On 21-02-04 21:53:29, John Groves (jgroves) wrote:

   Micron Confidential



   From: Dan Williams [off-list ref]
   Date: Monday, February 1, 2021 at 1:28 PM
   To: Ben Widawsky [off-list ref]
   Cc: Konrad Rzeszutek Wilk [off-list ref],
   linux-cxl@vger.kernel.org [off-list ref], Linux ACPI
   [off-list ref], Linux Kernel Mailing List
   [off-list ref], linux-nvdimm
   [off-list ref], Linux PCI [off-list ref],
   Bjorn Helgaas [off-list ref], Chris Browy
   [off-list ref], Christoph Hellwig [off-list ref], Ira
   Weiny [off-list ref], Jon Masters [off-list ref], Jonathan
   Cameron [off-list ref], Rafael Wysocki
   [off-list ref], Randy Dunlap [off-list ref],
   Vishal Verma [off-list ref], daniel.lll@alibaba-inc.com
   [off-list ref], John Groves (jgroves)
   [off-list ref], Kelley, Sean V [off-list ref]
   Subject: [EXT] Re: [PATCH 04/14] cxl/mem: Implement polled mode mailbox

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   On Mon, Feb 1, 2021 at 11:13 AM Ben Widawsky [off-list ref]
   wrote:
   >
   > On 21-02-01 12:54:00, Konrad Rzeszutek Wilk wrote:
   > > > +#define
   cxl_doorbell_busy(cxlm)
   \
   > > > +   (cxl_read_mbox_reg32(cxlm, CXLDEV_MB_CTRL_OFFSET)
   &                    \
   > > > +    CXLDEV_MB_CTRL_DOORBELL)
   > > > +
   > > > +#define CXL_MAILBOX_TIMEOUT_US 2000
   > >
   > > You been using the spec for the values. Is that number also from it
   ?
   > >
   >
   > Yes it is. I'll add a comment with the spec reference.



   From section 8.2.8.4 in the CXL 2.0 spec: “The mailbox command timeout
   is 2 seconds.”  So this should be:


   #define CXL_MAILBOX_TIMEOUT_US 2000000


   …right? 2000us is 2ms…

Thanks. This was caught already in earlier review by David Rientjes
[off-list ref]

It's renamed CXL_MAILBOX_TIMEOUT_MS 2000