Den 29.08.2022 15.11, skrev Maxime Ripard:
> Hi,
>
>
>
> Here's a series aiming at improving the command line named modes support,
>
> and more importantly how we deal with all the analog TV variants.
>
>
>
> The named modes support were initially introduced to allow to specify the
>
> analog TV mode to be used.
>
>
>
> However, this was causing multiple issues:
>
>
>
> * The mode name parsed on the command line was passed directly to the
>
> driver, which had to figure out which mode it was suppose to match;
>
>
>
> * Figuring that out wasn't really easy, since the video= argument or what
>
> the userspace might not even have a name in the first place, but
>
> instead could have passed a mode with the same timings;
>
>
>
> * The fallback to matching on the timings was mostly working as long as
>
> we were supporting one 525 lines (most likely NSTC) and one 625 lines
>
> (PAL), but couldn't differentiate between two modes with the same
>
> timings (NTSC vs PAL-M vs NSTC-J for example);
>
>
>
> * There was also some overlap with the tv mode property registered by
>
> drm_mode_create_tv_properties(), but named modes weren't interacting
>
> with that property at all.
>
>
>
> * Even though that property was generic, its possible values were
>
> specific to each drivers, which made some generic support difficult.
>
>
>
> Thus, I chose to tackle in multiple steps:
>
>
>
> * A new TV norm property was introduced, with generic values, each driver
>
> reporting through a bitmask what standard it supports to the userspace;
>
>
>
> * This option was added to the command line parsing code to be able to
>
> specify it on the kernel command line, and new atomic_check and reset
>
> helpers were created to integrate properly into atomic KMS;
>
>
>
> * The named mode parsing code is now creating a proper display mode for
>
> the given named mode, and the TV standard will thus be part of the
>
> connector state;
>
>
>
> * Two drivers were converted and tested for now (vc4 and sun4i), with
>
> some backward compatibility code to translate the old TV mode to the
>
> new TV mode;
>
>
>
> Unit tests were created along the way.
>
>
>
> One can switch from NTSC to PAL now using (on vc4)
>
>
>
> modetest -M vc4 -s 53:720x480i -w 53:'tv norm':0
>
>
>
> modetest -M vc4 -s 53:720x480i -w 53:'tv norm':4
>
The property name has changed, this gives me PAL:
$ modetest -M vc4 -s 45:720x576i -w 45:'TV mode':4
I have finally found a workaround for my kernel hangs.
Dom had a look at my kernel and found that the VideoCore was fine, and
he said this:
> That suggests cause of lockup was on arm side rather than VC side.
>
> But it's hard to diagnose further. Once you've had a peripheral not
> respond, the AXI bus locks up and no further operations are possible.
> Usual causes of this are required clocks being stopped or domains
> disabled and then trying to access the hardware.
>
So when I got this on my 64-bit build:
[ 166.702171] SError Interrupt on CPU1, code 0x00000000bf000002 -- SError
[ 166.702187] CPU: 1 PID: 8 Comm: kworker/u8:0 Tainted: G W
5.19.0-rc6-00096-gba7973977976-dirty #1
[ 166.702200] Hardware name: Raspberry Pi 4 Model B Rev 1.1 (DT)
[ 166.702206] Workqueue: events_freezable_power_ thermal_zone_device_check
[ 166.702231] pstate: 200000c5 (nzCv daIF -PAN -UAO -TCO -DIT -SSBS
BTYPE=--)
[ 166.702242] pc : regmap_mmio_read32le+0x10/0x28
[ 166.702261] lr : regmap_mmio_read+0x44/0x70
...
[ 166.702606] bcm2711_get_temp+0x58/0xb0 [bcm2711_thermal]
I wondered if that reg read was stalled due to a clock being stopped.
Lo and behold, disabling runtime pm and keeping the vec clock running
all the time fixed it[1].
I don't know what the problem is, but at least I can now test this patchset.
[1] https://gist.github.com/notro/23b984e7fa05cfbda2db50a421cac065
Noralf.
