According to the PPC reference implementation the udelay() function is
responsible for resetting the watchdog timer as frequently as needed.
Most other architectures do not meet that requirement, so long-running
operations might result in a watchdog reset.
This patch adds a generic udelay() function which takes care of
resetting the watchdog before calling an architecture-specific
__udelay().
Signed-off-by: Ingo van Lil <inguin@gmx.de>
- According to ARM Dual-Timer Module (SP804) TRM (ARM DDI0271),
-- Timer Value Register @ TIMER Base + 4 is Read-only.
-- Prescale Value (Bits 3-2 of TIMER Control register)
can only be one of 00,01,10. 11 is undefined.
-- CFG_HZ for Versatile board is set to
#define CFG_HZ (1000000 / 256)
So Prescale bits is set to indicate
- 8 Stages of Prescale, Clock divided by 256
- The Timer Control Register has one Undefined/Shouldn't Use Bit
So we should do read/modify/write Operation
Signed-off-by: Gururaja Hebbar <gururajakr@sanyo.co.in>
Modifications are based on the linux kernel approach and
support two use cases:
1) Add O= to the make command line
'make O=/tmp/build all'
2) Set environement variable BUILD_DIR to point to the desired location
'export BUILD_DIR=/tmp/build'
'make'
The second approach can also be used with a MAKEALL script
'export BUILD_DIR=/tmp/build'
'./MAKEALL'
Command line 'O=' setting overrides BUILD_DIR environent variable.
When none of the above methods is used the local build is performed and
the object files are placed in the source directory.
