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linux-zen-desktop/drivers/tty/serial/samsung_tty.c

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// SPDX-License-Identifier: GPL-2.0
/*
* Driver core for Samsung SoC onboard UARTs.
*
* Ben Dooks, Copyright (c) 2003-2008 Simtec Electronics
* http://armlinux.simtec.co.uk/
*/
/* Note on 2410 error handling
*
* The s3c2410 manual has a love/hate affair with the contents of the
* UERSTAT register in the UART blocks, and keeps marking some of the
* error bits as reserved. Having checked with the s3c2410x01,
* it copes with BREAKs properly, so I am happy to ignore the RESERVED
* feature from the latter versions of the manual.
*
* If it becomes aparrent that latter versions of the 2410 remove these
* bits, then action will have to be taken to differentiate the versions
* and change the policy on BREAK
*
* BJD, 04-Nov-2004
*/
#include <linux/dmaengine.h>
#include <linux/dma-mapping.h>
#include <linux/slab.h>
#include <linux/math.h>
#include <linux/module.h>
#include <linux/ioport.h>
#include <linux/io.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/serial_s3c.h>
#include <linux/delay.h>
#include <linux/clk.h>
#include <linux/cpufreq.h>
#include <linux/of.h>
#include <asm/irq.h>
/* UART name and device definitions */
#define S3C24XX_SERIAL_NAME "ttySAC"
#define S3C24XX_SERIAL_MAJOR 204
#define S3C24XX_SERIAL_MINOR 64
#ifdef CONFIG_ARM64
#define UART_NR 12
#else
#define UART_NR CONFIG_SERIAL_SAMSUNG_UARTS
#endif
#define S3C24XX_TX_PIO 1
#define S3C24XX_TX_DMA 2
#define S3C24XX_RX_PIO 1
#define S3C24XX_RX_DMA 2
/* flag to ignore all characters coming in */
#define RXSTAT_DUMMY_READ (0x10000000)
enum s3c24xx_port_type {
TYPE_S3C24XX,
TYPE_S3C6400,
TYPE_APPLE_S5L,
};
struct s3c24xx_uart_info {
const char *name;
enum s3c24xx_port_type type;
unsigned int port_type;
unsigned int fifosize;
unsigned long rx_fifomask;
unsigned long rx_fifoshift;
unsigned long rx_fifofull;
unsigned long tx_fifomask;
unsigned long tx_fifoshift;
unsigned long tx_fifofull;
unsigned int def_clk_sel;
unsigned long num_clks;
unsigned long clksel_mask;
unsigned long clksel_shift;
unsigned long ucon_mask;
/* uart port features */
unsigned int has_divslot:1;
};
struct s3c24xx_serial_drv_data {
const struct s3c24xx_uart_info info;
const struct s3c2410_uartcfg def_cfg;
const unsigned int fifosize[UART_NR];
};
struct s3c24xx_uart_dma {
unsigned int rx_chan_id;
unsigned int tx_chan_id;
struct dma_slave_config rx_conf;
struct dma_slave_config tx_conf;
struct dma_chan *rx_chan;
struct dma_chan *tx_chan;
dma_addr_t rx_addr;
dma_addr_t tx_addr;
dma_cookie_t rx_cookie;
dma_cookie_t tx_cookie;
char *rx_buf;
dma_addr_t tx_transfer_addr;
size_t rx_size;
size_t tx_size;
struct dma_async_tx_descriptor *tx_desc;
struct dma_async_tx_descriptor *rx_desc;
int tx_bytes_requested;
int rx_bytes_requested;
};
struct s3c24xx_uart_port {
unsigned char rx_claimed;
unsigned char tx_claimed;
unsigned char rx_enabled;
unsigned char tx_enabled;
unsigned int pm_level;
unsigned long baudclk_rate;
unsigned int min_dma_size;
unsigned int rx_irq;
unsigned int tx_irq;
unsigned int tx_in_progress;
unsigned int tx_mode;
unsigned int rx_mode;
const struct s3c24xx_uart_info *info;
struct clk *clk;
struct clk *baudclk;
struct uart_port port;
const struct s3c24xx_serial_drv_data *drv_data;
/* reference to platform data */
const struct s3c2410_uartcfg *cfg;
struct s3c24xx_uart_dma *dma;
};
static void s3c24xx_serial_tx_chars(struct s3c24xx_uart_port *ourport);
/* conversion functions */
#define s3c24xx_dev_to_port(__dev) dev_get_drvdata(__dev)
/* register access controls */
#define portaddr(port, reg) ((port)->membase + (reg))
#define portaddrl(port, reg) \
((unsigned long *)(unsigned long)((port)->membase + (reg)))
static u32 rd_reg(const struct uart_port *port, u32 reg)
{
switch (port->iotype) {
case UPIO_MEM:
return readb_relaxed(portaddr(port, reg));
case UPIO_MEM32:
return readl_relaxed(portaddr(port, reg));
default:
return 0;
}
return 0;
}
#define rd_regl(port, reg) (readl_relaxed(portaddr(port, reg)))
static void wr_reg(const struct uart_port *port, u32 reg, u32 val)
{
switch (port->iotype) {
case UPIO_MEM:
writeb_relaxed(val, portaddr(port, reg));
break;
case UPIO_MEM32:
writel_relaxed(val, portaddr(port, reg));
break;
}
}
#define wr_regl(port, reg, val) writel_relaxed(val, portaddr(port, reg))
/* Byte-order aware bit setting/clearing functions. */
static inline void s3c24xx_set_bit(const struct uart_port *port, int idx,
unsigned int reg)
{
unsigned long flags;
u32 val;
local_irq_save(flags);
val = rd_regl(port, reg);
val |= (1 << idx);
wr_regl(port, reg, val);
local_irq_restore(flags);
}
static inline void s3c24xx_clear_bit(const struct uart_port *port, int idx,
unsigned int reg)
{
unsigned long flags;
u32 val;
local_irq_save(flags);
val = rd_regl(port, reg);
val &= ~(1 << idx);
