Move tmk_core/common/<plat> (#13918)

19 files changed, 1905 insertions, 0 deletions

diff --git a/platforms/avr/_print.h b/platforms/avr/_print.h
new file mode 100644
index 0000000000..5c1fdd26d8
--- /dev/null
+++ b/platforms/avr/_print.h
@@ -0,0 +1,33 @@
+/* Copyright 2012 Jun Wako <wakojun@gmail.com> */
+/* Very basic print functions, intended to be used with usb_debug_only.c
+ * http://www.pjrc.com/teensy/
+ * Copyright (c) 2008 PJRC.COM, LLC
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+#pragma once
+
+#include "avr/xprintf.h"
+
+// Create user & normal print defines
+#define print(s) xputs(PSTR(s))
+#define println(s) xputs(PSTR(s "\r\n"))
+#define uprint(s) xputs(PSTR(s))
+#define uprintln(s) xputs(PSTR(s "\r\n"))
+#define uprintf(fmt, ...) __xprintf(PSTR(fmt), ##__VA_ARGS__)
\ No newline at end of file
diff --git a/platforms/avr/_timer.h b/platforms/avr/_timer.h
new file mode 100644
index 0000000000..b81e0f68b7
--- /dev/null
+++ b/platforms/avr/_timer.h
@@ -0,0 +1,19 @@
+/* Copyright 2021 Simon Arlott
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+#pragma once
+
+// The platform is 8-bit, so prefer 16-bit timers to reduce code size
+#define FAST_TIMER_T_SIZE 16
diff --git a/platforms/avr/_wait.h b/platforms/avr/_wait.h
new file mode 100644
index 0000000000..683db6ae57
--- /dev/null
+++ b/platforms/avr/_wait.h
@@ -0,0 +1,49 @@
+/* Copyright 2021 QMK
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+#pragma once
+
+#include <util/delay.h>
+
+#define wait_ms(ms)                             \
+    do {                                        \
+        if (__builtin_constant_p(ms)) {         \
+            _delay_ms(ms);                      \
+        } else {                                \
+            for (uint16_t i = ms; i > 0; i--) { \
+                _delay_ms(1);                   \
+            }                                   \
+        }                                       \
+    } while (0)
+#define wait_us(us)                             \
+    do {                                        \
+        if (__builtin_constant_p(us)) {         \
+            _delay_us(us);                      \
+        } else {                                \
+            for (uint16_t i = us; i > 0; i--) { \
+                _delay_us(1);                   \
+            }                                   \
+        }                                       \
+    } while (0)
+#define wait_cpuclock(n) __builtin_avr_delay_cycles(n)
+#define CPU_CLOCK F_CPU
+
+/* The AVR series GPIOs have a one clock read delay for changes in the digital input signal.
+ * But here's more margin to make it two clocks. */
+#ifndef GPIO_INPUT_PIN_DELAY
+#    define GPIO_INPUT_PIN_DELAY 2
+#endif
+
+#define waitInputPinDelay() wait_cpuclock(GPIO_INPUT_PIN_DELAY)
diff --git a/platforms/avr/atomic_util.h b/platforms/avr/atomic_util.h
new file mode 100644
index 0000000000..7c5d2e7dcc
--- /dev/null
+++ b/platforms/avr/atomic_util.h
@@ -0,0 +1,22 @@
+/* Copyright 2021 QMK
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+#pragma once
+
+/* atomic macro for AVR */
+#include <util/atomic.h>
+
+#define ATOMIC_BLOCK_RESTORESTATE ATOMIC_BLOCK(ATOMIC_RESTORESTATE)
+#define ATOMIC_BLOCK_FORCEON ATOMIC_BLOCK(ATOMIC_FORCEON)
diff --git a/platforms/avr/bootloader.c b/platforms/avr/bootloader.c
new file mode 100644
index 0000000000..c0272903b8
--- /dev/null
+++ b/platforms/avr/bootloader.c
@@ -0,0 +1,293 @@
+#include <stdint.h>
+#include <stdbool.h>
+#include <avr/io.h>
+#include <avr/eeprom.h>
+#include <avr/interrupt.h>
+#include <avr/wdt.h>
+#include <util/delay.h>
+#include "bootloader.h"
+#include <avr/boot.h>
+
+#ifdef PROTOCOL_LUFA
+#    include <LUFA/Drivers/USB/USB.h>
+#endif
+
+/** \brief Bootloader Size in *bytes*
+ *
+ * AVR Boot section size are defined by setting BOOTSZ fuse in fact. Consult with your MCU datasheet.
