海思3520d平台UART口拓展
项目中要把海思3520d的四个UART口全部用上，但是用海思SDK里面的linux内核的话，默认只有两个口，分别是ttyAMA0 ttyAMA1。如果要把四个UART口全部都用上就要改内核源码。听起来挺吓人的，其实就是依葫芦画瓢的事儿，没什么技术含量。下面就切入主题。
修改
1：arch/arm/mach-hi3520d/core.c
2：arch/arm/mach-hi3520d/include/mach/irqs.h
这两个文件即可，修改如下：
--- /mnt/hgfs/windows-F/Hi3520D/linux-3.0.y/arch/arm/mach-hi3520d/core.c 2013-05-15 11:44:29.000000000 +0800
+++ /root/3520d/osdrv/kernel/linux-3.0.y/arch/arm/mach-hi3520d/core.c 2014-01-13 15:38:47.000000000 +0800
@@ -309,15 +309,19 @@
HIL_AMBA_DEVICE(uart0, "uart:0", UART0, NULL);
HIL_AMBA_DEVICE(uart1, "uart:1", UART1, NULL);
+HIL_AMBA_DEVICE(uart2, "uart:2", UART2, NULL);
+HIL_AMBA_DEVICE(uart3, "uart:3", UART3, NULL);
static struct amba_device *amba_devs[] __initdata = {
&HIL_AMBADEV_NAME(uart0),
&HIL_AMBADEV_NAME(uart1),
+ &HIL_AMBADEV_NAME(uart2),
+ &HIL_AMBADEV_NAME(uart3),
};
static struct clk uart_clk;
-static struct clk_lookup lookups[2];
+static struct clk_lookup lookups[4];
static void uart_clk_init(unsigned long clk)
{
@@ -328,6 +332,12 @@
lookups[1].dev_id = "uart:1";
lookups[1].clk = &uart_clk;
+
+ lookups[2].dev_id = "uart:2";
+ lookups[2].clk = &uart_clk;
+
+ lookups[3].dev_id = "uart:3";
+ lookups[3].clk = &uart_clk;
}
void __init hi3520d_init(void)
--- /mnt/hgfs/windows-F/Hi3520D/linux-3.0.y/arch/arm/mach-hi3520d/include/mach/irqs.h 2013-05-15 11:44:29.000000000 +0800
+++ /root/3520d/osdrv/kernel/linux-3.0.y/arch/arm/mach-hi3520d/include/mach/irqs.h 2014-01-13 15:55:51.000000000 +0800
@@ -8,6 +8,8 @@
#define UART0_IRQ (HI3520D_IRQ_START + 8)
#define UART1_IRQ (HI3520D_IRQ_START + 9)
+#define UART2_IRQ (HI3520D_IRQ_START + 10)
+#define UART3_IRQ (HI3520D_IRQ_START + 11)
#define INTNR_L2CACHE_CHK0_INT (HI3520D_IRQ_START + 29)
#define INTNR_L2CACHE_CHK1_INT (HI3520D_IRQ_START + 30)
上述是用diff比较修改后与修改前的文件的结果，感觉这样子一目了然！
