sirfsoc_uart.c
/*
* Driver for CSR SiRFprimaII onboard UARTs.
*
* Copyright (c) 2011 Cambridge Silicon Radio Limited, a CSR plc group company.
*
* Licensed under GPLv2 or later.
*/
#include <linux/module.h>
#include <linux/ioport.h>
#include <linux/platform_device.h>
#include <linux/init.h>
#include <linux/sysrq.h>
#include <linux/console.h>
#include <linux/tty.h>
#include <linux/tty_flip.h>
#include <linux/serial_core.h>
#include <linux/serial.h>
#include <linux/clk.h>
#include <linux/of.h>
#include <linux/slab.h>
#include <linux/io.h>
#include <linux/of_gpio.h>
#include <linux/dmaengine.h>
#include <linux/dma-direction.h>
#include <linux/dma-mapping.h>
#include <asm/irq.h>
#include <asm/mach/irq.h>
#include "sirfsoc_uart.h"
static unsigned int
sirfsoc_uart_pio_tx_chars(struct sirfsoc_uart_port *sirfport, int count);
static unsigned int
sirfsoc_uart_pio_rx_chars(struct uart_port *port, unsigned int max_rx_count);
static struct uart_driver sirfsoc_uart_drv;
static void sirfsoc_uart_tx_dma_complete_callback(void *param);
static const struct sirfsoc_baudrate_to_regv baudrate_to_regv[] = {
{4000000, 2359296},
{3500000, 1310721},
{3000000, 1572865},
{2500000, 1245186},
{2000000, 1572866},
{1500000, 1245188},
{1152000, 1638404},
{1000000, 1572869},
{921600, 1114120},
{576000, 1245196},
{500000, 1245198},
{460800, 1572876},
{230400, 1310750},
{115200, 1310781},
{57600, 1310843},
{38400, 1114328},
{19200, 1114545},
{9600, 1114979},
};
static struct sirfsoc_uart_port *sirf_ports[SIRFSOC_UART_NR];
static inline struct sirfsoc_uart_port *to_sirfport(struct uart_port *port)
{
return container_of(port, struct sirfsoc_uart_port, port);
}
static inline unsigned int sirfsoc_uart_tx_empty(struct uart_port *port)
{
unsigned long reg;
struct sirfsoc_uart_port *sirfport = to_sirfport(port);
struct sirfsoc_register *ureg = &sirfport->uart_reg->uart_reg;
struct sirfsoc_fifo_status *ufifo_st = &sirfport->uart_reg->fifo_status;
reg = rd_regl(port, ureg->sirfsoc_tx_fifo_status);
return (reg & ufifo_st->ff_empty(port)) ? TIOCSER_TEMT : 0;
}
static unsigned int sirfsoc_uart_get_mctrl(struct uart_port *port)
{
struct sirfsoc_uart_port *sirfport = to_sirfport(port);
struct sirfsoc_register *ureg = &sirfport->uart_reg->uart_reg;
if (!sirfport->hw_flow_ctrl || !sirfport->ms_enabled)
goto cts_asserted;
if (sirfport->uart_reg->uart_type == SIRF_REAL_UART) {
if (!(rd_regl(port, ureg->sirfsoc_afc_ctrl) &
SIRFUART_AFC_CTS_STATUS))
goto cts_asserted;
else
goto cts_deasserted;
} else {
if (!gpio_get_value(sirfport->cts_gpio))
goto cts_asserted;
else
goto cts_deasserted;
}
cts_deasserted:
return TIOCM_CAR | TIOCM_DSR;
cts_asserted:
return TIOCM_CAR | TIOCM_DSR | TIOCM_CTS;
}
static void sirfsoc_uart_set_mctrl(struct uart_port *port, unsigned int mctrl)
{
struct sirfsoc_uart_port *sirfport = to_sirfport(port);
struct sirfsoc_register *ureg = &sirfport->uart_reg->uart_reg;
unsigned int assert = mctrl & TIOCM_RTS;
unsigned int val = assert ? SIRFUART_AFC_CTRL_RX_THD : 0x0;
unsigned int current_val;
if (mctrl & TIOCM_LOOP) {
if (sirfport->uart_reg->uart_type == SIRF_REAL_UART)
wr_regl(port, ureg->sirfsoc_line_ctrl,
rd_regl(port, ureg->sirfsoc_line_ctrl) |
SIRFUART_LOOP_BACK);
else
wr_regl(port, ureg->sirfsoc_mode1,
rd_regl(port, ureg->sirfsoc_mode1) |
SIRFSOC_USP_LOOP_BACK_CTRL);
} else {
if (sirfport->uart_reg->uart_type == SIRF_REAL_UART)
wr_regl(port, ureg->sirfsoc_line_ctrl,
rd_regl(port, ureg->sirfsoc_line_ctrl) &
~SIRFUART_LOOP_BACK);
else
wr_regl(port, ureg->sirfsoc_mode1,
rd_regl(port, ureg->sirfsoc_mode1) &
~SIRFSOC_USP_LOOP_BACK_CTRL);
}
if (!sirfport->hw_flow_ctrl || !sirfport->ms_enabled)
return;
if (sirfport->uart_reg->uart_type == SIRF_REAL_UART) {
current_val = rd_regl(port, ureg->sirfsoc_afc_ctrl) & ~0xFF;
val |= current_val;
wr_regl(port, ureg->sirfsoc_afc_ctrl, val);
} else {
if (!val)
gpio_set_value(sirfport->rts_gpio, 1);
else
gpio_set_value(sirfport->rts_gpio, 0);
}
}
static void sirfsoc_uart_stop_tx(struct uart_port *port)
{
struct sirfsoc_uart_port *sirfport = to_sirfport(port);
struct sirfsoc_register *ureg = &sirfport->uart_reg->uart_reg;
struct sirfsoc_int_en *uint_en = &sirfport->uart_reg->uart_int_en;
if (sirfport->tx_dma_chan) {
if (sirfport->tx_dma_state == TX_DMA_RUNNING) {
dmaengine_pause(sirfport->tx_dma_chan);
sirfport->tx_dma_state = TX_DMA_PAUSE;
} else {
if (!sirfport->is_atlas7)
wr_regl(port, ureg->sirfsoc_int_en_reg,
rd_regl(port, ureg->sirfsoc_int_en_reg) &
~uint_en->sirfsoc_txfifo_empty_en);
else
wr_regl(port, ureg->sirfsoc_int_en_clr_reg,
uint_en->sirfsoc_txfifo_empty_en);
}
} else {
if (sirfport->uart_reg->uart_type == SIRF_USP_UART)
wr_regl(port, ureg->sirfsoc_tx_rx_en, rd_regl(port,
ureg->sirfsoc_tx_rx_en) & ~SIRFUART_TX_EN);
if (!sirfport->is_atlas7)
wr_regl(port, ureg->sirfsoc_int_en_reg,
rd_regl(port, ureg->sirfsoc_int_en_reg) &
~uint_en->sirfsoc_txfifo_empty_en);
else
wr_regl(port, ureg->sirfsoc_int_en_clr_reg,
uint_en->sirfsoc_txfifo_empty_en);
}
}
static void sirfsoc_uart_tx_with_dma(struct sirfsoc_uart_port *sirfport)
{
struct uart_port *port = &sirfport->port;
struct sirfsoc_register *ureg = &sirfport->uart_reg->uart_reg;
struct sirfsoc_int_en *uint_en = &sirfport->uart_reg->uart_int_en;
struct circ_buf *xmit = &port->state->xmit;
unsigned long tran_size;
unsigned long tran_start;
unsigned long pio_tx_size;
tran_size = CIRC_CNT_TO_END(xmit->head, xmit->tail, UART_XMIT_SIZE);
tran_start = (unsigned long)(xmit->buf + xmit->tail);
if (uart_circ_empty(xmit) || uart_tx_stopped(port) ||
!tran_size)
return;
if (sirfport->tx_dma_state == TX_DMA_PAUSE) {
dmaengine_resume(sirfport->tx_dma_chan);
