CCS/AM3358: IO pads in dts file

RAJU KUMARKHANIYA

Expert 1110 points

Part Number: AM3358

Tool/software: Code Composer Studio

hello everyone,

right now i'm working in am335x based application

when i start modification in dts file i saw pin map for user led

AM33XX_IOPAD(0x810, PIN_OUTPUT_PULLDOWN | MUX_MODE7)   /* gpmc_ad4.gpio1_4 */
AM33XX_IOPAD(0x814, PIN_OUTPUT_PULLDOWN | MUX_MODE7)   /* gpmc_ad5.gpio1_5 */
AM33XX_IOPAD(0x818, PIN_OUTPUT_PULLDOWN | MUX_MODE7)   /* gpmc_ad6.gpio1_6 */
AM33XX_IOPAD(0x81c, PIN_OUTPUT_PULLDOWN | MUX_MODE7)   /* gpmc_ad7.gpio1_7 */

but i'm unable to find what exact meaning of ->0x810, 0x814,0x818,0x81c,

what does it mean that....?

over 5 years ago

0 Pavel Botev over 5 years ago

TI__Guru**** 170625 points

Hi Raju,

0x810 is the offset of the conf_gpmc_ad4 register, which is used to configure this pin.

In AM335x TRM, conf_gpmc_ad4 is at address 0x44E10810, which is composed of Control Module base address (0x44E10000) and conf_gpmc_ad4 register offset (0x810). For more info please refer to below TRM sections:

2.1 ARM Cortex-A8 Memory Map - Table 2-2. L4_WKUP Peripheral Memory Map

9.3.1 CONTROL_MODULE Registers

Regards,
Pavel

0 RAJU KUMARKHANIYA over 5 years ago in reply to Pavel Botev

Expert 1110 points

Thank You so much Mr. Pavel

got it your answer.

i have one more question if i want to add new pin as an an only GPIO which is not defined or used by other module like uart, i2c or ethernet.

then what should i have to do....?

like modify in dts file, etc. or which other file i have to modify and how to add this new gpio pin confing step in dts file.

thanks and regard Raju

0 Pavel Botev over 5 years ago in reply to RAJU KUMARKHANIYA

TI__Guru**** 170625 points

Raju,

You can make this GPIO stand alone pinmux in u-boot at below file:

u-boot/board/ti/am335x/mux.c

See for example how gpio0_7 and gpio0_18 pins are configured and reuse this approach:

static struct module_pin_mux gpio0_7_pin_mux[] = {
   {OFFSET(ecap0_in_pwm0_out), (MODE(7) | PULLUDEN)},   /* GPIO0_7 */
   {-1},
};

static struct module_pin_mux gpio0_18_pin_mux[] = {
   {OFFSET(usb0_drvvbus), (MODE(7) | PULLUDEN)},   /* GPIO0_18 */
   {-1},
};

void enable_board_pin_mux(void)
{

else if (board_is_evm_sk()) {
/* Starter Kit EVM */
configure_module_pin_mux(gpio0_7_pin_mux);

}

else if (board_is_icev2()) {
configure_module_pin_mux(gpio0_18_pin_mux);

}

Then you need to build new SPL/MLO and u-boot images, check below user guide:

Regards,
Pavel

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CCS/AM3358: IO pads in dts file