[U-Boot] [RFC] Migrating iMX LCDIF drivers to Driver Model
Marek, Peng,
Writing to you as you were the main contributors to U-boot mxsfb driver implementation (i.MX23/i.MX28 LCDIF driver).
I was about to start working on it's migration to DM (currently mxsfb is being used on our SoM Colibri iMX7S/D), but found it a bit out-dated (no one introduced any changes for the last 5 years) and maybe it's really does make a sense to fetch and port the latest one from the Linux mainline (in a sake of avoiding divergence in implementation and continue fetching future updates from the Linux kernel).
So there are 2 questions spinning in my mind: 1) In case if you are maybe aware, if there were any intentions to do this migration before? (maybe someone asked similar questions or even send some patches, but didn't manage to upstream that; or did similar stuff in some downstream U-boot forks, whatever). Unfortunately I can't any information regarding this in U-boot ML archives .
2) Will it be OK if I introduce a brand new mxsfb driver (ported from Linux), which will be used only when U-boot is built with CONFIG_DM_VIDEO enabled? Existing mxsfb will be left as it is, so I can be removed easily when full migration to DM is done for all boards that are using this driver.
Simon,
Could you also provide you feedback for 2 (if introducing a brand new dm-enabled driver is a good idea), thanks!
Thanks in advance for you comments/suggestions!
Hi Igor,
On Tue, 16 Apr 2019 12:04:41 +0000 Igor Opaniuk igor.opaniuk@toradex.com wrote: ...
So there are 2 questions spinning in my mind:
- In case if you are maybe aware, if there were any intentions to do
this migration before? (maybe someone asked similar questions or even send some patches, but didn't manage to upstream that; or did similar stuff in some downstream U-boot forks, whatever). Unfortunately I can't any information regarding this in U-boot ML archives .
I'm not aware of any activity migrating this driver to DM_VIDEO. Patches welcome.
- Will it be OK if I introduce a brand new mxsfb driver (ported from
Linux), which will be used only when U-boot is built with CONFIG_DM_VIDEO enabled? Existing mxsfb will be left as it is, so I can be removed easily when full migration to DM is done for all boards that are using this driver.
I have no objections. However I don't know how big is the Linux mxsfb driver, maybe we could reduce not needed code to keep the code size smaller.
-- Anatolij
Hi Anatolij,
Thanks for your feedback!
On Tue, Apr 16, 2019 at 2:31 PM Anatolij Gustschin agust@denx.de wrote:
Hi Igor,
On Tue, 16 Apr 2019 12:04:41 +0000 Igor Opaniuk igor.opaniuk@toradex.com wrote: ...
So there are 2 questions spinning in my mind:
- In case if you are maybe aware, if there were any intentions to do
this migration before? (maybe someone asked similar questions or even send some patches, but didn't manage to upstream that; or did similar stuff in some downstream U-boot forks, whatever). Unfortunately I can't any information regarding this in U-boot ML archives .
I'm not aware of any activity migrating this driver to DM_VIDEO. Patches welcome.
- Will it be OK if I introduce a brand new mxsfb driver (ported from
Linux), which will be used only when U-boot is built with CONFIG_DM_VIDEO enabled? Existing mxsfb will be left as it is, so I can be removed easily when full migration to DM is done for all boards that are using this driver.
I have no objections. However I don't know how big is the Linux mxsfb driver, maybe we could reduce not needed code to keep the code size smaller.
-- Anatolij _______________________________________________ U-Boot mailing list U-Boot@lists.denx.de https://lists.denx.de/listinfo/u-boot
Thanks!
-- Best regards - Freundliche Grüsse - Meilleures salutations
Senior Development Engineer, Igor Opaniuk
Toradex AG Altsagenstrasse 5 | 6048 Horw/Luzern | Switzerland | T: +41 41 500 48 00 (main line)
On Tue, Apr 16, 2019 at 5:36 PM Igor Opaniuk igor.opaniuk@toradex.com wrote:
Marek, Peng,
Writing to you as you were the main contributors to U-boot mxsfb driver implementation (i.MX23/i.MX28 LCDIF driver).
I was about to start working on it's migration to DM (currently mxsfb is being used on our SoM Colibri iMX7S/D), but found it a bit out-dated (no one introduced any changes for the last 5 years) and maybe it's really does make a sense to fetch and port the latest one from the Linux mainline (in a sake of avoiding divergence in implementation and continue fetching future updates from the Linux kernel).
So there are 2 questions spinning in my mind:
- In case if you are maybe aware, if there were any intentions to do
this migration before? (maybe someone asked similar questions or even send some patches, but didn't manage to upstream that; or did similar stuff in some downstream U-boot forks, whatever). Unfortunately I can't any information regarding this in U-boot ML archives .
- Will it be OK if I introduce a brand new mxsfb driver (ported from
Linux), which will be used only when U-boot is built with CONFIG_DM_VIDEO enabled? Existing mxsfb will be left as it is, so I can be removed easily when full migration to DM is done for all boards that are using this driver.
How about keeping common code aside and make the existing driver to support dm and non-dm. We can take the required changes on top of dm code if possible, this would be prominent transition instead of having separate code base.
Hi Jagan,
On Tue, Apr 16, 2019 at 2:35 PM Jagan Teki jagan@amarulasolutions.com wrote:
On Tue, Apr 16, 2019 at 5:36 PM Igor Opaniuk igor.opaniuk@toradex.com wrote:
Marek, Peng,
Writing to you as you were the main contributors to U-boot mxsfb driver implementation (i.MX23/i.MX28 LCDIF driver).
I was about to start working on it's migration to DM (currently mxsfb is being used on our SoM Colibri iMX7S/D), but found it a bit out-dated (no one introduced any changes for the last 5 years) and maybe it's really does make a sense to fetch and port the latest one from the Linux mainline (in a sake of avoiding divergence in implementation and continue fetching future updates from the Linux kernel).
So there are 2 questions spinning in my mind:
- In case if you are maybe aware, if there were any intentions to do
this migration before? (maybe someone asked similar questions or even send some patches, but didn't manage to upstream that; or did similar stuff in some downstream U-boot forks, whatever). Unfortunately I can't any information regarding this in U-boot ML archives .
- Will it be OK if I introduce a brand new mxsfb driver (ported from
Linux), which will be used only when U-boot is built with CONFIG_DM_VIDEO enabled? Existing mxsfb will be left as it is, so I can be removed easily when full migration to DM is done for all boards that are using this driver.
How about keeping common code aside and make the existing driver to support dm and non-dm. We can take the required changes on top of dm code if possible, this would be prominent transition instead of having separate code base.
Actually this is what I started doing in the very begging, but the thing is that current mxsfb driver should be fully re-implemented to make it possible. Taking into account that there is already a pretty high divergence between the one in U-boot and another in Linux, I think it's better to sync with the existing mxsfb inthen Linux kernel instead of spending twice much effort on supporting two different implementations in the future.
Anyway legacy stuff supposed to be removed ASAP (when migration is finished), so I really would like to keep the old implementation aside.
U-Boot mailing list U-Boot@lists.denx.de https://lists.denx.de/listinfo/u-boot
participants (3)
-
Anatolij Gustschin -
Igor Opaniuk -
Jagan Teki