From mboxrd@z Thu Jan 1 00:00:00 1970 From: Anatolij Gustschin Date: Tue, 2 Nov 2010 10:18:10 +0100 Subject: [U-Boot] Add video support for mx51evk In-Reply-To: <4CCFB244.2000909@denx.de> References: <6D46366820216241BB9459D07B269372D2D9BE@039-SN1MPN1-002.039d.mgd.msft.net> <4CCFB244.2000909@denx.de> Message-ID: <20101102101810.020df6e6@wker> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: u-boot@lists.denx.de Hi, On Tue, 02 Nov 2010 07:40:04 +0100 Stefano Babic wrote: ... > > There is also a second issue where I would like to know your thoughts. Very > > early on system initialization, when LCD is enabled, there is a call to > > "lcd_setmem" from board.c. By that time, the video variables, > > "panel_info", are > > not set yet. Thus U-Boot doesn't reserve the appropriate amount of > > memory for > > the display. I was going to set "panel_info" variable on mx51evk.c, but > > I would like to know how you solved it for vision2 first. > > Thanks for pointing out, I have already seen the point, but at the end I > forget to fix it ;-). Probably because there is no side-effects on this > board, but this does not mean that the issue should not fixed for > vision2, too. > > The problem arises from the fact that the setup of the display > parameters was static and everything was solved at compile time. With > the framebuffer for the MX51, I needed the possibility to change > dinamically the parameters, because the board can have different LCD > displays. > > Consider this, I do not think the actual computation in lcd_setmem() is > correct. We need to compute the maximum amount of memory to be reserved > to the framebuffer, not the value requested by the current display > interface. We could add a CONFIG_SYS_VIDEO_SIZE that contains the > maximum amount of memory needed, because the value is strictly > board-dependent, and change lcd_setmem to use it. Anatolij, what do you > think about this ? We should reserve the amount of memory we actually need for the used display configuration, I think. Reserving the maximum amount would be needed if we have to support switching the display resolution at runtime, but I don't think that this is needed in your case. Therefore I prefer the solution that reserves the actually needed amount of memory. Best regards, Anatolij