Add interface2

interface2/firmware/src/ice40.cpp

@@ -0,0 +1,113 @@
+// Copyright (c) 2020, Andrew Kay
+//
+// Permission to use, copy, modify, and/or distribute this software for any
+// purpose with or without fee is hereby granted, provided that the above
+// copyright notice and this permission notice appear in all copies.
+//
+// THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+// WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+// MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+// ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+// WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+// ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+// OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+
+#include "pins.h"
+
+#include "ice40.h"
+
+ICE40::ICE40()
+{
+    _isConfigured = false;
+}
+
+inline void clock()
+{
+    LL_GPIO_ResetOutputPin(ICE40_SCK_GPIO_Port, ICE40_SCK_Pin);
+
+    for (int index = 0; index < 4; index++) {
+        asm volatile("nop\n\t");
+    }
+
+    LL_GPIO_SetOutputPin(ICE40_SCK_GPIO_Port, ICE40_SCK_Pin);
+}
+
+bool ICE40::configure(const uint8_t *bitstream, size_t bitstreamCount)
+{
+    _isConfigured = false;
+
+    // Configure GPIO.
+    __HAL_RCC_GPIOA_CLK_ENABLE();
+    __HAL_RCC_GPIOB_CLK_ENABLE();
+
+    HAL_GPIO_WritePin(GPIOA, ICE40_CS_Pin | ICE40_SCK_Pin | ICE40_SDI_Pin, GPIO_PIN_RESET);
+    HAL_GPIO_WritePin(GPIOB, ICE40_CRESET_Pin, GPIO_PIN_RESET);
+
+    GPIO_InitTypeDef gpioInit = { 0 };
+
+    gpioInit.Pin = ICE40_CS_Pin | ICE40_SCK_Pin | ICE40_SDI_Pin;
+    gpioInit.Mode = GPIO_MODE_OUTPUT_PP;
+    gpioInit.Pull = GPIO_NOPULL;
+    gpioInit.Speed = GPIO_SPEED_FREQ_LOW;
+
+    HAL_GPIO_Init(GPIOA, &gpioInit);
+
+    gpioInit.Pin = ICE40_CRESET_Pin;
+    gpioInit.Mode = GPIO_MODE_OUTPUT_PP;
+    gpioInit.Pull = GPIO_NOPULL;
+    gpioInit.Speed = GPIO_SPEED_FREQ_LOW;
+
+    HAL_GPIO_Init(GPIOB, &gpioInit);
+
+    gpioInit.Pin = ICE40_CDONE_Pin;
+    gpioInit.Mode = GPIO_MODE_INPUT;
+    gpioInit.Pull = GPIO_NOPULL;
+
+    HAL_GPIO_Init(GPIOB, &gpioInit);
+
+    // Set initial GPIO state.
+    HAL_GPIO_WritePin(ICE40_CS_GPIO_Port, ICE40_CS_Pin | ICE40_SCK_Pin, GPIO_PIN_SET);
+    HAL_GPIO_WritePin(ICE40_CRESET_GPIO_Port, ICE40_CRESET_Pin, GPIO_PIN_SET);
+
+    // Assert CS and reset.
+    HAL_GPIO_WritePin(ICE40_CS_GPIO_Port, ICE40_CS_Pin, GPIO_PIN_RESET);
+
+    HAL_GPIO_WritePin(ICE40_CRESET_GPIO_Port, ICE40_CRESET_Pin, GPIO_PIN_RESET);
+
+    HAL_Delay(1);
+
+    HAL_GPIO_WritePin(ICE40_CRESET_GPIO_Port, ICE40_CRESET_Pin, GPIO_PIN_SET);
+
+    HAL_Delay(1);
+
+    // Send the bitstream.
+    for (size_t index = 0; index < bitstreamCount; index++) {
+        uint8_t byte = bitstream[index];
+
+        for (int bitIndex = 7; bitIndex >= 0; bitIndex--) {
+            if ((byte >> bitIndex) & 0x01) {
+                LL_GPIO_SetOutputPin(ICE40_SDI_GPIO_Port, ICE40_SDI_Pin);
+            } else {
+                LL_GPIO_ResetOutputPin(ICE40_SDI_GPIO_Port, ICE40_SDI_Pin);
+            }
+
+            clock();
+        }
+    }
+
+    // Check done.
+    bool done = LL_GPIO_IsInputPinSet(ICE40_CDONE_GPIO_Port, ICE40_CDONE_Pin);
+
+    if (done) {
+        for (int index = 0; index < 49; index++) {
+            clock();
+        }
+    }
+
+    // Deassert CS.
+    HAL_GPIO_WritePin(ICE40_CS_GPIO_Port, ICE40_CS_Pin, GPIO_PIN_SET);
+
+    _isConfigured = done;
+
+    return _isConfigured;
+}