return;
}
if (sirfport->tx_dma_state == TX_DMA_RUNNING)
return;
if (!sirfport->is_atlas7)
wr_regl(port, ureg->sirfsoc_int_en_reg,
rd_regl(port, ureg->sirfsoc_int_en_reg)&
~(uint_en->sirfsoc_txfifo_empty_en));
else
wr_regl(port, ureg->sirfsoc_int_en_clr_reg,
uint_en->sirfsoc_txfifo_empty_en);
/*
* DMA requires buffer address and buffer length are both aligned with
* 4 bytes, so we use PIO for
* 1. if address is not aligned with 4bytes, use PIO for the first 1~3
* bytes, and move to DMA for the left part aligned with 4bytes
* 2. if buffer length is not aligned with 4bytes, use DMA for aligned
* part first, move to PIO for the left 1~3 bytes
*/
if (tran_size < 4 || BYTES_TO_ALIGN(tran_start)) {
wr_regl(port, ureg->sirfsoc_tx_fifo_op, SIRFUART_FIFO_STOP);
wr_regl(port, ureg->sirfsoc_tx_dma_io_ctrl,
rd_regl(port, ureg->sirfsoc_tx_dma_io_ctrl)|
SIRFUART_IO_MODE);
if (BYTES_TO_ALIGN(tran_start)) {
pio_tx_size = sirfsoc_uart_pio_tx_chars(sirfport,
BYTES_TO_ALIGN(tran_start));
tran_size -= pio_tx_size;
}
if (tran_size < 4)
sirfsoc_uart_pio_tx_chars(sirfport, tran_size);
if (!sirfport->is_atlas7)
wr_regl(port, ureg->sirfsoc_int_en_reg,
rd_regl(port, ureg->sirfsoc_int_en_reg)|
uint_en->sirfsoc_txfifo_empty_en);
else
wr_regl(port, ureg->sirfsoc_int_en_reg,
uint_en->sirfsoc_txfifo_empty_en);
wr_regl(port, ureg->sirfsoc_tx_fifo_op, SIRFUART_FIFO_START);
} else {
/* tx transfer mode switch into dma mode */
wr_regl(port, ureg->sirfsoc_tx_fifo_op, SIRFUART_FIFO_STOP);
wr_regl(port, ureg->sirfsoc_tx_dma_io_ctrl,
rd_regl(port, ureg->sirfsoc_tx_dma_io_ctrl)&
~SIRFUART_IO_MODE);
wr_regl(port, ureg->sirfsoc_tx_fifo_op, SIRFUART_FIFO_START);
tran_size &= ~(0x3);
sirfport->tx_dma_addr = dma_map_single(port->dev,
xmit->buf + xmit->tail,
tran_size, DMA_TO_DEVICE);
sirfport->tx_dma_desc = dmaengine_prep_slave_single(
sirfport->tx_dma_chan, sirfport->tx_dma_addr,
tran_size, DMA_MEM_TO_DEV, DMA_PREP_INTERRUPT);
if (!sirfport->tx_dma_desc) {
dev_err(port->dev, "DMA prep slave single fail\n");
return;
}
sirfport->tx_dma_desc->callback =
sirfsoc_uart_tx_dma_complete_callback;
sirfport->tx_dma_desc->callback_param = (void *)sirfport;
sirfport->transfer_size = tran_size;
dmaengine_submit(sirfport->tx_dma_desc);
dma_async_issue_pending(sirfport->tx_dma_chan);
sirfport->tx_dma_state = TX_DMA_RUNNING;
}
}
static void sirfsoc_uart_start_tx(struct uart_port *port)
{
struct sirfsoc_uart_port *sirfport = to_sirfport(port);
struct sirfsoc_register *ureg = &sirfport->uart_reg->uart_reg;
struct sirfsoc_int_en *uint_en = &sirfport->uart_reg->uart_int_en;
if (sirfport->tx_dma_chan)
sirfsoc_uart_tx_with_dma(sirfport);
else {
if (sirfport->uart_reg->uart_type == SIRF_USP_UART)
wr_regl(port, ureg->sirfsoc_tx_rx_en, rd_regl(port,
ureg->sirfsoc_tx_rx_en) | SIRFUART_TX_EN);
wr_regl(port, ureg->sirfsoc_tx_fifo_op, SIRFUART_FIFO_STOP);
sirfsoc_uart_pio_tx_chars(sirfport, port->fifosize);
wr_regl(port, ureg->sirfsoc_tx_fifo_op, SIRFUART_FIFO_START);
if (!sirfport->is_atlas7)
wr_regl(port, ureg->sirfsoc_int_en_reg,
rd_regl(port, ureg->sirfsoc_int_en_reg)|
uint_en->sirfsoc_txfifo_empty_en);
else
wr_regl(port, ureg->sirfsoc_int_en_reg,
uint_en->sirfsoc_txfifo_empty_en);
}
}
static void sirfsoc_uart_stop_rx(struct uart_port *port)
{
struct sirfsoc_uart_port *sirfport = to_sirfport(port);
struct sirfsoc_register *ureg = &sirfport->uart_reg->uart_reg;
struct sirfsoc_int_en *uint_en = &sirfport->uart_reg->uart_int_en;
wr_regl(port, ureg->sirfsoc_rx_fifo_op, 0);
if (sirfport->rx_dma_chan) {
if (!sirfport->is_atlas7)
wr_regl(port, ureg->sirfsoc_int_en_reg,
rd_regl(port, ureg->sirfsoc_int_en_reg) &
~(SIRFUART_RX_DMA_INT_EN(uint_en,
sirfport->uart_reg->uart_type) |
uint_en->sirfsoc_rx_done_en));
else
wr_regl(port, ureg->sirfsoc_int_en_clr_reg,
SIRFUART_RX_DMA_INT_EN(uint_en,
sirfport->uart_reg->uart_type)|
uint_en->sirfsoc_rx_done_en);
dmaengine_terminate_all(sirfport->rx_dma_chan);
} else {
if (!sirfport->is_atlas7)
wr_regl(port, ureg->sirfsoc_int_en_reg,
rd_regl(port, ureg->sirfsoc_int_en_reg)&
~(SIRFUART_RX_IO_INT_EN(uint_en,
sirfport->uart_reg->uart_type)));
else
wr_regl(port, ureg->sirfsoc_int_en_clr_reg,
SIRFUART_RX_IO_INT_EN(uint_en,
sirfport->uart_reg->uart_type));
}
}
static void sirfsoc_uart_disable_ms(struct uart_port *port)
{
struct sirfsoc_uart_port *sirfport = to_sirfport(port);
struct sirfsoc_register *ureg = &sirfport->uart_reg->uart_reg;
struct sirfsoc_int_en *uint_en = &sirfport->uart_reg->uart_int_en;
if (!sirfport->hw_flow_ctrl)
return;
sirfport->ms_enabled = false;
if (sirfport->uart_reg->uart_type == SIRF_REAL_UART) {
wr_regl(port, ureg->sirfsoc_afc_ctrl,
rd_regl(port, ureg->sirfsoc_afc_ctrl) & ~0x3FF);
if (!sirfport->is_atlas7)
wr_regl(port, ureg->sirfsoc_int_en_reg,
rd_regl(port, ureg->sirfsoc_int_en_reg)&
~uint_en->sirfsoc_cts_en);
else
wr_regl(port, ureg->sirfsoc_int_en_clr_reg,
uint_en->sirfsoc_cts_en);
} else
disable_irq(gpio_to_irq(sirfport->cts_gpio));
}
static irqreturn_t sirfsoc_uart_usp_cts_handler(int irq, void *dev_id)
{
struct sirfsoc_uart_port *sirfport = (struct sirfsoc_uart_port *)dev_id;
struct uart_port *port = &sirfport->port;
spin_lock(&port->lock);
if (gpio_is_valid(sirfport->cts_gpio) && sirfport->ms_enabled)
uart_handle_cts_change(port,
!gpio_get_value(sirfport->cts_gpio));
spin_unlock(&port->lock);
return IRQ_HANDLED;
}
static void sirfsoc_uart_enable_ms(struct uart_port *port)
{
struct sirfsoc_uart_port *sirfport = to_sirfport(port);
struct sirfsoc_register *ureg = &sirfport->uart_reg->uart_reg;
struct sirfsoc_int_en *uint_en = &sirfport->uart_reg->uart_int_en;
if (!sirfport->hw_flow_ctrl)
return;
