[Core] Add Raspberry Pi RP2040 support (qmk#14877)

* Disable RESET keycode because of naming conflicts

* Add Pico SDK as submodule

* Add RP2040 build support to QMK

* Adjust USB endpoint structs for RP2040

* Add RP2040 bootloader and double-tap reset routine

* Add generic and pro micro RP2040 boards

* Add RP2040 onekey keyboard

* Add WS2812 PIO DMA enabled driver and documentation

Supports regular and open-drain output configuration. RP2040 GPIOs are
sadly not 5V tolerant, so this is a bit use-less or needs extra hardware
or you take the risk to fry your hardware.

* Adjust SIO Driver for RP2040

* Adjust I2C Driver for RP2040

* Adjust SPI Driver for RP2040

* Add PIO serial driver and documentation

* Add general RP2040 documentation

* Apply suggestions from code review

Co-authored-by: Nick Brassel <nick@tzarc.org>

Co-authored-by: Nick Brassel <nick@tzarc.org>

Author: KarlK90

.gitmodules

@@ -18,3 +18,6 @@
 [submodule "lib/printf"]
 	path = lib/printf
 	url = https://github.com/qmk/printf
+[submodule "lib/pico-sdk"]
+	path = lib/pico-sdk
+	url = https://github.com/qmk/pico-sdk.git

Makefile

@@ -401,6 +401,7 @@ ifndef SKIP_GIT
 	if [ ! -e lib/lufa ]; then git submodule sync lib/lufa && git submodule update --depth 50 --init lib/lufa; fi
 	if [ ! -e lib/vusb ]; then git submodule sync lib/vusb && git submodule update --depth 50 --init lib/vusb; fi
 	if [ ! -e lib/printf ]; then git submodule sync lib/printf && git submodule update --depth 50 --init lib/printf; fi
+	if [ ! -e lib/pico-sdk ]; then git submodule sync lib/pico-sdk && git submodule update --depth 50 --init lib/pico-sdk; fi
 	git submodule status --recursive 2>/dev/null | \
 	while IFS= read -r x; do \
 		case "$$x" in \

builddefs/bootloader.mk

@@ -200,6 +200,10 @@ ifeq ($(strip $(BOOTLOADER)), tinyuf2)
     OPT_DEFS += -DBOOTLOADER_TINYUF2
     BOOTLOADER_TYPE = tinyuf2
 endif
+ifeq ($(strip $(BOOTLOADER)), rp2040)
+    OPT_DEFS += -DBOOTLOADER_RP2040
+    BOOTLOADER_TYPE = rp2040
+endif
 ifeq ($(strip $(BOOTLOADER)), halfkay)
     OPT_DEFS += -DBOOTLOADER_HALFKAY
     BOOTLOADER_TYPE = halfkay

builddefs/common_features.mk

@@ -547,7 +547,7 @@ ifeq ($(strip $(BACKLIGHT_ENABLE)), yes)
     endif
 endif
 
-VALID_WS2812_DRIVER_TYPES := bitbang pwm spi i2c
+VALID_WS2812_DRIVER_TYPES := bitbang pwm spi i2c vendor
 
 WS2812_DRIVER ?= bitbang
 ifeq ($(strip $(WS2812_DRIVER_REQUIRED)), yes)
@@ -637,7 +637,7 @@ ifneq ($(strip $(DEBOUNCE_TYPE)), custom)
 endif
 
 
-VALID_SERIAL_DRIVER_TYPES := bitbang usart
+VALID_SERIAL_DRIVER_TYPES := bitbang usart vendor
 
 SERIAL_DRIVER ?= bitbang
 ifeq ($(filter $(SERIAL_DRIVER),$(VALID_SERIAL_DRIVER_TYPES)),)

builddefs/mcu_selection.mk

@@ -116,6 +116,41 @@ ifneq ($(findstring MK66FX1M0, $(MCU)),)
   BOARD ?= PJRC_TEENSY_3_6
 endif
 
