Commit 1dec6b05 authored by Yinghai Lu's avatar Yinghai Lu Committed by Jesse Barnes
Browse files

PCI: don't enable too many HT MSI mappings 



Prakash reported that his c51-mcp51 ondie sound card doesn't work with
MSI.  But if he hacks out the HT-MSI quirk, MSI works fine.

So this patch reworks the nv_msi_ht_cap_quirk().  It will now only
enable ht_msi on own its root device, avoiding enabling it on devices
following that root dev.

Reported-by: default avatarPrakash Punnoor <prakash@punnoor.de>
Tested-by: default avatarPrakash Punnoor <prakash@punnoor.de>
Signed-off-by: default avatarYinghai Lu <yinghai@kernel.org>
Signed-off-by: default avatarJesse Barnes <jbarnes@hobbes.lan>
parent d22157b3

drivers/pci/quirks.c

+100 −15
Original line number Diff line number Diff line
@@ -2050,10 +2050,100 @@ DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_NVIDIA, 
			PCI_DEVICE_ID_NVIDIA_NVENET_15,

			nvenet_msi_disable);



static void __devinit nv_msi_ht_cap_quirk(struct pci_dev *dev)

static void __devinit nv_ht_enable_msi_mapping(struct pci_dev *dev)

{

	struct pci_dev *host_bridge;

	int pos;

	int i, dev_no;

	int found = 0;



	dev_no = dev->devfn >> 3;

	for (i = dev_no; i >= 0; i--) {

		host_bridge = pci_get_slot(dev->bus, PCI_DEVFN(i, 0));

		if (!host_bridge)

			continue;



		pos = pci_find_ht_capability(host_bridge, HT_CAPTYPE_SLAVE);

		if (pos != 0) {

			found = 1;

			break;

		}

		pci_dev_put(host_bridge);

	}



	if (!found)

		return;



	/* root did that ! */

	if (msi_ht_cap_enabled(host_bridge))

		goto out;



	ht_enable_msi_mapping(dev);



out:

	pci_dev_put(host_bridge);

}



static void __devinit ht_disable_msi_mapping(struct pci_dev *dev)

{

	int pos, ttl = 48;



	pos = pci_find_ht_capability(dev, HT_CAPTYPE_MSI_MAPPING);

	while (pos && ttl--) {

		u8 flags;



		if (pci_read_config_byte(dev, pos + HT_MSI_FLAGS,

					 &flags) == 0) {

			dev_info(&dev->dev, "Enabling HT MSI Mapping\n");



			pci_write_config_byte(dev, pos + HT_MSI_FLAGS,

					      flags & ~HT_MSI_FLAGS_ENABLE);

		}

		pos = pci_find_next_ht_capability(dev, pos,

						  HT_CAPTYPE_MSI_MAPPING);

	}

}



static int __devinit ht_check_msi_mapping(struct pci_dev *dev)

{

	int pos, ttl = 48;

	int found = 0;



	/* check if there is HT MSI cap or enabled on this device */

	pos = pci_find_ht_capability(dev, HT_CAPTYPE_MSI_MAPPING);

	while (pos && ttl--) {

		u8 flags;



		if (found < 1)

			found = 1;

		if (pci_read_config_byte(dev, pos + HT_MSI_FLAGS,

					 &flags) == 0) {

			if (flags & HT_MSI_FLAGS_ENABLE) {

				if (found < 2) {

					found = 2;

					break;

				}

			}

		}

		pos = pci_find_next_ht_capability(dev, pos,

						  HT_CAPTYPE_MSI_MAPPING);

	}



	return found;

}



static void __devinit nv_msi_ht_cap_quirk(struct pci_dev *dev)

{

	struct pci_dev *host_bridge;

	int pos;

	int found;



	/* check if there is HT MSI cap or enabled on this device */

	found = ht_check_msi_mapping(dev);



	/* no HT MSI CAP */

	if (found == 0)

		return;



	/*

	 * HT MSI mapping should be disabled on devices that are below
@@ -2069,24 +2159,19 @@ static void __devinit nv_msi_ht_cap_quirk(struct pci_dev *dev) 
	pos = pci_find_ht_capability(host_bridge, HT_CAPTYPE_SLAVE);

	if (pos != 0) {

		/* Host bridge is to HT */

		ht_enable_msi_mapping(dev);

		if (found == 1) {

			/* it is not enabled, try to enable it */

			nv_ht_enable_msi_mapping(dev);

		}

		return;

	}



	/* Host bridge is not to HT, disable HT MSI mapping on this device */

	pos = pci_find_ht_capability(dev, HT_CAPTYPE_MSI_MAPPING);

	while (pos && ttl--) {

		u8 flags;

	/* HT MSI is not enabled */

	if (found == 1)

		return;



		if (pci_read_config_byte(dev, pos + HT_MSI_FLAGS,

					 &flags) == 0) {

			dev_info(&dev->dev, "Disabling HT MSI mapping");

			pci_write_config_byte(dev, pos + HT_MSI_FLAGS,

					      flags & ~HT_MSI_FLAGS_ENABLE);

		}

		pos = pci_find_next_ht_capability(dev, pos,

						  HT_CAPTYPE_MSI_MAPPING);

	}

	/* Host bridge is not to HT, disable HT MSI mapping on this device */

	ht_disable_msi_mapping(dev);

}

DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_NVIDIA, PCI_ANY_ID, nv_msi_ht_cap_quirk);

DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_AL, PCI_ANY_ID, nv_msi_ht_cap_quirk);

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