MLK-16536-12 video: fbdev: dcss: flush cfifo once per frame

Change the cfifo flush to be once per frame to combine
possible multiple flush requests in one frame into one
flush to improve performance. And during one frame, only
flush requests from different channels can be combined,
and the different requests from the same channel cannot
be combined into one flush.

Signed-off-by: Fancy Fang <chen.fang@nxp.com>
Reviewed-by: Robby Cai <robby.cai@nxp.com>

diff --git a/drivers/video/fbdev/mxc/imx_dcss.c b/drivers/video/fbdev/mxc/imx_dcss.c
index 7add7bc..3ef2d74 100644 (file)
--- a/drivers/video/fbdev/mxc/imx_dcss.c
+++ b/drivers/video/fbdev/mxc/imx_dcss.c
@@ -251,6 +251,7 @@ struct vsync_info {
 
 struct ctxld_commit {
        struct list_head list;
+       atomic_t refcount;
        struct work_struct work;
        void *data;
        uint32_t sb_data_len;
@@ -293,6 +294,7 @@ struct dcss_channel_info {
        int blank;                      /* see FB_BLANK_* macros */
        uint32_t csc_mode;              /* see CSC_MODE_* macros */
        bool dpr_scaler_en;             /* record dpr and scaler enabled or not */
+       unsigned long update_stamp;     /* default is ~0x0UL */
 
        void *dev_data;                 /* pointer to dcss_info */
 };
@@ -523,6 +525,8 @@ static int dcss_pan_display(struct fb_var_screeninfo *var,
                            struct fb_info *fbi);
 static int dcss_ioctl(struct fb_info *fbi, unsigned int cmd,
                      unsigned long arg);
+static int vcount_compare(unsigned long vcount,
+                         struct vsync_info *vinfo);
 
 static struct fb_ops dcss_ops = {
        .owner = THIS_MODULE,
@@ -852,6 +856,7 @@ static int fill_one_chan_info(uint32_t chan_id,
        info->channel_id = chan_id;
        info->channel_en = (chan_id == 0) ? 1 : 0;
        info->blank = FB_BLANK_NORMAL;
+       info->update_stamp = ~0x0UL;
 
        switch (chan_id) {
        case 0:
@@ -2302,8 +2307,8 @@ static void copy_data_to_cfifo(struct ctxld_fifo *cfifo,
                        count = kfifo_out(&cfifo->fifo, cb->sb_addr, count);
                        WARN_ON(1);
                }
-               cc->sb_hp_data_len = count;
-               cc->sb_data_len = count;
+               cc->sb_hp_data_len += count;
+               cc->sb_data_len += count;
        }
 
        if (cb->db_data_len) {
@@ -2314,7 +2319,7 @@ static void copy_data_to_cfifo(struct ctxld_fifo *cfifo,
                        count = kfifo_out(&cfifo->fifo, cb->db_addr, count);
                        WARN_ON(1);
                }
-               cc->db_data_len = count;
+               cc->db_data_len += count;
        }
 }
 
@@ -2329,10 +2334,75 @@ static struct ctxld_commit *alloc_cc(struct dcss_info *info)
        INIT_LIST_HEAD(&cc->list);
        INIT_WORK(&cc->work, dcss_ctxld_config);
        cc->data = info;
+       atomic_set(&cc->refcount, 0);
+
+       return cc;
+}
+
+static struct ctxld_commit *obtain_cc(int ch_id, struct dcss_info *info)
+{
+       int ret;
+       unsigned long irqflags;
+       struct dcss_channel_info *cinfo;
+       struct ctxld_commit *cc = NULL;
+       struct platform_device *pdev = info->pdev;
+       struct dcss_channels *chans = &info->chans;
+       struct ctxld_fifo *cfifo = &info->cfifo;
+       struct vsync_info *vinfo = &info->vinfo;
+
+       cinfo = &chans->chan_info[ch_id];
+
+       /* wait for next frame window */
+       ret = wait_event_interruptible_timeout(vinfo->vwait,
+                       vcount_compare(cinfo->update_stamp, vinfo),
+                       HZ);
+       if (!ret) {
+               dev_err(&pdev->dev, "wait next frame timeout\n");
+               return ERR_PTR(-EBUSY);
+       }
+
+       spin_lock_irqsave(&vinfo->vwait.lock, irqflags);
+
+       cinfo->update_stamp = vinfo->vcount;
+       if (!list_empty(&cfifo->ctxld_list)) {
+               cc = list_first_entry(&cfifo->ctxld_list,
+                                     struct ctxld_commit,
+                                     list);
+               atomic_inc(&cc->refcount);
+       }
+
+       spin_unlock_irqrestore(&vinfo->vwait.lock, irqflags);
+
+       if (!cc) {
+               cc = alloc_cc(info);
+               if (IS_ERR(cc))
+                       return cc;
+
+               spin_lock_irqsave(&vinfo->vwait.lock, irqflags);
+
+               if (list_empty(&cfifo->ctxld_list))
+                       list_add_tail(&cfifo->ctxld_list, &cc->list);
+               else {
+                       kfree(cc);
+                       cc = list_first_entry(&cfifo->ctxld_list,
+                                             struct ctxld_commit,
+                                             list);
+               }
+               atomic_inc(&cc->refcount);
+
+               spin_unlock_irqrestore(&vinfo->vwait.lock, irqflags);
+       }
 
        return cc;
 }
 
+static void release_cc(struct ctxld_commit *cc)
+{
+       WARN_ON(!atomic_read(&cc->refcount));
+
+       atomic_dec(&cc->refcount);
+}
+
 static void flush_cfifo(struct ctxld_fifo *cfifo,
                        struct work_struct *work)
 {
@@ -2343,6 +2413,24 @@ static void flush_cfifo(struct ctxld_fifo *cfifo,
        WARN(!ret, "work has already been queued\n");
 }
 
