Re: [PATCH net-next 2/2] net: macb: configure ENST registers for all queues
From: Nicolai Buchwitz <hidden>
Date: 2026-07-24 19:57:53
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Hi Vineeth On 24.7.2026 06:32, Vineeth Karumanchi wrote:
The initial "tc" command was not overwriting the reset value of ENST
registers if only a subset of queues were configured, leading to an
invalid setup. To fix this, configure all queues unconditionally.
Unconfigured queues are zero-initialized via kcalloc(), ensuring a
complete and consistent configuration.
The queue_id field in struct macb_queue_enst_config becomes redundant
once the array is indexed by queue id, so drop it.
Key changes:
- Drop queue_id from struct macb_queue_enst_config
- Allocate enst_queue[] based on bp->num_queues instead of
conf->num_entries
- Index enst_queue[] directly with the queue number
- Program ENST registers for all queues
Fixes: 89934dbf169e ("net: macb: Add TAPRIO traffic scheduling
support")In addition to what Théo already mentioned: The series targets net-next, but if this is a real bug fix it should probably be routed via net. The offending commit is in stable since v6.18.
quoted hunk ↗ jump to hunk
Signed-off-by: Vineeth Karumanchi <redacted> --- drivers/net/ethernet/cadence/macb.h | 2 -- drivers/net/ethernet/cadence/macb_main.c | 20 +++++++++----------- 2 files changed, 9 insertions(+), 13 deletions(-)diff --git a/drivers/net/ethernet/cadence/macb.hb/drivers/net/ethernet/cadence/macb.h index a11052565436..4cc9aa9b2f9e 100644--- a/drivers/net/ethernet/cadence/macb.h +++ b/drivers/net/ethernet/cadence/macb.h@@ -1490,7 +1490,6 @@ struct macb_platform_data { * @start_time_mask: Bitmask representing the start time for thequeue * @on_time_bytes: "on" time nsec expressed in bytes * @off_time_bytes: "off" time nsec expressed in bytes - * @queue_id: Identifier for the queue * * This structure holds the configuration parameters for an ENST queue, * used to control time-based transmission scheduling in the MACB driver.@@ -1499,7 +1498,6 @@ struct macb_queue_enst_config { u32 start_time_mask; u32 on_time_bytes; u32 off_time_bytes; - u8 queue_id; }; #endif /* _MACB_H */diff --git a/drivers/net/ethernet/cadence/macb_main.cb/drivers/net/ethernet/cadence/macb_main.c index d394f1f43b68..d58430fe9c41 100644--- a/drivers/net/ethernet/cadence/macb_main.c +++ b/drivers/net/ethernet/cadence/macb_main.c@@ -4329,7 +4329,7 @@ static int macb_taprio_setup_replace(structnet_device *ndev, struct macb_queue *queue; u32 queue_mask; u8 queue_id; - size_t i; + size_t i, q; int err; if (conf->num_entries > bp->num_queues) {@@ -4357,7 +4357,7 @@ static int macb_taprio_setup_replace(structnet_device *ndev, return -EINVAL; } - enst_queue = kcalloc(conf->num_entries, sizeof(*enst_queue), GFP_KERNEL); + enst_queue = kcalloc(bp->num_queues, sizeof(*enst_queue), GFP_KERNEL); if (unlikely(!enst_queue)) return -ENOMEM;@@ -4416,13 +4416,12 @@ static int macb_taprio_setup_replace(structnet_device *ndev, goto cleanup; } - enst_queue[i].queue_id = queue_id; - enst_queue[i].start_time_mask = + enst_queue[queue_id].start_time_mask = (start_time_sec << GEM_START_TIME_SEC_OFFSET) | start_time_nsec; - enst_queue[i].on_time_bytes = + enst_queue[queue_id].on_time_bytes = enst_ns_to_hw_units(entry->interval, speed); - enst_queue[i].off_time_bytes = + enst_queue[queue_id].off_time_bytes = enst_ns_to_hw_units(conf->cycle_time - entry->interval, speed); configured_queues |= entry->gate_mask;@@ -4448,15 +4447,14 @@ static int macb_taprio_setup_replace(structnet_device *ndev, gem_writel(bp, ENST_CONTROL, queue_mask << GEM_ENST_DISABLE_QUEUE_OFFSET); - for (i = 0; i < conf->num_entries; i++) { - queue = &bp->queues[enst_queue[i].queue_id]; + for (q = 0, queue = bp->queues; q < bp->num_queues; ++q, ++queue) { /* Configure queue timing registers */ queue_writel(queue, ENST_START_TIME, - enst_queue[i].start_time_mask); + enst_queue[q].start_time_mask); queue_writel(queue, ENST_ON_TIME, - enst_queue[i].on_time_bytes); + enst_queue[q].on_time_bytes); queue_writel(queue, ENST_OFF_TIME, - enst_queue[i].off_time_bytes); + enst_queue[q].off_time_bytes); } /* Enable ENST for all configured queues in one write */
Regards, Nicolai