1 说明

zynq 平台，需要用到 pl (FPGA)端发送中断给 ps端(ARM)，发送的中断名称为 IRQ_F2P[15:0]，该中断一共有16个，中断号分别为 61-68, 84-91。本文针对该中断在linux 环境开，开发驱动，驱动方式采用 uio 模型。

2 开发环境

1、软件环境：ubuntu14.04

vivado：2015.04

2、linux 内核版本：zynq7010黑金开发板配套内核包，linux 版本4.0.0

3、硬件环境：黑金开发板 zynq7010.

3 操作

3.1 PL 部分

3.2 PS 部分

3.2.1 中断号说明

对于zynq 驱动，需要注意：

1、对于SPI中断，则对应到Linux 的中断标号，为芯片datasheet的中断号 -16.

例如中断号为 30，则对应的linux 中断号为 30 -16 = 14.

2、对于非 SPI 中断，则对应的 linux 中断标号，为芯片 datasheet 的中断号 -32.

例如 IRQ_F2P中断，中断号为 61，则对应的 linux 中断号为 61 - 32 = 29.

3.2.2 修改设备树

本文中，使用的中断为 irq_f2p 的中断号 61，那么对应的 linux 中断号为 29 = 0x19。

修改zynq 7010 的设备树文件 AX7010，在dts中，增加uio 中断。

uio@0{

compatible="generic-uio";

status="okay";

interrupt-controller;

interrupt-parent=<0x4>;

interrupts=<0x0 0x1d 0x1>;

};

有些设备树版本不同，需要增加 reg参数，所以uio 的描述多增加一行 reg = <0 0>：

uio@0{

reg = <0 0>

compatible="generic-uio";

status="okay";

interrupt-controller;

interrupt-parent=<0x4>;

interrupts=<0x0 0x1d 0x1>;

};

另外，增加命令行参数，加上 uio的参数 uio_pdrv_genirq.of_id=generic-uio

chosen {

bootargs = "console=ttyPS0,115200 root=/dev/mmcblk0p2 rw earlyprintk rootfstype=ext4 rootwait devtmpfs.mount=1 uio_pdrv_genirq.of_id=generic-uio";

};

如下是修改后的 dts 文件，一共开了4个uio 中断，因为有一些中断号被占用，故没使用 62 中断:

/dts-v1/;

/ {

#address-cells = <0x1>;

#size-cells = <0x1>;

compatible = "xlnx,zynq-7000";

model = "ALINX-AX7010";

chosen {

bootargs = "console=ttyPS0,115200 root=/dev/mmcblk0p2 rw earlyprintk rootfstype=ext4 rootwait devtmpfs.mount=1 uio_pdrv_genirq.of_id=generic-uio";

};

aliases {

serial0 = "/amba/serial@e0001000";

ethernet0 = "/amba/ethernet@e000b000";

spi0 = "/amba/spi@e000d000";

};

memory {

device_type = "memory";

reg = <0x0 0x20000000>;

};

cpus {

#address-cells = <0x1>;

#size-cells = <0x0>;

cpu@0 {

compatible = "arm,cortex-a9";

device_type = "cpu";

reg = <0x0>;

clocks = <0x1 0x3>;

clock-latency = <0x3e8>;

cpu0-supply = <0x2>;

operating-points = <0x9eb10 0xf4240 0x4f588 0xf4240>;

};

cpu@1 {

compatible = "arm,cortex-a9";

device_type = "cpu";

reg = <0x1>;

clocks = <0x1 0x3>;

};

};

pmu {

compatible = "arm,cortex-a9-pmu";

interrupts = <0x0 0x5 0x4 0x0 0x6 0x4>;

interrupt-parent = <0x3>;

reg = <0xf8891000 0x1000 0xf8893000 0x1000>;

};

fixedregulator@0 {

compatible = "regulator-fixed";

regulator-name = "VCCPINT";

regulator-min-microvolt = <0xf4240>;

regulator-max-microvolt = <0xf4240>;

regulator-boot-on;

regulator-always-on;

linux,phandle = <0x2>;

phandle = <0x2>;

