Re: [Freedreno] [PATCH 11/11] drm/msm/dpu: rip out debugfs support from dpu_plane

[abhinavk@codeaurora.org]

On 2021-09-30 07:00, Dmitry Baryshkov wrote:
> In preparations of virtualizing the dpu_plane rip out debugfs support
> from dpu_plane (as it is mostly used to expose plane's pipe registers).
> Also move disable_danger file to danger/ debugfs subdir where it 
> belongs.
> 
> Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>

I am yet to review the second part of the virtual plane series to 
understand why this removal
is necessary so I might be missing something.

The plane's debugfs holds useful information to check a few things 
rightaway.

So if there is some misconfiguration or corruption in addition to the 
plane state,
this is good to check.

localhost /sys/kernel/debug/dri/1/plane35 # cat src_blk
[4000] 03000556 00000000 00000000 03000556
[4010] 00000000 00414000 00000000 0040e000
[4020] 00000000 00001600 00000080 00000000
[4030] 800236ff 03010002 80000001 00000000
[4040] 00000000 00000030 000c0087 00000707
[4050] 00000000 00000000 00000000 00000000
[4060] 0000ffff 00000000 00000000 00000001
[4070] 00000000 44556677 00112233 00000000
[4080] 00000000 00000000 00000000 00000000
[4090] 00000000 00000000 00000000 00000000
[40a0] 00000000 00414000 00000000 0040e000
[40b0] 00000000 00000000 00000000 00000000
[40c0] 00000000 00000000 00000000 00000000
[40d0] 0003f820 00000000 00000000 00000000
[40e0] 0003e2c4 00000000 00000000 00000000
[40f0] 000f000f 00010330 02e402e4 00000000
[4100] 00000000 00000000 03000556 00000000
[4110] 00000000 00000000 03000556 00000000
[4120] 00000000 00000000 03000556 00000000
[4130] 00000000 0000000f 00000000 0000000f
[4140] 00000000 00000000 00000000 00000000

So I would like to keep this functionality unless there is some 
compelling reason
to remove this.

BTW, are you going to submit the second half as a new series now that 
most
of the first one has been reviewed?

> ---
>  drivers/gpu/drm/msm/disp/dpu1/dpu_kms.c   | 123 ++++++++--------
>  drivers/gpu/drm/msm/disp/dpu1/dpu_kms.h   |  69 ---------
>  drivers/gpu/drm/msm/disp/dpu1/dpu_plane.c | 171 +---------------------
>  drivers/gpu/drm/msm/disp/dpu1/dpu_plane.h |   6 +
>  4 files changed, 69 insertions(+), 300 deletions(-)
> 
> diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_kms.c
> b/drivers/gpu/drm/msm/disp/dpu1/dpu_kms.c
> index ae48f41821cf..fe33273cdf57 100644
> --- a/drivers/gpu/drm/msm/disp/dpu1/dpu_kms.c
> +++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_kms.c
> @@ -101,84 +101,85 @@ static int dpu_debugfs_safe_stats_show(struct
> seq_file *s, void *v)
>  }
>  DEFINE_SHOW_ATTRIBUTE(dpu_debugfs_safe_stats);
> 
> -static void dpu_debugfs_danger_init(struct dpu_kms *dpu_kms,
> -		struct dentry *parent)
> +static ssize_t _dpu_plane_danger_read(struct file *file,
> +			char __user *buff, size_t count, loff_t *ppos)
>  {
> -	struct dentry *entry = debugfs_create_dir("danger", parent);
> +	struct dpu_kms *kms = file->private_data;
> +	int len;
> +	char buf[40];
> 
> -	debugfs_create_file("danger_status", 0600, entry,
> -			dpu_kms, &dpu_debugfs_danger_stats_fops);
> -	debugfs_create_file("safe_status", 0600, entry,
