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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?3qMLaYJ7p2PyDQcJc1jggsy19Nrcyf8Vg0yYe+9D5cuF9UN5NgsBlU1e+bGE?= =?us-ascii?Q?eo6q1llsDnuY9qAUvu88ipPmytkdwnG9emTl3lBY1lgAhMf+EVHTCWgHFndK?= =?us-ascii?Q?cYEIH+T1eVqGF1oZNUSC09iOvVONBSwjvSZ5W3iJxNwzIqGHc9W4B6b6g2jI?= =?us-ascii?Q?axAOZMD7/sE1JfmZ/P7UTjOWFBj1Tu+wkcsZGGnGf8cHFcLtVVkeTEDGVegX?= =?us-ascii?Q?oAPkfGj9vZsyXB1QPBQkBLXXeCp7KUfpSvqnt4His6DfxqMSHclOaBOLd0av?= =?us-ascii?Q?I+D+i/xIv8cPpRtfXAPOqT+DLQGwOe6H86NBAvUEAgmmV2NszYUry856XxYE?= =?us-ascii?Q?sslsMfQD0ebL8DSjZoHAdUg5wlURw0aGZ7jfIcl2QQD5vgu9Vk/YeWOtBvZV?= =?us-ascii?Q?OTaQEYJBdDaCm339z31q9d6GdTpP40iLd4P1O75V1aOStHS/fNzo77ZHlAV/?= =?us-ascii?Q?iLqHgxMYF3A3l7fpelicde6A895whF77wjmCS9m/K7eOPIaIqh/lEUD9D0oA?= =?us-ascii?Q?Z3HW8Iqo76P82EHT7GquTnYZrPrutLU/hmzaKN0glcI+KHcRuh7dFFTp/97E?= =?us-ascii?Q?Jh4lLBH6m8zffINP1JqiJTyCftO9x93uj477/aw/8KSDLJJGmWX96NN++3VG?= =?us-ascii?Q?9/yeFf5wTM7yh8o2CEiGuJ/Zkdza2WrgR1KzD92OHYVEFMuMSZb0uvz10fRi?= =?us-ascii?Q?DMd1uJ/mO9TiZoNdOlsjC6pAfE0IdRQVXSIbru+QOIKl2LNN2zgWuRnW3uT9?= =?us-ascii?Q?RGw9g+nORzjdHKCZlnqpUqGFOw3X2eNgt1f4FYBus5Tpkf/E6k4CX+AVJeIm?= =?us-ascii?Q?fqPM1uRJpZ5fUjv3UCVn1hw5ASMEWY4S83KC5i92lsBWyltXQciQFJlQmZzh?= =?us-ascii?Q?QkFA4LbUvNTj3/wkHzbduqAd/xgYmaHot2FdjGtBoaWaBAU9EyGh4jsMf+jg?= =?us-ascii?Q?09JSdzvr0IzIZ43q60C+kWTnWSMoGNQZ7c9CuA3MWhBTIwWn+vhcFtFwKbKV?= =?us-ascii?Q?eXarY0TqZodVQgEBkcG+hl7qDsmbJ6G1dLJkLy7OqhJ6z22cV6TRyO+CBP4W?= =?us-ascii?Q?ateM9bQlCu9oZqxB/i4lY5YaweAkcpjauN+IAnSbjsGjlJGeCsWg9LDG/Tyn?= =?us-ascii?Q?vzkg1VKQpysemsTuhkdMCNjgi8gEfIocYwHUFXjygXMA+gBIvJnvGATSyjpl?= =?us-ascii?Q?dv+KFTzb6XYbW416fGRki14Uf6WyKwkeVYXt4A10XCEEDOfHvy303wDxfRpj?= =?us-ascii?Q?1s11hfBqC1rE1h2KlcrUv6k9eHxKQgUp2aAyX6RrLGIbyco2K4fIR9P0ao/R?= =?us-ascii?Q?98DeCE9oLDfSsZmXw2MOo2HbKOpYI5ngsttr8QNR4BqOhsdNYleUTbmLQtcw?= =?us-ascii?Q?m7wqL48QagslYWxQEYL8hWxxZQL8f4mPp8IE3PFWCpm/dFoQnxlrWiMAqq8g?= =?us-ascii?Q?Tj+eAzb7AaTxWkorlEbhOF9XWVQNimqO+QZIFX6yDgwlsYo+kk4b++QHq5j/?= =?us-ascii?Q?fnBD0KgQ5vrr92R9jRj7/OQ/1HauyKtNpqUS5YVf7PuCshdEDz7ux/tbKvMu?= =?us-ascii?Q?eQFDhsKcXskTds32uw/dKRMq0GwBrLK/5zQsPFlsfsiV1bHbc4ALQOzka/pL?= =?us-ascii?Q?7ccDZpkwzZIwA960Xfpom7OVaky4qXRCdy+9QIFRGaEUXh3jsRgCVrYr22Pp?= =?us-ascii?Q?gUxDqkF0SqjdofCElFlgUEy0dx79XXE/NA/1qaoJPIFJRO6w?= X-OriginatorOrg: nxp.com X-MS-Exchange-CrossTenant-Network-Message-Id: a4a35c36-d705-421e-70af-08deb1eb79c5 X-MS-Exchange-CrossTenant-AuthSource: PA4PR04MB9366.eurprd04.