touch: get calibration info from OS, if known

include/gint/touch.h

@@ -26,6 +26,10 @@ typedef struct {
 /* touch_calib_get() - get calibration information */
 extern int touch_calib_get(touch_calibration_t *calib);
 
+/* touch_calib_get_os() - get OS calibration information, if available
+   Returns 0 on success, negative number if not available. */
+extern int touch_calib_get_os(touch_calibration_t *calib);
+
 /* touch_calib_set() - set calibration information */
 extern int touch_calib_set(touch_calibration_t *calib);
 

src/render-cg/dclear.c

@@ -7,8 +7,9 @@ void dclear(uint16_t color)
 {
 	// TODO: CP: DMA support for dclear()
 #if GINT_HW_CP
-	for(int i = 0; i < DWIDTH * DHEIGHT; i++)
-		gint_vram[i] = color;
+	uint32_t color4 = (color << 16) | color;
+	for(int i = 0; i < DWIDTH * DHEIGHT / 2; i++)
+		((uint32_t *)gint_vram)[i] = color4;
 #else
 	bool full_width = (dwindow.left == 0 && dwindow.right == DWIDTH);
 	bool dma_aligned = !(dwindow.top & 3) && !(dwindow.bottom & 3);

src/touch/driver.c

@@ -37,6 +37,8 @@ static void _touch_configure(void)
     __touch_drv_info.calibration.dual_debounce_frame = 0;
     __touch_drv_info.calibration.dual_sensi_entry = 0x18;
     __touch_drv_info.calibration.dual_sensi_leave = 0x24;
+
+    touch_calib_get_os(&__touch_drv_info.calibration);
 }
 
 /* _touch_hsave() - save hardware state */

src/touch/touch.c

@@ -35,6 +35,22 @@ int touch_calib_get(touch_calibration_t *calib)
     return 0;
 }
 
+int touch_calib_get_os(touch_calibration_t *calib)
+{
+    void *os_version = (void *)0x80020020;
+    if(!memcmp(os_version, "02.01.200", 9) ||
+       !memcmp(os_version, "02.01.700", 9)) {
+        int const *os_calibration = (void *)0x8c1bea50;
+        calib->x_base = os_calibration[0];
+        calib->y_base = os_calibration[1];
+        calib->x_div = os_calibration[2];
+        calib->y_div = os_calibration[3];
+        return 0;
+    }
+
+    return -1;
+}
+
 /* touch_calib_set() - set calibration information */
 int touch_calib_set(touch_calibration_t *calib)
 {