};

amba {

compatible = "simple-bus";

#address-cells = <0x1>;

#size-cells = <0x1>;

interrupt-parent = <0x3>;

ranges;

//u-boot,dm-pre-reloc;

adc@f8007100 {

compatible = "xlnx,zynq-xadc-1.00.a";

reg = <0xf8007100 0x20>;

interrupts = <0x0 0x7 0x4>;

interrupt-parent = <0x3>;

clocks = <0x1 0xc>;

};

can@e0008000 {

compatible = "xlnx,zynq-can-1.0";

status = "disabled";

clocks = <0x1 0x13 0x1 0x24>;

clock-names = "can_clk", "pclk";

reg = <0xe0008000 0x1000>;

interrupts = <0x0 0x1c 0x4>;

interrupt-parent = <0x3>;

tx-fifo-depth = <0x40>;

rx-fifo-depth = <0x40>;

};

can@e0009000 {

compatible = "xlnx,zynq-can-1.0";

status = "disabled";

clocks = <0x1 0x14 0x1 0x25>;

clock-names = "can_clk", "pclk";

reg = <0xe0009000 0x1000>;

interrupts = <0x0 0x33 0x4>;

interrupt-parent = <0x3>;

tx-fifo-depth = <0x40>;

rx-fifo-depth = <0x40>;

};

gpio@e000a000 {

compatible = "xlnx,zynq-gpio-1.0";

#gpio-cells = <0x2>;

clocks = <0x1 0x2a>;

gpio-controller;

interrupt-parent = <0x3>;

interrupts = <0x0 0x14 0x4>;

reg = <0xe000a000 0x1000>;

emio-gpio-width = <0x40>;

gpio-mask-high = <0x0>;

gpio-mask-low = <0x5600>;

linux,phandle = <0x6>;

phandle = <0x6>;

};

i2c@e0004000 {

compatible = "cdns,i2c-r1p10";

status = "okay";

clocks = <0x1 0x26>;

interrupt-parent = <0x3>;

interrupts = <0x0 0x19 0x4>;

reg = <0xe0004000 0x1000>;

#address-cells = <0x1>;

#size-cells = <0x0>;

clock-frequency = <0x61a80>;

};

i2c@e0005000 {

compatible = "cdns,i2c-r1p10";

status = "okay";

clocks = <0x1 0x27>;

interrupt-parent = <0x3>;

interrupts = <0x0 0x30 0x4>;

reg = <0xe0005000 0x1000>;

#address-cells = <0x1>;

#size-cells = <0x0>;

clock-frequency = <0x61a80>;

linux,phandle = <0x8>;

phandle = <0x8>;

edt_ft5x06@38 {

compatible = "edt,edt-ft5406";

reg = <0x38>;

interrupt-parent = <0x3>;

interrupts = <0x0 0x1d 0x4>;

};

};

interrupt-controller@f8f01000 {

compatible = "arm,cortex-a9-gic";

#interrupt-cells = <0x3>;

interrupt-controller;

reg = <0xf8f01000 0x1000 0xf8f00100 0x100>;

num_cpus = <0x2>;

num_interrupts = <0x60>;

linux,phandle = <0x3>;

phandle = <0x3>;

};

cache-controller@f8f02000 {

compatible = "arm,pl310-cache";

reg = <0xf8f02000 0x1000>;

interrupts = <0x0 0x2 0x4>;

arm,data-latency = <0x3 0x2 0x2>;

arm,tag-latency = <0x2 0x2 0x2>;

cache-unified;

cache-level = <0x2>;

};

memory-controller@f8006000 {

compatible = "xlnx,zynq-ddrc-a05", "xlnx,zynq-ddrc-1.0";

reg = <0xf8006000 0x1000>;

};

ocmc@f800c000 {

compatible = "xlnx,zynq-ocmc-1.0";

interrupt-parent = <0x3>;

interrupts = <0x0 0x3 0x4>;

reg = <0xf800c000 0x1000>;

};

serial@e0000000 {

compatible = "xlnx,xuartps", "cdns,uart-r1p8";

status = "disabled";

clocks = <0x1 0x17 0x1 0x28>;

clock-names = "uart_clk", "pclk";

reg = <0xe0000000 0x1000>;

interrupts = <0x0 0x1b 0x4>;