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 14 May 2026 19:03:25.3173 (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: WhajEfDtF9u8NNIxJvklBflcQYxvjJrHmc349Up5AjfyshA3YcQxX8W2tY8uATAkjg9X789xhNQAiz/TZrGcgQ== X-MS-Exchange-Transport-CrossTenantHeadersStamped: AM7PR04MB6806 On Wed, May 13, 2026 at 11:49:21AM +0900, Koichiro Den wrote: > ntb_db_event() expects the vector number to be relative to the first > doorbell vector starting at 0. > > Vector 0 is reserved for link events in the EPF driver, so doorbells > start at vector 1. However, both supported peers (ntb_hw_epf with > pci-epf-ntb, and pci-epf-vntb) have historically skipped vector 1 and > started doorbells at vector 2. > > Pass (irq_no - 2) to ntb_db_event() so doorbells are reported as 0..N-1. > If irq_no == 1 is ever observed, warn and ignore it, since the slot is > reserved in the legacy layout and reporting it as DB#0 would collide with > the real DB#0 slot. > > Fixes: 812ce2f8d14e ("NTB: Add support for EPF PCI Non-Transparent Bridge") > Suggested-by: Dave Jiang > Signed-off-by: Koichiro Den > --- Reviewed-by: Frank Li > Changes since v3: > - Ignore the reserved legacy slot instead of reporting it as DB#0. > - Drop a Reviewed-by tag due to the behavior change. > > drivers/ntb/hw/epf/ntb_hw_epf.c | 16 +++++++++++++--- > 1 file changed, 13 insertions(+), 3 deletions(-) > > diff --git a/drivers/ntb/hw/epf/ntb_hw_epf.c b/drivers/ntb/hw/epf/ntb_hw_epf.c > index c0bab3292075..7b0fc7ef00c6 100644 > --- a/drivers/ntb/hw/epf/ntb_hw_epf.c > +++ b/drivers/ntb/hw/epf/ntb_hw_epf.c > @@ -81,6 +81,12 @@ enum epf_ntb_bar { > NTB_BAR_NUM, > }; > > +enum epf_irq_slot { > + EPF_IRQ_LINK = 0, > + EPF_IRQ_RESERVED_DB, /* Historically skipped slot */ > + EPF_IRQ_DB_START, > +}; > + > #define NTB_EPF_MAX_MW_COUNT (NTB_BAR_NUM - BAR_MW1) > > struct ntb_epf_dev { > @@ -334,10 +340,14 @@ static irqreturn_t ntb_epf_vec_isr(int irq, void *dev) > irq_no = irq - ndev->irq_base; > ndev->db_val = irq_no + 1; > > - if (irq_no == 0) > + if (irq_no == EPF_IRQ_LINK) { > ntb_link_event(&ndev->ntb); > - else > - ntb_db_event(&ndev->ntb, irq_no); > + } else if (irq_no == EPF_IRQ_RESERVED_DB) { > + dev_warn_ratelimited(ndev->dev, > + "Unexpected reserved doorbell slot IRQ received\n"); > + } else { > + ntb_db_event(&ndev->ntb, irq_no - EPF_IRQ_DB_START); > + } > > return IRQ_HANDLED; > } > -- > 2.51.0 >