net: stmmac: Parse FIFO sizes from feature registers

New version of this core encode the FIFO sizes in one of the feature
registers. Use these sizes as default, but still allow device tree to
override them for backwards compatibility.

Reviewed-by: Mikko Perttunen <[email protected]>
Signed-off-by: Thierry Reding <[email protected]>
Signed-off-by: David S. Miller <[email protected]>

diff --git a/drivers/net/ethernet/stmicro/stmmac/common.h b/drivers/net/ethernet/stmicro/stmmac/common.h
index 04d9245b7149ce663b0827a158901a10b58ea701..3ca36744007beb059152915d939d52d7c3c338e4 100644 (file)
--- a/drivers/net/ethernet/stmicro/stmmac/common.h
+++ b/drivers/net/ethernet/stmicro/stmmac/common.h
@@ -324,6 +324,9 @@ struct dma_features {
        unsigned int number_tx_queues;
        /* Alternate (enhanced) DESC mode */
        unsigned int enh_desc;
+       /* TX and RX FIFO sizes */
+       unsigned int tx_fifo_size;
+       unsigned int rx_fifo_size;
 };
 
 /* GMAC TX FIFO is 8K, Rx FIFO is 16K */

diff --git a/drivers/net/ethernet/stmicro/stmmac/dwmac4.h b/drivers/net/ethernet/stmicro/stmmac/dwmac4.h
index db45134fddf04e50c703254b8570b744004123f8..83f5e953e291c9e7328b60e909fe137ce3c47f10 100644 (file)
--- a/drivers/net/ethernet/stmicro/stmmac/dwmac4.h
+++ b/drivers/net/ethernet/stmicro/stmmac/dwmac4.h
@@ -148,6 +148,8 @@ enum power_event {
 /* MAC HW features1 bitmap */
 #define GMAC_HW_FEAT_AVSEL             BIT(20)
 #define GMAC_HW_TSOEN                  BIT(18)
+#define GMAC_HW_TXFIFOSIZE             GENMASK(10, 6)
+#define GMAC_HW_RXFIFOSIZE             GENMASK(4, 0)
 
 /* MAC HW features2 bitmap */
 #define GMAC_HW_FEAT_TXCHCNT           GENMASK(21, 18)

diff --git a/drivers/net/ethernet/stmicro/stmmac/dwmac4_dma.c b/drivers/net/ethernet/stmicro/stmmac/dwmac4_dma.c
index f97b0d5d998742efcad71972bd74ce40cc02afad..55270933bae1d0c304b0ea6550a445bf439b2670 100644 (file)
--- a/drivers/net/ethernet/stmicro/stmmac/dwmac4_dma.c
+++ b/drivers/net/ethernet/stmicro/stmmac/dwmac4_dma.c
@@ -294,6 +294,11 @@ static void dwmac4_get_hw_feature(void __iomem *ioaddr,
        hw_cap = readl(ioaddr + GMAC_HW_FEATURE1);
        dma_cap->av = (hw_cap & GMAC_HW_FEAT_AVSEL) >> 20;
        dma_cap->tsoen = (hw_cap & GMAC_HW_TSOEN) >> 18;
+       /* RX and TX FIFO sizes are encoded as log2(n / 128). Undo that by
+        * shifting and store the sizes in bytes.
+        */
+       dma_cap->tx_fifo_size = 128 << ((hw_cap & GMAC_HW_TXFIFOSIZE) >> 6);
+       dma_cap->rx_fifo_size = 128 << ((hw_cap & GMAC_HW_RXFIFOSIZE) >> 0);
        /* MAC HW feature2 */
        hw_cap = readl(ioaddr + GMAC_HW_FEATURE2);
        /* TX and RX number of channels */

diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
index eba9088e1f616668fc7cb71e6f1ba16c7a4497c5..78f6ec2d165b7b225422e36cf45c981ddcac551e 100644 (file)
--- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
@@ -1281,6 +1281,9 @@ static void stmmac_dma_operation_mode(struct stmmac_priv *priv)
 {
        int rxfifosz = priv->plat->rx_fifo_size;
 
+       if (rxfifosz == 0)
+               rxfifosz = priv->dma_cap.rx_fifo_size;
+
        if (priv->plat->force_thresh_dma_mode)
                priv->hw->dma->dma_mode(priv->ioaddr, tc, tc, rxfifosz);
        else if (priv->plat->force_sf_dma_mode || priv->plat->tx_coe) {