[drm] Reducing the compressed framebuffer size

[Massimo B.]

Hello everybody,

since Kernel 5.6.5 I encounter many syslog lines like

[kernel] [drm] Reducing the compressed framebuffer size. This may lead to less power savings than a non-reduced-size. Try to increase stolen memory size if available in BIOS.
                - Last output repeated 4 times -

I found some explanation at:
https://wiki.archlinux.org/index.php/intel_graphics#Framebuffer_compression_(enable_fbc)
But why do I get this with a i7-4790 Haswell, which is not pre-Sandy?

Anyway I followed the hint and set

# cat /etc/modprobe.d/i915.conf
options i915 enable_fbc=0

After reboot the setting seems active:

# cat /sys/module/i915/parameters/enable_fbc
0

But I still get the same logs. Which BIOS setting is responsible, how can I fix
that? Is there a better place to ask?

# lspci |grep VGA
00:02.0 VGA compatible controller: Intel Corporation Xeon E3-1200 v3/4th Gen Core Processor Integrated Graphics Controller (rev 06)

# grep name /proc/cpuinfo |tail -n1
model name	: Intel(R) Core(TM) i7-4790 CPU @ 3.60GHz

Best regards,
Massimo