263 lines
12 KiB
C
Executable File

#pragma once
#include "blackfin.h"
#include <unistd.h> // usleep
/**
* Intel: Embedded Peripherals IP User Guide
* https://www.intel.com/content/dam/www/programmable/us/en/pdfs/literature/ug/ug_embedded_ip.pdf
* To be defined
*
* (in blackfin.h)
* I2C_CLOCK_MHZ
*
* (RegisterDefs.h)
* I2C_SCL_LOW_COUNT_REG
* I2C_SCL_HIGH_COUNT_REG
* I2C_SDA_HOLD_REG
* I2C_CONTROL_REG
* I2C_STATUS_REG
* I2C_TRANSFER_COMMAND_FIFO_REG
* I2C_RX_DATA_FIFO_LEVEL_REG
* I2C_RX_DATA_FIFO_REG
*/
#define I2C_DATA_RATE_KBPS (200)
/** Control Register */
#define I2C_CTRL_ENBLE_CORE_OFST (0)
#define I2C_CTRL_ENBLE_CORE_MSK (0x00000001 << I2C_CTRL_ENBLE_CORE_OFST)
#define I2C_CTRL_BUS_SPEED_OFST (1)
#define I2C_CTRL_BUS_SPEED_MSK (0x00000001 << I2C_CTRL_BUS_SPEED_OFST)
#define I2C_CTRL_BUS_SPEED_STNDRD_100_VAL ((0x0 << I2C_CTRL_BUS_SPEED_OFST) & I2C_CTRL_BUS_SPEED_MSK) // standard mode (up to 100 kbps)
#define I2C_CTRL_BUS_SPEED_FAST_400_VAL ((0x1 << I2C_CTRL_BUS_SPEED_OFST) & I2C_CTRL_BUS_SPEED_MSK) // fast mode (up to 400 kbps)
/** if actual level of transfer command fifo <= thd level, TX_READY interrupt asserted */
#define I2C_CTRL_TFR_CMD_FIFO_THD_OFST (2)
#define I2C_CTRL_TFR_CMD_FIFO_THD_MSK (0x00000003 << I2C_CTRL_TFR_CMD_FIFO_THD_OFST)
#define I2C_CTRL_TFR_CMD_EMPTY_VAL ((0x0 << I2C_CTRL_TFR_CMD_FIFO_THD_OFST) & I2C_CTRL_TFR_CMD_FIFO_THD_MSK)
#define I2C_CTRL_TFR_CMD_ONE_FOURTH_VAL ((0x1 << I2C_CTRL_TFR_CMD_FIFO_THD_OFST) & I2C_CTRL_TFR_CMD_FIFO_THD_MSK)
#define I2C_CTRL_TFR_CMD_ONE_HALF_VAL ((0x2 << I2C_CTRL_TFR_CMD_FIFO_THD_OFST) & I2C_CTRL_TFR_CMD_FIFO_THD_MSK)
#define I2C_CTRL_TFR_CMD_NOT_FULL_VAL ((0x3 << I2C_CTRL_TFR_CMD_FIFO_THD_OFST) & I2C_CTRL_TFR_CMD_FIFO_THD_MSK)
/** if actual level of receive data fifo <= thd level, RX_READY interrupt asserted */
#define I2C_CTRL_RX_DATA_FIFO_THD_OFST (4)
#define I2C_CTRL_RX_DATA_FIFO_THD_MSK (0x00000003 << I2C_CTRL_RX_DATA_FIFO_THD_OFST)
#define I2C_CTRL_RX_DATA_1_VALID_ENTRY_VAL ((0x0 << I2C_CTRL_RX_DATA_FIFO_THD_OFST) & I2C_CTRL_RX_DATA_FIFO_THD_MSK)
#define I2C_CTRL_RX_DATA_ONE_FOURTH_VAL ((0x1 << I2C_CTRL_RX_DATA_FIFO_THD_OFST) & I2C_CTRL_RX_DATA_FIFO_THD_MSK)
#define I2C_CTRL_RX_DATA_ONE_HALF_VAL ((0x2 << I2C_CTRL_RX_DATA_FIFO_THD_OFST) & I2C_CTRL_RX_DATA_FIFO_THD_MSK)
#define I2C_CTRL_RX_DATA_FULL_VAL ((0x3 << I2C_CTRL_RX_DATA_FIFO_THD_OFST) & I2C_CTRL_RX_DATA_FIFO_THD_MSK)
/** Transfer Command Fifo register */
#define I2C_TFR_CMD_RW_OFST (0)
#define I2C_TFR_CMD_RW_MSK (0x00000001 << I2C_TFR_CMD_RW_OFST)
#define I2C_TFR_CMD_RW_WRITE_VAL ((0x0 << I2C_TFR_CMD_RW_OFST) & I2C_TFR_CMD_RW_MSK)
