svn commit: r349831 - stable/12/sys/dev/ahci

[Alexander Motin]

Author: mav
Date: Mon Jul  8 10:19:49 2019
New Revision: 349831
URL: https://svnweb.freebsd.org/changeset/base/349831

Log:
  MFC r341811 (by delphij):
  Remove questionable initialization for ICH8M, rely on BIOS to properly
  initialize the controller.
  
  According to the datasheet, the old code checks if port 2 (P2E, 0x4) was
  the only enabled port (except port 0, which was ignored by mask 0xfe),
  and issue a write to the PCS register to disable all but port 0, right
  before ahci_ctlr_reset.
  
  Some other operating systems would issue a port enable to all ports, but
  since the current code only does the special initialization for ICH8M,
  it entirely and rely on BIOS to do the right thing (the alternative
  would be https://reviews.freebsd.org/D18300?id=50922 , should we see
  reports that we really need to do it).
  
  Differential Revision:  https://reviews.freebsd.org/D18300

Modified:
  stable/12/sys/dev/ahci/ahci_pci.c
Directory Properties:
  stable/12/   (props changed)

Modified: stable/12/sys/dev/ahci/ahci_pci.c
==============================================================================
--- stable/12/sys/dev/ahci/ahci_pci.c	Mon Jul  8 10:18:11 2019	(r349830)
+++ stable/12/sys/dev/ahci/ahci_pci.c	Mon Jul  8 10:19:49 2019	(r349831)
@@ -360,10 +360,7 @@ static int
 ahci_pci_ctlr_reset(device_t dev)
 {
 
-	if (pci_read_config(dev, PCIR_DEVVENDOR, 4) == 0x28298086 &&
-	    (pci_read_config(dev, 0x92, 1) & 0xfe) == 0x04)
-		pci_write_config(dev, 0x92, 0x01, 1);
-	return ahci_ctlr_reset(dev);
+	return(ahci_ctlr_reset(dev));
 }
 
 static int