Check for RTC presence to avoid hang with QEMU microvm and rtc=off
parameter.

Test bits 0-6 of MC146818's Register D, which must be 0 according to
the specification. This prevents a later hang in rtcget() when no RTC
is present.

branches: 1.41.6;
x86/intr: Work around sleazy clockintr with a secret frame argument.

PR kern/57197

x86/isa/clock.c: Nix trailing whitespace.

No functional change intended.

branches: 1.39.20;
For struct timecounter, use C99 initializers.
Compile tested. No functional changes intended.

Introduce Xen PVH support in GENERIC.
This is compiled in with
options XENPVHVM
x86 changes:
- add Xen section and xen pvh entry points to locore.S. Set vm_guest
to VM_GUEST_XENPVH in this entry point.
Most of the boot procedure (especially page table setup and switch to
paged mode) is shared with native.
- change some x86_delay() to delay_func(), which points to x86_delay() for
native/HVM, and xen_delay() for PVH

Xen changes:
- remove Xen bits from init_x86_64_ksyms() and init386_ksyms()
and move to xen_init_ksyms(), used for both PV and PVH
- set ISA no-legacy-devices property for PVH
- factor out code from Xen's cpu_bootconf() to xen_bootconf()
in xen_machdep.c
- set up a specific pvh_consinit() which starts with printk()
(which uses a simple hypercall that is available early) and switch to
xencons when we can use pmap_kenter_pa().

Merge the bouyer-xenpvh branch, bringing in Xen PV drivers support under HVM
guests in GENERIC.
Xen support can be disabled at runtime with
boot -c
disable hypervisor

branches: 1.36.6;
Add and use __FPTRCAST, requested by uwe@

add void * casts for the clock interrupt handlers.

Added Microsoft Hyper-V support. It ported from OpenBSD and FreeBSD.

graphical console is not work on Gen.2 VM yet. To use the serial console,
enter "consdev com,0x3f8,115200" on efiboot.

branches: 1.33.56; 1.33.64;
Split mc146818-related functions from clock.c into rtc.c.
Call rtc_set_ymdhms() from xen/xen/clock.c:xen_rtc_set() for xen3 dom0
kernels as the Xen3 hypervisor doesn't write the new date/time to the CMOS
by itself.
Now a XEN3_DOM0 kernel properly updates the CMOS time.

Detach sysbeep0 at shutdown.

branches: 1.31.2;
replace bitmask_snprintf(9) with snprintb(3)

branches: 1.30.6; 1.30.8; 1.30.14;
Fix the qemu (?) problem.

Improve x86 tsc handling:

- Ditch the cross-CPU calibration stuff. It didn't work properly, and it's
near impossible to synchronize the CPUs in a running system, because bus
traffic will interfere with any calibration attempt, messing up the
timings.

- Only enable the TSC on CPUs where we are sure it does not drift. If we are
On a known good CPU, give the TSC high timecounter quality, making it the
default.

- When booting CPUs, detect TSC skew and account for it. Most Intel MP
systems have synchronized counters, but that need not be true if the
system has a complicated bus structure. As far as I know, AMD systems
do not have synchronized TSCs and so we need to handle skew.

- While an AP is waiting to be set running, try and make the TSC drift by
entering a reduced power state. If we detect drift, ensure that the TSC
does not get a high timecounter quality. This should not happen and is
only for safety.

- Make cpu_counter() stuff LKM safe.

branches: 1.28.2; 1.28.4; 1.28.6;
Correct comment about struct timecounter field

Cosmetics: use device_t and cfdata_t.

sysbeep has no softc, use CFATTACH_DECL_NEW.

branches: 1.25.2; 1.25.6;
unbreak i8254_get_timecount() in environments where the
clock interrupt is derived from other sources (e.g. lapic)
and the i8254 timer is running the full cycle without
being used as clock interrupt source.

