ui: introduce double buffering

scripts/jlink-bootloader.gdb

@@ -1,12 +1,16 @@
 # Connect to jlink gdb server
 target extended-remote :2331
 
-# load the firmware into ROM
-load
+# It seems more reliable to reset the chip before loading the new firmware. It
+# is also how they do it in the example in the wiki:
+# https://kb.segger.com/J-Link_GDB_Server#Console
 
 # Reset the CPU
 monitor reset
 
+# load the firmware into ROM
+load
+
 #break Reset_Handler
 #break HardFault_Handler
 #break NMI_Handler

scripts/jlink.gdb

@@ -1,12 +1,16 @@
 # Connect to jlink gdb server
 target extended-remote :2331
 
-# load the firmware into ROM
-load
+# It seems more reliable to reset the chip before loading the new firmware. It
+# is also how they do it in the example in the wiki:
+# https://kb.segger.com/J-Link_GDB_Server#Console
 
 # Reset the CPU
 monitor reset
 
+# load the firmware into ROM
+load
+
 # Set VTOR (Vector Table Offset Register) to where the firmware is located
 set *(uint32_t*)0xE000ED08=0x10000
 # Set stack pointer to initial stack pointer according to exception table.

src/CMakeLists.txt

@@ -128,6 +128,7 @@ set(DRIVER-SOURCES
   ${CMAKE_SOURCE_DIR}/src/platform/driver_init.c
   ${CMAKE_SOURCE_DIR}/src/ui/oled/oled.c
   ${CMAKE_SOURCE_DIR}/src/ui/oled/oled_writer.c
+  ${CMAKE_SOURCE_DIR}/src/ui/canvas.c
 )
 set(DRIVER-SOURCES ${DRIVER-SOURCES} PARENT_SCOPE)
 

src/bootloader/bootloader.c

@@ -26,6 +26,7 @@
 #include <screen.h>
 #include <stdint.h>
 #include <string.h>
+#include <ui/canvas.h>
 #include <ui/components/ui_images.h>
 #include <ui/fonts/arial_fonts.h>
 #include <ui/graphics/graphics.h>
@@ -328,15 +329,14 @@ static void _render_message(const char* message, int duration)
 {
     char print[100];
     snprintf(print, sizeof(print), "%s", message);
-    UG_ClearBuffer();
     UG_PutString(0, 0, print, false);
-    UG_SendBuffer();
+    canvas_commit();
+    oled_blit();
     delay_ms(duration);
 }
 
 void bootloader_render_default_screen(void)
 {
-    UG_ClearBuffer();
     _load_logo();
 #if PLATFORM_BITBOX02PLUS == 1
     UG_PutString(0, SCREEN_HEIGHT - 9 * 2 - 5, "See the BitBoxApp", false);
@@ -354,7 +354,8 @@ void bootloader_render_default_screen(void)
     }
     UG_PutString(0, SCREEN_HEIGHT - 9, "See the BitBoxApp", false);
 #endif
-    UG_SendBuffer();
+    canvas_commit();
+    oled_blit();
 }
 
 #if PLATFORM_BITBOX02PLUS
@@ -368,7 +369,6 @@ void bootloader_render_ble_confirm_screen(bool confirmed)
     uint32_t pairing_code_int = (*(uint32_t*)&bootloader_pairing_code_bytes[0]) % 1000000;
     char code_str[10] = {0};
     snprintf(code_str, sizeof(code_str), "%06u", (unsigned)pairing_code_int);
-    UG_ClearBuffer();
     uint16_t check_width = IMAGE_DEFAULT_CHECKMARK_HEIGHT + IMAGE_DEFAULT_CHECKMARK_HEIGHT / 2 - 1;
     if (confirmed) {
         UG_PutString(15, 0, "Confirm on app", false);
@@ -380,13 +380,13 @@ void bootloader_render_ble_confirm_screen(bool confirmed)
     UG_FontSelect(&font_monogram_5X9);
     UG_PutString(45, SCREEN_HEIGHT / 2 - 9, code_str, false);
     UG_FontSelect(&font_font_a_9X9);
-    UG_SendBuffer();
+    canvas_commit();
+    oled_blit();
 }
 #endif
 
