zephyr/drivers/spi/spi_dw_legacy.c

514 lines
12 KiB
C

/* spi_dw.c - Designware SPI driver implementation */
/*
* Copyright (c) 2015 Intel Corporation.
*
* SPDX-License-Identifier: Apache-2.0
*/
#include <errno.h>
#include <kernel.h>
#include <arch/cpu.h>
#include <misc/__assert.h>
#include <board.h>
#include <device.h>
#include <init.h>
#include <sys_io.h>
#include <clock_control.h>
#include <misc/util.h>
#include <spi.h>
#include <spi_dw.h>
#ifdef CONFIG_IOAPIC
#include <drivers/ioapic.h>
#endif
#define SYS_LOG_DOMAIN "SPI DW"
#define SYS_LOG_LEVEL CONFIG_SYS_LOG_SPI_LEVEL
#include <logging/sys_log.h>
#if (CONFIG_SYS_LOG_SPI_LEVEL == 4)
#define DBG_COUNTER_INIT() \
u32_t __cnt = 0
#define DBG_COUNTER_INC() \
(__cnt++)
#define DBG_COUNTER_RESULT() \
(__cnt)
#else
#define DBG_COUNTER_INIT() {; }
#define DBG_COUNTER_INC() {; }
#define DBG_COUNTER_RESULT() 0
#endif
static void completed(struct device *dev, int error)
{
const struct spi_dw_config *info = dev->config->config_info;
struct spi_dw_data *spi = dev->driver_data;
if (error) {
goto out;
}
/*
* There are several situations here.
* 1. spi_write w rx_buf - need last_tx && rx_buf_len zero to be done.
* 2. spi_write w/o rx_buf - only need to determine when write is done.
* 3. spi_read - need rx_buf_len zero.
*/
if (spi->tx_buf && spi->rx_buf) {
if (!spi->last_tx || spi->rx_buf_len) {
return;
}
} else if (spi->tx_buf) {
if (!spi->last_tx) {
return;
}
} else { /* or, spi->rx_buf!=0 */
if (spi->rx_buf_len) {
return;
}
}
out:
/* need to give time for FIFOs to drain before issuing more commands */
while (test_bit_sr_busy(info->regs)) {
}
spi->error = error;
/* Disabling interrupts */
write_imr(DW_SPI_IMR_MASK, info->regs);
/* Disabling the controller */
clear_bit_ssienr(info->regs);
_spi_control_cs(dev, 0);
SYS_LOG_DBG("SPI transaction completed %s error",
error ? "with" : "without");
k_sem_give(&spi->device_sync_sem);
}
static void push_data(struct device *dev)
{
const struct spi_dw_config *info = dev->config->config_info;
struct spi_dw_data *spi = dev->driver_data;
u32_t data = 0;
u32_t f_tx;
DBG_COUNTER_INIT();
if (spi->rx_buf) {
f_tx = DW_SPI_FIFO_DEPTH - read_txflr(info->regs) -
read_rxflr(info->regs);
if ((int)f_tx < 0) {
f_tx = 0; /* if rx-fifo is full, hold off tx */
}
} else {
f_tx = DW_SPI_FIFO_DEPTH - read_txflr(info->regs);
}
if (f_tx && (spi->tx_buf_len == 0)) {
/* room in fifo, yet nothing to send */
spi->last_tx = 1; /* setting last_tx indicates TX is done */
}
while (f_tx) {
if (spi->tx_buf && spi->tx_buf_len > 0) {
switch (spi->dfs) {
case 1:
data = UNALIGNED_GET((u8_t *)(spi->tx_buf));
break;
case 2:
data = UNALIGNED_GET((u16_t *)(spi->tx_buf));
break;
#ifndef CONFIG_ARC
case 4:
data = UNALIGNED_GET((u32_t *)(spi->tx_buf));
break;
#endif
}
spi->tx_buf += spi->dfs;
spi->tx_buf_len--;
