mirror of
https://github.com/betaflight/betaflight.git
synced 2025-07-13 11:29:58 +03:00
PICO bus_spi_pico changes - work in progress...
Testing w/o DMA Fix SPI_SPEED_20MHZ Add GPIO pin ranges Initial implementation of spiInternalInitStream and spiSequenceStart (mode, speed set up, based on STM32/bus_spi_ll.c) spiCalculateDivider records numbers as calculated in pico-sdk spi_set_baudrate, for use later in spiCalculateClock.
This commit is contained in:
Matthew Selby
parent
17ac3d9895
commit
de04ac1f11
1 changed files with 220 additions and 15 deletions
|
|
@ -19,6 +19,13 @@
|
|||
* If not, see <http://www.gnu.org/licenses/>.
|
||||
*/
|
||||
|
||||
/*
|
||||
* Clock divider code based on pico-sdk/src/rp2_common/hardware_spi.c
|
||||
* Copyright (c) 2020 Raspberry Pi (Trading) Ltd.
|
||||
*
|
||||
* SPDX-License-Identifier: BSD-3-Clause
|
||||
*/
|
||||
|
||||
#include <stdbool.h>
|
||||
#include <stdint.h>
|
||||
#include <string.h>
|
||||
|
|
@ -26,6 +33,7 @@
|
|||
#include "platform.h"
|
||||
|
||||
#ifdef USE_SPI
|
||||
#define TESTING_NO_DMA 1
|
||||
|
||||
#include "common/maths.h"
|
||||
#include "drivers/bus.h"
|
||||
|
|
@ -43,29 +51,43 @@
|
|||
|
||||
#include "pg/bus_spi.h"
|
||||
|
||||
#define SPI_SPEED_20MHZ 2000000
|
||||
#define SPI_SPEED_20MHZ 20000000
|
||||
#define SPI_DATAWIDTH 8
|
||||
#define SPI_DMA_THRESHOLD 8
|
||||
|
||||
const spiHardware_t spiHardware[] = {
|
||||
#ifdef RP2350B
|
||||
{
|
||||
.device = SPIDEV_0,
|
||||
.reg = SPI0,
|
||||
.sckPins = {
|
||||
{ DEFIO_TAG_E(P2) },
|
||||
{ DEFIO_TAG_E(P6) },
|
||||
{ DEFIO_TAG_E(P18) },
|
||||
{ DEFIO_TAG_E(P22) },
|
||||
#ifdef RP2350B
|
||||
{ DEFIO_TAG_E(P34) },
|
||||
{ DEFIO_TAG_E(P38) },
|
||||
#endif
|
||||
},
|
||||
.misoPins = {
|
||||
{ DEFIO_TAG_E(P0) },
|
||||
{ DEFIO_TAG_E(P4) },
|
||||
{ DEFIO_TAG_E(P16) },
|
||||
{ DEFIO_TAG_E(P20) },
|
||||
#ifdef RP2350B
|
||||
{ DEFIO_TAG_E(P32) },
|
||||
{ DEFIO_TAG_E(P36) },
|
||||
#endif
|
||||
},
|
||||
.mosiPins = {
|
||||
{ DEFIO_TAG_E(P3) },
|
||||
{ DEFIO_TAG_E(P7) },
|
||||
{ DEFIO_TAG_E(P19) },
|
||||
{ DEFIO_TAG_E(P23) },
|
||||
#ifdef RP2350B
|
||||
{ DEFIO_TAG_E(P35) },
|
||||
{ DEFIO_TAG_E(P39) },
|
||||
#endif
|
||||
},
|
||||
},
|
||||
{
|
||||
|
|
@ -74,17 +96,34 @@ const spiHardware_t spiHardware[] = {
|
|||
.sckPins = {
|
||||
{ DEFIO_TAG_E(P10) },
|
||||
{ DEFIO_TAG_E(P14) },
|
||||
{ DEFIO_TAG_E(P26) },
|
||||
#ifdef RP2350B
|
||||
{ DEFIO_TAG_E(P30) },
|
||||
{ DEFIO_TAG_E(P42) },
|
||||
{ DEFIO_TAG_E(P46) },
|
||||
#endif
|
||||
},
|
||||
.misoPins = {
|
||||
{ DEFIO_TAG_E(P8) },
|
||||
{ DEFIO_TAG_E(P12) },
|
||||
{ DEFIO_TAG_E(P24) },
|
||||
{ DEFIO_TAG_E(P28) },
|
||||
#ifdef RP2350B
|
||||
{ DEFIO_TAG_E(P40) },
|
||||
{ DEFIO_TAG_E(P44) },
|
||||
#endif
|
||||
},
|
||||
.mosiPins = {
|
||||
{ DEFIO_TAG_E(P11) },
|
||||
{ DEFIO_TAG_E(P15) },
|
||||
{ DEFIO_TAG_E(P27) },
|
||||
#ifdef RP2350B
|
||||
{ DEFIO_TAG_E(P31) },
|
||||
{ DEFIO_TAG_E(P43) },
|