sirfport->ms_enabled = true;
if (sirfport->uart_reg->uart_type == SIRF_REAL_UART) {
wr_regl(port, ureg->sirfsoc_afc_ctrl,
rd_regl(port, ureg->sirfsoc_afc_ctrl) |
SIRFUART_AFC_TX_EN | SIRFUART_AFC_RX_EN |
SIRFUART_AFC_CTRL_RX_THD);
if (!sirfport->is_atlas7)
wr_regl(port, ureg->sirfsoc_int_en_reg,
rd_regl(port, ureg->sirfsoc_int_en_reg)
| uint_en->sirfsoc_cts_en);
else
wr_regl(port, ureg->sirfsoc_int_en_reg,
uint_en->sirfsoc_cts_en);
} else
enable_irq(gpio_to_irq(sirfport->cts_gpio));
}
static void sirfsoc_uart_break_ctl(struct uart_port *port, int break_state)
{
struct sirfsoc_uart_port *sirfport = to_sirfport(port);
struct sirfsoc_register *ureg = &sirfport->uart_reg->uart_reg;
if (sirfport->uart_reg->uart_type == SIRF_REAL_UART) {
unsigned long ulcon = rd_regl(port, ureg->sirfsoc_line_ctrl);
if (break_state)
ulcon |= SIRFUART_SET_BREAK;
else
ulcon &= ~SIRFUART_SET_BREAK;
wr_regl(port, ureg->sirfsoc_line_ctrl, ulcon);
}
}
static unsigned int
sirfsoc_uart_pio_rx_chars(struct uart_port *port, unsigned int max_rx_count)
{
struct sirfsoc_uart_port *sirfport = to_sirfport(port);
struct sirfsoc_register *ureg = &sirfport->uart_reg->uart_reg;
struct sirfsoc_fifo_status *ufifo_st = &sirfport->uart_reg->fifo_status;
unsigned int ch, rx_count = 0;
struct tty_struct *tty;
tty = tty_port_tty_get(&port->state->port);
if (!tty)
return -ENODEV;
while (!(rd_regl(port, ureg->sirfsoc_rx_fifo_status) &
ufifo_st->ff_empty(port))) {
ch = rd_regl(port, ureg->sirfsoc_rx_fifo_data) |
SIRFUART_DUMMY_READ;
if (unlikely(uart_handle_sysrq_char(port, ch)))
continue;
uart_insert_char(port, 0, 0, ch, TTY_NORMAL);
rx_count++;
if (rx_count >= max_rx_count)
break;
}
port->icount.rx += rx_count;
return rx_count;
}
static unsigned int
sirfsoc_uart_pio_tx_chars(struct sirfsoc_uart_port *sirfport, int count)
{
struct uart_port *port = &sirfport->port;
struct sirfsoc_register *ureg = &sirfport->uart_reg->uart_reg;
struct sirfsoc_fifo_status *ufifo_st = &sirfport->uart_reg->fifo_status;
struct circ_buf *xmit = &port->state->xmit;
unsigned int num_tx = 0;
while (!uart_circ_empty(xmit) &&
!(rd_regl(port, ureg->sirfsoc_tx_fifo_status) &
ufifo_st->ff_full(port)) &&
count--) {
wr_regl(port, ureg->sirfsoc_tx_fifo_data,
xmit->buf[xmit->tail]);
xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
port->icount.tx++;
num_tx++;
}
if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
uart_write_wakeup(port);
return num_tx;
}
static void sirfsoc_uart_tx_dma_complete_callback(void *param)
{
struct sirfsoc_uart_port *sirfport = (struct sirfsoc_uart_port *)param;
struct uart_port *port = &sirfport->port;
struct circ_buf *xmit = &port->state->xmit;
unsigned long flags;
spin_lock_irqsave(&port->lock, flags);
xmit->tail = (xmit->tail + sirfport->transfer_size) &
(UART_XMIT_SIZE - 1);
port->icount.tx += sirfport->transfer_size;
if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
uart_write_wakeup(port);
if (sirfport->tx_dma_addr)
dma_unmap_single(port->dev, sirfport->tx_dma_addr,
sirfport->transfer_size, DMA_TO_DEVICE);
sirfport->tx_dma_state = TX_DMA_IDLE;
sirfsoc_uart_tx_with_dma(sirfport);
spin_unlock_irqrestore(&port->lock, flags);
}
static irqreturn_t sirfsoc_uart_isr(int irq, void *dev_id)
{
unsigned long intr_status;
unsigned long cts_status;
unsigned long flag = TTY_NORMAL;
struct sirfsoc_uart_port *sirfport = (struct sirfsoc_uart_port *)dev_id;
struct uart_port *port = &sirfport->port;
struct sirfsoc_register *ureg = &sirfport->uart_reg->uart_reg;
struct sirfsoc_fifo_status *ufifo_st = &sirfport->uart_reg->fifo_status;
struct sirfsoc_int_status *uint_st = &sirfport->uart_reg->uart_int_st;
struct sirfsoc_int_en *uint_en = &sirfport->uart_reg->uart_int_en;
struct uart_state *state = port->state;
struct circ_buf *xmit = &port->state->xmit;
spin_lock(&port->lock);
intr_status = rd_regl(port, ureg->sirfsoc_int_st_reg);
wr_regl(port, ureg->sirfsoc_int_st_reg, intr_status);
intr_status &= rd_regl(port, ureg->sirfsoc_int_en_reg);
if (unlikely(intr_status & (SIRFUART_ERR_INT_STAT(uint_st,
sirfport->uart_reg->uart_type)))) {
if (intr_status & uint_st->sirfsoc_rxd_brk) {
port->icount.brk++;
if (uart_handle_break(port))
goto recv_char;
}
if (intr_status & uint_st->sirfsoc_rx_oflow) {
port->icount.overrun++;
flag = TTY_OVERRUN;
}
if (intr_status & uint_st->sirfsoc_frm_err) {
port->icount.frame++;
flag = TTY_FRAME;
}
if (intr_status & uint_st->sirfsoc_parity_err) {
port->icount.parity++;
flag = TTY_PARITY;
}
wr_regl(port, ureg->sirfsoc_rx_fifo_op, SIRFUART_FIFO_RESET);
wr_regl(port, ureg->sirfsoc_rx_fifo_op, 0);
wr_regl(port, ureg->sirfsoc_rx_fifo_op, SIRFUART_FIFO_START);
intr_status &= port->read_status_mask;
uart_insert_char(port, intr_status,
uint_en->sirfsoc_rx_oflow_en, 0, flag);
}
recv_char:
if ((sirfport->uart_reg->uart_type == SIRF_REAL_UART) &&
(intr_status & SIRFUART_CTS_INT_ST(uint_st)) &&
!sirfport->tx_dma_state) {
cts_status = rd_regl(port, ureg->sirfsoc_afc_ctrl) &
SIRFUART_AFC_CTS_STATUS;
if (cts_status != 0)
cts_status = 0;
else
cts_status = 1;
uart_handle_cts_change(port, cts_status);
wake_up_interruptible(&state->port.delta_msr_wait);
}
if (!sirfport->rx_dma_chan &&
(intr_status & SIRFUART_RX_IO_INT_ST(uint_st))) {
/*
* chip will trigger continuous RX_TIMEOUT interrupt
* in RXFIFO empty and not trigger if RXFIFO recevice
* data in limit time, original method use RX_TIMEOUT
* will trigger lots of useless interrupt in RXFIFO
* empty.RXFIFO received one byte will trigger RX_DONE
* interrupt.use RX_DONE to wait for data received
* into RXFIFO, use RX_THD/RX_FULL for lots data receive
* and use RX_TIMEOUT for the last left data.
