[U-Boot] [PATCH v3] dm: core: Enable optional use of fdt_translate_address()

[Stefan Roese]

Hi Bin,

On 03.12.2015 14:34, Bin Meng wrote:
> Hi Stefan, Simon,
>
> On Mon, Oct 19, 2015 at 7:16 AM, Simon Glass <sjg at chromium.org> wrote:
>> On 29 September 2015 at 23:00, Stefan Roese <sr at denx.de> wrote:
>>> The current "simple" address translation simple_bus_translate() is not
>>> working on some platforms (e.g. MVEBU). As here more complex "ranges"
>>> properties are used in many nodes (multiple tuples etc). This patch
>>> enables the optional use of the common fdt_translate_address() function
>>> which handles this translation correctly.
>>>
>>> Signed-off-by: Stefan Roese <sr at denx.de>
>>> Cc: Simon Glass <sjg at chromium.org>
>>> Cc: Bin Meng <bmeng.cn at gmail.com>
>>> Cc: Marek Vasut <marex at denx.de>
>>> Cc: Masahiro Yamada <yamada.masahiro at socionext.com>
>>> Cc: Stephen Warren <swarren at nvidia.com>
>>> Cc: Lukasz Majewski <l.majewski at samsung.com>
>>> ---
>>> v3:
>>> - Rebased on current U-Boot version
>>> - Added Stephen and Lukasz to Cc
>>>
>>> v2:
>>> - Rework code a bit as suggested by Simon. Also added some comments
>>>    to make the use of the code paths more clear.
>>>
>>>   drivers/core/Kconfig  | 30 ++++++++++++++++++++++++++++++
>>>   drivers/core/device.c | 20 ++++++++++++++++++++
>>>   2 files changed, 50 insertions(+)
>>
>> Applied to u-boot-dm, thanks!
>
> When testing Simon's patch [1], I found PCI UART on Intel Crown Bay no
> longer works. git bisect leads to this commit. Somehow I missed this
> patch before although I see the commit message get me cc'ed but the
> email did not bring to my attention.
>
> I see this patch introduced OF_TRANSLATE and by default set it to y.
> This makes the code logic in dev_get_addr() go through
> fdt_translate_address(), which breaks the things.

I'm a bit surprised that using the common fdt_translate_address()
function instead of the DM internal simple_bus_translate() causes
problems on your platform. Are you sure that the ranges are
described correctly in your dts? Is the dts a copy from the Linux
original one? Ah, probably not, since we're talking about x86
which has no DT support in Linux, right?

> Should we set
> OF_TRANSLATE to n by default? If set to y, this requires dts to have
> complete ranges property everywhere.

My understanding here is that x86 is a special case. As it doesn't
use the full-blown dts sources from Linux. But most likely some
"simple" ones, written exactly for U-Boot / DM.

I would still prefer to have this OF_TRANSLATE set to y as default.
As its needed for at least some platforms. But if we decide to
set it to n, I can live with it as well.

Thanks,
Stefan