} else if (spi->rx_buf && spi->rx_buf_len > 0) {
/* No need to push more than necessary */
if (spi->rx_buf_len - spi->fifo_diff <= 0) {
break;
}
data = 0;
} else {
/* Nothing to push anymore */
break;
}
write_dr(data, info->regs);
f_tx--;
spi->fifo_diff++;
DBG_COUNTER_INC();
}
if (spi->last_tx) {
write_txftlr(0, info->regs);
/* prevents any further interrupts demanding TX fifo fill */
}
SYS_LOG_DBG("Pushed: %d", DBG_COUNTER_RESULT());
}
static void pull_data(struct device *dev)
{
const struct spi_dw_config *info = dev->config->config_info;
struct spi_dw_data *spi = dev->driver_data;
u32_t data = 0;
DBG_COUNTER_INIT();
while (read_rxflr(info->regs)) {
data = read_dr(info->regs);
DBG_COUNTER_INC();
if (spi->rx_buf && spi->rx_buf_len > 0) {
switch (spi->dfs) {
case 1:
UNALIGNED_PUT(data, (u8_t *)spi->rx_buf);
break;
case 2:
UNALIGNED_PUT(data, (u16_t *)spi->rx_buf);
break;
#ifndef CONFIG_ARC
case 4:
UNALIGNED_PUT(data, (u32_t *)spi->rx_buf);
break;
#endif
}
spi->rx_buf += spi->dfs;
spi->rx_buf_len--;
}
spi->fifo_diff--;
}
if (!spi->rx_buf_len && spi->tx_buf_len < DW_SPI_FIFO_DEPTH) {
write_rxftlr(spi->tx_buf_len - 1, info->regs);
} else if (read_rxftlr(info->regs) >= spi->rx_buf_len) {
write_rxftlr(spi->rx_buf_len - 1, info->regs);
}
SYS_LOG_DBG("Pulled: %d", DBG_COUNTER_RESULT());
}
static inline bool _spi_dw_is_controller_ready(struct device *dev)
{
const struct spi_dw_config *info = dev->config->config_info;
if (test_bit_ssienr(info->regs) || test_bit_sr_busy(info->regs)) {
return false;
}
return true;
}
static int spi_dw_configure(struct device *dev,
struct spi_config *config)
{
const struct spi_dw_config *info = dev->config->config_info;
struct spi_dw_data *spi = dev->driver_data;
u32_t flags = config->config;
u32_t ctrlr0 = 0;
u32_t mode;
SYS_LOG_DBG("%p (0x%x), %p", dev, info->regs, config);
/* Check status */
if (!_spi_dw_is_controller_ready(dev)) {
SYS_LOG_DBG("Controller is busy");
return -EBUSY;
}
/* Word size */
ctrlr0 |= DW_SPI_CTRLR0_DFS(SPI_WORD_SIZE_GET(flags));
/* Determine how many bytes are required per-frame */
spi->dfs = SPI_WS_TO_DFS(SPI_WORD_SIZE_GET(flags));
/* SPI mode */
mode = SPI_MODE(flags);
if (mode & SPI_MODE_CPOL) {
ctrlr0 |= DW_SPI_CTRLR0_SCPOL;
}
if (mode & SPI_MODE_CPHA) {
ctrlr0 |= DW_SPI_CTRLR0_SCPH;
}
if (mode & SPI_MODE_LOOP) {
ctrlr0 |= DW_SPI_CTRLR0_SRL;
}
/* Installing the configuration */
write_ctrlr0(ctrlr0, info->regs);
/*
* Configure the rate. Use this small hack to allow the user to call
* spi_configure() with both a divider (as the driver was initially
* written) and a frequency (as the SPI API suggests to). The clock
* divider is a 16bit value, hence we can fairly, and safely, assume
* that everything above this value is a frequency. The trade-off is
* that if one wants to use a bus frequency of 64kHz (or less), it has
* the use a divider...
