All the devices that used to use system_clock_scale have now been
converted to use Clock inputs instead, so the global is no longer
needed; remove it and all the code that sets it.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-id: 20210812093356.1946-26-peter.maydell@linaro.org
The v7M systick timer can be programmed to run from either of
two clocks:
* an "external reference clock" (when SYST_CSR.CLKSOURCE == 0)
* the main CPU clock (when SYST_CSR.CLKSOURCE == 1)
Our implementation currently hardwires the external reference clock
to be 1MHz, and allows boards to set the main CPU clock frequency via
the global 'system_clock_scale'. (Most boards set that to a constant
value; the Stellaris boards allow the guest to reprogram it via the
board-specific RCC registers).
As the first step in converting this to use the Clock infrastructure,
add input clocks to the systick device for the reference clock and
the CPU clock. The device implementation ignores them; once we have
made all the users of the device correctly wire up the new Clocks we
will switch the implementation to use them and ignore the old
system_clock_scale.
This is a migration compat break for all M-profile boards, because of
the addition of the new clock objects to the vmstate struct.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Luc Michel <luc@lmichel.fr>
Message-id: 20210812093356.1946-6-peter.maydell@linaro.org
Add the usual-style QEMU interface comment documenting what
properties, etc, this device exposes.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Luc Michel <luc@lmichel.fr>
Message-id: 20210812093356.1946-5-peter.maydell@linaro.org
The armv7m systick timer is a 24-bit decrementing, wrap-on-zero,
clear-on-write counter. Our current implementation has various
bugs and dubious workarounds in it (for instance see
https://bugs.launchpad.net/qemu/+bug/1872237).
We have an implementation of a simple decrementing counter
and we put a lot of effort into making sure it handles the
interesting corner cases (like "spend a cycle at 0 before
reloading") -- ptimer.
Rewrite the systick timer to use a ptimer rather than
a raw QEMU timer.
Unfortunately this is a migration compatibility break,
which will affect all M-profile boards.
Among other bugs, this fixes
https://bugs.launchpad.net/qemu/+bug/1872237 :
now writes to SYST_CVR when the timer is enabled correctly
do nothing; when the timer is enabled via SYST_CSR.ENABLE,
the ptimer code will (because of POLICY_NO_IMMEDIATE_RELOAD)
arrange that after one timer tick the counter is reloaded
from SYST_RVR and then counts down from there, as the
architecture requires.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-id: 20201015151829.14656-3-peter.maydell@linaro.org
Some typedefs and macros are defined after the type check macros.
This makes it difficult to automatically replace their
definitions with OBJECT_DECLARE_TYPE.
Patch generated using:
$ ./scripts/codeconverter/converter.py -i \
--pattern=QOMStructTypedefSplit $(git grep -l '' -- '*.[ch]')
which will split "typdef struct { ... } TypedefName"
declarations.
Followed by:
$ ./scripts/codeconverter/converter.py -i --pattern=MoveSymbols \
$(git grep -l '' -- '*.[ch]')
which will:
- move the typedefs and #defines above the type check macros
- add missing #include "qom/object.h" lines if necessary
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Message-Id: <20200831210740.126168-9-ehabkost@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Message-Id: <20200831210740.126168-10-ehabkost@redhat.com>
Message-Id: <20200831210740.126168-11-ehabkost@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
The system_clock_scale global is used only by the armv7m systick
device; move the extern declaration to the armv7m_systick.h header,
and expand the comment to explain what it is and that it should
ideally be replaced with a different approach.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Tested-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-id: 20190516163857.6430-2-peter.maydell@linaro.org
The SysTick timer isn't really part of the NVIC proper;
we just modelled it that way back when we couldn't
easily have devices that only occupied a small chunk
of a memory region. Split it out into its own device.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 1487604965-23220-10-git-send-email-peter.maydell@linaro.org
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
