Based on user/ft/stm32-dev-bridge, without the project-specific build

directories (and duplicated code).

1 files changed, 324 insertions, 0 deletions

diff --git a/src/stm-fmc.c b/src/stm-fmc.c
new file mode 100644
index 0000000..bc214d8
--- /dev/null
+++ b/src/stm-fmc.c
@@ -0,0 +1,324 @@
+//------------------------------------------------------------------------------
+// stm-fmc.c
+//------------------------------------------------------------------------------
+
+
+//------------------------------------------------------------------------------
+// Headers
+//------------------------------------------------------------------------------
+#include "stm-fmc.h"
+
+
+//------------------------------------------------------------------------------
+// Defined Values
+//------------------------------------------------------------------------------
+#define FMC_FPGA_BASE_ADDR              0x60000000
+#define FMC_FPGA_ADDR_MASK              0x00FFFFFC
+#define FMC_FPGA_NWAIT_MAX_POLL_TICKS   10
+
+#define FMC_GPIO_PORT_NWAIT             GPIOD
+#define FMC_GPIO_PIN_NWAIT              GPIO_PIN_6
+
+#define FMC_NWAIT_IDLE                  GPIO_PIN_SET
+
+
+//------------------------------------------------------------------------------
+// Variables
+//------------------------------------------------------------------------------
+static SRAM_HandleTypeDef _fmc_fpga_inst;
+
+
+//------------------------------------------------------------------------------
+// Prototypes
+//------------------------------------------------------------------------------
+static void _fmc_init_gpio(void);
+static void _fmc_init_params(void);
+static int _fmc_nwait_idle(void);
+
+
+//------------------------------------------------------------------------------
+void fmc_init(void)
+//------------------------------------------------------------------------------
+{
+  // configure fmc pins
+  _fmc_init_gpio();
+
+  // configure fmc registers
+  _fmc_init_params();
+}
+
+
+//------------------------------------------------------------------------------
+int fmc_write_32(uint32_t addr, uint32_t *data)
+//------------------------------------------------------------------------------
+{
+  // calculate target fpga address
+  uint32_t ptr = FMC_FPGA_BASE_ADDR + (addr & FMC_FPGA_ADDR_MASK);
+
+  // write data to fpga
+  HAL_StatusTypeDef ok = HAL_SRAM_Write_32b(&_fmc_fpga_inst, (uint32_t *)ptr, data, 1);
+
+  // check for error
+  if (ok != HAL_OK) return -1;
+
+  // wait for transaction to complete
+  int wait = _fmc_nwait_idle();
+
+  // check for timeout
+  if (wait != 0) return -1;
+
+  // everything went ok
+  return 0;
+}
+
+
+//------------------------------------------------------------------------------
+int fmc_read_32(uint32_t addr, uint32_t *data)
+//------------------------------------------------------------------------------
+{
+  // calculate target fpga address
+  uint32_t ptr = FMC_FPGA_BASE_ADDR + (addr & FMC_FPGA_ADDR_MASK);
+
+  // perform dummy read transaction
+  HAL_StatusTypeDef ok = HAL_SRAM_Read_32b(&_fmc_fpga_inst, (uint32_t *)ptr, data, 1);
+
+  // check for error
+  if (ok != HAL_OK) return -1;
+
+  // wait for dummy transaction to complete
+  int wait = _fmc_nwait_idle();
+
+  // check for timeout
+  if (wait != 0) return -1;
+
+  // read data from fpga
+  ok = HAL_SRAM_Read_32b(&_fmc_fpga_inst, (uint32_t *)ptr, data, 1);
+
+  // check for error
+  if (ok != HAL_OK) return -1;
+
+  // wait for read transaction to complete
+  wait = _fmc_nwait_idle();