};

serial@e0001000 {

compatible = "xlnx,xuartps", "cdns,uart-r1p8";

status = "okay";

clocks = <0x1 0x18 0x1 0x29>;

clock-names = "uart_clk", "pclk";

reg = <0xe0001000 0x1000>;

interrupts = <0x0 0x32 0x4>;

current-speed = <0x1c200>;

device_type = "serial";

port-number = <0x0>;

};

spi@e0006000 {

compatible = "xlnx,zynq-spi-r1p6";

reg = <0xe0006000 0x1000>;

status = "disabled";

interrupt-parent = <0x3>;

interrupts = <0x0 0x1a 0x4>;

clocks = <0x1 0x19 0x1 0x22>;

clock-names = "ref_clk", "pclk";

#address-cells = <0x1>;

#size-cells = <0x0>;

};

spi@e0007000 {

compatible = "xlnx,zynq-spi-r1p6";

reg = <0xe0007000 0x1000>;

status = "disabled";

interrupt-parent = <0x3>;

interrupts = <0x0 0x31 0x4>;

clocks = <0x1 0x1a 0x1 0x23>;

clock-names = "ref_clk", "pclk";

#address-cells = <0x1>;

#size-cells = <0x0>;

};

spi@e000d000 {

clock-names = "ref_clk", "pclk";

clocks = <0x1 0xa 0x1 0x2b>;

compatible = "xlnx,zynq-qspi-1.0";

status = "okay";

interrupt-parent = <0x3>;

interrupts = <0x0 0x13 0x4>;

reg = <0xe000d000 0x1000>;

#address-cells = <0x1>;

#size-cells = <0x0>;

is-dual = <0x0>;

num-cs = <0x1>;

flash@0 {

compatible = "micron,m25p80", "w25q256";

reg = <0x0>;

#address-cells = <0x1>;

#size-cells = <0x1>;

spi-max-frequency = <0x2faf080>;

partition@0x00000000 {

label = "boot";

reg = <0x0 0x500000>;

};

partition@0x00500000 {

label = "bootenv";

reg = <0x500000 0x20000>;

};

partition@0x00520000 {

label = "kernel";

reg = <0x520000 0xa80000>;

};

partition@0x00fa0000 {

label = "spare";

reg = <0xfa0000 0x0>;

};

};

};

memory-controller@e000e000 {

#address-cells = <0x1>;

#size-cells = <0x1>;

status = "disabled";

clock-names = "memclk", "aclk";

clocks = <0x1 0xb 0x1 0x2c>;

compatible = "arm,pl353-smc-r2p1";

interrupt-parent = <0x3>;

interrupts = <0x0 0x12 0x4>;

ranges;

reg = <0xe000e000 0x1000>;

flash@e1000000 {

status = "disabled";

compatible = "arm,pl353-nand-r2p1";

reg = <0xe1000000 0x1000000>;

#address-cells = <0x1>;

#size-cells = <0x1>;

};

flash@e2000000 {

status = "disabled";

compatible = "cfi-flash";

reg = <0xe2000000 0x2000000>;

#address-cells = <0x1>;

#size-cells = <0x1>;

};

};

ethernet@e000b000 {

compatible = "cdns,gem";

reg = <0xe000b000 0x1000>;

status = "okay";

interrupts = <0x0 0x16 0x4>;

clocks = <0x1 0x1e 0x1 0x1e 0x1 0xd>;

clock-names = "pclk", "hclk", "tx_clk";

#address-cells = <0x1>;

#size-cells = <0x0>;

phy-mode = "rgmii-id";

xlnx,ptp-enet-clock = <0x6750918>;

local-mac-address = [00 0a 35 00 1e 53];

phy-handle = <0x4>;

mdio {

#address-cells = <0x1>;

#size-cells = <0x0>;

phy@1 {

compatible = "realtek,RTL8211E";

device_type = "ethernet-phy";

reg = <0x1>;

linux,phandle = <0x4>;

phandle = <0x4>;