wr_regl(port, reg, val);
local_irq_restore(flags);
}
static inline struct s3c24xx_uart_port *to_ourport(struct uart_port *port)
{
return container_of(port, struct s3c24xx_uart_port, port);
}
/* translate a port to the device name */
static inline const char *s3c24xx_serial_portname(const struct uart_port *port)
{
return to_platform_device(port->dev)->name;
}
static int s3c24xx_serial_txempty_nofifo(const struct uart_port *port)
{
return rd_regl(port, S3C2410_UTRSTAT) & S3C2410_UTRSTAT_TXE;
}
static void s3c24xx_serial_rx_enable(struct uart_port *port)
{
struct s3c24xx_uart_port *ourport = to_ourport(port);
unsigned long flags;
unsigned int ucon, ufcon;
int count = 10000;
spin_lock_irqsave(&port->lock, flags);
while (--count && !s3c24xx_serial_txempty_nofifo(port))
udelay(100);
ufcon = rd_regl(port, S3C2410_UFCON);
ufcon |= S3C2410_UFCON_RESETRX;
wr_regl(port, S3C2410_UFCON, ufcon);
ucon = rd_regl(port, S3C2410_UCON);
ucon |= S3C2410_UCON_RXIRQMODE;
wr_regl(port, S3C2410_UCON, ucon);
ourport->rx_enabled = 1;
spin_unlock_irqrestore(&port->lock, flags);
}
static void s3c24xx_serial_rx_disable(struct uart_port *port)
{
struct s3c24xx_uart_port *ourport = to_ourport(port);
unsigned long flags;
unsigned int ucon;
spin_lock_irqsave(&port->lock, flags);
ucon = rd_regl(port, S3C2410_UCON);
ucon &= ~S3C2410_UCON_RXIRQMODE;
wr_regl(port, S3C2410_UCON, ucon);
ourport->rx_enabled = 0;
spin_unlock_irqrestore(&port->lock, flags);
}
static void s3c24xx_serial_stop_tx(struct uart_port *port)
{
struct s3c24xx_uart_port *ourport = to_ourport(port);
struct s3c24xx_uart_dma *dma = ourport->dma;
struct dma_tx_state state;
int count;
if (!ourport->tx_enabled)
return;
switch (ourport->info->type) {
case TYPE_S3C6400:
s3c24xx_set_bit(port, S3C64XX_UINTM_TXD, S3C64XX_UINTM);
break;
case TYPE_APPLE_S5L:
s3c24xx_clear_bit(port, APPLE_S5L_UCON_TXTHRESH_ENA, S3C2410_UCON);
break;
default:
disable_irq_nosync(ourport->tx_irq);
break;
}
if (dma && dma->tx_chan && ourport->tx_in_progress == S3C24XX_TX_DMA) {
dmaengine_pause(dma->tx_chan);
dmaengine_tx_status(dma->tx_chan, dma->tx_cookie, &state);
dmaengine_terminate_all(dma->tx_chan);
dma_sync_single_for_cpu(dma->tx_chan->device->dev,
dma->tx_transfer_addr, dma->tx_size,
DMA_TO_DEVICE);
async_tx_ack(dma->tx_desc);
count = dma->tx_bytes_requested - state.residue;
uart_xmit_advance(port, count);
}
ourport->tx_enabled = 0;
ourport->tx_in_progress = 0;
if (port->flags & UPF_CONS_FLOW)
s3c24xx_serial_rx_enable(port);
ourport->tx_mode = 0;
}
static void s3c24xx_serial_start_next_tx(struct s3c24xx_uart_port *ourport);
static void s3c24xx_serial_tx_dma_complete(void *args)
{
struct s3c24xx_uart_port *ourport = args;
struct uart_port *port = &ourport->port;
struct circ_buf *xmit = &port->state->xmit;
struct s3c24xx_uart_dma *dma = ourport->dma;
struct dma_tx_state state;
unsigned long flags;
int count;
dmaengine_tx_status(dma->tx_chan, dma->tx_cookie, &state);
count = dma->tx_bytes_requested - state.residue;
async_tx_ack(dma->tx_desc);
dma_sync_single_for_cpu(dma->tx_chan->device->dev,
dma->tx_transfer_addr, dma->tx_size,
DMA_TO_DEVICE);
spin_lock_irqsave(&port->lock, flags);
uart_xmit_advance(port, count);
ourport->tx_in_progress = 0;
if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
uart_write_wakeup(port);
s3c24xx_serial_start_next_tx(ourport);
spin_unlock_irqrestore(&port->lock, flags);
}
static void enable_tx_dma(struct s3c24xx_uart_port *ourport)
{
const struct uart_port *port = &ourport->port;
u32 ucon;
/* Mask Tx interrupt */
switch (ourport->info->type) {
case TYPE_S3C6400:
s3c24xx_set_bit(port, S3C64XX_UINTM_TXD, S3C64XX_UINTM);
break;
case TYPE_APPLE_S5L:
WARN_ON(1); // No DMA
break;
default:
disable_irq_nosync(ourport->tx_irq);
break;
}
/* Enable tx dma mode */
ucon = rd_regl(port, S3C2410_UCON);
ucon &= ~(S3C64XX_UCON_TXBURST_MASK | S3C64XX_UCON_TXMODE_MASK);
ucon |= S3C64XX_UCON_TXBURST_1;
ucon |= S3C64XX_UCON_TXMODE_DMA;
wr_regl(port, S3C2410_UCON, ucon);
ourport->tx_mode = S3C24XX_TX_DMA;
}
static void enable_tx_pio(struct s3c24xx_uart_port *ourport)
{
const struct uart_port *port = &ourport->port;
u32 ucon, ufcon;
/* Set ufcon txtrig */
ourport->tx_in_progress = S3C24XX_TX_PIO;
ufcon = rd_regl(port, S3C2410_UFCON);
wr_regl(port, S3C2410_UFCON, ufcon);
/* Enable tx pio mode */
ucon = rd_regl(port, S3C2410_UCON);
ucon &= ~(S3C64XX_UCON_TXMODE_MASK);
ucon |= S3C64XX_UCON_TXMODE_CPU;
wr_regl(port, S3C2410_UCON, ucon);
/* Unmask Tx interrupt */
switch (ourport->info->type) {
case TYPE_S3C6400:
s3c24xx_clear_bit(port, S3C64XX_UINTM_TXD,
S3C64XX_UINTM);
break;
case TYPE_APPLE_S5L:
ucon |= APPLE_S5L_UCON_TXTHRESH_ENA_MSK;
wr_regl(port, S3C2410_UCON, ucon);
break;
default:
enable_irq(ourport->tx_irq);
break;
}
ourport->tx_mode = S3C24XX_TX_PIO;
/*
* The Apple version only has edge triggered TX IRQs, so we need
* to kick off the process by sending some characters here.
