2010-09-29 11:08:51     Hiachi TX-09 in 2010R1RC1

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2010-09-29 11:08:51     Hiachi TX-09 in 2010R1RC1

Peter Gombos (HUNGARY)

Message: 93980   




I've just updated our system to 2010R1RC1. I used 2009R1.1RC4 before.


Our board has a Hitachi TX-09 TFT panel. I use the Bluetechnix driver with small modifications (removed some ifdef, changed timers assigned to HSYNC and VSYNC)


The driver worked perfectly in 2009. Now I did the same modifications. The driver successfully initilized. I can open the framebuffer device. After opening I see the timers started, I have exact sync signals. But I can not set the pixels. I put some debug info in the driver and I see the dma_alloc_coherent() function allocated the framebuffer at address 0x03F00000.


But in my application when I call mmap() function after framebuffer open I have a different address (0x02A00000). My application manipulates wrong memory area! If I force my application to use the 0x03F00000 area I get the right picture on the LCD.


I don't understand what happening. I see the framebuffer device registered with the right address but the application receives an other address.




2010-10-01 02:19:05     Re: Hiachi TX-09 in 2010R1RC1

Peter Gombos (HUNGARY)

Message: 94089   


I couldn't find the answer but I could jump over it.


The fb_var_screeninfo structure smem_start item contains the right memory address. Using this address the driver works perfectly. But it is not the right way, I think in a system with MMU I can not write to this area without mmap().


My opinion is that it is uClinux issue and not the driver issue. It is strange that nobody takes care about it...




2010-10-01 03:20:30     Re: Hiachi TX-09 in 2010R1RC1

Michael Hennerich (GERMANY)

Message: 94103    I assume you just copied your modified driver form 2009R1 to trunk/2010R1?


Remove fb_mmap from struct fb_ops.


- .fb_mmap = tx09_fb_mmap,


We added support for get_fb_unmapped_area in include/asm/pgtable.h

This allows you to use the typicall mmap() flags in user space used on fb devices.


/* provide a special get_unmapped_area for framebuffer mmaps of nommu */

extern unsigned long get_fb_unmapped_area(struct file *filp, unsigned long,

unsigned long, unsigned long,

unsigned long);







2010-10-06 03:03:52     Re: Hiachi TX-09 in 2010R1RC1

Mike Frysinger (UNITED STATES)

Message: 94220   


we never use/test this driver.  so it isnt strange at all that we havent seen problems with this device.




2010-10-06 03:04:37     Re: Hiachi TX-09 in 2010R1RC1

Mike Frysinger (UNITED STATES)

Message: 94221   


the 2010R1/trunk version of this driver already lacks the mmap code