[U-Boot] [PATCH V2 2/2] ARM: tegra: Add p2371-0000 board

[Stephen Warren <swarren@wwwdotorg.org>]

On 08/19/2015 07:56 AM, Thierry Reding wrote:
> On Wed, Jul 29, 2015 at 02:16:33PM -0600, Stephen Warren wrote:
>> From: Stephen Warren <swarren@nvidia.com>
>>
>> Signed-off-by: Stephen Warren <swarren@nvidia.com>
>> ---
>> v2: Use named constants for PMIC I2C and register addresses.
>> ---
>>   arch/arm/dts/Makefile                              |   1 +
>>   arch/arm/dts/tegra210-p2371-0000.dts               |  59 +++++
>>   arch/arm/mach-tegra/tegra210/Kconfig               |   6 +
>>   board/nvidia/p2371-0000/Kconfig                    |  12 +
>>   board/nvidia/p2371-0000/MAINTAINERS                |   6 +
>>   board/nvidia/p2371-0000/Makefile                   |   8 +
>>   board/nvidia/p2371-0000/p2371-0000.c               |  51 ++++
>>   board/nvidia/p2371-0000/pinmux-config-p2371-0000.h | 260 +++++++++++++++++++++
>>   configs/p2371-0000_defconfig                       |  16 ++
...
>
> Sorry for being late on this. I just rebased my tree on origin/master
> and got rid of my preliminary P2371 patches in favour of this only to
> notice that it doesn't work the way it used to. For example I used to
> use:
>
> 	# ums 0 mmc 1
>
> to upload kernel, DTB and such to the external SD card. Unfortunately
> that no longer works with this version of the patches. I tried to see
> what the differences are but couldn't spot anything. I see that dmesg
> shows a bunch of USB device reset messages, and failures to read the
> superblock on /dev/sdc, which is what the mass storage shows up as. I
> also tried porting a couple of changes from my earlier tree over to
> master, but to no avail.
>
> Any ideas what could be the reason here? Does the external SD card work
> for anybody else?

It certainly did when I tested it. I haven't tested it on this 
particular board since the patch was actually applied though.

A few questions:

- Do regular filesystem commands such as part list, ls, load work on the 
SD card?

- Does ums work on the eMMC but not SD, or fail on both?

Perhaps related: I have just noticed that one of my SD cards works just 
fine in p2371-2180 but the other card doesn't. I swear they both used to 
work. Unfortunately I can't test those cards on p2371-0000 since it has 
a uSD slot instead of full-size. I've also noticed some stability issues 
with "ums" even on the eMMC; basic stuff like the device enumeration and 
various sized dd operations work fine, but mounting filesystems doesn't 
always work. I'll see if I can work out what's up. I wonder if the 
recent T210 clock driver patches had anything to do with this; IIRC they 
didn't exist when I first did all these board ports.

> I also noticed two other things:
>
>> diff --git a/configs/p2371-0000_defconfig b/configs/p2371-0000_defconfig
> [...]
>> +CONFIG_USE_PRIVATE_LIBGCC=y
>
> Why do we need this?

I copied the configuration from the p2571 patches that Tom sent, to keep 
all the T210 boards consistent. Perhaps Tom can shed some light? FWIW, I 
tested removing that line for p2371-2180 and the build and boot to 
U-Boot prompt still seemed to work. This option might be a hold-over 
from previous chips where SPL existed and needed to be built with 
different CPU options. Perhaps we can remove this.

>> diff --git a/include/configs/p2371-0000.h b/include/configs/p2371-0000.h
> [...]
>> +#define COUNTER_FREQUENCY	38400000
>
> As far as I know the system counter is actually clocked by clk_m, which
> on most (all?) Tegra210 platforms will be configured to run at half the
> oscillator frequency (19.2 MHz). This is corroborated by the fact that
> running:
>
> 	# sleep 5
>
> actually takes 10 seconds rather than the expected 5. Changing the above
> to 19200000 fixes that.

That's odd. I just tested this on p2371-2180 which should have the same 
basic clock/crystal setup, and "sleep 10" takes 10 seconds. What SW are 
you using as the primary bootloader? I'm using nvtboot from our internal 
L4T main branch. Once that's released, I would expect people to use that 
same thing (and NVIDIAns can use it already:-)