 static void _render_progress(float progress)
 {
-    UG_ClearBuffer();
     _load_logo();
     if (progress > 0) {
         char label[5] = {0};
@@ -401,7 +401,8 @@ static void _render_progress(float progress)
         msg = "INSTALLING";
     }
     UG_PutString(SCREEN_WIDTH / 2 - 3, SCREEN_HEIGHT - 9 * 2, msg, false);
-    UG_SendBuffer();
+    canvas_commit();
+    oled_blit();
 }
 
 static void _render_hash(const char* title, const uint8_t* hash)
@@ -433,7 +434,6 @@ static void _render_hash(const char* title, const uint8_t* hash)
         &hash_hex[48]);
 
     for (uint8_t i = 1; i <= seconds; i++) {
-        UG_ClearBuffer();
         UG_PutString(0, 0, title, false);
 
         snprintf(timer_buf, sizeof(timer_buf), "%ds", seconds - i);
@@ -449,7 +449,8 @@ static void _render_hash(const char* title, const uint8_t* hash)
 
         UG_FontSelect(f_regular);
 
-        UG_SendBuffer();
+        canvas_commit();
+        oled_blit();
         delay_ms(1000);
     }
     bootloader_render_default_screen();
@@ -1013,7 +1014,6 @@ static void _check_init(boot_data_t* data)
 #ifdef BOOTLOADER_DEVDEVICE
 static bool _devdevice_enter(secbool_u32 firmware_verified)
 {
-    UG_ClearBuffer();
     UG_PutString(0, 0, "    <Enter bootloader>", false);
     UG_PutString(0, SCREEN_HEIGHT / 2 - 11, "DEV DEVICE", false);
     UG_PutString(0, SCREEN_HEIGHT / 2 + 2, "NOT FOR VALUE", false);
@@ -1043,7 +1043,8 @@ static bool _devdevice_enter(secbool_u32 firmware_verified)
         UG_DrawLine(xpos + 5, ypos, xpos, ypos + 5, C_WHITE);
         UG_DrawLine(xpos - 2, ypos + 3, xpos, ypos + 5, C_WHITE);
     }
-    UG_SendBuffer();
+    canvas_commit();
+    oled_blit();
     while (true) {
         do {
             qtouch_process();

src/bootloader/startup.c

@@ -22,6 +22,7 @@
 #include <rust/rust.h>
 #include <screen.h>
 #include <string.h>
+#include <ui/canvas.h>
 #include <ui/oled/oled.h>
 #include <usb/class/hid/hww/hid_hww.h>
 #include <usb/usb_processing.h>
@@ -83,7 +84,7 @@ int main(void)
     bootloader_init();
     platform_init();
     __stack_chk_guard = rand_sync_read32(&RAND_0);
-    screen_init(oled_set_pixel, oled_mirror, oled_clear_buffer);
+    screen_init(oled_set_pixel, oled_mirror);
 #if defined(BOOTLOADER_DEVDEVICE) || PLATFORM_BITBOX02PLUS == 1
     qtouch_init();
 #endif
@@ -189,7 +190,6 @@ int main(void)
 
             if (qtouch_is_scroller_active(top_slider)) {
                 bool ok;
-                UG_ClearBuffer();
                 if (qtouch_get_scroller_position(top_slider) < 127) {
                     bootloader_render_default_screen();
                     ok = false;
@@ -218,7 +218,8 @@ int main(void)
                     ringbuffer_put(&uart_write_queue, tmp[i]);
                 }
                 bootloader_pairing_request = false;
-                UG_SendBuffer();
+                canvas_commit();
+                oled_blit();
             }
         }
 #endif