+
+  // check for timeout
+  if (wait != 0) return -1;
+
+  // everything went ok
+  return 0;
+}
+
+
+//------------------------------------------------------------------------------
+static int _fmc_nwait_idle()
+//------------------------------------------------------------------------------
+{
+  int cnt; // counter
+
+  // poll NWAIT (number of iterations is limited)
+  for (cnt=0; cnt<FMC_FPGA_NWAIT_MAX_POLL_TICKS; cnt++)
+    {
+      // read pin state
+      GPIO_PinState nwait = HAL_GPIO_ReadPin(FMC_GPIO_PORT_NWAIT, FMC_GPIO_PIN_NWAIT);
+
+      // stop waiting if fpga is ready
+      if (nwait == FMC_NWAIT_IDLE) break;
+    }
+
+  // check for timeout
+  if (cnt >= FMC_FPGA_NWAIT_MAX_POLL_TICKS) return -1;
+
+  // ok
+  return 0;
+}
+
+//------------------------------------------------------------------------------
+static void _fmc_init_gpio(void)
+//------------------------------------------------------------------------------
+{
+  // enable gpio clocks
+  __GPIOA_CLK_ENABLE();
+  __GPIOB_CLK_ENABLE();
+  __GPIOD_CLK_ENABLE();
+  __GPIOE_CLK_ENABLE();
+  __GPIOF_CLK_ENABLE();
+  __GPIOG_CLK_ENABLE();
+  __GPIOH_CLK_ENABLE();
+  __GPIOI_CLK_ENABLE();
+
+  // enable fmc clock
+  __FMC_CLK_ENABLE();
+
+  // structure
+  GPIO_InitTypeDef GPIO_InitStruct;
+
+  // Port B
+  GPIO_InitStruct.Pin = GPIO_PIN_7;
+  GPIO_InitStruct.Mode = GPIO_MODE_AF_PP;
+  GPIO_InitStruct.Pull = GPIO_NOPULL;
+  GPIO_InitStruct.Speed = GPIO_SPEED_HIGH;
+  GPIO_InitStruct.Alternate = GPIO_AF12_FMC;
+  HAL_GPIO_Init(GPIOB, &GPIO_InitStruct);
+
+  // Port D
+  GPIO_InitStruct.Pin = GPIO_PIN_8|GPIO_PIN_9|GPIO_PIN_10|GPIO_PIN_11
+    |GPIO_PIN_12|GPIO_PIN_13|GPIO_PIN_14|GPIO_PIN_15
+    |GPIO_PIN_0|GPIO_PIN_1|GPIO_PIN_3|GPIO_PIN_4
+    |GPIO_PIN_5|GPIO_PIN_7;
+  GPIO_InitStruct.Mode = GPIO_MODE_AF_PP;
+  GPIO_InitStruct.Pull = GPIO_NOPULL;
+  GPIO_InitStruct.Speed = GPIO_SPEED_HIGH;
+  GPIO_InitStruct.Alternate = GPIO_AF12_FMC;
+  HAL_GPIO_Init(GPIOD, &GPIO_InitStruct);
+
+  /*
+   * When FMC is working with fixed latency, NWAIT pin must not be
+   * configured in AF mode, according to STM32F429 errata.
+   */
+
+  // Port D (GPIO!)
+  GPIO_InitStruct.Pin = GPIO_PIN_6;
+  GPIO_InitStruct.Mode = GPIO_MODE_INPUT;
+  GPIO_InitStruct.Pull = GPIO_PULLUP;
+  HAL_GPIO_Init(GPIOD, &GPIO_InitStruct);
+
+  // Port E
+  GPIO_InitStruct.Pin = GPIO_PIN_3|GPIO_PIN_4|GPIO_PIN_5|GPIO_PIN_7
+    |GPIO_PIN_8|GPIO_PIN_9|GPIO_PIN_10|GPIO_PIN_11
+    |GPIO_PIN_12|GPIO_PIN_13|GPIO_PIN_14|GPIO_PIN_15;
+  GPIO_InitStruct.Mode = GPIO_MODE_AF_PP;
+  GPIO_InitStruct.Pull = GPIO_NOPULL;
+  GPIO_InitStruct.Speed = GPIO_SPEED_HIGH;
+  GPIO_InitStruct.Alternate = GPIO_AF12_FMC;
+  HAL_GPIO_Init(GPIOE, &GPIO_InitStruct);
+
+  // Port F
+  GPIO_InitStruct.Pin = GPIO_PIN_0|GPIO_PIN_1|GPIO_PIN_2|GPIO_PIN_3
+    |GPIO_PIN_4|GPIO_PIN_5|GPIO_PIN_12|GPIO_PIN_13
+    |GPIO_PIN_14|GPIO_PIN_15;
+  GPIO_InitStruct.Mode = GPIO_MODE_AF_PP;
+  GPIO_InitStruct.Pull = GPIO_NOPULL;
+  GPIO_InitStruct.Speed = GPIO_SPEED_HIGH;
+  GPIO_InitStruct.Alternate = GPIO_AF12_FMC;
+  HAL_GPIO_Init(GPIOF, &GPIO_InitStruct);
+
+  // Port G
+  GPIO_InitStruct.Pin = GPIO_PIN_0|GPIO_PIN_1|GPIO_PIN_2|GPIO_PIN_3
+    |GPIO_PIN_4|GPIO_PIN_5;
+  GPIO_InitStruct.Mode = GPIO_MODE_AF_PP;
+  GPIO_InitStruct.Pull = GPIO_NOPULL;
+  GPIO_InitStruct.Speed = GPIO_SPEED_HIGH;
+  GPIO_InitStruct.Alternate = GPIO_AF12_FMC;
+  HAL_GPIO_Init(GPIOG, &GPIO_InitStruct);
+
+  // Port H
+  GPIO_InitStruct.Pin = GPIO_PIN_8|GPIO_PIN_9|GPIO_PIN_10|GPIO_PIN_11
