On Wed 06 Jun 13:32 PDT 2018, Luis R. Rodriguez wrote:

On Fri, Jun 01, 2018 at 09:23:46PM +0200, Luis R. Rodriguez wrote:

quoted

On Tue, May 08, 2018 at 03:38:05PM +0000, Luis R. Rodriguez wrote:

quoted

On Fri, May 04, 2018 at 12:44:37PM -0700, Martijn Coenen wrote:

quoted

I think the Qualcomm folks owning this (Andy, David, Bjorn, already
cc'd here) are better suited to answer that question.

Andy, David, Bjorn?

Andy, David, Bjorn?

A month now with no answer...

The patch at the top of this thread doesn't interest me and you didn't
bother sending your question To me.

As a matter of fact I'm confused to what the actual question is.

Perhaps someone who has this hardware can find out empirically for us, as
follows (mm folks is this right?):

page = virt_to_page(address);
if (!page)
   fail closed...
if (page_zone(page) == ZONE_DMA || page_zone(page) == ZONE_DMA32)
	this is a DMA buffer
else
	not DMA!

Where do you want to put this?

Note that when request_firmware_into_buf() was being reviewed Mimi had asked back
in 2016 [0] that if a DMA buffer was going to be used READING_FIRMWARE_DMA should be
used otherwise READING_FIRMWARE_PREALLOC_BUFFER was fine.

If it is a DMA buffer *now*, why / how did this change?

From what I can see [0] says is to use READING_FIRMWARE_PREALLOC_BUFFER

regardless of where the memory comes from.

Regards,
Bjorn

[0] https://patchwork.kernel.org/patch/9074611/

  Luis

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