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From: Mike Leach <>
Subject: [PATCH v4 0/3] Update AMBA driver for enhanced component ID spec.
Date: Wed, 30 Jan 2019 23:40:48 +0000
Message-ID: <> (raw)

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

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. 


Tested on DB410, Juno; kernel 5.0-rc4

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
  drivers: amba: Update component matching to use the CoreSight UCI
  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(-)


             reply index

Thread overview: 6+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-01-30 23:40 Mike Leach [this message]
2019-01-30 23:40 ` [PATCH v4 1/3] drivers: amba: Updates to component identification for driver matching Mike Leach
2019-01-31 11:23   ` Sai Prakash Ranjan
2019-01-30 23:40 ` [PATCH v4 2/3] drivers: amba: Update component matching to use the CoreSight UCI values Mike Leach
2019-01-30 23:40 ` [PATCH v4 3/3] coresight: etmv4: Update ID register table to add UCI support Mike Leach
2019-02-06 20:58 ` [PATCH v4 0/3] Update AMBA driver for enhanced component ID spec Mathieu Poirier

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