};

};

};

ethernet@e000c000 {

compatible = "cdns,gem";

reg = <0xe000c000 0x1000>;

status = "disabled";

interrupts = <0x0 0x2d 0x4>;

clocks = <0x1 0x1f 0x1 0x1f 0x1 0xe>;

clock-names = "pclk", "hclk", "tx_clk";

#address-cells = <0x1>;

#size-cells = <0x0>;

};

sdhci@e0100000 {

compatible = "arasan,sdhci-8.9a";

status = "okay";

clock-names = "clk_xin", "clk_ahb";

clocks = <0x1 0x15 0x1 0x20>;

interrupt-parent = <0x3>;

interrupts = <0x0 0x18 0x4>;

reg = <0xe0100000 0x1000>;

xlnx,has-cd = <0x1>;

xlnx,has-power = <0x0>;

xlnx,has-wp = <0x1>;

};

sdhci@e0101000 {

compatible = "arasan,sdhci-8.9a";

status = "disabled";

clock-names = "clk_xin", "clk_ahb";

clocks = <0x1 0x16 0x1 0x21>;

interrupt-parent = <0x3>;

interrupts = <0x0 0x2f 0x4>;

reg = <0xe0101000 0x1000>;

};

slcr@f8000000 {

#address-cells = <0x1>;

#size-cells = <0x1>;

compatible = "xlnx,zynq-slcr", "syscon", "simple-bus";

reg = <0xf8000000 0x1000>;

ranges;

linux,phandle = <0x5>;

phandle = <0x5>;

clkc@100 {

#clock-cells = <0x1>;

compatible = "xlnx,ps7-clkc";

fclk-enable = <0x3>;

clock-output-names = "armpll", "ddrpll", "iopll", "cpu_6or4x", "cpu_3or2x", "cpu_2x", "cpu_1x", "ddr2x", "ddr3x", "dci", "lqspi", "smc", "pcap", "gem0", "gem1", "fclk0", "fclk1", "fclk2", "fclk3", "can0", "can1", "sdio0", "sdio1", "uart0", "uart1", "spi0", "spi1", "dma", "usb0_aper", "usb1_aper", "gem0_aper", "gem1_aper", "sdio0_aper", "sdio1_aper", "spi0_aper", "spi1_aper", "can0_aper", "can1_aper", "i2c0_aper", "i2c1_aper", "uart0_aper", "uart1_aper", "gpio_aper", "lqspi_aper", "smc_aper", "swdt", "dbg_trc", "dbg_apb";

reg = <0x100 0x100>;

ps-clk-frequency = <33333333>;

linux,phandle = <0x1>;

phandle = <0x1>;

};

pinctrl@700 {

compatible = "xlnx,pinctrl-zynq";

reg = <0x700 0x200>;

syscon = <0x5>;

};

};

dmac_s: dmac@f8003000 {

compatible = "arm,pl330", "arm,primecell";

reg = <0xf8003000 0x1000>;

interrupt-parent = <0x3>;

interrupt-names = "abort", "dma0", "dma1", "dma2", "dma3", "dma4", "dma5", "dma6", "dma7";

interrupts = <0x0 0xd 0x4 0x0 0xe 0x4 0x0 0xf 0x4 0x0 0x10 0x4 0x0 0x11 0x4 0x0 0x28 0x4 0x0 0x29 0x4 0x0 0x2a 0x4 0x0 0x2b 0x4>;

#dma-cells = <0x1>;

#dma-channels = <0x8>;

#dma-requests = <0x4>;

clocks = <0x1 0x1b>;

clock-names = "apb_pclk";

};

devcfg@f8007000 {

clock-names = "ref_clk", "fclk0", "fclk1", "fclk2", "fclk3";

clocks = <0x1 0xc 0x1 0xf 0x1 0x10 0x1 0x11 0x1 0x12>;

compatible = "xlnx,zynq-devcfg-1.0";

interrupt-parent = <0x3>;

interrupts = <0x0 0x8 0x4>;

reg = <0xf8007000 0x100>;

syscon = <0x5>;

