Re: [PATCH 0/5] Switchtec MRPC DMA mode support

From: Bjorn Helgaas
Date: Thu Dec 13 2018 - 10:20:09 EST


On Mon, Dec 10, 2018 at 05:12:19PM +0800, Wesley Sheng wrote:
> Hi, Everyone,
>
> This patch series adds support for the Switchtec MRPC DMA mode.
>
> Switchtec switches supports 2 MRPC interaction modes: MRPC normal mode and
> MRPC DMA mode, a new feature in the latest firmware versions. MRPC normal
> mode requires the host to read the MRPC command status and output data.
> In MRPC DMA mode the command status and output data are pushed directly to
> host memory and issues an interrupt upon completion. The advantage of MRPC
> DMA mode is avoiding potential high latency response from the Memory Read
> TLP.
>
> Additionally, we've made the following changes:
>
> * Improve the efficiency of filling MRPC Input buffer by enabling write
> combining on MRPC region of BAR
> * Software workaround for delay responded Memory READ TLPs that access
> the BAR
> * And several bug fixes
>
> Regards,
> Wesley
>
> --
>
> Changed since v1:
> - It's a resend of v1
>
> --
>
>
> Boris Glimcher (1):
> switchtec: Set DMA coherent mask in Switchtec driver
>
> Joey Zhang (1):
> switchtec: A temporary variable should be used for the flags of
> switchtec_ioctl_event_ctl
>
> Kelvin Cao (2):
> switchtec: Remove immediate status check after submit a MRPC command
> switchtec: Improve MRPC efficiency by leveraging write combining
>
> Wesley Sheng (1):
> switchtec: MRPC DMA mode implementation
>
> drivers/pci/switch/switchtec.c | 154 ++++++++++++++++++++++++++++++++++++-----
> include/linux/switchtec.h | 16 +++++
> 2 files changed, 153 insertions(+), 17 deletions(-)

I applied all these on pci/switchtec for v4.21, thanks!

If you want to change anything, let me know. I'm happy to replace or
update patches.