||||
{ DEFIO_TAG_E(P47) },
|
||||
#endif
|
||||
},
|
||||
},
|
||||
#endif
|
||||
};
|
||||
|
||||
void spiPinConfigure(const struct spiPinConfig_s *pConfig)
|
||||
|
|
@ -118,7 +157,8 @@ void spiPinConfigure(const struct spiPinConfig_s *pConfig)
|
|||
}
|
||||
}
|
||||
|
||||
static spi_inst_t *getSpiInstanceByDevice(SPI0_Type *spi)
|
||||
/*
|
||||
static spi_inst_t *getSpiInstanceByDevice(SPI_TypeDef *spi)
|
||||
{
|
||||
if (spi == SPI0) {
|
||||
return spi0;
|
||||
|
|
@ -127,28 +167,97 @@ static spi_inst_t *getSpiInstanceByDevice(SPI0_Type *spi)
|
|||
}
|
||||
return NULL;
|
||||
}
|
||||
*/
|
||||
|
||||
static void spiSetClockFromSpeed(spi_inst_t *spi, uint16_t speed)
|
||||
{
|
||||
uint32_t freq = spiCalculateClock(speed);
|
||||
spi_set_baudrate(spi, freq);
|
||||
}
|
||||
|
||||
/*
|
||||
|
||||
enum spi_cpha_t { SPI_CPHA_0 = 0, SPI_CPHA_1 = 1 }
|
||||
Enumeration of SPI CPHA (clock phase) values.
|
||||
|
||||
enum spi_cpol_t { SPI_CPOL_0 = 0, SPI_CPOL_1 = 1 }
|
||||
Enumeration of SPI CPOL (clock polarity) values.
|
||||
|
||||
enum spi_order_t { SPI_LSB_FIRST = 0, SPI_MSB_FIRST = 1 }
|
||||
Enumeration of SPI bit-order values.
|
||||
|
||||
|
||||
static void spi_set_format (spi_inst_t * spi, uint data_bits, spi_cpol_t cpol, spi_cpha_t cpha, __unused spi_order_t order) [inline], [static]
|
||||
|
||||
Configure SPI.
|
||||
|
||||
Configure how the SPI serialises and deserialises data on the wire
|
||||
|
||||
Parameters
|
||||
|
||||
spi
|
||||
SPI instance specifier, either spi0 or spi1
|
||||
|
||||
data_bits
|
||||
Number of data bits per transfer. Valid values 4..16.
|
||||
|
||||
cpol
|
||||
SSPCLKOUT polarity, applicable to Motorola SPI frame format only.
|
||||
|
||||
cpha
|
||||
SSPCLKOUT phase, applicable to Motorola SPI frame format only
|
||||
|
||||
order
|
||||
Must be SPI_MSB_FIRST, no other values supported on the PL022
|
||||
|
||||
|
||||
*/
|
||||
|
||||
|
||||
void spiInitDevice(SPIDevice device)
|
||||
{
|
||||
// maybe here set getSpiInstanceByDevice(spi->dev) SPI device with
|
||||
// settings like
|
||||
// STM does
|
||||
//SetRXFIFOThreshold ...QF (1/4 full presumably)
|
||||
// Init -> full duplex, master, 8biut, baudrate, MSBfirst, no CRC,
|
||||
// Clock = PolarityHigh, Phase_2Edge
|
||||
|
||||
|
||||
const spiDevice_t *spi = &spiDevice[device];
|
||||
|
||||
if (!spi->dev) {
|
||||
return;
|
||||
}
|
||||
|
||||
spi_init(getSpiInstanceByDevice(spi->dev), SPI_SPEED_20MHZ);
|
||||
spi_init(SPI_INST(spi->dev), SPI_SPEED_20MHZ);
|
||||
|
||||
gpio_set_function(IO_PINBYTAG(spi->miso), GPIO_FUNC_SPI);
|
||||
gpio_set_function(IO_PINBYTAG(spi->mosi), GPIO_FUNC_SPI);
|
||||
gpio_set_function(IO_PINBYTAG(spi->sck), GPIO_FUNC_SPI);
|
||||
}
|
||||
|
||||
void spiInitBusDMA(void)
|
||||
{
|
||||
//TODO: implement
|
||||
// if required to set up mappings of peripherals to DMA instances?
|
||||
// can just start off with dma_claim_unused_channel in spiInternalInitStream?
