1 files changed, 47 insertions, 0 deletions

diff --git a/firmware/target/arm/ipod/video/lcd-video.c b/firmware/target/arm/ipod/video/lcd-video.c
index 494bec8429..27d889aafa 100644
--- a/firmware/target/arm/ipod/video/lcd-video.c
+++ b/firmware/target/arm/ipod/video/lcd-video.c
@@ -439,6 +439,53 @@ void lcd_update(void)
     lcd_update_rect(0, 0, LCD_WIDTH, LCD_HEIGHT);
 }
 
+/* Line write helper function for lcd_yuv_blit. Writes two lines of yuv420. */
+extern void lcd_write_yuv420_lines(unsigned char const * const src[3],
+                                   unsigned bcmaddr,
+                                   int width,
+                                   int stride);
+
+/* Performance function to blit a YUV bitmap directly to the LCD */
+void lcd_blit_yuv(unsigned char * const src[3],
+                  int src_x, int src_y, int stride,
+                  int x, int y, int width, int height)
+{
+    unsigned bcmaddr;
+    off_t z;
+    unsigned char const * yuv_src[3];
+
+#ifdef HAVE_LCD_SLEEP
+    if (!lcd_state.display_on)
+        return;
+#endif
+
+    /* Sorry, but width and height must be >= 2 or else */
+    width &= ~1;
+
+    z = stride * src_y;
+    yuv_src[0] = src[0] + z + src_x;
+    yuv_src[1] = src[1] + (z >> 2) + (src_x >> 1);
+    yuv_src[2] = src[2] + (yuv_src[1] - src[1]);
+
+    /* Prevent the tick from triggering BCM updates while we're writing. */
+    lcd_block_tick();
+
+    bcmaddr = BCMA_CMDPARAM + (LCD_WIDTH*2) * y + (x << 1);
+    height >>= 1;
+
+    do
+    {
+        lcd_write_yuv420_lines(yuv_src, bcmaddr, width, stride);
+        bcmaddr += (LCD_WIDTH*4);  /* Skip up two lines */
+        yuv_src[0] += stride << 1;
+        yuv_src[1] += stride >> 1; /* Skip down one chroma line */
+        yuv_src[2] += stride >> 1;
+    }
+    while (--height > 0);
+
+    lcd_unblock_and_update();
+}
+
 #ifdef HAVE_LCD_SLEEP
 /* Executes a BCM command immediately and waits for it to complete.
    Other BCM commands (eg. LCD updates or lcd_tick) must not interfere.