On 23.02.2017 19:24, Thierry Reding wrote:
From: Thierry Reding <treding@xxxxxxxxxx>
Program the receive queue size based on the RX FIFO size and enable
hardware flow control for large FIFOs.
Signed-off-by: Thierry Reding <treding@xxxxxxxxxx>
---
drivers/net/ethernet/stmicro/stmmac/dwmac4.h | 12 +++++++
drivers/net/ethernet/stmicro/stmmac/dwmac4_dma.c | 43 ++++++++++++++++++++++--
2 files changed, 53 insertions(+), 2 deletions(-)
diff --git a/drivers/net/ethernet/stmicro/stmmac/dwmac4.h b/drivers/net/ethernet/stmicro/stmmac/dwmac4.h
index db45134fddf0..9acc1f1252b3 100644
--- a/drivers/net/ethernet/stmicro/stmmac/dwmac4.h
+++ b/drivers/net/ethernet/stmicro/stmmac/dwmac4.h
@@ -180,6 +180,7 @@ enum power_event {
#define MTL_OP_MODE_TSF BIT(1)
#define MTL_OP_MODE_TQS_MASK GENMASK(24, 16)
+#define MTL_OP_MODE_TQS_SHIFT 16
#define MTL_OP_MODE_TTC_MASK 0x70
#define MTL_OP_MODE_TTC_SHIFT 4
@@ -193,6 +194,17 @@ enum power_event {
#define MTL_OP_MODE_TTC_384 (6 << MTL_OP_MODE_TTC_SHIFT)
#define MTL_OP_MODE_TTC_512 (7 << MTL_OP_MODE_TTC_SHIFT)
+#define MTL_OP_MODE_RQS_MASK GENMASK(29, 20)
+#define MTL_OP_MODE_RQS_SHIFT 20
+
+#define MTL_OP_MODE_RFD_MASK GENMASK(19, 14)
+#define MTL_OP_MODE_RFD_SHIFT 14
+
+#define MTL_OP_MODE_RFA_MASK GENMASK(13, 8)
+#define MTL_OP_MODE_RFA_SHIFT 8
+
+#define MTL_OP_MODE_EHFC BIT(7)
+
#define MTL_OP_MODE_RTC_MASK 0x18
#define MTL_OP_MODE_RTC_SHIFT 3
diff --git a/drivers/net/ethernet/stmicro/stmmac/dwmac4_dma.c b/drivers/net/ethernet/stmicro/stmmac/dwmac4_dma.c
index 8d249f3b34c8..03d230201960 100644
--- a/drivers/net/ethernet/stmicro/stmmac/dwmac4_dma.c
+++ b/drivers/net/ethernet/stmicro/stmmac/dwmac4_dma.c
@@ -185,8 +185,9 @@ static void dwmac4_rx_watchdog(void __iomem *ioaddr, u32 riwt)
}
static void dwmac4_dma_chan_op_mode(void __iomem *ioaddr, int txmode,
- int rxmode, u32 channel)
+ int rxmode, u32 channel, int rxfifosz)
{
+ unsigned int rqs = rxfifosz / 256 - 1;
u32 mtl_tx_op, mtl_rx_op, mtl_rx_int;
/* Following code only done for channel 0, other channels not yet
@@ -252,6 +253,44 @@ static void dwmac4_dma_chan_op_mode(void __iomem *ioaddr, int txmode,
mtl_rx_op |= MTL_OP_MODE_RTC_128;
}
+ mtl_rx_op &= ~MTL_OP_MODE_RQS_MASK;
+ mtl_rx_op |= rqs << MTL_OP_MODE_RQS_SHIFT;
+
+ /* enable flow control only if each channel gets 4 KiB or more FIFO */
+ if (rxfifosz >= 4096) {
+ unsigned int rfd, rfa;
+
+ mtl_rx_op |= MTL_OP_MODE_EHFC;
+
+ switch (rxfifosz) {
+ case 4096:
+ rfd = 0x03;
+ rfa = 0x01;
+ break;
+
+ case 8192:
+ rfd = 0x06;
+ rfa = 0x0a;
+ break;
+
+ case 16384:
+ rfd = 0x06;
+ rfa = 0x12;
+ break;
+
+ default:
+ rfd = 0x06;
+ rfa = 0x1e;
+ break;
+ }
Are these values correct? In the 4096 case, rfd > rfa, in all other
cases the other way around. In any case it would be useful to have a
comment clarifying the thresholds in bytes.
+
+ mtl_rx_op &= ~MTL_OP_MODE_RFD_MASK;
+ mtl_rx_op |= rfd << MTL_OP_MODE_RFD_SHIFT;
+
+ mtl_rx_op &= ~MTL_OP_MODE_RFA_MASK;
+ mtl_rx_op |= rfa << MTL_OP_MODE_RFA_SHIFT;
+ }
+
writel(mtl_rx_op, ioaddr + MTL_CHAN_RX_OP_MODE(channel));
/* Enable MTL RX overflow */
@@ -264,7 +303,7 @@ static void dwmac4_dma_operation_mode(void __iomem *ioaddr, int txmode,
int rxmode, int rxfifosz)
{
/* Only Channel 0 is actually configured and used */
- dwmac4_dma_chan_op_mode(ioaddr, txmode, rxmode, 0);
+ dwmac4_dma_chan_op_mode(ioaddr, txmode, rxmode, 0, rxfifosz);
}
static void dwmac4_get_hw_feature(void __iomem *ioaddr,
--
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