on thinkpad x1v4, the PCMP structure resides in upper reserved memory
pa=0xd7f49000 - while system memory ends at 0x0ffff000; so we have to
vmap() it instead of KADDR().
the RSD structure for ACPI might reside in low memory, so we sould
KADDR() in that case.
on some modern machines like the x250, the bios arranges the mtrr's
and the framebuffer membar in a way that doesnt allow us to mark
the framebuffer pages as write combining, leading to slow graphics.
since the pentium III, the processor interprets the page table bit
combinations of the WT, CD and bit7 bits as an index into the
page attribute table (PAT).
to not change the semantics of the WT and CD bits, we preserve
the bit patterns 0-3 and use the last entry 7 for write combining.
(done in mmuinit() for each core).
the new patwc() function takes virtual address range and changes
the page table marking the range as write combining. no attempt
is made on invalidating tlb's. doesnt matter in our case as the
following mtrr() call in screen.c does it for us.
apparently, this causes some quadcore ramnode vm to hang on boot,
even tho all cores successfully started up and are operational.
i suspect some side effect from timersinit()... this would also
mean *notsc= would break it (syncclock() would continue)...
its unclear.
i'm reverting this for now until the problem is better understood.
when testing in qemu, launching each ap became slower and slower
because all the ap's where spinning in syncclock() waiting for
cpu0 to update its mach0->tscticks, which happens only much later
after all cpu's have been started up.
now we wait for each cpu to do its timer callibration and
manually update our tscticks while we wait and each cpu will
not spin but halt while waiting for active.thunderbirdsarego.
this reduces the system load and noise for timer callibration
and makes the mp startup linear with regard to the number of
cores.
introduce cpushutdown() function that does the common
operation of initiating shutdown, returning once all
cpu's got the message and are about to shutdown. this
avoids duplicated code which isnt really machine specific.
automatic reboot on panic only when *debug= is not set
and the machine is a cpu server or has no display,
otherwise just hang.
the psaux driver is not used in any kernel configuration and theres
no userspace mouse daemon. i8042auxcmds() is wrong as access
to the user buffer can fault and we are holding an ilocks.
little cleanups in devkbd.
on vmware, loading a new kernel sometimes reboots when
wiggling the mouse. disabling keyboard and mouse on
shutdown fixes the issue.
make sure ps2 mouse is disabled on init, will get re-enabled
in i8042auxenable().
keyboard isnt special anymore, we can just use the devreset
entry point in the device to do the keyboard initialization,
so kbdinit()/kbdenable() are not needed anymore.
Wnode gets two new counters: txcount and txerror
and actrate pointer that will be between minrate
and maxrate.
driver should use actrate instead of maxrate for
transmission when it can provide error feedback.
when a driver detects a transmission failed, it calls
wifitxfail() with the original packet. wifitxfail() then
reduces wn->actrate.
every 256th packet, we optimistically increase wn->actrate
before transmitting.
qemu puts multiboot data after the end of the kernel image, so
to be able to KADDR() that memory early, we extend the initial
identity mapping by 16K. right now we just got lucky with
the pc kernel as it rounds the map to 4MB pages.
the following hooks have been added to the ehci Ctlr
structore to handle cache coherency (on arm):
void* (*tdalloc)(ulong,int,ulong);
void* (*dmaalloc)(ulong);
void (*dmafree)(void*);
void (*dmaflush)(int,void*,ulong);
tdalloc() is used to allocate descriptors and the periodic
frame schedule array. on arm, this needs to return uncached
memory. tdalloc()ed memory is never freed.
dmaalloc()/dmafree() is used for io buffers. this can return
cached memory when when hardware maintains cache coherency (pc)
or dmaflush() is provided to flush/invalidate the cache (zynq),
otherwise needs to return uncached memory.
dmaflush() is used to flush/invalidate the cache. the first
argument tells us if we need to flush (non zero) or
invalidate (zero).
uncached.h is gone now. this change makes the handling explicit.
there are no kernels currently that do page coloring,
so the only use of cachectl[] is flushing the icache
(on arm and ppc).
on pc64, cachectl consumes 32 bytes in each page resulting
in over 200 megabytes of overhead for 32gb of ram with 4K
pages.
this change removes cachectl[] and adds txtflush ulong
that is set to ~0 by pio() to instruct putmmu() to flush
the icache.
intrdisable() will always be able to unregister the interrupt
now, so there is no reason to have it return an error value.
all drivers except uart8250 already assumed it to never fail
and theres no need to maintain that complexity.
mpshutdown() used to call acpireset() making it impossible to build
a kernel without archacpi. now, mpshutdown() is a helper function
that only shuts down the application processors that gets used from
mpreset() and acpireset().
the generic machine reset code in exported by devarch's archreset()
function that is called by mpreset() and from acpireset() as a fallback.
so the code duplication that was in mpshutdown() is avoided.
there is no use for "bootdisk" variable parametrization
of /boot/boot and no point for the boot section with its
boot methods in the kernel configuration anymore. so
mkboot and boot$CONF.out are gone.
move the rules for bootfs.paq creation in 9/boot/bootmkfile.
location of bootfs.proto is now in 9/boot/bootfs.proto.
our /boot/boot target is now just "boot".