> -			dpu_kms, &dpu_debugfs_safe_stats_fops);
> +	len = scnprintf(buf, sizeof(buf), "%d\n", !kms->has_danger_ctrl);
> +
> +	return simple_read_from_buffer(buff, count, ppos, buf, len);
>  }
> 
> -static int _dpu_debugfs_show_regset32(struct seq_file *s, void *data)
> +static void _dpu_plane_set_danger_state(struct dpu_kms *kms, bool 
> enable)
>  {
> -	struct dpu_debugfs_regset32 *regset = s->private;
> -	struct dpu_kms *dpu_kms = regset->dpu_kms;
> -	void __iomem *base;
> -	uint32_t i, addr;
> -
> -	if (!dpu_kms->mmio)
> -		return 0;
> -
> -	base = dpu_kms->mmio + regset->offset;
> -
> -	/* insert padding spaces, if needed */
> -	if (regset->offset & 0xF) {
> -		seq_printf(s, "[%x]", regset->offset & ~0xF);
> -		for (i = 0; i < (regset->offset & 0xF); i += 4)
> -			seq_puts(s, "         ");
> -	}
> -
> -	pm_runtime_get_sync(&dpu_kms->pdev->dev);
> -
> -	/* main register output */
> -	for (i = 0; i < regset->blk_len; i += 4) {
> -		addr = regset->offset + i;
> -		if ((addr & 0xF) == 0x0)
> -			seq_printf(s, i ? "\n[%x]" : "[%x]", addr);
> -		seq_printf(s, " %08x", readl_relaxed(base + i));
> +	struct drm_plane *plane;
> +
> +	drm_for_each_plane(plane, kms->dev) {
> +		if (plane->fb && plane->state) {
> +			dpu_plane_danger_signal_ctrl(plane, enable);
> +			DPU_DEBUG("plane:%d img:%dx%d ",
> +				plane->base.id, plane->fb->width,
> +				plane->fb->height);
> +			DPU_DEBUG("src[%d,%d,%d,%d] dst[%d,%d,%d,%d]\n",
> +				plane->state->src_x >> 16,
> +				plane->state->src_y >> 16,
> +				plane->state->src_w >> 16,
> +				plane->state->src_h >> 16,
> +				plane->state->crtc_x, plane->state->crtc_y,
> +				plane->state->crtc_w, plane->state->crtc_h);
> +		} else {
> +			DPU_DEBUG("Inactive plane:%d\n", plane->base.id);
> +		}
>  	}
> -	seq_puts(s, "\n");
> -	pm_runtime_put_sync(&dpu_kms->pdev->dev);
> -
> -	return 0;
>  }
> 
> -static int dpu_debugfs_open_regset32(struct inode *inode,
> -		struct file *file)
> +static ssize_t _dpu_plane_danger_write(struct file *file,
> +		    const char __user *user_buf, size_t count, loff_t *ppos)
>  {
> -	return single_open(file, _dpu_debugfs_show_regset32, 
> inode->i_private);
> -}
> +	struct dpu_kms *kms = file->private_data;
> +	int disable_panic;
> +	int ret;
> 
> -static const struct file_operations dpu_fops_regset32 = {
> -	.open =		dpu_debugfs_open_regset32,
> -	.read =		seq_read,
> -	.llseek =	seq_lseek,
> -	.release =	single_release,
> -};
> +	ret = kstrtouint_from_user(user_buf, count, 0, &disable_panic);
> +	if (ret)
> +		return ret;
> 
> -void dpu_debugfs_setup_regset32(struct dpu_debugfs_regset32 *regset,
> -		uint32_t offset, uint32_t length, struct dpu_kms *dpu_kms)
> -{
> -	if (regset) {
> -		regset->offset = offset;
> -		regset->blk_len = length;
> -		regset->dpu_kms = dpu_kms;
> +	if (disable_panic) {
> +		/* Disable panic signal for all active pipes */
> +		DPU_DEBUG("Disabling danger:\n");
> +		_dpu_plane_set_danger_state(kms, false);
> +		kms->has_danger_ctrl = false;
> +	} else {
> +		/* Enable panic signal for all active pipes */
> +		DPU_DEBUG("Enabling danger:\n");
> +		kms->has_danger_ctrl = true;
> +		_dpu_plane_set_danger_state(kms, true);
>  	}
> +
> +	return count;