#define I2C_TFR_CMD_RW_READ_VAL ((0x1 << I2C_TFR_CMD_RW_OFST) & I2C_TFR_CMD_RW_MSK)
#define I2C_TFR_CMD_ADDR_OFST (1)
#define I2C_TFR_CMD_ADDR_MSK (0x0000007F << I2C_TFR_CMD_ADDR_OFST)
/** when writing, rw and addr converts to data to be written mask */
#define I2C_TFR_CMD_DATA_FR_WR_OFST (0)
#define I2C_TFR_CMD_DATA_FR_WR_MSK (0x000000FF << I2C_TFR_CMD_DATA_FR_WR_OFST)
#define I2C_TFR_CMD_STOP_OFST (8)
#define I2C_TFR_CMD_STOP_MSK (0x00000001 << I2C_TFR_CMD_STOP_OFST)
#define I2C_TFR_CMD_RPTD_STRT_OFST (9)
#define I2C_TFR_CMD_RPTD_STRT_MSK (0x00000001 << I2C_TFR_CMD_RPTD_STRT_OFST)
/** Receive DataFifo register */
#define I2C_RX_DATA_FIFO_RXDATA_OFST (0)
#define I2C_RX_DATA_FIFO_RXDATA_MSK (0x000000FF << I2C_RX_DATA_FIFO_RXDATA_OFST)
/** Status register */
#define I2C_STATUS_BUSY_OFST (0)
#define I2C_STATUS_BUSY_MSK (0x00000001 << I2C_STATUS_BUSY_OFST)
/** SCL Low Count register */
#define I2C_SCL_LOW_COUNT_PERIOD_OFST (0)
#define I2C_SCL_LOW_COUNT_PERIOD_MSK (0x0000FFFF << I2C_SCL_LOW_COUNT_PERIOD_OFST)
/** SCL High Count register */
#define I2C_SCL_HIGH_COUNT_PERIOD_OFST (0)
#define I2C_SCL_HIGH_COUNT_PERIOD_MSK (0x0000FFFF << I2C_SCL_HIGH_COUNT_PERIOD_OFST)
/** SDA Hold Count register */
#define I2C_SDA_HOLD_COUNT_PERIOD_OFST (0)
#define I2C_SDA_HOLD_COUNT_PERIOD_MSK (0x0000FFFF << I2C_SDA_HOLD_COUNT_PERIOD_OFST)
/** Receive Data Fifo Level register */
//#define I2C_RX_DATA_FIFO_LVL_OFST (0)
//#define I2C_RX_DATA_FIFO_LVL_MSK (0x000000FF << I2C_RX_DATA_FIFO_LVL_OFST)
uint32_t I2C_Control_Reg = 0x0;
uint32_t I2C_Status_Reg = 0x0;
uint32_t I2C_Rx_Data_Fifo_Reg = 0x0;
uint32_t I2C_Rx_Data_Fifo_Level_Reg = 0x0;
uint32_t I2C_Scl_Low_Count_Reg = 0x0;
uint32_t I2C_Scl_High_Count_Reg = 0x0;
uint32_t I2C_Sda_Hold_Reg = 0x0;
uint32_t I2C_Transfer_Command_Fifo_Reg = 0x0;
/**
* Configure the I2C core,
* Enable core and
* Calibrate the calibration register for current readout
* @param creg control register (defined in RegisterDefs.h)
* @param sreg status register (defined in RegisterDefs.h)
* @param rreg rx data fifo register (defined in RegisterDefs.h)
* @param rlvlreg rx data fifo level register (defined in RegisterDefs.h)
* @param slreg scl low count register (defined in RegisterDefs.h)
* @param shreg scl high count register (defined in RegisterDefs.h)
* @param sdreg sda hold register (defined in RegisterDefs.h)
* @param treg transfer command fifo register (defined in RegisterDefs.h)
*/
void I2C_ConfigureI2CCore(uint32_t creg, uint32_t sreg,
uint32_t rreg, uint32_t rlvlreg,
uint32_t slreg, uint32_t shreg, uint32_t sdreg, uint32_t treg) {