*/
if (intr_status & uint_st->sirfsoc_rx_done) {
if (!sirfport->is_atlas7) {
wr_regl(port, ureg->sirfsoc_int_en_reg,
rd_regl(port, ureg->sirfsoc_int_en_reg)
& ~(uint_en->sirfsoc_rx_done_en));
wr_regl(port, ureg->sirfsoc_int_en_reg,
rd_regl(port, ureg->sirfsoc_int_en_reg)
| (uint_en->sirfsoc_rx_timeout_en));
} else {
wr_regl(port, ureg->sirfsoc_int_en_clr_reg,
uint_en->sirfsoc_rx_done_en);
wr_regl(port, ureg->sirfsoc_int_en_reg,
uint_en->sirfsoc_rx_timeout_en);
}
} else {
if (intr_status & uint_st->sirfsoc_rx_timeout) {
if (!sirfport->is_atlas7) {
wr_regl(port, ureg->sirfsoc_int_en_reg,
rd_regl(port, ureg->sirfsoc_int_en_reg)
& ~(uint_en->sirfsoc_rx_timeout_en));
wr_regl(port, ureg->sirfsoc_int_en_reg,
rd_regl(port, ureg->sirfsoc_int_en_reg)
| (uint_en->sirfsoc_rx_done_en));
} else {
wr_regl(port,
ureg->sirfsoc_int_en_clr_reg,
uint_en->sirfsoc_rx_timeout_en);
wr_regl(port, ureg->sirfsoc_int_en_reg,
uint_en->sirfsoc_rx_done_en);
}
}
sirfsoc_uart_pio_rx_chars(port, port->fifosize);
}
}
spin_unlock(&port->lock);
tty_flip_buffer_push(&state->port);
spin_lock(&port->lock);
if (intr_status & uint_st->sirfsoc_txfifo_empty) {
if (sirfport->tx_dma_chan)
sirfsoc_uart_tx_with_dma(sirfport);
else {
if (uart_circ_empty(xmit) || uart_tx_stopped(port)) {
spin_unlock(&port->lock);
return IRQ_HANDLED;
} else {
sirfsoc_uart_pio_tx_chars(sirfport,
port->fifosize);
if ((uart_circ_empty(xmit)) &&
(rd_regl(port, ureg->sirfsoc_tx_fifo_status) &
ufifo_st->ff_empty(port)))
sirfsoc_uart_stop_tx(port);
}
}
}
spin_unlock(&port->lock);
return IRQ_HANDLED;
}
static void sirfsoc_uart_rx_dma_complete_callback(void *param)
{
}
/* submit rx dma task into dmaengine */
static void sirfsoc_uart_start_next_rx_dma(struct uart_port *port)
{
struct sirfsoc_uart_port *sirfport = to_sirfport(port);
struct sirfsoc_register *ureg = &sirfport->uart_reg->uart_reg;
struct sirfsoc_int_en *uint_en = &sirfport->uart_reg->uart_int_en;
wr_regl(port, ureg->sirfsoc_rx_dma_io_ctrl,
rd_regl(port, ureg->sirfsoc_rx_dma_io_ctrl) &
~SIRFUART_IO_MODE);
sirfport->rx_dma_items.xmit.tail =
sirfport->rx_dma_items.xmit.head = 0;
sirfport->rx_dma_items.desc =
dmaengine_prep_dma_cyclic(sirfport->rx_dma_chan,
sirfport->rx_dma_items.dma_addr, SIRFSOC_RX_DMA_BUF_SIZE,
SIRFSOC_RX_DMA_BUF_SIZE / 2,
DMA_DEV_TO_MEM, DMA_PREP_INTERRUPT);
if (IS_ERR_OR_NULL(sirfport->rx_dma_items.desc)) {
dev_err(port->dev, "DMA slave single fail\n");
return;
}
sirfport->rx_dma_items.desc->callback =
sirfsoc_uart_rx_dma_complete_callback;
sirfport->rx_dma_items.desc->callback_param = sirfport;
sirfport->rx_dma_items.cookie =
dmaengine_submit(sirfport->rx_dma_items.desc);
dma_async_issue_pending(sirfport->rx_dma_chan);
if (!sirfport->is_atlas7)
wr_regl(port, ureg->sirfsoc_int_en_reg,
rd_regl(port, ureg->sirfsoc_int_en_reg) |
SIRFUART_RX_DMA_INT_EN(uint_en,
sirfport->uart_reg->uart_type));
else
wr_regl(port, ureg->sirfsoc_int_en_reg,
SIRFUART_RX_DMA_INT_EN(uint_en,
sirfport->uart_reg->uart_type));
}
static unsigned int
sirfsoc_usp_calc_sample_div(unsigned long set_rate,
unsigned long ioclk_rate, unsigned long *sample_reg)
{
unsigned long min_delta = ~0UL;
unsigned short sample_div;
unsigned long ioclk_div = 0;
unsigned long temp_delta;
for (sample_div = SIRF_USP_MIN_SAMPLE_DIV;
sample_div <= SIRF_MAX_SAMPLE_DIV; sample_div++) {
temp_delta = ioclk_rate -
(ioclk_rate + (set_rate * sample_div) / 2)
/ (set_rate * sample_div) * set_rate * sample_div;
temp_delta = (temp_delta > 0) ? temp_delta : -temp_delta;
if (temp_delta < min_delta) {
ioclk_div = (2 * ioclk_rate /
(set_rate * sample_div) + 1) / 2 - 1;
if (ioclk_div > SIRF_IOCLK_DIV_MAX)
continue;
min_delta = temp_delta;
*sample_reg = sample_div;
if (!temp_delta)
break;
}
}
return ioclk_div;
}
static unsigned int
sirfsoc_uart_calc_sample_div(unsigned long baud_rate,
unsigned long ioclk_rate, unsigned long *set_baud)
{
unsigned long min_delta = ~0UL;
unsigned short sample_div;
unsigned int regv = 0;
unsigned long ioclk_div;
unsigned long baud_tmp;
int temp_delta;
for (sample_div = SIRF_MIN_SAMPLE_DIV;
sample_div <= SIRF_MAX_SAMPLE_DIV; sample_div++) {
ioclk_div = (ioclk_rate / (baud_rate * (sample_div + 1))) - 1;
if (ioclk_div > SIRF_IOCLK_DIV_MAX)
continue;
baud_tmp = ioclk_rate / ((ioclk_div + 1) * (sample_div + 1));
temp_delta = baud_tmp - baud_rate;
temp_delta = (temp_delta > 0) ? temp_delta : -temp_delta;
if (temp_delta < min_delta) {
regv = regv & (~SIRF_IOCLK_DIV_MASK);
regv = regv | ioclk_div;
regv = regv & (~SIRF_SAMPLE_DIV_MASK);
regv = regv | (sample_div << SIRF_SAMPLE_DIV_SHIFT);
min_delta = temp_delta;
*set_baud = baud_tmp;
}
}
return regv;
}
static void sirfsoc_uart_set_termios(struct uart_port *port,
struct ktermios *termios,
struct ktermios *old)
{
struct sirfsoc_uart_port *sirfport = to_sirfport(port);
struct sirfsoc_register *ureg = &sirfport->uart_reg->uart_reg;
struct sirfsoc_int_en *uint_en = &sirfport->uart_reg->uart_int_en;
unsigned long config_reg = 0;
unsigned long baud_rate;
unsigned long set_baud;
unsigned long flags;
unsigned long ic;
unsigned int clk_div_reg = 0;
unsigned long txfifo_op_reg, ioclk_rate;
unsigned long rx_time_out;
int threshold_div;
u32 data_bit_len, stop_bit_len, len_val;
unsigned long sample_div_reg = 0xf;
ioclk_rate = port->uartclk;
switch (termios->c_cflag & CSIZE) {
default:
case CS8:
data_bit_len = 8;
config_reg |= SIRFUART_DATA_BIT_LEN_8;