>  }
> 
> -void dpu_debugfs_create_regset32(const char *name, umode_t mode,
> -		void *parent, struct dpu_debugfs_regset32 *regset)
> +static const struct file_operations dpu_plane_danger_enable = {
> +	.open = simple_open,
> +	.read = _dpu_plane_danger_read,
> +	.write = _dpu_plane_danger_write,
> +};
> +
> +static void dpu_debugfs_danger_init(struct dpu_kms *dpu_kms,
> +		struct dentry *parent)
>  {
> -	if (!name || !regset || !regset->dpu_kms || !regset->blk_len)
> -		return;
> +	struct dentry *entry = debugfs_create_dir("danger", parent);
> 
> -	/* make sure offset is a multiple of 4 */
> -	regset->offset = round_down(regset->offset, 4);
> +	debugfs_create_file("danger_status", 0600, entry,
> +			dpu_kms, &dpu_debugfs_danger_stats_fops);
> +	debugfs_create_file("safe_status", 0600, entry,
> +			dpu_kms, &dpu_debugfs_safe_stats_fops);
> +	debugfs_create_file("disable_danger", 0600, entry,
> +			dpu_kms, &dpu_plane_danger_enable);
> 
> -	debugfs_create_file(name, mode, parent, regset, &dpu_fops_regset32);
>  }
> 
>  static int dpu_kms_debugfs_init(struct msm_kms *kms, struct drm_minor 
> *minor)
> diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_kms.h
> b/drivers/gpu/drm/msm/disp/dpu1/dpu_kms.h
> index 323a6bce9e64..ab65c817eb42 100644
> --- a/drivers/gpu/drm/msm/disp/dpu1/dpu_kms.h
> +++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_kms.h
> @@ -166,75 +166,6 @@ struct dpu_global_state
>  struct dpu_global_state
>  	*__must_check dpu_kms_get_global_state(struct drm_atomic_state *s);
> 
> -/**
> - * Debugfs functions - extra helper functions for debugfs support
> - *
> - * Main debugfs documentation is located at,
> - *
> - * Documentation/filesystems/debugfs.rst
> - *
> - * @dpu_debugfs_setup_regset32: Initialize data for 
> dpu_debugfs_create_regset32
> - * @dpu_debugfs_create_regset32: Create 32-bit register dump file
> - * @dpu_debugfs_get_root: Get root dentry for DPU_KMS's debugfs node
> - */
> -
> -/**
> - * Companion structure for dpu_debugfs_create_regset32. Do not 
> initialize the
> - * members of this structure explicitly; use
> dpu_debugfs_setup_regset32 instead.
> - */
> -struct dpu_debugfs_regset32 {
> -	uint32_t offset;
> -	uint32_t blk_len;
> -	struct dpu_kms *dpu_kms;
> -};
> -
> -/**
> - * dpu_debugfs_setup_regset32 - Initialize register block definition
> for debugfs
> - * This function is meant to initialize dpu_debugfs_regset32 
> structures for use
> - * with dpu_debugfs_create_regset32.
> - * @regset: opaque register definition structure
> - * @offset: sub-block offset
> - * @length: sub-block length, in bytes
> - * @dpu_kms: pointer to dpu kms structure
> - */
> -void dpu_debugfs_setup_regset32(struct dpu_debugfs_regset32 *regset,
> -		uint32_t offset, uint32_t length, struct dpu_kms *dpu_kms);
> -
> -/**
> - * dpu_debugfs_create_regset32 - Create register read back file for 
> debugfs
> - *
> - * This function is almost identical to the standard 
> debugfs_create_regset32()
> - * function, with the main difference being that a list of register
> - * names/offsets do not need to be provided. The 'read' function 
> simply outputs
> - * sequential register values over a specified range.
