文章目录
前言
由于T507这款soc中没有带can接口，而项目中需要can接口，故采用了mcp2515 spi转can进行调试。
一、设备树配置
1.1、SPI总线确认
通过原理图确认SPI总线，并把SPI总线的片选以及总线的复用情况进行整理配置
c
diff --git a/device/config/chips/t507/configs/demo2.0/board.dts b/device/config/chips/t507/configs/demo2.0/board.dts
index dd51dbc284..bf15f85f5a 100755
--- a/device/config/chips/t507/configs/demo2.0/board.dts
+++ b/device/config/chips/t507/configs/demo2.0/board.dts
@@ -83,13 +83,13 @@
};
spi1_pins_b: spi1@1 {
- allwinner,pins = "PH5", "PH9";
- allwinner,pname = "spi1_cs0", "spi1_cs1";
+ allwinner,pins = "PH5";
+ allwinner,pname = "spi1_cs0";
allwinner,function = "spi1";
};
spi1_pins_c: spi1@2 {
- allwinner,pins = "PH5", "PH6", "PH7", "PH8", "PH9";
+ allwinner,pins = "PH5", "PH6", "PH7", "PH8";
allwinner,function = "io_disabled";
};
c
diff --git a/device/config/chips/t507/configs/demo2.0/sys_config.fex b/device/config/chips/t507/configs/demo2.0/sys_config.fex
index bb583b70d6..ff3a11776a 100755
--- a/device/config/chips/t507/configs/demo2.0/sys_config.fex
+++ b/device/config/chips/t507/configs/demo2.0/sys_config.fex
@@ -132,12 +132,12 @@ uart_debug_port = 0
uart_debug_tx = port:PH00<2><1><default><default>
uart_debug_rx = port:PH01<2><1><default><default>
-[jtag_para]
-jtag_enable = 1
-jtag_ms = port:PH9<3><default><default><default>
-jtag_ck = port:PH10<3><default><default><default>
-jtag_do = port:PH11<3><default><default><default>
-jtag_di = port:PH12<3><default><default><default>
+;[jtag_para]
+;jtag_enable = 1
+;jtag_ms = port:PH9<3><default><default><default>
+;jtag_ck = port:PH10<3><default><default><default>
+;jtag_do = port:PH11<3><default><default><default>
+;jtag_di = port:PH12<3><default><default><default>1.2、DTS配置
对mcp2515进行配置，clk信号以及中断等处理，同时在项目中如果有3.3v转5v的电平转换芯片，需要确保改转换ic的工作正常。
c
diff --git a/kernel/linux-4.9/arch/arm64/boot/dts/sunxi/sun50iw9p1-clk.dtsi b/kernel/linux-4.9/arch/arm64/boot/dts/sunxi/sun50iw9p1-clk.dtsi
index 7708d3083b..6466bfe206 100755
--- a/kernel/linux-4.9/arch/arm64/boot/dts/sunxi/sun50iw9p1-clk.dtsi
+++ b/kernel/linux-4.9/arch/arm64/boot/dts/sunxi/sun50iw9p1-clk.dtsi
@@ -10,6 +10,13 @@ clocks {
<0x0 0x07000000 0x0 0x4>;
/* register fixed rate clock*/
+ mcp251x_clk: mcp251x_clk{
+ #clock-cells = <0>;
+ compatible = "allwinner,fixed-clock";
+ clock-frequency = <8000000>;
+ clock-output-names = "mcp251x_clk";
+ };
+
clk_losc: losc {
#clock-cells = <0>;
compatible = "allwinner,fixed-clock";
c
diff --git a/device/config/chips/t507/configs/demo2.0/board.dts b/device/config/chips/t507/configs/demo2.0/board.dts
