ardupilot/libraries/AP_HAL_Linux/RCInput_RPI.cpp

679 lines
24 KiB
C++

#include <AP_HAL/AP_HAL.h>
#if CONFIG_HAL_BOARD_SUBTYPE == HAL_BOARD_SUBTYPE_LINUX_NAVIO || \
CONFIG_HAL_BOARD_SUBTYPE == HAL_BOARD_SUBTYPE_LINUX_ERLEBRAIN2 || \
CONFIG_HAL_BOARD_SUBTYPE == HAL_BOARD_SUBTYPE_LINUX_BH || \
CONFIG_HAL_BOARD_SUBTYPE == HAL_BOARD_SUBTYPE_LINUX_DARK || \
CONFIG_HAL_BOARD_SUBTYPE == HAL_BOARD_SUBTYPE_LINUX_PXFMINI || \
CONFIG_HAL_BOARD_SUBTYPE == HAL_BOARD_SUBTYPE_LINUX_OBAL_V1
#include <assert.h>
#include <errno.h>
#include <fcntl.h>
#include <pthread.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/ioctl.h>
#include <sys/mman.h>
#include <sys/stat.h>
#include <sys/time.h>
#include <sys/types.h>
#include <time.h>
#include <unistd.h>
#include "GPIO.h"
#include "RCInput_RPI.h"
#include "Util_RPI.h"
#ifdef DEBUG
#define debug(fmt, args ...) do { fprintf(stderr,"[RCInput_RPI]: %s:%d: " fmt, __FUNCTION__, __LINE__, ## args); } while (0)
#else
#define debug(fmt, args ...)
#endif
#define PAGE_SIZE (4*1024)
//Parametres
#define RCIN_RPI_BUFFER_LENGTH 4
#define RCIN_RPI_SAMPLE_FREQ 125
#define RCIN_RPI_DMA_CHANNEL 0
#define RCIN_RPI_MAX_SIZE_LINE 50
#define RCIN_RPI_MAX_COUNTER (RCIN_RPI_BUFFER_LENGTH * PAGE_SIZE * 2) // 1 circle_buffer
#if CONFIG_HAL_BOARD_SUBTYPE == HAL_BOARD_SUBTYPE_LINUX_BH
#define RCIN_RPI_SIG_HIGH 0
#define RCIN_RPI_SIG_LOW 1
// Each gpio stands for a rcinput channel,
// the first one in RcChnGpioTbl is channel 1 in receiver
static uint16_t RcChnGpioTbl[RCIN_RPI_CHN_NUM] = {
RPI_GPIO_<5>(), RPI_GPIO_<6>(), RPI_GPIO_<12>(),
RPI_GPIO_<13>(), RPI_GPIO_<19>(), RPI_GPIO_<20>(),
RPI_GPIO_<21>(), RPI_GPIO_<26>()
};
#elif (CONFIG_HAL_BOARD_SUBTYPE == HAL_BOARD_SUBTYPE_LINUX_OBAL_V1)
#define RCIN_RPI_SIG_HIGH 0
#define RCIN_RPI_SIG_LOW 1
static uint16_t RcChnGpioTbl[RCIN_RPI_CHN_NUM] = {
RPI_GPIO_<5>(), RPI_GPIO_<6>(), RPI_GPIO_<13>(),
RPI_GPIO_<19>(), RPI_GPIO_<26>(), RPI_GPIO_<21>(),
RPI_GPIO_<20>(), RPI_GPIO_<16>()
};
#else
#define RCIN_RPI_SIG_HIGH 1
#define RCIN_RPI_SIG_LOW 0