break;
case CS7:
data_bit_len = 7;
config_reg |= SIRFUART_DATA_BIT_LEN_7;
break;
case CS6:
data_bit_len = 6;
config_reg |= SIRFUART_DATA_BIT_LEN_6;
break;
case CS5:
data_bit_len = 5;
config_reg |= SIRFUART_DATA_BIT_LEN_5;
break;
}
if (termios->c_cflag & CSTOPB) {
config_reg |= SIRFUART_STOP_BIT_LEN_2;
stop_bit_len = 2;
} else
stop_bit_len = 1;
spin_lock_irqsave(&port->lock, flags);
port->read_status_mask = uint_en->sirfsoc_rx_oflow_en;
port->ignore_status_mask = 0;
if (sirfport->uart_reg->uart_type == SIRF_REAL_UART) {
if (termios->c_iflag & INPCK)
port->read_status_mask |= uint_en->sirfsoc_frm_err_en |
uint_en->sirfsoc_parity_err_en;
} else {
if (termios->c_iflag & INPCK)
port->read_status_mask |= uint_en->sirfsoc_frm_err_en;
}
if (termios->c_iflag & (IGNBRK | BRKINT | PARMRK))
port->read_status_mask |= uint_en->sirfsoc_rxd_brk_en;
if (sirfport->uart_reg->uart_type == SIRF_REAL_UART) {
if (termios->c_iflag & IGNPAR)
port->ignore_status_mask |=
uint_en->sirfsoc_frm_err_en |
uint_en->sirfsoc_parity_err_en;
if (termios->c_cflag & PARENB) {
if (termios->c_cflag & CMSPAR) {
if (termios->c_cflag & PARODD)
config_reg |= SIRFUART_STICK_BIT_MARK;
else
config_reg |= SIRFUART_STICK_BIT_SPACE;
} else {
if (termios->c_cflag & PARODD)
config_reg |= SIRFUART_STICK_BIT_ODD;
else
config_reg |= SIRFUART_STICK_BIT_EVEN;
}
}
} else {
if (termios->c_iflag & IGNPAR)
port->ignore_status_mask |=
uint_en->sirfsoc_frm_err_en;
if (termios->c_cflag & PARENB)
dev_warn(port->dev,
"USP-UART not support parity err\n");
}
if (termios->c_iflag & IGNBRK) {
port->ignore_status_mask |=
uint_en->sirfsoc_rxd_brk_en;
if (termios->c_iflag & IGNPAR)
port->ignore_status_mask |=
uint_en->sirfsoc_rx_oflow_en;
}
if ((termios->c_cflag & CREAD) == 0)
port->ignore_status_mask |= SIRFUART_DUMMY_READ;
/* Hardware Flow Control Settings */
if (UART_ENABLE_MS(port, termios->c_cflag)) {
if (!sirfport->ms_enabled)
sirfsoc_uart_enable_ms(port);
} else {
if (sirfport->ms_enabled)
sirfsoc_uart_disable_ms(port);
}
baud_rate = uart_get_baud_rate(port, termios, old, 0, 4000000);
if (ioclk_rate == 150000000) {
for (ic = 0; ic < SIRF_BAUD_RATE_SUPPORT_NR; ic++)
if (baud_rate == baudrate_to_regv[ic].baud_rate)
clk_div_reg = baudrate_to_regv[ic].reg_val;
}
set_baud = baud_rate;
if (sirfport->uart_reg->uart_type == SIRF_REAL_UART) {
if (unlikely(clk_div_reg == 0))
clk_div_reg = sirfsoc_uart_calc_sample_div(baud_rate,
ioclk_rate, &set_baud);
wr_regl(port, ureg->sirfsoc_divisor, clk_div_reg);
} else {
clk_div_reg = sirfsoc_usp_calc_sample_div(baud_rate,
ioclk_rate, &sample_div_reg);
sample_div_reg--;
set_baud = ((ioclk_rate / (clk_div_reg+1) - 1) /
(sample_div_reg + 1));
/* setting usp mode 2 */
len_val = ((1 << SIRFSOC_USP_MODE2_RXD_DELAY_OFFSET) |
(1 << SIRFSOC_USP_MODE2_TXD_DELAY_OFFSET));
len_val |= ((clk_div_reg & SIRFSOC_USP_MODE2_CLK_DIVISOR_MASK)
<< SIRFSOC_USP_MODE2_CLK_DIVISOR_OFFSET);
wr_regl(port, ureg->sirfsoc_mode2, len_val);
}
if (tty_termios_baud_rate(termios))
tty_termios_encode_baud_rate(termios, set_baud, set_baud);
/* set receive timeout && data bits len */
rx_time_out = SIRFSOC_UART_RX_TIMEOUT(set_baud, 20000);
rx_time_out = SIRFUART_RECV_TIMEOUT_VALUE(rx_time_out);
txfifo_op_reg = rd_regl(port, ureg->sirfsoc_tx_fifo_op);
wr_regl(port, ureg->sirfsoc_tx_fifo_op,
(txfifo_op_reg & ~SIRFUART_FIFO_START));
if (sirfport->uart_reg->uart_type == SIRF_REAL_UART) {
config_reg |= SIRFUART_UART_RECV_TIMEOUT(rx_time_out);
wr_regl(port, ureg->sirfsoc_line_ctrl, config_reg);
} else {
/*tx frame ctrl*/
len_val = (data_bit_len - 1) << SIRFSOC_USP_TX_DATA_LEN_OFFSET;
len_val |= (data_bit_len + 1 + stop_bit_len - 1) <<
SIRFSOC_USP_TX_FRAME_LEN_OFFSET;
len_val |= ((data_bit_len - 1) <<
SIRFSOC_USP_TX_SHIFTER_LEN_OFFSET);
len_val |= (((clk_div_reg & 0xc00) >> 10) <<
SIRFSOC_USP_TX_CLK_DIVISOR_OFFSET);
wr_regl(port, ureg->sirfsoc_tx_frame_ctrl, len_val);
/*rx frame ctrl*/
len_val = (data_bit_len - 1) << SIRFSOC_USP_RX_DATA_LEN_OFFSET;
len_val |= (data_bit_len + 1 + stop_bit_len - 1) <<
SIRFSOC_USP_RX_FRAME_LEN_OFFSET;
len_val |= (data_bit_len - 1) <<
SIRFSOC_USP_RX_SHIFTER_LEN_OFFSET;
len_val |= (((clk_div_reg & 0xf000) >> 12) <<
SIRFSOC_USP_RX_CLK_DIVISOR_OFFSET);
wr_regl(port, ureg->sirfsoc_rx_frame_ctrl, len_val);
/*async param*/
wr_regl(port, ureg->sirfsoc_async_param_reg,
(SIRFUART_USP_RECV_TIMEOUT(rx_time_out)) |
(sample_div_reg & SIRFSOC_USP_ASYNC_DIV2_MASK) <<
SIRFSOC_USP_ASYNC_DIV2_OFFSET);
}
if (sirfport->tx_dma_chan)
wr_regl(port, ureg->sirfsoc_tx_dma_io_ctrl, SIRFUART_DMA_MODE);
else
wr_regl(port, ureg->sirfsoc_tx_dma_io_ctrl, SIRFUART_IO_MODE);
if (sirfport->rx_dma_chan)
wr_regl(port, ureg->sirfsoc_rx_dma_io_ctrl,
rd_regl(port, ureg->sirfsoc_rx_dma_io_ctrl) &
~SIRFUART_IO_MODE);
else
wr_regl(port, ureg->sirfsoc_rx_dma_io_ctrl,
rd_regl(port, ureg->sirfsoc_rx_dma_io_ctrl) |
SIRFUART_IO_MODE);
sirfport->rx_period_time = 20000000;
/* Reset Rx/Tx FIFO Threshold level for proper baudrate */
if (set_baud < 1000000)
threshold_div = 1;
else
threshold_div = 2;
wr_regl(port, ureg->sirfsoc_tx_fifo_ctrl,
SIRFUART_FIFO_THD(port) / threshold_div);
wr_regl(port, ureg->sirfsoc_rx_fifo_ctrl,
SIRFUART_FIFO_THD(port) / threshold_div);
txfifo_op_reg |= SIRFUART_FIFO_START;
wr_regl(port, ureg->sirfsoc_tx_fifo_op, txfifo_op_reg);
uart_update_timeout(port, termios->c_cflag, set_baud);
