[U-Boot] [PATCH v7 00/15] SiFive FU540 Support

[Kevin Hilman]

Atish Patra <atish.patra at wdc.com> writes:

> On 4/18/19 4:16 PM, Kevin Hilman wrote:
>> Atish Patra <atish.patra at wdc.com> writes:
>> 
>>> On 4/18/19 12:15 PM, Kevin Hilman wrote:
>>>> Palmer, Anup,
>>>>
>>>> On Tue, Mar 12, 2019 at 1:55 AM Palmer Dabbelt <palmer at sifive.com> wrote:
>>>>>
>>>>> On Mon, 11 Mar 2019 07:33:25 PDT (-0700), bmeng.cn at gmail.com wrote:
>>>>>> On Thu, Feb 14, 2019 at 7:58 AM Kevin Hilman <khilman at baylibre.com> wrote:
>>>>>>>
>>>>>>> Kevin Hilman <khilman at baylibre.com> writes:
>>>>>>>
>>>>>>>> Hi Anup,
>>>>>>>>
>>>>>>>> Anup Patel <Anup.Patel at wdc.com> writes:
>>>>>>>>
>>>>>>>>> This patchset adds SiFive Freedom Unleashed (FU540) support
>>>>>>>>> to RISC-V U-Boot.
>>>>>>>>>
>>>>>>>>> The patches are based upon latest U-Boot source tree
>>>>>>>>> (git://git.denx.de/u-boot.git) at commit id
>>>>>>>>> dbe70c7d4e3d5c705a98d82952e05a591efd0683
>>>>>>>>>
>>>>>>>>> All drivers namely: SiFive PRCI, SiFive Serial, and Cadance
>>>>>>>>> MACB Ethernet work fine on actual SiFive Unleashed board and
>>>>>>>>> QEMU sifive_u machine.
>>>>>>>>
>>>>>>>> I tested u-boot networking (DHCP, TFTP) on my desk with a gigE switch
>>>>>>>> and it worked fine.  Then, I moved it to a lab with a 100Mb switch,
>>>>>>>> and DHCP doesn't work anymore.
>>>>>>>
>>>>>>> And to be clear, neither does TFTP if setting static
>>>>>>> ipaddr/netmask/gatewayip etc.
>>>>>>
>>>>>> Sound to me a bug of the GEM driver on SiFive FU540 board.
>>>>>
>>>>> It looks to me like u-boot is missing a driver for the GEM clockmux in the
>>>>> FU540.  This is necessary to switch between the clock for 1G operation and 100M
>>>>> operation.  Without this you'll just get whatever clock was set up by the
>>>>> previous boot stage (or even worse, reset).
>>>>
>>>> Anyone know if this is fixed in u-boot yet?  I've yet to try the
>>>> latest mainline u-boot, but will if if it's expected to work.
>>>>
>>>
>>> I have not seen a GEM driver for FU540 board. So I guess it is not fixed
>>> it. Is it a blocker for setting up kernelCI for RISC-V ?
>> 
>> Not really, that's only one of the remaining issue. For now, I have
>> connected it to a gigE switch, so u-boot networking is working.
>> 
>> But, the bigger blocker for kernelCI right now is not having
>> out-of-the-box mainline support.  Mainline is still missing a serial
>> driver, and a handful of Kconfig options in the default defconfig to
>> make things boot[1].
>> 
>> If I use the 'v5.1-rc4_unleashed' from your github, along with my
>> kconfig fragment[1], things are working well.
>> 
>> But in order to automate this for kernelCI, we need all of that
>> upstream.
>> 
> Yeah. I agree. We need upstream drivers sooner than later.
> I believe SiFive Team (Paul & co) are working on this.
>
> He recently sent updated version of driver patches to the linux-riscv 
> mailing list.

Yes, I'm trying to test all of those (hence our other discussion on the
DT thread)

>> [1] This is the config fragment I'm adding to the default defconfig in
>> mainline.  I'm not exactly sure which ones are absolutely need for basic
>> boot.
>> 
>> CONFIG_SERIAL_SIFIVE=y
>> CONFIG_SERIAL_SIFIVE_CONSOLE=y
>> CONFIG_SIFIVE_PLIC=y
>> CONFIG_SPI=y
>> CONFIG_SPI_SIFIVE=y
>> CONFIG_GPIOLIB=y
>> CONFIG_GPIO_SIFIVE=y
>> CONFIG_PWM_SIFIVE=y
>> CONFIG_CLK_U54_PRCI=y
>> CONFIG_CLK_GEMGXL_MGMT=y
>> 
>
> My working config has enabled all of the above except CONFIG_PWM_SIFIVE.
> I have not played around the config that much to find out absolute 
> minimum config. So this may not be the answer you are looking for :).

At least for kernelCI, we'll need to figure that out and get it upstream
if we want to boot test these.

Kevin