Re: [PATCH 2/2] PCI: imx6: limit DBI register length

From: Leonard Crestez
Date: Tue Nov 20 2018 - 05:23:04 EST


On Mon, 2018-11-19 at 10:41 +0100, Stefan Agner wrote:
> 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:
> # cat /sys/devices/soc0/soc/1ffc000.pcie/pci0000\:00/0000\:00\:00.0/config
> [ 100.021433] Unhandled fault: imprecise external abort (0x1406) at 0xb6ea7000
> ...
> [ 100.056423] PC is at dw_pcie_read+0x50/0x84
> [ 100.060790] LR is at dw_pcie_rd_own_conf+0x44/0x48
> ...
>
> Signed-off-by: Stefan Agner <stefan@xxxxxxxx>
>
> diff --git a/drivers/pci/controller/dwc/pci-imx6.c

> +struct imx6_pcie_drvdata {
> + enum imx6_pcie_variants variant;
> + int dbi_length;
> +};

Turning imx6_pcie drvdata into a struct is very nice, maybe in the
future some of the long case statements in this driver could be split
into per-soc functions called via drvdata.