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2022-02-08hw/timer/armv7m_systick: Update clock source before enabling timerRichard Petri
Starting the SysTick timer and changing the clock source a the same time will result in an error, if the previous clock period was zero. For exmaple, on the mps2-tz platforms, no refclk is present. Right after reset, the configured ptimer period is zero, and trying to enabling it will turn it off right away. E.g., code running on the platform setting SysTick->CTRL = SysTick_CTRL_CLKSOURCE_Msk | SysTick_CTRL_ENABLE_Msk; should change the clock source and enable the timer on real hardware, but resulted in an error in qemu. Signed-off-by: Richard Petri <git@rpls.de> Reviewed-by: Peter Maydell <peter.maydell@linaro.org> Message-id: 20220201192650.289584-1-git@rpls.de Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2021-09-01arm: Remove system_clock_scale globalPeter Maydell
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
2021-09-01hw/timer/armv7m_systick: Use clock inputs instead of system_clock_scalePeter Maydell
Now that all users of the systick devices wire up the clock inputs, use those instead of the system_clock_scale and the hardwired 1MHz value for the reference clock. This will fix various board models where we were incorrectly providing a 1MHz reference clock instead of some other value or instead of providing no reference clock at all. Signed-off-by: Peter Maydell <peter.maydell@linaro.org> Reviewed-by: Damien Hedde <damien.hedde@greensocs.com> Message-id: 20210812093356.1946-22-peter.maydell@linaro.org
2021-09-01hw/timer/armv7m_systick: Add input clocksPeter Maydell
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
2020-10-27hw/timer/armv7m_systick: Rewrite to use ptimersPeter Maydell
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
2020-09-14hw/timer/armv7m_systick: assert that board code set system_clock_scalePeter Maydell
It is the responsibility of board code for an armv7m system to set system_clock_scale appropriately for the CPU speed of the core. If it forgets to do this, then QEMU will hang if the guest tries to use the systick timer in the "tick at the CPU clock frequency" mode. We forgot that in a couple of our boards (see commits ce4f70e81ed23c93f, e7e5a9595ab1136). Add an assertion in the systick reset method so we don't let any new boards in with the same bug. Signed-off-by: Peter Maydell <peter.maydell@linaro.org> Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org> Message-id: 20200825160847.18091-1-peter.maydell@linaro.org
2020-02-07armv7m_systick: delay timer_new to avoid memleaksPan Nengyuan
There is a memory leak when we call 'device_list_properties' with typename = armv7m_systick. It's easy to reproduce as follow: virsh qemu-monitor-command vm1 --pretty '{"execute": "device-list-properties", "arguments": {"typename": "armv7m_systick"}}' This patch delay timer_new to fix this memleaks. Reported-by: Euler Robot <euler.robot@huawei.com> Signed-off-by: Pan Nengyuan <pannengyuan@huawei.com> Message-id: 20200205070659.22488-2-pannengyuan@huawei.com Cc: qemu-arm@nongnu.org Reviewed-by: Peter Maydell <peter.maydell@linaro.org> Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2019-08-16Include migration/vmstate.h lessMarkus Armbruster
In my "build everything" tree, changing migration/vmstate.h triggers a recompile of some 2700 out of 6600 objects (not counting tests and objects that don't depend on qemu/osdep.h). hw/hw.h supposedly includes it for convenience. Several other headers include it just to get VMStateDescription. The previous commit made that unnecessary. Include migration/vmstate.h only where it's still needed. Touching it now recompiles only some 1600 objects. Signed-off-by: Markus Armbruster <armbru@redhat.com> Reviewed-by: Alistair Francis <alistair.francis@wdc.com> Message-Id: <20190812052359.30071-16-armbru@redhat.com> Tested-by: Philippe Mathieu-Daudé <philmd@redhat.com>
2019-08-16Include hw/irq.h a lot lessMarkus Armbruster
In my "build everything" tree, changing hw/irq.h triggers a recompile of some 5400 out of 6600 objects (not counting tests and objects that don't depend on qemu/osdep.h). hw/hw.h supposedly includes it for convenience. Several other headers include it just to get qemu_irq and.or qemu_irq_handler. Move the qemu_irq and qemu_irq_handler typedefs from hw/irq.h to qemu/typedefs.h, and then include hw/irq.h only where it's still needed. Touching it now recompiles only some 500 objects. Signed-off-by: Markus Armbruster <armbru@redhat.com> Reviewed-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com> Tested-by: Philippe Mathieu-Daudé <philmd@redhat.com> Message-Id: <20190812052359.30071-13-armbru@redhat.com>
2019-07-04hw/timer/armv7m_systick: Forbid non-privileged accessesPeter Maydell
Like most of the v7M memory mapped system registers, the systick registers are accessible to privileged code only and user accesses must generate a BusFault. We implement that for registers in the NVIC proper already, but missed it for systick since we implement it as a separate device. Correct the omission. Signed-off-by: Peter Maydell <peter.maydell@linaro.org> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com> Message-id: 20190617175317.27557-6-peter.maydell@linaro.org
2019-06-12Include qemu/module.h where needed, drop it from qemu-common.hMarkus Armbruster
Signed-off-by: Markus Armbruster <armbru@redhat.com> Message-Id: <20190523143508.25387-4-armbru@redhat.com> [Rebased with conflicts resolved automatically, except for hw/usb/dev-hub.c hw/misc/exynos4210_rng.c hw/misc/bcm2835_rng.c hw/misc/aspeed_scu.c hw/display/virtio-vga.c hw/arm/stm32f205_soc.c; ui/cocoa.m fixed up]
2017-02-28armv7m: Split systick out from NVICPeter Maydell
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>