Re: [PATCH] drm: hdlcd: Replace the mode config's atomic_commit with the proper implementation.

On Tue, May 31, 2016 at 12:03:04PM +0100, Liviu Dudau wrote:

The HDLCD atomic_commit code was mis-using the drm_atomic_helper_commit() function to implement the non-blocking code. Replace that with the correct implementation that does the async queue-ing of commits.

Signed-off-by: Liviu Dudau Liviu.Dudau@arm.com

Please don't roll your own atomic nonblocking commit any more, but instead use the generic one I'm working on:

https://cgit.freedesktop.org/~danvet/drm/log/

Review and testing very much appreciated (the patches are on the m-l, too).

Cheers, Daniel

---

drivers/gpu/drm/arm/hdlcd_crtc.c | 64 +++++++++++++++++++--------- drivers/gpu/drm/arm/hdlcd_drv.c | 90 ++++++++++++++++++++++++++++------------ drivers/gpu/drm/arm/hdlcd_drv.h | 3 +- 3 files changed, 109 insertions(+), 48 deletions(-)

diff --git a/drivers/gpu/drm/arm/hdlcd_crtc.c b/drivers/gpu/drm/arm/hdlcd_crtc.c index d1e8d31..523890d 100644 --- a/drivers/gpu/drm/arm/hdlcd_crtc.c +++ b/drivers/gpu/drm/arm/hdlcd_crtc.c @@ -106,7 +106,7 @@ static void hdlcd_crtc_mode_set_nofb(struct drm_crtc *crtc) struct hdlcd_drm_private *hdlcd = crtc_to_hdlcd_priv(crtc); struct drm_display_mode *m = &crtc->state->adjusted_mode; struct videomode vm;

• unsigned int polarities, line_length, err;

• unsigned int polarities, err;

  vm.vfront_porch = m->crtc_vsync_start - m->crtc_vdisplay; vm.vback_porch = m->crtc_vtotal - m->crtc_vsync_end;

@@ -122,23 +122,18 @@ static void hdlcd_crtc_mode_set_nofb(struct drm_crtc *crtc) if (m->flags & DRM_MODE_FLAG_PVSYNC) polarities |= HDLCD_POLARITY_VSYNC;

• line_length = crtc->primary->state->fb->pitches[0];

• /* Allow max number of outstanding requests and largest burst size */ hdlcd_write(hdlcd, HDLCD_REG_BUS_OPTIONS, HDLCD_BUS_MAX_OUTSTAND | HDLCD_BUS_BURST_16);

• hdlcd_write(hdlcd, HDLCD_REG_FB_LINE_LENGTH, line_length);

• hdlcd_write(hdlcd, HDLCD_REG_FB_LINE_PITCH, line_length);

• hdlcd_write(hdlcd, HDLCD_REG_FB_LINE_COUNT, m->crtc_vdisplay - 1); hdlcd_write(hdlcd, HDLCD_REG_V_DATA, m->crtc_vdisplay - 1); hdlcd_write(hdlcd, HDLCD_REG_V_BACK_PORCH, vm.vback_porch - 1); hdlcd_write(hdlcd, HDLCD_REG_V_FRONT_PORCH, vm.vfront_porch - 1); hdlcd_write(hdlcd, HDLCD_REG_V_SYNC, vm.vsync_len - 1);

• hdlcd_write(hdlcd, HDLCD_REG_H_DATA, m->crtc_hdisplay - 1); hdlcd_write(hdlcd, HDLCD_REG_H_BACK_PORCH, vm.hback_porch - 1); hdlcd_write(hdlcd, HDLCD_REG_H_FRONT_PORCH, vm.hfront_porch - 1); hdlcd_write(hdlcd, HDLCD_REG_H_SYNC, vm.hsync_len - 1);

• hdlcd_write(hdlcd, HDLCD_REG_H_DATA, m->crtc_hdisplay - 1); hdlcd_write(hdlcd, HDLCD_REG_POLARITIES, polarities);

  err = hdlcd_set_pxl_fmt(crtc);