index dd51dbc284..bf15f85f5a 100755
--- a/device/config/chips/t507/configs/demo2.0/board.dts
+++ b/device/config/chips/t507/configs/demo2.0/board.dts
@@ -273,6 +273,15 @@
allwinner,drive = <1>;
allwinner,pull = <0>;
};
+
+ can_irq: can0@0 {
+ allwinner,pins = "PH9";
+ allwinner,pname = "can_irq";
+ allwinner,function = "irq";
+ allwinner,muxsel = <6>;
+ allwinner,drive = <1>;
+ allwinner,pull = <0>;
+ };
};
@@ -293,7 +302,8 @@
spi1: spi@05011000 {
pinctrl-0 = <&spi1_pins_a &spi1_pins_b>;
pinctrl-1 = <&spi1_pins_c>;
spi_slave_mode = <0>;
- status = "disabled";
+ status = "okay";
+ mcp2515{
+ status = "okay";
+ reg = <0x0>;
+ compatible = "microchip,mcp2515";
+ spi-max-frequency = <24000000>;
+ clocks = <&mcp251x_clk>;
+ interrupt-parent = <&pio>;
+ interrupts = <PH 9 IRQ_TYPE_EDGE_BOTH>;
+ pinctrl-names = "default";
+ pinctrl-0 = <&can_irq>;
+ };
}; 二、驱动配置
2.1、驱动位置
定为驱动，使用内核中的驱动即可，包括mcp2515驱动，spi总线以及can网络配置
mcp2515驱动：
c
kernel/linux-4.9/drivers/net/can/spi/mcp251x.cspi总线：
c
kernel/linux-4.9/drivers/spican网络：
c
kernel/linux-4.9/drivers/net/can使用宏来配置驱动。
2.2、使用config宏配置驱动
c
diff --git a/kernel/linux-4.9/arch/arm64/configs/sun50iw9p1smp_longan_defconfig b/kernel/linux-4.9/arch/arm64/configs/sun50iw9p1smp_longan_defconfig
index d9b09b74ab..9ec92f7774 100755
--- a/kernel/linux-4.9/arch/arm64/configs/sun50iw9p1smp_longan_defconfig
+++ b/kernel/linux-4.9/arch/arm64/configs/sun50iw9p1smp_longan_defconfig
@@ -1038,7 +1038,11 @@ CONFIG_NET_FLOW_LIMIT=y
# CONFIG_NET_PKTGEN is not set
# CONFIG_NET_DROP_MONITOR is not set
# CONFIG_HAMRADIO is not set
-# CONFIG_CAN is not set
+CONFIG_CAN=y
+CONFIG_CAN_RAW=y
+CONFIG_CAN_BCM=y
+CONFIG_CAN_GW=y
+CONFIG_CAN_MCP251X=y
# CONFIG_IRDA is not set
CONFIG_BT=y
CONFIG_BT_BREDR=y
@@ -1382,7 +1386,7 @@ CONFIG_TUN=y
CONFIG_ETHERNET=y
CONFIG_NET_VENDOR_ALLWINNER=y
# CONFIG_SUN4I_EMAC is not set
-# CONFIG_SUNXI_GMAC is not set
+CONFIG_SUNXI_GMAC=y
# CONFIG_ALTERA_TSE is not set
CONFIG_NET_VENDOR_AMAZON=y
CONFIG_NET_VENDOR_AMD=y
@@ -1912,7 +1916,10 @@ CONFIG_I2C_SUNXI=y
# CONFIG_I2C_DEBUG_CORE is not set
# CONFIG_I2C_DEBUG_ALGO is not set
# CONFIG_I2C_DEBUG_BUS is not set
-# CONFIG_SPI is not set
+CONFIG_SPI=y
+CONFIG_SPI_MASTER=y
+CONFIG_SPI_SPIDEV=y
+CONFIG_SPI_SUNXI=y
# CONFIG_SPMI is not set
# CONFIG_HSI is not set2.3、MCP2515驱动调试中遇到的问题
2.3.1、问题描述
调试mcp2515 spi转can过程中，软件写复位读出来的状态是0x01复位不了mcp2515
2.3.2、分析问题
软件复位中，spi的写操作过快，没有将mcp2515寄存器进行复位完成
2.3.3、处理问题
在软复位中，添加timer处理
c
