openwrt/target/linux/mediatek/patches-5.4/1012-pci-pcie-mediatek-add-support-for-coherent-DMA.patch
Felix Fietkau 920d975cab mediatek: enable coherent DMA for ethernet and PCI
Improves performance by eliminating the need for extra cache flushes

Signed-off-by: Felix Fietkau <nbd@nbd.name>
2020-09-04 19:42:35 +02:00

109 lines
2.8 KiB
Diff

From: Felix Fietkau <nbd@nbd.name>
Date: Fri, 4 Sep 2020 18:42:42 +0200
Subject: [PATCH] pci: pcie-mediatek: add support for coherent DMA
It improves performance by eliminating the need for a cache flush for DMA on
attached devices
Signed-off-by: Felix Fietkau <nbd@nbd.name>
---
--- a/arch/arm64/boot/dts/mediatek/mt7622.dtsi
+++ b/arch/arm64/boot/dts/mediatek/mt7622.dtsi
@@ -801,6 +801,8 @@
reg = <0 0x1a143000 0 0x1000>;
reg-names = "port0";
mediatek,pcie-cfg = <&pciecfg>;
+ mediatek,hifsys = <&hifsys>;
+ mediatek,cci-control = <&cci_control2>;
#address-cells = <3>;
#size-cells = <2>;
interrupts = <GIC_SPI 228 IRQ_TYPE_LEVEL_LOW>;
@@ -818,6 +820,7 @@
bus-range = <0x00 0xff>;
ranges = <0x82000000 0 0x20000000 0x0 0x20000000 0 0x8000000>;
status = "disabled";
+ dma-coherent;
slot0: pcie@0,0 {
reg = <0x0000 0 0 0 0>;
@@ -844,6 +847,8 @@
reg = <0 0x1a145000 0 0x1000>;
reg-names = "port1";
mediatek,pcie-cfg = <&pciecfg>;
+ mediatek,hifsys = <&hifsys>;
+ mediatek,cci-control = <&cci_control2>;
#address-cells = <3>;
#size-cells = <2>;
interrupts = <GIC_SPI 229 IRQ_TYPE_LEVEL_LOW>;
@@ -862,6 +867,7 @@
bus-range = <0x00 0xff>;
ranges = <0x82000000 0 0x28000000 0x0 0x28000000 0 0x8000000>;
status = "disabled";
+ dma-coherent;
slot1: pcie@1,0 {
reg = <0x0800 0 0 0 0>;
@@ -921,6 +927,11 @@
};
};
+ hifsys: syscon@1af00000 {
+ compatible = "mediatek,mt7622-hifsys", "syscon";
+ reg = <0 0x1af00000 0 0x70>;
+ };
+
ethsys: syscon@1b000000 {
compatible = "mediatek,mt7622-ethsys",
"syscon";
--- a/drivers/pci/controller/pcie-mediatek.c
+++ b/drivers/pci/controller/pcie-mediatek.c
@@ -20,6 +20,7 @@
#include <linux/of_address.h>
#include <linux/of_pci.h>
#include <linux/of_platform.h>
+#include <linux/of_address.h>
#include <linux/pci.h>
#include <linux/phy/phy.h>
#include <linux/platform_device.h>
@@ -139,6 +140,11 @@
#define PCIE_LINK_STATUS_V2 0x804
#define PCIE_PORT_LINKUP_V2 BIT(10)
+/* DMA channel mapping */
+#define HIFSYS_DMA_AG_MAP 0x008
+#define HIFSYS_DMA_AG_MAP_PCIE0 BIT(0)
+#define HIFSYS_DMA_AG_MAP_PCIE1 BIT(1)
+
struct mtk_pcie_port;
/**
@@ -1068,6 +1074,27 @@ static int mtk_pcie_setup(struct mtk_pci
}
}
+ if (of_dma_is_coherent(node)) {
+ struct regmap *con;
+ u32 mask;
+
+ con = syscon_regmap_lookup_by_phandle(node,
+ "mediatek,cci-control");
+ /* enable CPU/bus coherency */
+ if (!IS_ERR(con))
+ regmap_write(con, 0, 3);
+
+ con = syscon_regmap_lookup_by_phandle(node,
+ "mediatek,hifsys");
+ if (IS_ERR(con)) {
+ dev_err(dev, "missing hifsys node\n");
+ return PTR_ERR(con);
+ }
+
+ mask = HIFSYS_DMA_AG_MAP_PCIE0 | HIFSYS_DMA_AG_MAP_PCIE1;
+ regmap_update_bits(con, HIFSYS_DMA_AG_MAP, mask, mask);
+ }
+
for_each_available_child_of_node(node, child) {
int slot;