net: ethernet: mtk_eth_soc: add support for Wireless Ethernet Dispatch (WED)

The Wireless Ethernet Dispatch subsystem on the MT7622 SoC can be
configured to intercept and handle access to the DMA queues and
PCIe interrupts for a MT7615/MT7915 wireless card.
It can manage the internal WDMA (Wireless DMA) controller, which allows
ethernet packets to be passed from the packet switch engine (PSE) to the
wireless card, bypassing the CPU entirely.
This can be used to implement hardware flow offloading from ethernet to
WLAN.

Signed-off-by: Felix Fietkau <nbd@nbd.name>
Signed-off-by: David S. Miller <davem@davemloft.net>

Author: nbd168

drivers/net/ethernet/mediatek/Kconfig

@@ -7,6 +7,10 @@ config NET_VENDOR_MEDIATEK
 
 if NET_VENDOR_MEDIATEK
 
+config NET_MEDIATEK_SOC_WED
+	depends on ARCH_MEDIATEK || COMPILE_TEST
+	def_bool NET_MEDIATEK_SOC != n
+
 config NET_MEDIATEK_SOC
 	tristate "MediaTek SoC Gigabit Ethernet support"
 	depends on NET_DSA || !NET_DSA

drivers/net/ethernet/mediatek/Makefile

@@ -5,4 +5,9 @@
 
 obj-$(CONFIG_NET_MEDIATEK_SOC) += mtk_eth.o
 mtk_eth-y := mtk_eth_soc.o mtk_sgmii.o mtk_eth_path.o mtk_ppe.o mtk_ppe_debugfs.o mtk_ppe_offload.o
+mtk_eth-$(CONFIG_NET_MEDIATEK_SOC_WED) += mtk_wed.o
+ifdef CONFIG_DEBUG_FS
+mtk_eth-$(CONFIG_NET_MEDIATEK_SOC_WED) += mtk_wed_debugfs.o
+endif
+obj-$(CONFIG_NET_MEDIATEK_SOC_WED) += mtk_wed_ops.o
 obj-$(CONFIG_NET_MEDIATEK_STAR_EMAC) += mtk_star_emac.o

drivers/net/ethernet/mediatek/mtk_eth_soc.c

@@ -24,6 +24,7 @@
 #include <net/dsa.h>
 
 #include "mtk_eth_soc.h"
+#include "mtk_wed.h"
 
 static int mtk_msg_level = -1;
 module_param_named(msg_level, mtk_msg_level, int, 0);
@@ -3170,6 +3171,22 @@ static int mtk_probe(struct platform_device *pdev)
 		}
 	}
 
+	for (i = 0;; i++) {
+		struct device_node *np = of_parse_phandle(pdev->dev.of_node,
+							  "mediatek,wed", i);
+		static const u32 wdma_regs[] = {
+			MTK_WDMA0_BASE,
+			MTK_WDMA1_BASE
+		};
+		void __iomem *wdma;
+
+		if (!np || i >= ARRAY_SIZE(wdma_regs))
+			break;
+
+		wdma = eth->base + wdma_regs[i];
+		mtk_wed_add_hw(np, eth, wdma, i);
+	}
+
 	for (i = 0; i < 3; i++) {
 		if (MTK_HAS_CAPS(eth->soc->caps, MTK_SHARED_INT) && i > 0)
 			eth->irq[i] = eth->irq[0];

drivers/net/ethernet/mediatek/mtk_eth_soc.h

@@ -295,6 +295,9 @@
 #define MTK_GDM1_TX_GPCNT	0x2438
 #define MTK_STAT_OFFSET		0x40
 
+#define MTK_WDMA0_BASE		0x2800
+#define MTK_WDMA1_BASE		0x2c00
+
 /* QDMA descriptor txd4 */
 #define TX_DMA_CHKSUM		(0x7 << 29)
 #define TX_DMA_TSO		BIT(28)