1. 24 9月, 2016 1 次提交
    • S
      arm64: arch_timer: Work around QorIQ Erratum A-008585 · f6dc1576
      Scott Wood 提交于
      Erratum A-008585 says that the ARM generic timer counter "has the
      potential to contain an erroneous value for a small number of core
      clock cycles every time the timer value changes".  Accesses to TVAL
      (both read and write) are also affected due to the implicit counter
      read.  Accesses to CVAL are not affected.
      
      The workaround is to reread TVAL and count registers until successive
      reads return the same value.  Writes to TVAL are replaced with an
      equivalent write to CVAL.
      
      The workaround is to reread TVAL and count registers until successive reads
      return the same value, and when writing TVAL to retry until counter
      reads before and after the write return the same value.
      
      The workaround is enabled if the fsl,erratum-a008585 property is found in
      the timer node in the device tree.  This can be overridden with the
      clocksource.arm_arch_timer.fsl-a008585 boot parameter, which allows KVM
      users to enable the workaround until a mechanism is implemented to
      automatically communicate this information.
      
      This erratum can be found on LS1043A and LS2080A.
      Acked-by: NMarc Zyngier <marc.zyngier@arm.com>
      Signed-off-by: NScott Wood <oss@buserror.net>
      [will: renamed read macro to reflect that it's not usually unstable]
      Signed-off-by: NWill Deacon <will.deacon@arm.com>
      f6dc1576
  2. 17 8月, 2016 3 次提交
  3. 01 8月, 2016 1 次提交
    • M
      clocksource/arm_arch_timer: Force per-CPU interrupt to be level-triggered · f005bd7e
      Marc Zyngier 提交于
      The ARM architected timer produces level-triggered interrupts (this
      is mandated by the architecture). Unfortunately, a number of
      device-trees get this wrong, and expose an edge-triggered interrupt.
      
      Until now, this wasn't too much an issue, as the programming of the
      trigger would fail (the corresponding PPI cannot be reconfigured),
      and the kernel would be happy with this. But we're about to change
      this, and trust DT a lot if the driver doesn't provide its own
      trigger information. In that context, the timer breaks badly.
      
      While we do need to fix the DTs, there is also some userspace out
      there (kvmtool) that generates the same kind of broken DT on the
      fly, and that will completely break with newer kernels.
      
      As a safety measure, and to keep buggy software alive as well as
      buying us some time to fix DTs all over the place, let's check
      what trigger configuration has been given us by the firmware.
      If this is not a level configuration, then we know that the
      DT/ACPI configuration is bust, and we pick some defaults which
      won't be worse than the existing setup.
      Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com>
      Cc: Andrew Lunn <andrew@lunn.ch>
      Cc: Liu Gang <Gang.Liu@nxp.com>
      Cc: Mark Rutland <marc.rutland@arm.com>
      Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
      Cc: Wenbin Song <Wenbin.Song@freescale.com>
      Cc: Mingkai Hu <Mingkai.Hu@freescale.com>
      Cc: Florian Fainelli <f.fainelli@gmail.com>
      Cc: Kevin Hilman <khilman@baylibre.com>
      Cc: Daniel Lezcano <daniel.lezcano@linaro.org>
      Cc: Michal Simek <michal.simek@xilinx.com>
      Cc: Jon Hunter <jonathanh@nvidia.com>
      Cc: arm@kernel.org
      Cc: bcm-kernel-feedback-list@broadcom.com
      Cc: linux-arm-kernel@lists.infradead.org
      Cc: Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com>
      Cc: Jason Cooper <jason@lakedaemon.net>
      Cc: Ray Jui <rjui@broadcom.com>
      Cc: "Hou Zhiqiang" <B48286@freescale.com>
      Cc: Tirumalesh Chalamarla <tchalamarla@cavium.com>
      Cc: linux-samsung-soc@vger.kernel.org
      Cc: Yuan Yao <yao.yuan@nxp.com>
      Cc: Jan Glauber <jglauber@cavium.com>
      Cc: Gregory Clement <gregory.clement@free-electrons.com>
      Cc: linux-amlogic@lists.infradead.org
      Cc: soren.brinkmann@xilinx.com
      Cc: Rajesh Bhagat <rajesh.bhagat@freescale.com>
      Cc: Scott Branden <sbranden@broadcom.com>
      Cc: Duc Dang <dhdang@apm.com>
      Cc: Kukjin Kim <kgene@kernel.org>
      Cc: Carlo Caione <carlo@caione.org>
      Cc: Dinh Nguyen <dinguyen@opensource.altera.com>
      Link: http://lkml.kernel.org/r/1470045256-9032-2-git-send-email-marc.zyngier@arm.comSigned-off-by: NThomas Gleixner <tglx@linutronix.de>
      f005bd7e
  4. 15 7月, 2016 9 次提交
  5. 12 7月, 2016 1 次提交
  6. 07 7月, 2016 1 次提交
  7. 06 7月, 2016 1 次提交
  8. 28 6月, 2016 23 次提交