> - *
> - * Similar to the related debugfs_create_regset32 API, the structure 
> pointed to
> - * by regset needs to persist for the lifetime of the created file. 
> The calling
> - * code is responsible for initialization/management of this 
> structure.
> - *
> - * The structure pointed to by regset is meant to be opaque. Please 
> use
> - * dpu_debugfs_setup_regset32 to initialize it.
> - *
> - * @name:   File name within debugfs
> - * @mode:   File mode within debugfs
> - * @parent: Parent directory entry within debugfs, can be NULL
> - * @regset: Pointer to persistent register block definition
> - */
> -void dpu_debugfs_create_regset32(const char *name, umode_t mode,
> -		void *parent, struct dpu_debugfs_regset32 *regset);
> -
> -/**
> - * dpu_debugfs_get_root - Return root directory entry for KMS's 
> debugfs
> - *
> - * The return value should be passed as the 'parent' argument to 
> subsequent
> - * debugfs create calls.
> - *
> - * @dpu_kms: Pointer to DPU's KMS structure
> - *
> - * Return: dentry pointer for DPU's debugfs location
> - */
> -void *dpu_debugfs_get_root(struct dpu_kms *dpu_kms);
> -
>  /**
>   * DPU info management functions
>   * These functions/definitions allow for building up a 'dpu_info' 
> structure
> diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_plane.c
> b/drivers/gpu/drm/msm/disp/dpu1/dpu_plane.c
> index d8018e664925..42bcde1ddd0f 100644
> --- a/drivers/gpu/drm/msm/disp/dpu1/dpu_plane.c
> +++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_plane.c
> @@ -108,13 +108,6 @@ struct dpu_plane {
>  	bool is_virtual;
>  	struct list_head mplane_list;
>  	struct dpu_mdss_cfg *catalog;
> -
> -	/* debugfs related stuff */
> -	struct dentry *debugfs_root;
> -	struct dpu_debugfs_regset32 debugfs_src;
> -	struct dpu_debugfs_regset32 debugfs_scaler;
> -	struct dpu_debugfs_regset32 debugfs_csc;
> -	bool debugfs_default_scale;
>  };
> 
>  static const uint64_t supported_format_modifiers[] = {
> @@ -1343,7 +1336,7 @@ static void dpu_plane_reset(struct drm_plane 
> *plane)
>  }
> 
>  #ifdef CONFIG_DEBUG_FS
> -static void dpu_plane_danger_signal_ctrl(struct drm_plane *plane, bool 
> enable)
> +void dpu_plane_danger_signal_ctrl(struct drm_plane *plane, bool 
> enable)
>  {
>  	struct dpu_plane *pdpu = to_dpu_plane(plane);
>  	struct dpu_kms *dpu_kms = _dpu_plane_get_kms(plane);
> @@ -1355,168 +1348,8 @@ static void
> dpu_plane_danger_signal_ctrl(struct drm_plane *plane, bool enable)
>  	_dpu_plane_set_qos_ctrl(plane, enable, DPU_PLANE_QOS_PANIC_CTRL);
>  	pm_runtime_put_sync(&dpu_kms->pdev->dev);
>  }
> -
> -static ssize_t _dpu_plane_danger_read(struct file *file,
> -			char __user *buff, size_t count, loff_t *ppos)
> -{
> -	struct dpu_kms *kms = file->private_data;
> -	int len;
> -	char buf[40];
> -
> -	len = scnprintf(buf, sizeof(buf), "%d\n", !kms->has_danger_ctrl);
> -
