[U-Boot] [PATCH V3 6/6] T210: Add support for 64-bit T210-based P2571 board

[Stephen Warren <swarren@wwwdotorg.org>]

On 07/24/2015 04:01 PM, Tom Warren wrote:
> Based on Venice2, incorporates Stephen Warren's
> latest P2571 pinmux table.
>
> With Thierry Reding's 64-bit build fixes, this
> will build and and boot in 64-bit on my P2571
> (when used with a 32-bit AVP loader).

> diff --git a/board/nvidia/p2571/max77620_init.c b/board/nvidia/p2571/max77620_init.c

> +void pmic_enable_cpu_vdd(void)

This function is never called, or even linked into the binary. For 
previous Tegra SoCs, it was called from the SPL before booting the 
CCPLEX. Since there is no SPL for Tegra210, nothing calls this.

> +	debug("%s: Set LDO2 for VDDIO_SDMMC_AP power to 3.3V\n", __func__);
> +	/* 0xF2 for 3.3v, enabled: bit7:6 = 11 = enable, bit5:0 = voltage */
> +	reg = 0xF200 | MAX77620_CNFG1_L2_REG;
> +	tegra_i2c_ll_write_addr(MAX77620_I2C_ADDR, 2);
> +	tegra_i2c_ll_write_data(reg, I2C_SEND_2_BYTES);
> +	udelay(10 * 1000);

This explains why the SD card isn't working for me on p2371-2180; I 
guess the PMIC OTP on that board has this regulator disabled, and since 
this code never runs, it never gets turned on. If I manually turn it on 
using the i2c command, then "mmc dev 1" works.

For p2571, I think we should either delete this file entirely. Or, at 
least strip it down so that it's not touching global PMIC configuration 
but rather just enabling any non-CCPLEX rails that U-Boot might need 
such as SD card and USB, then rename the function and arrange for it to 
be called from somewhere. I'm not sure what a good name and call-site 
would be yet.