From: Lad Prabhakar The number of CDARq (Current Descriptor Address Register) registers is not fixed to 22 across all SoC variants. For example, the GBETH implementation uses only two entries. Hardcoding the value leads to incorrect resource allocation on such platforms. Pass the DBAT entry count through the per-SoC hardware info struct and use it during probe instead of relying on a fixed constant. This ensures correct descriptor table sizing and initialization across different SoCs. Fixes: feab85c7ccea ("ravb: Add support for RZ/G2L SoC") Cc: stable@vger.kernel.org Signed-off-by: Lad Prabhakar --- drivers/net/ethernet/renesas/ravb.h | 2 +- drivers/net/ethernet/renesas/ravb_main.c | 9 +++++++-- 2 files changed, 8 insertions(+), 3 deletions(-) diff --git a/drivers/net/ethernet/renesas/ravb.h b/drivers/net/ethernet/renesas/ravb.h index 7b48060c250b..d65cd83ddd16 100644 --- a/drivers/net/ethernet/renesas/ravb.h +++ b/drivers/net/ethernet/renesas/ravb.h @@ -1017,7 +1017,6 @@ enum CSR2_BIT { #define CSR2_CSUM_ENABLE (CSR2_RTCP4 | CSR2_RUDP4 | CSR2_RICMP4 | \ CSR2_RTCP6 | CSR2_RUDP6 | CSR2_RICMP6) -#define DBAT_ENTRY_NUM 22 #define RX_QUEUE_OFFSET 4 #define NUM_RX_QUEUE 2 #define NUM_TX_QUEUE 2 @@ -1062,6 +1061,7 @@ struct ravb_hw_info { u32 rx_max_frame_size; u32 rx_buffer_size; u32 rx_desc_size; + u32 dbat_entry_num; unsigned aligned_tx: 1; unsigned coalesce_irqs:1; /* Needs software IRQ coalescing */ diff --git a/drivers/net/ethernet/renesas/ravb_main.c b/drivers/net/ethernet/renesas/ravb_main.c index 9d3bd65b85ff..69d382e8757d 100644 --- a/drivers/net/ethernet/renesas/ravb_main.c +++ b/drivers/net/ethernet/renesas/ravb_main.c @@ -2694,6 +2694,7 @@ static const struct ravb_hw_info ravb_gen2_hw_info = { .rx_buffer_size = SZ_2K + SKB_DATA_ALIGN(sizeof(struct skb_shared_info)), .rx_desc_size = sizeof(struct ravb_ex_rx_desc), + .dbat_entry_num = 22, .aligned_tx = 1, .gptp = 1, .nc_queues = 1, @@ -2717,6 +2718,7 @@ static const struct ravb_hw_info ravb_gen3_hw_info = { .rx_buffer_size = SZ_2K + SKB_DATA_ALIGN(sizeof(struct skb_shared_info)), .rx_desc_size = sizeof(struct ravb_ex_rx_desc), + .dbat_entry_num = 22, .internal_delay = 1, .tx_counters = 1, .multi_irqs = 1, @@ -2743,6 +2745,7 @@ static const struct ravb_hw_info ravb_gen4_hw_info = { .rx_buffer_size = SZ_2K + SKB_DATA_ALIGN(sizeof(struct skb_shared_info)), .rx_desc_size = sizeof(struct ravb_ex_rx_desc), + .dbat_entry_num = 22, .internal_delay = 1, .tx_counters = 1, .multi_irqs = 1, @@ -2769,6 +2772,7 @@ static const struct ravb_hw_info ravb_rzv2m_hw_info = { .rx_buffer_size = SZ_2K + SKB_DATA_ALIGN(sizeof(struct skb_shared_info)), .rx_desc_size = sizeof(struct ravb_ex_rx_desc), + .dbat_entry_num = 22, .multi_irqs = 1, .err_mgmt_irqs = 1, .gptp = 1, @@ -2794,6 +2798,7 @@ static const struct ravb_hw_info gbeth_hw_info = { .rx_max_frame_size = SZ_8K, .rx_buffer_size = SZ_2K, .rx_desc_size = sizeof(struct ravb_rx_desc), + .dbat_entry_num = 2, .aligned_tx = 1, .coalesce_irqs = 1, .tx_counters = 1, @@ -3025,7 +3030,7 @@ static int ravb_probe(struct platform_device *pdev) ravb_parse_delay_mode(np, ndev); /* Allocate descriptor base address table */ - priv->desc_bat_size = sizeof(struct ravb_desc) * DBAT_ENTRY_NUM; + priv->desc_bat_size = sizeof(struct ravb_desc) * info->dbat_entry_num; priv->desc_bat = dma_alloc_coherent(ndev->dev.parent, priv->desc_bat_size, &priv->desc_bat_dma, GFP_KERNEL); if (!priv->desc_bat) { @@ -3035,7 +3040,7 @@ static int ravb_probe(struct platform_device *pdev) error = -ENOMEM; goto out_rpm_put; } - for (q = RAVB_BE; q < DBAT_ENTRY_NUM; q++) + for (q = RAVB_BE; q < info->dbat_entry_num; q++) priv->desc_bat[q].die_dt = DT_EOS; /* Initialise HW timestamp list */ -- 2.43.0 From: Lad Prabhakar On SoCs that only support the best-effort queue and not the network control queue, calling alloc_etherdev_mqs() with fixed values for TX/RX queues is not appropriate. Use the nc_queues flag from the per-SoC match data to determine whether the network control queue is available, and fall back to a single TX/RX queue when it is not. This ensures correct queue allocation across all supported SoCs. Fixes: a92f4f0662bf ("ravb: Add nc_queue to struct ravb_hw_info") Cc: stable@vger.kernel.org Signed-off-by: Lad Prabhakar --- drivers/net/ethernet/renesas/ravb_main.