[U-Boot] [PATCH RFC] sandbox: Add 64-bit sandbox

[Simon Glass]

Hi Mario,

On 15 January 2018 at 20:28, Simon Glass <sjg at chromium.org> wrote:
> Hi Mario,
>
> On 14 January 2018 at 23:23, Mario Six <mario.six at gdsys.cc> wrote:
>> Hi Simon,
>>
>> On Fri, Dec 29, 2017 at 4:13 AM, Simon Glass <sjg at chromium.org> wrote:
>>> Hi Mario,
>>>
>>> On 20 December 2017 at 07:31, Mario Six <mario.six at gdsys.cc> wrote:
>>>> From: Mario Six <six at gdsys.cc>
>>>>
>>>> To debug device tree issues involving 32- and 64-bit platforms, it is useful to
>>>> have a generic 64-bit platform available.
>>>>
>>>> Add a version of the sandbox that uses 64-bit integers for its physical
>>>> addresses as well as a modified device tree.
>>>>
>>>> Signed-off-by: Mario Six <mario.six at gdsys.cc>
>>>>
>>>> ---
>>>>  arch/sandbox/Kconfig             |   6 +
>>>>  arch/sandbox/cpu/cpu.c           |   2 +-
>>>>  arch/sandbox/dts/Makefile        |   4 +
>>>>  arch/sandbox/dts/sandbox64.dts   | 317 +++++++++++++++++++++++++++++++++++++++
>>>>  arch/sandbox/include/asm/io.h    |   6 +
>>>>  arch/sandbox/include/asm/types.h |  14 +-
>>>>  cmd/demo.c                       |   6 +-
>>>>  configs/sandbox64_defconfig      | 200 ++++++++++++++++++++++++
>>>>  drivers/demo/demo-simple.c       |   2 +-
>>>>  9 files changed, 550 insertions(+), 7 deletions(-)
>>>>  create mode 100644 arch/sandbox/dts/sandbox64.dts
>>>>  create mode 100644 configs/sandbox64_defconfig
>>>
>>> Reviewed-by: Simon Glass <sjg at chromium.org>
>>>
>>> Can you please update the sandbox README?
>>>
>>
>> Sure, I'll extend the README.
>>
>>> Also, how does this play with CONFIG_SANDBOX_64BIT and CONFIG_PHYS_64BIT ?
>>>
>>
>> Yeah, the names of the config options are all a bit confusing (hence why I
>> added the RFC to see if someone may have a better idea). Setting the
>> CONFIG_PHYS_64BIT is not strictly necessary for the 64-bit sandbox, but some
>> architectures use the option to decide whether they run on a 32- or 64-bit
>> system, so I thought it was consistent to also set it, just in case. The
>> CONFIG_SANDBOX_64BIT option causes a 64-bit sandbox *binary* to be built. This
>> binary still uses 32-bit-wide types in the device tree (phys_addr_t and
>> phys_size_t, mostly, so the width of the physical addresses are still 32-bit),
>> so that's not what we want in this case. I decided to override the type
>> definitions in arch/sandbox/include/asm/types.h based on CONFIG_SANDBOX64
>> directly, since I didn't want to introduce yet another option that has the
>> words sandbox and 64 in its name. But it's pretty confusing still, I admit.
>>
>> Maybe we could rename CONFIG_SANDBOX_64BIT to CONFIG_HOST_64BIT, and use
>> CONFIG_PHYS_64BIT to control the width of the physical addresses in types.h
>> (which is what it is used for in arch/arm/include/asm/types.h now that I'm
>> taking a closer look); that would at least make the names congruent with their
>> actual semantics. We would then have the options CONFIG_HOST_64BIT,
>> CONFIG_PHYS_64BIT, and CONFIG_SANDBOX64 as the "board option".
>>
>> Maybe that's a cleaner solution?
>
> Yes I think that is a good idea.

Do you have a new version in the works?

Regards,
Simon