};

timer@f8f00200 {

compatible = "arm,cortex-a9-global-timer";

reg = <0xf8f00200 0x20>;

interrupts = <0x1 0xb 0x301>;

interrupt-parent = <0x3>;

clocks = <0x1 0x4>;

};

timer@f8001000 {

interrupt-parent = <0x3>;

interrupts = <0x0 0xa 0x4 0x0 0xb 0x4 0x0 0xc 0x4>;

compatible = "cdns,ttc";

clocks = <0x1 0x6>;

reg = <0xf8001000 0x1000>;

};

timer@f8002000 {

interrupt-parent = <0x3>;

interrupts = <0x0 0x25 0x4 0x0 0x26 0x4 0x0 0x27 0x4>;

compatible = "cdns,ttc";

clocks = <0x1 0x6>;

reg = <0xf8002000 0x1000>;

};

timer@f8f00600 {

interrupt-parent = <0x3>;

interrupts = <0x1 0xd 0x301>;

compatible = "arm,cortex-a9-twd-timer";

reg = <0xf8f00600 0x20>;

clocks = <0x1 0x4>;

};

usb@e0002000 {

compatible = "xlnx,zynq-usb-2.20a", "chipidea,usb2";

status = "okay";

clocks = <0x1 0x1c>;

interrupt-parent = <0x3>;

interrupts = <0x0 0x15 0x4>;

reg = <0xe0002000 0x1000>;

phy_type = "ulpi";

dr_mode = "host";

usb-reset = <0x6 0x2e 0x0>;

usb-phy = <0x7>;

};

usb@e0003000 {

compatible = "xlnx,zynq-usb-2.20a", "chipidea,usb2";

status = "disabled";

clocks = <0x1 0x1d>;

interrupt-parent = <0x3>;

interrupts = <0x0 0x2c 0x4>;

reg = <0xe0003000 0x1000>;

phy_type = "ulpi";

};

watchdog@f8005000 {

clocks = <0x1 0x2d>;

compatible = "cdns,wdt-r1p2";

interrupt-parent = <0x3>;

interrupts = <0x0 0x9 0x1>;

reg = <0xf8005000 0x1000>;

timeout-sec = <0xa>;

};

};

amba_pl {

#address-cells = <0x1>;

#size-cells = <0x1>;

compatible = "simple-bus";

ranges;

gpio_btns@41220000 {

#gpio-cells = <0x2>;

compatible = "xlnx,xps-gpio-1.00.a";

gpio-controller;

reg = <0x41220000 0x10000>;

xlnx,all-inputs = <0x1>;

xlnx,all-inputs-2 = <0x0>;

xlnx,all-outputs = <0x0>;

xlnx,all-outputs-2 = <0x0>;

xlnx,dout-default = <0x0>;

xlnx,dout-default-2 = <0x0>;

xlnx,gpio-width = <0x4>;

xlnx,gpio2-width = <0x20>;

xlnx,interrupt-present = <0x0>;

xlnx,is-dual = <0x0>;

xlnx,tri-default = <0xffffffff>;

xlnx,tri-default-2 = <0xffffffff>;

};

gpio_leds@41210000 {

#gpio-cells = <0x2>;

compatible = "xlnx,xps-gpio-1.00.a";

gpio-controller;

reg = <0x41210000 0x10000>;

xlnx,all-inputs = <0x0>;

xlnx,all-inputs-2 = <0x0>;

xlnx,all-outputs = <0x1>;

xlnx,all-outputs-2 = <0x0>;

xlnx,dout-default = <0x0>;

xlnx,dout-default-2 = <0x0>;

xlnx,gpio-width = <0x4>;

xlnx,gpio2-width = <0x20>;

xlnx,interrupt-present = <0x0>;

xlnx,is-dual = <0x0>;

xlnx,tri-default = <0xffffffff>;

xlnx,tri-default-2 = <0xffffffff>;

};

dma@43000000 {

#dma-cells = <0x1>;

compatible = "xlnx,axi-vdma-1.00.a";

reg = <0x43000000 0x10000>;