static uint16_t RcChnGpioTbl[RCIN_RPI_CHN_NUM] = {
#if CONFIG_HAL_BOARD_SUBTYPE == HAL_BOARD_SUBTYPE_LINUX_NAVIO
#define PAGE_SIZE (4*1024)
NAVIO_GPIO_PPM_IN
#else
RPI_GPIO_<4>()
#endif
};
#endif // CONFIG_HAL_BOARD_SUBTYPE
//Memory Addresses
#define RCIN_RPI_RPI0_DMA_BASE 0x20007000
#define RCIN_RPI_RPI0_CLK_BASE 0x20101000
#define RCIN_RPI_RPI0_PCM_BASE 0x20203000
#define RCIN_RPI_RPI1_DMA_BASE 0x20007000
#define RCIN_RPI_RPI1_CLK_BASE 0x20101000
#define RCIN_RPI_RPI1_PCM_BASE 0x20203000
#define RCIN_RPI_RPI2_DMA_BASE 0x3F007000
#define RCIN_RPI_RPI2_CLK_BASE 0x3F101000
#define RCIN_RPI_RPI2_PCM_BASE 0x3F203000
#define RCIN_RPI_RPI3_DMA_BASE 0x3F007000
#define RCIN_RPI_RPI3_CLK_BASE 0x3F101000
#define RCIN_RPI_RPI3_PCM_BASE 0x3F203000
#define RCIN_RPI_RPI4_DMA_BASE 0xFE007000
#define RCIN_RPI_RPI4_CLK_BASE 0xFE101000
#define RCIN_RPI_RPI4_PCM_BASE 0xFE203000
#define RCIN_RPI_GPIO_LEV0_ADDR 0x7e200034
#define RCIN_RPI_DMA_LEN 0x1000
#define RCIN_RPI_CLK_LEN 0xA8
#define RCIN_RPI_PCM_LEN 0x24
#define RCIN_RPI_TIMER_BASE 0x7e003004
#define RCIN_RPI_DMA_SRC_INC (1<<8)
#define RCIN_RPI_DMA_DEST_INC (1<<4)
#define RCIN_RPI_DMA_NO_WIDE_BURSTS (1<<26)
#define RCIN_RPI_DMA_WAIT_RESP (1<<3)
#define RCIN_RPI_DMA_D_DREQ (1<<6)
#define RCIN_RPI_DMA_PER_MAP(x) ((x)<<16)
#define RCIN_RPI_DMA_END (1<<1)
#define RCIN_RPI_DMA_RESET (1<<31)
#define RCIN_RPI_DMA_INT (1<<2)
#define RCIN_RPI_DMA_CS (0x00/4)
#define RCIN_RPI_DMA_CONBLK_AD (0x04/4)
#define RCIN_RPI_DMA_DEBUG (0x20/4)
#define RCIN_RPI_PCM_CS_A (0x00/4)
#define RCIN_RPI_PCM_FIFO_A (0x04/4)
#define RCIN_RPI_PCM_MODE_A (0x08/4)
#define RCIN_RPI_PCM_RXC_A (0x0c/4)
#define RCIN_RPI_PCM_TXC_A (0x10/4)
#define RCIN_RPI_PCM_DREQ_A (0x14/4)
#define RCIN_RPI_PCM_INTEN_A (0x18/4)
#define RCIN_RPI_PCM_INT_STC_A (0x1c/4)
#define RCIN_RPI_PCM_GRAY (0x20/4)
#define RCIN_RPI_PCMCLK_CNTL 0x26
#define RCIN_RPI_PCMCLK_DIV 0x27
#define RCIN_RPI_PLL_CLK 50000
/*
* Defaults to 107.14MHz in the firmware setup.
* The PLL channel that used to generate the 100MHz now runs at 750MHz instead of 500,
* so the fw uses 750/7.