FILE_LOG(logINFO, ("\tConfiguring I2C Core for %d kbps:\n", I2C_DATA_RATE_KBPS));
FILE_LOG(logDEBUG1,("controlreg,:0x%x, statusreg,:0x%x, "
"rxrdatafiforeg: 0x%x, rxdatafifocountreg,:0x%x, "
"scllow,:0x%x, sclhighreg,:0x%x, sdaholdreg,:0x%x, transfercmdreg,:0x%x\n",
creg, sreg, rreg, rlvlreg, slreg, shreg, sdreg, treg));
I2C_Control_Reg = creg;
I2C_Status_Reg = sreg;
I2C_Rx_Data_Fifo_Reg = rreg;
I2C_Rx_Data_Fifo_Level_Reg = rlvlreg;
I2C_Scl_Low_Count_Reg = slreg;
I2C_Scl_High_Count_Reg = shreg;
I2C_Sda_Hold_Reg = sdreg;
I2C_Transfer_Command_Fifo_Reg = treg;
// calculate scl low and high period count
uint32_t sclPeriodNs = ((1000.00 * 1000.00 * 1000.00) / ((double)I2C_DATA_RATE_KBPS * 1000.00));
// scl low period same as high period
uint32_t sclLowPeriodNs = sclPeriodNs / 2;
// convert to us, then to clock (defined in blackfin.h)
uint32_t sclLowPeriodCount = (sclLowPeriodNs / 1000.00) * I2C_CLOCK_MHZ;
// calculate sda hold data count
uint32_t sdaDataHoldTimeNs = (sclLowPeriodNs / 2); // scl low period same as high period
// convert to us, then to clock (defined in blackfin.h)
uint32_t sdaDataHoldCount = ((sdaDataHoldTimeNs / 1000.00) * I2C_CLOCK_MHZ);
FILE_LOG(logINFO, ("\tSetting SCL Low Period: %d ns (%d clocks)\n", sclLowPeriodNs, sclLowPeriodCount));
bus_w(I2C_Scl_Low_Count_Reg, bus_r(I2C_Scl_Low_Count_Reg) |
((sclLowPeriodCount << I2C_SCL_LOW_COUNT_PERIOD_OFST) & I2C_SCL_LOW_COUNT_PERIOD_MSK));
FILE_LOG(logDEBUG1, ("SCL Low reg:0x%x\n", bus_r(I2C_Scl_Low_Count_Reg)));
FILE_LOG(logINFO, ("\tSetting SCL High Period: %d ns (%d clocks)\n", sclLowPeriodNs, sclLowPeriodCount));
bus_w(I2C_Scl_High_Count_Reg, bus_r(I2C_Scl_High_Count_Reg) |
((sclLowPeriodCount << I2C_SCL_HIGH_COUNT_PERIOD_OFST) & I2C_SCL_HIGH_COUNT_PERIOD_MSK));
FILE_LOG(logDEBUG1, ("SCL High reg:0x%x\n", bus_r(I2C_Scl_High_Count_Reg)));
FILE_LOG(logINFO, ("\tSetting SDA Hold Time: %d ns (%d clocks)\n", sdaDataHoldTimeNs, sdaDataHoldCount));
bus_w(I2C_Sda_Hold_Reg, bus_r(I2C_Sda_Hold_Reg) |
((sdaDataHoldCount << I2C_SDA_HOLD_COUNT_PERIOD_OFST) & I2C_SDA_HOLD_COUNT_PERIOD_MSK));
FILE_LOG(logDEBUG1, ("SDA Hold reg:0x%x\n", bus_r(I2C_Sda_Hold_Reg)));
FILE_LOG(logINFO, ("\tEnabling core and bus speed to fast (up to 400 kbps)\n"));
bus_w(I2C_Control_Reg, bus_r(I2C_Control_Reg) |
I2C_CTRL_ENBLE_CORE_MSK | I2C_CTRL_BUS_SPEED_FAST_400_VAL);// fixme: (works?)
FILE_LOG(logDEBUG1, ("Control reg:0x%x\n", bus_r(I2C_Control_Reg)));
//The INA226 supports the transmission protocol for fast mode (1 kHz to 400 kHz) and high-speed mode (1 kHz to 2.94 MHz).