*/
if (config->max_sys_freq > 0xffff) {
write_baudr(SPI_DW_CLK_DIVIDER(config->max_sys_freq),
info->regs);
} else {
write_baudr(config->max_sys_freq, info->regs);
}
return 0;
}
static int spi_dw_slave_select(struct device *dev, u32_t slave)
{
struct spi_dw_data *spi = dev->driver_data;
SYS_LOG_DBG("%p %d", dev, slave);
if (slave == 0 || slave > 16) {
return -EINVAL;
}
spi->slave = 1 << (slave - 1);
return 0;
}
static int spi_dw_transceive(struct device *dev,
const void *tx_buf, u32_t tx_buf_len,
void *rx_buf, u32_t rx_buf_len)
{
const struct spi_dw_config *info = dev->config->config_info;
struct spi_dw_data *spi = dev->driver_data;
u32_t rx_thsld = DW_SPI_RXFTLR_DFLT;
u32_t imask;
SYS_LOG_DBG("%p, %p, %u, %p, %u",
dev, tx_buf, tx_buf_len, rx_buf, rx_buf_len);
/* Check status */
if (!_spi_dw_is_controller_ready(dev)) {
SYS_LOG_DBG("Controller is busy");
return -EBUSY;
}
/* Set buffers info */
spi->tx_buf = tx_buf;
spi->tx_buf_len = tx_buf_len/spi->dfs;
spi->rx_buf = rx_buf;
if (rx_buf) {
spi->rx_buf_len = rx_buf_len/spi->dfs;
} else {
spi->rx_buf_len = 0; /* must be zero if no buffer */
}
spi->fifo_diff = 0;
spi->last_tx = 0;
/* Tx Threshold */
write_txftlr(DW_SPI_TXFTLR_DFLT, info->regs);
/* Does Rx thresholds needs to be lower? */
if (spi->rx_buf_len && spi->rx_buf_len < DW_SPI_FIFO_DEPTH) {
rx_thsld = spi->rx_buf_len - 1;
} else if (!spi->rx_buf_len && spi->tx_buf_len < DW_SPI_FIFO_DEPTH) {
rx_thsld = spi->tx_buf_len - 1;
/* TODO: why? */
}
write_rxftlr(rx_thsld, info->regs);
/* Slave select */
write_ser(spi->slave, info->regs);
_spi_control_cs(dev, 1);
/* Enable interrupts */
imask = DW_SPI_IMR_UNMASK;
if (!rx_buf) {
/* if there is no rx buffer, keep all rx interrupts masked */
imask &= DW_SPI_IMR_MASK_RX;
}
write_imr(imask, info->regs);
/* Enable the controller */
set_bit_ssienr(info->regs);
k_sem_take(&spi->device_sync_sem, K_FOREVER);
if (spi->error) {
spi->error = 0;
return -EIO;
}
return 0;
}
void spi_dw_isr(void *arg)
{
struct device *dev = (struct device *)arg;
const struct spi_dw_config *info = dev->config->config_info;
u32_t error = 0;
u32_t int_status;
int_status = read_isr(info->regs);
SYS_LOG_DBG("SPI int_status 0x%x - (tx: %d, rx: %d)",
int_status, read_txflr(info->regs), read_rxflr(info->regs));
if (int_status & DW_SPI_ISR_ERRORS_MASK) {
error = 1;
goto out;
}
if (int_status & DW_SPI_ISR_RXFIS) {
pull_data(dev);
}
if (int_status & DW_SPI_ISR_TXEIS) {
push_data(dev);
}
out:
clear_interrupts(info->regs);
completed(dev, error);
}
static const struct spi_driver_api dw_spi_api = {
.configure = spi_dw_configure,
.slave_select = spi_dw_slave_select,
.transceive = spi_dw_transceive,
};
int spi_dw_init(struct device *dev)
{
const struct spi_dw_config *info = dev->config->config_info;
struct spi_dw_data *spi = dev->driver_data;
_clock_config(dev);
_clock_on(dev);
info->config_func();
k_sem_init(&spi->device_sync_sem, 0, UINT_MAX);
_spi_config_cs(dev);
/* Masking interrupt and making sure controller is disabled */
write_imr(DW_SPI_IMR_MASK, info->regs);
clear_bit_ssienr(info->regs);
