWrPOShinSivmMo?= =?us-ascii?Q?0NmN6t3+xC/MVpGcm55mWT8W4Uw+5trnSAqSxfbKCJXoO2ZH68oK2sPzMJAc?= =?us-ascii?Q?4tz7uvsRBEJnDabfaabJEuJ9hvDWfub4j337nxLuP/s40MPkpjV56OG/9pq7?= =?us-ascii?Q?1xzzYYoa59ueE3DvdYVp6xH7u87ofjC2HY88f7qZgcUrqg7ZbCfqazkkUffh?= =?us-ascii?Q?8hNxDKaMRiYvBNbQA7JLQOCHiRljr+4aRuhj5c+0D+K3krSqfDduOEwdZNp2?= =?us-ascii?Q?w3fsWLRi8egGaQPy5A3hKnG88/oBT3vS4qezHMohX6Qyj8elj1nDp35WtMFz?= =?us-ascii?Q?Hk4cWOt0KM38lMay8IAznzw0PTi8zxKdPBEFQrDNryq7+81jfTRQj8goJjyg?= =?us-ascii?Q?jli/Z0S2siAT9soy9MTjLMUEATgFhGFyJRQJVjrv4G3KogNqaYBao7vlr38m?= =?us-ascii?Q?RTBUI1scZ+fJtZxVVCBTdBS9uPqIqjylWUze1Vw4gtBvJLR3r7rFVWN+6X5c?= =?us-ascii?Q?5/D2GBtOt/wQ+g7PZf2Mc+AEusi06G9QsphtMvnFMmzox1Tt6lprKUx1n824?= =?us-ascii?Q?/RE2kv6V869UDPjmXuo10pRDl85W7k41CTQRhtfMvEf2znoc2zfIszm481rQ?= =?us-ascii?Q?FPX/k4ez/1YA9DNNVsMWqIW2nkwdy5Z+zMOG8YQmy7Bs36jY19rXZ3BI8/+3?= =?us-ascii?Q?4mWBN9RgpwO6hLIGeMTNY/uGhqdmTAJDAoxHjfQTZCXyWQ/88dnU9qo/gVaO?= =?us-ascii?Q?t6Of6aTtFO5yM7dA3+Q=3D?= X-OriginatorOrg: nxp.com X-MS-Exchange-CrossTenant-Network-Message-Id: 852ebb43-d545-4662-22e6-08de2b723bd8 X-MS-Exchange-CrossTenant-AuthSource: DU2PR04MB8951.eurprd04.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 24 Nov 2025 15:57:56.5023 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 686ea1d3-bc2b-4c6f-a92c-d99c5c301635 X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: UCvQNFlU6e83vEWq+AM4T/UuHZCh4Vhp1HUzvMcVEn25McOYYcOSh2cJ4OnEzPuQxxU4OepVK9h9tuqri0/aVg== X-MS-Exchange-Transport-CrossTenantHeadersStamped: VI1PR04MB9761 On Mon, Nov 24, 2025 at 01:50:22PM +0100, Jean-Michel Hautbois wrote: > Add dma_wmb() barrier after filling TCD descriptors to ensure all > descriptor writes are visible to the DMA engine before starting > transfers. This prevents potential race conditions where the DMA > hardware might read partially written descriptors. > > Signed-off-by: Jean-Michel Hautbois > --- > drivers/dma/fsl-edma-common.c | 3 +++ > 1 file changed, 3 insertions(+) > > diff --git a/drivers/dma/fsl-edma-common.c b/drivers/dma/fsl-edma-common.c > index 4976d7dde08090d16277af4b9f784b9745485320..db36a6aafc910364d75ce6c5d334fd19d2120b6b 100644 > --- a/drivers/dma/fsl-edma-common.c > +++ b/drivers/dma/fsl-edma-common.c > @@ -553,6 +553,9 @@ void fsl_edma_fill_tcd(struct fsl_edma_chan *fsl_chan, > fsl_edma_set_tcd_to_le(fsl_chan, tcd, csr, csr); > > trace_edma_fill_tcd(fsl_chan, tcd); > + > + /* Ensure descriptor writes are visible to DMA engine */ > + dma_wmb(); This is not necessary because there are writel() in fsl_edma_issue_pending(), which will do memory barrier in writel(). currently, edma use vchan, descriptior have not dymantically to appending to running queue. so writel() in fsl_edma_issue_pending() is enough. Even though edma will support append to running queue in future, dma_wmd() should be just before update csr. dma_wmb(); // just before indicate TCD is ready to use. fsl_edma_set_tcd_to_le(fsl_chan, tcd, csr, csr); Frank > } > > static struct fsl_edma_desc *fsl_edma_alloc_desc(struct fsl_edma_chan *fsl_chan, > > -- > 2.39.5 >