Re: [PATCH v4 3/3] drm/ingenic: Add option to alloc cached GEM buffers

Hi

Am 15.05.21 um 16:53 schrieb Paul Cercueil:

Alloc GEM buffers backed by noncoherent memory on SoCs where it is actually faster than write-combine.

This dramatically speeds up software rendering on these SoCs, even for tasks where write-combine memory should in theory be faster (e.g. simple blits).

v3: The option is now selected per-SoC instead of being a module parameter.

Signed-off-by: Paul Cercueil paul@crapouillou.net

drivers/gpu/drm/ingenic/ingenic-drm-drv.c | 56 ++++++++++++++++++++++- drivers/gpu/drm/ingenic/ingenic-ipu.c | 18 ++++++-- 2 files changed, 68 insertions(+), 6 deletions(-)

diff --git a/drivers/gpu/drm/ingenic/ingenic-drm-drv.c b/drivers/gpu/drm/ingenic/ingenic-drm-drv.c index 09225b770bb8..5f64e8583eec 100644 --- a/drivers/gpu/drm/ingenic/ingenic-drm-drv.c +++ b/drivers/gpu/drm/ingenic/ingenic-drm-drv.c @@ -9,6 +9,7 @@ #include <linux/component.h> #include <linux/clk.h> #include <linux/dma-mapping.h> +#include <linux/io.h> #include <linux/module.h> #include <linux/mutex.h> #include <linux/of_device.h> @@ -23,6 +24,7 @@ #include <drm/drm_color_mgmt.h> #include <drm/drm_crtc.h> #include <drm/drm_crtc_helper.h> +#include <drm/drm_damage_helper.h> #include <drm/drm_drv.h> #include <drm/drm_encoder.h> #include <drm/drm_gem_cma_helper.h> @@ -57,6 +59,7 @@ struct ingenic_dma_hwdescs { struct jz_soc_info { bool needs_dev_clk; bool has_osd;

• bool map_noncoherent; unsigned int max_width, max_height; const u32 *formats_f0, *formats_f1; unsigned int num_formats_f0, num_formats_f1;

@@ -410,6 +413,8 @@ static int ingenic_drm_plane_atomic_check(struct drm_plane *plane, old_plane_state->fb->format->format != new_plane_state->fb->format->format)) crtc_state->mode_changed = true;

• drm_atomic_helper_check_plane_damage(state, new_plane_state);
• return 0; }

@@ -544,8 +549,8 @@ static void ingenic_drm_plane_atomic_update(struct drm_plane *plane, struct drm_atomic_state *state) { struct ingenic_drm *priv = drm_device_get_priv(plane->dev);

• struct drm_plane_state *newstate = drm_atomic_get_new_plane_state(state,

• 							  plane);
  

• struct drm_plane_state *newstate = drm_atomic_get_new_plane_state(state, plane);
• struct drm_plane_state *oldstate = drm_atomic_get_old_plane_state(state, plane); struct drm_crtc_state *crtc_state; struct ingenic_dma_hwdesc *hwdesc; unsigned int width, height, cpp, offset;

@@ -553,6 +558,8 @@ static void ingenic_drm_plane_atomic_update(struct drm_plane *plane, u32 fourcc;

if (newstate && newstate->fb) {

• drm_gem_cma_sync_data(&priv->drm, oldstate, newstate);
  

• crtc_state = newstate->crtc->state;

  addr = drm_fb_cma_get_gem_addr(newstate->fb, newstate, 0);

@@ -742,6 +749,43 @@ static void ingenic_drm_disable_vblank(struct drm_crtc *crtc) regmap_update_bits(priv->map, JZ_REG_LCD_CTRL, JZ_LCD_CTRL_EOF_IRQ, 0); }

+static int ingenic_drm_atomic_helper_dirtyfb(struct drm_framebuffer *fb,

• 			     struct drm_file *file_priv,
  

• 			     unsigned int flags,
  

• 			     unsigned int color,
  

• 			     struct drm_clip_rect *clips,
  

• 			     unsigned int num_clips)
  

+{

• struct ingenic_drm *priv = drm_device_get_priv(fb->dev);
• if (!priv->soc_info->map_noncoherent)

• return 0;
  

I'm not sure you can get away without calling drm_atomic_helper_dirtyfb(). The function does some things with the plane's damage-clips property. If you don't call it here, the plane might pile up unhandled clipping areas. It's better to call it and rely on the test in drm_gem_cma_sync_data(). See below on how to optimize this.

• return drm_atomic_helper_dirtyfb(fb, file_priv, flags,

• 			 color, clips, num_clips);
  

+}

+static const struct drm_framebuffer_funcs ingenic_drm_gem_fb_funcs =

{

• .destroy = drm_gem_fb_destroy,
• .create_handle = drm_gem_fb_create_handle,
• .dirty = ingenic_drm_atomic_helper_dirtyfb,

+};

You don't seem to be using this anywhere. You have to implement a custom fb_create for drm_mode_config_funcs. [1]

BUT: I think the overall approach should be to only use this on SoCs with non-coherency setting. Use drm_gem_fb_create() on systems without non-coherency and use drm_gem_fb_create_with_dirty() on systems with non-coherency (i.e., have two instances of drm_mode_config_funcs). Only call drm_plane_enable_fb_damage_clips() on systems with non-coherency.