+ * Note that 'Word'(2 bytes) size and address are used in datasheet while TMK uses 'Byte'.
+ *
+ * Size of Bootloaders in bytes:
+ *   Atmel DFU loader(ATmega32U4)   4096
+ *   Atmel DFU loader(AT90USB128)   8192
+ *   LUFA bootloader(ATmega32U4)    4096
+ *   Arduino Caterina(ATmega32U4)   4096
+ *   USBaspLoader(ATmega***)        2048
+ *   Teensy   halfKay(ATmega32U4)   512
+ *   Teensy++ halfKay(AT90USB128)   1024
+ *
+ * AVR Boot section is located at the end of Flash memory like the followings.
+ *
+ * byte     Atmel/LUFA(ATMega32u4)          byte     Atmel(AT90SUB128)
+ * 0x0000   +---------------+               0x00000  +---------------+
+ *          |               |                        |               |
+ *          |               |                        |               |
+ *          |  Application  |                        |  Application  |
+ *          |               |                        |               |
+ *          =               =                        =               =
+ *          |               | 32KB-4KB               |               | 128KB-8KB
+ * 0x7000   +---------------+               0x1E000  +---------------+
+ *          |  Bootloader   | 4KB                    |  Bootloader   | 8KB
+ * 0x7FFF   +---------------+               0x1FFFF  +---------------+
+ *
+ *
+ * byte     Teensy(ATMega32u4)              byte     Teensy++(AT90SUB128)
+ * 0x0000   +---------------+               0x00000  +---------------+
+ *          |               |                        |               |
+ *          |               |                        |               |
+ *          |  Application  |                        |  Application  |
+ *          |               |                        |               |
+ *          =               =                        =               =
+ *          |               | 32KB-512B              |               | 128KB-1KB
+ * 0x7E00   +---------------+               0x1FC00  +---------------+
+ *          |  Bootloader   | 512B                   |  Bootloader   | 1KB
+ * 0x7FFF   +---------------+               0x1FFFF  +---------------+
+ */
+#define FLASH_SIZE (FLASHEND + 1L)
+
+#if !defined(BOOTLOADER_SIZE)
+uint16_t bootloader_start;
+#endif
+
+// compatibility between ATMega8 and ATMega88
+#if !defined(MCUCSR)
+#    if defined(MCUSR)
+#        define MCUCSR MCUSR
+#    endif
+#endif
+
+/** \brief Entering the Bootloader via Software
+ *
+ * http://www.fourwalledcubicle.com/files/LUFA/Doc/120730/html/_page__software_bootloader_start.html
+ */
+#define BOOTLOADER_RESET_KEY 0xB007B007
+uint32_t reset_key __attribute__((section(".noinit,\"aw\",@nobits;")));
+
+/** \brief initialize MCU status by watchdog reset
+ *
+ * FIXME: needs doc
+ */
+__attribute__((weak)) void bootloader_jump(void) {
+#if !defined(BOOTLOADER_SIZE)
+    uint8_t high_fuse = boot_lock_fuse_bits_get(GET_HIGH_FUSE_BITS);
+
+    if (high_fuse & ~(FUSE_BOOTSZ0 & FUSE_BOOTSZ1)) {