+ifneq ($(findstring RP2040, $(MCU)),)
+  # Cortex version
+  MCU = cortex-m0plus
+
+  # ARM version, CORTEX-M0/M1 are 6, CORTEX-M3/M4/M7 are 7
+  CHIBIOS_PORT = ARMv6-M-RP2
+
+  ## chip/board settings
+  # - the next two should match the directories in
+  #   <chibios[-contrib]>/os/hal/ports/$(MCU_PORT_NAME)/$(MCU_SERIES)
+  #   OR
+  #   <chibios[-contrib]>/os/hal/ports/$(MCU_FAMILY)/$(MCU_SERIES)
+  MCU_FAMILY = RP
+  MCU_SERIES = RP2040
+
+  # Linker script to use
+  # - it should exist either in <chibios>/os/common/ports/ARMCMx/compilers/GCC/ld/
+  #   or <keyboard_dir>/ld/
+  STARTUPLD_CONTRIB = $(CHIBIOS_CONTRIB)/os/common/startup/ARMCMx/compilers/GCC/ld
+  MCU_LDSCRIPT ?= RP2040_FLASH
+  LDFLAGS += -L $(STARTUPLD_CONTRIB)
+
+  # Startup code to use
+  #  - it should exist in <chibios>/os/common/startup/ARMCMx/compilers/GCC/mk/
+  MCU_STARTUP ?= rp2040
+
+  # Board: it should exist either in <chibios>/os/hal/boards/,
+  # <keyboard_dir>/boards/, or drivers/boards/
+  BOARD ?= GENERIC_PROMICRO_RP2040
+
+  # Default UF2 Bootloader settings
+  UF2_FAMILY ?= RP2040
+  FIRMWARE_FORMAT ?= uf2
+endif
+
 ifneq ($(findstring STM32F042, $(MCU)),)
   # Cortex version
   MCU = cortex-m0

data/schemas/definitions.jsonschema

@@ -101,6 +101,10 @@
                 "type": "string",
                 "pattern": "^LINE_PIN\\d{1,2}$"
             },
+            {
+                "type": "string",
+                "pattern": "^GP\\d{1,2}$"
+            },
             {
                 "type": "integer"
             },

data/schemas/keyboard.jsonschema

@@ -42,7 +42,7 @@
         },
         "processor": {
             "type": "string",
-            "enum": ["cortex-m0", "cortex-m0plus", "cortex-m3", "cortex-m4", "MKL26Z64", "MK20DX128", "MK20DX256", "MK66FX1M0", "STM32F042", "STM32F072", "STM32F103", "STM32F303", "STM32F401", "STM32F405", "STM32F407", "STM32F411", "STM32F446", "STM32G431", "STM32G474", "STM32L412", "STM32L422", "STM32L432", "STM32L433", "STM32L442", "STM32L443", "GD32VF103", "WB32F3G71", "WB32FQ95", "atmega16u2", "atmega32u2", "atmega16u4", "atmega32u4", "at90usb162", "at90usb646", "at90usb647", "at90usb1286", "at90usb1287", "atmega32a", "atmega328p", "atmega328", "attiny85", "unknown"]
+            "enum": ["cortex-m0", "cortex-m0plus", "cortex-m3", "cortex-m4", "MKL26Z64", "MK20DX128", "MK20DX256", "MK66FX1M0", "RP2040", "STM32F042", "STM32F072", "STM32F103", "STM32F303", "STM32F401", "STM32F405", "STM32F407", "STM32F411", "STM32F446", "STM32G431", "STM32G474", "STM32L412", "STM32L422", "STM32L432", "STM32L433", "STM32L442", "STM32L443", "GD32VF103", "WB32F3G71", "WB32FQ95", "atmega16u2", "atmega32u2", "atmega16u4", "atmega32u4", "at90usb162", "at90usb646", "at90usb647", "at90usb1286", "at90usb1287", "atmega32a", "atmega328p", "atmega328", "attiny85", "unknown"]
         },
         "audio": {
             "type": "object",
@@ -86,7 +86,7 @@
         },
         "bootloader": {
             "type": "string",
-            "enum": ["atmel-dfu", "bootloadhid", "bootloadHID", "custom", "caterina", "halfkay", "kiibohd", "lufa-dfu", "lufa-ms", "md-boot", "qmk-dfu", "qmk-hid", "stm32-dfu", "stm32duino", "gd32v-dfu", "wb32-dfu", "unknown", "usbasploader", "USBasp", "tinyuf2"],
+            "enum": ["atmel-dfu", "bootloadhid", "bootloadHID", "custom", "caterina", "halfkay", "kiibohd", "lufa-dfu", "lufa-ms", "md-boot", "qmk-dfu", "qmk-hid", "stm32-dfu", "stm32duino", "gd32v-dfu", "wb32-dfu", "unknown", "usbasploader", "USBasp", "tinyuf2", "rp2040"],
         },
         "bootloader_instructions": {
             "type": "string",

