Date: Wed, 22 Jan 2020 01:04:27 +0000 (UTC) From: Alexander Motin <mav@FreeBSD.org> To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-stable@freebsd.org, svn-src-stable-12@freebsd.org Subject: svn commit: r356960 - stable/12/share/man/man4 Message-ID: <202001220104.00M14RbB042479@repo.freebsd.org>
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Author: mav Date: Wed Jan 22 01:04:26 2020 New Revision: 356960 URL: https://svnweb.freebsd.org/changeset/base/356960 Log: MFC r351357 (by imp): Document RST support in nvme(4) and ahci(4). Modified: stable/12/share/man/man4/ahci.4 stable/12/share/man/man4/nvme.4 Directory Properties: stable/12/ (props changed) Modified: stable/12/share/man/man4/ahci.4 ============================================================================== --- stable/12/share/man/man4/ahci.4 Wed Jan 22 01:03:24 2020 (r356959) +++ stable/12/share/man/man4/ahci.4 Wed Jan 22 01:04:26 2020 (r356960) @@ -24,7 +24,7 @@ .\" .\" $FreeBSD$ .\" -.Dd November 2, 2018 +.Dd August 21, 2019 .Dt AHCI 4 .Os .Sh NAME @@ -153,6 +153,26 @@ subclass 6 (SATA) and programming interface 1 (AHCI). Also, in cooperation with atamarvell and atajmicron drivers of ata(4), it supports AHCI part of legacy-PATA + AHCI-SATA combined controllers, such as JMicron JMB36x and Marvell 88SE61xx. +.Pp +The +.Nm +driver also supports AHCI devices that act as PCI bridges for +.Xr nvme 4 +using Intel Rapid Storage Technology (RST). +To use the +.Xr nvme 4 +device, either one must set the SATA mode in the BIOS to AHCI (from RST), +or one must accept the performance with RST enabled due to interrupt sharing. +.Fx +will automatically detect AHCI devices with this extension that are in RST +mode. +When that happens, +.Nm +will attach +.Xr nvme 4 +children to the +.Xr ahci 4 +device. .Sh FILES .Bl -tag -width /dev/led/ahcich*.locate .It Pa /dev/led/ahci*.*.act Modified: stable/12/share/man/man4/nvme.4 ============================================================================== --- stable/12/share/man/man4/nvme.4 Wed Jan 22 01:03:24 2020 (r356959) +++ stable/12/share/man/man4/nvme.4 Wed Jan 22 01:04:26 2020 (r356960) @@ -33,7 +33,7 @@ .\" .\" $FreeBSD$ .\" -.Dd December 7, 2018 +.Dd August 21, 2019 .Dt NVME 4 .Os .Sh NAME @@ -192,6 +192,23 @@ with a completion entry that was posted by the control (W) Writing 1 to this sysctl will dump the full contents of the submission and completion queues to the console. .El +.Pp +In addition to the typical pci attachment, the +.Nm +driver supports attaching to a +.Xr ahci 4 +device. +Intel's Rapid Storage Technology (RST) hides the nvme device +behind the AHCI device due to limitations in Windows. +However, this effectively hides it from the +.Fx +kernel. +To work around this limitation, +.Fx +detects that the AHCI device supports RST and when it is enabled. +See +.Xr ahci 4 +for more details. .Sh SEE ALSO .Xr nda 4 , .Xr nvd 4 ,
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