u-boot-brain/arch
Marek Vasut 8f975865be i.MX28: Add delay after CPU bypass is cleared
This solves issues when larger amount of DRAM is used, like 256MB.
Behave the same in case of CPU bypass as we do in case of EMI
bypass, but wait 15 ms. We need to wait until the clock domain
stabilizes.

This issue seemed to have been caused by not waiting after frobbing
with the CPU bypass, it was unrelated to memory, but had a direct
impact, causing trouble. This was yet another X-File of the
imx-bootlets, sigh. The conclusion is, trying a semi-random delay
(there is delay after the EMI bypass change), the issue is fixed.

Another possible explanation is that we do not do the "simple memory
test" FSL does in their imx-bootlets (1000 R/W cycles to/from piece of
the memory, while also outputing something on the serial port). This
might have caused the similar delay in the imx-bootlets and therefore
they didn't need to add this explicitly.

For now, this seems good fix enough, but to me, whole that memory
init code in imx-bootlets is completely flunked and it'd need deeper
investigation.

Signed-off-by: Marek Vasut <marex@denx.de>
Cc: Wolfgang Denk <wd@denx.de>
Cc: Detlev Zundel <dzu@denx.de>
Cc: Stefano Babic <sbabic@denx.de>
Cc: Fabio Estevam <festevam@gmail.com>
Acked-by: Stefano Babic <sbabic@denx.de>
Acked-by: Detlev Zundel <dzu@denx.de>
2012-05-15 08:31:35 +02:00
..
arm i.MX28: Add delay after CPU bypass is cleared 2012-05-15 08:31:35 +02:00
avr32 bootstage: Replace show_boot_progress/error() with bootstage_...() 2012-03-18 21:41:39 +01:00
blackfin Blackfin: move gd/bd to bss by default 2012-04-22 13:00:19 -04:00
m68k bootstage: Replace show_boot_progress/error() with bootstage_...() 2012-03-18 21:41:39 +01:00
microblaze bootstage: Replace show_boot_progress/error() with bootstage_...() 2012-03-18 21:41:39 +01:00
mips MIPS: fix endianess handling 2012-04-02 15:54:53 +02:00
nds32 nds32/ag102: add ag102 soc support 2012-04-22 16:58:23 +08:00
nios2 nios2: implement get_ticks and get_tbclk 2012-02-23 08:31:20 +08:00
openrisc openrisc: Add library functions 2012-01-13 21:16:48 +01:00
powerpc powerpc/85xx: don't touch MAS7 on e500v1 when relocating CCSR 2012-04-24 23:58:34 -05:00
sandbox sandbox: Use the new run_command() 2012-04-23 22:53:54 +02:00
sh Prepare v2012.04-rc2; minor Coding Style cleanup 2012-04-16 23:13:51 +02:00
sparc usb: replace wait_ms() with mdelay() 2012-03-19 00:08:16 +01:00
x86 sc520: fix build warning about unused temp var 2012-03-06 21:05:18 +11:00
.gitignore update include/asm/ gitignore after move 2010-05-07 00:17:30 +02:00