diff options
| author | Tobias Jakobi <tjakobi@math.uni-bielefeld.de> | 2015-02-24 15:20:40 +0100 |
|---|---|---|
| committer | Emil Velikov <emil.l.velikov@gmail.com> | 2015-03-10 19:04:35 +0000 |
| commit | 1d7e78d7877f054f7b96d6a35d50255e76aed44f (patch) | |
| tree | 1f78133802b99ea91f1ac0daf3055b70c6cc6cfc | |
| parent | 0ca03a4087a550646de7f26b6b53a932e8546474 (diff) | |
exynos: replace G2D_DOUBLE_TO_FIXED macro with function
This also avoids the floating point conversion steps and just
uses pure integer arithmetic.
Since the G2D hardware scaling approach is a bit unintuitive,
document it in the function as well.
v2: Explicitly mention the normalization constant.
v3: Use common commenting style as pointed out by
Emil Velikov <emil.l.velikov@gmail.com>.
Signed-off-by: Tobias Jakobi <tjakobi@math.uni-bielefeld.de>
Reviewed-by: Emil Velikov <emil.l.velikov@gmail.com>
Tested-by: Joonyoung Shim <jy0922.shim@samsung.com>
| -rw-r--r-- | exynos/exynos_fimg2d.c | 22 | ||||
| -rw-r--r-- | exynos/fimg2d.h | 2 |
2 files changed, 17 insertions, 7 deletions
diff --git a/exynos/exynos_fimg2d.c b/exynos/exynos_fimg2d.c index ce1ba1ef..9c66c3ab 100644 --- a/exynos/exynos_fimg2d.c +++ b/exynos/exynos_fimg2d.c @@ -41,6 +41,18 @@ #define MIN(a, b) ((a) < (b) ? (a) : (b)) +static unsigned int g2d_get_scaling(unsigned int src, unsigned int dst) +{ + /* + * The G2D hw scaling factor is a normalized inverse of the scaling factor. + * For example: When source width is 100 and destination width is 200 + * (scaling of 2x), then the hw factor is NC * 100 / 200. + * The normalization factor (NC) is 2^16 = 0x10000. + */ + + return ((src << 16) / dst); +} + static unsigned int g2d_get_blend_op(enum e_g2d_op op) { union g2d_blend_func_val val; @@ -428,7 +440,7 @@ g2d_copy_with_scale(struct g2d_context *ctx, struct g2d_image *src, union g2d_rop4_val rop4; union g2d_point_val pt; unsigned int scale; - double scale_x = 0.0f, scale_y = 0.0f; + unsigned int scale_x, scale_y; g2d_add_cmd(ctx, DST_SELECT_REG, G2D_SELECT_MODE_BGCOLOR); g2d_add_cmd(ctx, DST_COLOR_MODE_REG, dst->color_mode); @@ -454,8 +466,8 @@ g2d_copy_with_scale(struct g2d_context *ctx, struct g2d_image *src, scale = 0; else { scale = 1; - scale_x = (double)src_w / (double)dst_w; - scale_y = (double)src_h / (double)dst_h; + scale_x = g2d_get_scaling(src_w, dst_w); + scale_y = g2d_get_scaling(src_h, dst_h); } if (src_x + src_w > src->width) @@ -487,8 +499,8 @@ g2d_copy_with_scale(struct g2d_context *ctx, struct g2d_image *src, if (scale) { g2d_add_cmd(ctx, SRC_SCALE_CTRL_REG, G2D_SCALE_MODE_BILINEAR); - g2d_add_cmd(ctx, SRC_XSCALE_REG, G2D_DOUBLE_TO_FIXED(scale_x)); - g2d_add_cmd(ctx, SRC_YSCALE_REG, G2D_DOUBLE_TO_FIXED(scale_y)); + g2d_add_cmd(ctx, SRC_XSCALE_REG, scale_x); + g2d_add_cmd(ctx, SRC_YSCALE_REG, scale_y); } pt.val = 0; diff --git a/exynos/fimg2d.h b/exynos/fimg2d.h index 4785e2f0..8e0321cf 100644 --- a/exynos/fimg2d.h +++ b/exynos/fimg2d.h @@ -25,8 +25,6 @@ #define G2D_MAX_CMD_LIST_NR 64 #define G2D_PLANE_MAX_NR 2 -#define G2D_DOUBLE_TO_FIXED(d) ((unsigned int)((d) * 65536.0)) - enum e_g2d_color_mode { /* COLOR FORMAT */ G2D_COLOR_FMT_XRGB8888, |