kernel/arch/powerpc/platforms/pseries/pseries_energy.c, branch linux-6.2.y

powerpc/pseries: Fix drc-info mappings of logical cpus to drc-index

2019-11-13T05:57:57Z

There are a couple subtle errors in the mapping between cpu-ids and a cpus associated drc-index when using the new ibm,drc-info property. The first is that while drc-info may have been a supported firmware feature at boot it is possible we have migrated to a CEC with older firmware that doesn't support the ibm,drc-info property. In that case the device tree would have been updated after migration to remove the ibm,drc-info property and replace it with the older style ibm,drc-* properties for types, indexes, names, and power-domains. PAPR even goes as far as dictating that if we advertise support for drc-info that we are capable of supporting either property type at runtime. The second is that the first value of the ibm,drc-info property is the int encoded count of drc-info entries. As such "value" returned by of_prop_next_u32() is pointing at that count, and not the first element of the first drc-info entry as is expected by the of_read_drc_info_cell() helper. Fix the first by ignoring DRC-INFO firmware feature and instead testing directly for ibm,drc-info, and then falling back to the old style ibm,drc-indexes in the case it doesn't exit. Fix the second by incrementing value to the next element prior to parsing drc-info entries. Signed-off-by: Tyrel Datwyler Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/1573449697-5448-3-git-send-email-tyreld@linux.ibm.com

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500

2019-06-19T15:09:55Z

Based on 2 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license version 2 as published by the free software foundation this program is free software you can redistribute it and or modify it under the terms of the gnu general public license version 2 as published by the free software foundation # extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 4122 file(s). Signed-off-by: Thomas Gleixner Reviewed-by: Enrico Weigelt Reviewed-by: Kate Stewart Reviewed-by: Allison Randal Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190604081206.933168790@linutronix.de Signed-off-by: Greg Kroah-Hartman

powerpc/pseries/energy: Use OF accessor functions to read ibm,drc-indexes

2019-03-26T23:40:09Z

In cpu_to_drc_index() in the case when FW_FEATURE_DRC_INFO is absent, we currently use of_read_property() to obtain the pointer to the array corresponding to the property "ibm,drc-indexes". The elements of this array are of type __be32, but are accessed without any conversion to the OS-endianness, which is buggy on a Little Endian OS. Fix this by using of_property_read_u32_index() accessor function to safely read the elements of the array. Fixes: e83636ac3334 ("pseries/drc-info: Search DRC properties for CPU indexes") Cc: stable@vger.kernel.org # v4.16+ Reported-by: Pavithra R. Prakash Signed-off-by: Gautham R. Shenoy Reviewed-by: Vaidyanathan Srinivasan [mpe: Make the WARN_ON a WARN_ON_ONCE so it's not retriggerable] Signed-off-by: Michael Ellerman

pseries/drc-info: Search DRC properties for CPU indexes

2018-01-21T05:21:46Z

pseries/drc-info: Provide parallel routines to convert between drc_index and CPU numbers at runtime, using the older device-tree properties ("ibm,drc-indexes", "ibm,drc-names", "ibm,drc-types" and "ibm,drc-power-domains"), or the new property "ibm,drc-info". Signed-off-by: Michael Bringmann Signed-off-by: Michael Ellerman

powerpc/pseries: Don't print failure message in energy driver

2017-08-10T12:30:29Z

This driver currently reports the H_BEST_ENERGY hypervisor call is unsupported (even when booting in a non-virtualised environment). This is not something the administrator can do much with, and not significant for debugging. Remove it. Signed-off-by: Nicholas Piggin Reviewed-by: Vaidyanathan Srinivasan Signed-off-by: Michael Ellerman

powerpc/sparse: make some things static

2016-06-16T12:23:11Z

This is just a smattering of things picked up by sparse that should be made static. Signed-off-by: Daniel Axtens Signed-off-by: Michael Ellerman

powerpc: Fix a number of sparse warnings

2013-08-14T01:50:24Z

Address some of the trivial sparse warnings in arch/powerpc. Signed-off-by: Anton Blanchard Signed-off-by: Benjamin Herrenschmidt

powerpc/pseries: Cleanup best_energy_hcall detection

2013-01-10T04:08:37Z

Currently we search for the best_energy hcall using a custom function. Move this to using the firmware_feature_table. Signed-off-by: Michael Neuling cc: Vaidyanathan Srinivasan cc: Linux PPC dev Signed-off-by: Benjamin Herrenschmidt

cpu: convert 'cpu' and 'machinecheck' sysdev_class to a regular subsystem

2011-12-21T22:29:42Z

This moves the 'cpu sysdev_class' over to a regular 'cpu' subsystem and converts the devices to regular devices. The sysdev drivers are implemented as subsystem interfaces now. After all sysdev classes are ported to regular driver core entities, the sysdev implementation will be entirely removed from the kernel. Userspace relies on events and generic sysfs subsystem infrastructure from sysdev devices, which are made available with this conversion. Cc: Haavard Skinnemoen Cc: Hans-Christian Egtvedt Cc: Tony Luck Cc: Fenghua Yu Cc: Arnd Bergmann Cc: Benjamin Herrenschmidt Cc: Paul Mackerras Cc: Martin Schwidefsky Cc: Heiko Carstens Cc: Paul Mundt Cc: "David S. Miller" Cc: Chris Metcalf Cc: Thomas Gleixner Cc: Ingo Molnar Cc: "H. Peter Anvin" Cc: Borislav Petkov Cc: Tigran Aivazian Cc: Len Brown Cc: Zhang Rui Cc: Dave Jones Cc: Peter Zijlstra Cc: Russell King Cc: Andrew Morton Cc: Arjan van de Ven Cc: "Rafael J. Wysocki" Cc: "Srivatsa S. Bhat" Signed-off-by: Kay Sievers Signed-off-by: Greg Kroah-Hartman

powerpc: Add support for new hcall H_BEST_ENERGY

2010-11-29T04:48:19Z

Create sysfs interface to export data from H_BEST_ENERGY hcall that can be used by administrative tools on supported pseries platforms for energy management optimizations. sys/device/system/cpu/pseries_(de)activate_hint_list and sys/device/system/cpu/cpuN/pseries_(de)activate_hint will provide hints for activation and deactivation of cpus respectively. These hints are abstract number given by the hypervisor based on the extended knowledge the hypervisor has regarding the system topology and resource mappings. The activate and the deactivate sysfs entry is for the two distinct operations that we could do for energy savings. When we have more capacity than required, we could deactivate few core to save energy. The choice of the core to deactivate will be based on /sys/devices/system/cpu/deactivate_hint_list. The comma separated list of cpus (cores) will be the preferred choice. If we have to activate some of the deactivated cores, then /sys/devices/system/cpu/activate_hint_list will be used. The per-cpu file /sys/device/system/cpu/cpuN/pseries_(de)activate_hint further provide more fine grain information by exporting the value of the hint itself. Added new driver module arch/powerpc/platforms/pseries/pseries_energy.c under new config option CONFIG_PSERIES_ENERGY Signed-off-by: Vaidyanathan Srinivasan Signed-off-by: Benjamin Herrenschmidt