wr_regl(port, ureg->sirfsoc_tx_rx_en, SIRFUART_TX_EN | SIRFUART_RX_EN);
spin_unlock_irqrestore(&port->lock, flags);
}
static void sirfsoc_uart_pm(struct uart_port *port, unsigned int state,
unsigned int oldstate)
{
struct sirfsoc_uart_port *sirfport = to_sirfport(port);
if (!state)
clk_prepare_enable(sirfport->clk);
else
clk_disable_unprepare(sirfport->clk);
}
static int sirfsoc_uart_startup(struct uart_port *port)
{
struct sirfsoc_uart_port *sirfport = to_sirfport(port);
struct sirfsoc_register *ureg = &sirfport->uart_reg->uart_reg;
struct sirfsoc_int_en *uint_en = &sirfport->uart_reg->uart_int_en;
unsigned int index = port->line;
int ret;
irq_modify_status(port->irq, IRQ_NOREQUEST, IRQ_NOAUTOEN);
ret = request_irq(port->irq,
sirfsoc_uart_isr,
0,
SIRFUART_PORT_NAME,
sirfport);
if (ret != 0) {
dev_err(port->dev, "UART%d request IRQ line (%d) failed.\n",
index, port->irq);
goto irq_err;
}
/* initial hardware settings */
wr_regl(port, ureg->sirfsoc_tx_dma_io_ctrl,
rd_regl(port, ureg->sirfsoc_tx_dma_io_ctrl) |
SIRFUART_IO_MODE);
wr_regl(port, ureg->sirfsoc_rx_dma_io_ctrl,
rd_regl(port, ureg->sirfsoc_rx_dma_io_ctrl) |
SIRFUART_IO_MODE);
wr_regl(port, ureg->sirfsoc_rx_dma_io_ctrl,
rd_regl(port, ureg->sirfsoc_rx_dma_io_ctrl) &
~SIRFUART_RX_DMA_FLUSH);
wr_regl(port, ureg->sirfsoc_tx_dma_io_len, 0);
wr_regl(port, ureg->sirfsoc_rx_dma_io_len, 0);
wr_regl(port, ureg->sirfsoc_tx_rx_en, SIRFUART_RX_EN | SIRFUART_TX_EN);
if (sirfport->uart_reg->uart_type == SIRF_USP_UART)
wr_regl(port, ureg->sirfsoc_mode1,
SIRFSOC_USP_ENDIAN_CTRL_LSBF |
SIRFSOC_USP_EN);
wr_regl(port, ureg->sirfsoc_tx_fifo_op, SIRFUART_FIFO_RESET);
wr_regl(port, ureg->sirfsoc_rx_fifo_op, SIRFUART_FIFO_RESET);
wr_regl(port, ureg->sirfsoc_rx_fifo_op, 0);
wr_regl(port, ureg->sirfsoc_tx_fifo_ctrl, SIRFUART_FIFO_THD(port));
wr_regl(port, ureg->sirfsoc_rx_fifo_ctrl, SIRFUART_FIFO_THD(port));
if (sirfport->rx_dma_chan)
wr_regl(port, ureg->sirfsoc_rx_fifo_level_chk,
SIRFUART_RX_FIFO_CHK_SC(port->line, 0x1) |
SIRFUART_RX_FIFO_CHK_LC(port->line, 0x2) |
SIRFUART_RX_FIFO_CHK_HC(port->line, 0x4));
if (sirfport->tx_dma_chan) {
sirfport->tx_dma_state = TX_DMA_IDLE;
wr_regl(port, ureg->sirfsoc_tx_fifo_level_chk,
SIRFUART_TX_FIFO_CHK_SC(port->line, 0x1b) |
SIRFUART_TX_FIFO_CHK_LC(port->line, 0xe) |
SIRFUART_TX_FIFO_CHK_HC(port->line, 0x4));
}
sirfport->ms_enabled = false;
if (sirfport->uart_reg->uart_type == SIRF_USP_UART &&
sirfport->hw_flow_ctrl) {
irq_modify_status(gpio_to_irq(sirfport->cts_gpio),
IRQ_NOREQUEST, IRQ_NOAUTOEN);
ret = request_irq(gpio_to_irq(sirfport->cts_gpio),
sirfsoc_uart_usp_cts_handler, IRQF_TRIGGER_FALLING |
IRQF_TRIGGER_RISING, "usp_cts_irq", sirfport);
if (ret != 0) {
dev_err(port->dev, "UART-USP:request gpio irq fail\n");
goto init_rx_err;
}
}
if (sirfport->uart_reg->uart_type == SIRF_REAL_UART &&
sirfport->rx_dma_chan)
wr_regl(port, ureg->sirfsoc_swh_dma_io,
SIRFUART_CLEAR_RX_ADDR_EN);
if (sirfport->uart_reg->uart_type == SIRF_USP_UART &&
sirfport->rx_dma_chan)
wr_regl(port, ureg->sirfsoc_rx_dma_io_ctrl,
rd_regl(port, ureg->sirfsoc_rx_dma_io_ctrl) |
SIRFSOC_USP_FRADDR_CLR_EN);
if (sirfport->rx_dma_chan && !sirfport->is_hrt_enabled) {
sirfport->is_hrt_enabled = true;
sirfport->rx_period_time = 20000000;
sirfport->rx_last_pos = -1;
sirfport->pio_fetch_cnt = 0;
sirfport->rx_dma_items.xmit.tail =
sirfport->rx_dma_items.xmit.head = 0;
hrtimer_start(&sirfport->hrt,
ns_to_ktime(sirfport->rx_period_time),
HRTIMER_MODE_REL);
}
wr_regl(port, ureg->sirfsoc_rx_fifo_op, SIRFUART_FIFO_START);
if (sirfport->rx_dma_chan)
sirfsoc_uart_start_next_rx_dma(port);
else {
if (!sirfport->is_atlas7)
wr_regl(port, ureg->sirfsoc_int_en_reg,
rd_regl(port, ureg->sirfsoc_int_en_reg) |
SIRFUART_RX_IO_INT_EN(uint_en,
sirfport->uart_reg->uart_type));
else
wr_regl(port, ureg->sirfsoc_int_en_reg,
SIRFUART_RX_IO_INT_EN(uint_en,
sirfport->uart_reg->uart_type));
}
enable_irq(port->irq);
return 0;
init_rx_err:
free_irq(port->irq, sirfport);
irq_err:
return ret;
}
static void sirfsoc_uart_shutdown(struct uart_port *port)
{
struct sirfsoc_uart_port *sirfport = to_sirfport(port);
struct sirfsoc_register *ureg = &sirfport->uart_reg->uart_reg;
struct circ_buf *xmit;
xmit = &sirfport->rx_dma_items.xmit;
if (!sirfport->is_atlas7)
wr_regl(port, ureg->sirfsoc_int_en_reg, 0);
else
wr_regl(port, ureg->sirfsoc_int_en_clr_reg, ~0UL);
free_irq(port->irq, sirfport);
if (sirfport->ms_enabled)
sirfsoc_uart_disable_ms(port);
if (sirfport->uart_reg->uart_type == SIRF_USP_UART &&
sirfport->hw_flow_ctrl) {
gpio_set_value(sirfport->rts_gpio, 1);
free_irq(gpio_to_irq(sirfport->cts_gpio), sirfport);
}
if (sirfport->tx_dma_chan)
sirfport->tx_dma_state = TX_DMA_IDLE;
if (sirfport->rx_dma_chan && sirfport->is_hrt_enabled) {
while (((rd_regl(port, ureg->sirfsoc_rx_fifo_status) &
SIRFUART_RX_FIFO_MASK) > sirfport->pio_fetch_cnt) &&
!CIRC_CNT(xmit->head, xmit->tail,
SIRFSOC_RX_DMA_BUF_SIZE))
;
sirfport->is_hrt_enabled = false;
hrtimer_cancel(&sirfport->hrt);
}
}
static const char *sirfsoc_uart_type(struct uart_port *port)
{
return port->type == SIRFSOC_PORT_TYPE ? SIRFUART_PORT_NAME : NULL;
}
static int sirfsoc_uart_request_port(struct uart_port *port)
{
struct sirfsoc_uart_port *sirfport = to_sirfport(port);
struct sirfsoc_uart_param *uart_param = &sirfport->uart_reg->uart_param;
void *ret;
ret = request_mem_region(port->mapbase,
