On Fri, 30 Nov 2018 17:11:04 +0100 Paul Kocialkowski <[email protected]> wrote:
> In order to test whether the load tracker is working as expected, we > need the ability to compare the commit result with the underrun > indication. With the load tracker always enabled, commits that are > expected to trigger an underrun are always rejected, so userspace > cannot get the actual underrun indication from the hardware. > > Add a debugfs entry to disable/enable the load tracker, so that a DRM > commit expected to trigger an underrun can go through with the load > tracker disabled. The underrun indication is then available to > userspace and can be checked against the commit result with the load > tracker enabled. > > Signed-off-by: Paul Kocialkowski <[email protected]> > --- > > Changes since v1: > * Moved all the debugfs-related functions and structure to vc4_debugfs.c. > > drivers/gpu/drm/vc4/vc4_debugfs.c | 58 +++++++++++++++++++++++++++++++ > drivers/gpu/drm/vc4/vc4_drv.c | 2 ++ > drivers/gpu/drm/vc4/vc4_drv.h | 2 ++ > drivers/gpu/drm/vc4/vc4_kms.c | 6 +++- > 4 files changed, 67 insertions(+), 1 deletion(-) > > diff --git a/drivers/gpu/drm/vc4/vc4_debugfs.c > b/drivers/gpu/drm/vc4/vc4_debugfs.c > index 7a0003de71ab..8f4d7fadb226 100644 > --- a/drivers/gpu/drm/vc4/vc4_debugfs.c > +++ b/drivers/gpu/drm/vc4/vc4_debugfs.c > @@ -32,9 +32,67 @@ static const struct drm_info_list vc4_debugfs_list[] = { > > #define VC4_DEBUGFS_ENTRIES ARRAY_SIZE(vc4_debugfs_list) > > +static int vc4_debugfs_load_tracker_get(struct seq_file *m, void *data) > +{ > + struct drm_device *dev = m->private; > + struct vc4_dev *vc4 = to_vc4_dev(dev); > + > + if (vc4->load_tracker_enabled) > + seq_printf(m, "enabled\n"); > + else > + seq_printf(m, "disabled\n"); > + > + return 0; > +} > + > +static ssize_t vc4_debugfs_load_tracker_set(struct file *file, > + const char __user *ubuf, > + size_t len, loff_t *offp) > +{ > + struct seq_file *m = file->private_data; > + struct drm_device *dev = m->private; > + struct vc4_dev *vc4 = to_vc4_dev(dev); > + char buf[32] = {}; > + > + if (len >= sizeof(buf)) > + return -EINVAL; > + > + if (copy_from_user(buf, ubuf, len)) > + return -EFAULT; > + > + if (!strncasecmp(buf, "enable", 6)) > + vc4->load_tracker_enabled = true; > + else if (!strncasecmp(buf, "disable", 7)) > + vc4->load_tracker_enabled = false; > + else > + return -EINVAL; > + > + return len; > +} > + > +static int vc4_debugfs_load_tracker_open(struct inode *inode, struct file > *file) > +{ > + return single_open(file, vc4_debugfs_load_tracker_get, > inode->i_private); > +} > + > +static const struct file_operations vc4_debugfs_load_tracker_fops = { > + .owner = THIS_MODULE, > + .open = vc4_debugfs_load_tracker_open, > + .read = seq_read, > + .write = vc4_debugfs_load_tracker_set, > +}; > + > int > vc4_debugfs_init(struct drm_minor *minor) > { > + struct dentry *dentry; > + > + dentry = debugfs_create_file("load_tracker", S_IRUGO | S_IWUSR, > + minor->debugfs_root, minor->dev, > + &vc4_debugfs_load_tracker_fops); > + if (!dentry) > + return -ENOMEM; Hm, maybe you could use debugfs_create_bool() instead of re-implementing it. The values won't be enabled/disabled though (IIRC, it's Y or N). > + > return drm_debugfs_create_files(vc4_debugfs_list, VC4_DEBUGFS_ENTRIES, > minor->debugfs_root, minor); > } > diff --git a/drivers/gpu/drm/vc4/vc4_drv.c b/drivers/gpu/drm/vc4/vc4_drv.c > index 7195a0bcceb3..12ac971d24d6 100644 > --- a/drivers/gpu/drm/vc4/vc4_drv.c > +++ b/drivers/gpu/drm/vc4/vc4_drv.c > @@ -290,6 +290,8 @@ static int vc4_drm_bind(struct device *dev) > > drm_fbdev_generic_setup(drm, 32); > > + vc4->load_tracker_enabled = true; > + > return 0; > > unbind_all: > diff --git a/drivers/gpu/drm/vc4/vc4_drv.h b/drivers/gpu/drm/vc4/vc4_drv.h > index 11369da944b6..8d0f2f16a9e8 100644 > --- a/drivers/gpu/drm/vc4/vc4_drv.h > +++ b/drivers/gpu/drm/vc4/vc4_drv.h > @@ -188,6 +188,8 @@ struct vc4_dev { > > int power_refcount; > > + bool load_tracker_enabled; > + > /* Mutex controlling the power refcount. */ > struct mutex power_lock; > > diff --git a/drivers/gpu/drm/vc4/vc4_kms.c b/drivers/gpu/drm/vc4/vc4_kms.c > index b905a19c1470..4b2509b1b8ed 100644 > --- a/drivers/gpu/drm/vc4/vc4_kms.c > +++ b/drivers/gpu/drm/vc4/vc4_kms.c > @@ -473,6 +473,7 @@ static const struct drm_private_state_funcs > vc4_load_tracker_state_funcs = { > static int > vc4_atomic_check(struct drm_device *dev, struct drm_atomic_state *state) > { > + struct vc4_dev *vc4 = to_vc4_dev(dev); > int ret; > > ret = vc4_ctm_atomic_check(dev, state); > @@ -483,7 +484,10 @@ vc4_atomic_check(struct drm_device *dev, struct > drm_atomic_state *state) > if (ret) > return ret; > > - return vc4_load_tracker_atomic_check(state); > + if (vc4->load_tracker_enabled) > + return vc4_load_tracker_atomic_check(state); > + > + return 0; > } > > static const struct drm_mode_config_funcs vc4_mode_funcs = { _______________________________________________ dri-devel mailing list [email protected] https://lists.freedesktop.org/mailman/listinfo/dri-devel
