Re: [PATCH 2/3] pci: don't assume pref memio are 64bit -v2

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



Ingo Molnar wrote:
> * Yinghai Lu <yinghai@xxxxxxxxxx> wrote:
> 
>> one system with 4g installed ( there is 1g hole)
>>
>> when 4G installed.
>> BIOS put ACPI etc need the hole
>> [    0.000000] BIOS-provided physical RAM map:
>> [    0.000000]  BIOS-e820: 0000000000000000 - 000000000009bc00 (usable)
>> [    0.000000]  BIOS-e820: 000000000009bc00 - 00000000000a0000 (reserved)
>> [    0.000000]  BIOS-e820: 00000000000e3000 - 0000000000100000 (reserved)
>> [    0.000000]  BIOS-e820: 0000000000100000 - 00000000bffa0000 (usable)
>> [    0.000000]  BIOS-e820: 00000000bffa0000 - 00000000bffae000 (ACPI data)
>> [    0.000000]  BIOS-e820: 00000000bffae000 - 00000000bfff0000 (ACPI NVS)
>> [    0.000000]  BIOS-e820: 00000000bfff0000 - 00000000c0000000 (reserved)
>> [    0.000000]  BIOS-e820: 00000000fee00000 - 00000000fee01000 (reserved)
>> [    0.000000]  BIOS-e820: 00000000ffb00000 - 0000000100000000 (reserved)
>> [    0.000000]  BIOS-e820: 0000000100000000 - 0000000140000000 (usable)
>> so in kernel resource will be reserved for 0xbffa0000 - 0xbfff0000 for ACPI
>> 0x100000 -  0xbffa0000 for RAM...
> 
> btw., sidenote, it would be nice to enhance the e820 table printout 
> with size and hole info as well. I did this manually yesterday in 
> another mail:
> 
> BIOS-provided physical RAM map:
>  BIOS-e820: 0000000000000000 - 000000000009fc00 (usable)       0.639 MB RAM
>  BIOS-e820: 000000000009fc00 - 00000000000a0000 (reserved)     0.001 MB
>                                                 [ hole ]       0.250 MB
>  BIOS-e820: 00000000000e0000 - 0000000000100000 (reserved)     0.125 MB
>  BIOS-e820: 0000000000100000 - 000000003ed94000 (usable)    1004.5   MB RAM
>  BIOS-e820: 000000003ed94000 - 000000003ee4e000 (ACPI NVS)     0.7   MB
>  BIOS-e820: 000000003ee4e000 - 000000003fea2000 (usable)      16.3   MB RAM
>  BIOS-e820: 000000003fea2000 - 000000003fee9000 (ACPI NVS)     0.3   MB
>  BIOS-e820: 000000003fee9000 - 000000003feed000 (usable)       0.15  MB RAM
>  BIOS-e820: 000000003feed000 - 000000003feff000 (ACPI data     0.07  MB
>  BIOS-e820: 000000003feff000 - 000000003ff00000 (usable)       0.004 MB RAM
>                                                 [ hole ]       1.0   MB
>                                                 [ hole ]    3072.0   MB
> 
> it would be extremely useful to have that in the printout, to see 
> the physical address space layout at a glance. Small holes are easy 
> to miss, and e820 entry sizes are hard to judge at a glance.
> 
> To make this fit well, i'd suggest to drop the 'BIOS-e820: ' prefix 
> - it's redundant.

will look at it. and should be another patch for x86.

YH
--
To unsubscribe from this list: send the line "unsubscribe linux-pci" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html

[Index of Archives]     [DMA Engine]     [Linux Coverity]     [Linux USB]     [Video for Linux]     [Linux Audio Users]     [Yosemite News]     [Linux Kernel]     [Linux SCSI]     [Greybus]

  Powered by Linux