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

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