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

From: Stefan Agner
Date: Tue Nov 20 2018 - 05:30:41 EST


On 20.11.2018 11:22, Leonard Crestez wrote:
> 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.

Yeah I thought that too. At a quick glance I did not saw an obvious
contender. Should certainly help for similar cases in the future.

--
Stefan