diff --git a/kernel/linux-4.9/drivers/net/can/spi/mcp251x.c b/kernel/linux-4.9/drivers/net/can/spi/mcp251x.c
index f3f05fea8e..82169895a0 100755
--- a/kernel/linux-4.9/drivers/net/can/spi/mcp251x.c
+++ b/kernel/linux-4.9/drivers/net/can/spi/mcp251x.c
@@ -627,7 +627,7 @@ static int mcp251x_setup(struct net_device *net, struct mcp251x_priv *priv,
static int mcp251x_hw_reset(struct spi_device *spi)
{
struct mcp251x_priv *priv = spi_get_drvdata(spi);
- u8 reg;
+ unsigned long timeout;
int ret;
/* Wait for oscillator startup timer after power up */
@@ -638,13 +638,14 @@ static int mcp251x_hw_reset(struct spi_device *spi)
if (ret)
return ret;
- /* Wait for oscillator startup timer after reset */
- mdelay(MCP251X_OST_DELAY_MS);
-
- reg = mcp251x_read_reg(spi, CANSTAT);
- if ((reg & CANCTRL_REQOP_MASK) != CANCTRL_REQOP_CONF)
- return -ENODEV;
-
+ timeout = jiffies + HZ;
+ while ((mcp251x_read_reg(spi, CANSTAT) & CANCTRL_REQOP_MASK) != CANCTRL_REQOP_CONF) {
+ usleep_range(MCP251X_OST_DELAY_MS * 1000,MCP251X_OST_DELAY_MS * 1000 * 2);
+ if (time_after(jiffies, timeout)) {
+ printk("MCP251x didn't enter in conf mode after reset\n");
+ return -EBUSY;
+ }
+ }
return 0;
}三、buildroot 集成can测试工具
sdk的buildroot中can测试工具是没有的，需要自行进行添加，同时需要将out目录下的.config删除
.config：
c
out/t507/demo2.0/longan/buildroot/.config集成can测试工具
c
diff --git a/buildroot/buildroot-201902/configs/sun50iw9p1_longan_defconfig b/buildroot/buildroot-201902/configs/sun50iw9p1_longan_defconfig
index 8cafd7e907..3b3c8b1f28 100755
--- a/buildroot/buildroot-201902/configs/sun50iw9p1_longan_defconfig
+++ b/buildroot/buildroot-201902/configs/sun50iw9p1_longan_defconfig
@@ -1943,7 +1943,7 @@ BR2_PACKAGE_QEMU_ARCH_SUPPORTS_TARGET=y
# BR2_PACKAGE_BRIDGE_UTILS is not set
# BR2_PACKAGE_BWM_NG is not set
# BR2_PACKAGE_C_ICAP is not set
-# BR2_PACKAGE_CAN_UTILS is not set
+BR2_PACKAGE_CAN_UTILS=y
# BR2_PACKAGE_CANNELLONI is not set
# BR2_PACKAGE_CHRONY is not set
# BR2_PACKAGE_CIVETWEB is not set
@@ -2024,7 +2024,7 @@ BR2_PACKAGE_HOSTAPD_VLAN_NETLINK=y
# BR2_PACKAGE_IODINE is not set
# BR2_PACKAGE_IPERF is not set
# BR2_PACKAGE_IPERF3 is not set
-# BR2_PACKAGE_IPROUTE2 is not set
+BR2_PACKAGE_IPROUTE2=y
# BR2_PACKAGE_IPSEC_TOOLS is not set
# BR2_PACKAGE_IPSET is not set
# BR2_PACKAGE_IPTABLES is not set四、测试
c
ip link set can0 down #关闭can设备；
ip link set can0 up type can bitrate 250000 #设置can波特率
ip link set can0 up #开启can设备
cansend can0 123#000102030405060708 #发送信息
candump can0 #接收can总线发来数据
ip -details link show can0 #显示can设备详细信息
ifconfig can0 down #关闭can设备，以便配置