@@ -153,20 +148,19 @@ static void hdlcd_crtc_enable(struct drm_crtc *crtc) struct hdlcd_drm_private *hdlcd = crtc_to_hdlcd_priv(crtc);

clk_prepare_enable(hdlcd->clk);

• hdlcd_crtc_mode_set_nofb(crtc); hdlcd_write(hdlcd, HDLCD_REG_COMMAND, 1);

• drm_crtc_vblank_on(crtc);

}

static void hdlcd_crtc_disable(struct drm_crtc *crtc) { struct hdlcd_drm_private *hdlcd = crtc_to_hdlcd_priv(crtc);

• if (!crtc->primary->fb)

• if (!crtc->state->active) return;

  hdlcd_write(hdlcd, HDLCD_REG_COMMAND, 0); clk_disable_unprepare(hdlcd->clk);

• drm_crtc_vblank_off(crtc);

}

static int hdlcd_crtc_atomic_check(struct drm_crtc *crtc, @@ -208,6 +202,21 @@ static void hdlcd_crtc_atomic_begin(struct drm_crtc *crtc, static void hdlcd_crtc_atomic_flush(struct drm_crtc *crtc, struct drm_crtc_state *state) {

• struct hdlcd_drm_private *hdlcd = crtc_to_hdlcd_priv(crtc);
• struct drm_device *drm = crtc->dev;
• unsigned long flags;
• struct drm_pending_vblank_event *e;
• spin_lock_irqsave(&drm->event_lock, flags);
• e = list_first_entry_or_null(&hdlcd->event_list, typeof(*e), base.link);
• if (e) {

• list_del(&e->base.link);
  

• drm_crtc_send_vblank_event(&hdlcd->crtc, e);
  

• drm_crtc_vblank_put(&hdlcd->crtc);
  

• }
• spin_unlock_irqrestore(&drm->event_lock, flags);

}

static bool hdlcd_crtc_mode_fixup(struct drm_crtc *crtc, @@ -219,13 +228,8 @@ static bool hdlcd_crtc_mode_fixup(struct drm_crtc *crtc,

static const struct drm_crtc_helper_funcs hdlcd_crtc_helper_funcs = { .mode_fixup = hdlcd_crtc_mode_fixup,

• .mode_set = drm_helper_crtc_mode_set,
• .mode_set_base = drm_helper_crtc_mode_set_base,
• .mode_set_nofb = hdlcd_crtc_mode_set_nofb, .enable = hdlcd_crtc_enable, .disable = hdlcd_crtc_disable,
• .prepare = hdlcd_crtc_disable,
• .commit = hdlcd_crtc_enable, .atomic_check = hdlcd_crtc_atomic_check, .atomic_begin = hdlcd_crtc_atomic_begin, .atomic_flush = hdlcd_crtc_atomic_flush,

@@ -234,6 +238,15 @@ static const struct drm_crtc_helper_funcs hdlcd_crtc_helper_funcs = { static int hdlcd_plane_atomic_check(struct drm_plane *plane, struct drm_plane_state *state) {

• u32 src_w, src_h;
• src_w = state->src_w >> 16;
• src_h = state->src_h >> 16;
• /* we can't do any scaling of the plane source */
• if ((src_w != state->crtc_w) || (src_h != state->crtc_h))

• return -EINVAL;
  

• return 0;

}

@@ -242,20 +255,31 @@ static void hdlcd_plane_atomic_update(struct drm_plane *plane, { struct hdlcd_drm_private *hdlcd; struct drm_gem_cma_object *gem;

• unsigned int depth, bpp;
• u32 src_w, src_h, dest_w, dest_h; dma_addr_t scanout_start;

• if (!plane->state->crtc || !plane->state->fb)

• if (!plane->state->fb) return;

• hdlcd = crtc_to_hdlcd_priv(plane->state->crtc);

• drm_fb_get_bpp_depth(plane->state->fb->pixel_format, &depth, &bpp);
• src_w = plane->state->src_w >> 16;
• src_h = plane->state->src_h >> 16;
• dest_w = plane->state->crtc_w;
• dest_h = plane->state->crtc_h; gem = drm_fb_cma_get_gem_obj(plane->state->fb, 0);

• scanout_start = gem->paddr;