}
/**
* Read register
* @param deviceId device Id
* @param addr register address
* @returns value read from register
*/
uint32_t I2C_Read(uint32_t devId, uint32_t addr) {
FILE_LOG(logDEBUG2, (" ================================================\n"));
FILE_LOG(logDEBUG2, (" Reading from I2C device 0x%x and reg 0x%x\n", devId, addr));
// device Id mask
uint32_t devIdMask = ((devId << I2C_TFR_CMD_ADDR_OFST) & I2C_TFR_CMD_ADDR_MSK);
FILE_LOG(logDEBUG2, (" devId:0x%x\n", devIdMask));
// write I2C ID
bus_w(I2C_Transfer_Command_Fifo_Reg, (devIdMask & ~(I2C_TFR_CMD_RW_MSK)));
FILE_LOG(logDEBUG2, (" write devID and R/-W:0x%x\n", (devIdMask & ~(I2C_TFR_CMD_RW_MSK))));
// write register addr
bus_w(I2C_Transfer_Command_Fifo_Reg, addr);
FILE_LOG(logDEBUG2, (" write addr:0x%x\n", addr));
// repeated start with read (repeated start needed here because it was in write operation mode earlier, for the device ID)
bus_w(I2C_Transfer_Command_Fifo_Reg, (devIdMask | I2C_TFR_CMD_RPTD_STRT_MSK | I2C_TFR_CMD_RW_READ_VAL));
FILE_LOG(logDEBUG2, (" repeated start:0x%x\n", (devIdMask | I2C_TFR_CMD_RPTD_STRT_MSK | I2C_TFR_CMD_RW_READ_VAL)));
// continue reading
bus_w(I2C_Transfer_Command_Fifo_Reg, 0x0);
FILE_LOG(logDEBUG2, (" continue reading:0x%x\n", 0x0));
// stop reading
bus_w(I2C_Transfer_Command_Fifo_Reg, I2C_TFR_CMD_STOP_MSK);
FILE_LOG(logDEBUG2, (" stop reading:0x%x\n", I2C_TFR_CMD_STOP_MSK));
// read value
uint32_t retval = 0;
//In case one wants to do something more general (INA226 receives only 2 bytes)
// wait till status is idle
int status = 1;
while(status) {
status = bus_r(I2C_Status_Reg) & I2C_STATUS_BUSY_MSK;
FILE_LOG(logDEBUG2, (" status:%d\n", status));
usleep(0);
}
// get rx fifo level (get number of bytes to be received)
int level = bus_r(I2C_Rx_Data_Fifo_Level_Reg);
FILE_LOG(logDEBUG2, (" level:%d\n", level));
int iloop = level - 1;
// level bytes to read, read 1 byte at a time
for (iloop = level - 1; iloop >= 0; --iloop) {
u_int16_t byte = bus_r(I2C_Rx_Data_Fifo_Reg) & I2C_RX_DATA_FIFO_RXDATA_MSK;
FILE_LOG(logDEBUG2, (" byte nr %d:0x%x\n", iloop, byte));
// push by 1 byte at a time
retval |= (byte << (8 * iloop));
}
FILE_LOG(logDEBUG2, (" retval:0x%x\n", retval));
FILE_LOG(logDEBUG2, (" ================================================\n"));
return retval;
}
/**
* Write register (16 bit value)
* @param deviceId device Id
* @param addr register address
* @param data data to be written (16 bit)
*/
void I2C_Write(uint32_t devId, uint32_t addr, uint16_t data) {
FILE_LOG(logDEBUG2, (" ================================================\n"));
FILE_LOG(logDEBUG2, (" Writing to I2C (Device:0x%x, reg:0x%x, data:%d)\n", devId, addr, data));
// device Id mask
uint32_t devIdMask = ((devId << I2C_TFR_CMD_ADDR_OFST) & I2C_TFR_CMD_ADDR_MSK);
FILE_LOG(logDEBUG2, (" devId:0x%x\n", devId));
// write I2C ID
bus_w(I2C_Transfer_Command_Fifo_Reg, (devIdMask & ~(I2C_TFR_CMD_RW_MSK)));
FILE_LOG(logDEBUG2, (" write devID and R/-W:0x%x\n", (devIdMask & ~(I2C_TFR_CMD_RW_MSK))));
// write register addr
bus_w(I2C_Transfer_Command_Fifo_Reg, addr);
FILE_LOG(logDEBUG2, (" write addr:0x%x\n", addr));
// do not do the repeated start as it is already in write operation mode (else it wont work)
uint8_t msb = (uint8_t)((data & 0xFF00) >> 8);
uint8_t lsb = (uint8_t)(data & 0x00FF);
FILE_LOG(logDEBUG2, (" msb:0x%02x, lsb:0x%02x\n", msb, lsb));
// writing data MSB
bus_w(I2C_Transfer_Command_Fifo_Reg, ((msb << I2C_TFR_CMD_DATA_FR_WR_OFST) & I2C_TFR_CMD_DATA_FR_WR_MSK));
FILE_LOG(logDEBUG2, (" write msb:0x%02x\n", ((msb << I2C_TFR_CMD_DATA_FR_WR_OFST) & I2C_TFR_CMD_DATA_FR_WR_MSK)));
// writing data LSB and stop writing bit
bus_w(I2C_Transfer_Command_Fifo_Reg, ((lsb << I2C_TFR_CMD_DATA_FR_WR_OFST) & I2C_TFR_CMD_DATA_FR_WR_MSK) | I2C_TFR_CMD_STOP_MSK);
FILE_LOG(logDEBUG2, (" write lsb and stop writing:0x%x\n", ((lsb << I2C_TFR_CMD_DATA_FR_WR_OFST) & I2C_TFR_CMD_DATA_FR_WR_MSK) | I2C_TFR_CMD_STOP_MSK));
FILE_LOG(logDEBUG2, (" ================================================\n"));
}