zephyr/drivers/spi/spis_nrf5_legacy.c

457 lines
13 KiB
C

/* spis_nrf5.c - SPI slave driver for Nordic nRF5x SoCs */
/*
* Copyright (c) 2016, 2017 Linaro Limited.
*
* SPDX-License-Identifier: Apache-2.0
*/
#define SYS_LOG_LEVEL CONFIG_SYS_LOG_SPI_LEVEL
#include <device.h>
#include <errno.h>
#include <logging/sys_log.h>
#include <sys_io.h>
#include <board.h>
#include <init.h>
#include <gpio.h>
#include <spi.h>
#include <nrf.h>
#include <toolchain.h>
typedef void (*spis_nrf5_config_t)(void);
struct spis_nrf5_config {
NRF_SPIS_Type *regs; /* Registers */
spis_nrf5_config_t config_func; /* IRQ config func pointer */
u8_t sck_pin; /* SCK GPIO pin number */
u8_t mosi_pin; /* MOSI GPIO pin number */
u8_t miso_pin; /* MISO GPIO pin number */
u8_t csn_pin; /* CSN GPIO pin number */
u8_t def; /* Default character */
};
struct spis_nrf5_data {
u8_t error;
struct k_sem device_sync_sem; /* synchronisation semaphore */
};
#define DEV_CFG(dev) \
((const struct spis_nrf5_config * const)(dev)->config->config_info)
#define DEV_DATA(dev) \
((struct spis_nrf5_data * const)(dev)->driver_data)
#define SPI_REGS(dev) \
((DEV_CFG(dev))->regs)
/* Register fields */
#define NRF5_SPIS_SHORTCUT_END_ACQUIRE \
(SPIS_SHORTS_END_ACQUIRE_Enabled << SPIS_SHORTS_END_ACQUIRE_Pos)
#define NRF5_SPIS_ORDER_MSB \
(SPIS_CONFIG_ORDER_MsbFirst << SPIS_CONFIG_ORDER_Pos)
#define NRF5_SPIS_ORDER_LSB \
(SPIS_CONFIG_ORDER_LsbFirst << SPIS_CONFIG_ORDER_Pos)
#define NRF5_SPIS_CPHA_LEADING \
(SPIS_CONFIG_CPHA_Leading << SPIS_CONFIG_CPHA_Pos)
#define NRF5_SPIS_CPHA_TRAILING \
(SPIS_CONFIG_CPHA_Trailing << SPIS_CONFIG_CPHA_Pos)
#define NRF5_SPIS_CPOL_HIGH \
(SPIS_CONFIG_CPOL_ActiveHigh << SPIS_CONFIG_CPOL_Pos)
#define NRF5_SPIS_CPOL_LOW \
(SPIS_CONFIG_CPOL_ActiveLow << SPIS_CONFIG_CPOL_Pos)
#define NRF5_SPIS_ENABLED \
(SPIS_ENABLE_ENABLE_Enabled << SPIS_ENABLE_ENABLE_Pos)
#define NRF5_SPIS_CSN_DISABLED_CFG 0xff /* CS disabled value from Kconfig */
#if defined(CONFIG_SOC_SERIES_NRF51X)
#define NRF5_SPIS_CSN_DISABLED (~0U) /* CS disabled register value */
#elif defined(CONFIG_SOC_SERIES_NRF52X)
#define NRF5_SPIS_CSN_DISABLED (1U << 31) /* CS disabled register value */
#endif
static inline bool is_buf_in_ram(const void *buf)
{
return ((((uintptr_t) buf) & 0xE0000000) == 0x20000000);
}
static void spis_nrf5_print_cfg_registers(struct device *dev)
{
__unused NRF_SPIS_Type *regs = SPI_REGS(dev);
__unused u32_t sck, miso, mosi, csn;
__unused u32_t rxd_ptr, rxd_max, rxd_amount;
__unused u32_t txd_ptr, txd_max, txd_amount;
#if defined(CONFIG_SOC_SERIES_NRF51X)
sck = regs->PSELSCK;
miso = regs->PSELMISO;
mosi = regs->PSELMOSI;
csn = regs->PSELCSN;
rxd_ptr = regs->RXDPTR;
rxd_max = regs->MAXRX;
rxd_amount = regs->AMOUNTRX;
txd_ptr = regs->TXDPTR;
txd_max = regs->MAXTX;
txd_amount = regs->AMOUNTTX;
#elif defined(CONFIG_SOC_SERIES_NRF52X)
sck = regs->PSEL.SCK;
miso = regs->PSEL.MISO;
mosi = regs->PSEL.MOSI;
csn = regs->PSEL.CSN;
rxd_ptr = regs->RXD.PTR;
rxd_max = regs->RXD.MAXCNT;
rxd_amount = regs->RXD.AMOUNT;
txd_ptr = regs->TXD.PTR;
txd_max = regs->TXD.MAXCNT;
txd_amount = regs->TXD.AMOUNT;
#endif /* defined(CONFIG_SOC_SERIES_NRF51X) */
SYS_LOG_DBG("\n"
"SHORTS: %x, IRQ: %x, SEMSTAT: %x\n"
"CONFIG: %x, STATUS: %x, ENABLE: %x\n"
"SCKPIN: %x, MISOPIN: %x, MOSIPIN: %x, CSNPIN: %x\n"
"RXD (PTR: %x, MAX: %x, AMOUNT: %x)\n"
"TXD (PTR: %x, MAX: %x, AMOUNT: %x)",
regs->SHORTS, regs->INTENSET, regs->SEMSTAT,
regs->CONFIG, regs->STATUS, regs->ENABLE,
sck, miso, mosi, csn,
rxd_ptr, rxd_max, rxd_amount,
txd_ptr, txd_max, txd_amount);
}
/**
* @brief Configure the SPI host controller for operating against slaves
* @param dev Pointer to the device structure for the driver instance
* @param config Pointer to the application provided configuration
*
* @return 0 if successful, another DEV_* code otherwise.