* see: https://www.raspberrypi.org/forums/viewtopic.php?t=251902
*/
#define RCIN_RPI4_PLL_CLK 70000
extern const AP_HAL::HAL& hal;
using namespace Linux;
volatile uint32_t *RCInput_RPI::pcm_reg;
volatile uint32_t *RCInput_RPI::clk_reg;
volatile uint32_t *RCInput_RPI::dma_reg;
Memory_table::Memory_table()
{
_page_count = 0;
}
// Init Memory table
Memory_table::Memory_table(uint32_t page_count, int version)
{
uint32_t i;
int fdMem, file;
// Cache coherent adresses depends on RPI's version
uint32_t bus = version == 0 ? 0x40000000 : 0xC0000000;
uint64_t pageInfo;
void *offset;
_virt_pages = (void **)calloc(page_count, sizeof(void *));
_phys_pages = (void **)calloc(page_count, sizeof(void *));
_page_count = page_count;
if ((fdMem = open("/dev/mem", O_RDWR | O_SYNC | O_CLOEXEC)) < 0) {
fprintf(stderr, "Failed to open /dev/mem\n");
printf("Make sure that CONFIG_STRICT_DEVMEM is disabled\n");
exit(-1);
}
if ((file = open("/proc/self/pagemap", O_RDWR | O_SYNC | O_CLOEXEC)) < 0) {
fprintf(stderr, "Failed to open /proc/self/pagemap\n");
exit(-1);
}
// Magic to determine the physical address for this page:
offset = mmap(0, _page_count * PAGE_SIZE, PROT_READ | PROT_WRITE, MAP_SHARED | MAP_ANONYMOUS | MAP_NORESERVE | MAP_LOCKED, -1, 0);
lseek(file, ((uintptr_t)offset) / PAGE_SIZE * 8, SEEK_SET);
// Get list of available cache coherent physical addresses
for (i = 0; i < _page_count; i++) {
_virt_pages[i] = mmap(0, PAGE_SIZE, PROT_READ | PROT_WRITE, MAP_SHARED | MAP_ANONYMOUS | MAP_NORESERVE | MAP_LOCKED, -1, 0);
if (_virt_pages[i] == MAP_FAILED) {
fprintf(stderr, "Failed to map cache coherent physical page (%m)\n");
exit(-1);
}
if (::read(file, &pageInfo, 8) < 8) {
fprintf(stderr, "Failed to read pagemap\n");
exit(-1);
}
_phys_pages[i] = (void *)((uintptr_t)(pageInfo * PAGE_SIZE) | bus);
}
// Map physical addresses to virtual memory
for (i = 0; i < _page_count; i++) {
munmap(_virt_pages[i], PAGE_SIZE);
void * prev_virt = _virt_pages[i];
_virt_pages[i] = mmap(_virt_pages[i], PAGE_SIZE, PROT_READ | PROT_WRITE, MAP_SHARED | MAP_FIXED | MAP_NORESERVE | MAP_LOCKED, fdMem, ((uintptr_t)_phys_pages[i] & (version == 0 ? 0xFFFFFFFFFFFFFFFF : ~bus)));
if (_virt_pages[i] == MAP_FAILED) {
fprintf(stderr, "Failed phys2virt prev_virt=%p phys_page=%p %m\n", prev_virt, _phys_pages[i]);
printf("Make sure that CONFIG_STRICT_DEVMEM is disabled\n");
exit(-1);
}
memset(_virt_pages[i], 0xee, PAGE_SIZE);
}
close(file);
close(fdMem);
}
Memory_table::~Memory_table()
{
free(_virt_pages);
free(_phys_pages);
}
// This function returns physical address with help of pointer, which is offset
// from the beginning of the buffer.
void *Memory_table::get_page(void **const pages, uint32_t addr) const
{
if (addr >= PAGE_SIZE * _page_count) {
return nullptr;
}
return (uint8_t *)pages[(uint32_t)addr / PAGE_SIZE] + addr % PAGE_SIZE;
}
//Get virtual address from the corresponding physical address from memory_table.
void *Memory_table::get_virt_addr(const uint32_t phys_addr) const
{
// FIXME: Can't the address be calculated directly?
