[PATCH 5/6] ARM: convert PCI defines to variables
Rob Herring
robherring2 at gmail.com
Sat Jul 2 08:40:19 EDT 2011
Arnd,
On 07/02/2011 04:21 AM, Arnd Bergmann wrote:
> Hi Rob,
>
> On Wednesday 29 June 2011 18:46:58 Rob Herring wrote:
>> From: Rob Herring <rob.herring at calxeda.com>
>>
>> Convert PCIBIOS_MIN_IO and PCIBIOS_MIN_MEM to variables to allow
>> multi-platform builds. This also removes the requirement for a platform to
>> have a mach/hardware.h.
>
> Good idea.
>
>> @@ -24,6 +23,12 @@ EXPORT_SYMBOL(ioport_unmap);
>> #endif
>>
>> #ifdef CONFIG_PCI
>> +unsigned long pcibios_min_io;
>> +EXPORT_SYMBOL(pcibios_min_io);
>> +
>> +unsigned long pcibios_min_mem;
>> +EXPORT_SYMBOL(pcibios_min_mem);
>> +
>
> How about setting these to sensible defaults that will work on
> most platforms, so that the majority won't have to set them at
> all?
>
> Basically, the defaults should clearly be
>
> unsigned long pcibios_min_io = 0x1000;
> unsigned long pcibios_min_mem = 0x01000000;
>
> This just gets us out of the ISA bus range, so an ISA card behind
> a bridge can use all cards correctly. Most of the ones that
> currently set both to zero can probably just use those defaults
> as well, but some architectures have multiple buses or don't start
> the memory range at zero, so they might need higher values.
For many platforms, the defaults are 0 for both of these, so I went with
that. Do you think those are just wrong?
Rob
>
>> --- a/arch/arm/mach-versatile/include/mach/hardware.h
>> +++ b/arch/arm/mach-versatile/include/mach/hardware.h
>> @@ -30,10 +30,6 @@
>> #define VERSATILE_PCI_VIRT_BASE (void __iomem *)0xe8000000ul
>> #define VERSATILE_PCI_CFG_VIRT_BASE (void __iomem *)0xe9000000ul
>>
>> -/* CIK guesswork */
>> -#define PCIBIOS_MIN_IO 0x44000000
>> -#define PCIBIOS_MIN_MEM 0x50000000
>> -
>> /* macro to get at IO space when running virtually */
>> #define IO_ADDRESS(x) (((x) & 0x0fffffff) + (((x) >> 4) & 0x0f000000) + 0xf0000000)
>>
>
> This PCIBIOS_MIN_IO setting is wrong, and PIO doesn't work on versatile
> because of this. I have an older patch series that I should dig out again
> to fix them and make versatile use the defaults. Don't worry about this
> one.
>
> Arnd
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