[PATCH 14/15] drm/exynos/fimc: simplify buffer queuing

[Andrzej Hajda]

The patch removes redundant checks, redundant HW reads
and simplifies code.

Signed-off-by: Andrzej Hajda <a.hajda at samsung.com>
---
 drivers/gpu/drm/exynos/exynos_drm_fimc.c | 64 ++++++++------------------------
 1 file changed, 15 insertions(+), 49 deletions(-)

diff --git a/drivers/gpu/drm/exynos/exynos_drm_fimc.c 
b/drivers/gpu/drm/exynos/exynos_drm_fimc.c
index bd6628d..b20078e 100644
--- a/drivers/gpu/drm/exynos/exynos_drm_fimc.c
+++ b/drivers/gpu/drm/exynos/exynos_drm_fimc.c
@@ -1124,67 +1124,34 @@ static int fimc_dst_set_size(struct device *dev, int 
swap,
        return 0;
 }

-static int fimc_dst_get_buf_count(struct fimc_context *ctx)
-{
-       u32 cfg, buf_num;
-
-       cfg = fimc_read(ctx, EXYNOS_CIFCNTSEQ);
-
-       buf_num = hweight32(cfg);
-
-       DRM_DEBUG_KMS("buf_num[%d]\n", buf_num);
-
-       return buf_num;
-}
-
-static int fimc_dst_set_buf_seq(struct fimc_context *ctx, u32 buf_id,
+static void fimc_dst_set_buf_seq(struct fimc_context *ctx, u32 buf_id,
                enum drm_exynos_ipp_buf_type buf_type)
 {
-       struct exynos_drm_ippdrv *ippdrv = &ctx->ippdrv;
-       bool enable;
-       u32 cfg;
-       u32 mask = 0x00000001 << buf_id;
-       int ret = 0;
        unsigned long flags;
+       u32 buf_num;
+       u32 cfg;

        DRM_DEBUG_KMS("buf_id[%d]buf_type[%d]\n", buf_id, buf_type);

        spin_lock_irqsave(&ctx->lock, flags);

-       /* mask register set */
        cfg = fimc_read(ctx, EXYNOS_CIFCNTSEQ);

-       switch (buf_type) {
-       case IPP_BUF_ENQUEUE:
-               enable = true;
-               break;
-       case IPP_BUF_DEQUEUE:
-               enable = false;
-               break;
-       default:
-               dev_err(ippdrv->dev, "invalid buf ctrl parameter.\n");
-               ret =  -EINVAL;
-               goto err_unlock;
-       }
+       if (buf_type == IPP_BUF_ENQUEUE)
+               cfg |= (1 << buf_id);
+       else
+               cfg &= (1 << buf_id);

-       /* sequence id */
-       cfg &= ~mask;
-       cfg |= (enable << buf_id);
        fimc_write(ctx, cfg, EXYNOS_CIFCNTSEQ);

-       /* interrupt enable */
-       if (buf_type == IPP_BUF_ENQUEUE &&
-           fimc_dst_get_buf_count(ctx) >= FIMC_BUF_START)
-               fimc_mask_irq(ctx, true);
+       buf_num = hweight32(cfg);

-       /* interrupt disable */
-       if (buf_type == IPP_BUF_DEQUEUE &&
-           fimc_dst_get_buf_count(ctx) <= FIMC_BUF_STOP)
+       if (buf_type == IPP_BUF_ENQUEUE && buf_num >= FIMC_BUF_START)
+               fimc_mask_irq(ctx, true);
+       else if (buf_type == IPP_BUF_DEQUEUE && buf_num <= FIMC_BUF_STOP)
                fimc_mask_irq(ctx, false);

-err_unlock:
        spin_unlock_irqrestore(&ctx->lock, flags);
-       return ret;
 }

 static int fimc_dst_set_addr(struct device *dev,
@@ -1242,7 +1209,9 @@ static int fimc_dst_set_addr(struct device *dev,
                break;
        }

-       return fimc_dst_set_buf_seq(ctx, buf_id, buf_type);
+       fimc_dst_set_buf_seq(ctx, buf_id, buf_type);
+
+       return 0;
 }

 static struct exynos_drm_ipp_ops fimc_dst_ops = {
@@ -1297,10 +1266,7 @@ static irqreturn_t fimc_irq_handler(int irq, void 
*dev_id)

        DRM_DEBUG_KMS("buf_id[%d]\n", buf_id);

-       if (fimc_dst_set_buf_seq(ctx, buf_id, IPP_BUF_DEQUEUE) < 0) {
-               DRM_ERROR("failed to dequeue.\n");
-               return IRQ_HANDLED;
-       }
+       fimc_dst_set_buf_seq(ctx, buf_id, IPP_BUF_DEQUEUE);

        event_work->ippdrv = ippdrv;
        event_work->buf_id[EXYNOS_DRM_OPS_DST] = buf_id;
-- 
1.9.1