// FIXME: if the address room in _phys_pages is not fragmented one may avoid
// a complete loop ..
uint32_t i = 0;
for (; i < _page_count; i++) {
if ((uintptr_t)_phys_pages[i] == (((uintptr_t)phys_addr) & 0xFFFFF000)) {
return (void *)((uintptr_t)_virt_pages[i] + (phys_addr & 0xFFF));
}
}
return nullptr;
}
// This function returns offset from the beginning of the buffer using virtual
// address and memory_table.
uint32_t Memory_table::get_offset(void ** const pages, const uint64_t addr) const
{
uint32_t i = 0;
for (; i < _page_count; i++) {
if ((uintptr_t) pages[i] == (addr & 0xFFFFFFFFFFFFF000) ) {
return (i*PAGE_SIZE + (addr & 0xFFF));
}
}
return -1;
}
// How many bytes are available for reading in circle buffer?
uint32_t Memory_table::bytes_available(const uint32_t read_addr, const uint32_t write_addr) const
{
if (write_addr > read_addr) {
return (write_addr - read_addr);
} else {
return _page_count * PAGE_SIZE - (read_addr - write_addr);
}
}
uint32_t Memory_table::get_page_count() const
{
return _page_count;
}
// Physical addresses of peripheral depends on Raspberry Pi's version
void RCInput_RPI::set_physical_addresses()
{
if (_version == 0) {
// 1 & zero are the same
dma_base = RCIN_RPI_RPI1_DMA_BASE;
clk_base = RCIN_RPI_RPI1_CLK_BASE;
pcm_base = RCIN_RPI_RPI1_PCM_BASE;
} else if (_version == 1 || _version == 2) {
// 2 & 3 are the same
dma_base = RCIN_RPI_RPI2_DMA_BASE;
clk_base = RCIN_RPI_RPI2_CLK_BASE;
pcm_base = RCIN_RPI_RPI2_PCM_BASE;
} else if (_version == 3) {
dma_base = RCIN_RPI_RPI4_DMA_BASE;
clk_base = RCIN_RPI_RPI4_CLK_BASE;
pcm_base = RCIN_RPI_RPI4_PCM_BASE;
} else {
fprintf(stderr,"unknown RPI _version=%i\n", _version);
exit(-1);
}
}
// Map peripheral to virtual memory
void *RCInput_RPI::map_peripheral(uint32_t base, uint32_t len)
{
int fd = open("/dev/mem", O_RDWR | O_CLOEXEC);
void *vaddr;
if (fd < 0) {
printf("Failed to open /dev/mem: %m\n");
printf("Make sure that CONFIG_STRICT_DEVMEM is disabled\n");
return nullptr;
}
vaddr = mmap(nullptr, len, PROT_READ | PROT_WRITE, MAP_SHARED, fd, base);
if (vaddr == MAP_FAILED) {
printf("rpio-pwm: Failed to map peripheral at 0x%08x: %m\n", base);
exit(-1);
}
close(fd);
return vaddr;
}
// Method to init DMA control block
void RCInput_RPI::init_dma_cb(dma_cb_t **cbp, uint32_t mode, uint32_t source, uint32_t dest, uint32_t length, uint32_t stride, uint32_t next_cb)
{
(*cbp)->info = mode;
(*cbp)->src = source;
(*cbp)->dst = dest;
(*cbp)->length = length;
(*cbp)->next = next_cb;
(*cbp)->stride = stride;
}
void RCInput_RPI::stop_dma()
{
dma_reg[RCIN_RPI_DMA_CS | RCIN_RPI_DMA_CHANNEL << 8] = 0;
}
/* We need to be sure that the DMA is stopped upon termination */
void RCInput_RPI::termination_handler(int signum)
{
stop_dma();
AP_HAL::panic("Interrupted: %s", strsignal(signum));
}
// This function is used to init DMA control blocks (setting sampling GPIO
// register, destination adresses, synchronization)
void RCInput_RPI::init_ctrl_data()
{
uint32_t phys_fifo_addr;
uint32_t dest = 0;
uint32_t cbp = 0;
dma_cb_t *cbp_curr;
// Set fifo addr (for delay)
phys_fifo_addr = ((pcm_base + 0x04) & 0x00FFFFFF) | 0x7e000000;
// Init dma control blocks.
