[U-Boot] [PATCH v6 0/2] timer: Add High Precision Event Timers (HPET) support

Ivan Gorinov ivan.gorinov at intel.com
Thu Apr 12 22:11:58 UTC 2018


Add HPET driver as an alternative timer for x86 (default is TSC).
HPET counter has constant frequency and does not need calibration.
This change also makes TSC timer driver optional on x86.
New HPET driver can also be selected as the early timer on x86.

v6:
    Added TSC-specific timer functions to use instead of early timer
    in the code that specifically needs TSC.

v5:
    Using readq() and writeq() for main counter access.

v3:
    Added early timer choice in x86 Kconfig.

Ivan Gorinov (2):
  x86: Add TSC-specific timer functions
  timer: Add High Precision Event Timers (HPET) support

 arch/Kconfig                      |   1 +
 arch/x86/Kconfig                  |  21 ++++
 arch/x86/cpu/coreboot/timestamp.c |   2 +-
 arch/x86/cpu/quark/mrc_util.c     |  13 ++-
 arch/x86/dts/hpet.dtsi            |   7 ++
 arch/x86/include/asm/u-boot-x86.h |   2 +-
 common/Kconfig                    |   1 +
 drivers/timer/Kconfig             |   9 ++
 drivers/timer/Makefile            |   1 +
 drivers/timer/hpet_timer.c        | 209 ++++++++++++++++++++++++++++++++++++++
 drivers/timer/tsc_timer.c         |  39 +++++--
 11 files changed, 288 insertions(+), 17 deletions(-)
 create mode 100644 arch/x86/dts/hpet.dtsi
 create mode 100644 drivers/timer/hpet_timer.c

-- 
2.7.4



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