[U-Boot] [PATCH 07/10] x86: Add I/O APIC register access inline routines

[Simon Glass]

Hi Bin,

On 17 June 2015 at 01:35, Bin Meng <bmeng.cn at gmail.com> wrote:
> Hi Simon,
>
> On Tue, Jun 16, 2015 at 10:46 AM, Simon Glass <sjg at chromium.org> wrote:
>> Hi Bin,
>>
>> On 15 June 2015 at 01:59, Bin Meng <bmeng.cn at gmail.com> wrote:
>>> I/O APIC registers are addressed indirectly. Add io_apic_read() and
>>> io_apic_write() inline routines. Two macros for I/O APIC ID and
>>> version register offset are also added.
>>>
>>> Signed-off-by: Bin Meng <bmeng.cn at gmail.com>
>>> ---
>>>
>>>  arch/x86/include/asm/ioapic.h | 34 ++++++++++++++++++++++++++++++++++
>>>  1 file changed, 34 insertions(+)
>>>
>>> diff --git a/arch/x86/include/asm/ioapic.h b/arch/x86/include/asm/ioapic.h
>>> index f5d69db..697eabb 100644
>>> --- a/arch/x86/include/asm/ioapic.h
>>> +++ b/arch/x86/include/asm/ioapic.h
>>> @@ -9,10 +9,44 @@
>>>  #ifndef __ASM_IOAPIC_H
>>>  #define __ASM_IOAPIC_H
>>>
>>> +#include <asm/io.h>
>>> +
>>>  #define IO_APIC_ADDR           0xfec00000
>>>
>>>  /* Direct addressed register */
>>>  #define IO_APIC_INDEX          (IO_APIC_ADDR + 0x00)
>>>  #define IO_APIC_DATA           (IO_APIC_ADDR + 0x10)
>>>
>>> +/* Indirect addressed register offset */
>>> +#define IO_APIC_ID             0x00
>>> +#define IO_APIC_VER            0x01
>>> +
>>> +/**
>>> + * io_apic_read() - Read I/O APIC register
>>> + *
>>> + * This routine reads I/O APIC indirect addressed register.
>>> + *
>>> + * @reg:       address of indirect addressed register
>>> + * @return:    register value to read
>>> + */
>>> +static inline u32 io_apic_read(u32 reg)
>>> +{
>>> +       writel(reg, IO_APIC_INDEX);
>>> +       return readl(IO_APIC_DATA);
>>> +}
>>
>> Is there any reason these need to be inline?
>>
>
> No, but I was referring to asm/lapic.h inside which the lapic register
> access routines are inline as well. Do you want to remove inline for
> lapic and ioapic?
>
> [snip]

I'm really just wondering why they are inline. I can't see any
advantage myself. If you agree, then yes let's remove inline for both.

If there is a reason for inline, then let's take this patch as is.

Regards,
Simon