> -	return simple_read_from_buffer(buff, count, ppos, buf, len);
> -}
> -
> -static void _dpu_plane_set_danger_state(struct dpu_kms *kms, bool 
> enable)
> -{
> -	struct drm_plane *plane;
> -
> -	drm_for_each_plane(plane, kms->dev) {
> -		if (plane->fb && plane->state) {
> -			dpu_plane_danger_signal_ctrl(plane, enable);
> -			DPU_DEBUG("plane:%d img:%dx%d ",
> -				plane->base.id, plane->fb->width,
> -				plane->fb->height);
> -			DPU_DEBUG("src[%d,%d,%d,%d] dst[%d,%d,%d,%d]\n",
> -				plane->state->src_x >> 16,
> -				plane->state->src_y >> 16,
> -				plane->state->src_w >> 16,
> -				plane->state->src_h >> 16,
> -				plane->state->crtc_x, plane->state->crtc_y,
> -				plane->state->crtc_w, plane->state->crtc_h);
> -		} else {
> -			DPU_DEBUG("Inactive plane:%d\n", plane->base.id);
> -		}
> -	}
> -}
> -
> -static ssize_t _dpu_plane_danger_write(struct file *file,
> -		    const char __user *user_buf, size_t count, loff_t *ppos)
> -{
> -	struct dpu_kms *kms = file->private_data;
> -	int disable_panic;
> -	int ret;
> -
> -	ret = kstrtouint_from_user(user_buf, count, 0, &disable_panic);
> -	if (ret)
> -		return ret;
> -
> -	if (disable_panic) {
> -		/* Disable panic signal for all active pipes */
> -		DPU_DEBUG("Disabling danger:\n");
> -		_dpu_plane_set_danger_state(kms, false);
> -		kms->has_danger_ctrl = false;
> -	} else {
> -		/* Enable panic signal for all active pipes */
> -		DPU_DEBUG("Enabling danger:\n");
> -		kms->has_danger_ctrl = true;
> -		_dpu_plane_set_danger_state(kms, true);
> -	}
> -
> -	return count;
> -}
> -
> -static const struct file_operations dpu_plane_danger_enable = {
> -	.open = simple_open,
> -	.read = _dpu_plane_danger_read,
> -	.write = _dpu_plane_danger_write,
> -};
> -
> -static int _dpu_plane_init_debugfs(struct drm_plane *plane)
> -{
> -	struct dpu_plane *pdpu = to_dpu_plane(plane);
> -	struct dpu_kms *kms = _dpu_plane_get_kms(plane);
> -	const struct dpu_sspp_cfg *cfg = pdpu->pipe_hw->cap;
> -	const struct dpu_sspp_sub_blks *sblk = cfg->sblk;
> -
> -	/* create overall sub-directory for the pipe */
> -	pdpu->debugfs_root =
> -		debugfs_create_dir(plane->name,
> -				plane->dev->primary->debugfs_root);
> -
> -	/* don't error check these */
> -	debugfs_create_xul("features", 0600,
> -			pdpu->debugfs_root, (unsigned long 
> *)&pdpu->pipe_hw->cap->features);
> -
> -	/* add register dump support */
> -	dpu_debugfs_setup_regset32(&pdpu->debugfs_src,
> -			sblk->src_blk.base + cfg->base,
> -			sblk->src_blk.len,
> -			kms);
> -	dpu_debugfs_create_regset32("src_blk", 0400,
> -			pdpu->debugfs_root, &pdpu->debugfs_src);
> -
> -	if (cfg->features & BIT(DPU_SSPP_SCALER_QSEED3) ||
> -			cfg->features & BIT(DPU_SSPP_SCALER_QSEED3LITE) ||
> -			cfg->features & BIT(DPU_SSPP_SCALER_QSEED2) ||
> -			cfg->features & BIT(DPU_SSPP_SCALER_QSEED4)) {
> -		dpu_debugfs_setup_regset32(&pdpu->debugfs_scaler,
