| Age | Commit message (Collapse) | Author | Files | Lines |
|---|
|
There's a fallback to PIT if TSC is not present but it doesn't work
properly. It prevents boot from floppy on isapc and 486 cpu [1][2].
SeaBIOS configures PIT in Mode 2. PIT counter is decremented in the mode
but timer_adjust_bits() thinks that the counter overflows and increases
32-bit tick counter on each detected "overflow". Invalid overflow
detection results in 55ms time advance (1 / 18.2Hz) on each read from
PIT counter. So all timers expire much faster and 5-second floppy
timeout expires in 83 real microseconds (or just a bit longer).
It can be fixed by making the counter recieved from PIT an increasing
value so it can be passed to timer_adjust_bits():
0, 1, 2 and up to 65535 and then the counter is re-loaded with 0.
1. https://bugs.launchpad.net/seabios/+bug/1840719
2. https://lists.gnu.org/archive/html/qemu-devel/2019-08/msg03924.html
Fixes: eac11944019 ("Unify pmtimer_read() and pittimer_read() code.")
Reported-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Signed-off-by: Roman Bolshakov <r.bolshakov@yadro.com>
|
|
Add function to set tsc frequency directly, without calibration.
Also tweak timer setup functions a bit: skip setup in case TimerPort
has not the default value any more, i.e. another timer has been setup
already.
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Message-id: 20200310102248.28412-1-kraxel@redhat.com
|
|
When timer_calc_usec() is used with large timeout values, such as 60s,
the integer math can overflow and produce different results than when
using timer_calc(time / 1000) for the same timeout.
Signed-off-by: Stefan Berger <stefanb@linux.vnet.ibm.com>
Signed-off-by: Kevin O'Connor <kevin@koconnor.net>
|
|
Some Chromebooks (with Baytrail CPUs) apparently do not support
routing of legacy interrupts. This patch adds minimal support for
running SeaBIOS in such an environment. Even with this patch, it is
known that old operating systems and even some recent bootloaders will
not function without real hardware interrupts.
Signed-off-by: Kevin O'Connor <kevin@koconnor.net>
|
|
Allow users to remove the CPU timestamp counter support at compile
time. The PMTIMER is frequently used instead of the TSC and this
compile time option allows one to strip a few bytes from the final
binary. This change also defaults the internal timer to use the PIT
based timer until the PMTIMER or TSC is detected.
Signed-off-by: Kevin O'Connor <kevin@koconnor.net>
|
|
The PORT_PS2_CTRLB port is only used by timers - it's just a
historical artifact that it was part of the original ps2 controller.
Signed-off-by: Kevin O'Connor <kevin@koconnor.net>
|
|
Move the inb(), insb(), etc. code from ioport.h to x86.h. Move the
PORT_* definitions to their appropriate hardware files.
Signed-off-by: Kevin O'Connor <kevin@koconnor.net>
|
|
Move the hardware setup to the hw/timer.c code. This eliminates the
need for a separate hw/pit.h file with definitions.
Also, move the IRQ counting code (which is dependent on the BDA) from
hw/timer.c to clock.c.
Signed-off-by: Kevin O'Connor <kevin@koconnor.net>
|
|
Also, sort the order of include files in the c files.
Signed-off-by: Kevin O'Connor <kevin@koconnor.net>
|
|
Signed-off-by: Kevin O'Connor <kevin@koconnor.net>
|
|
Signed-off-by: Kevin O'Connor <kevin@koconnor.net>
|
|
Move many C files from the src/ directory to the new src/hw/ directory.
Signed-off-by: Kevin O'Connor <kevin@koconnor.net>
|