+        bootloader_start = (FLASH_SIZE - 512) >> 1;
+    } else if (high_fuse & ~(FUSE_BOOTSZ1)) {
+        bootloader_start = (FLASH_SIZE - 1024) >> 1;
+    } else if (high_fuse & ~(FUSE_BOOTSZ0)) {
+        bootloader_start = (FLASH_SIZE - 2048) >> 1;
+    } else {
+        bootloader_start = (FLASH_SIZE - 4096) >> 1;
+    }
+#endif
+
+    // Something like this might work, but it compiled larger than the block above
+    // bootloader_start = FLASH_SIZE - (256 << (~high_fuse & 0b110 >> 1));
+
+#if defined(BOOTLOADER_HALFKAY)
+    //  http://www.pjrc.com/teensy/jump_to_bootloader.html
+    cli();
+    // disable watchdog, if enabled (it's not)
+    // disable all peripherals
+    // a shutdown call might make sense here
+    UDCON  = 1;
+    USBCON = (1 << FRZCLK);  // disable USB
+    UCSR1B = 0;
+    _delay_ms(5);
+#    if defined(__AVR_AT90USB162__)  // Teensy 1.0
+    EIMSK  = 0;
+    PCICR  = 0;
+    SPCR   = 0;
+    ACSR   = 0;
+    EECR   = 0;
+    TIMSK0 = 0;
+    TIMSK1 = 0;
+    UCSR1B = 0;
+    DDRB   = 0;
+    DDRC   = 0;
+    DDRD   = 0;
+    PORTB  = 0;
+    PORTC  = 0;
+    PORTD  = 0;
+    asm volatile("jmp 0x3E00");
+#    elif defined(__AVR_ATmega32U4__)   // Teensy 2.0
+    EIMSK  = 0;
+    PCICR  = 0;
+    SPCR   = 0;
+    ACSR   = 0;
+    EECR   = 0;
+    ADCSRA = 0;
+    TIMSK0 = 0;
+    TIMSK1 = 0;
+    TIMSK3 = 0;
+    TIMSK4 = 0;
+    UCSR1B = 0;
+    TWCR   = 0;
+    DDRB   = 0;
+    DDRC   = 0;
+    DDRD   = 0;
+    DDRE   = 0;
+    DDRF   = 0;
+    TWCR   = 0;
+    PORTB  = 0;
+    PORTC  = 0;
+    PORTD  = 0;
+    PORTE  = 0;
+    PORTF  = 0;
+    asm volatile("jmp 0x7E00");
+#    elif defined(__AVR_AT90USB646__)   // Teensy++ 1.0
+    EIMSK  = 0;
+    PCICR  = 0;
+    SPCR   = 0;
+    ACSR   = 0;
+    EECR   = 0;
+    ADCSRA = 0;
+    TIMSK0 = 0;
+    TIMSK1 = 0;
+    TIMSK2 = 0;
+    TIMSK3 = 0;
+    UCSR1B = 0;
+    TWCR   = 0;
+    DDRA   = 0;
+    DDRB   = 0;
+    DDRC   = 0;
+    DDRD   = 0;
+    DDRE   = 0;
+    DDRF   = 0;
+    PORTA  = 0;
+    PORTB  = 0;
+    PORTC  = 0;
+    PORTD  = 0;
+    PORTE  = 0;
+    PORTF  = 0;
+    asm volatile("jmp 0xFC00");
+#    elif defined(__AVR_AT90USB1286__)  // Teensy++ 2.0
+    EIMSK  = 0;
+    PCICR  = 0;
+    SPCR   = 0;
+    ACSR   = 0;
+    EECR   = 0;
+    ADCSRA = 0;
+    TIMSK0 = 0;
+    TIMSK1 = 0;
+    TIMSK2 = 0;
+    TIMSK3 = 0;
+    UCSR1B = 0;
+    TWCR   = 0;
+    DDRA   = 0;
+    DDRB   = 0;
+    DDRC   = 0;
+    DDRD   = 0;
+    DDRE   = 0;
+    DDRF   = 0;
+    PORTA  = 0;
+    PORTB  = 0;
+    PORTC  = 0;
+    PORTD  = 0;
+    PORTE  = 0;
+    PORTF  = 0;
+    asm volatile("jmp 0x1FC00");
+#    endif
+
+#elif defined(BOOTLOADER_CATERINA)
+    // this block may be optional
+    // TODO: figure it out
+
+    uint16_t *const bootKeyPtr = (uint16_t *)0x0800;
+
+    // Value used by Caterina bootloader use to determine whether to run the
+    // sketch or the bootloader programmer.