• scanout_start = gem->paddr + plane->state->fb->offsets[0] +

• plane->state->crtc_y * plane->state->fb->pitches[0] +
  

• plane->state->crtc_x * bpp / 8;
  

• hdlcd = plane->dev->dev_private;
• hdlcd_write(hdlcd, HDLCD_REG_FB_LINE_LENGTH, plane->state->fb->pitches[0]);
• hdlcd_write(hdlcd, HDLCD_REG_FB_LINE_PITCH, plane->state->fb->pitches[0]);
• hdlcd_write(hdlcd, HDLCD_REG_FB_LINE_COUNT, dest_h - 1); hdlcd_write(hdlcd, HDLCD_REG_FB_BASE, scanout_start);

}

static const struct drm_plane_helper_funcs hdlcd_plane_helper_funcs = {

• .prepare_fb = NULL,
• .cleanup_fb = NULL, .atomic_check = hdlcd_plane_atomic_check, .atomic_update = hdlcd_plane_atomic_update,

}; diff --git a/drivers/gpu/drm/arm/hdlcd_drv.c b/drivers/gpu/drm/arm/hdlcd_drv.c index 21b1427..4585aa3 100644 --- a/drivers/gpu/drm/arm/hdlcd_drv.c +++ b/drivers/gpu/drm/arm/hdlcd_drv.c @@ -14,11 +14,14 @@ #include <linux/clk.h> #include <linux/component.h> #include <linux/list.h> +#include <linux/mutex.h> #include <linux/of_graph.h> #include <linux/of_reserved_mem.h> #include <linux/pm_runtime.h> +#include <linux/wait.h>

#include <drm/drmP.h> +#include <drm/drm_atomic.h> #include <drm/drm_atomic_helper.h> #include <drm/drm_crtc.h> #include <drm/drm_crtc_helper.h> @@ -108,10 +111,60 @@ static void hdlcd_fb_output_poll_changed(struct drm_device *drm) drm_fbdev_cma_hotplug_event(hdlcd->fbdev); }

+static void hdlcd_atomic_complete(struct drm_device *dev,

• 		  struct drm_atomic_state *state)
  

+{

• /* ToDo: Wait for fences */
• drm_atomic_helper_commit_modeset_disables(dev, state);
• drm_atomic_helper_commit_planes(dev, state, false);
• drm_atomic_helper_commit_modeset_enables(dev, state);
• drm_atomic_helper_wait_for_vblanks(dev, state);
• drm_atomic_helper_cleanup_planes(dev, state);
• drm_atomic_state_free(state);

+}

+static void hdlcd_atomic_work(struct work_struct *work) +{

• struct hdlcd_drm_private *hdlcd;
• hdlcd = container_of(work, struct hdlcd_drm_private, work);
• hdlcd_atomic_complete(hdlcd->crtc.dev, hdlcd->state);

+}

static int hdlcd_atomic_commit(struct drm_device *dev, struct drm_atomic_state *state, bool nonblock) {

• return drm_atomic_helper_commit(dev, state, false);

• struct hdlcd_drm_private *hdlcd = dev->dev_private;
• int err = drm_atomic_helper_prepare_planes(dev, state);
• if (err)

• return err;
  

• if (nonblock && !list_empty(&hdlcd->work.entry)) {

• /* pending commit found, bail out */
  

• return -EBUSY;
  

• }
• mutex_lock(&hdlcd->work_lock);
• flush_work(&hdlcd->work);
• /*

• * This is the point of non return, where software commits to
  

• * handle the new state
  

• */
  

• drm_atomic_helper_swap_state(dev, state);
• hdlcd->state = state;
• if (nonblock)

• schedule_work(&hdlcd->work);
  

• else

• hdlcd_atomic_complete(dev, state);
  

• mutex_unlock(&hdlcd->work_lock);
• return 0;

}

static const struct drm_mode_config_funcs hdlcd_mode_config_funcs = { @@ -160,24 +213,9 @@ static irqreturn_t hdlcd_irq(int irq, void *arg) atomic_inc(&hdlcd->vsync_count);