Remove unnecessary references to config_time.h.

fix clock accounting problem in i8254_get_timecount that caused
the auich auich_calibrate() function to get the wrong ac97 freq
(may cause audio to play at wrong speed on some systems). this
error was inadvertently introduced in rev 1.98 of the old
src/sys/arch/i386/isa/clock.c (2006/09/03) and manifests itself
on systems that do not use an alternate timecounter (e.g. ACPI-Fast).

the basic problem is that the code that handled when the i8254
counter wrapped was firing in cases when it shouldn't have,
causing the counter to run fast. a more detailed discussion
can be found here:
http://mail-index.netbsd.org/tech-kern/2008/01/15/0001.html
http://mail-index.netbsd.org/tech-kern/2008/01/16/0000.html

Remove superfluous #if (NPCPPI > 0).

Move #endif to the place where it belongs. Thanks, Chavdar Ivanov,
for noticing this.

Start detangling lock.h from intr.h. This is likely to cause short term
breakage, but the mess of dependencies has been regularly breaking the
build recently anyhow.

add missing includes

Declare sysbeepdetach(), and protect a small additional section
with #if (NPCPPI > 0).

Support detachment of pchb(4) and sysbeep(4).

Remove delaytab and just compute the reminder directly. This requires
two muls and a shift, which needs at most 2ms on a 25MHz i386 and should
end up as fast as delay(1) was before due to using a reminder of 2.
Discussed with ad@.

branches: 1.15.2;
Merge jmcneill-pm branch.

branches: 1.14.2;
- Fix the locking around the i8254. Values for the TSC clock and lapic
delay function were wildly inaccurate due to multiple CPUs competing
in DELAY() during calibration, confusing the clock chip.
- Use i8254_delay() explictly in a few more places.

branches: 1.13.2;
- Remove I486_CPU, I586_CPU, I686_CPU options. They buy us nothing and
clutter the code significantly.
- Remove pccons.

branches: 1.12.2;
Match delay/DELAY on x86 with delay(9). It takes an unsigned int as
argument. Use this and replace the inline assembly (mul + div using the
64bit intermediate result) with normal 32bit multiplication and
division. The compiler can turn the division into a multiplication and
shift, making it even cheaper then the original assembly. For extreme
long delays, just use 64bit arithmetic.

Merge the ppcoea-renovation branch to HEAD.

This branch was a major cleanup and rototill of many of the various OEA
cpu based PPC ports that focused on sharing as much code as possible
between the various ports to eliminate near-identical copies of files in
every tree. Additionally there is a new PIC system that unifies the
interface to interrupt code for all different OEA ppc arches. The work
for this branch was done by a variety of people, too long to list here.

TODO:
bebox still needs work to complete the transition to -renovation.
ofppc still needs a bunch of work, which I will be looking at.
ev64260 still needs to be renovated
amigappc was not attempted.

NOTES:
pmppc was removed as an arch, and moved to a evbppc target.

branches: 1.10.2;
x86 changes for pcc and LKMs.

- Replace most inline assembly with proper functions. As a side effect
this reduces the size of amd64 GENERIC by about 120kB, and i386 by a
smaller amount. Nearly all of the inlines did something slow, or something
that does not need to be fast.
- Make curcpu() and curlwp functions proper, unless __GNUC__ && _KERNEL.
In that case make them inlines. Makes curlwp LKM and preemption safe.
- Make bus_space and bus_dma more LKM friendly.
- Share a few more files between the ports.
- Other minor changes.

branches: 1.9.8; 1.9.10; 1.9.12;
Merge some of the less invasive changes from the vmlocking branch:

- kthread, callout, devsw API changes
- select()/poll() improvements
- miscellaneous MT safety improvements

branches: 1.8.2; 1.8.8; 1.8.10; 1.8.16;
- pass intrframe by-pointer, not by-value.
- make i386 and xen use per-cpu interrupt stack.

xen part is reviewed by Manuel Bouyer.

branches: 1.7.2; 1.7.4;
__unused removal on arguments; approved by core.

More __unused (NPCPPI == 0 case).

