[U-Boot] [PATCH] clk: sifive: fu540-prci: align primary DT match string to the DT bindings

[Atish Patra]

On 5/29/19 10:48 PM, Bin Meng wrote:
> On Thu, May 30, 2019 at 1:06 PM Atish Patra <atish.patra at wdc.com> wrote:
>>
>> On 5/29/19 6:19 PM, Bin Meng wrote:
>>> On Sun, May 26, 2019 at 5:13 PM Paul Walmsley <paul.walmsley at sifive.com> wrote:
>>>>
>>>> The U-Boot PRCI driver for the SiFive FU540 uses an out-of-date DT
>>>> binding string, since the U-boot PRCI driver was upstreamed before the
>>>
>>> nits: U-boot -> U-Boot
>>>
>>>> mainline Linux kernel PRCI driver was finished.  This means that the
>>>> U-Boot PRCI driver won't probe when used with a DT file that is
>>>> aligned to the DT bindings and the driver in the Linux kernel:
>>>>
>>>>      https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/Documentation/devicetree/bindings/clock/sifive/fu540-prci.txt#n7
>>>>
>>>>      https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/drivers/clk/sifive/fu540-prci.c#n610
>>>>
>>>> Fix by aligning the U-Boot DT match string to the string that's used
>>>> in the upstream DT bindings and the Linux kernel driver.
>>>>
>>>>
>>>> Signed-off-by: Paul Walmsley <paul.walmsley at sifive.com>
>>>> Signed-off-by: Paul Walmsley <paul at pwsan.com>
>>>> Cc: Anup Patel <Anup.Patel at wdc.com>
>>>> Cc: Atish Patra <atish.patra at wdc.com>
>>>> Cc: Alexander Graf <agraf at suse.de>
>>>> ---
>>>>    drivers/clk/sifive/fu540-prci.c | 2 +-
>>>>    1 file changed, 1 insertion(+), 1 deletion(-)
>>>>
>>>> diff --git a/drivers/clk/sifive/fu540-prci.c b/drivers/clk/sifive/fu540-prci.c
>>>> index 2d47ebc6b1..d79d1a5351 100644
>>>> --- a/drivers/clk/sifive/fu540-prci.c
>>>> +++ b/drivers/clk/sifive/fu540-prci.c
>>>> @@ -589,7 +589,7 @@ static struct clk_ops sifive_fu540_prci_ops = {
>>>>    };
>>>>
>>>>    static const struct udevice_id sifive_fu540_prci_ids[] = {
>>>> -       { .compatible = "sifive,fu540-c000-prci0" },
>>>> +       { .compatible = "sifive,fu540-c000-prci" },
>>>
>>> Can we keep the previous compatible string for compatibility reason?
>>> U-Boot is now reusing the DT that FSBL passes. Changing the name here
>>> means we need re-flash an updated FSBL?
>>
>> Unfortunately yes. However, you can also use OpenSBI/BBL to use the
>> updated DT instead of DT from FSBL.
>>
>> OpenSBI method: Just use the additional argument during OpenSBI compilation.
>>
>> FW_PAYLOAD_FDT_PATH=<linux kernel
>> source>/arch/riscv/boot/dts/sifive/hifive-unleashed-a00.dtb
> 
> OK, please update the doc/README.sifive-fu540, to mention an updated
> FDT needs to be provided to OpenSBI, if we remove the old compatible
> string in the U-Boot PRCI driver.
> 

Sure. I think we need to update it anyways once the clock driver is 
fixed as per new DT. I have not looked into details but I was not able 
to boot U-Boot only with this patch after using the new DT from kernel.

This is expected as compatible string is not the only change as 
described in Linux mailing list[1].

[1] http://lists.infradead.org/pipermail/linux-riscv/2019-April/004259.html
>>
>> BBL: Paul has a working branch. Details are here
>>
>> http://lists.infradead.org/pipermail/linux-riscv/2019-May/004685.html
>>
> 
> Regards,
> Bin
> 


-- 
Regards,
Atish