i915 with valleyview

i915 with valleyview

[Sudip Mukherjee]

Hi Daniel,
I am trying to use i915 in one of our board which has Intel ATOM E3840.
I know Intel has released emgd driver for this cpu to use i915 but emgd
is not supported on v4.5 (or v4.6). The board is having SFI (simple
firmware interface) and maybe for that i915 is not finding the VBIOS and
other required information. I have turned on drm debugging and some
parts of it are:
[    0.390846] [drm] Initialized drm 1.1.0 20060810
[    0.390875] i915 0000:00:02.0: PCI->APIC IRQ transform: INT A -> IRQ 16
<snip>
[    0.391595] [drm:i915_dump_device_info] i915 device info: gen=7, pciid=0x0f31 rev=0x0a flags=is_mobile,need_gfx_hws,is_valleyview,has_hotplug,
[    0.391615] [drm:intel_detect_pch] No PCH found.
[    0.391760] [drm] Memory usable by graphics device = 2048M
[    0.391764] [drm:i915_gem_gtt_init] GMADR size = 256M
[    0.391767] [drm:i915_gem_gtt_init] GTT stolen size = 64M
[    0.391770] [drm:sanitize_enable_ppgtt] disabling PPGTT on pre-B3 step VLV

I can see that four connectors are registered. But I am also seeing-

[    2.143214] [drm:intel_crt_detect] [CONNECTOR:29:VGA-1] force=1
[    2.143216] [drm:intel_power_well_enable] enabling display
[    2.149314] [drm:i915_redisable_vga_power_on] Something enabled VGA plane, disabling it
[    2.149627] [drm:intel_power_well_enable] enabling dpio-common
[    2.157670] [drm:valleyview_crt_detect_hotplug] trigger hotplug detect cycle: adpa=0x40000
[    2.161690] [drm:valleyview_crt_detect_hotplug] valleyview hotplug adpa=0x40000, result 0
[    2.161692] [drm:intel_crt_detect] CRT not detected via hotplug
[    2.168780] [drm:drm_do_probe_ddc_edid] drm: skipping non-existent adapter i915 gmbus vga
[    2.168782] [drm:intel_crt_detect_ddc] CRT not detected via DDC:0x50 [no valid EDID found]
[    2.168783] [drm:intel_power_well_disable] disabling dpio-common
[    2.176832] [drm:intel_power_well_disable] disabling display
[    2.186894] [drm:drm_helper_probe_single_connector_modes_merge_bits] [CONNECTOR:29:VGA-1] disconnected

Same thing happens for all the other connectors.

I will greatly appreciate any help or pointer to something which can
make i915 work in this scenario. Maybe there is some option where I can
provide the configuration to i915 manually rather than depending on
hotplog/edid or some other way which I am missing.

Regards
Sudip
_______________________________________________
dri-devel mailing list
dri-devel@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/dri-devel

Re: i915 with valleyview

[Sudip Mukherjee]

On Fri, May 06, 2016 at 12:21:04PM +0100, Sudip Mukherjee wrote:
> Hi Daniel,
> I am trying to use i915 in one of our board which has Intel ATOM E3840.
> I know Intel has released emgd driver for this cpu to use i915 but emgd
> is not supported on v4.5 (or v4.6). The board is having SFI (simple
> firmware interface) and maybe for that i915 is not finding the VBIOS and
> other required information.

I have been looking more into it and looks like it is supposed to use
dsi but since there is no vbt so has_mipi is never set and dsi is never
initialized.
Can you please point me to somewhere or maybe give some idea how i can
use i915 in a board where there is no vbt.

Regards
Sudip
_______________________________________________
dri-devel mailing list
dri-devel@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/dri-devel

Re: i915 with valleyview

[Jani Nikula]

On Fri, 06 May 2016, Sudip Mukherjee <sudipm.mukherjee@gmail.com> wrote:
> On Fri, May 06, 2016 at 12:21:04PM +0100, Sudip Mukherjee wrote:
>> Hi Daniel,
>> I am trying to use i915 in one of our board which has Intel ATOM E3840.
>> I know Intel has released emgd driver for this cpu to use i915 but emgd
>> is not supported on v4.5 (or v4.6). The board is having SFI (simple
>> firmware interface) and maybe for that i915 is not finding the VBIOS and
>> other required information.
>
> I have been looking more into it and looks like it is supposed to use
> dsi but since there is no vbt so has_mipi is never set and dsi is never
> initialized.
> Can you please point me to somewhere or maybe give some idea how i can
> use i915 in a board where there is no vbt.

Hate to say it, but the i915 DSI support heavily relies on the VBT being
present. Basically all the configuration is there. I haven't got a clue
how emgd handles it. Maybe Matt does?

Basically you'd either have to figure out the configuration for the
panel from somewhere and feed it to intel_dsi_panel_vbt.c, or write a
panel specific driver of your own.

BR,
Jani.


-- 
Jani Nikula, Intel Open Source Technology Center
_______________________________________________
dri-devel mailing list
dri-devel@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/dri-devel

Re: i915 with valleyview

[Sudip Mukherjee]

On Mon, May 09, 2016 at 11:19:16AM +0300, Jani Nikula wrote:
> On Fri, 06 May 2016, Sudip Mukherjee <sudipm.mukherjee@gmail.com> wrote:
> > On Fri, May 06, 2016 at 12:21:04PM +0100, Sudip Mukherjee wrote:
> >> Hi Daniel,
> >> I am trying to use i915 in one of our board which has Intel ATOM E3840.
> >> I know Intel has released emgd driver for this cpu to use i915 but emgd
> >> is not supported on v4.5 (or v4.6). The board is having SFI (simple
> >> firmware interface) and maybe for that i915 is not finding the VBIOS and
> >> other required information.
> >
> > I have been looking more into it and looks like it is supposed to use
> > dsi but since there is no vbt so has_mipi is never set and dsi is never
> > initialized.
> > Can you please point me to somewhere or maybe give some idea how i can
> > use i915 in a board where there is no vbt.
> 
> Hate to say it, but the i915 DSI support heavily relies on the VBT being
> present. Basically all the configuration is there. I haven't got a clue
> how emgd handles it. Maybe Matt does?

emgd has a config file where we have to specify the configuration for
it to work.

> 
> Basically you'd either have to figure out the configuration for the
> panel from somewhere and feed it to intel_dsi_panel_vbt.c, or write a
> panel specific driver of your own.

and i guess i will also need to modify intel_dsi_init() as that is also
taking some of the information from the VBT.

Thanks for the information.

regards
sudip
_______________________________________________
dri-devel mailing list
dri-devel@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/dri-devel