#endif

• if (irq_status & HDLCD_INTERRUPT_VSYNC) {

• bool events_sent = false;
  

• unsigned long flags;
  

• struct drm_pending_vblank_event	*e, *t;
  

• if (irq_status & HDLCD_INTERRUPT_VSYNC) drm_crtc_handle_vblank(&hdlcd->crtc);

• spin_lock_irqsave(&drm->event_lock, flags);
  

• list_for_each_entry_safe(e, t, &hdlcd->event_list, base.link) {
  

• 	list_del(&e->base.link);
  

• 	drm_crtc_send_vblank_event(&hdlcd->crtc, e);
  

• 	events_sent = true;
  

• }
  

• if (events_sent)
  

• 	drm_crtc_vblank_put(&hdlcd->crtc);
  

• spin_unlock_irqrestore(&drm->event_lock, flags);
  

• }
• /* acknowledge interrupt(s) */ hdlcd_write(hdlcd, HDLCD_REG_INT_CLEAR, irq_status);

@@ -200,9 +238,13 @@ static int hdlcd_irq_postinstall(struct drm_device *drm)

/* enable debug interrupts */ irq_mask |= HDLCD_DEBUG_INT_MASK; +#endif

• /* enable vsync interrupts */

• irq_mask |= HDLCD_INTERRUPT_VSYNC;

  hdlcd_write(hdlcd, HDLCD_REG_INT_MASK, irq_mask);

-#endif

• return 0;

}

@@ -225,20 +267,11 @@ static void hdlcd_irq_uninstall(struct drm_device *drm)

static int hdlcd_enable_vblank(struct drm_device *drm, unsigned int crtc) {

• struct hdlcd_drm_private *hdlcd = drm->dev_private;
• unsigned int mask = hdlcd_read(hdlcd, HDLCD_REG_INT_MASK);
• hdlcd_write(hdlcd, HDLCD_REG_INT_MASK, mask | HDLCD_INTERRUPT_VSYNC);
• return 0;

}

static void hdlcd_disable_vblank(struct drm_device *drm, unsigned int crtc) {

• struct hdlcd_drm_private *hdlcd = drm->dev_private;
• unsigned int mask = hdlcd_read(hdlcd, HDLCD_REG_INT_MASK);
• hdlcd_write(hdlcd, HDLCD_REG_INT_MASK, mask & ~HDLCD_INTERRUPT_VSYNC);

}

#ifdef CONFIG_DEBUG_FS @@ -271,6 +304,7 @@ static int hdlcd_show_pxlclock(struct seq_file *m, void *arg) static struct drm_info_list hdlcd_debugfs_list[] = { { "interrupt_count", hdlcd_show_underrun_count, 0 }, { "clocks", hdlcd_show_pxlclock, 0 },

• { "fb", drm_fb_cma_debugfs_show, 0 },

};

static int hdlcd_debugfs_init(struct drm_minor *minor) @@ -354,6 +388,8 @@ static int hdlcd_drm_bind(struct device *dev)

drm->dev_private = hdlcd; dev_set_drvdata(dev, drm);

• mutex_init(&hdlcd->work_lock);

• INIT_WORK(&hdlcd->work, hdlcd_atomic_work);

  hdlcd_setup_mode_config(drm); ret = hdlcd_load(drm, 0);

diff --git a/drivers/gpu/drm/arm/hdlcd_drv.h b/drivers/gpu/drm/arm/hdlcd_drv.h index e7cea82..92822e9 100644 --- a/drivers/gpu/drm/arm/hdlcd_drv.h +++ b/drivers/gpu/drm/arm/hdlcd_drv.h @@ -9,11 +9,12 @@ struct hdlcd_drm_private { void __iomem *mmio; struct clk *clk; struct drm_fbdev_cma *fbdev;

• struct drm_framebuffer *fb; struct list_head event_list; struct drm_crtc crtc; struct drm_plane *plane; struct drm_atomic_state *state;

• struct work_struct work;
• struct mutex work_lock;

#ifdef CONFIG_DEBUG_FS atomic_t buffer_underrun_count; atomic_t bus_error_count; -- 2.8.2

---

dri-devel mailing list dri-devel@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/dri-devel