When the HPET enters legacy mode, the IRQ output of the PIT is
suppressed and replaced by the HPET timer 0. But the current code to
emulate this was broken in many ways. It reset the PIT state after
re-enabling, it worked against a stale static PIT structure, and it did
not properly saved/restored the IRQ output mask in the PIT vmstate.
This patch solves the PIT IRQ control in a different way. On x86, it
both redirects the PIT IRQ to the HPET, just like the RTC. But it also
keeps the control line from the HPET to the PIT. This allows to disable
the PIT QEMU timer when it is not needed. The PIT's view on the control
line state is now saved in the same format that qemu-kvm is already
using.
Note that, in contrast to the suppressed RTC IRQ line, we do not need to
save/restore the PIT line state in the HPET. As we trigger a PIT IRQ
update via the control line, the line state is reconstructed on mode
switch.
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Most changes were made using these commands:
git grep -la '__attribute__((packed))'|xargs perl -pi -e 's/__attribute__\(\(packed\)\)/QEMU_PACKED/'
git grep -la '__attribute__ ((packed))'|xargs perl -pi -e 's/__attribute__ \(\(packed\)\)/QEMU_PACKED/'
git grep -la '__attribute__((__packed__))'|xargs perl -pi -e 's/__attribute__\(\(__packed__\)\)/QEMU_PACKED/'
git grep -la '__attribute__ ((__packed__))'|xargs perl -pi -e 's/__attribute__ \(\(__packed__\)\)/QEMU_PACKED/'
git grep -la '__attribute((packed))'|xargs perl -pi -e 's/__attribute\(\(packed\)\)/QEMU_PACKED/'
Whitespace in linux-user/syscall_defs.h was fixed manually
to avoid warnings from scripts/checkpatch.pl.
Manual changes were also applied to hw/pc.c.
I did not fix indentation with tabs in block/vvfat.c.
The patch will show 4 errors with scripts/checkpatch.pl.
Signed-off-by: Stefan Weil <weil@mail.berlios.de>
Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
Currently HPET ACPI table is created regardless of whether qemu actually
created hpet device. This may confuse some guests that don't check that
hpet is functional before using it. Solve this by passing info about
hpets in qemu to seabios via fw config interface. Additional benefit is
that seabios no longer uses hard coded hpet configuration. Proposed
interface supports up to 8 hpets. This is the number defined by hpet
spec.
Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
This implements the HPET capability of routing IRQs to the front-side
bus, aka MSI support. This feature can be enabled via the qdev property
"msi" and is off by default.
Note that switching it on can cause guests (at least Linux) to use the
HPET as timer instead of the LAPIC. KVM users should recall that only
the latter is currently available as fast in-kernel model.
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
One HPET block supports up to 32 timers. Allow to instantiate more than
the recommended and implemented minimum of 3. The number is configured
via the qdev property "timers". It is also saved/restored so that it
need not match between migration peers.
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
Allow the intercept the RTC IRQ for the HPET legacy mode. Then push
routing to IRQ8 completely into the HPET. This allows to turn
hpet_in_legacy_mode() into a private function. Furthermore, this stops
the RTC from clearing IRQ8 even if the HPET is in control.
This patch comes with a side effect: The RTC timers will no longer be
stoppend when there is no IRQ consumer, possibly causing a minor
performance degration. But as the guest may want to redirect the RTC to
the SCI in that mode, it should normally disable unused IRQ source
anyway.
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
Register the HPET as a sysbus device and create it that way. As it can
route its IRQs to any ISA IRQ, we need to connect it to all 24 of them.
Once converted to qdev, we can move reset handler and vmstate
registration into its hands as well.
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
This moves the private HPET structures into the C module, simplifies
some helper functions and fixes most coding style issues (biggest chunk
was improper switch-case indention). No functional changes.
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
This patch addresses the problems found by Andriy Gapon:
- The code was incorrectly overwriting the high order 32
bits of the timer and hpet config registers. This didn't show up
in testing because linux and windows use hpet in legacy mode,
where the high order 32 bits (advertising available interrupts)
of the timer config register are ignored, and the high order 32
bits of the hpet config register are reserved and unused.
- The mask for level-triggered interrupts was off by a bit. (hpet
doesn't currently support level-triggered interrupts).
In addition, I removed some unused #defines, and corrected the ioapic
interrupt values advertised. I'd set this up early in hpet development
and never went back to correct it, and no bugs resulted since linux and
windows use hpet in legacy mode where available interrupts are ignored.
Signed-off-by: Beth Kon <eak@us.ibm.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
I discovered a bug in the hpet code that caused Windows to boot without
hpet. The config mask I was using was preventing the guest from placing
the hpet into 32 bit mode.
(Beth Kon)
git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@6357 c046a42c-6fe2-441c-8c8c-71466251a162
This patch adds HPET emulation. It can be disabled with -disable-hpet. An hpet
provides a more finely granular clocksource than otherwise available on PC.
This means that latency-dependent applications (e.g. multimedia) will generally
be smoother when using the HPET.
Signed-off-by: Beth Kon <eak@us.ibm.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@6081 c046a42c-6fe2-441c-8c8c-71466251a162
