[PATCH v3 0/3] Exynos MCT udelay, MCT cleanup, MCT to 32-bits

Doug Anderson dianders at chromium.org
Fri Jun 20 10:47:49 PDT 2014

This is a series of 3 patches related to the exynos MCT (multi core
timer).  The first allows MCT to function as a udelay() timer which
fixes broken udelay on 5400, 5800, and even (to a lesser extent) on
5250.  The second is some general cleanup.  The third moves MCT to
32-bits where possible to give us a nice speedup.

The first probably ought to be destined for 3.16 as a bugfix whereas
the others could land in a future kernel release.

This series is based on (clocksource: exynos_mct: Fix ftrace).

With this series we can drop the patches I submitted:
- clocksource: exynos_mct: cache mct upper count
- clocksource: exynos_mct: Optimize register reads with ldmia

Changes in v3:
- Back to exynos_frc_read for now until 32/64 is resolved.
- Now returns cycles_t which matches arch/arm/include/asm/timex.h.
- Rebased.
- Moved registration to its own function.
- __raw_readl / __raw_writel patch new for version 3
- Now 32-bit version instead of ldmia version

Changes in v2:
- Added #defines for ARM and ARM64 as pointed by Doug Anderson.

Amit Daniel Kachhap (1):
  clocksource: exynos_mct: Register the timer for stable udelay

Doug Anderson (2):
  clocksource: exynos_mct: __raw_readl/__raw_writel =>
  clocksource: exynos_mct: Only use 32-bits where possible

 drivers/clocksource/Kconfig      |  1 +
 drivers/clocksource/exynos_mct.c | 72 ++++++++++++++++++++++++++++++----------
 2 files changed, 55 insertions(+), 18 deletions(-)


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