* dma-coherent property for PCIe Root
@ 2020-09-14 5:23 Valmiki
2020-10-01 5:16 ` Jon Masters
0 siblings, 1 reply; 2+ messages in thread
From: Valmiki @ 2020-09-14 5:23 UTC (permalink / raw)
To: linux-pci, linux-kernel; +Cc: lorenzo.pieralisi, bhelgaas, robh
Hi All,
How does "dma-coherent" property will work for PCIe as RC on an
ARM SOC ?
Because the end point device drivers are the one which will request dma
buffers and Root port driver doesn't involve in data path of end point
except for handling interrupts.
How does EP DMA buffers will be hardware coherent if RC driver exposes
dma-coherent property ?
Regards,
Valmiki
^ permalink raw reply [flat|nested] 2+ messages in thread
* Re: dma-coherent property for PCIe Root
2020-09-14 5:23 dma-coherent property for PCIe Root Valmiki
@ 2020-10-01 5:16 ` Jon Masters
0 siblings, 0 replies; 2+ messages in thread
From: Jon Masters @ 2020-10-01 5:16 UTC (permalink / raw)
To: Valmiki, linux-pci, linux-kernel; +Cc: lorenzo.pieralisi, bhelgaas, robh
On 9/14/20 1:23 AM, Valmiki wrote:
> Hi All,
>
> How does "dma-coherent" property will work for PCIe as RC on an
> ARM SOC ?
> Because the end point device drivers are the one which will request dma
> buffers and Root port driver doesn't involve in data path of end point
> except for handling interrupts.
>
> How does EP DMA buffers will be hardware coherent if RC driver exposes
> dma-coherent property ?
This simply means that the RC supports maintaining coherency, it doesn't
mean that the RC driver does anything. It's a property of the hardware.
Jon.
--
Computer Architect
^ permalink raw reply [flat|nested] 2+ messages in thread
end of thread, other threads:[~2020-10-01 5:16 UTC | newest]
Thread overview: 2+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2020-09-14 5:23 dma-coherent property for PCIe Root Valmiki
2020-10-01 5:16 ` Jon Masters
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).