[U-Boot-Users] Regarding Dcache Flush in MPC85xx

[Kumar Gala]

On Feb 26, 2008, at 11:30 AM, s.balamurugan wrote:

> Hi,
> We are using MPC8555 processor and uboot 1.1.4 both the uboot and  
> linux
> was up. Now we plan to port QNX, we are facing following issues.
>
> 1. Qnx is not jumping to the startup location.  After giving go  
> command
> control is still in the uboot only.
>
> 2.  When searching in the mailling list we came to know qnx required  
> to
> flush the Data Cache before disabling it in the uboot level
> (common/cmd_bootelf.c line no:59)
>
> 3.  I checked other powerpc architecture like 7xx/74xx, 86xx and 4xx.
> These architecture  has seperate cache.S file ( cpu/mpc86xx/ 
> cache.S). That
> file contains flush_data_cache function to flush the cache before
> disabling it. But in the MPC85xx flushing the data cache was missing.
>
> 4. This is a bug in the 85xx uboot code. Is there any work arround for
> this?

1.1.4 is a fairly old u-boot at this point.  I believe we have  
reworked the PPC cache ops and fixed the fact that 85xx was missing  
flush_data_cache in the process.

- k