On early boot stages STM32MP1 platform is able to dedicate some hardware blocks to a secure OS running in TrustZone. We need to avoid using those hardware blocks on non-secure context (i.e. kernel) because read/write access will all be discarded. Extended TrustZone Protection driver register itself as listener of BUS_NOTIFY_BIND_DRIVER and check, given the device address, if the hardware block could be used in a Linux context. If not it returns NOTIFY_BAD to driver core to stop driver probing. NOTE: patches 2 and 3 should be applied only on git://git.kernel.org/pub/scm/linux/kernel/git/atorgue/stm32.git stm32-next but until this patch: https://lkml.org/lkml/2018/2/26/386 find it way to mailine KBuild will complain about them. Benjamin Gaignard (3): driver core: check notifier_call_chain return value dt-bindings: stm32: Add bindings for Extended TrustZone Protection ARM: mach-stm32: Add Extended TrustZone Protection driver .../bindings/arm/stm32/st,stm32mp1-etzpc.txt | 13 ++ arch/arm/mach-stm32/Kconfig | 7 + arch/arm/mach-stm32/Makefile | 1 + arch/arm/mach-stm32/stm32-etzpc.c | 252 +++++++++++++++++++++ drivers/base/dd.c | 9 +- 5 files changed, 279 insertions(+), 3 deletions(-) create mode 100644 Documentation/devicetree/bindings/arm/stm32/st,stm32mp1-etzpc.txt create mode 100644 arch/arm/mach-stm32/stm32-etzpc.c -- 2.15.0 -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