src/factorysetup.c

@@ -577,7 +577,7 @@ int main(void)
     system_init();
     platform_init();
     __stack_chk_guard = common_stack_chk_guard();
-    screen_init(oled_set_pixel, oled_mirror, oled_clear_buffer);
+    screen_init(oled_set_pixel, oled_mirror);
     screen_splash();
     common_main();
 

src/firmware.c

@@ -41,7 +41,7 @@ int main(void)
     system_init();
     platform_init();
     __stack_chk_guard = common_stack_chk_guard();
-    screen_init(oled_set_pixel, oled_mirror, oled_clear_buffer);
+    screen_init(oled_set_pixel, oled_mirror);
     screen_splash();
     qtouch_init();
     common_main();

src/reset.c

@@ -23,12 +23,14 @@
 #include "system.h"
 #include "uart.h"
 #include <screen.h>
+#include <ui/canvas.h>
 
 #ifndef TESTING
 #include "securechip/securechip.h"
 #include <driver_init.h>
 #include <hal_delay.h>
 #include <ui/components/status.h>
+#include <ui/oled/oled.h>
 #include <ui/ugui/ugui.h>
 #endif
 
@@ -41,9 +43,10 @@ static void _show_reset_label(bool status)
 {
     const char* msg = "Device reset";
     component_t* comp = status_create(msg, status, NULL, NULL);
-    screen_clear();
+    canvas_clear();
     comp->f->render(comp);
-    UG_SendBuffer();
+    canvas_commit();
+    oled_blit();
     comp->f->cleanup(comp);
     delay_ms(3000);
 }

src/rust/bitbox02-rust/src/general/screen.rs

@@ -14,13 +14,14 @@
 
 use core::time::Duration;
 
-use bitbox02::{delay, ug_clear_buffer, ug_font_select_9x9, ug_put_string, ug_send_buffer};
+use bitbox02::{canvas_clear, canvas_commit, delay, oled_blit, ug_font_select_9x9, ug_put_string};
 
 pub fn print_debug_internal(duration: Duration, msg: &str) {
-    ug_clear_buffer();
+    canvas_clear();
     ug_font_select_9x9();
     ug_put_string(0, 0, msg, false);
-    ug_send_buffer();
+    canvas_commit();
+    oled_blit();
     delay(duration);
 }
 

src/rust/bitbox02-sys/build.rs

@@ -53,14 +53,14 @@ const ALLOWLIST_TYPES: &[&str] = &[
 ];
 
 const ALLOWLIST_FNS: &[&str] = &[
-    "UG_ClearBuffer",
     "UG_FontSelect",
     "UG_PutString",
-    "UG_SendBuffer",
     "bip32_derive_xpub",
     "bitbox02_smarteeprom_init",
     "bitbox_secp256k1_dleq_prove",
     "bitbox_secp256k1_dleq_verify",
+    "canvas_clear",
+    "canvas_commit",
     "confirm_create",
     "confirm_transaction_address_create",
     "confirm_transaction_fee_create",
@@ -114,6 +114,7 @@ const ALLOWLIST_FNS: &[&str] = &[
     "memory_get_platform",
     "memory_get_securechip_type",
     "memory_spi_get_active_ble_firmware_version",
+    "oled_blit",
     "spi_mem_protected_area_write",
     "menu_create",
     "fake_memory_factoryreset",
@@ -199,6 +200,7 @@ const BITBOX02_SOURCES: &[&str] = &[
     "src/u2f.c",
     "src/u2f/u2f_app.c",
     "src/u2f/u2f_packet.c",
+    "src/ui/canvas.c",
     "src/ui/components/button.c",
     "src/ui/components/confirm_gesture.c",
     "src/ui/components/confirm_transaction.c",
@@ -402,6 +404,7 @@ pub fn main() -> Result<(), &'static str> {
         "test/hardware-fakes/src/fake_component.c",
         "test/hardware-fakes/src/fake_diskio.c",
         "test/hardware-fakes/src/fake_memory.c",
+        "test/hardware-fakes/src/fake_oled.c",
         "test/hardware-fakes/src/fake_qtouch.c",
         "test/hardware-fakes/src/fake_screen.c",
         "test/hardware-fakes/src/fake_securechip.c",