> -				sblk->scaler_blk.base + cfg->base,
> -				sblk->scaler_blk.len,
> -				kms);
> -		dpu_debugfs_create_regset32("scaler_blk", 0400,
> -				pdpu->debugfs_root,
> -				&pdpu->debugfs_scaler);
> -		debugfs_create_bool("default_scaling",
> -				0600,
> -				pdpu->debugfs_root,
> -				&pdpu->debugfs_default_scale);
> -	}
> -
> -	if (cfg->features & BIT(DPU_SSPP_CSC) ||
> -			cfg->features & BIT(DPU_SSPP_CSC_10BIT)) {
> -		dpu_debugfs_setup_regset32(&pdpu->debugfs_csc,
> -				sblk->csc_blk.base + cfg->base,
> -				sblk->csc_blk.len,
> -				kms);
> -		dpu_debugfs_create_regset32("csc_blk", 0400,
> -				pdpu->debugfs_root, &pdpu->debugfs_csc);
> -	}
> -
> -	debugfs_create_u32("xin_id",
> -			0400,
> -			pdpu->debugfs_root,
> -			(u32 *) &cfg->xin_id);
> -	debugfs_create_u32("clk_ctrl",
> -			0400,
> -			pdpu->debugfs_root,
> -			(u32 *) &cfg->clk_ctrl);
> -	debugfs_create_x32("creq_vblank",
> -			0600,
> -			pdpu->debugfs_root,
> -			(u32 *) &sblk->creq_vblank);
> -	debugfs_create_x32("danger_vblank",
> -			0600,
> -			pdpu->debugfs_root,
> -			(u32 *) &sblk->danger_vblank);
> -
> -	debugfs_create_file("disable_danger",
> -			0600,
> -			pdpu->debugfs_root,
> -			kms, &dpu_plane_danger_enable);
> -
> -	return 0;
> -}
> -#else
> -static int _dpu_plane_init_debugfs(struct drm_plane *plane)
> -{
> -	return 0;
> -}
>  #endif
> 
> -static int dpu_plane_late_register(struct drm_plane *plane)
> -{
> -	return _dpu_plane_init_debugfs(plane);
> -}
> -
> -static void dpu_plane_early_unregister(struct drm_plane *plane)
> -{
> -	struct dpu_plane *pdpu = to_dpu_plane(plane);
> -
> -	debugfs_remove_recursive(pdpu->debugfs_root);
> -}
> -
>  static bool dpu_plane_format_mod_supported(struct drm_plane *plane,
>  		uint32_t format, uint64_t modifier)
>  {
> @@ -1541,8 +1374,6 @@ static const struct drm_plane_funcs 
> dpu_plane_funcs = {
>  		.reset = dpu_plane_reset,
>  		.atomic_duplicate_state = dpu_plane_duplicate_state,
>  		.atomic_destroy_state = dpu_plane_destroy_state,
> -		.late_register = dpu_plane_late_register,
> -		.early_unregister = dpu_plane_early_unregister,
>  		.format_mod_supported = dpu_plane_format_mod_supported,
>  };
> 
> diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_plane.h
> b/drivers/gpu/drm/msm/disp/dpu1/dpu_plane.h
> index 1ee5ca5fcdf7..9d51dad5c6a5 100644
> --- a/drivers/gpu/drm/msm/disp/dpu1/dpu_plane.h
> +++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_plane.h
> @@ -126,4 +126,10 @@ void dpu_plane_clear_multirect(const struct
> drm_plane_state *drm_state);
>  int dpu_plane_color_fill(struct drm_plane *plane,
>  		uint32_t color, uint32_t alpha);
> 
> +#ifdef CONFIG_DEBUG_FS
> +void dpu_plane_danger_signal_ctrl(struct drm_plane *plane, bool 
> enable);
> +#else
> +static inline void dpu_plane_danger_signal_ctrl(struct drm_plane
> *plane, bool enable) {}
> +#endif
> +
>  #endif /* _DPU_PLANE_H_ */