Re: [PATCH] PCI: dwc: Limit config space size for i.MX6
From: Trent Piepho
Date: Wed Nov 14 2018 - 14:44:21 EST
On Wed, 2018-11-14 at 16:49 +0100, Stefan Agner wrote:
> On 19.10.2018 13:13, Stefan Agner wrote:
> > Reading the full 4k config space through sysfs leads to an
> > external abort. Testing on a platform showed that the upper
> > limit is 512. Limit config space to 512.
>
> Any comment on this patch?
>
> Since other devices use similar quirks, I guess the fix can't be far
> off?
>
> Maybe restricting to the PCI device ID used in i.MX 6 only is too
> restrictive, but I guess better restrictive for now?
To trigger this bug I should read the sysfs "config" file for the PCI
bridge device?
Tested on imx7, no problems.
# hexdump -C /sys/devices/platform/soc/30800000.aips-bus/33800000.pcie/pci0000:00/0000:00:00.0/config
[stuff]
00000130 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 |................|
*
00000400 ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff |................|
*
00000700 76 00 63 01 ff ff ff ff 04 00 00 07 00 f0 f0 1b |v.c.............|
[more stuff]
The bridge on imx7d is 16c3:abcd, same as patch I believe. I do have a
pci-e device connected, unlike the original bug. Maybe that is
related? Or maybe this problem is fixed in imx7d?
> >
> > #define PCI_VENDOR_ID_SYNOPSYS 0x16c3
> > +#define PCI_DEVICE_ID_SYNOPSYS_IMX6 0xabcd
> >
> > #define PCI_VENDOR_ID_VITESSE 0x1725
> > #define PCI_DEVICE_ID_VITESSE_VSC7174 0x7174