src/rust/bitbox02-sys/wrapper.h

@@ -29,6 +29,7 @@
 #include <securechip/securechip.h>
 #include <system.h>
 #include <time.h>
+#include <ui/canvas.h>
 #include <ui/components/confirm.h>
 #include <ui/components/confirm_transaction.h>
 #include <ui/components/empty.h>

src/rust/bitbox02/src/lib.rs

@@ -62,12 +62,16 @@ pub fn ug_put_string(x: i16, y: i16, input: &str, inverted: bool) {
     }
 }
 
-pub fn ug_clear_buffer() {
-    unsafe { bitbox02_sys::UG_ClearBuffer() }
+pub fn canvas_clear() {
+    unsafe { bitbox02_sys::canvas_clear() }
 }
 
-pub fn ug_send_buffer() {
-    unsafe { bitbox02_sys::UG_SendBuffer() }
+pub fn canvas_commit() {
+    unsafe { bitbox02_sys::canvas_commit() }
+}
+
+pub fn oled_blit() {
+    unsafe { bitbox02_sys::oled_blit() }
 }
 
 pub fn ug_font_select_9x9() {

src/screen.c

@@ -18,6 +18,7 @@
 #include <stdbool.h>
 #include <stdint.h>
 #include <string.h>
+#include <ui/canvas.h>
 #include <ui/components/ui_images.h>
 #include <ui/fonts/arial_fonts.h>
 #include <ui/oled/oled.h>
@@ -32,7 +33,6 @@
 static UG_GUI guioled; // Global GUI structure for OLED screen
 static bool screen_upside_down = false;
 static void (*_mirror_fn)(bool);
-static void (*_clear_fn)(void);
 
 UG_COLOR screen_front_color = C_WHITE;
 UG_COLOR screen_back_color = C_BLACK;
@@ -45,10 +45,11 @@ void screen_print_debug(const char* message, int duration)
 {
     char print[100];
     snprintf(print, sizeof(print), "%s", message);
-    screen_clear();
+    canvas_clear();
     UG_FontSelect(&font_font_a_9X9);
     UG_PutString(0, 0, print, false);
-    UG_SendBuffer();
+    canvas_commit();
+    oled_blit();
 #ifndef TESTING
     if (duration > 0) delay_ms(duration);
 #endif
@@ -79,16 +80,14 @@ void screen_print_debug_hex(const uint8_t* bytes, size_t len, int duration)
 // Careful, this function is used in both the bootloader and the firmware.
 void screen_splash(void)
 {
-    screen_clear();
-
     int height = IMAGE_DEFAULT_ARROW_HEIGHT;
     int x = 0;
     int y = SCREEN_HEIGHT / 2 - height;
     image_arrow(x - height + 2, y, height, ARROW_RIGHT);
     image_arrow(SCREEN_WIDTH - x - 2, y, height, ARROW_LEFT);
 
-    UG_SendBuffer();
-    screen_clear();
+    canvas_commit();
+    oled_blit();
 }
 
 void screen_rotate(void)
@@ -105,18 +104,8 @@ bool screen_is_upside_down(void)
     return screen_upside_down;
 }
 
-void screen_init(
-    void (*pixel_fn)(UG_S16, UG_S16, UG_COLOR),
-    void (*mirror_fn)(bool),
-    void (*clear_fn)(void))
+void screen_init(void (*pixel_fn)(UG_S16, UG_S16, UG_COLOR), void (*mirror_fn)(bool))
 {
     _mirror_fn = mirror_fn;
-    _clear_fn = clear_fn;
     UG_Init(&guioled, pixel_fn, &font_font_a_11X10, SCREEN_WIDTH, SCREEN_HEIGHT);
 }
-
-void screen_clear(void)
-{
-    ASSERT(_clear_fn);
-    _clear_fn();
-}