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authorPeter Maydell <peter.maydell@linaro.org>2019-05-24 10:16:29 +0100
committerPeter Maydell <peter.maydell@linaro.org>2019-05-24 10:16:29 +0100
commitceac83e9ba724d915353d740a11ca08670deea59 (patch)
treedecd96395ed9a088790fafd0b503821264e5e5c9 /include/hw/timer/armv7m_systick.h
parent8dc7fd56dd4f56ab8ff1df3765ae6b5d3ac11c5e (diff)
parent98e4f4fdb8ea05d840f51f47125924c2bb9df2df (diff)
downloadfocaccia-qemu-ceac83e9ba724d915353d740a11ca08670deea59.tar.gz
focaccia-qemu-ceac83e9ba724d915353d740a11ca08670deea59.zip
Merge remote-tracking branch 'remotes/pmaydell/tags/pull-target-arm-20190523' into staging
target-arm queue:
 * exynos4210: QOM'ify the Exynos4210 SoC
 * exynos4210: Add DMA support for the Exynos4210
 * arm_gicv3: Fix writes to ICC_CTLR_EL3
 * arm_gicv3: Fix write of ICH_VMCR_EL2.{VBPR0, VBPR1}
 * target/arm: Fix vector operation segfault
 * target/arm: Minor improvements to BFXIL, EXTR

# gpg: Signature made Thu 23 May 2019 15:22:55 BST
# gpg:                using RSA key E1A5C593CD419DE28E8315CF3C2525ED14360CDE
# gpg:                issuer "peter.maydell@linaro.org"
# gpg: Good signature from "Peter Maydell <peter.maydell@linaro.org>" [ultimate]
# gpg:                 aka "Peter Maydell <pmaydell@gmail.com>" [ultimate]
# gpg:                 aka "Peter Maydell <pmaydell@chiark.greenend.org.uk>" [ultimate]
# Primary key fingerprint: E1A5 C593 CD41 9DE2 8E83  15CF 3C25 25ED 1436 0CDE

* remotes/pmaydell/tags/pull-target-arm-20190523:
  hw/arm/exynos4210: QOM'ify the Exynos4210 SoC
  hw/arm/exynos4210: Add DMA support for the Exynos4210
  hw/arm/exynos4: Use the IEC binary prefix definitions
  hw/arm/exynos4: Remove unuseful debug code
  hw/intc/arm_gicv3: Fix writes to ICC_CTLR_EL3
  hw/intc/arm_gicv3: Fix write of ICH_VMCR_EL2.{VBPR0, VBPR1}
  arm: Rename hw/arm/arm.h to hw/arm/boot.h
  arm: Remove unnecessary includes of hw/arm/arm.h
  arm: Move system_clock_scale to armv7m_systick.h
  target/arm: Fix vector operation segfault
  target/arm: Simplify BFXIL expansion
  target/arm: Use extract2 for EXTR

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Diffstat (limited to 'include/hw/timer/armv7m_systick.h')
-rw-r--r--include/hw/timer/armv7m_systick.h22
1 files changed, 22 insertions, 0 deletions
diff --git a/include/hw/timer/armv7m_systick.h b/include/hw/timer/armv7m_systick.h
index cca04defd8..25e5ceacc8 100644
--- a/include/hw/timer/armv7m_systick.h
+++ b/include/hw/timer/armv7m_systick.h
@@ -31,4 +31,26 @@ typedef struct SysTickState {
     qemu_irq irq;
 } SysTickState;
 
+/*
+ * Multiplication factor to convert from system clock ticks to qemu timer
+ * ticks. This should be set (by board code, usually) to a value
+ * equal to NANOSECONDS_PER_SECOND / frq, where frq is the clock frequency
+ * in Hz of the CPU.
+ *
+ * This value is used by the systick device when it is running in
+ * its "use the CPU clock" mode (ie when SYST_CSR.CLKSOURCE == 1) to
+ * set how fast the timer should tick.
+ *
+ * TODO: we should refactor this so that rather than using a global
+ * we use a device property or something similar. This is complicated
+ * because (a) the property would need to be plumbed through from the
+ * board code down through various layers to the systick device
+ * and (b) the property needs to be modifiable after realize, because
+ * the stellaris board uses this to implement the behaviour where the
+ * guest can reprogram the PLL registers to downclock the CPU, and the
+ * systick device needs to react accordingly. Possibly this should
+ * be deferred until we have a good API for modelling clock trees.
+ */
+extern int system_clock_scale;
+
 #endif