*/
if (ourport->info->type == TYPE_APPLE_S5L)
s3c24xx_serial_tx_chars(ourport);
}
static void s3c24xx_serial_start_tx_pio(struct s3c24xx_uart_port *ourport)
{
if (ourport->tx_mode != S3C24XX_TX_PIO)
enable_tx_pio(ourport);
}
static int s3c24xx_serial_start_tx_dma(struct s3c24xx_uart_port *ourport,
unsigned int count)
{
struct uart_port *port = &ourport->port;
struct circ_buf *xmit = &port->state->xmit;
struct s3c24xx_uart_dma *dma = ourport->dma;
if (ourport->tx_mode != S3C24XX_TX_DMA)
enable_tx_dma(ourport);
dma->tx_size = count & ~(dma_get_cache_alignment() - 1);
dma->tx_transfer_addr = dma->tx_addr + xmit->tail;
dma_sync_single_for_device(dma->tx_chan->device->dev,
dma->tx_transfer_addr, dma->tx_size,
DMA_TO_DEVICE);
dma->tx_desc = dmaengine_prep_slave_single(dma->tx_chan,
dma->tx_transfer_addr, dma->tx_size,
DMA_MEM_TO_DEV, DMA_PREP_INTERRUPT);
if (!dma->tx_desc) {
dev_err(ourport->port.dev, "Unable to get desc for Tx\n");
return -EIO;
}
dma->tx_desc->callback = s3c24xx_serial_tx_dma_complete;
dma->tx_desc->callback_param = ourport;
dma->tx_bytes_requested = dma->tx_size;
ourport->tx_in_progress = S3C24XX_TX_DMA;
dma->tx_cookie = dmaengine_submit(dma->tx_desc);
dma_async_issue_pending(dma->tx_chan);
return 0;
}
static void s3c24xx_serial_start_next_tx(struct s3c24xx_uart_port *ourport)
{
struct uart_port *port = &ourport->port;
struct circ_buf *xmit = &port->state->xmit;
unsigned long count;
/* Get data size up to the end of buffer */
count = CIRC_CNT_TO_END(xmit->head, xmit->tail, UART_XMIT_SIZE);
if (!count) {
s3c24xx_serial_stop_tx(port);
return;
}
if (!ourport->dma || !ourport->dma->tx_chan ||
count < ourport->min_dma_size ||
xmit->tail & (dma_get_cache_alignment() - 1))
s3c24xx_serial_start_tx_pio(ourport);
else
s3c24xx_serial_start_tx_dma(ourport, count);
}
static void s3c24xx_serial_start_tx(struct uart_port *port)
{
struct s3c24xx_uart_port *ourport = to_ourport(port);
struct circ_buf *xmit = &port->state->xmit;
if (!ourport->tx_enabled) {
if (port->flags & UPF_CONS_FLOW)
s3c24xx_serial_rx_disable(port);
ourport->tx_enabled = 1;
if (!ourport->dma || !ourport->dma->tx_chan)
s3c24xx_serial_start_tx_pio(ourport);
}
if (ourport->dma && ourport->dma->tx_chan) {
if (!uart_circ_empty(xmit) && !ourport->tx_in_progress)
s3c24xx_serial_start_next_tx(ourport);
}
}
static void s3c24xx_uart_copy_rx_to_tty(struct s3c24xx_uart_port *ourport,
struct tty_port *tty, int count)
{
struct s3c24xx_uart_dma *dma = ourport->dma;
int copied;
if (!count)
return;
dma_sync_single_for_cpu(dma->rx_chan->device->dev, dma->rx_addr,
dma->rx_size, DMA_FROM_DEVICE);
ourport->port.icount.rx += count;
if (!tty) {
dev_err(ourport->port.dev, "No tty port\n");
return;
}
copied = tty_insert_flip_string(tty,
((unsigned char *)(ourport->dma->rx_buf)), count);
if (copied != count) {
WARN_ON(1);
dev_err(ourport->port.dev, "RxData copy to tty layer failed\n");
}
}
static void s3c24xx_serial_stop_rx(struct uart_port *port)
{
struct s3c24xx_uart_port *ourport = to_ourport(port);
struct s3c24xx_uart_dma *dma = ourport->dma;
struct tty_port *t = &port->state->port;
struct dma_tx_state state;
enum dma_status dma_status;
unsigned int received;
if (ourport->rx_enabled) {
dev_dbg(port->dev, "stopping rx\n");
switch (ourport->info->type) {
case TYPE_S3C6400:
s3c24xx_set_bit(port, S3C64XX_UINTM_RXD,
S3C64XX_UINTM);
break;
case TYPE_APPLE_S5L:
s3c24xx_clear_bit(port, APPLE_S5L_UCON_RXTHRESH_ENA, S3C2410_UCON);
s3c24xx_clear_bit(port, APPLE_S5L_UCON_RXTO_ENA, S3C2410_UCON);
break;
default:
disable_irq_nosync(ourport->rx_irq);
break;
}
ourport->rx_enabled = 0;
}
if (dma && dma->rx_chan) {
dmaengine_pause(dma->tx_chan);
dma_status = dmaengine_tx_status(dma->rx_chan,
dma->rx_cookie, &state);
if (dma_status == DMA_IN_PROGRESS ||
dma_status == DMA_PAUSED) {
received = dma->rx_bytes_requested - state.residue;
dmaengine_terminate_all(dma->rx_chan);
s3c24xx_uart_copy_rx_to_tty(ourport, t, received);
}
}
}
static inline const struct s3c24xx_uart_info
*s3c24xx_port_to_info(struct uart_port *port)
{
return to_ourport(port)->info;
}
static inline const struct s3c2410_uartcfg
