Re: [PATCH v6 2/3] drm/i915/display: Restructure output format computation for better expandability

From: Randy Dunlap <rdunlap@infradead.org>
To: "Ville Syrjälä" <ville.syrjala@linux.intel.com>,
	"Werner Sembach" <wse@tuxedocomputers.com>
Cc: airlied@linux.ie, daniel@ffwll.ch,
	intel-gfx@lists.freedesktop.org, dri-devel@lists.freedesktop.org,
	linux-kernel@vger.kernel.org
Subject: Re: [PATCH v6 2/3] drm/i915/display: Restructure output format computation for better expandability
Date: Fri, 7 May 2021 10:56:34 -0700	[thread overview]
Message-ID: <0d88cd48-a91f-bf0a-e298-a9d66bf0562b@infradead.org> (raw)
In-Reply-To: <YJV+Xr59xyK2yLXT@intel.com>

On 5/7/21 10:52 AM, Ville Syrjälä wrote:
> On Fri, May 07, 2021 at 10:49:02AM +0200, Werner Sembach wrote:
>> Couples the decission between RGB and YCbCr420 mode and the check if the
>> port clock can archive the required frequency. Other checks and
>> configuration steps that where previously done in between can also be done
>> before or after.
>>
>> This allows for are cleaner implementation of retrying different color
>> encodings.
>>
>> A slight change in behaviour occurs with this patch: If YCbCr420 is not
>> allowed but display is YCbCr420 only it no longer fails, but just prints
>> an error and tries to fallback on RGB.
>>
>> Signed-off-by: Werner Sembach <wse@tuxedocomputers.com>
>> ---
>>  drivers/gpu/drm/i915/display/intel_hdmi.c | 65 ++++++++++++-----------
>>  1 file changed, 34 insertions(+), 31 deletions(-)
>>

> 
> We can't let the user spam dmesg with errors freely. So this needs
> to be a drm_dbg_kms(). Also a bit long, so going to annoyingly wrap
> always. Could maybe shorten a bit to something like:
> "YCbCr 4:2:0 mode but YCbCr 4:2:0 output not possible. Falling back to RGB."
> 
> With that sorted, and the intel_hdmi_port_clock() stuff restored,
> I believe this series is good to go.
> 
> I think you confused our CI by replying to the old patch with a whole
> new series. It can generally deal with a whole new series as a new
> thread or replies to individual patches with updated versions of
> exactly that patch, but not full series as a reply to a patch.
> So I suggest just posting the final versions as a new series. Thanks.
> 

Yeah, we try to say "don't do that," but maybe we need to say that more
strongly. See Documentation/process/submitting-patches.rst:

<<<
However, for a multi-patch series, it is generally
best to avoid using In-Reply-To: to link to older versions of the
series.  This way multiple versions of the patch don't become an
unmanageable forest of references in email clients.  If a link is
helpful, you can use the https://lkml.kernel.org/ redirector (e.g., in
the cover email text) to link to an earlier version of the patch series.
>>>

-- 
~Randy