/* We are transferring 8 bytes of GPIO register. Every 7th iteration we are
sampling TIMER register, which length is 8 bytes. So, for every 7 samples of GPIO we need
7 * 8 + 8 = 64 bytes of buffer. Value 7 was selected specially to have a 64-byte "block"
TIMER - GPIO. So, we have integer count of such "blocks" at one virtual page. (4096 / 64 = 64
"blocks" per page. As minimum, we must have 2 virtual pages of buffer (to have integer count of
vitual pages for control blocks): for every 7 iterations (64 bytes of buffer) we need 7 control blocks for GPIO
sampling, 7 control blocks for setting frequency and 1 control block for sampling timer, so,
we need 7 + 7 + 1 = 15 control blocks. For integer value, we need 15 pages of control blocks.
Each control block length is 32 bytes. In 15 pages we will have (15 * 4096 / 32) = 15 * 128 control
blocks. 15 * 128 control blocks = 64 * 128 bytes of buffer = 2 pages of buffer.
So, for 7 * 64 * 2 iteration we init DMA for sampling GPIO
and timer to ((7 * 8 + 8) * 64 * 2) = 8192 bytes = 2 pages of buffer.
*/
for (uint32_t i = 0; i < 7 * 128 * RCIN_RPI_BUFFER_LENGTH; i++) {
// Transfer timer every 7th sample
if (i % 7 == 0) {
cbp_curr = (dma_cb_t*)con_blocks->get_page(con_blocks->_virt_pages, cbp);
init_dma_cb(&cbp_curr, RCIN_RPI_DMA_NO_WIDE_BURSTS | RCIN_RPI_DMA_WAIT_RESP , RCIN_RPI_TIMER_BASE,
(uintptr_t)circle_buffer->get_page(circle_buffer->_phys_pages, dest),
8,
0,
(uintptr_t)con_blocks->get_page(con_blocks->_phys_pages,
cbp + sizeof(dma_cb_t)));
dest += 8;
cbp += sizeof(dma_cb_t);
}
// Transfer GPIO (8 bytes)
cbp_curr = (dma_cb_t *)con_blocks->get_page(con_blocks->_virt_pages, cbp);
init_dma_cb(&cbp_curr, RCIN_RPI_DMA_NO_WIDE_BURSTS | RCIN_RPI_DMA_WAIT_RESP, RCIN_RPI_GPIO_LEV0_ADDR,
(uintptr_t)circle_buffer->get_page(circle_buffer->_phys_pages, dest),
8,
0,
(uintptr_t)con_blocks->get_page(con_blocks->_phys_pages,
cbp + sizeof(dma_cb_t)));
dest += 8;
cbp += sizeof(dma_cb_t);
// Delay (for setting sampling frequency)
/* DMA is waiting data request signal (DREQ) from PCM. PCM is set for 1.25 MhZ freqency, so,
each sample of GPIO is limited by writing to PCA queue.