*s3c24xx_port_to_cfg(const struct uart_port *port)
{
const struct s3c24xx_uart_port *ourport;
if (port->dev == NULL)
return NULL;
ourport = container_of(port, struct s3c24xx_uart_port, port);
return ourport->cfg;
}
static int s3c24xx_serial_rx_fifocnt(const struct s3c24xx_uart_port *ourport,
unsigned long ufstat)
{
const struct s3c24xx_uart_info *info = ourport->info;
if (ufstat & info->rx_fifofull)
return ourport->port.fifosize;
return (ufstat & info->rx_fifomask) >> info->rx_fifoshift;
}
static void s3c64xx_start_rx_dma(struct s3c24xx_uart_port *ourport);
static void s3c24xx_serial_rx_dma_complete(void *args)
{
struct s3c24xx_uart_port *ourport = args;
struct uart_port *port = &ourport->port;
struct s3c24xx_uart_dma *dma = ourport->dma;
struct tty_port *t = &port->state->port;
struct tty_struct *tty = tty_port_tty_get(&ourport->port.state->port);
struct dma_tx_state state;
unsigned long flags;
int received;
dmaengine_tx_status(dma->rx_chan, dma->rx_cookie, &state);
received = dma->rx_bytes_requested - state.residue;
async_tx_ack(dma->rx_desc);
spin_lock_irqsave(&port->lock, flags);
if (received)
s3c24xx_uart_copy_rx_to_tty(ourport, t, received);
if (tty) {
tty_flip_buffer_push(t);
tty_kref_put(tty);
}
s3c64xx_start_rx_dma(ourport);
spin_unlock_irqrestore(&port->lock, flags);
}
static void s3c64xx_start_rx_dma(struct s3c24xx_uart_port *ourport)
{
struct s3c24xx_uart_dma *dma = ourport->dma;
dma_sync_single_for_device(dma->rx_chan->device->dev, dma->rx_addr,
dma->rx_size, DMA_FROM_DEVICE);
dma->rx_desc = dmaengine_prep_slave_single(dma->rx_chan,
dma->rx_addr, dma->rx_size, DMA_DEV_TO_MEM,
DMA_PREP_INTERRUPT);
if (!dma->rx_desc) {
dev_err(ourport->port.dev, "Unable to get desc for Rx\n");
return;
}
dma->rx_desc->callback = s3c24xx_serial_rx_dma_complete;
dma->rx_desc->callback_param = ourport;
dma->rx_bytes_requested = dma->rx_size;
dma->rx_cookie = dmaengine_submit(dma->rx_desc);
dma_async_issue_pending(dma->rx_chan);
}
/* ? - where has parity gone?? */
#define S3C2410_UERSTAT_PARITY (0x1000)
static void enable_rx_dma(struct s3c24xx_uart_port *ourport)
{
struct uart_port *port = &ourport->port;
unsigned int ucon;
/* set Rx mode to DMA mode */
ucon = rd_regl(port, S3C2410_UCON);
ucon &= ~(S3C64XX_UCON_RXBURST_MASK |
S3C64XX_UCON_TIMEOUT_MASK |
S3C64XX_UCON_EMPTYINT_EN |
S3C64XX_UCON_DMASUS_EN |
S3C64XX_UCON_TIMEOUT_EN |
S3C64XX_UCON_RXMODE_MASK);
ucon |= S3C64XX_UCON_RXBURST_1 |
0xf << S3C64XX_UCON_TIMEOUT_SHIFT |
S3C64XX_UCON_EMPTYINT_EN |
S3C64XX_UCON_TIMEOUT_EN |
S3C64XX_UCON_RXMODE_DMA;
wr_regl(port, S3C2410_UCON, ucon);
ourport->rx_mode = S3C24XX_RX_DMA;
}
static void enable_rx_pio(struct s3c24xx_uart_port *ourport)
{
struct uart_port *port = &ourport->port;
unsigned int ucon;
/* set Rx mode to DMA mode */
ucon = rd_regl(port, S3C2410_UCON);
ucon &= ~S3C64XX_UCON_RXMODE_MASK;
ucon |= S3C64XX_UCON_RXMODE_CPU;
/* Apple types use these bits for IRQ masks */
if (ourport->info->type != TYPE_APPLE_S5L) {
ucon &= ~(S3C64XX_UCON_TIMEOUT_MASK |
S3C64XX_UCON_EMPTYINT_EN |
S3C64XX_UCON_DMASUS_EN |
S3C64XX_UCON_TIMEOUT_EN);
ucon |= 0xf << S3C64XX_UCON_TIMEOUT_SHIFT |
S3C64XX_UCON_TIMEOUT_EN;
}
wr_regl(port, S3C2410_UCON, ucon);
ourport->rx_mode = S3C24XX_RX_PIO;
}
static void s3c24xx_serial_rx_drain_fifo(struct s3c24xx_uart_port *ourport);
static irqreturn_t s3c24xx_serial_rx_chars_dma(void *dev_id)
{
unsigned int utrstat, received;
struct s3c24xx_uart_port *ourport = dev_id;
struct uart_port *port = &ourport->port;
struct s3c24xx_uart_dma *dma = ourport->dma;
struct tty_struct *tty = tty_port_tty_get(&ourport->port.state->port);
struct tty_port *t = &port->state->port;
struct dma_tx_state state;
utrstat = rd_regl(port, S3C2410_UTRSTAT);
rd_regl(port, S3C2410_UFSTAT);
spin_lock(&port->lock);
if (!(utrstat & S3C2410_UTRSTAT_TIMEOUT)) {
s3c64xx_start_rx_dma(ourport);
if (ourport->rx_mode == S3C24XX_RX_PIO)
enable_rx_dma(ourport);
goto finish;
}
if (ourport->rx_mode == S3C24XX_RX_DMA) {
dmaengine_pause(dma->rx_chan);
dmaengine_tx_status(dma->rx_chan, dma->rx_cookie, &state);
dmaengine_terminate_all(dma->rx_chan);
received = dma->rx_bytes_requested - state.residue;