+    uint16_t bootKey = 0x7777;
+
+    *bootKeyPtr = bootKey;
+
+    // setup watchdog timeout
+    wdt_enable(WDTO_60MS);
+
+    while (1) {
+    }  // wait for watchdog timer to trigger
+
+#elif defined(BOOTLOADER_USBASP)
+    // Taken with permission of Stephan Baerwolf from https://github.com/tinyusbboard/API/blob/master/apipage.c
+    wdt_enable(WDTO_15MS);
+    wdt_reset();
+    asm volatile("cli                    \n\t"
+                 "ldi    r29 ,       %[ramendhi] \n\t"
+                 "ldi    r28 ,       %[ramendlo] \n\t"
+#    if (FLASHEND > 131071)
+                 "ldi    r18 ,       %[bootaddrhi]   \n\t"
+                 "st     Y+,         r18     \n\t"
+#    endif
+                 "ldi    r18 ,       %[bootaddrme]   \n\t"
+                 "st     Y+,     r18     \n\t"
+                 "ldi    r18 ,       %[bootaddrlo]   \n\t"
+                 "st     Y+,     r18     \n\t"
+                 "out    %[mcucsrio],    __zero_reg__    \n\t"
+                 "bootloader_startup_loop%=:         \n\t"
+                 "rjmp bootloader_startup_loop%=     \n\t"
+                 :
+                 : [mcucsrio] "I"(_SFR_IO_ADDR(MCUCSR)),
+#    if (FLASHEND > 131071)
+                   [ramendhi] "M"(((RAMEND - 2) >> 8) & 0xff), [ramendlo] "M"(((RAMEND - 2) >> 0) & 0xff), [bootaddrhi] "M"((((FLASH_SIZE - BOOTLOADER_SIZE) >> 1) >> 16) & 0xff),
+#    else
+                   [ramendhi] "M"(((RAMEND - 1) >> 8) & 0xff), [ramendlo] "M"(((RAMEND - 1) >> 0) & 0xff),
+#    endif
+                   [bootaddrme] "M"((((FLASH_SIZE - BOOTLOADER_SIZE) >> 1) >> 8) & 0xff), [bootaddrlo] "M"((((FLASH_SIZE - BOOTLOADER_SIZE) >> 1) >> 0) & 0xff));
+
+#else  // Assume remaining boards are DFU, even if the flag isn't set
+
+#    if !(defined(__AVR_ATmega32A__) || defined(__AVR_ATmega328P__) || defined(__AVR_ATmega328__) || defined(__AVR_ATtiny85__))  // no USB - maybe BOOTLOADER_BOOTLOADHID instead though?
+    UDCON  = 1;
+    USBCON = (1 << FRZCLK);  // disable USB
+    UCSR1B = 0;
+    _delay_ms(5);  // 5 seems to work fine
+#    endif
+
+#    ifdef BOOTLOADER_BOOTLOADHID
+    // force bootloadHID to stay in bootloader mode, so that it waits
+    // for a new firmware to be flashed
+    eeprom_write_byte((uint8_t *)1, 0x00);
+#    endif
+
+    // watchdog reset
+    reset_key = BOOTLOADER_RESET_KEY;
+    wdt_enable(WDTO_250MS);
+    for (;;)
+        ;
+#endif
+}
+
+/* this runs before main() */
+void bootloader_jump_after_watchdog_reset(void) __attribute__((used, naked, section(".init3")));
+void bootloader_jump_after_watchdog_reset(void) {
+#ifndef BOOTLOADER_HALFKAY
+    if ((MCUCSR & (1 << WDRF)) && reset_key == BOOTLOADER_RESET_KEY) {
+        reset_key = 0;
+
+        // My custom USBasploader requires this to come up.
+        MCUCSR = 0;
+
+        // Seems like Teensy halfkay loader requires clearing WDRF and disabling watchdog.
+        MCUCSR &= ~(1 << WDRF);
+        wdt_disable();
+
+// This is compled into 'icall', address should be in word unit, not byte.
+#    ifdef BOOTLOADER_SIZE
+        ((void (*)(void))((FLASH_SIZE - BOOTLOADER_SIZE) >> 1))();
+#    else
+        asm("ijmp" ::"z"(bootloader_start));
+#    endif
+    }
+#endif
+}
diff --git a/platforms/avr/bootloader_size.c b/platforms/avr/bootloader_size.c
new file mode 100644
index 0000000000..a029f9321f
--- /dev/null
+++ b/platforms/avr/bootloader_size.c
@@ -0,0 +1,21 @@
+// Copyright 2017 Jack Humbert
+//
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 2 of the License, or