- sprinkle __unused on function decls.
- fix a couple of unused bugs
- no more -Wno-unused for i386

branches: 1.4.2; 1.4.4; 1.4.6; 1.4.8;
Use common todr_settime_ymdhms/gettime_ymdhms.
While here, fix an incorrect test for timeset (that's in kern_todr already),
and an incorrect to time_second (instead of using the date passed in).

Remove unused todr_setcal/todr_getcal and all the assorted stub
implementations.

Undo static declaration on gettick -- lapic.c uses it.
Pointed out by Geoff Wing (mason at primenet.com.au)

switch to a common clock.c

Use device_{get,set}prop_bool() for "no-legacy-devices".

Disable FADT LEGACY_DEVICES flag test.

This test had the unintended side-effect of blocking the lm(4) driver
from attaching on more than one system. Go back to (slow) probing of
ISA devices for now to restore existing functionality.

Correct copypaste comment grammar.

Trailing whitespace

Skip legacy device detection for VMware guests with ACPI enabled.

Add missing acpi include

If ACPI indicates that there are no user visible devices on the LPC or ISA
bus, set the "no-legacy-devices" property on isa to bypass indirect
configuration of ISA devices.

Introduce Xen PVH support in GENERIC.
This is compiled in with
options XENPVHVM
x86 changes:
- add Xen section and xen pvh entry points to locore.S. Set vm_guest
to VM_GUEST_XENPVH in this entry point.
Most of the boot procedure (especially page table setup and switch to
paged mode) is shared with native.
- change some x86_delay() to delay_func(), which points to x86_delay() for
native/HVM, and xen_delay() for PVH

Xen changes:
- remove Xen bits from init_x86_64_ksyms() and init386_ksyms()
and move to xen_init_ksyms(), used for both PV and PVH
- set ISA no-legacy-devices property for PVH
- factor out code from Xen's cpu_bootconf() to xen_bootconf()
in xen_machdep.c
- set up a specific pvh_consinit() which starts with printk()
(which uses a simple hypercall that is available early) and switch to
xencons when we can use pmap_kenter_pa().

Merge the bouyer-xenpvh branch, bringing in Xen PV drivers support under HVM
guests in GENERIC.
Xen support can be disabled at runtime with
boot -c
disable hypervisor

branches: 1.44.10;
We reorganise definitions for XEN source support as follows:

XEN - common sources required for baseline XEN support.
XENPV - sources required for support of XEN in PV mode.
XENPVHVM - sources required for support for XEN in HVM mode.
XENPVH - sources required for support for XEN in PVH mode.

Excise XEN specific code out of x86/x86/intr.c into xen/x86/xen_intr.c

While at it, separate the source function tracking so that the interrupt
paths are truly independant.

Use weak symbol exporting to provision for future PVHVM co-existence
of both files, but with independant paths. Introduce assembler code
such that in a unified scenario, native interrupts get first priority
in spllower(), followed by XEN event callbacks. IPL management and
semantics are unchanged - native handlers and xen callbacks are
expected to maintain their ipl related semantics.

In summary, after this commit, native and XEN now have completely
unrelated interrupt handling mechanisms, including
intr_establish_xname() and assembler stubs and intr handler
management.

Happy Christmas!

Remove unused mbuf.h includes.

Allow isa_machdep.c to compile in the case of no ioapic support.

Remove the last usage of xen_pirq_alloc() and pirq_establish()
outside of the x86 interrupt and xen events framework.

This allows us to finally unify the interrupt path for both Xen
and x86 as changes 'internal' to the subsystem.

This change has been kindly tested on real hardware by gson@

The change is not cosmetic and may thus affect users on various
hardware configurations - especially involving legacy hardware.

