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>
MIPS port has two problems in timer routines. One is now we assume CFG_HZ
equals to CP0 counter frequency, but this is wrong. CFG_HZ has to be 1000
in the U-Boot system.
The other is we don't have a proper time management counter like timestamp
other ARCHs have. We need the 32-bit millisecond clock counter.
This patch introduces timestamp and CYCLES_PER_JIFFY. timestamp is a
32-bit non-overflowing CFG_HZ counter, and CYCLES_PER_JIFFY is the number
of calculated CP0 counter cycles in a CFG_HZ.
STRATEGY:
* Fix improper CFG_HZ value to have 1000
* Use CFG_MIPS_TIMER_FREQ for timer counter frequency, instead.
* timer_init: initialize timestamp and set up the first timer expiration.
Note that we don't need to initialize CP0 count/compare registers here
as they have been already zeroed out on the system reset. Leave them as
they are.
* get_timer: calculate how many timestamps have been passed, then return
base-relative timestamp. Make sure we can easily count missed timestamps
regardless of CP0 count/compare value.
* get_ticks: return the current timestamp, that is get_timer(0).
Most parts are from good old Linux v2.6.16 kernel.
v2:
- Remove FIXME comments as they turned out to be trivial.
- Use CP0 compare register as a global variable for expirelo.
- Kill a global variable 'cycles_per_jiffy'. Use #define CYCLES_PER_JIFFY
instead.
Signed-off-by: Shinya Kuribayashi <skuribay@ruby.dti.ne.jp>
What we have to do is just to wait for given micro-seconds. No need to
take into account current time, get_timer and CFG_HZ.
Signed-off-by: Shinya Kuribayashi <skuribay@ruby.dti.ne.jp>
We already have many pre-defined CP0 access macros in <asm/mipsregs.h>.
This patch replaces mips_{compare,count}_set and mips_count_get with
existing macros.
Signed-off-by: Shinya Kuribayashi <skuribay@ruby.dti.ne.jp>
allow selection of clock frequency as "make" target
* Implement memory autosizing code for IceCube boards
* Configure network port on INCA-IP for autonegotiation
* Fix overflow problem in network timeout code
* Patch by Richard Woodruff, 8 Aug 2003:
Allow crc32 to be used at address 0x000 (crc32_no_comp, too).
- remove trailing white space, trailing empty lines, C++ comments, etc.
- split cmd_boot.c (separate cmd_bdinfo.c and cmd_load.c)
* Patches by Kenneth Johansson, 25 Jun 2003:
- major rework of command structure
(work done mostly by Michal Cendrowski and Joakim Kristiansen)