//xlnx,flush-fsync = <0x1>;

xlnx,num-fstores = <0x1>;

linux,phandle = <0xc>;

phandle = <0xc>;

dma-channel@43000000 {

compatible = "xlnx,axi-vdma-mm2s-channel";

interrupt-parent = <0x3>;

interrupts = <0x0 0x1e 0x4>;

clocks = <0x1 0x10>;

clock-names = "axis";

xlnx,datawidth = <0x20>;

xlnx,device-id = <0x0>;

};

};

v_tc@43c00000 {

compatible = "xlnx,v-tc-5.01.a";

interrupt-parent = <0x3>;

interrupts = <0x0 0x1f 0x4>;

reg = <0x43c00000 0x10000>;

xlnx,det-achroma-en = <0x0>;

xlnx,det-avideo-en = <0x1>;

xlnx,det-fieldid-en = <0x0>;

xlnx,det-hblank-en = <0x1>;

xlnx,det-hsync-en = <0x1>;

xlnx,det-vblank-en = <0x1>;

xlnx,det-vsync-en = <0x1>;

xlnx,detect-en = <0x0>;

xlnx,fsync-hstart0 = <0x0>;

xlnx,fsync-hstart1 = <0x0>;

xlnx,fsync-hstart10 = <0x0>;

xlnx,fsync-hstart11 = <0x0>;

xlnx,fsync-hstart12 = <0x0>;

xlnx,fsync-hstart13 = <0x0>;

xlnx,fsync-hstart14 = <0x0>;

xlnx,fsync-hstart15 = <0x0>;

xlnx,fsync-hstart2 = <0x0>;

xlnx,fsync-hstart3 = <0x0>;

xlnx,fsync-hstart4 = <0x0>;

xlnx,fsync-hstart5 = <0x0>;

xlnx,fsync-hstart6 = <0x0>;

xlnx,fsync-hstart7 = <0x0>;

xlnx,fsync-hstart8 = <0x0>;

xlnx,fsync-hstart9 = <0x0>;

xlnx,fsync-vstart0 = <0x0>;

xlnx,fsync-vstart1 = <0x0>;

xlnx,fsync-vstart10 = <0x0>;

xlnx,fsync-vstart11 = <0x0>;

xlnx,fsync-vstart12 = <0x0>;

xlnx,fsync-vstart13 = <0x0>;

xlnx,fsync-vstart14 = <0x0>;

xlnx,fsync-vstart15 = <0x0>;

xlnx,fsync-vstart2 = <0x0>;

xlnx,fsync-vstart3 = <0x0>;

xlnx,fsync-vstart4 = <0x0>;

xlnx,fsync-vstart5 = <0x0>;

xlnx,fsync-vstart6 = <0x0>;

xlnx,fsync-vstart7 = <0x0>;

xlnx,fsync-vstart8 = <0x0>;

xlnx,fsync-vstart9 = <0x0>;

xlnx,gen-achroma-en = <0x0>;

xlnx,gen-achroma-polarity = <0x1>;

xlnx,gen-auto-switch = <0x0>;

xlnx,gen-avideo-en = <0x1>;

xlnx,gen-avideo-polarity = <0x1>;

xlnx,gen-cparity = <0x0>;

xlnx,gen-f0-vblank-hend = <0x500>;

xlnx,gen-f0-vblank-hstart = <0x500>;

xlnx,gen-f0-vframe-size = <0x2ee>;

xlnx,gen-f0-vsync-hend = <0x500>;

xlnx,gen-f0-vsync-hstart = <0x500>;

xlnx,gen-f0-vsync-vend = <0x2d9>;

xlnx,gen-f0-vsync-vstart = <0x2d4>;

xlnx,gen-f1-vblank-hend = <0x500>;

xlnx,gen-f1-vblank-hstart = <0x500>;

xlnx,gen-f1-vframe-size = <0x2ee>;

xlnx,gen-f1-vsync-hend = <0x500>;

xlnx,gen-f1-vsync-hstart = <0x500>;

xlnx,gen-f1-vsync-vend = <0x2d9>;

xlnx,gen-f1-vsync-vstart = <0x2d4>;

xlnx,gen-fieldid-en = <0x0>;