s3c24xx_uart_copy_rx_to_tty(ourport, t, received);
enable_rx_pio(ourport);
}
s3c24xx_serial_rx_drain_fifo(ourport);
if (tty) {
tty_flip_buffer_push(t);
tty_kref_put(tty);
}
wr_regl(port, S3C2410_UTRSTAT, S3C2410_UTRSTAT_TIMEOUT);
finish:
spin_unlock(&port->lock);
return IRQ_HANDLED;
}
static void s3c24xx_serial_rx_drain_fifo(struct s3c24xx_uart_port *ourport)
{
struct uart_port *port = &ourport->port;
unsigned int ufcon, ch, flag, ufstat, uerstat;
unsigned int fifocnt = 0;
int max_count = port->fifosize;
while (max_count-- > 0) {
/*
* Receive all characters known to be in FIFO
* before reading FIFO level again
*/
if (fifocnt == 0) {
ufstat = rd_regl(port, S3C2410_UFSTAT);
fifocnt = s3c24xx_serial_rx_fifocnt(ourport, ufstat);
if (fifocnt == 0)
break;
}
fifocnt--;
uerstat = rd_regl(port, S3C2410_UERSTAT);
ch = rd_reg(port, S3C2410_URXH);
if (port->flags & UPF_CONS_FLOW) {
int txe = s3c24xx_serial_txempty_nofifo(port);
if (ourport->rx_enabled) {
if (!txe) {
ourport->rx_enabled = 0;
continue;
}
} else {
if (txe) {
ufcon = rd_regl(port, S3C2410_UFCON);
ufcon |= S3C2410_UFCON_RESETRX;
wr_regl(port, S3C2410_UFCON, ufcon);
ourport->rx_enabled = 1;
return;
}
continue;
}
}
/* insert the character into the buffer */
flag = TTY_NORMAL;
port->icount.rx++;
if (unlikely(uerstat & S3C2410_UERSTAT_ANY)) {
dev_dbg(port->dev,
"rxerr: port ch=0x%02x, rxs=0x%08x\n",
ch, uerstat);
/* check for break */
if (uerstat & S3C2410_UERSTAT_BREAK) {
dev_dbg(port->dev, "break!\n");
port->icount.brk++;
if (uart_handle_break(port))
continue; /* Ignore character */
}
if (uerstat & S3C2410_UERSTAT_FRAME)
port->icount.frame++;
if (uerstat & S3C2410_UERSTAT_OVERRUN)
port->icount.overrun++;
uerstat &= port->read_status_mask;
if (uerstat & S3C2410_UERSTAT_BREAK)
flag = TTY_BREAK;
else if (uerstat & S3C2410_UERSTAT_PARITY)
flag = TTY_PARITY;
else if (uerstat & (S3C2410_UERSTAT_FRAME |
S3C2410_UERSTAT_OVERRUN))
flag = TTY_FRAME;
}
if (uart_handle_sysrq_char(port, ch))
continue; /* Ignore character */
uart_insert_char(port, uerstat, S3C2410_UERSTAT_OVERRUN,
ch, flag);
}
tty_flip_buffer_push(&port->state->port);
}
static irqreturn_t s3c24xx_serial_rx_chars_pio(void *dev_id)
{
struct s3c24xx_uart_port *ourport = dev_id;
struct uart_port *port = &ourport->port;
spin_lock(&port->lock);
s3c24xx_serial_rx_drain_fifo(ourport);
spin_unlock(&port->lock);
return IRQ_HANDLED;
}
static irqreturn_t s3c24xx_serial_rx_irq(int irq, void *dev_id)
{
struct s3c24xx_uart_port *ourport = dev_id;
if (ourport->dma && ourport->dma->rx_chan)
return s3c24xx_serial_rx_chars_dma(dev_id);
return s3c24xx_serial_rx_chars_pio(dev_id);
}
static void s3c24xx_serial_tx_chars(struct s3c24xx_uart_port *ourport)
{
struct uart_port *port = &ourport->port;
struct circ_buf *xmit = &port->state->xmit;
int count, dma_count = 0;
count = CIRC_CNT_TO_END(xmit->head, xmit->tail, UART_XMIT_SIZE);
if (ourport->dma && ourport->dma->tx_chan &&
count >= ourport->min_dma_size) {
int align = dma_get_cache_alignment() -
(xmit->tail & (dma_get_cache_alignment() - 1));
if (count - align >= ourport->min_dma_size) {
dma_count = count - align;
count = align;
}
}
if (port->x_char) {
wr_reg(port, S3C2410_UTXH, port->x_char);
port->icount.tx++;
port->x_char = 0;
return;
}
/* if there isn't anything more to transmit, or the uart is now
* stopped, disable the uart and exit
*/
if (uart_circ_empty(xmit) || uart_tx_stopped(port)) {
s3c24xx_serial_stop_tx(port);
return;
}
/* try and drain the buffer... */
if (count > port->fifosize) {
count = port->fifosize;
dma_count = 0;
}
while (!uart_circ_empty(xmit) && count > 0) {
if (rd_regl(port, S3C2410_UFSTAT) & ourport->info->tx_fifofull)
break;
wr_reg(port, S3C2410_UTXH, xmit->buf[xmit->tail]);
uart_xmit_advance(port, 1);
count--;
}
if (!count && dma_count) {
s3c24xx_serial_start_tx_dma(ourport, dma_count);
return;
}
if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
uart_write_wakeup(port);
if (uart_circ_empty(xmit))
s3c24xx_serial_stop_tx(port);
}
static irqreturn_t s3c24xx_serial_tx_irq(int irq, void *id)
{
struct s3c24xx_uart_port *ourport = id;
