Re: [PATCH v3 2/3] openrisc: Add pci bus support

From: Guenter Roeck <linux@roeck-us.net>
To: Stafford Horne <shorne@gmail.com>
Cc: LKML <linux-kernel@vger.kernel.org>,
	Bjorn Helgaas <helgaas@kernel.org>, Arnd Bergmann <arnd@arndb.de>,
	Jonas Bonn <jonas@southpole.se>,
	Stefan Kristiansson <stefan.kristiansson@saunalahti.fi>,
	Palmer Dabbelt <palmer@rivosinc.com>,
	Peter Zijlstra <peterz@infradead.org>,
	openrisc@lists.librecores.org
Subject: Re: [PATCH v3 2/3] openrisc: Add pci bus support
Date: Thu, 28 Jul 2022 23:10:37 -0700	[thread overview]
Message-ID: <ceb732ee-0ea1-b471-0b57-3cc3bcb80a2d@roeck-us.net> (raw)
In-Reply-To: <YuN1PWcDukEPdtQy@antec>

On 7/28/22 22:50, Stafford Horne wrote:
> On Thu, Jul 28, 2022 at 08:37:28PM -0700, Guenter Roeck wrote:
>> On Mon, Jul 25, 2022 at 11:07:36AM +0900, Stafford Horne wrote:
>>> This patch adds required definitions to allow for PCI buses on OpenRISC.
>>> This is being tested on the OpenRISC QEMU virt platform which is in
>>> development.
>>>
>>> OpenRISC does not have IO ports so we keep the definition of
>>> IO_SPACE_LIMIT and PIO_RESERVED to be 0.
>>>
>>> Note, since commit 66bcd06099bb ("parport_pc: Also enable driver for PCI
>>> systems") all platforms that support PCI also need to support parallel
>>> port.  We add a generic header to support compiling parallel port
>>> drivers, though they generally will not work as they require IO ports.
>>>
>>> Signed-off-by: Stafford Horne <shorne@gmail.com>
>>
>> This patch results in
>>
>> Building openrisc:allmodconfig ... failed
>> --------------
>> Error log:
>> drivers/video/fbdev/riva/fbdev.c: In function 'rivafb_probe':
>> drivers/video/fbdev/riva/fbdev.c:2062:42: error:
>> 	passing argument 1 of 'iounmap' discards 'volatile' qualifier from pointer target type
>>
>> drivers/video/fbdev/nvidia/nvidia.c: In function 'nvidiafb_probe':
>> drivers/video/fbdev/nvidia/nvidia.c:1414:20: error:
>> 	passing argument 1 of 'iounmap' discards 'volatile' qualifier from pointer target type
>>
>> drivers/scsi/aic7xxx/aic7xxx_osm.c: In function 'ahc_platform_free':
>> drivers/scsi/aic7xxx/aic7xxx_osm.c:1231:41: error:
>> 	passing argument 1 of 'iounmap' discards 'volatile' qualifier from pointer target type
>>
>> ... and so on.
>>
>> Prior to this patch, the code was not enabled because it depends on PCI.
> 
> Hi Guenter,
> 
> Thanks for reporting this.
> 
> It's interesting, I don't get this on the openrisc/for-next branch.
> 

Hmm, weird. I see it all over the place. Complete log is at
https://kerneltests.org/builders/next-openrisc-next/builds/1880/steps/buildcommand/logs/stdio
if you are interested.

> BTW, do you turn off WERROR on the allmodconfig config?  I get many warnings
> such as the below, but I haven't looked into it much yet:
> 

No, I don't. Disabling it would defeat its purpose.

>      fs/exec.c: In function 'shift_arg_pages':
>      fs/exec.c:687:27: error: 'tlb' is used uninitialized [-Werror=uninitialized]
>        687 |         struct mmu_gather tlb;
> 	  |                           ^~~
> 

I don't see that in next-20220728. I tried with gcc-11.2 and 11.3.
Which compiler do you use ?

Thanks,
Guenter

> I will try to see what is going on in linux-next.
> 
> -Stafford
> 