Re: [RFC] Dynamic boot logo
From: hinko.kocevar@cetrtapot.si <hidden>
Date: 2007-08-06 12:34:39
Rodolfo Giometti wrote:
On Mon, Aug 06, 2007 at 09:53:24AM +0200, hinko.kocevar@cetrtapot.si wrote:quoted
We would like to have this feature on my embedded system too! Currently we are using bitmap file converted to standard header file and then compiled in the kernel, which is not flexible at all.Yes, I see.quoted
Maybe you could access the same flash memory from the Linux too - using either physical or virtual address space, eg. by I/O or memory mapping it.Yes, I know, but _how_ can I do it? :) In u-boot is very easy but in Linux I still haven't found a good way to do so.
I'm almost certain that your architecture (whatever it may be) uses I/O and/or memory mapped memory for certain purposes. Best way to see how it is done would be to look at the drivers that are used on your architecture. The bottom line is that ioremap() and friends could be used in combination with ioread/iowrite and/or readb/writeb primitives to map and later access the block of memory. If you need some kernel programming pointers try reading Linux device drivers 3 (http://lwn.net/Kernel/LDD3/) or similar book. Also subscribing to the kernelnewbies mailing list could help with kernel basics.
quoted
Another way could be using a dedicated kernel module for the job - eg. you compile the graphic support in the module and the when update is needed only module can be replaced in the file system leaving kernel intact (at least while kernel version does not change).This is not solve the problem, you still need a compilation stage. I wish avoiding it. And, on the other hand, you cannot load a kernel module since you don't mount a root filesystem which is very late during boot.
You are right. I totally missed that part of the procedure although you could use initrd or initramfs for the job (but that does not remove the need to recompile the kernel when new module is being deployed). Regards, Hinko -- ÄŒETRTA POT, d.o.o., Kranj Planina 3 4000 Kranj Slovenia, Europe Tel. +386 (0) 4 280 66 03 E-mail: hinko.kocevar@cetrtapot.si Http: www.cetrtapot.si ------------------------------------------------------------------------- This SF.net email is sponsored by: Splunk Inc. Still grepping through log files to find problems? Stop. Now Search log events and configuration files using AJAX and a browser. Download your FREE copy of Splunk now >> http://get.splunk.com/ _______________________________________________ Linux-fbdev-devel mailing list Linux-fbdev-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/linux-fbdev-devel