*/
static int spis_nrf5_configure(struct device *dev, struct spi_config *config)
{
NRF_SPIS_Type *spi_regs = SPI_REGS(dev);
u32_t flags;
/* make sure module is disabled */
spi_regs->ENABLE = 0;
/* TODO: Muck with IRQ priority if needed */
/* Clear any pending events */
spi_regs->EVENTS_ACQUIRED = 0;
spi_regs->EVENTS_ENDRX = 0;
spi_regs->EVENTS_END = 0;
spi_regs->INTENCLR = 0xFFFFFFFF; /* do we need to clear INT ?*/
spi_regs->SHORTS = NRF5_SPIS_SHORTCUT_END_ACQUIRE;
spi_regs->INTENSET |= (SPIS_INTENSET_ACQUIRED_Msk |
SPIS_INTENSET_END_Msk);
/* default transmit and over-read characters */
spi_regs->DEF = DEV_CFG(dev)->def;
spi_regs->ORC = 0x000000AA;
/* user configuration */
flags = config->config;
if (flags & SPI_TRANSFER_LSB) {
spi_regs->CONFIG = NRF5_SPIS_ORDER_LSB;
} else {
spi_regs->CONFIG = NRF5_SPIS_ORDER_MSB;
}
if (flags & SPI_MODE_CPHA) {
spi_regs->CONFIG |= NRF5_SPIS_CPHA_TRAILING;
} else {
spi_regs->CONFIG |= NRF5_SPIS_CPHA_LEADING;
}
if (flags & SPI_MODE_CPOL) {
spi_regs->CONFIG |= NRF5_SPIS_CPOL_LOW;
} else {
spi_regs->CONFIG |= NRF5_SPIS_CPOL_HIGH;
}
/* Enable the SPIS - peripherals sharing same ID will be disabled */
spi_regs->ENABLE = NRF5_SPIS_ENABLED;
spis_nrf5_print_cfg_registers(dev);
SYS_LOG_DBG("SPI Slave Driver configured");
return 0;
}
/**
* @brief Read and/or write a defined amount of data through an SPI driver
*
* @param dev Pointer to the device structure for the driver instance
* @param tx_buf Memory buffer that data should be transferred from
* @param tx_buf_len Size of the memory buffer available for reading from
* @param rx_buf Memory buffer that data should be transferred to
* @param rx_buf_len Size of the memory buffer available for writing to
*
* @return 0 if successful, another DEV_* code otherwise.
*/
static int spis_nrf5_transceive(struct device *dev, const void *tx_buf,
u32_t tx_buf_len, void *rx_buf, u32_t rx_buf_len)
{
NRF_SPIS_Type *spi_regs = SPI_REGS(dev);
struct spis_nrf5_data *priv_data = DEV_DATA(dev);
__ASSERT(!((tx_buf_len && !tx_buf) || (rx_buf_len && !rx_buf)),
"spis_nrf5_transceive: ERROR - NULL buffers");
/* Buffer needs to be in RAM for EasyDMA to work */
if (!tx_buf || !is_buf_in_ram(tx_buf)) {
SYS_LOG_ERR("Invalid TX buf %p", tx_buf);
return -EINVAL;
}
if (!rx_buf || !is_buf_in_ram(rx_buf)) {
SYS_LOG_ERR("Invalid RX buf %p", rx_buf);
return -EINVAL;
}
priv_data->error = 0;
if (spi_regs->SEMSTAT == 1) {
#if defined(CONFIG_SOC_SERIES_NRF51X)
spi_regs->TXDPTR = (u32_t) tx_buf;
spi_regs->RXDPTR = (u32_t) rx_buf;
spi_regs->MAXTX = tx_buf_len;
spi_regs->MAXRX = rx_buf_len;
#elif defined(CONFIG_SOC_SERIES_NRF52X)
spi_regs->TXD.PTR = (u32_t) tx_buf;
spi_regs->RXD.PTR = (u32_t) rx_buf;
spi_regs->TXD.MAXCNT = tx_buf_len;
spi_regs->RXD.MAXCNT = rx_buf_len;
#endif
spi_regs->TASKS_RELEASE = 1;
} else {
SYS_LOG_ERR("Can't get SEM; unfinished transfer?");
return -EIO;
}
/* wait for transfer to complete */
k_sem_take(&priv_data->device_sync_sem, K_FOREVER);
if (priv_data->error) {
priv_data->error = 0;
return -EIO;
}
return 0;
}
/**
* @brief Complete SPI module data transfer operations.
