ardupilot/libraries/SITL/SIM_RAMTRON.cpp

112 lines
3.3 KiB
C++

#include "SIM_RAMTRON.h"
#include <errno.h>
#include <unistd.h>
#include <AP_HAL_SITL/AP_HAL_SITL.h>
using namespace SITL;
extern HAL_SITL& hal;
void RAMTRON::open_storage_fd()
{
if (storage_fd != -1) {
AP_HAL::panic("Should not have been called");
}
const char *filepath = filename();
uint32_t flags = O_RDWR|O_CREAT;
if (hal.get_wipe_storage()) {
flags |= O_TRUNC;
}
storage_fd = open(filepath, flags, 0644);
if (storage_fd == -1) {
AP_HAL::panic("open(%s): %s", filepath, strerror(errno));
}
if (ftruncate(storage_fd, storage_size()) != 0) {
AP_HAL::panic("truncate(%s): %s", filepath, strerror(errno));
}
}
int RAMTRON::rdwr(uint8_t count, SPI::spi_ioc_transfer *&tfrs)
{
if (storage_fd == -1) {
open_storage_fd();
}
// commands:
static const uint8_t RAMTRON_RDID = 0x9f;
static const uint8_t RAMTRON_READ = 0x03;
static const uint8_t RAMTRON_WREN = 0x06;
static const uint8_t RAMTRON_WRITE = 0x02;
for (uint8_t i=0; i<count; i++) {
SPI::spi_ioc_transfer &tfr = tfrs[i];
uint8_t *tx_buf = (uint8_t*)(tfr.tx_buf);
uint8_t *rx_buf = (uint8_t*)(tfr.rx_buf);
switch (state) {
case State::WAITING: {
// find a command
uint8_t command = tx_buf[0];
switch (command) {
case RAMTRON_RDID:
state = State::READING_RDID;
break;
case RAMTRON_READ:
xfr_addr = tx_buf[1] << 8 | tx_buf[2];
state = State::READING;
break;
case RAMTRON_WRITE:
xfr_addr = tx_buf[1] << 8 | tx_buf[2];
state = State::WRITING;
break;
case RAMTRON_WREN:
write_enabled = true;
break;
default:
abort();
}
break;
}
case State::READING_RDID:
fill_rdid(rx_buf, tfr.len);
state = State::WAITING;
break;
case State::READING: {
if (xfr_addr + tfr.len > storage_size()) {
abort();
}
if (lseek(storage_fd, xfr_addr, SEEK_SET) == -1) {
AP_HAL::panic("lseek(): %s", strerror(errno));
}
const size_t read_ret = read(storage_fd, rx_buf, tfr.len);
if (read_ret != tfr.len) {
AP_HAL::panic("read(): %s (%d/%u)", strerror(errno), (signed)read_ret, (unsigned)tfr.len);
}
state = State::WAITING;
break;
}
case State::WRITING: {
if (!write_enabled) {
AP_HAL::panic("Writes not enabled");
}
if (xfr_addr + tfr.len > storage_size()) {
abort();
}
if (lseek(storage_fd, xfr_addr, SEEK_SET) == -1) {
AP_HAL::panic("lseek(): %s", strerror(errno));
}
const size_t write_ret = write(storage_fd, tx_buf, tfr.len);
if (write_ret != tfr.len) {
AP_HAL::panic("write(): %s (%d/%u)", strerror(errno), (signed)write_ret, (unsigned)tfr.len);
}
state = State::WAITING;
write_enabled = false;
break;
}
}
}
return 0;
}