Re: [PATCHv3 0/5] arm-cci400: PMU monitoring support on ARM64
From: Nicolas Pitre
Date: Tue Mar 10 2015 - 12:09:54 EST
On Tue, 10 Mar 2015, Suzuki K. Poulose wrote:
> From: "Suzuki K. Poulose" <suzuki.poulose@xxxxxxx>
> This series enables the PMU monitoring support for CCI400 on ARM64.
> The existing CCI400 driver code is a mix of PMU driver and the MCPM
> driver code. The MCPM driver is only used on ARM(32) and contains
> arm32 assembly and hence can't be built on ARM64. This patch splits
> the code to
> - ARM_CCI400_PORT_CTRL driver - depends on ARM && V7
> - ARM_CCI400_PMU driver
> Accessing the Peripheral ID2 register(PID2) on CCI-400, to detect
> the revision of the chipset, is a secure operation. Hence, it prevents
> us from running this on non-secure platforms. The issue is overcome by
> explicitly mentioning the revision number of the CCI PMU in the device tree
> binding. The device-tree binding has been updated with the new bindings.
> i.e, arm-cci-400-pmu,r0 => revision 0
> arm-cci-400-pmu,r1 => revision 1
> arm-cci-400-pmu => (old) DEPRECATED
> The old binding has been DEPRECATED and must be used only on ARM32
> system with secure access. We don't have a reliable dynamic way to detect
> if the system is running secure. This series tries to use the best safe
> method by relying on the availability of MCPM(as it was prior to the series).
> It is upto the MCPM platform driver to decide, if the system is secure before
> it goes ahead and registers its drivers and pokes the CCI. This series doesn't
> address/solve the problem of MCPM. I will be happy to use a better approach,
> if there is any.
> Tested on (non-secure)TC2 and A53x2.
Would be nice if you could also test it on secure TC2 making sure MCPM
is still functional.
For patches 1, 3 and 4, you may add:
Acked-by: Nicolas Pitre <nico@xxxxxxxxxx>
Patches 2 and 5 are purely PMU stuff and out of my area of expertise.
> Changes sinve V2
> - Include suggestions from Sudeep Holla.
> - Cleanup event validation checks.
> Changes since V1 (Suggestions from Nicolas Pitre):
> - Split Patch 2 to separate the 'PMU' abstraction(now Patch 2/5)
> from the introduction of a new device-tree binding(now Patch 3/5)
> - Rename
> ARM_CCI400_MCPM => ARM_CCI400_PORT_CTRL
> CCI400_MCPM_PORTS_DATA => CCI400_PORTS_DATA
> - Select ARM_CCI400_COMMON for ARM_CCI400_PORT_CTRL
> - Better documentation in the git commit log about the ARM_CCI config.
> - Move the 'pr_info' to its apporpriate patch.
> Suzuki K. Poulose (5):
> arm-cci: Rearrange code for splitting PMU vs driver code
> arm-cci: Abstract the CCI400 PMU speicific definitions
> arm-cci: Get rid of secure transactions for PMU driver
> arm-cci: Split the code for PMU vs driver support
> arm-cci: Fix CCI PMU event validation
> Documentation/devicetree/bindings/arm/cci.txt | 7 +-
> arch/arm/include/asm/arm-cci.h | 42 +++
> arch/arm/mach-exynos/Kconfig | 2 +-
> arch/arm/mach-vexpress/Kconfig | 4 +-
> arch/arm64/include/asm/arm-cci.h | 27 ++
> drivers/bus/Kconfig | 28 +-
> drivers/bus/arm-cci.c | 496 ++++++++++++++-----------
> include/linux/arm-cci.h | 9 +-
> 8 files changed, 384 insertions(+), 231 deletions(-)
> create mode 100644 arch/arm/include/asm/arm-cci.h
> create mode 100644 arch/arm64/include/asm/arm-cci.h
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