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) diff --git a/drivers/net/ethernet/renesas/ravb_main.c b/drivers/net/ethernet/renesas/ravb_main.c index 69d382e8757d..a200e205825a 100644 --- a/drivers/net/ethernet/renesas/ravb_main.c +++ b/drivers/net/ethernet/renesas/ravb_main.c @@ -2926,13 +2926,14 @@ static int ravb_probe(struct platform_device *pdev) return dev_err_probe(&pdev->dev, PTR_ERR(rstc), "failed to get cpg reset\n"); + info = of_device_get_match_data(&pdev->dev); + ndev = alloc_etherdev_mqs(sizeof(struct ravb_private), - NUM_TX_QUEUE, NUM_RX_QUEUE); + info->nc_queues ? NUM_TX_QUEUE : 1, + info->nc_queues ? NUM_RX_QUEUE : 1); if (!ndev) return -ENOMEM; - info = of_device_get_match_data(&pdev->dev); - ndev->features = info->net_features; ndev->hw_features = info->net_hw_features; ndev->vlan_features = info->vlan_features; -- 2.43.0 From: Lad Prabhakar Ensure TX descriptor type fields are written in a safe order so the DMA engine does not begin processing a chain before all descriptors are fully initialised. For multi-descriptor transmissions the driver writes DT_FEND into the last descriptor and DT_FSTART into the first. The DMA engine starts processing when it sees DT_FSTART. If the compiler or CPU reorders the writes and publishes DT_FSTART before DT_FEND, the DMA can start early and process an incomplete chain, leading to corrupted transmissions or DMA errors. Fix this by writing DT_FEND before the dma_wmb() barrier, executing dma_wmb() immediately before DT_FSTART (or DT_FSINGLE in the single descriptor case), and then adding a wmb() after the type updates to ensure CPU-side ordering before ringing the hardware doorbell. On an RZ/G2L platform running an RT kernel, this reordering hazard was observed as TX stalls and timeouts: [ 372.968431] NETDEV WATCHDOG: end0 (ravb): transmit queue 0 timed out [ 372.968494] WARNING: CPU: 0 PID: 10 at net/sched/sch_generic.c:467 dev_watchdog+0x4a4/0x4ac [ 373.969291] ravb 11c20000.ethernet end0: transmit timed out, status 00000000, resetting... This change enforces the required ordering and prevents the DMA engine from observing DT_FSTART before the rest of the descriptor chain is valid. Fixes: 2f45d1902acf ("ravb: minimize TX data copying") Cc: stable@vger.kernel.org Co-developed-by: Fabrizio Castro Signed-off-by: Fabrizio Castro Signed-off-by: Lad Prabhakar --- drivers/net/ethernet/renesas/ravb_main.c | 14 +++++++++----- 1 file changed, 9 insertions(+), 5 deletions(-) diff --git a/drivers/net/ethernet/renesas/ravb_main.c b/drivers/net/ethernet/renesas/ravb_main.c index a200e205825a..2a995fa9bfff 100644 --- a/drivers/net/ethernet/renesas/ravb_main.c +++ b/drivers/net/ethernet/renesas/ravb_main.c @@ -2211,15 +2211,19 @@ static netdev_tx_t ravb_start_xmit(struct sk_buff *skb, struct net_device *ndev) skb_tx_timestamp(skb); } - /* Descriptor type must be set after all the above writes */ - dma_wmb(); + + /* For multi-descriptors set DT_FEND before calling dma_wmb() */ if (num_tx_desc > 1) { desc->die_dt = DT_FEND; desc--; - desc->die_dt = DT_FSTART; - } else { - desc->die_dt = DT_FSINGLE; } + + /* Descriptor type must be set after all the above writes */ + dma_wmb(); + desc->die_dt = (num_tx_desc > 1) ? DT_FSTART : DT_FSINGLE; + + /* Ensure data is written to RAM before initiating DMA transfer */ + wmb(); ravb_modify(ndev, TCCR, TCCR_TSRQ0 << q, TCCR_TSRQ0 << q); priv->cur_tx[q] += num_tx_desc; -- 2.43.0