Re: [PATCH v5 01/18] drm/rockchip: vop2: Add debugfs support

Heiko Stübner
2024-12-10T11:57:55Z

Hi Andy,

Am Montag, 9. Dezember 2024, 13:29:13 CET schrieb Andy Yan:
> From: Andy Yan <andy.yan@rock-chips.com>
>
> /sys/kernel/debug/dri/vop2/summary: dump vop display state
> /sys/kernel/debug/dri/vop2/regs: dump whole vop registers
> /sys/kernel/debug/dri/vop2/active_regs: only dump the registers of
> activated modules
>
> Reviewed-by: Sascha Hauer <s.hauer@pengutronix.de>
> Signed-off-by: Andy Yan <andy.yan@rock-chips.com>
> Tested-by: Michael Riesch <michael.riesch@wolfvision.net> # on RK3568
> Tested-by: Detlev Casanova <detlev.casanova@collabora.com>
> ---

> +static void __vop2_regs_dump(struct seq_file *s, bool active_only)
> +{
> + struct drm_info_node *node = s->private;
> + struct vop2 *vop2 = node->info_ent->data;
> + struct drm_minor *minor = node->minor;
> + struct drm_device *drm_dev = minor->dev;
> + const struct vop2_regs_dump *dump;
> + unsigned int i;
> +
> + drm_modeset_lock_all(drm_dev);
> +
> + regcache_drop_region(vop2->map, 0, vop2_regmap_config.max_register);
> +
> + if (vop2->enable_count) {
> + for (i = 0; i < vop2->data->regs_dump_size; i++) {
> + dump = &vop2->data->regs_dump[i];
> + vop2_regs_print(vop2, s, dump, active_only);
> + }
> + } else {
> + seq_printf(s, "VOP disabled\n");
> + }
> + drm_modeset_unlock_all(drm_dev);
> +

nit: not needed empty line at the end of the function

> +}
> +

> +static void vop2_debugfs_init(struct vop2 *vop2, struct drm_minor *minor)
> +{
> + struct dentry *root;
> + unsigned int i;
> +
> + root = debugfs_create_dir("vop2", minor->debugfs_root);
> + if (!IS_ERR(root)) {
> + for (i = 0; i < ARRAY_SIZE(vop2_debugfs_list); i++)
> + vop2_debugfs_list[i].data = vop2;
> +
> + drm_debugfs_create_files(vop2_debugfs_list,
> + ARRAY_SIZE(vop2_debugfs_list),
> + root, minor);
> + }
> +}
> +
> +static int vop2_crtc_late_register(struct drm_crtc *crtc)
> +{
> + struct vop2_video_port *vp = to_vop2_video_port(crtc);
> + struct vop2 *vop2 = vp->vop2;
> +
> + if (drm_crtc_index(crtc) == 0)
> + vop2_debugfs_init(vop2, crtc->dev->primary);
> +
> + return 0;
> +}

I'm wondering about, shoudln't there be an unregister step too?
I.e. the late_register callback says:
"should be unregistered in the early_unregister callback" [0].

And there exists drm_debugfs_remove_files(), though it doesn't
seem t be used much - just by tegra.

I haven't managed to find drm code handling that automatically though?

Heiko

[0] https://elixir.bootlin.com/linux/v6.12.4/source/include/drm/drm_crtc.h#L737
[1] https://elixir.bootlin.com/linux/v6.12.4/source/drivers/gpu/drm/drm_debugfs.c#L265