From b12f3ea7c1884c0c79e516ed9ffee7c7058a61c3 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Adri=C3=A1n=20Larumbe?= Date: Wed, 6 Mar 2024 01:56:36 +0000 Subject: [PATCH] drm/panfrost: Replace fdinfo's profiling debugfs knob with sysfs MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Debugfs isn't always available in production builds that try to squeeze every single byte out of the kernel image, but we still need a way to toggle the timestamp and cycle counter registers so that jobs can be profiled for fdinfo's drm engine and cycle calculations. Drop the debugfs knob and replace it with a sysfs file that accomplishes the same functionality, and document its ABI in a separate file. Signed-off-by: Adrián Larumbe Reviewed-by: Boris Brezillon Reviewed-by: Steven Price Signed-off-by: Boris Brezillon Link: https://patchwork.freedesktop.org/patch/msgid/20240306015819.822128-2-adrian.larumbe@collabora.com --- .../testing/sysfs-driver-panfrost-profiling | 10 +++++ Documentation/gpu/panfrost.rst | 9 +++++ drivers/gpu/drm/panfrost/Makefile | 2 - drivers/gpu/drm/panfrost/panfrost_debugfs.c | 21 ---------- drivers/gpu/drm/panfrost/panfrost_debugfs.h | 14 ------- drivers/gpu/drm/panfrost/panfrost_device.h | 2 +- drivers/gpu/drm/panfrost/panfrost_drv.c | 40 ++++++++++++++++--- drivers/gpu/drm/panfrost/panfrost_job.c | 2 +- 8 files changed, 56 insertions(+), 44 deletions(-) create mode 100644 Documentation/ABI/testing/sysfs-driver-panfrost-profiling delete mode 100644 drivers/gpu/drm/panfrost/panfrost_debugfs.c delete mode 100644 drivers/gpu/drm/panfrost/panfrost_debugfs.h diff --git a/Documentation/ABI/testing/sysfs-driver-panfrost-profiling b/Documentation/ABI/testing/sysfs-driver-panfrost-profiling new file mode 100644 index 000000000000..1d8bb0978920 --- /dev/null +++ b/Documentation/ABI/testing/sysfs-driver-panfrost-profiling @@ -0,0 +1,10 @@ +What: /sys/bus/platform/drivers/panfrost/.../profiling +Date: February 2024 +KernelVersion: 6.8.0 +Contact: Adrian Larumbe +Description: + Get/set drm fdinfo's engine and cycles profiling status. + Valid values are: + 0: Don't enable fdinfo job profiling sources. + 1: Enable fdinfo job profiling sources, this enables both the GPU's + timestamp and cycle counter registers. \ No newline at end of file diff --git a/Documentation/gpu/panfrost.rst b/Documentation/gpu/panfrost.rst index b80e41f4b2c5..51ba375fd80d 100644 --- a/Documentation/gpu/panfrost.rst +++ b/Documentation/gpu/panfrost.rst @@ -38,3 +38,12 @@ the currently possible format options: Possible `drm-engine-` key names are: `fragment`, and `vertex-tiler`. `drm-curfreq-` values convey the current operating frequency for that engine. + +Users must bear in mind that engine and cycle sampling are disabled by default, +because of power saving concerns. `fdinfo` users and benchmark applications which +query the fdinfo file must make sure to toggle the job profiling status of the +driver by writing into the appropriate sysfs node:: + + echo > /sys/bus/platform/drivers/panfrost/[a-f0-9]*.gpu/profiling + +Where `N` is either `0` or `1`, depending on the desired enablement status. diff --git a/drivers/gpu/drm/panfrost/Makefile b/drivers/gpu/drm/panfrost/Makefile index 2c01c1e7523e..7da2b3f02ed9 100644 --- a/drivers/gpu/drm/panfrost/Makefile +++ b/drivers/gpu/drm/panfrost/Makefile @@ -12,6 +12,4 @@ panfrost-y := \ panfrost_perfcnt.o \ panfrost_dump.o -panfrost-$(CONFIG_DEBUG_FS) += panfrost_debugfs.o - obj-$(CONFIG_DRM_PANFROST) += panfrost.o diff --git a/drivers/gpu/drm/panfrost/panfrost_debugfs.c b/drivers/gpu/drm/panfrost/panfrost_debugfs.c deleted file mode 100644 index 72d4286a6bf7..000000000000 --- a/drivers/gpu/drm/panfrost/panfrost_debugfs.c +++ /dev/null @@ -1,21 +0,0 @@ -// SPDX-License-Identifier: GPL-2.0 -/* Copyright 2023 Collabora ltd. */ -/* Copyright 2023 Amazon.com, Inc. or its affiliates. */ - -#include -#include -#include -#include -#include - -#include "panfrost_device.h" -#include "panfrost_gpu.h" -#include "panfrost_debugfs.h" - -void panfrost_debugfs_init(struct drm_minor *minor) -{ - struct drm_device *dev = minor->dev; - struct panfrost_device *pfdev = platform_get_drvdata(to_platform_device(dev->dev)); - - debugfs_create_atomic_t("profile", 0600, minor->debugfs_root, &pfdev->profile_mode); -} diff --git a/drivers/gpu/drm/panfrost/panfrost_debugfs.h b/drivers/gpu/drm/panfrost/panfrost_debugfs.h deleted file mode 100644 index c5af5f35877f..000000000000 --- a/drivers/gpu/drm/panfrost/panfrost_debugfs.h +++ /dev/null @@ -1,14 +0,0 @@ -/* SPDX-License-Identifier: GPL-2.0 */ -/* - * Copyright 2023 Collabora ltd. - * Copyright 2023 Amazon.com, Inc. or its affiliates. - */ - -#ifndef PANFROST_DEBUGFS_H -#define PANFROST_DEBUGFS_H - -#ifdef CONFIG_DEBUG_FS -void panfrost_debugfs_init(struct drm_minor *minor); -#endif - -#endif /* PANFROST_DEBUGFS_H */ diff --git a/drivers/gpu/drm/panfrost/panfrost_device.h b/drivers/gpu/drm/panfrost/panfrost_device.h index 62f7e3527385..cffcb0ac7c11 100644 --- a/drivers/gpu/drm/panfrost/panfrost_device.h +++ b/drivers/gpu/drm/panfrost/panfrost_device.h @@ -130,7 +130,7 @@ struct panfrost_device { struct list_head scheduled_jobs; struct panfrost_perfcnt *perfcnt; - atomic_t profile_mode; + bool profile_mode; struct mutex sched_lock; diff --git a/drivers/gpu/drm/panfrost/panfrost_drv.c b/drivers/gpu/drm/panfrost/panfrost_drv.c index a926d71e8131..eec250114114 100644 --- a/drivers/gpu/drm/panfrost/panfrost_drv.c +++ b/drivers/gpu/drm/panfrost/panfrost_drv.c @@ -20,7 +20,6 @@ #include "panfrost_job.h" #include "panfrost_gpu.h" #include "panfrost_perfcnt.h" -#include "panfrost_debugfs.h" static bool unstable_ioctls; module_param_unsafe(unstable_ioctls, bool, 0600); @@ -600,10 +599,6 @@ static const struct drm_driver panfrost_drm_driver = { .gem_create_object = panfrost_gem_create_object, .gem_prime_import_sg_table = panfrost_gem_prime_import_sg_table, - -#ifdef CONFIG_DEBUG_FS - .debugfs_init = panfrost_debugfs_init, -#endif }; static int panfrost_probe(struct platform_device *pdev) @@ -692,6 +687,40 @@ static void panfrost_remove(struct platform_device *pdev) drm_dev_put(ddev); } +static ssize_t profiling_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct panfrost_device *pfdev = dev_get_drvdata(dev); + + return sysfs_emit(buf, "%d\n", pfdev->profile_mode); +} + +static ssize_t profiling_store(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t len) +{ + struct panfrost_device *pfdev = dev_get_drvdata(dev); + bool value; + int err; + + err = kstrtobool(buf, &value); + if (err) + return err; + + pfdev->profile_mode = value; + + return len; +} + +static DEVICE_ATTR_RW(profiling); + +static struct attribute *panfrost_attrs[] = { + &dev_attr_profiling.attr, + NULL, +}; + +ATTRIBUTE_GROUPS(panfrost); + /* * The OPP core wants the supply names to be NULL terminated, but we need the * correct num_supplies value for regulator core. Hence, we NULL terminate here @@ -789,6 +818,7 @@ static struct platform_driver panfrost_driver = { .name = "panfrost", .pm = pm_ptr(&panfrost_pm_ops), .of_match_table = dt_match, + .dev_groups = panfrost_groups, }, }; module_platform_driver(panfrost_driver); diff --git a/drivers/gpu/drm/panfrost/panfrost_job.c b/drivers/gpu/drm/panfrost/panfrost_job.c index 0c2dbf6ef2a5..a61ef0af9a4e 100644 --- a/drivers/gpu/drm/panfrost/panfrost_job.c +++ b/drivers/gpu/drm/panfrost/panfrost_job.c @@ -243,7 +243,7 @@ static void panfrost_job_hw_submit(struct panfrost_job *job, int js) subslot = panfrost_enqueue_job(pfdev, js, job); /* Don't queue the job if a reset is in progress */ if (!atomic_read(&pfdev->reset.pending)) { - if (atomic_read(&pfdev->profile_mode)) { + if (pfdev->profile_mode) { panfrost_cycle_counter_get(pfdev); job->is_profiled = true; job->start_time = ktime_get();