Hi, On 2024-11-29 at 14:17:06, Linu Cherian (lcherian@xxxxxxxxxxx) wrote: > This patch series is rebased on coresight-next-v6.12.rc4 > > * Patches 1 & 2 adds support for allocation of trace buffer pages from reserved RAM > * Patches 3 & 4 adds support for saving metadata at the time of kernel panic > * Patch 5 adds support for reading trace data captured at the time of panic > * Patches 6 & 7 adds support for disabling coresight blocks at the time of panic > * Patch 8: Gives the full description about this feature as part of documentation > > V11 is posted here, > https://lore.kernel.org/linux-arm-kernel/20241111124746.2210378-1-lcherian@xxxxxxxxxxx/ > > Changelog from v11: > Convert all commands to literal code blocks, that was missed out in v11. > No other code changes. To make it clear, this is just some missed out fixes in Patch 8, Documentation. > > Changelog from v10: > * Converted all csdev_access_* to readl functions in tmc_panic_sync_* > * Added "tmc" prefix for register snapshots in struct tmc_crash_metadata > * Converted dev_info to dev_dbg in panic handlers > * Converted dsb to dmb in panic handlers > * Fixed marking metadata as invalid when a user is trying to use the > reserved buffer. Earlier this was wrongly set at the time of reading > reserved trace buffer. > * Moved common validation checks to is_tmc_crashdata_valid and minor > code rearrangements for efficiency > * Got rid of sink specific prepare/unprepare invocations > * Got rid of full from struct tmc_resrv_buf > * While reading crashdata, size is now calculated from metdata instead > of relying on reserved buffer size populated by dtb > * Minor documenation fixes > > Changelog from v9: > * Add common helper function of_tmc_get_reserved_resource_by_name > for better code reuse > * Reserved buffer validity and crashdata validity has been separated to > avoid interdependence > * New fields added to crash metadata: version, ffcr, ffsr, mode > * Version checks added for metadata validation > * Special file /dev/crash_tmc_xxx would be available only when > crash metadata is valid > * Removed READ_CRASHDATA mode meant for special casing crashdata reads. > Instead, dedicated read function added for crashdata reads from reserved > buffer which is common for both ETR and ETF sinks as well. > * Documentation added to Documentation/tracing/coresight/panic.rst > > Changelog from v8: > * Added missing exit path on error in __tmc_probe. > * Few whitespace fixes, checkpatch fixes. > * With perf sessions honouring stop_on_flush sysfs attribute, > removed redundant variable stop_on_flush_en. > > Changelog from v7: > * Fixed breakage on perf test -vvvv "arm coresight". > No issues seen with and without "resrv" buffer mode > * Moved the crashdev registration into a separate function. > * Removed redundant variable in tmc_etr_setup_crashdata_buf > * Avoided a redundant memcpy in tmc_panic_sync_etf. > * Tested kernel panic with trace session started uisng perf. > Please see the title "Perf based testing" below for details. > For this, stop_on_flush sysfs attribute is taken into > consideration while starting perf sessions as well. > > Changelog from v6: > * Added special device files for reading crashdata, so that > read_prevboot mode flag is removed. > * Added new sysfs TMC device attribute, stop_on_flush. > Stop on flush trigger event is disabled by default. > User need to explicitly enable this from sysfs for panic stop > to work. > * Address parameter for panicstop ETM configuration is > chosen as kernel "panic" address by default. > * Added missing tmc_wait_for_tmcready during panic handling > * Few other misc code rearrangements. > > Changelog from v5: > * Fixed issues reported by CONFIG_DEBUG_ATOMIC_SLEEP > * Fixed a memory leak while reading data from /dev/tmc_etrx in > READ_PREVBOOT mode > * Tested reading trace data from crashdump kernel > > Changelog from v4: > * Device tree binding > - Description is made more explicit on the usage of reserved memory > region > - Mismatch in memory region names in dts binding and driver fixed > - Removed "mem" suffix from the memory region names > * Rename "struct tmc_register_snapshot" -> "struct tmc_crash_metadata", > since it contains more than register snapshot. > Related variables are named accordingly. > * Rename struct tmc_drvdata members > resrv_buf -> crash_tbuf > metadata -> crash_mdata > * Size field in metadata refers to RSZ register and hence indicates the > size in 32 bit words. ETR metadata follows this convention, the same > has been extended to ETF metadata as well. > * Added crc32 for more robust metadata and tracedata validation. > * Added/modified dev_dbg messages during metadata validation > * Fixed a typo in patch 5 commit description > > Changelog from v3: > * Converted the Coresight ETM driver change to a named configuration. > RFC tag has been removed with this change. > * Fixed yaml issues reported by "make dt_binding_check" > * Added names for reserved memory regions 0 and 1 > * Added prevalidation checks for metadata processing > * Fixed a regression introduced in RFC v3 > - TMC Status register was getting saved wrongly > * Reverted memremap attribute changes from _WB to _WC to match > with the dma map attributes > * Introduced reserved buffer mode specific .sync op. > This fixes a possible crash when reserved buffer mode was used in > normal trace capture, due to unwanted dma maintenance operations. > > > > > Linu Cherian (8): > dt-bindings: arm: coresight-tmc: Add "memory-region" property > coresight: tmc-etr: Add support to use reserved trace memory > coresight: core: Add provision for panic callbacks > coresight: tmc: Enable panic sync handling > coresight: tmc: Add support for reading crash data > coresight: tmc: Stop trace capture on FlIn > coresight: config: Add preloaded configuration > Documentation: coresight: Panic support > > .../bindings/arm/arm,coresight-tmc.yaml | 26 ++ > Documentation/trace/coresight/panic.rst | 362 ++++++++++++++++++ > drivers/hwtracing/coresight/Makefile | 2 +- > .../coresight/coresight-cfg-preload.c | 2 + > .../coresight/coresight-cfg-preload.h | 2 + > .../hwtracing/coresight/coresight-cfg-pstop.c | 83 ++++ > drivers/hwtracing/coresight/coresight-core.c | 42 ++ > .../hwtracing/coresight/coresight-tmc-core.c | 326 +++++++++++++++- > .../hwtracing/coresight/coresight-tmc-etf.c | 92 ++++- > .../hwtracing/coresight/coresight-tmc-etr.c | 181 ++++++++- > drivers/hwtracing/coresight/coresight-tmc.h | 104 +++++ > include/linux/coresight.h | 12 + > 12 files changed, 1222 insertions(+), 12 deletions(-) > create mode 100644 Documentation/trace/coresight/panic.rst > create mode 100644 drivers/hwtracing/coresight/coresight-cfg-pstop.c > > -- > 2.34.1 > >
