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   

 

Hi,

 

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.

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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...

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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);

#define HAVE_ARCH_FB_UNMAPPED_AREA

 

-Michael

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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.

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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

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