SIRFUART_MAP_SIZE, uart_param->port_name);
return ret ? 0 : -EBUSY;
}
static void sirfsoc_uart_release_port(struct uart_port *port)
{
release_mem_region(port->mapbase, SIRFUART_MAP_SIZE);
}
static void sirfsoc_uart_config_port(struct uart_port *port, int flags)
{
if (flags & UART_CONFIG_TYPE) {
port->type = SIRFSOC_PORT_TYPE;
sirfsoc_uart_request_port(port);
}
}
static struct uart_ops sirfsoc_uart_ops = {
.tx_empty = sirfsoc_uart_tx_empty,
.get_mctrl = sirfsoc_uart_get_mctrl,
.set_mctrl = sirfsoc_uart_set_mctrl,
.stop_tx = sirfsoc_uart_stop_tx,
.start_tx = sirfsoc_uart_start_tx,
.stop_rx = sirfsoc_uart_stop_rx,
.enable_ms = sirfsoc_uart_enable_ms,
.break_ctl = sirfsoc_uart_break_ctl,
.startup = sirfsoc_uart_startup,
.shutdown = sirfsoc_uart_shutdown,
.set_termios = sirfsoc_uart_set_termios,
.pm = sirfsoc_uart_pm,
.type = sirfsoc_uart_type,
.release_port = sirfsoc_uart_release_port,
.request_port = sirfsoc_uart_request_port,
.config_port = sirfsoc_uart_config_port,
};
#ifdef CONFIG_SERIAL_SIRFSOC_CONSOLE
static int __init
sirfsoc_uart_console_setup(struct console *co, char *options)
{
unsigned int baud = 115200;
unsigned int bits = 8;
unsigned int parity = 'n';
unsigned int flow = 'n';
struct sirfsoc_uart_port *sirfport;
struct sirfsoc_register *ureg;
if (co->index < 0 || co->index >= SIRFSOC_UART_NR)
co->index = 1;
sirfport = sirf_ports[co->index];
if (!sirfport)
return -ENODEV;
ureg = &sirfport->uart_reg->uart_reg;
if (!sirfport->port.mapbase)
return -ENODEV;
/* enable usp in mode1 register */
if (sirfport->uart_reg->uart_type == SIRF_USP_UART)
wr_regl(&sirfport->port, ureg->sirfsoc_mode1, SIRFSOC_USP_EN |
SIRFSOC_USP_ENDIAN_CTRL_LSBF);
if (options)
uart_parse_options(options, &baud, &parity, &bits, &flow);
sirfport->port.cons = co;
/* default console tx/rx transfer using io mode */
sirfport->rx_dma_chan = NULL;
sirfport->tx_dma_chan = NULL;
return uart_set_options(&sirfport->port, co, baud, parity, bits, flow);
}
static void sirfsoc_uart_console_putchar(struct uart_port *port, int ch)
{
struct sirfsoc_uart_port *sirfport = to_sirfport(port);
struct sirfsoc_register *ureg = &sirfport->uart_reg->uart_reg;
struct sirfsoc_fifo_status *ufifo_st = &sirfport->uart_reg->fifo_status;
while (rd_regl(port, ureg->sirfsoc_tx_fifo_status) &
ufifo_st->ff_full(port))
cpu_relax();
wr_regl(port, ureg->sirfsoc_tx_fifo_data, ch);
}
static void sirfsoc_uart_console_write(struct console *co, const char *s,
unsigned int count)
{
struct sirfsoc_uart_port *sirfport = sirf_ports[co->index];
uart_console_write(&sirfport->port, s, count,
sirfsoc_uart_console_putchar);
}
static struct console sirfsoc_uart_console = {
.name = SIRFSOC_UART_NAME,
.device = uart_console_device,
.flags = CON_PRINTBUFFER,
.index = -1,
.write = sirfsoc_uart_console_write,
.setup = sirfsoc_uart_console_setup,
.data = &sirfsoc_uart_drv,
};
static int __init sirfsoc_uart_console_init(void)
{
register_console(&sirfsoc_uart_console);
return 0;
}
console_initcall(sirfsoc_uart_console_init);
#endif
static struct uart_driver sirfsoc_uart_drv = {
.owner = THIS_MODULE,
.driver_name = SIRFUART_PORT_NAME,
.nr = SIRFSOC_UART_NR,
.dev_name = SIRFSOC_UART_NAME,
.major = SIRFSOC_UART_MAJOR,
.minor = SIRFSOC_UART_MINOR,
#ifdef CONFIG_SERIAL_SIRFSOC_CONSOLE
.cons = &sirfsoc_uart_console,
#else
.cons = NULL,
#endif
};
static enum hrtimer_restart
sirfsoc_uart_rx_dma_hrtimer_callback(struct hrtimer *hrt)
{
struct sirfsoc_uart_port *sirfport;
struct uart_port *port;
int count, inserted;
struct dma_tx_state tx_state;
struct tty_struct *tty;
struct sirfsoc_register *ureg;
struct circ_buf *xmit;
struct sirfsoc_fifo_status *ufifo_st;
int max_pio_cnt;
sirfport = container_of(hrt, struct sirfsoc_uart_port, hrt);
port = &sirfport->port;
inserted = 0;
tty = port->state->port.tty;
ureg = &sirfport->uart_reg->uart_reg;
xmit = &sirfport->rx_dma_items.xmit;
ufifo_st = &sirfport->uart_reg->fifo_status;
dmaengine_tx_status(sirfport->rx_dma_chan,
sirfport->rx_dma_items.cookie, &tx_state);
if (SIRFSOC_RX_DMA_BUF_SIZE - tx_state.residue !=
sirfport->rx_last_pos) {
xmit->head = SIRFSOC_RX_DMA_BUF_SIZE - tx_state.residue;
sirfport->rx_last_pos = xmit->head;
sirfport->pio_fetch_cnt = 0;
}
count = CIRC_CNT_TO_END(xmit->head, xmit->tail,
SIRFSOC_RX_DMA_BUF_SIZE);
while (count > 0) {
inserted = tty_insert_flip_string(tty->port,
(const unsigned char *)&xmit->buf[xmit->tail], count);
if (!inserted)
goto next_hrt;
port->icount.rx += inserted;
xmit->tail = (xmit->tail + inserted) &
(SIRFSOC_RX_DMA_BUF_SIZE - 1);
count = CIRC_CNT_TO_END(xmit->head, xmit->tail,
SIRFSOC_RX_DMA_BUF_SIZE);
tty_flip_buffer_push(tty->port);
}
/*
* if RX DMA buffer data have all push into tty buffer, and there is
* only little data(less than a dma transfer unit) left in rxfifo,
* fetch it out in pio mode and switch back to dma immediately
*/
if (!inserted && !count &&
((rd_regl(port, ureg->sirfsoc_rx_fifo_status) &
SIRFUART_RX_FIFO_MASK) > sirfport->pio_fetch_cnt)) {
dmaengine_pause(sirfport->rx_dma_chan);
/* switch to pio mode */
wr_regl(port, ureg->sirfsoc_rx_dma_io_ctrl,
rd_regl(port, ureg->sirfsoc_rx_dma_io_ctrl) |
SIRFUART_IO_MODE);
/*
* UART controller SWH_DMA_IO register have CLEAR_RX_ADDR_EN
* When found changing I/O to DMA mode, it clears
* two low bits of read point;
* USP have similar FRADDR_CLR_EN bit in USP_RX_DMA_IO_CTRL.
