Re: [PATCH v2 3/3] PCI: imx6: limit DBI register length

[Lucas Stach]

Am Dienstag, den 20.11.2018, 14:27 +0100 schrieb Stefan Agner:
> Define the length of the DBI registers. This makes sure that
> the kernel does not access registers beyond that point, avoiding
> the following abort on a i.MX 6Quad:
> Â # cat /sys/devices/soc0/soc/1ffc000.pcie/pci0000\:00/0000\:00\:00.0/config
> Â [ÂÂ100.021433] Unhandled fault: imprecise external abort (0x1406) at 0xb6ea7000
> Â ...
> Â [ÂÂ100.056423] PC is at dw_pcie_read+0x50/0x84
> Â [ÂÂ100.060790] LR is at dw_pcie_rd_own_conf+0x44/0x48
> Â ...
> 
> Signed-off-by: Stefan Agner <stefan@xxxxxxxx>

Reviewed-by: Lucas Stach <l.stach@xxxxxxxxxxxxxx>

> ---
> Âdrivers/pci/controller/dwc/pci-imx6.c | 5 ++++-
> Â1 file changed, 4 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/pci/controller/dwc/pci-imx6.c b/drivers/pci/controller/dwc/pci-imx6.c
> index 7ac1a639fe91..41d6127b40ad 100644
> --- a/drivers/pci/controller/dwc/pci-imx6.c
> +++ b/drivers/pci/controller/dwc/pci-imx6.c
> @@ -41,6 +41,7 @@ enum imx6_pcie_variants {
> Â
> Âstruct imx6_pcie_drvdata {
> > Â	enum imx6_pcie_variants variant;
> > > +	int			dbi_length;
> Â};
> Â
> Âstruct imx6_pcie {
> @@ -779,6 +780,8 @@ static int imx6_pcie_probe(struct platform_device *pdev)
> > Â		break;
> > Â	}
> Â
> > +	pci->dbi_length = imx6_pcie->drvdata->dbi_length;
> +
> > Â	/* Grab GPR config register range */
> > Â	imx6_pcie->iomuxc_gpr =
> > Â		Âsyscon_regmap_lookup_by_compatible("fsl,imx6q-iomuxc-gpr");
> @@ -839,7 +842,7 @@ static void imx6_pcie_shutdown(struct platform_device *pdev)
> Â}
> Â
> Âstatic const struct imx6_pcie_drvdata drvdata[] = {
> > -	[IMX6Q] = { .variant = IMX6Q },
> > +	[IMX6Q] = { .variant = IMX6Q, .dbi_length = 0x15c },
> > Â	[IMX6SX] = { .variant = IMX6SX },
> > Â	[IMX6QP] = { .variant = IMX6QP },
> > Â	[IMX7D] = { .variant = IMX7D },