[U-Boot] [PATCH 04/11] net: macb: Fix clk API usage for RISC-V systems

[Alexander Graf]

> Am 18.01.2019 um 07:05 schrieb Anup Patel <Anup.Patel at wdc.com>:
> 
> 
> 
>> -----Original Message-----
>> From: Alexander Graf [mailto:agraf at suse.de]
>> Sent: Thursday, January 17, 2019 11:37 PM
>> To: Anup Patel <Anup.Patel at wdc.com>; Rick Chen <rick at andestech.com>;
>> Bin Meng <bmeng.cn at gmail.com>; Joe Hershberger
>> <joe.hershberger at ni.com>; Lukas Auer <lukas.auer at aisec.fraunhofer.de>;
>> Masahiro Yamada <yamada.masahiro at socionext.com>; Simon Glass
>> <sjg at chromium.org>
>> Cc: Palmer Dabbelt <palmer at sifive.com>; Paul Walmsley
>> <paul.walmsley at sifive.com>; Atish Patra <Atish.Patra at wdc.com>;
>> Christoph Hellwig <hch at infradead.org>; U-Boot Mailing List <u-
>> boot at lists.denx.de>
>> Subject: Re: [PATCH 04/11] net: macb: Fix clk API usage for RISC-V systems
>> 
>>> On 01/17/2019 11:38 AM, Anup Patel wrote:
>>> This patch does following fixes in MACB ethernet driver for using it
>>> on RISC-V systems (particularly QEMU sifive_u
>>> machine):
>>> 1. asm/arch/clk.h is not available on RISC-V port so include
>>>    it only for non-RISC-V systems.
>>> 2. Don't fail in macb_enable_clk() if clk_enable() returns
>>>    -ENOSYS because we get -ENOSYS for fixed-rate clocks.
>>> 
>>> Signed-off-by: Anup Patel <anup.patel at wdc.com>
>>> Reviewed-by: Bin Meng <bmeng.cn at gmail.com>
>>> ---
>>>  drivers/net/macb.c | 4 +++-
>>>  1 file changed, 3 insertions(+), 1 deletion(-)
>>> 
>>> diff --git a/drivers/net/macb.c b/drivers/net/macb.c index
>>> 94c89c762b..9a06b523cc 100644
>>> --- a/drivers/net/macb.c
>>> +++ b/drivers/net/macb.c
>>> @@ -38,7 +38,9 @@
>>>  #include <linux/mii.h>
>>>  #include <asm/io.h>
>>>  #include <asm/dma-mapping.h>
>>> +#ifndef CONFIG_RISCV
>>>  #include <asm/arch/clk.h>
>>> +#endif
>>>  #include <linux/errno.h>
>>> 
>>>  #include "macb.h"
>>> @@ -1066,7 +1068,7 @@ static int macb_enable_clk(struct udevice *dev)
>>>       */
>>>  #ifndef CONFIG_MACB_ZYNQ
>>>      ret = clk_enable(&clk);
>> 
>> If clk.h is not available, who exports clk_enable() then; and why is the
>> included needed in the first place?
> 
> For some of the ARM boards, clk instances are provided
> directly by arch/arm/mach-xyz sources. For such boards,
> asm/arch/clk.h is required. I think these boards should
> move to DT based clk drivers.

Can you at least make this a positive #ifdef then rather than ifndef? We want to isolate the odd case, not the normal one.

Maybe you can even find a config option that isolates it further?


Alex

> 
> In all other cases, we use generic <clk.h> which provides
> clk instances using DT based clk drivers.
> 
> Regards,
> Anup