|
||||
}
|
||||
|
||||
void spiInternalResetStream(dmaChannelDescriptor_t *descriptor)
|
||||
{
|
||||
//TODO: implement
|
||||
UNUSED(descriptor);
|
||||
}
|
||||
|
||||
bool spiInternalReadWriteBufPolled(SPI_TypeDef *instance, const uint8_t *txData, uint8_t *rxData, int len)
|
||||
{
|
||||
// TODO optimise with 16-bit transfers as per stm bus_spi_ll code
|
||||
int bytesProcessed = spi_write_read_blocking(SPI_INST(instance), txData, rxData, len);
|
||||
return bytesProcessed == len;
|
||||
}
|
||||
|
||||
// Initialise DMA before first segment transfer
|
||||
void spiInternalInitStream(const extDevice_t *dev, bool preInit)
|
||||
{
|
||||
UNUSED(preInit);
|
||||
|
|
@ -159,7 +268,7 @@ void spiInternalInitStream(const extDevice_t *dev, bool preInit)
|
|||
dev->bus->dmaTx->channel = dma_tx;
|
||||
dev->bus->dmaRx->channel = dma_rx;
|
||||
dev->bus->dmaTx->irqHandlerCallback = NULL;
|
||||
dev->bus->dmaRx->irqHandlerCallback = spiInternalResetStream;
|
||||
dev->bus->dmaRx->irqHandlerCallback = spiInternalResetStream; // TODO: implement - correct callback
|
||||
|
||||
const spiDevice_t *spi = &spiDevice[spiDeviceByInstance(dev->bus->busType_u.spi.instance)];
|
||||
dma_channel_config config = dma_channel_get_default_config(dma_tx);
|
||||
|
|
@ -175,10 +284,12 @@ void spiInternalInitStream(const extDevice_t *dev, bool preInit)
|
|||
dma_channel_configure(dma_rx, &config, dev->rxBuf, &spi_get_hw(SPI_INST(spi->dev))->dr, 0, false);
|
||||
}
|
||||
|
||||
// Start DMA transfer for the current segment
|
||||
void spiInternalStartDMA(const extDevice_t *dev)
|
||||
{
|
||||
dma_channel_set_trans_count(dev->bus->dmaTx->channel, dev->bus->curSegment->len + 1, false);
|
||||
dma_channel_set_trans_count(dev->bus->dmaRx->channel, dev->bus->curSegment->len + 1, false);
|
||||
// TODO check correct, was len + 1 now len
|
||||
dma_channel_set_trans_count(dev->bus->dmaTx->channel, dev->bus->curSegment->len, false);
|
||||
dma_channel_set_trans_count(dev->bus->dmaRx->channel, dev->bus->curSegment->len, false);
|
||||
|
||||
dma_channel_start(dev->bus->dmaTx->channel);
|
||||
dma_channel_start(dev->bus->dmaRx->channel);
|
||||
|
|
@ -188,18 +299,112 @@ void spiInternalStartDMA(const extDevice_t *dev)
|
|||
void spiSequenceStart(const extDevice_t *dev)
|
||||
{
|
||||
//TODO: implementation for PICO
|
||||
UNUSED(dev);
|
||||
// base on STM32/bus_spi_ll.c
|
||||
|
||||
busDevice_t *bus = dev->bus;
|
||||
SPI_TypeDef *instance = bus->busType_u.spi.instance;
|
||||
spiDevice_t *spi = &spiDevice[spiDeviceByInstance(instance)];
|
||||
bool dmaSafe = dev->useDMA;
|
||||
#if TESTING_NO_DMA
|
||||
dmaSafe = false;
|
||||
#endif
|
||||
uint32_t xferLen = 0;
|
||||
uint32_t segmentCount = 0;
|
||||
|
||||
//
|
||||
bus->initSegment = true;
|
||||
|
||||
|
||||
// Switch bus speed
|
||||
if (dev->busType_u.spi.speed != bus->busType_u.spi.speed) {
|
||||
spiSetClockFromSpeed(SPI_INST(instance), dev->busType_u.spi.speed);
|
||||
bus->busType_u.spi.speed = dev->busType_u.spi.speed;
|
||||
}
|
||||
|
||||
// Switch SPI clock polarity/phase if necessary
|
||||
if (dev->busType_u.spi.leadingEdge != bus->busType_u.spi.leadingEdge) {
|
||||
uint8_t sckPin = IO_PINBYTAG(spi->sck);
|
||||
gpio_set_slew_rate(sckPin, GPIO_SLEW_RATE_FAST);
|
||||
// Betaflight busDevice / SPI supports modes 0 (leadingEdge True), 3 (leadingEdge False)
|
||||
// 0: (CPOL 0, CPHA 0)
|
||||
// 3: (CPOL 1, CPHA 1)
|
||||
if (dev->busType_u.spi.leadingEdge) {
|
||||
spi_set_format(SPI_INST(instance), SPI_DATAWIDTH, SPI_CPOL_0, SPI_CPHA_0, SPI_MSB_FIRST);
|
||||
}
|
||||
else {
|
||||
spi_set_format(SPI_INST(instance), SPI_DATAWIDTH, SPI_CPOL_1, SPI_CPHA_1, SPI_MSB_FIRST);
|
||||
}
|
||||
|
||||
bus->busType_u.spi.leadingEdge = dev->busType_u.spi.leadingEdge;
|
||||
}
|
||||
|
||||
// NB for RP2350 targets, heap and stack will be in SRAM (single-cycle),
|
||||
// so there are no cache issues with DMA.