* Fetch data out from rxfifo into DMA buffer in PIO mode,
* while switch back to DMA mode, the data fetched will override
* by DMA, as hardware have a strange behaviour:
* after switch back to DMA mode, check rxfifo status it will
* be the number PIO fetched, so record the fetched data count
* to avoid the repeated fetch
*/
max_pio_cnt = 3;
while (!(rd_regl(port, ureg->sirfsoc_rx_fifo_status) &
ufifo_st->ff_empty(port)) && max_pio_cnt--) {
xmit->buf[xmit->head] =
rd_regl(port, ureg->sirfsoc_rx_fifo_data);
xmit->head = (xmit->head + 1) &
(SIRFSOC_RX_DMA_BUF_SIZE - 1);
sirfport->pio_fetch_cnt++;
}
/* switch back to dma mode */
wr_regl(port, ureg->sirfsoc_rx_dma_io_ctrl,
rd_regl(port, ureg->sirfsoc_rx_dma_io_ctrl) &
~SIRFUART_IO_MODE);
dmaengine_resume(sirfport->rx_dma_chan);
}
next_hrt:
hrtimer_forward_now(hrt, ns_to_ktime(sirfport->rx_period_time));
return HRTIMER_RESTART;
}
static struct of_device_id sirfsoc_uart_ids[] = {
{ .compatible = "sirf,prima2-uart", .data = &sirfsoc_uart,},
{ .compatible = "sirf,atlas7-uart", .data = &sirfsoc_uart},
{ .compatible = "sirf,prima2-usp-uart", .data = &sirfsoc_usp},
{ .compatible = "sirf,atlas7-usp-uart", .data = &sirfsoc_usp},
{}
};
MODULE_DEVICE_TABLE(of, sirfsoc_uart_ids);
static int sirfsoc_uart_probe(struct platform_device *pdev)
{
struct sirfsoc_uart_port *sirfport;
struct uart_port *port;
struct resource *res;
int ret;
struct dma_slave_config slv_cfg = {
.src_maxburst = 1,
};
struct dma_slave_config tx_slv_cfg = {
.dst_maxburst = 2,
};
const struct of_device_id *match;
match = of_match_node(sirfsoc_uart_ids, pdev->dev.of_node);
sirfport = devm_kzalloc(&pdev->dev, sizeof(*sirfport), GFP_KERNEL);
if (!sirfport) {
ret = -ENOMEM;
goto err;
}
sirfport->port.line = of_alias_get_id(pdev->dev.of_node, "serial");
sirf_ports[sirfport->port.line] = sirfport;
sirfport->port.iotype = UPIO_MEM;
sirfport->port.flags = UPF_BOOT_AUTOCONF;
port = &sirfport->port;
port->dev = &pdev->dev;
port->private_data = sirfport;
sirfport->uart_reg = (struct sirfsoc_uart_register *)match->data;
sirfport->hw_flow_ctrl = of_property_read_bool(pdev->dev.of_node,
"sirf,uart-has-rtscts");
if (of_device_is_compatible(pdev->dev.of_node, "sirf,prima2-uart") ||
of_device_is_compatible(pdev->dev.of_node, "sirf,atlas7-uart"))
sirfport->uart_reg->uart_type = SIRF_REAL_UART;
if (of_device_is_compatible(pdev->dev.of_node,
"sirf,prima2-usp-uart") || of_device_is_compatible(
pdev->dev.of_node, "sirf,atlas7-usp-uart")) {
sirfport->uart_reg->uart_type = SIRF_USP_UART;
if (!sirfport->hw_flow_ctrl)
goto usp_no_flow_control;
if (of_find_property(pdev->dev.of_node, "cts-gpios", NULL))
sirfport->cts_gpio = of_get_named_gpio(
pdev->dev.of_node, "cts-gpios", 0);
else
sirfport->cts_gpio = -1;
if (of_find_property(pdev->dev.of_node, "rts-gpios", NULL))
sirfport->rts_gpio = of_get_named_gpio(
pdev->dev.of_node, "rts-gpios", 0);
else
sirfport->rts_gpio = -1;
if ((!gpio_is_valid(sirfport->cts_gpio) ||
!gpio_is_valid(sirfport->rts_gpio))) {
ret = -EINVAL;
dev_err(&pdev->dev,
"Usp flow control must have cts and rts gpio");
goto err;
}
ret = devm_gpio_request(&pdev->dev, sirfport->cts_gpio,
"usp-cts-gpio");
if (ret) {
dev_err(&pdev->dev, "Unable request cts gpio");
goto err;
}
gpio_direction_input(sirfport->cts_gpio);
ret = devm_gpio_request(&pdev->dev, sirfport->rts_gpio,
"usp-rts-gpio");
if (ret) {
dev_err(&pdev->dev, "Unable request rts gpio");
goto err;
}
gpio_direction_output(sirfport->rts_gpio, 1);
}
usp_no_flow_control:
if (of_device_is_compatible(pdev->dev.of_node, "sirf,atlas7-uart") ||
of_device_is_compatible(pdev->dev.of_node, "sirf,atlas7-usp-uart"))
sirfport->is_atlas7 = true;
if (of_property_read_u32(pdev->dev.of_node,
"fifosize",
&port->fifosize)) {
dev_err(&pdev->dev,
"Unable to find fifosize in uart node.\n");
ret = -EFAULT;
goto err;
}
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
if (res == NULL) {
dev_err(&pdev->dev, "Insufficient resources.\n");
ret = -EFAULT;
goto err;
}
port->mapbase = res->start;
port->membase = devm_ioremap(&pdev->dev,
res->start, resource_size(res));
if (!port->membase) {
dev_err(&pdev->dev, "Cannot remap resource.\n");
ret = -ENOMEM;
goto err;
}
res = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
if (res == NULL) {
dev_err(&pdev->dev, "Insufficient resources.\n");
ret = -EFAULT;
goto err;
}
port->irq = res->start;
sirfport->clk = devm_clk_get(&pdev->dev, NULL);
if (IS_ERR(sirfport->clk)) {
ret = PTR_ERR(sirfport->clk);
goto err;
}
port->uartclk = clk_get_rate(sirfport->clk);
port->ops = &sirfsoc_uart_ops;
spin_lock_init(&port->lock);
platform_set_drvdata(pdev, sirfport);
ret = uart_add_one_port(&sirfsoc_uart_drv, port);
if (ret != 0) {
dev_err(&pdev->dev, "Cannot add UART port(%d).\n", pdev->id);
goto err;
}
sirfport->rx_dma_chan = dma_request_slave_channel(port->dev, "rx");
sirfport->rx_dma_items.xmit.buf =
dma_alloc_coherent(port->dev, SIRFSOC_RX_DMA_BUF_SIZE,
&sirfport->rx_dma_items.dma_addr, GFP_KERNEL);
if (!sirfport->rx_dma_items.xmit.buf) {
dev_err(port->dev, "Uart alloc bufa failed\n");
ret = -ENOMEM;
goto alloc_coherent_err;
}
sirfport->rx_dma_items.xmit.head =
sirfport->rx_dma_items.xmit.tail = 0;
if (sirfport->rx_dma_chan)
dmaengine_slave_config(sirfport->rx_dma_chan, &slv_cfg);
sirfport->tx_dma_chan = dma_request_slave_channel(port->dev, "tx");
if (sirfport->tx_dma_chan)
dmaengine_slave_config(sirfport->tx_dma_chan, &tx_slv_cfg);
if (sirfport->rx_dma_chan) {
hrtimer_init(&sirfport->hrt, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
sirfport->hrt.function = sirfsoc_uart_rx_dma_hrtimer_callback;
sirfport->is_hrt_enabled = false;
}
return 0;
alloc_coherent_err:
dma_free_coherent(port->dev, SIRFSOC_RX_DMA_BUF_SIZE,
sirfport->rx_dma_items.xmit.buf,
sirfport->rx_dma_items.dma_addr);
dma_release_channel(sirfport->rx_dma_chan);
err:
return ret;
}
static int sirfsoc_uart_remove(struct platform_device *pdev)
{
struct sirfsoc_uart_port *sirfport = platform_get_drvdata(pdev);
struct uart_port *port = &sirfport->port;
uart_remove_one_port(&sirfsoc_uart_drv, port);
if (sirfport->rx_dma_chan) {
dmaengine_terminate_all(sirfport->rx_dma_chan);
dma_release_channel(sirfport->rx_dma_chan);
dma_free_coherent(port->dev, SIRFSOC_RX_DMA_BUF_SIZE,
sirfport->rx_dma_items.xmit.buf,
sirfport->rx_dma_items.dma_addr);
}
if (sirfport->tx_dma_chan) {
dmaengine_terminate_all(sirfport->tx_dma_chan);
dma_release_channel(sirfport->tx_dma_chan);
}
return 0;
}
#ifdef CONFIG_PM_SLEEP
static int
sirfsoc_uart_suspend(struct device *pdev)
{
struct sirfsoc_uart_port *sirfport = dev_get_drvdata(pdev);
struct uart_port *port = &sirfport->port;
uart_suspend_port(&sirfsoc_uart_drv, port);
return 0;
}
static int sirfsoc_uart_resume(struct device *pdev)
{
struct sirfsoc_uart_port *sirfport = dev_get_drvdata(pdev);
struct uart_port *port = &sirfport->port;
uart_resume_port(&sirfsoc_uart_drv, port);
return 0;
}
#endif
static const struct dev_pm_ops sirfsoc_uart_pm_ops = {
SET_SYSTEM_SLEEP_PM_OPS(sirfsoc_uart_suspend, sirfsoc_uart_resume)
};
static struct platform_driver sirfsoc_uart_driver = {
.probe = sirfsoc_uart_probe,
.remove = sirfsoc_uart_remove,
.driver = {
.name = SIRFUART_PORT_NAME,
.of_match_table = sirfsoc_uart_ids,
.pm = &sirfsoc_uart_pm_ops,
},
};
static int __init sirfsoc_uart_init(void)
{
int ret = 0;
ret = uart_register_driver(&sirfsoc_uart_drv);
if (ret)
goto out;
ret = platform_driver_register(&sirfsoc_uart_driver);
if (ret)
uart_unregister_driver(&sirfsoc_uart_drv);
out:
return ret;
}
module_init(sirfsoc_uart_init);
static void __exit sirfsoc_uart_exit(void)
{
platform_driver_unregister(&sirfsoc_uart_driver);
uart_unregister_driver(&sirfsoc_uart_drv);
}
module_exit(sirfsoc_uart_exit);
MODULE_LICENSE("GPL v2");
MODULE_AUTHOR("Bin Shi <Bin.Shi@csr.com>, Rong Wang<Rong.Wang@csr.com>");
MODULE_DESCRIPTION("CSR SiRFprimaII Uart Driver");