/*
* stm-fmc.c
* ---------
* Functions to set up and use the FMC bus.
*
* Copyright (c) 2015, NORDUnet A/S All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are
* met:
* - Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
*
* - Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* - Neither the name of the NORDUnet nor the names of its contributors may
* be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
* IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
* TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
* PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
* HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
* TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
* PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
* LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
* NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
//------------------------------------------------------------------------------
// Headers
//------------------------------------------------------------------------------
#include "stm-fmc.h"
#include "stm32f4xx_hal.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
//------------------------------------------------------------------------------
