[PATCH v1 2/3] net: bcmgenet: use optional max DMA burst size property

matthias.bgg
2019-10-11T18:48:38Z

From: Matthias Brugger <mbrugger@suse.com>

Depending on the HW, the maximal usable DMA burst size can vary.
If not set accordingly a timeout in the transmit queue happens and no
package can be sent. Read to optional max-burst-sz property, if not
present, fallback to the standard value.

Signed-off-by: Matthias Brugger <mbrugger@suse.com>
---

drivers/net/ethernet/broadcom/genet/bcmgenet.c | 13 +++++++++++--
drivers/net/ethernet/broadcom/genet/bcmgenet.h | 1 +
2 files changed, 12 insertions(+), 2 deletions(-)

diff --git a/drivers/net/ethernet/broadcom/genet/bcmgenet.c b/drivers/net/ethernet/broadcom/genet/bcmgenet.c
index 12cb77ef1081..a7bb822a6d83 100644
--- a/drivers/net/ethernet/broadcom/genet/bcmgenet.c
+++ b/drivers/net/ethernet/broadcom/genet/bcmgenet.c
@@ -2576,7 +2576,8 @@ static int bcmgenet_init_dma(struct bcmgenet_priv *priv)
}

/* Init rDma */
- bcmgenet_rdma_writel(priv, DMA_MAX_BURST_LENGTH, DMA_SCB_BURST_SIZE);
+ bcmgenet_rdma_writel(priv, priv->dma_max_burst_length,
+ DMA_SCB_BURST_SIZE);

/* Initialize Rx queues */
ret = bcmgenet_init_rx_queues(priv->dev);
@@ -2589,7 +2590,8 @@ static int bcmgenet_init_dma(struct bcmgenet_priv *priv)
}

/* Init tDma */
- bcmgenet_tdma_writel(priv, DMA_MAX_BURST_LENGTH, DMA_SCB_BURST_SIZE);
+ bcmgenet_tdma_writel(priv, priv->dma_max_burst_length,
+ DMA_SCB_BURST_SIZE);

/* Initialize Tx queues */
bcmgenet_init_tx_queues(priv->dev);
@@ -3522,6 +3524,13 @@ static int bcmgenet_probe(struct platform_device *pdev)

clk_prepare_enable(priv->clk);

+ if (dn) {
+ of_property_read_u32(dn, "dma-burst-sz",
+ &priv->dma_max_burst_length);
+ } else {
+ priv->dma_max_burst_length = DMA_MAX_BURST_LENGTH;
+ }
+
bcmgenet_set_hw_params(priv);

/* Mii wait queue */
diff --git a/drivers/net/ethernet/broadcom/genet/bcmgenet.h b/drivers/net/ethernet/broadcom/genet/bcmgenet.h
index 4a8fc03d82fd..897f356eb376 100644
--- a/drivers/net/ethernet/broadcom/genet/bcmgenet.h
+++ b/drivers/net/ethernet/broadcom/genet/bcmgenet.h
@@ -663,6 +663,7 @@ struct bcmgenet_priv {
bool crc_fwd_en;

unsigned int dma_rx_chk_bit;
+ unsigned int dma_max_burst_length;

u32 msg_enable;

--
2.23.0