* @param dev Pointer to the device structure for the driver instance
* @param error Error condition (0 = no error, otherwise an error occurred)
* @return None.
*/
static void spis_nrf5_complete(struct device *dev, u32_t error)
{
__unused NRF_SPIS_Type *spi_regs = SPI_REGS(dev);
__unused u32_t txd_amount, rxd_amount;
struct spis_nrf5_data *priv_data = DEV_DATA(dev);
#if defined(CONFIG_SOC_SERIES_NRF51X)
txd_amount = spi_regs->AMOUNTTX;
rxd_amount = spi_regs->AMOUNTRX;
#elif defined(CONFIG_SOC_SERIES_NRF52X)
txd_amount = spi_regs->RXD.AMOUNT;
rxd_amount = spi_regs->TXD.AMOUNT;
#endif
SYS_LOG_DBG("bytes transferred: TX: %u, RX: %u [err %u (%s)]",
txd_amount, rxd_amount,
error, error == 0 ? "OK" : "ERR");
priv_data->error = error ? 1 : 0;
k_sem_give(&priv_data->device_sync_sem);
}
/**
* @brief SPI module interrupt handler.
* @param arg Pointer to the device structure for the driver instance
* @return None.
*/
static void spis_nrf5_isr(void *arg)
{
struct device *dev = arg;
NRF_SPIS_Type *spi_regs = SPI_REGS(dev);
u32_t error;
u32_t tmp;
/* We get an interrupt for the following reasons:
* 1. Semaphore ACQUIRED:
* Semaphore is assigned to the CPU again (always happens
* after END if the END_ACQUIRE SHORTS is set)
* 2. End of Granted SPI transaction:
* Used to unblocked the caller, finishing the transaction
*/
/* NOTE:
* Section 15.8.1 of nrf52 manual suggests reading back the register
* to cause a 4-cycle delay to prevent the interrupt from
* re-occurring
*/
if (spi_regs->EVENTS_END) {
spi_regs->EVENTS_END = 0;
/* force register flush (per spec) */
tmp = spi_regs->EVENTS_END;
/* Read and clear error flags. */
error = spi_regs->STATUS;
spi_regs->STATUS = error;
spis_nrf5_complete(dev, error);
}
if (spi_regs->EVENTS_ACQUIRED) {
spi_regs->EVENTS_ACQUIRED = 0;
/* force registesr flush (per spec) */
tmp = spi_regs->EVENTS_ACQUIRED;
}
}
static const struct spi_driver_api nrf5_spis_api = {
.transceive = spis_nrf5_transceive,
.configure = spis_nrf5_configure,
.slave_select = NULL,
};
#if defined(CONFIG_SOC_SERIES_NRF51X)
static void spis_configure_psel(NRF_SPIS_Type *spi_regs,
const struct spis_nrf5_config *cfg)
{
spi_regs->PSELMOSI = cfg->mosi_pin;
spi_regs->PSELMISO = cfg->miso_pin;
spi_regs->PSELSCK = cfg->sck_pin;
if (cfg->csn_pin == NRF5_SPIS_CSN_DISABLED_CFG) {
spi_regs->PSELCSN = NRF5_SPIS_CSN_DISABLED;
} else {
spi_regs->PSELCSN = cfg->csn_pin;
}
}
#elif defined(CONFIG_SOC_SERIES_NRF52X)
static void spis_configure_psel(NRF_SPIS_Type *spi_regs,
const struct spis_nrf5_config *cfg)
{
spi_regs->PSEL.MOSI = cfg->mosi_pin;
spi_regs->PSEL.MISO = cfg->miso_pin;
spi_regs->PSEL.SCK = cfg->sck_pin;
if (cfg->csn_pin == NRF5_SPIS_CSN_DISABLED_CFG) {
spi_regs->PSEL.CSN = NRF5_SPIS_CSN_DISABLED;
} else {
spi_regs->PSEL.CSN = cfg->csn_pin;
}
}