xlnx,gen-fieldid-polarity = <0x1>;

xlnx,gen-hactive-size = <0x500>;

xlnx,gen-hblank-en = <0x1>;

xlnx,gen-hblank-polarity = <0x1>;

xlnx,gen-hframe-size = <0x672>;

xlnx,gen-hsync-en = <0x1>;

xlnx,gen-hsync-end = <0x596>;

xlnx,gen-hsync-polarity = <0x1>;

xlnx,gen-hsync-start = <0x56e>;

xlnx,gen-interlaced = <0x0>;

xlnx,gen-vactive-size = <0x2d0>;

xlnx,gen-vblank-en = <0x1>;

xlnx,gen-vblank-polarity = <0x1>;

xlnx,gen-video-format = <0x2>;

xlnx,gen-vsync-en = <0x1>;

xlnx,gen-vsync-polarity = <0x1>;

xlnx,generate-en = <0x1>;

xlnx,has-axi4-lite = <0x1>;

xlnx,has-intc-if = <0x0>;

xlnx,interlace-en = <0x0>;

xlnx,max-lines = <0x1000>;

xlnx,max-pixels = <0x1000>;

xlnx,num-fsyncs = <0x1>;

xlnx,sync-en = <0x0>;

linux,phandle = <0x9>;

phandle = <0x9>;

};

axi_dynclk@43c10000 {

compatible = "digilent,axi-dynclk";

#clock-cells = <0x0>;

reg = <0x43c10000 0x10000>;

xlnx,s00-axi-addr-width = <0x5>;

xlnx,s00-axi-data-width = <0x20>;

clocks = <0x1 0xf>;

linux,phandle = <0xb>;

phandle = <0xb>;

};

xilinx_drm {

compatible = "xlnx,drm";

xlnx,vtc = <0x9>;

xlnx,connector-type = "HDMIA";

xlnx,encoder-slave = <0xa>;

clocks = <0xb>;

dglnt,edid-i2c = <0x8>;

planes {

xlnx,pixel-format = "xrgb8888";

plane0 {

dmas = <0xc 0x0>;

dma-names = "dma";

};

};

};

digilent_encoder {

compatible = "dglnt,drm-encoder";

dglnt,edid-i2c = <0x8>;

linux,phandle = <0xa>;

phandle = <0xa>;

};

};

usb_phy@0 {

compatible = "usb-nop-xceiv";

#phy-cells = <0x0>;

reset-gpios = <0x6 46 0x1>;

linux,phandle = <0x7>;

phandle = <0x7>;

};

uio@0{

compatible="generic-uio";

status="okay";

interrupt-controller;

interrupt-parent=<0x4>;

interrupts=<0x0 0x1d 0x1>;

};

uio@1{

compatible="generic-uio";

status="okay";

interrupt-controller;

interrupt-parent=<0x4>;

interrupts=<0x0 0x1f 0x1>;

};

uio@2{

compatible="generic-uio";

status="okay";

interrupt-controller;

interrupt-parent=<0x4>;

interrupts=<0x0 0x20 0x1>;

};

uio@3{

compatible="generic-uio";

status="okay";

interrupt-controller;

interrupt-parent=<0x4>;

interrupts=<0x0 0x21 0x1>;

};

};

3.2.3 修改 linux kernel

修改linux 内核，增加 linux 对于uio模型的支持。

make menuconfig ARCH=arm CROSS_COMPILE=arm-xilinx-linux-gnueabi-

在配置菜单中 Device Drivers —> Userspace I/O drivers ，配置如图3-1所示，选中 uio 的2个配置。

3.2.4 编译内核和设备树

编译内核make ARCH=arm CROSS_COMPILE=arm-xilinx-linux-gnueabi- uImage LOADADDR=0x00008000

编译设备树./scripts/dtc/dtc -I dts -O dtb -o devicetree.dtb ./arch/arm/boot/dts/AX7010.dts

4 UIO 模型源码分析和测试代码

4.1 uio 模型说明

需要注意的一个问题，uio 模型，在内核层，一收到中断，则立马 disable 中断，这点详见内核代码linux4.0/drivers/uio/uio_pdrv_genirq.c

static irqreturn_t uio_pdrv_genirq_handler(int irq, struct uio_info *dev_info)

{

struct uio_pdrv_genirq_platdata *priv = dev_info->priv;

/* Just disable the interrupt in the interrupt controller, and

* remember the state so we can allow user space to enable it later.