struct uart_port *port = &ourport->port;
spin_lock(&port->lock);
s3c24xx_serial_tx_chars(ourport);
spin_unlock(&port->lock);
return IRQ_HANDLED;
}
/* interrupt handler for s3c64xx and later SoC's.*/
static irqreturn_t s3c64xx_serial_handle_irq(int irq, void *id)
{
const struct s3c24xx_uart_port *ourport = id;
const struct uart_port *port = &ourport->port;
unsigned int pend = rd_regl(port, S3C64XX_UINTP);
irqreturn_t ret = IRQ_HANDLED;
if (pend & S3C64XX_UINTM_RXD_MSK) {
ret = s3c24xx_serial_rx_irq(irq, id);
wr_regl(port, S3C64XX_UINTP, S3C64XX_UINTM_RXD_MSK);
}
if (pend & S3C64XX_UINTM_TXD_MSK) {
ret = s3c24xx_serial_tx_irq(irq, id);
wr_regl(port, S3C64XX_UINTP, S3C64XX_UINTM_TXD_MSK);
}
return ret;
}
/* interrupt handler for Apple SoC's.*/
static irqreturn_t apple_serial_handle_irq(int irq, void *id)
{
const struct s3c24xx_uart_port *ourport = id;
const struct uart_port *port = &ourport->port;
unsigned int pend = rd_regl(port, S3C2410_UTRSTAT);
irqreturn_t ret = IRQ_NONE;
if (pend & (APPLE_S5L_UTRSTAT_RXTHRESH | APPLE_S5L_UTRSTAT_RXTO)) {
wr_regl(port, S3C2410_UTRSTAT,
APPLE_S5L_UTRSTAT_RXTHRESH | APPLE_S5L_UTRSTAT_RXTO);
ret = s3c24xx_serial_rx_irq(irq, id);
}
if (pend & APPLE_S5L_UTRSTAT_TXTHRESH) {
wr_regl(port, S3C2410_UTRSTAT, APPLE_S5L_UTRSTAT_TXTHRESH);
ret = s3c24xx_serial_tx_irq(irq, id);
}
return ret;
}
static unsigned int s3c24xx_serial_tx_empty(struct uart_port *port)
{
const struct s3c24xx_uart_info *info = s3c24xx_port_to_info(port);
unsigned long ufstat = rd_regl(port, S3C2410_UFSTAT);
unsigned long ufcon = rd_regl(port, S3C2410_UFCON);
if (ufcon & S3C2410_UFCON_FIFOMODE) {
if ((ufstat & info->tx_fifomask) != 0 ||
(ufstat & info->tx_fifofull))
return 0;
return 1;
}
return s3c24xx_serial_txempty_nofifo(port);
}
/* no modem control lines */
static unsigned int s3c24xx_serial_get_mctrl(struct uart_port *port)
{
unsigned int umstat = rd_reg(port, S3C2410_UMSTAT);
if (umstat & S3C2410_UMSTAT_CTS)
return TIOCM_CAR | TIOCM_DSR | TIOCM_CTS;
else
return TIOCM_CAR | TIOCM_DSR;
}
static void s3c24xx_serial_set_mctrl(struct uart_port *port, unsigned int mctrl)
{
unsigned int umcon = rd_regl(port, S3C2410_UMCON);
unsigned int ucon = rd_regl(port, S3C2410_UCON);
if (mctrl & TIOCM_RTS)
umcon |= S3C2410_UMCOM_RTS_LOW;
else
umcon &= ~S3C2410_UMCOM_RTS_LOW;
wr_regl(port, S3C2410_UMCON, umcon);
if (mctrl & TIOCM_LOOP)
ucon |= S3C2410_UCON_LOOPBACK;
else
ucon &= ~S3C2410_UCON_LOOPBACK;
wr_regl(port, S3C2410_UCON, ucon);
}
static void s3c24xx_serial_break_ctl(struct uart_port *port, int break_state)
{
unsigned long flags;
unsigned int ucon;
spin_lock_irqsave(&port->lock, flags);
ucon = rd_regl(port, S3C2410_UCON);
if (break_state)
ucon |= S3C2410_UCON_SBREAK;
else
ucon &= ~S3C2410_UCON_SBREAK;
wr_regl(port, S3C2410_UCON, ucon);
spin_unlock_irqrestore(&port->lock, flags);
}
static int s3c24xx_serial_request_dma(struct s3c24xx_uart_port *p)
{
struct s3c24xx_uart_dma *dma = p->dma;
struct dma_slave_caps dma_caps;
const char *reason = NULL;
int ret;
/* Default slave configuration parameters */
dma->rx_conf.direction = DMA_DEV_TO_MEM;
dma->rx_conf.src_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
dma->rx_conf.src_addr = p->port.mapbase + S3C2410_URXH;
dma->rx_conf.src_maxburst = 1;
dma->tx_conf.direction = DMA_MEM_TO_DEV;
dma->tx_conf.dst_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
dma->tx_conf.dst_addr = p->port.mapbase + S3C2410_UTXH;
dma->tx_conf.dst_maxburst = 1;
dma->rx_chan = dma_request_chan(p->port.dev, "rx");
if (IS_ERR(dma->rx_chan)) {
reason = "DMA RX channel request failed";
ret = PTR_ERR(dma->rx_chan);
goto err_warn;
}
ret = dma_get_slave_caps(dma->rx_chan, &dma_caps);
if (ret < 0 ||
dma_caps.residue_granularity < DMA_RESIDUE_GRANULARITY_BURST) {
reason = "insufficient DMA RX engine capabilities";
ret = -EOPNOTSUPP;
goto err_release_rx;
}
dmaengine_slave_config(dma->rx_chan, &dma->rx_conf);
dma->tx_chan = dma_request_chan(p->port.dev, "tx");
if (IS_ERR(dma->tx_chan)) {
reason = "DMA TX channel request failed";
ret = PTR_ERR(dma->tx_chan);
goto err_release_rx;
}
ret = dma_get_slave_caps(dma->tx_chan, &dma_caps);