+// (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+#include <avr/io.h>
+#include <avr/boot.h>
+
+// clang-format off
+// this is not valid C - it's for computing the size available on the chip
+AVR_SIZE: FLASHEND + 1 - BOOTLOADER_SIZE
diff --git a/platforms/avr/gpio.h b/platforms/avr/gpio.h
new file mode 100644
index 0000000000..e9be68491d
--- /dev/null
+++ b/platforms/avr/gpio.h
@@ -0,0 +1,49 @@
+/* Copyright 2021 QMK
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+#pragma once
+
+#include <avr/io.h>
+#include "pin_defs.h"
+
+typedef uint8_t pin_t;
+
+/* Operation of GPIO by pin. */
+
+#define setPinInput(pin) (DDRx_ADDRESS(pin) &= ~_BV((pin)&0xF), PORTx_ADDRESS(pin) &= ~_BV((pin)&0xF))
+#define setPinInputHigh(pin) (DDRx_ADDRESS(pin) &= ~_BV((pin)&0xF), PORTx_ADDRESS(pin) |= _BV((pin)&0xF))
+#define setPinInputLow(pin) _Static_assert(0, "AVR processors cannot implement an input as pull low")
+#define setPinOutput(pin) (DDRx_ADDRESS(pin) |= _BV((pin)&0xF))
+
+#define writePinHigh(pin) (PORTx_ADDRESS(pin) |= _BV((pin)&0xF))
+#define writePinLow(pin) (PORTx_ADDRESS(pin) &= ~_BV((pin)&0xF))
+#define writePin(pin, level) ((level) ? writePinHigh(pin) : writePinLow(pin))
+
+#define readPin(pin) ((bool)(PINx_ADDRESS(pin) & _BV((pin)&0xF)))
+
+#define togglePin(pin) (PORTx_ADDRESS(pin) ^= _BV((pin)&0xF))
+
+/* Operation of GPIO by port. */
+
+typedef uint8_t port_data_t;
+
+#define readPort(port) PINx_ADDRESS(port)
+
+#define setPortBitInput(port, bit) (DDRx_ADDRESS(port) &= ~_BV((bit)&0xF), PORTx_ADDRESS(port) &= ~_BV((bit)&0xF))
+#define setPortBitInputHigh(port, bit) (DDRx_ADDRESS(port) &= ~_BV((bit)&0xF), PORTx_ADDRESS(port) |= _BV((bit)&0xF))
+#define setPortBitOutput(port, bit) (DDRx_ADDRESS(port) |= _BV((bit)&0xF))
+
+#define writePortBitLow(port, bit) (PORTx_ADDRESS(port) &= ~_BV((bit)&0xF))
+#define writePortBitHigh(port, bit) (PORTx_ADDRESS(port) |= _BV((bit)&0xF))
diff --git a/platforms/avr/pin_defs.h b/platforms/avr/pin_defs.h
new file mode 100644
index 0000000000..23d948041d
--- /dev/null
+++ b/platforms/avr/pin_defs.h
@@ -0,0 +1,128 @@
+/* Copyright 2021 QMK
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+#pragma once
+
+#include <avr/io.h>
+
+#define PORT_SHIFTER 4  // this may be 4 for all AVR chips
+
+// If you want to add more to this list, reference the PINx definitions in these header
+// files: https://github.com/vancegroup-mirrors/avr-libc/tree/master/avr-libc/include/avr
+
+#if defined(__AVR_ATmega32U4__) || defined(__AVR_ATmega16U4__)
+#    define ADDRESS_BASE 0x00
+#    define PINB_ADDRESS 0x3
+#    define PINC_ADDRESS 0x6
+#    define PIND_ADDRESS 0x9
+#    define PINE_ADDRESS 0xC
+#    define PINF_ADDRESS 0xF
+#elif defined(__AVR_AT90USB162__) || defined(__AVR_ATmega32U2__) || defined(__AVR_ATmega16U2__) || defined(__AVR_ATmega328P__) || defined(__AVR_ATmega328__)
+#    define ADDRESS_BASE 0x00
+#    define PINB_ADDRESS 0x3
+#    define PINC_ADDRESS 0x6
+#    define PIND_ADDRESS 0x9
+#elif defined(__AVR_AT90USB646__) || defined(__AVR_AT90USB647__) || defined(__AVR_AT90USB1286__) || defined(__AVR_AT90USB1287__)
+#    define ADDRESS_BASE 0x00
+#    define PINA_ADDRESS 0x0
+#    define PINB_ADDRESS 0x3
+#    define PINC_ADDRESS 0x6
+#    define PIND_ADDRESS 0x9
+#    define PINE_ADDRESS 0xC
+#    define PINF_ADDRESS 0xF
+#elif defined(__AVR_ATmega32A__)
+#    define ADDRESS_BASE 0x10
+#    define PIND_ADDRESS 0x0
+#    define PINC_ADDRESS 0x3
+#    define PINB_ADDRESS 0x6
+#    define PINA_ADDRESS 0x9
+#elif defined(__AVR_ATtiny85__)
+#    define ADDRESS_BASE 0x10
+#    define PINB_ADDRESS 0x6
