Commit 7aae9412 authored by Bjorn Helgaas's avatar Bjorn Helgaas
Browse files

Merge branch 'pci/virtualization' 

- Avoid bus resets on Atheros QCA6174, since they hang (Ingmar Klein)

- Use store and forward mode on Pericom PI7C9X2G switches to avoid ACS
  erratum with ACS P2P Request Redirect (Nathan Rossi)

* pci/virtualization:
  PCI: Add ACS quirk for Pericom PI7C9X2G switches
  PCI: Mark Atheros QCA6174 to avoid bus reset
parents ebf275b8 acd61ffb

drivers/pci/quirks.c

+56 −0
Original line number Diff line number Diff line
@@ -3612,6 +3612,7 @@ DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_ATHEROS, 0x0032, quirk_no_bus_reset); 
DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_ATHEROS, 0x003c, quirk_no_bus_reset);

DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_ATHEROS, 0x0033, quirk_no_bus_reset);

DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_ATHEROS, 0x0034, quirk_no_bus_reset);

DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_ATHEROS, 0x003e, quirk_no_bus_reset);



/*

 * Root port on some Cavium CN8xxx chips do not successfully complete a bus
@@ -5795,3 +5796,58 @@ static void apex_pci_fixup_class(struct pci_dev *pdev) 
}

DECLARE_PCI_FIXUP_CLASS_HEADER(0x1ac1, 0x089a,

			       PCI_CLASS_NOT_DEFINED, 8, apex_pci_fixup_class);



/*

 * Pericom PI7C9X2G404/PI7C9X2G304/PI7C9X2G303 switch erratum E5 -

 * ACS P2P Request Redirect is not functional

 *

 * When ACS P2P Request Redirect is enabled and bandwidth is not balanced

 * between upstream and downstream ports, packets are queued in an internal

 * buffer until CPLD packet. The workaround is to use the switch in store and

 * forward mode.

 */

#define PI7C9X2Gxxx_MODE_REG		0x74

#define PI7C9X2Gxxx_STORE_FORWARD_MODE	BIT(0)

static void pci_fixup_pericom_acs_store_forward(struct pci_dev *pdev)

{

	struct pci_dev *upstream;

	u16 val;



	/* Downstream ports only */

	if (pci_pcie_type(pdev) != PCI_EXP_TYPE_DOWNSTREAM)

		return;



	/* Check for ACS P2P Request Redirect use */

	if (!pdev->acs_cap)

		return;

	pci_read_config_word(pdev, pdev->acs_cap + PCI_ACS_CTRL, &val);

	if (!(val & PCI_ACS_RR))

		return;



	upstream = pci_upstream_bridge(pdev);

	if (!upstream)

		return;



	pci_read_config_word(upstream, PI7C9X2Gxxx_MODE_REG, &val);

	if (!(val & PI7C9X2Gxxx_STORE_FORWARD_MODE)) {

		pci_info(upstream, "Setting PI7C9X2Gxxx store-forward mode to avoid ACS erratum\n");

		pci_write_config_word(upstream, PI7C9X2Gxxx_MODE_REG, val |

				      PI7C9X2Gxxx_STORE_FORWARD_MODE);

	}

}

/*

 * Apply fixup on enable and on resume, in order to apply the fix up whenever

 * ACS configuration changes or switch mode is reset

 */

DECLARE_PCI_FIXUP_ENABLE(PCI_VENDOR_ID_PERICOM, 0x2404,

			 pci_fixup_pericom_acs_store_forward);

DECLARE_PCI_FIXUP_RESUME(PCI_VENDOR_ID_PERICOM, 0x2404,

			 pci_fixup_pericom_acs_store_forward);

DECLARE_PCI_FIXUP_ENABLE(PCI_VENDOR_ID_PERICOM, 0x2304,

			 pci_fixup_pericom_acs_store_forward);

DECLARE_PCI_FIXUP_RESUME(PCI_VENDOR_ID_PERICOM, 0x2304,

			 pci_fixup_pericom_acs_store_forward);

DECLARE_PCI_FIXUP_ENABLE(PCI_VENDOR_ID_PERICOM, 0x2303,

			 pci_fixup_pericom_acs_store_forward);

DECLARE_PCI_FIXUP_RESUME(PCI_VENDOR_ID_PERICOM, 0x2303,

			 pci_fixup_pericom_acs_store_forward);