if (ret < 0 ||
dma_caps.residue_granularity < DMA_RESIDUE_GRANULARITY_BURST) {
reason = "insufficient DMA TX engine capabilities";
ret = -EOPNOTSUPP;
goto err_release_tx;
}
dmaengine_slave_config(dma->tx_chan, &dma->tx_conf);
/* RX buffer */
dma->rx_size = PAGE_SIZE;
dma->rx_buf = kmalloc(dma->rx_size, GFP_KERNEL);
if (!dma->rx_buf) {
ret = -ENOMEM;
goto err_release_tx;
}
dma->rx_addr = dma_map_single(dma->rx_chan->device->dev, dma->rx_buf,
dma->rx_size, DMA_FROM_DEVICE);
if (dma_mapping_error(dma->rx_chan->device->dev, dma->rx_addr)) {
reason = "DMA mapping error for RX buffer";
ret = -EIO;
goto err_free_rx;
}
/* TX buffer */
dma->tx_addr = dma_map_single(dma->tx_chan->device->dev,
p->port.state->xmit.buf, UART_XMIT_SIZE,
DMA_TO_DEVICE);
if (dma_mapping_error(dma->tx_chan->device->dev, dma->tx_addr)) {
reason = "DMA mapping error for TX buffer";
ret = -EIO;
goto err_unmap_rx;
}
return 0;
err_unmap_rx:
dma_unmap_single(dma->rx_chan->device->dev, dma->rx_addr,
dma->rx_size, DMA_FROM_DEVICE);
err_free_rx:
kfree(dma->rx_buf);
err_release_tx:
dma_release_channel(dma->tx_chan);
err_release_rx:
dma_release_channel(dma->rx_chan);
err_warn:
if (reason)
dev_warn(p->port.dev, "%s, DMA will not be used\n", reason);
return ret;
}
static void s3c24xx_serial_release_dma(struct s3c24xx_uart_port *p)
{
struct s3c24xx_uart_dma *dma = p->dma;
if (dma->rx_chan) {
dmaengine_terminate_all(dma->rx_chan);
dma_unmap_single(dma->rx_chan->device->dev, dma->rx_addr,
dma->rx_size, DMA_FROM_DEVICE);
kfree(dma->rx_buf);
dma_release_channel(dma->rx_chan);
dma->rx_chan = NULL;
}
if (dma->tx_chan) {
dmaengine_terminate_all(dma->tx_chan);
dma_unmap_single(dma->tx_chan->device->dev, dma->tx_addr,
UART_XMIT_SIZE, DMA_TO_DEVICE);
dma_release_channel(dma->tx_chan);
dma->tx_chan = NULL;
}
}
static void s3c24xx_serial_shutdown(struct uart_port *port)
{
struct s3c24xx_uart_port *ourport = to_ourport(port);
if (ourport->tx_claimed) {
free_irq(ourport->tx_irq, ourport);
ourport->tx_enabled = 0;
ourport->tx_claimed = 0;
ourport->tx_mode = 0;
}
if (ourport->rx_claimed) {
free_irq(ourport->rx_irq, ourport);
ourport->rx_claimed = 0;
ourport->rx_enabled = 0;
}
if (ourport->dma)
s3c24xx_serial_release_dma(ourport);
ourport->tx_in_progress = 0;
}
static void s3c64xx_serial_shutdown(struct uart_port *port)
{
struct s3c24xx_uart_port *ourport = to_ourport(port);
ourport->tx_enabled = 0;
ourport->tx_mode = 0;
ourport->rx_enabled = 0;
free_irq(port->irq, ourport);
wr_regl(port, S3C64XX_UINTP, 0xf);
wr_regl(port, S3C64XX_UINTM, 0xf);
if (ourport->dma)
s3c24xx_serial_release_dma(ourport);
ourport->tx_in_progress = 0;
}
static void apple_s5l_serial_shutdown(struct uart_port *port)
{
struct s3c24xx_uart_port *ourport = to_ourport(port);
unsigned int ucon;
ucon = rd_regl(port, S3C2410_UCON);
ucon &= ~(APPLE_S5L_UCON_TXTHRESH_ENA_MSK |
APPLE_S5L_UCON_RXTHRESH_ENA_MSK |
APPLE_S5L_UCON_RXTO_ENA_MSK);
wr_regl(port, S3C2410_UCON, ucon);
wr_regl(port, S3C2410_UTRSTAT, APPLE_S5L_UTRSTAT_ALL_FLAGS);
free_irq(port->irq, ourport);
ourport->tx_enabled = 0;
ourport->tx_mode = 0;
ourport->rx_enabled = 0;
if (ourport->dma)
s3c24xx_serial_release_dma(ourport);
ourport->tx_in_progress = 0;
}
static int s3c24xx_serial_startup(struct uart_port *port)
{
struct s3c24xx_uart_port *ourport = to_ourport(port);
int ret;
ourport->rx_enabled = 1;
ret = request_irq(ourport->rx_irq, s3c24xx_serial_rx_irq, 0,
s3c24xx_serial_portname(port), ourport);
if (ret != 0) {
dev_err(port->dev, "cannot get irq %d\n", ourport->rx_irq);
return ret;
}
ourport->rx_claimed = 1;
dev_dbg(port->dev, "requesting tx irq...\n");
ourport->tx_enabled = 1;
ret = request_irq(ourport->tx_irq, s3c24xx_serial_tx_irq, 0,
s3c24xx_serial_portname(port), ourport);
if (ret) {
dev_err(port->dev, "cannot get irq %d\n", ourport->tx_irq);
goto err;
}
ourport->tx_claimed = 1;
/* the port reset code should have done the correct
* register setup for the port controls
*/
return ret;
err:
s3c24xx_serial_shutdown(port);
return ret;
}
static int s3c64xx_serial_startup(struct uart_port *port)
{
struct s3c24xx_uart_port *ourport = to_ourport(port);
unsigned long flags;