SYS_LOG_DBG("Designware SPI driver initialized on device: %p", dev);
return 0;
}
#ifdef CONFIG_SPI_0
void spi_config_0_irq(void);
struct spi_dw_data spi_dw_data_port_0;
const struct spi_dw_config spi_dw_config_0 = {
.regs = SPI_DW_PORT_0_REGS,
#ifdef CONFIG_SPI_DW_CLOCK_GATE
.clock_data = UINT_TO_POINTER(CONFIG_SPI_0_CLOCK_GATE_SUBSYS),
#endif /* CONFIG_SPI_DW_CLOCK_GATE */
#ifdef CONFIG_SPI_DW_CS_GPIO
.cs_gpio_name = CONFIG_SPI_0_CS_GPIO_PORT,
.cs_gpio_pin = CONFIG_SPI_0_CS_GPIO_PIN,
#endif
.config_func = spi_config_0_irq
};
DEVICE_AND_API_INIT(spi_dw_port_0, CONFIG_SPI_0_NAME, spi_dw_init,
&spi_dw_data_port_0, &spi_dw_config_0,
POST_KERNEL, CONFIG_SPI_INIT_PRIORITY,
&dw_spi_api);
void spi_config_0_irq(void)
{
#ifdef CONFIG_SPI_DW_INTERRUPT_SINGLE_LINE
IRQ_CONNECT(SPI_DW_PORT_0_IRQ, CONFIG_SPI_0_IRQ_PRI,
spi_dw_isr, DEVICE_GET(spi_dw_port_0), SPI_DW_IRQ_FLAGS);
irq_enable(SPI_DW_PORT_0_IRQ);
_spi_int_unmask(SPI_DW_PORT_0_INT_MASK);
#else /* SPI_DW_INTERRUPT_SEPARATED_LINES */
IRQ_CONNECT(IRQ_SPI0_RX_AVAIL, CONFIG_SPI_0_IRQ_PRI,
spi_dw_isr, DEVICE_GET(spi_dw_port_0), SPI_DW_IRQ_FLAGS);
IRQ_CONNECT(IRQ_SPI0_TX_REQ, CONFIG_SPI_0_IRQ_PRI,
spi_dw_isr, DEVICE_GET(spi_dw_port_0), SPI_DW_IRQ_FLAGS);
IRQ_CONNECT(IRQ_SPI0_ERR_INT, CONFIG_SPI_0_IRQ_PRI,
spi_dw_isr, DEVICE_GET(spi_dw_port_0), SPI_DW_IRQ_FLAGS);
irq_enable(IRQ_SPI0_RX_AVAIL);
irq_enable(IRQ_SPI0_TX_REQ);
irq_enable(IRQ_SPI0_ERR_INT);
_spi_int_unmask(SPI_DW_PORT_0_RX_INT_MASK);
_spi_int_unmask(SPI_DW_PORT_0_TX_INT_MASK);
_spi_int_unmask(SPI_DW_PORT_0_ERROR_INT_MASK);
#endif
}
#endif /* CONFIG_SPI_0 */
#ifdef CONFIG_SPI_1
void spi_config_1_irq(void);
struct spi_dw_data spi_dw_data_port_1;
static const struct spi_dw_config spi_dw_config_1 = {
.regs = SPI_DW_PORT_1_REGS,
#ifdef CONFIG_SPI_DW_CLOCK_GATE
.clock_data = UINT_TO_POINTER(CONFIG_SPI_1_CLOCK_GATE_SUBSYS),
#endif /* CONFIG_SPI_DW_CLOCK_GATE */
#ifdef CONFIG_SPI_DW_CS_GPIO
.cs_gpio_name = CONFIG_SPI_1_CS_GPIO_PORT,
.cs_gpio_pin = CONFIG_SPI_1_CS_GPIO_PIN,
#endif
.config_func = spi_config_1_irq
};
DEVICE_AND_API_INIT(spi_dw_port_1, CONFIG_SPI_1_NAME, spi_dw_init,
&spi_dw_data_port_1, &spi_dw_config_1,
POST_KERNEL, CONFIG_SPI_INIT_PRIORITY,
&dw_spi_api);
void spi_config_1_irq(void)
{
#ifdef CONFIG_SPI_DW_INTERRUPT_SINGLE_LINE
IRQ_CONNECT(SPI_DW_PORT_1_IRQ, CONFIG_SPI_1_IRQ_PRI,
spi_dw_isr, DEVICE_GET(spi_dw_port_1), SPI_DW_IRQ_FLAGS);
irq_enable(SPI_DW_PORT_1_IRQ);
_spi_int_unmask(SPI_DW_PORT_1_INT_MASK);
#else /* SPI_DW_INTERRUPT_SEPARATED_LINES */
IRQ_CONNECT(IRQ_SPI1_RX_AVAIL, CONFIG_SPI_1_IRQ_PRI,
spi_dw_isr, DEVICE_GET(spi_dw_port_1), SPI_DW_IRQ_FLAGS);
IRQ_CONNECT(IRQ_SPI1_TX_REQ, CONFIG_SPI_1_IRQ_PRI,
spi_dw_isr, DEVICE_GET(spi_dw_port_1), SPI_DW_IRQ_FLAGS);
IRQ_CONNECT(IRQ_SPI1_ERR_INT, CONFIG_SPI_1_IRQ_PRI,
spi_dw_isr, DEVICE_GET(spi_dw_port_1), SPI_DW_IRQ_FLAGS);
irq_enable(IRQ_SPI1_RX_AVAIL);
irq_enable(IRQ_SPI1_TX_REQ);
irq_enable(IRQ_SPI1_ERR_INT);
_spi_int_unmask(SPI_DW_PORT_1_RX_INT_MASK);
_spi_int_unmask(SPI_DW_PORT_1_TX_INT_MASK);
_spi_int_unmask(SPI_DW_PORT_1_ERROR_INT_MASK);
#endif
}
#endif /* CONFIG_SPI_1 */