Adding /wirish/boards/ for easier porting; shrank PIN_MAPs.

/wirish/boards/ contains xxx.h and xxx.cpp (for xxx=maple,
maple_native, maple_mini, maple_RET6).  The headers contain the
board-specific #defines that used to live in boards.h (except
BOARD_INIT, which was removed).  The CPP files contain the PIN_MAP
definitions that used to live in boards.cpp, and a proper boardInit()
function to replace the old BOARD_INIT macro.  This will make it
easier to add new boards in the future.

struct PinMapping was renamed struct stm32_pin_info, and was moved
into a new wirish_types.h.  Its external interrupt field was moved
into struct gpio_dev, which saves memory by storing an afio_exti_port
per port, rather than one per pin.  Also rearranged the stm32_pin_info
fields to improve packing.  Maple's PIN_MAP is now down to below 500
bytes.

2 files changed, 56 insertions, 38 deletions

diff --git a/libmaple/gpio.c b/libmaple/gpio.c
index 18b856b..5484e21 100644
--- a/libmaple/gpio.c
+++ b/libmaple/gpio.c
@@ -34,45 +34,52 @@
  */
 
 gpio_dev gpioa = {
-    .regs   = GPIOA_BASE,
-    .clk_id = RCC_GPIOA
+    .regs      = GPIOA_BASE,
+    .clk_id    = RCC_GPIOA,
+    .exti_port = AFIO_EXTI_PA,
 };
 gpio_dev* const GPIOA = &gpioa;
 
 gpio_dev gpiob = {
-    .regs   = GPIOB_BASE,
-    .clk_id = RCC_GPIOB
+    .regs      = GPIOB_BASE,
+    .clk_id    = RCC_GPIOB,
+    .exti_port = AFIO_EXTI_PB,
 };
 gpio_dev* const GPIOB = &gpiob;
 
 gpio_dev gpioc = {
-    .regs   = GPIOC_BASE,
-    .clk_id = RCC_GPIOC
+    .regs      = GPIOC_BASE,
+    .clk_id    = RCC_GPIOC,
+    .exti_port = AFIO_EXTI_PC,
 };
 gpio_dev* const GPIOC = &gpioc;
 
 gpio_dev gpiod = {
-    .regs   = GPIOD_BASE,
-    .clk_id = RCC_GPIOD
+    .regs      = GPIOD_BASE,
+    .clk_id    = RCC_GPIOD,
+    .exti_port = AFIO_EXTI_PD,
 };
 gpio_dev* const GPIOD = &gpiod;
 
 #ifdef STM32_HIGH_DENSITY
 gpio_dev gpioe = {
-    .regs   = GPIOE_BASE,
-    .clk_id = RCC_GPIOE
+    .regs      = GPIOE_BASE,
+    .clk_id    = RCC_GPIOE,
+    .exti_port = AFIO_EXTI_PE,
 };
 gpio_dev* const GPIOE = &gpioe;
 
 gpio_dev gpiof = {
-    .regs   = GPIOF_BASE,
-    .clk_id = RCC_GPIOF
+    .regs      = GPIOF_BASE,
+    .clk_id    = RCC_GPIOF,
+    .exti_port = AFIO_EXTI_PF,
 };
 gpio_dev* const GPIOF = &gpiof;
 
 gpio_dev gpiog = {
-    .regs   = GPIOG_BASE,
-    .clk_id = RCC_GPIOG
+    .regs      = GPIOG_BASE,
+    .clk_id    = RCC_GPIOG,
+    .exti_port = AFIO_EXTI_PG,
 };
 gpio_dev* const GPIOG = &gpiog;
 #endif
diff --git a/libmaple/gpio.h b/libmaple/gpio.h
index a8a4985..63ba0d5 100644
--- a/libmaple/gpio.h
+++ b/libmaple/gpio.h
@@ -47,19 +47,37 @@ extern "C"{
 
 /** GPIO register map type */
 typedef struct gpio_reg_map {
-    __io uint32 CRL;      ///< Port configuration register low
-    __io uint32 CRH;      ///< Port configuration register high
-    __io uint32 IDR;      ///< Port input data register
-    __io uint32 ODR;      ///< Port output data register
-    __io uint32 BSRR;     ///< Port bit set/reset register
-    __io uint32 BRR;      ///< Port bit reset register
-    __io uint32 LCKR;     ///< Port configuration lock register
+    __io uint32 CRL;      /**< Port configuration register low */
+    __io uint32 CRH;      /**< Port configuration register high */
+    __io uint32 IDR;      /**< Port input data register */
+    __io uint32 ODR;      /**< Port output data register */
+    __io uint32 BSRR;     /**< Port bit set/reset register */
+    __io uint32 BRR;      /**< Port bit reset register */
+    __io uint32 LCKR;     /**< Port configuration lock register */
 } gpio_reg_map;
 
+
+/**
+ * External interrupt line port selector.  Used to determine which
+ * GPIO port to map an external interrupt line onto. */
+/* (See AFIO sections, below) */
+typedef enum {
+    AFIO_EXTI_PA,               /**< Use PAx pin. */
+    AFIO_EXTI_PB,               /**< Use PBx pin. */
+    AFIO_EXTI_PC,               /**< Use PCx pin. */
+    AFIO_EXTI_PD,               /**< Use PDx pin. */
+#ifdef STM32_HIGH_DENSITY
+    AFIO_EXTI_PE,               /**< Use PEx pin. */
+    AFIO_EXTI_PF,               /**< Use PFx pin. */
+    AFIO_EXTI_PG,               /**< Use PGx pin. */
+#endif
+} afio_exti_port;
+
 /** GPIO device type */
 typedef struct gpio_dev {
-    gpio_reg_map *regs; ///< Register map
-    rcc_clk_id clk_id;  ///< RCC clock information
+    gpio_reg_map *regs;       /**< Register map */
+    rcc_clk_id clk_id;        /**< RCC clock information */
+    afio_exti_port exti_port; /**< AFIO external interrupt port value */
 } gpio_dev;
 
 extern gpio_dev gpioa;
@@ -145,6 +163,14 @@ void gpio_init_all(void);
 void gpio_set_mode(gpio_dev *dev, uint8 pin, gpio_pin_mode mode);
 
 /**
+ * @brief Get a GPIO port's corresponding afio_exti_port.
+ * @param dev GPIO device whose afio_exti_port to return.
+ */
+static inline afio_exti_port gpio_exti_port(gpio_dev *dev) {
+    return dev->exti_port;
+}
+
+/**
  * Set or reset a GPIO pin.
  *
  * Pin must have previously been configured to output mode.
@@ -260,21 +286,6 @@ typedef struct afio_reg_map {
 /* External interrupt configuration registers */
 
 /**
- * External interrupt line port selector.  Used to determine which
- * GPIO port to map an external interrupt line onto. */
-typedef enum {
-    AFIO_EXTI_PA,               /**< Use PAx pin. */
-    AFIO_EXTI_PB,               /**< Use PBx pin. */
-    AFIO_EXTI_PC,               /**< Use PCx pin. */
-    AFIO_EXTI_PD,               /**< Use PDx pin. */
-#ifdef STM32_HIGH_DENSITY
-    AFIO_EXTI_PE,               /**< Use PEx pin. */
-    AFIO_EXTI_PF,               /**< Use PFx pin. */
-    AFIO_EXTI_PG,               /**< Use PGx pin. */
-#endif
-} afio_exti_port;
-
-/**
  * External interrupt line numbers.
  */
 typedef enum {