+#else
+#    error "Pins are not defined"
+#endif
+
+#define PINDEF(port, pin) ((PIN##port##_ADDRESS << PORT_SHIFTER) | pin)
+
+#define _PIN_ADDRESS(p, offset) _SFR_IO8(ADDRESS_BASE + ((p) >> PORT_SHIFTER) + (offset))
+// Port X Input Pins Address
+#define PINx_ADDRESS(p) _PIN_ADDRESS(p, 0)
+// Port X Data Direction Register,  0:input 1:output
+#define DDRx_ADDRESS(p) _PIN_ADDRESS(p, 1)
+// Port X Data Register
+#define PORTx_ADDRESS(p) _PIN_ADDRESS(p, 2)
+
+/* I/O pins */
+#ifdef PORTA
+#    define A0 PINDEF(A, 0)
+#    define A1 PINDEF(A, 1)
+#    define A2 PINDEF(A, 2)
+#    define A3 PINDEF(A, 3)
+#    define A4 PINDEF(A, 4)
+#    define A5 PINDEF(A, 5)
+#    define A6 PINDEF(A, 6)
+#    define A7 PINDEF(A, 7)
+#endif
+#ifdef PORTB
+#    define B0 PINDEF(B, 0)
+#    define B1 PINDEF(B, 1)
+#    define B2 PINDEF(B, 2)
+#    define B3 PINDEF(B, 3)
+#    define B4 PINDEF(B, 4)
+#    define B5 PINDEF(B, 5)
+#    define B6 PINDEF(B, 6)
+#    define B7 PINDEF(B, 7)
+#endif
+#ifdef PORTC
+#    define C0 PINDEF(C, 0)
+#    define C1 PINDEF(C, 1)
+#    define C2 PINDEF(C, 2)
+#    define C3 PINDEF(C, 3)
+#    define C4 PINDEF(C, 4)
+#    define C5 PINDEF(C, 5)
+#    define C6 PINDEF(C, 6)
+#    define C7 PINDEF(C, 7)
+#endif
+#ifdef PORTD
+#    define D0 PINDEF(D, 0)
+#    define D1 PINDEF(D, 1)
+#    define D2 PINDEF(D, 2)
+#    define D3 PINDEF(D, 3)
+#    define D4 PINDEF(D, 4)
+#    define D5 PINDEF(D, 5)
+#    define D6 PINDEF(D, 6)
+#    define D7 PINDEF(D, 7)
+#endif
+#ifdef PORTE
+#    define E0 PINDEF(E, 0)
+#    define E1 PINDEF(E, 1)
+#    define E2 PINDEF(E, 2)
+#    define E3 PINDEF(E, 3)
+#    define E4 PINDEF(E, 4)
+#    define E5 PINDEF(E, 5)
+#    define E6 PINDEF(E, 6)
+#    define E7 PINDEF(E, 7)
+#endif
+#ifdef PORTF
+#    define F0 PINDEF(F, 0)
+#    define F1 PINDEF(F, 1)
+#    define F2 PINDEF(F, 2)
+#    define F3 PINDEF(F, 3)
+#    define F4 PINDEF(F, 4)
+#    define F5 PINDEF(F, 5)
+#    define F6 PINDEF(F, 6)
+#    define F7 PINDEF(F, 7)
+#endif
diff --git a/platforms/avr/platform.c b/platforms/avr/platform.c
new file mode 100644
index 0000000000..3e35b4fe4c
--- /dev/null
+++ b/platforms/avr/platform.c
@@ -0,0 +1,21 @@
+/* Copyright 2021 QMK
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "platform_deps.h"
+
+void platform_setup(void) {
+    // do nothing
+}
diff --git a/platforms/avr/platform.mk b/platforms/avr/platform.mk
new file mode 100644
index 0000000000..b45108736f
--- /dev/null
+++ b/platforms/avr/platform.mk
@@ -0,0 +1,179 @@
+# Hey Emacs, this is a -*- makefile -*-
+##############################################################################
+# Compiler settings
+#
+CC = $(CC_PREFIX) avr-gcc
+OBJCOPY = avr-objcopy
+OBJDUMP = avr-objdump
+SIZE = avr-size
+AR = avr-ar
+NM = avr-nm
+HEX = $(OBJCOPY) -O $(FORMAT) -R .eeprom -R .fuse -R .lock -R .signature
+EEP = $(OBJCOPY) -j .eeprom --set-section-flags=.eeprom="alloc,load" --change-section-lma .eeprom=0 --no-change-warnings -O $(FORMAT)
+BIN =
+
+COMPILEFLAGS += -funsigned-char
+COMPILEFLAGS += -funsigned-bitfields
+COMPILEFLAGS += -ffunction-sections
+COMPILEFLAGS += -fdata-sections
+COMPILEFLAGS += -fpack-struct
+COMPILEFLAGS += -fshort-enums
+
+ASFLAGS += $(AVR_ASFLAGS)
+
+CFLAGS += $(COMPILEFLAGS) $(AVR_CFLAGS)
+CFLAGS += -fno-inline-small-functions
+CFLAGS += -fno-strict-aliasing
+
+CXXFLAGS += $(COMPILEFLAGS)
+CXXFLAGS += -fno-exceptions -std=c++11
+
+LDFLAGS +=-Wl,--gc-sections
+
+OPT_DEFS += -DF_CPU=$(F_CPU)UL
+
+MCUFLAGS = -mmcu=$(MCU)
+
+# List any extra directories to look for libraries here.