docs/_summary.md

@@ -165,6 +165,7 @@
     * Arm/ChibiOS
       * [Selecting an MCU](platformdev_selecting_arm_mcu.md)
       * [Early initialization](platformdev_chibios_earlyinit.md)
+      * [Raspberry Pi RP2040](platformdev_rp2040.md)
 
   * QMK Reference
     * [Contributing to QMK](contributing.md)

docs/compatible_microcontrollers.md

@@ -65,6 +65,12 @@ You can also use any ARM chip with USB that [ChibiOS](https://www.chibios.org) s
  * [MK66FX1M0](https://www.nxp.com/products/processors-and-microcontrollers/arm-microcontrollers/general-purpose-mcus/k-series-cortex-m4/k6x-ethernet/kinetis-k66-180-mhz-dual-high-speed-full-speed-usbs-2mb-flash-microcontrollers-mcus-based-on-arm-cortex-m4-core:K66_180)
    * PJRC Teensy 3.6
 
+### Raspberry Pi
+
+* [RP2040](https://www.raspberrypi.com/documentation/microcontrollers/rp2040.html)
+
+For a detailed overview about the RP2040 support by QMK see the [dedicated RP2040 page](platformdev_rp2040.md).
+
 ## Atmel ATSAM
 
 There is limited support for one of Atmel's ATSAM microcontrollers, that being the [ATSAMD51J18A](https://www.microchip.com/wwwproducts/en/ATSAMD51J18A) used by the [Massdrop keyboards](https://github.com/qmk/qmk_firmware/tree/master/keyboards/massdrop). However, it is not recommended to design a board with this microcontroller as the support is quite specialized to Massdrop hardware.

docs/flashing.md

@@ -362,3 +362,42 @@ CLI Flashing sequence:
 ### `make` Targets
 
 * `:uf2-split-left` and `:uf2-split-right`: Flashes the firmware but also sets the handedness setting in EEPROM by generating a side specific firmware.
+
+## Raspberry Pi RP2040 UF2
+
+The `rules.mk` setting for this bootloader is `rp2040`, and can be specified at the keymap or user level.
+
+To ensure compatibility with the rp2040 bootloader, make sure this block is present in your `rules.mk`:
+
+```make
+# Bootloader selection
+BOOTLOADER = rp2040
+```
+
+Compatible flashers:
+
+* Any application able to copy a file from one place to another, such as _macOS Finder_ or _Windows Explorer_.
+
+Flashing sequence:
+
+1. Enter the bootloader using any of the following methods:
+    * Tap the `QK_BOOTLOADER` keycode
+    * Hold the `BOOTSEL` button on the PCB while plugin in the usb cable.
+    * Double-tap the `RESET` button on the PCB<sup>1</sup>.
+2. Wait for the OS to detect the device
+3. Copy the .uf2 file to the new USB disk
+4. Wait for the keyboard to become available
+
+or
+
+CLI Flashing sequence:
+
+1. Enter the bootloader using any of the following methods:
+    * Tap the `QK_BOOTLOADER` keycode
+    * Hold the `BOOTSEL` button on the PCB while plugin in the usb cable.
+    * Double-tap the `RESET` button on the PCB<sup>1</sup>.
+2. Wait for the OS to detect the device
+3. Flash via QMK CLI eg. `qmk flash --keyboard handwired/onekey/rpi_pico --keymap default`
+4. Wait for the keyboard to become available
+
+<sup>1</sup>: This works only if QMK was compiled with `RP2040_BOOTLOADER_DOUBLE_TAP_RESET` defined.