Re: [PATCH v6 02/18] PCI: designware-ep: dw_pcie_ep_set_msi() should only set MMC bits
From: Joao Pinto
Date: Wed Dec 20 2017 - 14:18:06 EST
Hi,
Ãs 11:29 PM de 12/19/2017, Niklas Cassel escreveu:
> Previously, dw_pcie_ep_set_msi() wrote all bits in the Message Control
> register, thus overwriting the PCI_MSI_FLAGS_64BIT bit.
> By clearing the PCI_MSI_FLAGS_64BIT bit, we break MSI
> on systems where the RC has set a 64 bit MSI address.
> Fix dw_pcie_ep_set_msi() so that it only sets MMC bits.
>
> Signed-off-by: Niklas Cassel <niklas.cassel@xxxxxxxx>
> ---
> drivers/pci/dwc/pcie-designware-ep.c | 4 +++-
> drivers/pci/dwc/pcie-designware.h | 1 +
> 2 files changed, 4 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/pci/dwc/pcie-designware-ep.c b/drivers/pci/dwc/pcie-designware-ep.c
> index d53d5f168363..c92ab87fd660 100644
> --- a/drivers/pci/dwc/pcie-designware-ep.c
> +++ b/drivers/pci/dwc/pcie-designware-ep.c
> @@ -220,7 +220,9 @@ static int dw_pcie_ep_set_msi(struct pci_epc *epc, u8 encode_int)
> struct dw_pcie_ep *ep = epc_get_drvdata(epc);
> struct dw_pcie *pci = to_dw_pcie_from_ep(ep);
>
> - val = (encode_int << MSI_CAP_MMC_SHIFT);
> + val = dw_pcie_readw_dbi(pci, MSI_MESSAGE_CONTROL);
> + val &= ~MSI_CAP_MMC_MASK;
> + val |= (encode_int << MSI_CAP_MMC_SHIFT) & MSI_CAP_MMC_MASK;
> dw_pcie_writew_dbi(pci, MSI_MESSAGE_CONTROL, val);
>
> return 0;
> diff --git a/drivers/pci/dwc/pcie-designware.h b/drivers/pci/dwc/pcie-designware.h
> index ecdede68522a..9aaf0cd04dd6 100644
> --- a/drivers/pci/dwc/pcie-designware.h
> +++ b/drivers/pci/dwc/pcie-designware.h
> @@ -101,6 +101,7 @@
>
> #define MSI_MESSAGE_CONTROL 0x52
> #define MSI_CAP_MMC_SHIFT 1
> +#define MSI_CAP_MMC_MASK (7 << MSI_CAP_MMC_SHIFT)
> #define MSI_CAP_MME_SHIFT 4
> #define MSI_CAP_MME_MASK (7 << MSI_CAP_MME_SHIFT)
> #define MSI_MESSAGE_ADDR_L32 0x54
>
Acked-by: Joao Pinto <jpinto@xxxxxxxxxxxx>