fix(core): improve tearing effect prevention

[no changelog]

core/embed/extmod/modtrezorui/display_interface.h

@@ -43,6 +43,7 @@ int display_backlight(int val);
 
 void display_init(void);
 void display_reinit(void);
+void display_sync(void);
 void display_refresh(void);
 const char *display_save(const char *prefix);
 void display_clear_save(void);

core/embed/rust/build.rs

@@ -293,6 +293,7 @@ fn generate_trezorhal_bindings() {
         .allowlist_function("display_pixeldata")
         .allowlist_function("display_pixeldata_dirty")
         .allowlist_function("display_set_window")
+        .allowlist_function("display_sync")
         .allowlist_var("DISPLAY_CMD_ADDRESS")
         .allowlist_var("DISPLAY_DATA_ADDRESS")
         .allowlist_type("toif_format_t")

core/embed/rust/src/trezorhal/display.rs

@@ -169,3 +169,9 @@ pub fn get_offset() -> (i16, i16) {
         (x as i16, y as i16)
     }
 }
+
+pub fn sync() {
+    unsafe {
+        ffi::display_sync();
+    }
+}

core/embed/rust/src/ui/display/mod.rs

@@ -826,6 +826,10 @@ pub fn set_window(window: Rect) {
     );
 }
 
+pub fn sync() {
+    display::sync();
+}
+
 pub fn get_color_table(fg_color: Color, bg_color: Color) -> [Color; 16] {
     let mut table: [Color; 16] = [Color::from_u16(0); 16];
 

core/embed/rust/src/ui/layout/obj.rs

@@ -18,6 +18,7 @@ use crate::{
     ui::{
         component::{Child, Component, Event, EventCtx, Never, TimerToken},
         constant,
+        display::sync,
         geometry::Rect,
     },
 };
@@ -200,6 +201,8 @@ impl LayoutObj {
             unsafe { Gc::as_mut(&mut inner.root) }.obj_place(constant::screen());
         }
 
+        sync();
+
         // SAFETY: `inner.root` is unique because of the `inner.borrow_mut()`.
         unsafe { Gc::as_mut(&mut inner.root) }.obj_paint()
     }

core/embed/trezorhal/common.c

@@ -192,6 +192,7 @@ void collect_hw_entropy(void) {
 void ensure_compatible_settings(void) {
 #ifdef TREZOR_MODEL_T
   display_set_big_endian();
+  display_orientation(0);
   set_core_clock(CLOCK_168_MHZ);
   display_set_slow_pwm();
 #endif

core/embed/trezorhal/displays/st7789v.c

@@ -151,11 +151,20 @@ int display_orientation(int degrees) {
     if (degrees == 0 || degrees == 90 || degrees == 180 || degrees == 270) {
       DISPLAY_ORIENTATION = degrees;
 
+      display_set_window(0, 0, MAX_DISPLAY_RESX - 1, MAX_DISPLAY_RESY - 1);
+      for (uint32_t i = 0; i < MAX_DISPLAY_RESX * MAX_DISPLAY_RESY; i++) {
+        // 2 bytes per pixel because we're using RGB 5-6-5 format
+        PIXELDATA(0x0000);
+      }
+
+      uint16_t shift = 0;
       char BX = 0, BY = 0;
       uint32_t id = display_identify();
       if ((id == DISPLAY_ID_ILI9341V) || (id == DISPLAY_ID_GC9307) ||
           (id == DISPLAY_ID_ST7789V)) {
 #define RGB (1 << 3)
+#define ML (1 << 4)  // vertical refresh order
+#define MH (1 << 2)  // horizontal refresh order
 #define MV (1 << 5)
 #define MX (1 << 6)
 #define MY (1 << 7)
@@ -170,12 +179,14 @@ int display_orientation(int degrees) {
             BY = (id == DISPLAY_ID_GC9307);
             break;
           case 90:
-            display_command_parameter = MV | MX;
+            display_command_parameter = MV | MX | MH | ML;
-            BX = (id == DISPLAY_ID_GC9307);
+            BX = (id != DISPLAY_ID_GC9307);
+            shift = 1;
             break;
           case 180:
-            display_command_parameter = MX | MY;
+            display_command_parameter = MX | MY | MH | ML;
-            BY = (id != DISPLAY_ID_GC9307);
+            BY = (id == DISPLAY_ID_GC9307);
+            shift = 1;
             break;
           case 270:
             display_command_parameter = MV | MY;
@@ -187,6 +198,23 @@ int display_orientation(int degrees) {
         }
         CMD(0x36);
         DATA(display_command_parameter);
+
+        if (shift) {
+          // GATECTRL: Gate Control; NL = 240 gate lines, first scan line is
+          // gate 80.; gate scan direction 319 -> 0
+          CMD(0xE4);
+          DATA(0x1D);
+          DATA(0x00);
+          DATA(0x11);
+        } else {
+          // GATECTRL: Gate Control; NL = 240 gate lines, first scan line is
+          // gate 80.; gate scan direction 319 -> 0
+          CMD(0xE4);
+          DATA(0x1D);
+          DATA(0x0A);
+          DATA(0x11);
+        }
+
         // reset the column and page extents
         display_set_window(0, 0, DISPLAY_RESX - 1, DISPLAY_RESY - 1);
       }
@@ -634,18 +662,20 @@ void display_reinit(void) {
   display_backlight(DISPLAY_BACKLIGHT);
 }
 
-void display_refresh(void) {
+void display_sync(void) {
   uint32_t id = display_identify();
   if (id && (id != DISPLAY_ID_GC9307)) {
     // synchronize with the panel synchronization signal
     // in order to avoid visual tearing effects
-    while (GPIO_PIN_RESET == HAL_GPIO_ReadPin(GPIOD, GPIO_PIN_12)) {
-    }
     while (GPIO_PIN_SET == HAL_GPIO_ReadPin(GPIOD, GPIO_PIN_12)) {
     }
+    while (GPIO_PIN_RESET == HAL_GPIO_ReadPin(GPIOD, GPIO_PIN_12)) {
+    }
   }
 }
 
+void display_refresh(void) {}
+
 void display_set_slow_pwm(void) {
   // enable PWM timer
   TIM_HandleTypeDef TIM1_Handle;

core/embed/trezorhal/displays/ug-2828tswig01.c

@@ -347,6 +347,8 @@ void display_init(void) {
   display_init_seq();
 }
 
+void display_sync(void) {}
+
 void display_refresh(void) {
   for (int y = 0; y < (DISPLAY_RESY / 8); y++) {
     display_set_page_and_col(y, 0);

core/embed/trezorhal/displays/vg-2864ksweg01.c

@@ -247,6 +247,8 @@ static void rotate_oled_buffer(void) {
   }
 }
 
+void display_sync(void) {}
+
 void display_refresh(void) {
   static const uint8_t s[3] = {OLED_SETLOWCOLUMN | 0x00,
                                OLED_SETHIGHCOLUMN | 0x00,

core/embed/unix/display-unix.c

@@ -234,6 +234,8 @@ void display_set_window(uint16_t x0, uint16_t y0, uint16_t x1, uint16_t y1) {
   PIXELWINDOW.pos.y = y0;
 }
 
+void display_sync(void) {}
+
 void display_refresh(void) {
   if (!RENDERER) {
     display_init();