jcs.org
qemu with hax to log dma reads & writes
jcs.org/2018/11/12/vfio
arm: Move system_clock_scale to armv7m_systick.h
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
+22
-4
-4
include/hw/arm/arm.h
-4
include/hw/arm/arm.h
+22
include/hw/timer/armv7m_systick.h
+22
include/hw/timer/armv7m_systick.h
···
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qemu_irq irq;
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} SysTickState;
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/*
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* Multiplication factor to convert from system clock ticks to qemu timer
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* ticks. This should be set (by board code, usually) to a value
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* equal to NANOSECONDS_PER_SECOND / frq, where frq is the clock frequency
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* in Hz of the CPU.
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*
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* This value is used by the systick device when it is running in
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* its "use the CPU clock" mode (ie when SYST_CSR.CLKSOURCE == 1) to
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* set how fast the timer should tick.
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*
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* TODO: we should refactor this so that rather than using a global
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* we use a device property or something similar. This is complicated
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* because (a) the property would need to be plumbed through from the
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* board code down through various layers to the systick device
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* and (b) the property needs to be modifiable after realize, because
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* the stellaris board uses this to implement the behaviour where the
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* guest can reprogram the PLL registers to downclock the CPU, and the
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* systick device needs to react accordingly. Possibly this should
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* be deferred until we have a good API for modelling clock trees.
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*/
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extern int system_clock_scale;
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#endif