Re: why iowrite32_rep() doesn't work, I have to use the iowrite32() with a loop

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

 



On Sat, Nov 18, 2017 at 7:36 PM, ayaka <ayaka@xxxxxxxxxxx> wrote:
> What I want is a relaxed version of the io{read,write}32, as I don't need to
> flush between I am writing the registers table into the registers. I only
> want to flush the cache at the last and isolated register which I will set
> later.

None of these functions do anything with cache. And with
devm_ioremap_resource you will likely get an uncached mapping of your
IO memory, so you don't even need to manage cache.

What you still need to preserve the order of writes is a memory barrier,
and none of io{read,write}32 do it either. You can insert proper barrier
before the write to that last isolated register.

-- 
Thanks.
-- Max

_______________________________________________
Kernelnewbies mailing list
Kernelnewbies@xxxxxxxxxxxxxxxxx
https://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies



[Index of Archives]     [Newbies FAQ]     [Linux Kernel Mentors]     [Linux Kernel Development]     [IETF Annouce]     [Git]     [Networking]     [Security]     [Bugtraq]     [Yosemite]     [MIPS Linux]     [ARM Linux]     [Linux RAID]     [Linux SCSI]     [Linux ACPI]
  Powered by Linux