there is one. The Mach VM system seems to take care of this, so it
hasn't knowingly caused a problem. UVM does change mappings without
removing the current mapping, and will pmap_page_protect() hangs
if pmap_enter() doesn't remove the previous mapping.
prototype declearation for method to override wbflush() callback
vector with model-specific code. Used on DEC r2000a machines with
writebuffers which indicate writebuffer drain via cp0 usability bit.
read and write compare register (controls cycle-driven periodic interrupt).
Use cycle counter for microsecond time on mips3, but for now only on
3min motherboards (5000/150). the MAXINE baseboard microsecond
counter is more stable and I don't ave no 5000/260 to test.
XXX clkread() is a mess, it should be rewritten.
XXX should add nanotime() to give inkernel nanosecond resolution,
and then microtime() reworked to use nanotime().
interrupt-callout vector from mips locore dispatch code to port code.
* Move branch-emulation declaration to mips/include/trap.h.
* Garbage-collect pmax/pmax/trap.h.
Not needed now pmax/pmax_trap.c is gone, and after above tidy-up.
common place:
- allocsys(), which computes space for and assigns addresses
to kernel data structures at boot time.
- mips_init_msgbuf(), which initializes the error message
buffer at the end of core.
- mips_init_proc0(), which initializes the U-area for proc0
and nullproc.
didn't make it in. Aproved by Jonathan and tested here at Stanford.
While I'm here, add conditional prototypes for clnlintr() and nsintr()
so that NS and ISO will compile correctly.
to the TLB dump routines arguements. Machines would die horibbly when
trying to dump the TLB entries in DDB. Also don't explicitly "page" the
output, since db_printf takes care of that.
if the break instruction is still there. This works around a problem with
the software single step in DDB not recognizing the temporary breakpoint
set to emulate the single step.
- fix _C_LABEL so that it actually works.
- make __RENAME use _C_LABEL.
- fix __RENAME so that it expects an unquoted argument.
- fix __indr_reference and __warn_references so that they
supply their own final semicolon.
- define __warn_references to nothing if not GNU C (required
by the way it's used).
The __warn_references semicolon change has to be made
so that __warn_references can be defined into nothing.
(A ; all by itself isn't a great idea.) The __indr_reference
change was made for consistency.
From /sys/news3400/news3400/locore.s, with id
@(#)locore.s 8.3 (Berkeley) 9/23/93
Kazumasa Utashiro notes that the pmax cacheflush routines don't work:
#ifndef NOTDEF /* I don't know why Ralph's code doesn't work. KU:XXX */
It's because pmax hardware wries the COP0 bit to external branch
logic. news3400s don't, and so the bc0f loop fails. It will also
fail on some other models of pmax, but we dont' support them.
Surround the relevant framgents in locore_r200.S with "#ifdef pmax".
Longer-term, the cacheflush entry in the locore callback may have
to be a CPU baseboard-specific entry, not just CPU-version specific.
(_BYTE_ORDER, _BIG_ENDIAN, _LITTLE_ENDIAN).
Define old names from the ANSI ones if not _POSIX_SOURCE.
* Define _QUAD_HIGHWORD and _QUAD_LOWWORD properly when
_BYTE_ORDER == _BIG_ENDIAN.
Only assembly version for i386 bswap16 and bswap32 for now (bswap64 uses
bswap32). Contribution of assembly versions of these are welcome.
Add byte-swapping of ext2fs metadata for big-endian systems.
Tested on i386 and sparc.
msgbuf. Note that old 'dmesg' and 'syslogd' binaries will continue running,
though old 'dmesg' binaries will output a few bytes of junk at the start of
the buffer, and will miss a few bytes at the end of the buffer.
Compute CPU speed(MHz) and loop multiplier for DELAY() based on
counting empty loop between mcclock ticks. New global: cpu_mhz.
Change pmax/pmax/machdep.c to build baseboard model names from cpu_mhz.
Set 'cpuspeed' for more realistic DELAY() on mips3 models.
Mips CPU constants, testing, and calibration from D. Sean Davidson
<davidson@zk3.dec.com> and Simon Burge <simonb@telstra.com.au>.
* prototype and definition for pmap_activate(p). Updates the segtab,
and changes the active ASID if p == curproc.
* Make reserved fixed-address (UADDR) kernelstack PTEs global,
so we still have a kernel stack after pmap_activate() on curproc.
* make KSEG2 mappings for p_addr global (see above.)
Seems to detune contextswitch and NTP resolution (by 60 ms), but
thepmap_activate() interface is mandatory. Needs more thought.
of cache-index incompatible virtual mappings for a physical page may be
required for hardware without secondary (level 2) cache to detect and
correct virtual coherency problems. I'm not sure this is really needed
anymore, since pmap_prefer() took care of of the cache-index
incompatible mappings that I have seen. Count the times a page is
cache inhibited in enter_stats if DEBUG.
Wait for memory instead of panic() on failure to allocate a page for the
segtab or segmap [from OpenBSD arc port]. Also check for malloc()
failure on allocation of a new pv entry and panic().
Increment resident_count when adding a new page to a pmap [also from
OpenBSD]. Process resident size is now valid.
cache flush operations required on a virtually-indexed, physically-tagged
mips3 with no L2 cache to provide cache-coherence exceptions.
(Similar to what's needed with a virtually-indexed, virtually-tagged cache.)
faults. Use curpcb, which always points to the current pcb. If curproc
was NULL when the kernel faulted, the trap handling would fault recursively
and the kernel stack would overflow.
Has unrolled loop for aligned-to-aligned copy.
Notes:
1. this code tuned for DEC 5000/200. ioasic decstations do more unaligned
copies. Better than old non-unrolled loop, but could be improved.
2. Undoes changes made for MIPS3 with comment implying an r4000 TLB bug.
We can't reproduce this on 5000/150 (jonathan) or 5000/50 (mhitch).
Calls to previous bcopy with a bad address show similar symptoms,
reporting a trap in bcopy() after bcopy() has returned. Same thing??
Needs re-checking on an r4000 with no L2 cache.
sigcode():
executed from user-space stack.
mips1_cpu_switch_resume, mips3_cpu_switch_resume:
arguments passed in via v0, t0, t1 (outlined from cpu_switch())
mips3_VCED(), mips3_VCEI():
called from exception-vector code without any register save,
$at, $ra are live.
kleink