On Fri, Sep 23, 2016 at 02:41:39PM -0400, Christopher Covington wrote:

On 09/22/2016 07:08 PM, Bjorn Helgaas wrote:

quoted

On Wed, Sep 21, 2016 at 06:40:47PM -0400, Christopher Covington wrote:

quoted

Hi Bjorn,

On 09/21/2016 09:11 AM, Bjorn Helgaas wrote:

quoted

On Tue, Sep 20, 2016 at 09:15:14PM -0400, cov at codeaurora.org wrote:

quoted

quoted

quoted

diff --git a/drivers/acpi/pci_mcfg.c b/drivers/acpi/pci_mcfg.c
index eb14f74..bb3b8ad 100644
--- a/drivers/acpi/pci_mcfg.c
+++ b/drivers/acpi/pci_mcfg.c

@@ -42,86 +42,59 @@ struct mcfg_fixup {

	struct resource cfgres;
};

-#define MCFG_DOM_ANY			(-1)

Did you delete this because there were no current users, because you'd
prefer users just use "-1", or for some other reason?

I removed it because there were no users of it and, more importantly,
the code doesn't implement support for it.

It looks like a stale "First match against PCI topology <domain:bus>..."
comment remains.

Yep.  I removed the comment since it's sort of obvious from the code.
I also renamed a few things and pulled the match out into a helper
function.

I also changed the dmesg note: I think the actual resource and the
name of the pci_ecam_ops is more interesting than the table IDs (which
I think are already elsewhere in the dmesg log).

It looks like the resource is already being printed from
drivers/pci/ecam.c:102.

Yes, but I want a hint that a quirk has overridden it because that's a
clue that there's something wonky about the platform or the firmware.

But I guess it'd be nice to mirror the format of the existing info
(mem first, then bus range).

quoted

Here's the incremental diff, which I can't really test:

Here's what it looks like for me:

ACPI: PCI Root Bridge [PCI2] (domain 0002 [bus 00-1f])
acpi PNP0A08:02: _OSC: OS supports [ExtendedConfig ASPM ClockPM Segments MSI]
acpi PNP0A08:02: _OSC: platform does not support [PCIeHotplug]
acpi PNP0A08:02: _OSC: OS now controls [PME AER PCIeCapability]
acpi PNP0A08:02: MCFG quirk: ECAM space for [bus 00-1f] at [mem 0xa0000000000-0xa0001ffffff] with pci_3

Is "pci_3" really the entire name?  If not, what happened to the rest?
I was hoping for a symbol we could grep for.

acpi PNP0A08:02: ECAM at [mem 0xa0000000000-0xa0001ffffff] for [bus 00-1f]
Remapped I/O 0x00000affffff0000 to [io  0x10000-0x1ffff window]
PCI host bridge to bus 0002:00

quoted

diff --git a/drivers/acpi/pci_mcfg.c b/drivers/acpi/pci_mcfg.c
index 245b79f..0b36bc5 100644
--- a/drivers/acpi/pci_mcfg.c
+++ b/drivers/acpi/pci_mcfg.c

@@ -36,7 +36,7 @@ struct mcfg_fixup {
 	char oem_id[ACPI_OEM_ID_SIZE + 1];
 	char oem_table_id[ACPI_OEM_TABLE_ID_SIZE + 1];
 	u32 oem_revision;
-	u16 seg;
+	u16 segment;
 	struct resource bus_range;
 	struct pci_ecam_ops *ops;
 	struct resource cfgres;

@@ -102,30 +102,37 @@ static char mcfg_oem_id[ACPI_OEM_ID_SIZE];
 static char mcfg_oem_table_id[ACPI_OEM_TABLE_ID_SIZE];
 static u32 mcfg_oem_revision;
 
-static void pci_mcfg_match_quirks(struct acpi_pci_root *root,
+static int pci_mcfg_quirk_matches(struct mcfg_fixup *f, u16 segment,
+				  struct resource *bus_range)
+{
+	if (!memcmp(f->oem_id, mcfg_oem_id, ACPI_OEM_ID_SIZE) &&
+	    !memcmp(f->oem_table_id, mcfg_oem_table_id,
+	            ACPI_OEM_TABLE_ID_SIZE) &&
+	    f->oem_revision == mcfg_oem_revision &&
+	    f->segment == segment &&
+	    resource_contains(&f->bus_range, bus_range))
+		return 1;
+
+	return 0;
+}
+
+static void pci_mcfg_apply_quirks(struct acpi_pci_root *root,
 				  struct resource *cfgres,
 				  struct pci_ecam_ops **ecam_ops)
 {
+	u16 segment = root->segment;
+	struct resource *bus_range = &root->secondary;
 	struct mcfg_fixup *f;
 	int i;
 
-	/*
-	 * First match against PCI topology <domain:bus> then use OEM ID, OEM
-	 * table ID, and OEM revision from MCFG table standard header.
-	 */
 	for (i = 0, f = mcfg_quirks; i < ARRAY_SIZE(mcfg_quirks); i++, f++) {
-		if (!memcmp(f->oem_id, mcfg_oem_id, ACPI_OEM_ID_SIZE) &&
-		    !memcmp(f->oem_table_id, mcfg_oem_table_id,
-		            ACPI_OEM_TABLE_ID_SIZE) &&
-		    f->oem_revision == mcfg_oem_revision &&
-		    f->seg == root->segment &&
-		    resource_contains(&f->bus_range, &root->secondary)) {
+		if (pci_mcfg_quirk_matches(f, segment, bus_range)) {
 			if (f->cfgres.start)
 				*cfgres = f->cfgres;
 			if (f->ops)
 				*ecam_ops =  f->ops;
-			dev_info(&root->device->dev, "Applying PCI MCFG quirks for %s %s rev: %d\n",
-				 f->oem_id, f->oem_table_id, f->oem_revision);
+			dev_info(&root->device->dev, "MCFG quirk: ECAM space for %pR at %pR with %ps\n",
+				 bus_range, cfgres, *ecam_ops);
 			return;
 		}
 	}

@@ -173,7 +180,7 @@ skip_lookup:
 	 * MCFG does not have it.  Invalid CFG start address means MCFG
 	 * firmware bug or we need another quirk in array.
 	 */
-	pci_mcfg_match_quirks(root, &res, &ops);
+	pci_mcfg_apply_quirks(root, &res, &ops);
 	if (!res.start)
 		return -ENXIO;
 

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