Re: [PATCH 3/3] drm: omapdrm: Do no allocate non-scanout GEMs through DMM/TILER

From: Ivaylo Dimitrov
Date: Mon Oct 31 2022 - 06:31:14 EST




On 31.10.22 г. 12:13 ч., Tony Lindgren wrote:
* Ivaylo Dimitrov <ivo.g.dimitrov.75@xxxxxxxxx> [221031 06:55]:
On 31.10.22 г. 0:08 ч., H. Nikolaus Schaller wrote:
[ 39.419846] WARNING: CPU: 0 PID: 3673 at drivers/bus/omap_l3_noc.c:139 l3_interrupt_handler+0x23c/0x330
[ 39.429914] 44000000.l3-noc:L3 Custom Error: MASTER MPU TARGET GPMC (Idle): Data Access in Supervisor mode during Functional access
...


I have no idea what that error is supposed to mean. @Tony?

The error above is GPMC related. It means GPMC is not properly clocked or powered
while trying to access it's IO range.

Maybe DSS is somehow trying to access GPMC address space registers with DMA? The
GPMC address space starts at 0. Maybe the DSS DMA address is 0 somwhere?


Seems like, but I can't see how this can happen given that omap_fbdev_create() calls omap_gem_new() with OMAP_BO_SCANOUT. Unless something bad happens in omap_framebuffer_init(), which is called before omap_gem_pin() is called.

Regards,
Ivo

Regards,

Tony