Re: [PATCH v1 1/3] ARM64 LPC: indirect ISA PORT IO introduced

Rongrong Zou
2015-12-30T01:34:18Z

在 2015/12/29 22:35, Arnd Bergmann 写道:
> On Tuesday 29 December 2015 22:26:27 Rongrong Zou wrote:
>> 在 2015/12/29 21:47, Arnd Bergmann 写道:
>>> On Tuesday 29 December 2015 21:33:50 Rongrong Zou wrote:
>>>> Indirect ISA port I/O accessing introduced, vendors can hook
>>>> their own in/out function to general inb/outb. Drivers can access
>>>> legacy ISA I/O port by inb/outb as it is done in x86 platform.
>>>>
>>>> Signed-off-by: Rongrong Zou <zourongrong@gmail.com>
>>>
>>> Looks correct to me, but I have a few style comments
>>>
>>>> ---
>>>> arch/arm64/Kconfig.platforms | 5 ++-
>>>> arch/arm64/include/asm/io.h | 78 ++++++++++++++++++++++++++++++++++++++++++++
>>>> arch/arm64/kernel/setup.c | 5 +++
>>>> 3 files changed, 87 insertions(+), 1 deletion(-)
>>>>
>>>> diff --git a/arch/arm64/Kconfig.platforms b/arch/arm64/Kconfig.platforms
>>>> index 4043c35..98ae206 100644
>>>> --- a/arch/arm64/Kconfig.platforms
>>>> +++ b/arch/arm64/Kconfig.platforms
>>>> @@ -127,5 +127,8 @@ config ARCH_ZYNQMP
>>>> bool "Xilinx ZynqMP Family"
>>>> help
>>>> This enables support for Xilinx ZynqMP Family
>>>> -
>>>> +config ARM64_INDIRECT_PIO
>>>> + bool "ARM64 Indirect port I/O"
>>>> + help
>>>> + This enables support for ARM64 indirect port I/O
>>>> endmenu
>>>
>>> The option should probably go into arch/arm64/Kconfig. Possibly you can make
>>> it a silent option that just gets selected whenever a driver is enabled
>>> that might set the callbacks.
>>
>> I try to bind it with HISILICON platform.
>
> It should be possible to build the actual driver on all platforms, at
> least with COMPILE_TEST.

Sorry, I'm a little confused, can you describe it in detail?

>
>>>> diff --git a/arch/arm64/include/asm/io.h b/arch/arm64/include/asm/io.h
>>>> index 44be1e0..0041f3b 100644
>>>> --- a/arch/arm64/include/asm/io.h
>>>> +++ b/arch/arm64/include/asm/io.h
>>>> @@ -193,6 +193,84 @@ extern void __iomem *ioremap_cache(phys_addr_t phys_addr, size_t size);
>>>> */
>>>> #define xlate_dev_kmem_ptr(p) p
>>>>
>>>> +#ifdef CONFIG_ARM64_INDIRECT_PIO
>>>> +#define DEF_PCI_HOOK_pio(x) x
>>>> +#else
>>>> +#define DEF_PCI_HOOK_pio(x) NULL
>>>> +#endif
>>>
>>> Maybe just put the entire definition block inside #ifdef and
>>> fall back to the default inb/outb definitions otherwise.
>>>
>>>> +/*
>>>> + * This value is equal to PCIBIOS_MIN_IO
>>>> + */
>>>> +#define LEGACY_ISA_PORT_MAX 0x1000
>>>
>>> I would just use PCIBIOS_MIN_IO instead of defining another macro.
>>
>> Because PCIBIOS_MIN_IO is defined in asm/pci.h, and asm/io.h
>> is included by asm/pci.h. so do you mean i define PCIBIOS_MIN_IO here,
>> and in asm/pci.h just use include asm/io.h ?
>
> Yes, I guess that would work.
>
> Arnd
>
> .
>