[U-Boot] [PATCH 2/2] Tegra: MMC: Add DT support to MMC driverforall T20 boards

[Tom Warren]

Marc,

On Tue, Feb 5, 2013 at 1:06 PM, Marc Dietrich <marvin24 at gmx.de> wrote:
> On Tuesday 05 February 2013 08:31:03 Tom Warren wrote:
>> Marc,
>>
>> On Tue, Feb 5, 2013 at 2:28 AM, Marc Dietrich <marvin24 at gmx.de> wrote:
>> >>
>> >> [...]
>> >>
>> >> diff --git a/board/compal/paz00/paz00.c b/board/compal/paz00/paz00.c
>> >> index 1447f47..5cee91a 100644
>> >> --- a/board/compal/paz00/paz00.c
>> >> +++ b/board/compal/paz00/paz00.c
>> >> @@ -55,18 +55,18 @@ static void pin_mux_mmc(void)
>> >>
>> >>  /* this is a weak define that we are overriding */
>> >>  int board_mmc_init(bd_t *bd)
>> >>  {
>> >>
>> >> -     debug("board_mmc_init called\n");
>> >> +     debug("%s called\n", __func__);
>> >>
>> >>       /* Enable muxes, etc. for SDMMC controllers */
>> >>       pin_mux_mmc();
>> >>
>> >> -     debug("board_mmc_init: init eMMC\n");
>> >> -     /* init dev 0, eMMC chip, with 8-bit bus */
>> >> -     tegra_mmc_init(0, 8, -1, -1);
>> >> +     debug("%s: init eMMC\n", __func__);
>> >> +     /* init dev 0, eMMC chip */
>> >> +     tegra_mmc_init(0);
>> >
>> > This looks wrong because the sd is on sdmmc0
>> >
>> >> -     debug("board_mmc_init: init SD slot\n");
>> >> -     /* init dev 3, SD slot, with 4-bit bus */
>> >> -     tegra_mmc_init(3, 4, GPIO_PV1, GPIO_PV5);
>> >> +     debug("%s: init SD slot\n", __func__);
>> >> +     /* init dev 3, SD slot */
>> >> +     tegra_mmc_init(3);
>> >
>> > and the emmc on sdmmc3. The DTS is correct.
>> >
>> > Not your fault as it seems to be wrong in the original code already.
>> > I guess it didn't made large difference but may in the future. I wonder
>> > how to test this though.
>> >
>> > Marc
>>
>> OK, so just the comments are wrong in paz00.c - I can fix that if I
>> have to do a V2 patchset, or when I apply the patches to u-boot-tegra.
>
> ah no, this is weird!
>
>         index 3 maps to sdmmc1
>         index 2 maps to sdmmc2
>         index 1 maps to sdmmc3
>         index 0 maps to sdmmc4
>
> so all is fine, nearly ...
>
>> As to testing, just stop at the command prompt and select each device
>> (mmc dev 0, etc.) and run mmcinfo. You should be able to tell from the
>> data displayed whether you are on an SD-card or eMMC chip. You can
>> also eject the SD-card and you should get a warning about card
>> presence due to the CD GPIO.
>
> the sd card is not detected because:
>
> TEGRA20
> Board: Compal Paz00
> DRAM:  512 MiB
> MMC:   tegra_get_setup: dev_index = 0
> tegra_get_setup: count of nodes is 2
> tegra_get_setup: found controller at c8000600, width = 8, periph_id = 15
> tegra_mmc_init: index 0, bus width 8 pwr_gpio -1 cd_gpio -1
> tegra_mmc_init: bus width = 8
> tegra_get_setup: dev_index = 3
> tegra_get_setup: count of nodes is 2
> tegra_get_setup: device index 3 exceeds node count (2)!
>
> If I understand correctly, you are counting the aliases only, not the
> controllers..., so index 3 (the sdcard) is not initialized at all. Arrr,
> debugging stole all of my time, but I guess this needs fixing.
Yep, I am checking the aliases to get a node count (just like the
Tegra SPI, SLINK, and I2C drivers, and the Exynos SPI and S3C I2C
drivers).

I left the Paz00 tegra_mmc_init(3) call the same as originally (w/o
the width and GPIO params, of course). The device numbering is kind of
arbitrary - if there are only 2 MMC devices present, I'd expect dev 0
to be eMMC and dev 1 to be SD (again, like my T20 reference board,
Seaboard).  I don't see that Paz uses mmc anywhere in its config files
for a boot script - does it have to have mmc dev 3 be SD? or would dev
1 work? Note that the tegra20-common-post.h file that all T20 boards
inherit uses dev 0 and dev 1.

Let me look into it - wish I had a Paz00 board here to debug with.
I'll try to simulate this on my Seaboard, maybe with all 4 MMC device
addresses in the alias.

Thanks for the help,

Tom
>
> Marc
>
>
>