|
||||
for (busSegment_t *checkSegment = (busSegment_t *)bus->curSegment; checkSegment->len; checkSegment++) {
|
||||
segmentCount++;
|
||||
xferLen += checkSegment->len;
|
||||
}
|
||||
|
||||
// Use DMA if possible
|
||||
// If there are more than one segments, or a single segment with negateCS negated in the list terminator then force DMA irrespective of length
|
||||
if (bus->useDMA && dmaSafe && ((segmentCount > 1) ||
|
||||
(xferLen >= SPI_DMA_THRESHOLD) ||
|
||||
!bus->curSegment[segmentCount].negateCS)) {
|
||||
spiProcessSegmentsDMA(dev);
|
||||
} else {
|
||||
spiProcessSegmentsPolled(dev);
|
||||
}
|
||||
}
|
||||
|
||||
uint16_t spiCalculateDivider(uint32_t freq)
|
||||
{
|
||||
/*
|
||||
Divider is probably not needed for the PICO as the baud rate on the
|
||||
SPI bus can be set directly.
|
||||
SPI clock is set in Betaflight code by calling spiSetClkDivisor, which records a uint16_t value into a .speed field.
|
||||
In order to maintain this code (for simplicity), record the prescale and postdiv numbers as calculated in
|
||||
pico-sdk/src/rp2_common/hardware_spi.c: spi_set_baudrate()
|
||||
|
||||
In anycase max SPI clock is half the system clock frequency.
|
||||
Therefore the minimum divider is 2.
|
||||
prescale and postdiv are in range 1..255 and are packed into the return value.
|
||||
*/
|
||||
return MAX(2, (((clock_get_hz(clk_sys) + (freq / 2)) / freq) + 1) & ~1);
|
||||
|
||||
uint32_t spiClock = clock_get_hz(clk_peri);
|
||||
uint32_t prescale, postdiv;
|
||||
// Find smallest prescale value which puts output frequency in range of
|
||||
// post-divide. Prescale is an even number from 2 to 254 inclusive.
|
||||
for (prescale = 2; prescale <= 254; prescale += 2) {
|
||||
if (spiClock < prescale * 256 * (uint64_t) freq)
|
||||
break;
|
||||
}
|
||||
if (prescale > 254) {
|
||||
prescale = 254;
|
||||
}
|
||||
|
||||
// Find largest post-divide which makes output <= freq. Post-divide is
|
||||
// an integer in the range 1 to 256 inclusive.
|
||||
for (postdiv = 256; postdiv > 1; --postdiv) {
|
||||
if (spiClock / (prescale * (postdiv - 1)) > freq)
|
||||
break;
|
||||
}
|
||||
|
||||
// Store prescale, (postdiv - 1), both in range 0 to 255.
|
||||
return (uint16_t)((prescale << 8) + (postdiv - 1));
|
||||
}
|
||||
|
||||
uint32_t spiCalculateClock(uint16_t speed)
|
||||
{
|
||||
/*
|
||||
speed contains packed values of prescale and postdiv.
|
||||
Retrieve a frequency which will recreate the same prescale and postdiv on a call to spi_set_baudrate().
|
||||
*/
|
||||
uint32_t spiClock = clock_get_hz(clk_peri);
|
||||
uint32_t prescale = speed >> 8;
|
||||
uint32_t postdivMinusOne = speed & 0xFF;
|
||||
|
||||
// Set freq to reverse the calculation, so that we would end up with the same prescale and postdiv,
|
||||
// hence the same frequency as if we had requested directly from spiCalculateDivider().
|
||||
uint32_t freq = 1 + (spiClock/prescale)/(postdivMinusOne + 1);
|
||||
|
||||
return freq;
|
||||
}
|
||||
|
||||
|
||||
#endif
|
||||
|
|
|
|||
Loading…
Add table
Add a link
Reference in a new issue