*/
cbp_curr = (dma_cb_t *)con_blocks->get_page(con_blocks->_virt_pages, cbp);
init_dma_cb(&cbp_curr, RCIN_RPI_DMA_NO_WIDE_BURSTS | RCIN_RPI_DMA_WAIT_RESP | RCIN_RPI_DMA_D_DREQ | RCIN_RPI_DMA_PER_MAP(2),
RCIN_RPI_TIMER_BASE, phys_fifo_addr,
4,
0,
(uintptr_t)con_blocks->get_page(con_blocks->_phys_pages,
cbp + sizeof(dma_cb_t)));
cbp += sizeof(dma_cb_t);
}
//Make last control block point to the first (to make circle)
cbp -= sizeof(dma_cb_t);
((dma_cb_t *)con_blocks->get_page(con_blocks->_virt_pages, cbp))->next = (uintptr_t)con_blocks->get_page(con_blocks->_phys_pages, 0);
}
/*Initialise PCM
See BCM2835 documentation:
http://www.raspberrypi.org/wp-content/uploads/2012/02/BCM2835-ARM-Peripherals.pdf
See BCM2711 documentation:
https://datasheets.raspberrypi.org/bcm2711/bcm2711-peripherals.pdf
*/
void RCInput_RPI::init_PCM()
{
pcm_reg[RCIN_RPI_PCM_CS_A] = 1; // Disable Rx+Tx, Enable PCM block
hal.scheduler->delay_microseconds(100);
clk_reg[RCIN_RPI_PCMCLK_CNTL] = 0x5A000006; // Source=PLLD (500MHz)
hal.scheduler->delay_microseconds(100);
if (_version != 3) {
clk_reg[RCIN_RPI_PCMCLK_DIV] = 0x5A000000 | ((RCIN_RPI_PLL_CLK/RCIN_RPI_SAMPLE_FREQ)<<12); // Set pcm div for BCM2835 500MHZ clock. If we need to configure DMA frequency.
}
else {
clk_reg[RCIN_RPI_PCMCLK_DIV] = 0x5A000000 | ((RCIN_RPI4_PLL_CLK/RCIN_RPI_SAMPLE_FREQ)<< 12); // Set pcm div for BCM2711 700MHz clock. If we need to configure DMA frequency.
}
hal.scheduler->delay_microseconds(100);
clk_reg[RCIN_RPI_PCMCLK_CNTL] = 0x5A000016; // Source=PLLD and enable
hal.scheduler->delay_microseconds(100);
pcm_reg[RCIN_RPI_PCM_TXC_A] = 0<<31 | 1<<30 | 0<<20 | 0<<16; // 1 channel, 8 bits
hal.scheduler->delay_microseconds(100);
pcm_reg[RCIN_RPI_PCM_MODE_A] = (10 - 1) << 10; //PCM mode 0b0010010000000000
hal.scheduler->delay_microseconds(100);
pcm_reg[RCIN_RPI_PCM_CS_A] |= 1<<4 | 1<<3; // Clear FIFOs
hal.scheduler->delay_microseconds(100);
pcm_reg[RCIN_RPI_PCM_DREQ_A] = 64<<24 | 64<<8; // DMA Req when one slot is free?
hal.scheduler->delay_microseconds(100);
pcm_reg[RCIN_RPI_PCM_CS_A] |= 1<<9; // Enable DMA
hal.scheduler->delay_microseconds(100);
pcm_reg[RCIN_RPI_PCM_CS_A] |= 1<<2; // Enable Tx
hal.scheduler->delay_microseconds(100);
}
/*Initialise DMA
See BCM2835 documentation:
http://www.raspberrypi.org/wp-content/uploads/2012/02/BCM2835-ARM-Peripherals.pdf
*/
void RCInput_RPI::init_DMA()
{
dma_reg[RCIN_RPI_DMA_CS | RCIN_RPI_DMA_CHANNEL << 8] = RCIN_RPI_DMA_RESET; //Reset DMA
hal.scheduler->delay_microseconds(100);
dma_reg[RCIN_RPI_DMA_CS | RCIN_RPI_DMA_CHANNEL << 8] = RCIN_RPI_DMA_INT | RCIN_RPI_DMA_END;
dma_reg[RCIN_RPI_DMA_CONBLK_AD | RCIN_RPI_DMA_CHANNEL << 8] = reinterpret_cast<uintptr_t>(con_blocks->get_page(con_blocks->_phys_pages, 0));//Set first control block address
dma_reg[RCIN_RPI_DMA_DEBUG | RCIN_RPI_DMA_CHANNEL << 8] = 7; // clear debug error flags
dma_reg[RCIN_RPI_DMA_CS | RCIN_RPI_DMA_CHANNEL << 8] = 0x10880001; // go, mid priority, wait for outstanding writes
}
// We must stop DMA when the process is killed
void RCInput_RPI::set_sigaction()
{
struct sigaction sa, sa_old;
memset(&sa_old, 0, sizeof(sa));
memset(&sa, 0, sizeof(sa));
/* Ignore signals */
sa.sa_handler = SIG_IGN;
sigaction(SIGWINCH, &sa, nullptr);
sigaction(SIGTTOU, &sa, nullptr);
sigaction(SIGTTIN, &sa, nullptr);
/*
* Catch all other signals to ensure DMA is disabled - some of them may
* already be handled elsewhere in cases we consider normal termination.
