On 11/19/2017 09:56 PM, Max Filippov wrote:
On Sat, Nov 18, 2017 at 7:36 PM, ayaka <ayaka@soulik.info> 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. I didn't notice that the IO memory is not cached at the most platform, even the ldd3 have said that. 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. I see, thank you.