#else
#error "Unsupported NRF5 SoC"
#endif
static int spis_nrf5_init(struct device *dev)
{
NRF_SPIS_Type *spi_regs = SPI_REGS(dev);
struct spis_nrf5_data *priv_data = DEV_DATA(dev);
const struct spis_nrf5_config *cfg = DEV_CFG(dev);
struct device *gpio_dev;
int ret;
SYS_LOG_DBG("SPI Slave driver init: %p", dev);
/* Enable constant latency for faster SPIS response */
NRF_POWER->TASKS_CONSTLAT = 1;
spi_regs->ENABLE = 0;
gpio_dev = device_get_binding(CONFIG_GPIO_NRF5_P0_DEV_NAME);
ret = gpio_pin_configure(gpio_dev, cfg->miso_pin,
GPIO_DIR_IN | GPIO_PUD_NORMAL);
__ASSERT_NO_MSG(!ret);
ret = gpio_pin_configure(gpio_dev, cfg->mosi_pin,
GPIO_DIR_IN | GPIO_PUD_NORMAL);
__ASSERT_NO_MSG(!ret);
ret = gpio_pin_configure(gpio_dev, cfg->sck_pin,
GPIO_DIR_IN | GPIO_PUD_NORMAL);
__ASSERT_NO_MSG(!ret);
if (cfg->csn_pin != 0xff) {
ret = gpio_pin_configure(gpio_dev, cfg->csn_pin,
GPIO_DIR_IN | GPIO_PUD_PULL_UP);
__ASSERT_NO_MSG(!ret);
}
spis_configure_psel(spi_regs, cfg);
cfg->config_func();
k_sem_init(&priv_data->device_sync_sem, 0, 1);
SYS_LOG_DBG("SPI Slave driver initialized on device: %p", dev);
return 0;
}
/* system bindings */
#ifdef CONFIG_SPIS0_NRF52
static void spis_config_irq_0(void);
static struct spis_nrf5_data spis_nrf5_data_0;
static const struct spis_nrf5_config spis_nrf5_config_0 = {
.regs = NRF_SPIS0,
.config_func = spis_config_irq_0,
.sck_pin = CONFIG_SPIS0_NRF52_GPIO_SCK_PIN,
.mosi_pin = CONFIG_SPIS0_NRF52_GPIO_MOSI_PIN,
.miso_pin = CONFIG_SPIS0_NRF52_GPIO_MISO_PIN,
.csn_pin = CONFIG_SPIS0_NRF52_GPIO_CSN_PIN,
.def = CONFIG_SPIS0_NRF52_DEF,
};
DEVICE_AND_API_INIT(spis_nrf5_port_0, CONFIG_SPI_0_NAME, spis_nrf5_init,
&spis_nrf5_data_0, &spis_nrf5_config_0, PRE_KERNEL_1,
CONFIG_SPI_INIT_PRIORITY, &nrf5_spis_api);
static void spis_config_irq_0(void)
{
IRQ_CONNECT(NRF5_IRQ_SPI0_TWI0_IRQn, CONFIG_SPI_0_IRQ_PRI,
spis_nrf5_isr, DEVICE_GET(spis_nrf5_port_0), 0);
irq_enable(NRF5_IRQ_SPI0_TWI0_IRQn);
}
#endif /* CONFIG_SPIS0_NRF52 */
#ifdef CONFIG_SPIS1_NRF5
static void spis_config_irq_1(void);
static struct spis_nrf5_data spis_nrf5_data_1;
static const struct spis_nrf5_config spis_nrf5_config_1 = {
.regs = NRF_SPIS1,
.config_func = spis_config_irq_1,
.sck_pin = CONFIG_SPIS1_NRF5_GPIO_SCK_PIN,
.mosi_pin = CONFIG_SPIS1_NRF5_GPIO_MOSI_PIN,
.miso_pin = CONFIG_SPIS1_NRF5_GPIO_MISO_PIN,
.csn_pin = CONFIG_SPIS1_NRF5_GPIO_CSN_PIN,
.def = CONFIG_SPIS1_NRF5_DEF,
};
DEVICE_AND_API_INIT(spis_nrf5_port_1, CONFIG_SPI_1_NAME, spis_nrf5_init,
&spis_nrf5_data_1, &spis_nrf5_config_1, PRE_KERNEL_1,
CONFIG_SPI_INIT_PRIORITY, &nrf5_spis_api);
static void spis_config_irq_1(void)
{
IRQ_CONNECT(NRF5_IRQ_SPI1_TWI1_IRQn, CONFIG_SPI_1_IRQ_PRI,
spis_nrf5_isr, DEVICE_GET(spis_nrf5_port_1), 0);
irq_enable(NRF5_IRQ_SPI1_TWI1_IRQn);
}
#endif /* CONFIG_SPIS1_NRF5 */