* In those cases the teardown() method must be called.
*/
for (int i = 0; i < NSIG; i++) {
sigaction(i, nullptr, &sa_old);
if (sa_old.sa_handler == nullptr) {
sa.sa_handler = RCInput_RPI::termination_handler;
sigaction(i, &sa, nullptr);
}
}
}
// Initial setup of variables
RCInput_RPI::RCInput_RPI():
curr_tick_inc(1000/RCIN_RPI_SAMPLE_FREQ),
curr_pointer(0),
curr_channel(0)
{
}
RCInput_RPI::~RCInput_RPI()
{
delete circle_buffer;
delete con_blocks;
}
void RCInput_RPI::teardown()
{
stop_dma();
}
//Initializing necessary registers
void RCInput_RPI::init_registers()
{
dma_reg = (uint32_t *)map_peripheral(dma_base, RCIN_RPI_DMA_LEN);
pcm_reg = (uint32_t *)map_peripheral(pcm_base, RCIN_RPI_PCM_LEN);
clk_reg = (uint32_t *)map_peripheral(clk_base, RCIN_RPI_CLK_LEN);
}
void RCInput_RPI::init()
{
uint64_t signal_states(0);
#if CONFIG_HAL_BOARD_SUBTYPE == HAL_BOARD_SUBTYPE_LINUX_ERLEBRAIN2
_version = 1;
#else
_version = UtilRPI::from(hal.util)->get_rpi_version();
#endif
set_physical_addresses();
// Init memory for buffer and for DMA control blocks.
// See comments in "init_ctrl_data()" to understand values "2" and "15"
circle_buffer = new Memory_table(RCIN_RPI_BUFFER_LENGTH * 2, _version);
con_blocks = new Memory_table(RCIN_RPI_BUFFER_LENGTH * 15, _version);
init_registers();
// Enable PPM or PWM input
for (uint32_t i = 0; i < RCIN_RPI_CHN_NUM; ++i) {
rc_channels[i].enable_pin = hal.gpio->channel(RcChnGpioTbl[i]);
rc_channels[i].enable_pin->mode(HAL_GPIO_INPUT);
}
// Configuration
set_sigaction();
init_ctrl_data();
init_PCM();
init_DMA();
// Wait a bit to let DMA fill queues and come to stable sampling
hal.scheduler->delay(300);
// Reading first sample
curr_tick = *((uint64_t *)circle_buffer->get_page(circle_buffer->_virt_pages, curr_pointer));
curr_pointer += 8;
signal_states = *((uint64_t *)circle_buffer->get_page(circle_buffer->_virt_pages, curr_pointer));
for (uint32_t i = 0; i < RCIN_RPI_CHN_NUM; ++i) {
rc_channels[i].prev_tick = curr_tick;
rc_channels[i].curr_signal = (signal_states & (1 << RcChnGpioTbl[i])) ? RCIN_RPI_SIG_HIGH
: RCIN_RPI_SIG_LOW;
rc_channels[i].last_signal = rc_channels[i].curr_signal;
}
curr_pointer += 8;
set_num_channels(RCIN_RPI_CHN_NUM);
_initialized = true;
}
// Processing signal
void RCInput_RPI::_timer_tick()
{
uint32_t counter = 0;
uint64_t signal_states(0);
if (!_initialized) {
return;
}
// Now we are getting address in which DMAC is writing at current moment
dma_cb_t *ad = (dma_cb_t *)con_blocks->get_virt_addr(dma_reg[RCIN_RPI_DMA_CONBLK_AD | RCIN_RPI_DMA_CHANNEL << 8]);