+    |GPIO_PIN_12|GPIO_PIN_13|GPIO_PIN_14|GPIO_PIN_15;
+  GPIO_InitStruct.Mode = GPIO_MODE_AF_PP;
+  GPIO_InitStruct.Pull = GPIO_NOPULL;
+  GPIO_InitStruct.Speed = GPIO_SPEED_HIGH;
+  GPIO_InitStruct.Alternate = GPIO_AF12_FMC;
+  HAL_GPIO_Init(GPIOH, &GPIO_InitStruct);
+
+  // Port I
+  GPIO_InitStruct.Pin = GPIO_PIN_9|GPIO_PIN_10|GPIO_PIN_0|GPIO_PIN_1
+    |GPIO_PIN_2|GPIO_PIN_3|GPIO_PIN_6|GPIO_PIN_7;
+  GPIO_InitStruct.Mode = GPIO_MODE_AF_PP;
+  GPIO_InitStruct.Pull = GPIO_NOPULL;
+  GPIO_InitStruct.Speed = GPIO_SPEED_HIGH;
+  GPIO_InitStruct.Alternate = GPIO_AF12_FMC;
+  HAL_GPIO_Init(GPIOI, &GPIO_InitStruct);
+}
+
+
+//------------------------------------------------------------------------------
+static void _fmc_init_params(void)
+//------------------------------------------------------------------------------
+{
+  /*
+   * fill internal fields
+   */
+  _fmc_fpga_inst.Instance = FMC_NORSRAM_DEVICE;
+  _fmc_fpga_inst.Extended = FMC_NORSRAM_EXTENDED_DEVICE;
+
+
+  /*
+   * configure fmc interface settings
+   */
+
+  // use the first bank and corresponding chip select
+  _fmc_fpga_inst.Init.NSBank = FMC_NORSRAM_BANK1;
+
+  // data and address buses are separate
+  _fmc_fpga_inst.Init.DataAddressMux = FMC_DATA_ADDRESS_MUX_DISABLE;
+
+  // fpga mimics psram-type memory
+  _fmc_fpga_inst.Init.MemoryType = FMC_MEMORY_TYPE_PSRAM;
+
+  // data bus is 32-bit
+  _fmc_fpga_inst.Init.MemoryDataWidth = FMC_NORSRAM_MEM_BUS_WIDTH_32;
+
+  // read transaction is sync
+  _fmc_fpga_inst.Init.BurstAccessMode = FMC_BURST_ACCESS_MODE_ENABLE;
+
+  // this _must_ be configured to high, according to errata, otherwise
+  // the processor may hang after trying to access fpga via fmc
+  _fmc_fpga_inst.Init.WaitSignalPolarity = FMC_WAIT_SIGNAL_POLARITY_HIGH;
+
+  // wrap mode is not supported
+  _fmc_fpga_inst.Init.WrapMode = FMC_WRAP_MODE_DISABLE;
+
+  // don't care in fixed latency mode
+  _fmc_fpga_inst.Init.WaitSignalActive = FMC_WAIT_TIMING_DURING_WS;
+
+  // allow write access to fpga
+  _fmc_fpga_inst.Init.WriteOperation = FMC_WRITE_OPERATION_ENABLE;
+
+  // use fixed latency mode (ignore wait signal)
+  _fmc_fpga_inst.Init.WaitSignal = FMC_WAIT_SIGNAL_DISABLE;
+
+  // write and read have same timing
+  _fmc_fpga_inst.Init.ExtendedMode = FMC_EXTENDED_MODE_DISABLE;
+
+  // don't care in sync mode
+  _fmc_fpga_inst.Init.AsynchronousWait = FMC_ASYNCHRONOUS_WAIT_DISABLE;
+
+  // write transaction is sync
+  _fmc_fpga_inst.Init.WriteBurst = FMC_WRITE_BURST_ENABLE;
+
+  // keep clock always active
+  _fmc_fpga_inst.Init.ContinuousClock = FMC_CONTINUOUS_CLOCK_SYNC_ASYNC;
+
+  /*
+   * configure fmc timing parameters
+   */
+  FMC_NORSRAM_TimingTypeDef fmc_timing;
+
+  // don't care in sync mode
+  fmc_timing.AddressSetupTime = 15;
+
+  // don't care in sync mode
+  fmc_timing.AddressHoldTime = 15;
+
+  // don't care in sync mode
+  fmc_timing.DataSetupTime = 255;
+
+  // not needed, since nwait will be polled manually
+  fmc_timing.BusTurnAroundDuration = 0;
+
+  // use smallest allowed divisor for best performance
+  fmc_timing.CLKDivision = 2;
+
+  // stm is too slow to work with min allowed 2-cycle latency
+  fmc_timing.DataLatency = 3;
+
+  // don't care in sync mode
+  fmc_timing.AccessMode = FMC_ACCESS_MODE_A;
+
+  // initialize fmc
+  HAL_SRAM_Init(&_fmc_fpga_inst, &fmc_timing, NULL);
+}
+
+
+//------------------------------------------------------------------------------
+// EOF
+//------------------------------------------------------------------------------