上面电路图部分。GPMC_D1 ------GPMC_D7 以及GPMC_WEn和REn都被NAND复用了，所以在board_am335xevm.c板级文件里面，这些引脚我没有动它，并且在static struct pinmux_config nand_pin_mux[] 里面添加了
{"gpmc_csn1.gpmc_csn1", OMAP_MUX_MODE0 | AM33XX_PULL_DISA},
{"gpmc_csn2.gpmc_csn2", OMAP_MUX_MODE0 | AM33XX_PULL_ENBL},
板级文件里面添加以下内容:
static struct gpmc_timings am335x_led_timings = {
.sync_clk = 0,
.cs_on = 0, /* Assertion time */
.cs_rd_off = 82,/* Read deassertion time */
.cs_wr_off = 82,/* Write deassertion time */
// .we_on = 40, /* WE assertion time */
.we_on = 10,
.we_off = 40, /* WE deassertion time */
// .oe_on = 40, /* OE assertion time */
.oe_on = 10,
.oe_off = 40, /* OE deassertion time */
.access = 64, /* Start-cycle to first data valid delay */
.rd_cycle = 82, /* Total read cycle time */
.wr_cycle = 82, /* Total write cycle time */
};
static struct am335x_led_platform_data am335x_led_data = {
.cs = 1,
.gpmc_t = &am335x_led_timings,
.devsize = 8,
.elm_used = true,
.memsize =SZ_16M,
};
static struct resource gpmc_lcd_8080_resource = {
.flags = IORESOURCE_MEM,
};
static struct platform_device am335x_lcd_8080_device = {
.name = "lcd_8080",
.id = -1,
.num_resources = 1,
.resource = &gpmc_lcd_8080_resource,
.dev = {
.platform_data = &am335x_led_data,
},
};
//初始化：
static void __init am335x_lcd_8080_init(void)
{
int ret;
printk("___am335x_lcd_8080_init\n");
//struct am335x_led_platform_data *pdata;
setup_pin_mux(led_pin_mux);
platform_device_register(&am335x_lcd_8080_device);
#if 1
ret = gpio_request(LED_RST, "LED_RST");
if(ret < 0)
printk("Failed to request GPIO: %d!\n", LED_RST);
else
{
gpio_direction_output(LED_RST,0);
msleep(10);
gpio_direction_output(LED_RST,1);
}
#endif
参考网上资料，附件包含着驱动程序。
}
运行驱动之后，能正常的写，但是片选就是偏选不上。
下面是执行驱动之后的对应的打印信息。
[ 42.313034] Disabling lock debugging due to kernel taint
[ 42.319626] lcd_8080_probe>>>>>>>>
[ 42.323225] gmpc_base>>>>>>>>==e0876000
[ 42.327422] ppdata->cs===1
[ 42.330284] ppdata->devsize==8
[ 42.333468] ppdata->memsize===1000000
[ 42.337287] Getting Chip Select
[ 42.340575] GPMC revision 6.0
[ 42.343679] GPMC CS1: cs_on : 0 ticks, 0 ns (was 1 ticks) 0 ns
[ 42.351010] GPMC CS1: cs_rd_off : 9 ticks, 90 ns (was 16 ticks) 82 ns
[ 42.358279] GPMC CS1: cs_wr_off : 9 ticks, 90 ns (was 16 ticks) 82 ns
[ 42.365461] GPMC CS1: adv_on : 0 ticks, 0 ns (was 4 ticks) 0 ns
[ 42.372654] GPMC CS1: adv_rd_off: 0 ticks, 0 ns (was 5 ticks) 0 ns
[ 42.379841] GPMC CS1: adv_wr_off: 0 ticks, 0 ns (was 6 ticks) 0 ns
[ 42.387023] GPMC CS1: oe_on : 1 ticks, 10 ns (was 6 ticks) 10 ns
[ 42.394221] GPMC CS1: oe_off : 4 ticks, 40 ns (was 16 ticks) 40 ns
[ 42.401411] GPMC CS1: we_on : 1 ticks, 10 ns (was 5 ticks) 10 ns
[ 42.408623] GPMC CS1: we_off : 4 ticks, 40 ns (was 16 ticks) 40 ns
[ 42.415801] GPMC CS1: rd_cycle : 9 ticks, 90 ns (was 17 ticks) 82 ns
[ 42.423004] GPMC CS1: wr_cycle : 9 ticks, 90 ns (was 17 ticks) 82 ns
[ 42.430189] GPMC CS1: access : 7 ticks, 70 ns (was 15 ticks) 64 ns
[ 42.437367] GPMC CS1: page_burst_access: 0 ticks, 0 ns (was 1 ticks) 0 ns
[ 42.445185] GPMC CS1: wr_data_mux_bus: 0 ticks, 0 ns (was 7 ticks) 0 ns
[ 42.452825] GPMC CS1: wr_access : 0 ticks, 0 ns (was 15 ticks) 0 ns
[ 42.460009] GPMC CS1 CLK period is 10 ns (div 1)
[ 42.464823] gpmc_cs_request......................
[ 42.469739] size>>>>1000000
[ 42.472649] res->start>>>>>>0
[ 42.475737] gpmc->mem_root>>>>100000
[ 42.479486] Got CS1, address = 1000000
[ 42.483398] data_req start: 0x1000000 size: 0x1000000
[ 42.489139] >>>>>pdata->io_base==0xe1000000
[ 42.493503] gpmc cs0 reg: 0x800
[ 42.496776] gpmc cs0 reg: 0x50500
[ 42.500238] gpmc cs0 reg: 0x50401
[ 42.503690] gpmc cs0 reg: 0x4010601
[ 42.507325] gpmc cs0 reg: 0x70909
[ 42.510791] gpmc cs0 reg: 0x4000f80
[ 42.514426] gpmc cs0 reg: 0xf48
[ 42.517706]
[ 42.519255] gpmc cs1 reg: 0x28600200
[ 42.522989] gpmc cs1 reg: 0x90900
[ 42.526440] gpmc cs1 reg: 0x22000010
[ 42.530173] gpmc cs1 reg: 0x4016411
[ 42.533806] gpmc cs1 reg: 0x70909
[ 42.537262] gpmc cs1 reg: 0x80000000
[ 42.540996] gpmc cs1 reg: 0xf41
[ 42.544267]
[ 42.545820] gpmc cs1, base: 0x1000000, size: 0x1000000
[ 42.551188] base>>>>>>1000000
[ 42.554279] size======1000000
[ 42.557366] ASASASASASASASA
片选0是nand flash，片选1是ra8806单色屏我想直接往写数据进去，但是测试的结果就是片选1没有信号。一直处于高电平状态。为什么是什么反应都没有，百思不得其解，求各位大神多多帮忙。