+static struct drm_gem_object * +ingenic_drm_gem_create_object(struct drm_device *drm, size_t size) +{

• struct ingenic_drm *priv = drm_device_get_priv(drm);
• struct drm_gem_cma_object *obj;
• obj = kzalloc(sizeof(*obj), GFP_KERNEL);
• if (!obj)

• return ERR_PTR(-ENOMEM);
  

• obj->map_noncoherent = priv->soc_info->map_noncoherent;
• return &obj->base;

+}

• DEFINE_DRM_GEM_CMA_FOPS(ingenic_drm_fops);

  static const struct drm_driver ingenic_drm_driver_data = {

@@ -754,6 +798,7 @@ static const struct drm_driver ingenic_drm_driver_data = { .patchlevel = 0,

.fops = &ingenic_drm_fops,

• .gem_create_object = ingenic_drm_gem_create_object, DRM_GEM_CMA_DRIVER_OPS,

  .irq_handler = ingenic_drm_irq_handler,

@@ -961,6 +1006,8 @@ static int ingenic_drm_bind(struct device *dev, bool has_components) return ret; }

• drm_plane_enable_fb_damage_clips(&priv->f1);

• drm_crtc_helper_add(&priv->crtc, &ingenic_drm_crtc_helper_funcs);

  ret = drm_crtc_init_with_planes(drm, &priv->crtc, primary,

@@ -989,6 +1036,8 @@ static int ingenic_drm_bind(struct device *dev, bool has_components) return ret; }

• drm_plane_enable_fb_damage_clips(&priv->f0);
  

• if (IS_ENABLED(CONFIG_DRM_INGENIC_IPU) && has_components) { ret = component_bind_all(dev, drm); if (ret) {

@@ -1245,6 +1294,7 @@ static const u32 jz4770_formats_f0[] = { static const struct jz_soc_info jz4740_soc_info = { .needs_dev_clk = true, .has_osd = false,

• .map_noncoherent = false, .max_width = 800, .max_height = 600, .formats_f1 = jz4740_formats,

@@ -1255,6 +1305,7 @@ static const struct jz_soc_info jz4740_soc_info =

{

static const struct jz_soc_info jz4725b_soc_info = { .needs_dev_clk = false, .has_osd = true,

• .map_noncoherent = false, .max_width = 800, .max_height = 600, .formats_f1 = jz4725b_formats_f1,

@@ -1266,6 +1317,7 @@ static const struct jz_soc_info jz4725b_soc_info = { static const struct jz_soc_info jz4770_soc_info = { .needs_dev_clk = false, .has_osd = true,

• .map_noncoherent = true, .max_width = 1280, .max_height = 720, .formats_f1 = jz4770_formats_f1,

diff --git a/drivers/gpu/drm/ingenic/ingenic-ipu.c b/drivers/gpu/drm/ingenic/ingenic-ipu.c index 3b1091e7c0cd..a4d1b500c3ad 100644 --- a/drivers/gpu/drm/ingenic/ingenic-ipu.c +++ b/drivers/gpu/drm/ingenic/ingenic-ipu.c @@ -20,10 +20,13 @@

#include <drm/drm_atomic.h> #include <drm/drm_atomic_helper.h> +#include <drm/drm_damage_helper.h> #include <drm/drm_drv.h> #include <drm/drm_fb_cma_helper.h> #include <drm/drm_fourcc.h> #include <drm/drm_gem_atomic_helper.h> +#include <drm/drm_gem_cma_helper.h> +#include <drm/drm_gem_framebuffer_helper.h> #include <drm/drm_plane.h> #include <drm/drm_plane_helper.h> #include <drm/drm_property.h> @@ -285,8 +288,8 @@ static void ingenic_ipu_plane_atomic_update(struct drm_plane *plane, struct drm_atomic_state *state) { struct ingenic_ipu *ipu = plane_to_ingenic_ipu(plane);

• struct drm_plane_state *newstate = drm_atomic_get_new_plane_state(state,

• 							  plane);
  

• struct drm_plane_state *newstate = drm_atomic_get_new_plane_state(state, plane);
• struct drm_plane_state *oldstate = drm_atomic_get_new_plane_state(state, plane);

get_old_state ?

const struct drm_format_info *finfo; u32 ctrl, stride = 0, coef_index = 0, format = 0; bool needs_modeset, upscaling_w, upscaling_h; @@ -317,6 +320,8 @@ static void ingenic_ipu_plane_atomic_update(struct drm_plane *plane, JZ_IPU_CTRL_CHIP_EN | JZ_IPU_CTRL_LCDC_SEL); }

• drm_gem_cma_sync_data(ipu->drm, oldstate, newstate);

If you want to optimize, maybe put this line behind

if (priv->soc_info->map_noncoherent)

/* New addresses will be committed in vblank handler... */ ipu->addr_y = drm_fb_cma_get_gem_addr(newstate->fb, newstate, 0); if (finfo->num_planes > 1) @@ -541,7 +546,7 @@ static int ingenic_ipu_plane_atomic_check(struct drm_plane *plane,

if (!new_plane_state->crtc || !crtc_state->mode.hdisplay || !crtc_state->mode.vdisplay)

• return 0;
  

• goto out_check_damage;
  
  

  /* Plane must be fully visible */ if (new_plane_state->crtc_x < 0 || new_plane_state->crtc_y < 0 ||

@@ -558,7 +563,7 @@ static int ingenic_ipu_plane_atomic_check(struct drm_plane *plane, return -EINVAL;

if (!osd_changed(new_plane_state, old_plane_state))

• return 0;
  

• goto out_check_damage;
  
  

  crtc_state->mode_changed = true;

@@ -592,6 +597,9 @@ static int ingenic_ipu_plane_atomic_check(struct drm_plane *plane, ipu->denom_w = denom_w; ipu->denom_h = denom_h;

+out_check_damage:

• drm_atomic_helper_check_plane_damage(state, new_plane_state);

If you implement my suggestion above, this line could also be behind

if (priv->soc_info->map_noncoherent)

Best regards

Thomas

[1] https://elixir.bootlin.com/linux/v5.13-rc1/source/drivers/gpu/drm/ingenic/in...