if (!ad) {
debug("DMA sampling stopped, restarting...\n");
init_ctrl_data();
init_PCM();
init_DMA();
return;
}
const uint32_t offset = con_blocks->get_offset(con_blocks->_virt_pages,(uintptr_t)ad);
for (int j = 1; j >= -1; j--) {
// Get address of next or previous (dma_cb_t)
ad = (dma_cb_t *)con_blocks->get_page(con_blocks->_virt_pages,offset + (uint32_t)(sizeof(dma_cb_t) * j));
if (!ad)
{
continue ;
}
void *x = circle_buffer->get_virt_addr((ad)->dst);
if (x != nullptr) {
counter = circle_buffer->bytes_available(curr_pointer,
circle_buffer->get_offset(circle_buffer->_virt_pages, (uintptr_t)x));
break;
}
}
if (counter == 0) {
return;
}
// How many bytes have DMA transferred (and we can process)?
// We can't stay in method for a long time, because it may lead to delays
if (counter > RCIN_RPI_MAX_COUNTER) {
debug("%5d sample(s) dropped\n", (counter - RCIN_RPI_MAX_COUNTER) / 0x8);
counter = RCIN_RPI_MAX_COUNTER;
}
// Processing ready bytes
for (;counter > 0x40;) {
// Is it timer sample?
if (curr_pointer % (64) == 0) {
curr_tick = *((uint64_t *)circle_buffer->get_page(circle_buffer->_virt_pages, curr_pointer));
curr_pointer += 8;
counter -= 8;
}
// Reading required bit
signal_states = *((uint64_t *)circle_buffer->get_page(circle_buffer->_virt_pages, curr_pointer));
for (uint32_t i = 0; i < RCIN_RPI_CHN_NUM; ++i) {
rc_channels[i].curr_signal = (signal_states & (1 << RcChnGpioTbl[i])) ? RCIN_RPI_SIG_HIGH
: RCIN_RPI_SIG_LOW;
// If the signal changed
if (rc_channels[i].curr_signal != rc_channels[i].last_signal) {
rc_channels[i].delta_time = curr_tick - rc_channels[i].prev_tick;
rc_channels[i].prev_tick = curr_tick;
switch (rc_channels[i].state) {
case RCIN_RPI_INITIAL_STATE:
rc_channels[i].state = RCIN_RPI_ZERO_STATE;
break;
case RCIN_RPI_ZERO_STATE:
if (rc_channels[i].curr_signal == 0) {
rc_channels[i].width_s0 = (uint16_t)rc_channels[i].delta_time;
rc_channels[i].state = RCIN_RPI_ONE_STATE;
}
break;
case RCIN_RPI_ONE_STATE:
if (rc_channels[i].curr_signal == 1) {
rc_channels[i].width_s1 = (uint16_t)rc_channels[i].delta_time;
rc_channels[i].state = RCIN_RPI_ZERO_STATE;
if (1 == RCIN_RPI_CHN_NUM) {
_process_rc_pulse(rc_channels[i].width_s0,
rc_channels[i].width_s1);
}
else {
_process_pwm_pulse(i, rc_channels[i].width_s0,
rc_channels[i].width_s1);
}
}
break;
}
}
rc_channels[i].last_signal = rc_channels[i].curr_signal;
}
curr_pointer += 8;
counter -= 8;
if (curr_pointer >= circle_buffer->get_page_count() * PAGE_SIZE) {
curr_pointer = 0;
}
curr_tick += curr_tick_inc;
}
}
#endif // CONFIG_HAL_BOARD_SUBTYPE