+static int defer_flush_cfifo(struct ctxld_fifo *cfifo)
+{
+       int i;
+       struct dcss_info *info;
+       struct dcss_channels *chans;
+       struct dcss_channel_info *cinfo;
+
+       info = container_of(cfifo, struct dcss_info, cfifo);
+       chans = &info->chans;
+
+       for (i = 0; i < 3; i++) {
+               cinfo = &chans->chan_info[i];
+               cinfo->update_stamp = info->vinfo.vcount;
+       }
+
+       return 0;
+}
+
 static int finish_cfifo(struct ctxld_fifo *cfifo)
 {
        flush_workqueue(cfifo->ctxld_wq);
@@ -2631,7 +2719,7 @@ static int dcss_set_par(struct fb_info *fbi)
                goto fail;
 
 #if USE_CTXLD
-       cc = alloc_cc(info);
+       cc = obtain_cc(fb_node, info);
        if (IS_ERR(cc)) {
                ret = PTR_ERR(cc);
                goto fail;
@@ -2639,7 +2727,7 @@ static int dcss_set_par(struct fb_info *fbi)
 
        commit_cfifo(fb_node, info, cc);
 
-       flush_cfifo(&info->cfifo, &cc->work);
+       release_cc(cc);
 #endif
 
        goto out;
@@ -2712,7 +2800,7 @@ static int dcss_blank(int blank, struct fb_info *fbi)
        dcss_channel_blank(blank, cinfo);
 
 #if USE_CTXLD
-       cc = alloc_cc(info);
+       cc = obtain_cc(fb_node, info);
        if (IS_ERR(cc)) {
                ret = PTR_ERR(cc);
                goto fail;
@@ -2720,7 +2808,7 @@ static int dcss_blank(int blank, struct fb_info *fbi)
 
        commit_cfifo(fb_node, info, cc);
 
-       flush_cfifo(&info->cfifo, &cc->work);
+       release_cc(cc);
 #endif
 
        cinfo->blank = blank;
@@ -2742,6 +2830,7 @@ static int dcss_pan_display(struct fb_var_screeninfo *var,
                            struct fb_info *fbi)
 {
        int ret = 0;
+       int fb_node = fbi->node;
        uint32_t offset, pitch, luma_addr, chroma_addr = 0;
        struct dcss_channel_info *cinfo = fbi->par;
        struct dcss_info *info = cinfo->dev_data;
@@ -2778,7 +2867,8 @@ static int dcss_pan_display(struct fb_var_screeninfo *var,
                        chroma_addr + (offset >> 1));
        }
 
-       cc = alloc_cc(info);
+#if USE_CTXLD
+       cc = obtain_cc(fb_node, info);
        if (IS_ERR(cc)) {
                ret = PTR_ERR(cc);
                goto fail;
@@ -2786,12 +2876,8 @@ static int dcss_pan_display(struct fb_var_screeninfo *var,
 
        commit_cfifo(fbi->node, info, cc);
 
-       flush_cfifo(&info->cfifo, &cc->work);
-
-       /* TODO: blocking mode */
-       if (likely(!var->reserved[2]))
-               /* make pan display synchronously */
-               finish_cfifo(&info->cfifo);
+       release_cc(cc);
+#endif
 
        goto out;
 
@@ -2908,6 +2994,7 @@ static irqreturn_t dcss_irq_handler(int irq, void *dev_id)
        struct dcss_channels *chans = &info->chans;
        struct dcss_channel_info *chan;
        struct ctxld_fifo *cfifo;
+       struct ctxld_commit *cc;
 
        cfifo = &info->cfifo;
        desc = irq_to_desc(irq);
@@ -2932,6 +3019,18 @@ static irqreturn_t dcss_irq_handler(int irq, void *dev_id)
                spin_lock_irqsave(&info->vinfo.vwait.lock, irqflags);
 
                info->vinfo.vcount++;
+               if (!list_empty(&cfifo->ctxld_list)) {
+                       cc = list_first_entry(&cfifo->ctxld_list,
+                                             struct ctxld_commit,
+                                             list);
+                       /* defer cfifo flush to next frame window */
+                       if (atomic_read(&cc->refcount))
+                               defer_flush_cfifo(cfifo);
+                       else {
+                               list_del(&cc->list);
+                               flush_cfifo(cfifo, &cc->work);
+                       }
+               }
 
                spin_unlock_irqrestore(&info->vinfo.vwait.lock, irqflags);