*/

spin_lock(&priv->lock);

if (!__test_and_set_bit(UIO_IRQ_DISABLED, &priv->flags))

disable_irq_nosync(irq);

spin_unlock(&priv->lock);

return IRQ_HANDLED;

}

从代码上可以看出，中断一旦触发，立马关闭中断。

然后从 linux4.0/drivers/uio/uio.c 中, 可以看到uio 中断产生后，发送了SIGIO给用户层

/**

* uio_event_notify - trigger an interrupt event

* @info: UIO device capabilities

*/

void uio_event_notify(struct uio_info *info)

{

struct uio_device *idev = info->uio_dev;

atomic_inc(&idev->event);

wake_up_interruptible(&idev->wait);

kill_fasync(&idev->async_queue, SIGIO, POLL_IN);

}

EXPORT_SYMBOL_GPL(uio_event_notify);

对于如何开启UIO 中断，则由 linux4.0/drivers/uio/uio.c 中, write 函数实现

写入0，则关闭，写入1则开启。

static ssize_t uio_write(struct file *filep, const char __user *buf,

size_t count, loff_t *ppos)

{

struct uio_listener *listener = filep->private_data;

struct uio_device *idev = listener->dev;

ssize_t retval;

s32 irq_on;

if (!idev->info->irq)

return -EIO;

if (count != sizeof(s32))

return -EINVAL;

if (!idev->info->irqcontrol)

return -ENOSYS;

if (copy_from_user(&irq_on, buf, count))

return -EFAULT;

retval = idev->info->irqcontrol(idev->info, irq_on);

return retval ? retval : sizeof(s32);

}

4.2 用户层测试程序

/*======================================================================

beeper driver APP .

All right reserved.

======================================================================*/

#include

#include

#include

#include

#include

#include

#include

#include

#include

#include

#include

#include

#include

#include

#define UIO_NAME "/dev/uio0"

int fd;

// 信号处理函数

void my_signal_fun(int signum)

{

char buf[2] = "1";

int on = 1;// uio 使能命令

int count = 4;// uio 中断驱动，必须4字节操作

printf("app get the: %s irqn", UIO_NAME);

fflush(stdout);

write(fd, &on, count);// 使能uio中断

}

int main(int argc, char *argv[])

{

unsigned char key_val;

int ret;

int Oflags;

// 在应用程序中捕捉SIGIO信号(由驱动程序发送)

signal(SIGIO, my_signal_fun);

fd = open(UIO_NAME, O_RDWR);

if (fd < 0)

{

printf("can't open file ,file name is %s!n", UIO_NAME);

}

printf("open the %s successn", UIO_NAME);

// 将当前进程PID设置为fd文件所对应驱动程序将要发送SIGIO,SIGUSR信号进程PID

fcntl(fd, F_SETOWN, getpid());

// 获取fd的打开方式

Oflags = fcntl(fd, F_GETFL);

// 将fd的打开方式设置为FASYNC --- 即 支持异步通知

// 该行代码执行会触发 驱动程序中 file_operations->fasync 函数

// ------fasync函数调用fasync_helper初始化一个fasync_struct结构体，

// 该结构体描述了将要发送信号的进程PID (fasync_struct->fa_file->f_owner->pid)

fcntl(fd, F_SETFL, Oflags | FASYNC);

while (1)

{

sleep(1000);

}

return 0;

}

编译用户层测试程序

arm-xilinx-linux-gnueabi-gcc -o uio_test uio_app.c

将程序下载到开发板上，然后运行测试

按键触发 irq_f2p 中断, 按键3次，产生3次中断，可以看得到打印信息，说明中断已经完全捕获。

./uio_test

app get the: /dev/uio0

app get the: /dev/uio0

app get the: /dev/uio0