nrf nits

Author: cpq

templates/blinky/nRF52840dk/Makefile

@@ -1,19 +1,27 @@
 CFLAGS ?= -W -Wall -Wextra -Werror -Wundef -Wshadow -Wdouble-promotion -Wformat-truncation -fno-common
-CFLAGS += -g3 -O0 -ffunction-sections -fdata-sections -Wno-shadow
+CFLAGS += -g3 -Os -ffunction-sections -fdata-sections -Wno-shadow
 CFLAGS += -mcpu=cortex-m4 -mthumb -mfloat-abi=hard -mfpu=fpv4-sp-d16
 LDFLAGS ?= -Tlink.ld -nostartfiles -nostdlib --specs nano.specs -lc -lgcc -Wl,--gc-sections
-SOURCES = main.c
 
+SOURCES = main.c
 
-firmware.elf: hal.h link.ld Makefile $(SOURCES) 
+firmware.elf: hal.h link.ld Makefile $(SOURCES) #cmsis_core cmsis_nrf
 	arm-none-eabi-gcc $(SOURCES) $(CFLAGS) $(CFLAGS_EXTRA) $(LDFLAGS) -o $@
+	arm-none-eabi-size $@
 
-firwmare.hex:
-	arm-none-eabi-objcopy -Oihex firmware.elf firmware.hex
+firmware.bin firmware.hex: firmware.elf
+	arm-none-eabi-objcopy -O ihex firmware.elf firmware.hex
+	arm-none-eabi-objcopy -O binary firmware.elf firmware.bin
 
 flash: 
 	nrfjprog -f NRF52 --program firmware.hex --recover --verify
 	nrfjprog -f NRF52 --reset
 
+cmsis_core:
+	git clone -c advice.detachedHead=false -q --depth 1 -b 5.9.0 https://github.com/ARM-software/CMSIS_5 $@
+
+cmsis_nrf:
+	curl -sL https://developer.nordicsemi.com/nRF5_SDK/pieces/nRF_DeviceFamilyPack/NordicSemiconductor.nRF_DeviceFamilyPack.8.44.1.pack -o x.zip && mkdir -p $@ && (cd $@ && unzip -q ../x.zip && rm -f ../x.zip)
+
 clean:
 	rm -rf firmware.*

templates/blinky/nRF52840dk/hal.h

@@ -1,38 +1,44 @@
-#define P0 ((struct gpio *) 0x50000000)
-#define P1 ((struct gpio *) 0x50000300)
+#pragma once
 
-enum { GPIO_MODE_INPUT, GPIO_MODE_OUTPUT };
-enum { LOW, HIGH };
+#include <stdbool.h>
+#include <stdint.h>
 
-struct gpio {
-  volatile uint32_t RESERVED[321], OUT, OUTSET, OUTCLR, IN, DIR, DIRSET, DIRCLR,
-      LATCH, DETECTMODE, RESERVED_SECOND[118], PIN_CNF[32];
-};
+#include "nrf52.h"
 
-void set_gpio_mode(struct gpio *port, int pin, int mode, int pull) {
-  if (pull == 0) {
-    port->PIN_CNF[pin] = mode << 0;
-  } else {
-    port->PIN_CNF[pin] = mode << 0 | pull << 2;
-  }
+#define BIT(x) (1UL << (x))
+#define CLRSET(R, CLEARMASK, SETMASK) (R) = ((R) & ~(CLEARMASK)) | (SETMASK)
+#define PIN(bank, num) ((((bank) - 'A') << 8) | (num))
+#define PINNO(pin) (pin & 255)
+#define PINBANK(pin) (pin >> 8)
+
+static inline void spin(volatile uint32_t count) {
+  while (count--) (void) 0;
 }
 
-int gpio_read(struct gpio *port, int pin) {
-  uint32_t button = ~(port->IN);
-  if (button & (1 << pin)) {
-    return 1;
-  } else {
-    return 0;
-  }
+#define GPIO(N) ((NRF_GPIO_Type *) ((NRF_P0_BASE) + 0x300 * (N)))
+
+static inline NRF_GPIO_Type *gpio_bank(uint16_t pin) {
+  return GPIO(PINBANK(pin));
 }
-void gpio_write(struct gpio *port, int pin, int value) {
-  if (value == 0) {
-    port->OUTSET = 1 << pin;
-  } else {
-    port->OUTCLR = 1 << pin;
-  }
+
+enum { GPIO_MODE_INPUT = 0, GPIO_MODE_OUTPUT = 1 };
+enum { GPIO_PULL_NONE = 0, GPIO_PULL_DOWN = 1, GPIO_PULL_UP = 3U };
+
+void gpio_init(uint16_t pin, uint8_t mode, uint8_t pull) {
+  NRF_GPIO_Type *gpio = gpio_bank(pin);
+  gpio->PIN_CNF[pin] = (mode & 1U) << 0 | (pull & 3U) << 2U;
 }
 
-static inline void spin(volatile uint32_t count) {
-  while (count--) (void) 0;
+static inline bool gpio_read(uint16_t pin) {
+  NRF_GPIO_Type *gpio = gpio_bank(pin);
+  return ~(gpio->IN) & BIT(PINNO(pin));
+}
+
+static inline void gpio_write(uint16_t pin, bool value) {
+  NRF_GPIO_Type *gpio = gpio_bank(pin);
+  if (value) {
+    gpio->OUTSET = BIT(PINNO(pin));
+  } else {
+    gpio->OUTCLR = BIT(PINNO(pin));
+  }
 }

templates/blinky/nRF52840dk/link.ld

@@ -1,7 +1,7 @@
 ENTRY(Reset_Handler);
 MEMORY {
-  flash(rx) : ORIGIN = 0x00000000, LENGTH = 1M
-  sram(rwx) : ORIGIN = 0x20000000, LENGTH = 256k
+  flash(rx) : ORIGIN = 0x00000000, LENGTH = 512k
+  sram(rwx) : ORIGIN = 0x20000000, LENGTH = 64k
 }
 _estack     = ORIGIN(sram) + LENGTH(sram);
 

templates/blinky/nRF52840dk/main.c

@@ -1,25 +1,24 @@
-#include <stdint.h>
 #include "hal.h"
 
-#define LED1 19
+#define LED1 PIN('A', 17)
 
 int main(void) {
-  set_gpio_mode(P0, LED1, GPIO_MODE_OUTPUT, 0);
+  gpio_init(LED1, GPIO_MODE_OUTPUT, 0);
 
-  int level = 0;
-  while (1) {
-    gpio_write(P0, LED1, level);
+  for (;;) {
+    gpio_write(LED1, true);
+    spin(9999999);
+    gpio_write(LED1, false);
     spin(9999999);
-    level = !level;
   }
 }
 
 // Startup code
 __attribute__((naked, noreturn)) void Reset_Handler(void) {
   // memset .bss to zero, and copy .data section to RAM region
-  extern long _sbss, _ebss, _sdata, _edata, _sidata;
-  for (long *dst = &_sbss; dst < &_ebss; dst++) *dst = 0;
-  for (long *dst = &_sdata, *src = &_sidata; dst < &_edata;) *dst++ = *src++;
+  extern uint32_t _sbss, _ebss, _sdata, _edata, _sidata;
+  for (uint32_t *dst = &_sbss; dst < &_ebss; dst++) *dst = 0;
+  for (uint32_t *dst = &_sdata, *src = &_sidata; dst < &_edata;) *dst++ = *src++;
 
   main();             // Call main()
   for (;;) (void) 0;  // Infinite loop in the case if main() returns