These patches improve timekeeping of MIPS/Malta kernels running in a KVM guest.
Patch 2 fixes malta frequency calculation under virtualisation, especially on very slow targets (FPGA / emulators). Patch 1 is a minor fix for something I noticed while writing patch 2. Patch 3 drops the use of the PIT timer for Malta, which is slow to emulate with KVM + QEMU. Finally patch 4 calculates min_delta_ns of cevt-r4k dynamically to handle virtualised environments with software emulated Count/Compare, and where Count frequency may not be directly related to actual CPU speed (and so the static value of 0x300 may be no good). James Hogan (4): MIPS: malta-time: Start GIC count before syncing to RTC MIPS: malta-time: Take seconds into account MIPS: malta-time: Don't use PIT timer for cevt/csrc MIPS: cevt-r4k: Dynamically calculate min_delta_ns arch/mips/Kconfig | 1 - arch/mips/kernel/cevt-r4k.c | 82 +++++++++++++++++++++++++++++++++++++++- arch/mips/mti-malta/malta-time.c | 50 +++++++++++++++--------- 3 files changed, 113 insertions(+), 20 deletions(-) Cc: Ralf Baechle <r...@linux-mips.org> Cc: Daniel Lezcano <daniel.lezc...@linaro.org> Cc: Thomas Gleixner <t...@linutronix.de> Cc: linux-m...@linux-mips.org Cc: linux-kernel@vger.kernel.org -- 2.4.10
