Re: [PATCH v2 3/5] PCI: iproc: Disable MSI parsing in certain PAXC blocks

poza
2018-06-12T08:29:30Z

On 2018-06-12 05:51, Ray Jui wrote:
> The internal MSI parsing logic in certain revisions of PAXC root
> complexes does not work properly and can casue corruptions on the
> writes. They need to be disabled
>
> Signed-off-by: Ray Jui <ray.jui@broadcom.com>
> Reviewed-by: Scott Branden <scott.branden@broadcom.com>
> ---
> drivers/pci/host/pcie-iproc.c | 34 ++++++++++++++++++++++++++++++++--
> 1 file changed, 32 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/pci/host/pcie-iproc.c
> b/drivers/pci/host/pcie-iproc.c
> index 680f6b1..0804aa2 100644
> --- a/drivers/pci/host/pcie-iproc.c
> +++ b/drivers/pci/host/pcie-iproc.c
> @@ -1197,10 +1197,22 @@ static int iproc_pcie_paxb_v2_msi_steer(struct
> iproc_pcie *pcie, u64 msi_addr)
> return ret;
> }
>
> -static void iproc_pcie_paxc_v2_msi_steer(struct iproc_pcie *pcie, u64
> msi_addr)
> +static void iproc_pcie_paxc_v2_msi_steer(struct iproc_pcie *pcie, u64
> msi_addr,
> + bool enable)
> {
> u32 val;
>
> + if (!enable) {
> + /*
> + * Disable PAXC MSI steering. All write transfers will be
> + * treated as non-MSI transfers
> + */
> + val = iproc_pcie_read_reg(pcie, IPROC_PCIE_MSI_EN_CFG);
> + val &= ~MSI_ENABLE_CFG;
> + iproc_pcie_write_reg(pcie, IPROC_PCIE_MSI_EN_CFG, val);
> + return;
can be dropped.
> + }
> +
> /*
> * Program bits [43:13] of address of GITS_TRANSLATER register into
> * bits [30:0] of the MSI base address register. In fact, in all
> iProc
> @@ -1254,7 +1266,7 @@ static int iproc_pcie_msi_steer(struct iproc_pcie
> *pcie,
> return ret;
> break;
> case IPROC_PCIE_PAXC_V2:
> - iproc_pcie_paxc_v2_msi_steer(pcie, msi_addr);
> + iproc_pcie_paxc_v2_msi_steer(pcie, msi_addr, true);
> break;
> default:
> return -EINVAL;
> @@ -1480,6 +1492,24 @@ int iproc_pcie_remove(struct iproc_pcie *pcie)
> }
> EXPORT_SYMBOL(iproc_pcie_remove);
>
> +/*
> + * The MSI parsing logic in certain revisions of Broadcom PAXC based
> root
> + * complex does not work and needs to be disabled
> + */
> +static void quirk_paxc_disable_msi_parsing(struct pci_dev *pdev)
> +{
> + struct iproc_pcie *pcie = iproc_data(pdev->bus);
> +
> + if (pdev->hdr_type == PCI_HEADER_TYPE_BRIDGE)
> + iproc_pcie_paxc_v2_msi_steer(pcie, 0, false);
> +}
> +DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_BROADCOM, 0x16f0,
> + quirk_paxc_disable_msi_parsing);
> +DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_BROADCOM, 0xd802,
> + quirk_paxc_disable_msi_parsing);
> +DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_BROADCOM, 0xd804,
> + quirk_paxc_disable_msi_parsing);
> +
> MODULE_AUTHOR("Ray Jui <rjui@broadcom.com>");
> MODULE_DESCRIPTION("Broadcom iPROC PCIe common driver");
> MODULE_LICENSE("GPL v2");