From: Gary King <gking@nvidia.com>
Date: Sun, 15 Aug 2010 18:26:49 +0000 (-0700)
Subject: video: tegra: add utility function to compute framebuffer stride
X-Git-Tag: firefly_0821_release~9833^2~163^2~5
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=10c751b8f5bb78f674d4939b47be933934bb23dd;p=firefly-linux-kernel-4.4.55.git

video: tegra: add utility function to compute framebuffer stride

framebuffers will generally not be exactly width * bpp / 8 bytes wide;
on tegra, linearly-addressed framebuffers will generally be rounded
up so that the stride is a multiple of 16B (so that they are compatible
with rendering from the hardware engines), and tiled framebuffers
will be a multiple of the tile width (64B).

add a utility function to tegra_dc to compute the correct stride
given a width, bpp and pixel layout, and use this in set_par.

Change-Id: I803a55b49c12476f20d5644707899c3fe1336c2d
Signed-off-by: Gary King <gking@nvidia.com>
---

diff --git a/arch/arm/mach-tegra/include/mach/dc.h b/arch/arm/mach-tegra/include/mach/dc.h
index ae0273ca057d..ce562e5634f7 100644
--- a/arch/arm/mach-tegra/include/mach/dc.h
+++ b/arch/arm/mach-tegra/include/mach/dc.h
@@ -25,6 +25,15 @@
 #define TEGRA_MAX_DC		2
 #define DC_N_WINDOWS		3
 
+#define TEGRA_DC_PITCH_ATOM	16
+#define TEGRA_DC_TILED_ATOM	16
+
+enum tegra_win_layout {
+	TEGRA_WIN_LAYOUT_PITCH,
+	TEGRA_WIN_LAYOUT_TILED,
+	TEGRA_WIN_LAYOUT_LINEAR_TILED,
+};
+
 struct tegra_dc_mode {
 	int	pclk;
 	int	h_ref_to_sync;
@@ -95,6 +104,7 @@ struct tegra_dc_win {
 	unsigned		out_w;
 	unsigned		out_h;
 	unsigned		z;
+	enum tegra_win_layout	layout;
 
 	int			dirty;
 	struct tegra_dc		*dc;
@@ -163,4 +173,7 @@ int tegra_dc_sync_windows(struct tegra_dc_win *windows[], int n);
 
 int tegra_dc_set_mode(struct tegra_dc *dc, const struct tegra_dc_mode *mode);
 
+ssize_t tegra_dc_compute_stride(int xres, int bpp,
+				enum tegra_win_layout layout);
+
 #endif
diff --git a/drivers/video/tegra/dc/dc.c b/drivers/video/tegra/dc/dc.c
index 55ecf100de05..fadecf4796e1 100644
--- a/drivers/video/tegra/dc/dc.c
+++ b/drivers/video/tegra/dc/dc.c
@@ -325,6 +325,20 @@ struct tegra_dc *tegra_dc_get_dc(unsigned idx)
 }
 EXPORT_SYMBOL(tegra_dc_get_dc);
 
+ssize_t tegra_dc_compute_stride(int xres, int bpp, enum tegra_win_layout layout)
+{
+	unsigned int raw_stride = (xres * bpp) / 8;
+	unsigned int k, n = 0;
+
+	if (layout == TEGRA_WIN_LAYOUT_PITCH)
+		return ALIGN(raw_stride, TEGRA_DC_PITCH_ATOM);
+	else if (layout == TEGRA_WIN_LAYOUT_TILED)
+		return ALIGN(raw_stride, TEGRA_DC_TILED_ATOM);
+	else
+		return -EINVAL;
+}
+EXPORT_SYMBOL(tegra_dc_compute_stride);
+
 struct tegra_dc_win *tegra_dc_get_window(struct tegra_dc *dc, unsigned win)
 {
 	if (win >= dc->n_windows)
diff --git a/drivers/video/tegra/fb.c b/drivers/video/tegra/fb.c
index ac07c551fb5d..7e4ffa8ba0b9 100644
--- a/drivers/video/tegra/fb.c
+++ b/drivers/video/tegra/fb.c
@@ -113,7 +113,10 @@ static int tegra_fb_set_par(struct fb_info *info)
 	default:
 		return -EINVAL;
 	}
-	info->fix.line_length = var->xres * var->bits_per_pixel / 8;
+
+	info->fix.line_length = tegra_dc_compute_stride(var->xres,
+			var->bits_per_pixel, TEGRA_WIN_LAYOUT_PITCH);
+	tegra_fb->win->stride = info->fix.line_length;
 
 	if (var->pixclock) {
 		struct tegra_dc_mode mode;
@@ -371,7 +374,9 @@ struct tegra_fb_info *tegra_fb_register(struct nvhost_device *ndev,
 	win->z = 0;
 	win->phys_addr = fb_phys;
 	win->virt_addr = fb_base;
-	win->stride = fb_data->xres * fb_data->bits_per_pixel / 8;
+	win->layout = TEGRA_WIN_LAYOUT_PITCH;
+	win->stride = tegra_dc_compute_stride(fb_data->xres,
+				      fb_data->bits_per_pixel, win->layout);
 	win->flags = TEGRA_WIN_FLAG_ENABLED;
 
 	if (fb_mem)