+#     Each directory must be seperated by a space.
+#     Use forward slashes for directory separators.
+#     For a directory that has spaces, enclose it in quotes.
+EXTRALIBDIRS =
+
+
+#---------------- External Memory Options ----------------
+
+# 64 KB of external RAM, starting after internal RAM (ATmega128!),
+# used for variables (.data/.bss) and heap (malloc()).
+#EXTMEMOPTS = -Wl,-Tdata=0x801100,--defsym=__heap_end=0x80ffff
+
+# 64 KB of external RAM, starting after internal RAM (ATmega128!),
+# only used for heap (malloc()).
+#EXTMEMOPTS = -Wl,--section-start,.data=0x801100,--defsym=__heap_end=0x80ffff
+
+EXTMEMOPTS =
+
+#---------------- Debugging Options ----------------
+
+# Debugging format.
+#     Native formats for AVR-GCC's -g are dwarf-2 [default] or stabs.
+#     AVR Studio 4.10 requires dwarf-2.
+#     AVR [Extended] COFF format requires stabs, plus an avr-objcopy run.
+DEBUG = dwarf-2
+
+# For simulavr only - target MCU frequency.
+DEBUG_MFREQ = $(F_CPU)
+
+# Set the DEBUG_UI to either gdb or insight.
+# DEBUG_UI = gdb
+DEBUG_UI = insight
+
+# Set the debugging back-end to either avarice, simulavr.
+DEBUG_BACKEND = avarice
+#DEBUG_BACKEND = simulavr
+
+# GDB Init Filename.
+GDBINIT_FILE = __avr_gdbinit
+
+# When using avarice settings for the JTAG
+JTAG_DEV = /dev/com1
+
+# Debugging port used to communicate between GDB / avarice / simulavr.
+DEBUG_PORT = 4242
+
+# Debugging host used to communicate between GDB / avarice / simulavr, normally
+#     just set to localhost unless doing some sort of crazy debugging when
+#     avarice is running on a different computer.
+DEBUG_HOST = localhost
+
+#============================================================================
+
+# Convert hex to bin.
+bin: $(BUILD_DIR)/$(TARGET).hex
+ifeq ($(BOOTLOADER),lufa-ms)
+	$(eval BIN_PADDING=$(shell n=`expr 32768 - $(BOOTLOADER_SIZE)` && echo $$(($$n)) || echo 0))
+	$(OBJCOPY) -Iihex -Obinary $(BUILD_DIR)/$(TARGET).hex $(BUILD_DIR)/$(TARGET).bin --pad-to $(BIN_PADDING)
+else
+	$(OBJCOPY) -Iihex -Obinary $(BUILD_DIR)/$(TARGET).hex $(BUILD_DIR)/$(TARGET).bin
+endif
+	$(COPY) $(BUILD_DIR)/$(TARGET).bin $(TARGET).bin;
+
+# copy bin to FLASH.bin
+flashbin: bin
+	$(COPY) $(BUILD_DIR)/$(TARGET).bin FLASH.bin;
+
+# Generate avr-gdb config/init file which does the following:
+#     define the reset signal, load the target file, connect to target, and set
+#     a breakpoint at main().
+gdb-config:
+	@$(REMOVE) $(GDBINIT_FILE)
+	@echo define reset >> $(GDBINIT_FILE)
+	@echo SIGNAL SIGHUP >> $(GDBINIT_FILE)
+	@echo end >> $(GDBINIT_FILE)
+	@echo file $(BUILD_DIR)/$(TARGET).elf >> $(GDBINIT_FILE)
+	@echo target remote $(DEBUG_HOST):$(DEBUG_PORT)  >> $(GDBINIT_FILE)
+ifeq ($(DEBUG_BACKEND),simulavr)
+	@echo load  >> $(GDBINIT_FILE)
+endif
+	@echo break main >> $(GDBINIT_FILE)
+
+debug: gdb-config $(BUILD_DIR)/$(TARGET).elf
+ifeq ($(DEBUG_BACKEND), avarice)
+	@echo Starting AVaRICE - Press enter when "waiting to connect" message displays.
