Toggling GPMC_AD12 high and low

Hello Siddarth,

At first, could you explain us more about your hardware and software platforms with OMAP4?

As I can understand from your question: You want to configure GPMC_AD12 pad as GPIO. Am I right?

To configure GPMC_AD12 as GPIO_36, you must change muxmode settings of this pad. In other words you must set 0x3 value in bit-field of  CONTROL_CORE_PAD0_GPMC_AD12_PAD1_GPMC_AD13[2:0] GPMC_AD12_MUXMODE
Functional multiplexing selection for pad gpmc_ad12
0x0: Select gpmc_ad12
0x1: Select kpd_col0
0x2: Select c2c_data11
0x3: Select gpio_36
0x5: Select sdmmc1_dat4

Best regards,

Yanko

Hi Yanko,

Sorry for delay.

And thanks for the reply. After reviewing your answer I studied T.R.M of omap4460 section 25 for GPIO and done the following things to configure gpio_36 high or low

1. Configured the appropriate pad-mux register as 0x3 with physical address as 0x4A100058 as mentioned in T.R.M of omap4460 as __raw_writew(0x3,0x4A100058);
2. Enabled the GPIO module: after going through T.R.M I found that gpio_36 lies under gpio module 2 and also gpio_36 is the fifth GPIO of GPIO2 module. (Kindly confirm it). and to enable GPIO module 2 I had set the modulemode field in the register CM_L4PER_GPIO2_CLKCTRL with physical address 0x4A009460 using __raw_writel(0x5,0x4A009460);
3. Set the GPIO as an output: by setting GPIO_OE register __raw_writel(0x5,0x48055134);
4. Now toggled the GPIO by setting/clearing the appropriate bit in GPIO_DATAOUT

                u32 val;

 val = __raw_readl(0x4805513c);

__raw_writel((val | 0x1),0x4805513c)

__raw_writel((val & ~0x1),0x4805513c);

Now could you let me know whether I am going in right direction or not. As after performing these steps gpio_36 is not toggled between high and low.

Thanks

Sid

Hello Sid,

I confirm that your approach is correct. However, it would be fine to explain us, which hardware and software you use with OMAP4460?

Best regards,

Yanko

Hi Yanko,

I am using a customized board with Jorjin module. I am able to toggle gpio_36 at u-boot level very well.

Thanks 

Sid