I look forward to bug reports.

branches: 1.39.2;
add support for kern.intr.list aka intrctl(8) 'list' for xen

event_set_handler() and pirq_establish() now have extra intrname
parameter; shared intr_create_intrid() is used to provide the value

xen drivers were changed to pass the specific driver instance
name as the xname, e.g. 'vcpu0 clock' instead just 'clock', or
'xencons0' instead of 'xencons'

associated evcnt is now changed to use intrname - this matches native x86

branches: 1.38.2;
Fixes for physical interrupts on Xen:
- do not cast int * to intr_handle_t *, they're not the same size
- legacy_irq is not always -1 for ioapic interrupts, test pic_type instead
- change irq2port[] to hold (port + 1) so that 0 is an invalid value
- add KASSERTs to make sure vect, port or irq values extracted from arrays are
valid (or that they are invalid before write)
- for the !ioapic case, we still need to do PHYSDEVOP_ASSIGN_VECTOR and
bind_pirq_to_evtch().

now XEN3_DOM0 boots again

Retire xen/x86/intr.c and use the new xen specific glue in x86/x86/intr.c

The purpose of this change is to expose the x86/include/intr.h API
to drivers. Specifically the following functions:

void *intr_establish_xname(...);
void *intr_establish(...);
void intr_disestablish(...);

while maintaining the old API from xen/include/evtchn.h, specifically
the following functions:

int event_set_handler(...);
int event_remove_handler(...);

This is so that if things break, we can keep using the old API until
everything stabilises. This is a stepping stone towards getting the
actual XEN event callback path rework code in place - which can be
done opaquely behind the intr.h API - NetBSD/XEN specific drivers that
have been ported to the intr.h API should then work without
significant further modifications.

Fix uninitialised use of variable mpih

Pointed out by joerg@

branches: 1.35.2;
Remove the xen specific interrupt type for the x86 intr_handle_t
For this to work, we use the evtchn.c:get_pirq_to_evtchn() glue
function to make things easier.

provide intr xname

branches: 1.33.2;
add intr_handle_t and let pci_intr_handle_t use it.

branches: 1.32.2; 1.32.16;
cosmetic, spelling, and grammar adjustments

branches: 1.31.2; 1.31.6;
Factor device_isa_register() and device_pci_register() out of
device_register() and stick the new routines into isa_machdep.c and
pci_machdep.c, respectively.

Add bus_dma overrides. From dyoung

use c99 struct initializers

isa_detach_hook() needs two arguments, the first an isa_chipset_tag_t.

These are stragglers from my last commit ("Let us safely detach
the ISA bus and devices attaching to the ISA bus"). Define
isa_detach_hook() in MD ISA implementations. Define isa_dmadestroy().

cpuctl:

- Add interrupt shielding (direct hardware interrupts away from the
specified CPUs). Not documented just yet but will be soon.

- Redo /dev/cpu time_t compat so no kernel changes are needed.

x86:

- Make intr_establish, intr_disestablish safe to use when !cold.

- Distribute hardware interrupts among the CPUs, instead of directing
everything to the boot CPU.

- Add MD code for interrupt sheilding. This works in most cases but there is
a bug where delivery is not accepted by an LAPIC after redistribution. It
also needs re-balancing to make things fair after interrupts are turned
back on for a CPU.

Remove all the __P() from sys (excluding sys/dist)
Diff checked with grep and MK1 eyeball.
i386 and amd64 GENERIC and sys still build.

branches: 1.24.2;
remove unused malloc.h

branches: 1.23.4;
Remove "struct device" from "struct pic", where it was only real
for ioapics and faked up for others. Add it to "struct ioapic_softc"
for now, until device/softc get split.
This required all typecasts between "struct pic" and "struct ioapic_softc"
to be replaced, I hope I got them all.
functionally tested on i386, compile-tested on xen, untested on amd64

struct device * -> device_t

ansify

branches: 1.20.2;
Add a 'known_mpsafe' argument to intr_establish().

branches: 1.19.2;
Remove clause 3 and 4 from TNF licenses

branches: 1.18.16; 1.18.18; 1.18.20;
Merge the ppcoea-renovation branch to HEAD.

This branch was a major cleanup and rototill of many of the various OEA
cpu based PPC ports that focused on sharing as much code as possible
between the various ports to eliminate near-identical copies of files in
every tree. Additionally there is a new PIC system that unifies the
interface to interrupt code for all different OEA ppc arches. The work
for this branch was done by a variety of people, too long to list here.

