Re: kern/51251: ACPI device probe raises NMI

["J. Hannken-Illjes" <hannken%eis.cs.tu-bs.de@localhost>]

The following reply was made to PR kern/51251; it has been noted by GNATS.

From: "J. Hannken-Illjes" <hannken%eis.cs.tu-bs.de@localhost>
To: gnats-bugs%NetBSD.org@localhost
Cc: David Young <dyoung%pobox.com@localhost>
Subject: Re: kern/51251: ACPI device probe raises NMI
Date: Sun, 10 Jul 2016 16:30:22 +0200

 The following diff fixes the problem for me:
 
 Index: acpi_mcfg.c
 ===================================================================
 RCS file: /cvsroot/src/sys/dev/acpi/acpi_mcfg.c,v
 retrieving revision 1.2
 diff -p -u -2 -r1.2 acpi_mcfg.c
 --- acpi_mcfg.c	11 Oct 2015 21:49:22 -0000	1.2
 +++ acpi_mcfg.c	10 Jul 2016 14:26:33 -0000
 @@ -491,5 +491,5 @@ acpimcfg_device_probe(const struct pci_a
  	/* Probe extended configuration space. */
  	if (((reg = pci_conf_read(pc, tag, PCI_CONF_SIZE)) == (pcireg_t)-1) ||
 -	    (alias = acpimcfg_ext_conf_is_aliased(pc, tag))) {
 +	    (reg == 0) || (alias = acpimcfg_ext_conf_is_aliased(pc, tag))) {
  		aprint_debug_dev(acpi_sc->sc_dev,
  		    "MCFG: %03d:%02d:%d: invalid config space "
 @@ -527,4 +527,7 @@ acpimcfg_map_bus(device_t self, pci_chip
  	bus_space_handle_t bsh;
  	bus_addr_t baddr;
 +	pcitag_t tag;
 +	pcireg_t reg;
 +	bool is_e7520_mch;
  	int boff;
  	int last_dev, last_func;
 @@ -570,6 +573,27 @@ acpimcfg_map_bus(device_t self, pci_chip
  	mb->last_probed = pci_make_tag(pc, bus, 0, 0);
  
 +	/*
 +	 * On an Intel E7520 we have to temporarily disable
 +	 * Enhanced Config Access error detection and reporting
 +	 * by setting the appropriate error mask in HI_ERRMASK register.
 +	 *
 +	 * See "Intel E7520 Memory Controller Hub (MCH) Datasheet",
 +	 * Document 303006-002, pg. 82
 +	 */
 +	tag = pci_make_tag(pc, 0, 0, 1);
 +	reg = pci_conf_read(pc, tag, PCI_ID_REG);
 +	is_e7520_mch = (reg ==
 +	    PCI_ID_CODE(PCI_VENDOR_INTEL, PCI_PRODUCT_INTEL_E7525_MCHER));
 +	if (is_e7520_mch) {
 +		reg = pci_conf_read(pc, tag, 0x54);
 +		pci_conf_write(pc, tag, 0x54, reg | 0x20);
 +	}
 +
  	acpimcfg_scan_bus(sc, pc, bus);
  
 +	if (is_e7520_mch) {
 +		pci_conf_write(pc, tag, 0x54, reg);
 +	}
 +
  	/* Unmap extended configration space of all dev/func. */
  	bus_space_unmap(seg->ms_bst, bsh, ACPIMCFG_SIZE_PER_BUS);
 
 Does it qualify for commit?
 
 --
 J. Hannken-Illjes - hannken%eis.cs.tu-bs.de@localhost - TU Braunschweig (Germany)