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From:   "Dai WeiBin \(David Dai\)" <david.dai@montage-tech.com>
To:     <linux-cxl@vger.kernel.org>
Subject: CXL_ECN_MailboxReadyTime
Date:   Tue, 22 Jun 2021 09:41:12 +0800
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Hi,

When I think of CXL mailbox interface ready and timeout, an issue is =
troubling me:
>From CXL_ECN_MailboxReadyTime_v5.pdf, Mailbox Ready Time could be at =
most 3 minutes, Host BIOS maybe not be able to endure such big timeout =
duration, so CXL device enumeration maybe fail during BIOS stage. CXL =
device maybe have huge memory which needs a lot of time for training, =
thus device boot-up will take a long period, for this case, a big delay =
maybe exist before mailbox ready. I think if mailbox function doesn't =
ready, BIOS should not refuse CXL device if other functions work well.

Thanks,
David