TODO:
bebox still needs work to complete the transition to -renovation.
ofppc still needs a bunch of work, which I will be looking at.
ev64260 still needs to be renovated
amigappc was not attempted.

NOTES:
pmppc was removed as an arch, and moved to a evbppc target.

branches: 1.17.10;
Merge some of the less invasive changes from the vmlocking branch:

- kthread, callout, devsw API changes
- select()/poll() improvements
- miscellaneous MT safety improvements

branches: 1.16.4; 1.16.6; 1.16.12;
add a pair of new bus_dma(9) functions:
int _bus_dmatag_subregion(bus_dma_tag_t tag,
bus_addr_t min_addr,
bus_addr_t max_addr,
bus_dma_tag_t *newtag,
int flags)
void _bus_dmatag_destroy(bus_dma_tag_t tag)

that allow a (normally broken/limited) device to restrict the bus address
range it can talk to. this is used by bce(4) to limit DMA addresses to
1GB range, the maximum the chip can address.

all this is from Yorick Hardy <yhardy@uj.ac.za> with input from several
people on tech-kern.

XXX: bus_dma(9) needs an update still.

branches: 1.15.4;
__unused removal on arguments; approved by core.

- sprinkle __unused on function decls.
- fix a couple of unused bugs
- no more -Wno-unused for i386

branches: 1.13.20; 1.13.22;
merge ktrace-lwp.

branches: 1.12.2;
tweak x86 bus_dma code so that it can be used by xen port.

- distinguish paddr_t and bus_addr_t.
for xen, use bus_addr_t in the sense of machine address.
- move _X86_BUS_DMA_PRIVATE part of bus.h into bus_private.h.
- remove special handling of xen_shm. we can always grab
machine address from pte.

branches: 1.11.4; 1.11.10;
Remove the "ID" component of the x86 bus_dma flags, since these are no
longer "ISA DMA" specific flags.

* keep track of PCI buses that aren't known by firmware, but are found
by NetBSD
* use this info in in intr_find_mpmapping
* get rid of the last argument to intr_find_mpmapping, it was redundant

Add hooks and structures to allow the MP table intr mapping code a
better shot at finding a mapping. For PCI interrupts, if a bus
has no mappings, try its parent, with the swizzled pin, and the
bridge's device number.

Move UCB-licensed code from 4-clause to 3-clause licence.

Patches provided by Joel Baker in PR 22364, verified by myself.

branches: 1.7.2;
Generalize bounce buffers, and use them for 32 bit PCI if needed.
Make ALLOCNOW the default iff bouncing might be needed (this has
no effect on i386 because ISA DMA devices already had to use
ALLOCNOW, and PCI isn't bounced (yet), since we don't do > 4G
at this point for i386.

Move definition of ISA_DMA_BOUNCE_THRESHOLD to dev/isa/isareg.h.

DMA, not dma nor Dma.

s/i386_isa_chipset/x86_isa_chipset/

Clean up some unneeded "mca.h" and "eisa.h" includes, make one that is
needed dependent on !__x86_64__. To be revisited later.

x86_64 has no mca.h and eisa.h (should perhaps just generate empty ones)

Moved here from i386/isa

Remove unnecessary NULL-initialization of TODR handle fields.

Only use FADT Century byte if it targets a valid 146818 NVRAM location.

Should fix PR 57821.

branches: 1.2.6;
Honor ACPI FADT Century byte; should fix many "unknown CMOS layout" messages.

branches: 1.1.2; 1.1.4; 1.1.6; 1.1.12; 1.1.102;
Split mc146818-related functions from clock.c into rtc.c.
Call rtc_set_ymdhms() from xen/xen/clock.c:xen_rtc_set() for xen3 dom0
kernels as the Xen3 hypervisor doesn't write the new date/time to the CMOS
by itself.
Now a XEN3_DOM0 kernel properly updates the CMOS time.