From: Stephen Warren <swarren@wwwdotorg.org>
Date: Mon, 27 May 2013 18:31:17 +0000 (+0000)
Subject: lcd: add functions to set up simplefb device tree
X-Git-Tag: v2025.01-rc5-pxa1908~16199^2~1
X-Git-Url: http://git.dujemihanovic.xyz/html/static/git-logo.png?a=commitdiff_plain;h=6a195d2d8a9c321817e1f034afcdc8c8642664bc;p=u-boot.git
lcd: add functions to set up simplefb device tree
simple-framebuffer is a new device tree binding that describes a pre-
configured frame-buffer memory region and its format. The Linux kernel
contains a driver that supports this binding. Implement functions to
create a DT node (or fill in an existing node) with parameters that
describe the framebuffer format that U-Boot is using.
This will be immediately used by the Raspberry Pi board in U-Boot, and
likely will be used by the Samsung ARM ChromeBook support soon too. It
could well be used by many other boards (e.g. Tegra boards with built-in
LCD panels, which aren't yet supported by the Linux kernel).
Signed-off-by: Stephen Warren <swarren@wwwdotorg.org>
Acked-by: Simon Glass <sjg@chromium.org>
---
diff --git a/common/lcd.c b/common/lcd.c
index edae835fb0..3a60484eea 100644
--- a/common/lcd.c
+++ b/common/lcd.c
@@ -57,6 +57,10 @@
#include <atmel_lcdc.h>
#endif
+#if defined(CONFIG_LCD_DT_SIMPLEFB)
+#include <libfdt.h>
+#endif
+
/************************************************************************/
/* ** FONT DATA */
/************************************************************************/
@@ -1182,3 +1186,86 @@ int lcd_get_screen_columns(void)
{
return CONSOLE_COLS;
}
+
+#if defined(CONFIG_LCD_DT_SIMPLEFB)
+static int lcd_dt_simplefb_configure_node(void *blob, int off)
+{
+ u32 stride;
+ fdt32_t cells[2];
+ int ret;
+ const char format[] =
+#if LCD_BPP == LCD_COLOR16
+ "r5g6b5";
+#else
+ "";
+#endif
+
+ if (!format[0])
+ return -1;
+
+ stride = panel_info.vl_col * 2;
+
+ cells[0] = cpu_to_fdt32(gd->fb_base);
+ cells[1] = cpu_to_fdt32(stride * panel_info.vl_row);
+ ret = fdt_setprop(blob, off, "reg", cells, sizeof(cells[0]) * 2);
+ if (ret < 0)
+ return -1;
+
+ cells[0] = cpu_to_fdt32(panel_info.vl_col);
+ ret = fdt_setprop(blob, off, "width", cells, sizeof(cells[0]));
+ if (ret < 0)
+ return -1;
+
+ cells[0] = cpu_to_fdt32(panel_info.vl_row);
+ ret = fdt_setprop(blob, off, "height", cells, sizeof(cells[0]));
+ if (ret < 0)
+ return -1;
+
+ cells[0] = cpu_to_fdt32(stride);
+ ret = fdt_setprop(blob, off, "stride", cells, sizeof(cells[0]));
+ if (ret < 0)
+ return -1;
+
+ ret = fdt_setprop(blob, off, "format", format, strlen(format) + 1);
+ if (ret < 0)
+ return -1;
+
+ ret = fdt_delprop(blob, off, "status");
+ if (ret < 0)
+ return -1;
+
+ return 0;
+}
+
+int lcd_dt_simplefb_add_node(void *blob)
+{
+ const char compat[] = "simple-framebuffer";
+ const char disabled[] = "disabled";
+ int off, ret;
+
+ off = fdt_add_subnode(blob, 0, "framebuffer");
+ if (off < 0)
+ return -1;
+
+ ret = fdt_setprop(blob, off, "status", disabled, sizeof(disabled));
+ if (ret < 0)
+ return -1;
+
+ ret = fdt_setprop(blob, off, "compatible", compat, sizeof(compat));
+ if (ret < 0)
+ return -1;
+
+ return lcd_dt_simplefb_configure_node(blob, off);
+}
+
+int lcd_dt_simplefb_enable_existing_node(void *blob)
+{
+ int off;
+
+ off = fdt_node_offset_by_compatible(blob, -1, "simple-framebuffer");
+ if (off < 0)
+ return -1;
+
+ return lcd_dt_simplefb_configure_node(blob, off);
+}
+#endif
diff --git a/doc/device-tree-bindings/video/simple-framebuffer.txt b/doc/device-tree-bindings/video/simple-framebuffer.txt
new file mode 100644
index 0000000000..3ea4605831
--- /dev/null
+++ b/doc/device-tree-bindings/video/simple-framebuffer.txt
@@ -0,0 +1,25 @@
+Simple Framebuffer
+
+A simple frame-buffer describes a raw memory region that may be rendered to,
+with the assumption that the display hardware has already been set up to scan
+out from that buffer.
+
+Required properties:
+- compatible: "simple-framebuffer"
+- reg: Should contain the location and size of the framebuffer memory.
+- width: The width of the framebuffer in pixels.
+- height: The height of the framebuffer in pixels.
+- stride: The number of bytes in each line of the framebuffer.
+- format: The format of the framebuffer surface. Valid values are:
+ - r5g6b5 (16-bit pixels, d[15:11]=r, d[10:5]=g, d[4:0]=b).
+
+Example:
+
+ framebuffer {
+ compatible = "simple-framebuffer";
+ reg = <0x1d385000 (1600 * 1200 * 2)>;
+ width = <1600>;
+ height = <1200>;
+ stride = <(1600 * 2)>;
+ format = "r5g6b5";
+ };
diff --git a/include/lcd.h b/include/lcd.h
index c6e7fc5216..30225edf56 100644
--- a/include/lcd.h
+++ b/include/lcd.h
@@ -324,6 +324,9 @@ void lcd_show_board_info(void);
/* Return the size of the LCD frame buffer, and the line length */
int lcd_get_size(int *line_length);
+int lcd_dt_simplefb_add_node(void *blob);
+int lcd_dt_simplefb_enable_existing_node(void *blob);
+
/************************************************************************/
/* ** BITMAP DISPLAY SUPPORT */
/************************************************************************/