[PATCHv3 0/5] arm-cci400: PMU monitoring support on ARM64
Suzuki K. Poulose
suzuki.poulose at arm.com
Tue Mar 10 08:18:50 PDT 2015
From: "Suzuki K. Poulose" <suzuki.poulose at arm.com>
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.
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)
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
More information about the linux-arm-kernel