The latest ARM CoreSight specification updates the component identification requirements for all components attached to an AMBA bus. (ARM IHI 0029E)
This specification defines bits 15:12 in the ComponentID (CID) value as the device class. Identification requirements now depend on this class. Class 0xF: Traditional components identified by Peripheral ID (PID) only. Class 0x9: CoreSight components may be identified by a Universal Component Identifier (UCI) consisting of the PID plus CoreSight DevType and DevArch values.
Current and future ARM CoreSight IP will now use the same PID for components on the same function - e.g. the ETM, CTI, PMU and Debug elements associated with a core. The first core to use this UCI method is the A35, which currently has binding entries in the ETMv4 driver.
This patchset prepares for the addition of the upcoming CTI driver, which will need to correctly bind with A35, and reported new devices that share PID for multiple components, while overcoming the limitation of binding by PID alone, which cannot now work.
Patch 0001: Adds new UCI data structure and uses it with existing drivers that use private data field in amba_id. This fixes issue from prior set. Patch 0002: Implements the UCI matching code in the AMBA core code. Patch 0003: Update ETMv4 driver to use UCI as appropriate.
Thanks Mike
Tested on DB410, Juno; kernel 5.0-rc6
Changes since v4: re-based on 5.0-rc6 Added reviewed/tested by tags.
Changes since v3: Fix UCI structure to allow CoreSight drivers to set private data. This fixes bug where none-UCI private data would cause a driver binding mismatch. (e.g. STM).
Add CS_AMBA macros to simplify building AMBA ID tables, with and without UCI settings.
Changes since v2: Simplification of amba_cs_uci_id_match(). Fix CID class bitfield comments. Dropped RFC tag on patchset.
Mike Leach (3): drivers: amba: Updates to component identification for driver matching. drivers: amba: Update component matching to use the CoreSight UCI values. coresight: etmv4: Update ID register table to add UCI support
drivers/amba/bus.c | 45 +++++++++++++++---- drivers/hwtracing/coresight/coresight-etm3x.c | 44 ++++++------------ drivers/hwtracing/coresight/coresight-etm4x.c | 21 +++++---- drivers/hwtracing/coresight/coresight-priv.h | 40 +++++++++++++++++ drivers/hwtracing/coresight/coresight-stm.c | 14 ++---- drivers/hwtracing/coresight/coresight-tmc.c | 30 ++++--------- include/linux/amba/bus.h | 39 ++++++++++++++++ 7 files changed, 153 insertions(+), 80 deletions(-)