+	@$(WINSHELL) /c start avarice --jtag $(JTAG_DEV) --erase --program --file \
+	$(BUILD_DIR)/$(TARGET).elf $(DEBUG_HOST):$(DEBUG_PORT)
+	@$(WINSHELL) /c pause
+
+else
+	@$(WINSHELL) /c start simulavr --gdbserver --device $(MCU) --clock-freq \
+	$(DEBUG_MFREQ) --port $(DEBUG_PORT)
+endif
+	@$(WINSHELL) /c start avr-$(DEBUG_UI) --command=$(GDBINIT_FILE)
+
+
+
+
+# Convert ELF to COFF for use in debugging / simulating in AVR Studio or VMLAB.
+COFFCONVERT = $(OBJCOPY) --debugging
+COFFCONVERT += --change-section-address .data-0x800000
+COFFCONVERT += --change-section-address .bss-0x800000
+COFFCONVERT += --change-section-address .noinit-0x800000
+COFFCONVERT += --change-section-address .eeprom-0x810000
+
+
+
+coff: $(BUILD_DIR)/$(TARGET).elf
+	@$(SECHO) $(MSG_COFF) $(BUILD_DIR)/$(TARGET).cof
+	$(COFFCONVERT) -O coff-avr $< $(BUILD_DIR)/$(TARGET).cof
+
+
+extcoff: $(BUILD_DIR)/$(TARGET).elf
+	@$(SECHO) $(MSG_EXTENDED_COFF) $(BUILD_DIR)/$(TARGET).cof
+	$(COFFCONVERT) -O coff-ext-avr $< $(BUILD_DIR)/$(TARGET).cof
+
+ifeq ($(strip $(BOOTLOADER)), qmk-dfu)
+QMK_BOOTLOADER_TYPE = DFU
+else ifeq ($(strip $(BOOTLOADER)), qmk-hid)
+QMK_BOOTLOADER_TYPE = HID
+endif
+
+bootloader:
+ifeq ($(strip $(QMK_BOOTLOADER_TYPE)),)
+	$(error Please set BOOTLOADER to "qmk-dfu" or "qmk-hid" first!)
+else
+	make -C lib/lufa/Bootloaders/$(QMK_BOOTLOADER_TYPE)/ clean
+	$(QMK_BIN) generate-dfu-header --quiet --keyboard $(KEYBOARD) --output lib/lufa/Bootloaders/$(QMK_BOOTLOADER_TYPE)/Keyboard.h
+	$(eval MAX_SIZE=$(shell n=`$(CC) -E -mmcu=$(MCU) -D__ASSEMBLER__ $(CFLAGS) $(OPT_DEFS) platforms/avr/bootloader_size.c 2> /dev/null | sed -ne 's/\r//;/^#/n;/^AVR_SIZE:/,$${s/^AVR_SIZE: //;p;}'` && echo $$(($$n)) || echo 0))
+	$(eval PROGRAM_SIZE_KB=$(shell n=`expr $(MAX_SIZE) / 1024` && echo $$(($$n)) || echo 0))
+	$(eval BOOT_SECTION_SIZE_KB=$(shell n=`expr  $(BOOTLOADER_SIZE) / 1024` && echo $$(($$n)) || echo 0))
+	$(eval FLASH_SIZE_KB=$(shell n=`expr $(PROGRAM_SIZE_KB) + $(BOOT_SECTION_SIZE_KB)` && echo $$(($$n)) || echo 0))
+	make -C lib/lufa/Bootloaders/$(QMK_BOOTLOADER_TYPE)/ MCU=$(MCU) ARCH=$(ARCH) F_CPU=$(F_CPU) FLASH_SIZE_KB=$(FLASH_SIZE_KB) BOOT_SECTION_SIZE_KB=$(BOOT_SECTION_SIZE_KB)
+	printf "Bootloader$(QMK_BOOTLOADER_TYPE).hex copied to $(TARGET)_bootloader.hex\n"
+	cp lib/lufa/Bootloaders/$(QMK_BOOTLOADER_TYPE)/Bootloader$(QMK_BOOTLOADER_TYPE).hex $(TARGET)_bootloader.hex
+endif
+
+production: $(BUILD_DIR)/$(TARGET).hex bootloader cpfirmware
+	@cat $(BUILD_DIR)/$(TARGET).hex | awk '/^:00000001FF/ == 0' > $(TARGET)_production.hex
+	@cat $(TARGET)_bootloader.hex >> $(TARGET)_production.hex
+	echo "File sizes:"
+	$(SIZE) $(TARGET).hex $(TARGET)_bootloader.hex $(TARGET)_production.hex