unsigned int ufcon;
int ret;
wr_regl(port, S3C64XX_UINTM, 0xf);
if (ourport->dma) {
ret = s3c24xx_serial_request_dma(ourport);
if (ret < 0) {
devm_kfree(port->dev, ourport->dma);
ourport->dma = NULL;
}
}
ret = request_irq(port->irq, s3c64xx_serial_handle_irq, IRQF_SHARED,
s3c24xx_serial_portname(port), ourport);
if (ret) {
dev_err(port->dev, "cannot get irq %d\n", port->irq);
return ret;
}
/* For compatibility with s3c24xx Soc's */
ourport->rx_enabled = 1;
ourport->tx_enabled = 0;
spin_lock_irqsave(&port->lock, flags);
ufcon = rd_regl(port, S3C2410_UFCON);
ufcon |= S3C2410_UFCON_RESETRX | S5PV210_UFCON_RXTRIG8;
if (!uart_console(port))
ufcon |= S3C2410_UFCON_RESETTX;
wr_regl(port, S3C2410_UFCON, ufcon);
enable_rx_pio(ourport);
spin_unlock_irqrestore(&port->lock, flags);
/* Enable Rx Interrupt */
s3c24xx_clear_bit(port, S3C64XX_UINTM_RXD, S3C64XX_UINTM);
return ret;
}
static int apple_s5l_serial_startup(struct uart_port *port)
{
struct s3c24xx_uart_port *ourport = to_ourport(port);
unsigned long flags;
unsigned int ufcon;
int ret;
wr_regl(port, S3C2410_UTRSTAT, APPLE_S5L_UTRSTAT_ALL_FLAGS);
ret = request_irq(port->irq, apple_serial_handle_irq, 0,
s3c24xx_serial_portname(port), ourport);
if (ret) {
dev_err(port->dev, "cannot get irq %d\n", port->irq);
return ret;
}
/* For compatibility with s3c24xx Soc's */
ourport->rx_enabled = 1;
ourport->tx_enabled = 0;
spin_lock_irqsave(&port->lock, flags);
ufcon = rd_regl(port, S3C2410_UFCON);
ufcon |= S3C2410_UFCON_RESETRX | S5PV210_UFCON_RXTRIG8;
if (!uart_console(port))
ufcon |= S3C2410_UFCON_RESETTX;
wr_regl(port, S3C2410_UFCON, ufcon);
enable_rx_pio(ourport);
spin_unlock_irqrestore(&port->lock, flags);
/* Enable Rx Interrupt */
s3c24xx_set_bit(port, APPLE_S5L_UCON_RXTHRESH_ENA, S3C2410_UCON);
s3c24xx_set_bit(port, APPLE_S5L_UCON_RXTO_ENA, S3C2410_UCON);
return ret;
}
/* power power management control */
static void s3c24xx_serial_pm(struct uart_port *port, unsigned int level,
unsigned int old)
{
struct s3c24xx_uart_port *ourport = to_ourport(port);
int timeout = 10000;
ourport->pm_level = level;
switch (level) {
case 3:
while (--timeout && !s3c24xx_serial_txempty_nofifo(port))
udelay(100);
if (!IS_ERR(ourport->baudclk))
clk_disable_unprepare(ourport->baudclk);
clk_disable_unprepare(ourport->clk);
break;
case 0:
clk_prepare_enable(ourport->clk);
if (!IS_ERR(ourport->baudclk))
clk_prepare_enable(ourport->baudclk);
break;
default:
dev_err(port->dev, "s3c24xx_serial: unknown pm %d\n", level);
}
}
/* baud rate calculation
*
* The UARTs on the S3C2410/S3C2440 can take their clocks from a number
* of different sources, including the peripheral clock ("pclk") and an
* external clock ("uclk"). The S3C2440 also adds the core clock ("fclk")
* with a programmable extra divisor.
*
* The following code goes through the clock sources, and calculates the
* baud clocks (and the resultant actual baud rates) and then tries to
* pick the closest one and select that.
*
*/
#define MAX_CLK_NAME_LENGTH 15
static inline int s3c24xx_serial_getsource(struct uart_port *port)
{
const struct s3c24xx_uart_info *info = s3c24xx_port_to_info(port);
unsigned int ucon;
if (info->num_clks == 1)
return 0;
ucon = rd_regl(port, S3C2410_UCON);
ucon &= info->clksel_mask;
return ucon >> info->clksel_shift;
}
static void s3c24xx_serial_setsource(struct uart_port *port,
unsigned int clk_sel)
{
const struct s3c24xx_uart_info *info = s3c24xx_port_to_info(port);
unsigned int ucon;
if (info->num_clks == 1)
return;
ucon = rd_regl(port, S3C2410_UCON);
if ((ucon & info->clksel_mask) >> info->clksel_shift == clk_sel)
return;
ucon &= ~info->clksel_mask;
ucon |= clk_sel << info->clksel_shift;
wr_regl(port, S3C2410_UCON, ucon);
}
static unsigned int s3c24xx_serial_getclk(struct s3c24xx_uart_port *ourport,
unsigned int req_baud, struct clk **best_clk,
unsigned int *clk_num)
{
const struct s3c24xx_uart_info *info = ourport->info;
struct clk *clk;
unsigned long rate;
unsigned int cnt, baud, quot, best_quot = 0;
char clkname[MAX_CLK_NAME_LENGTH];
int calc_deviation, deviation = (1 << 30) - 1;
for (cnt = 0; cnt < info->num_clks; cnt++) {
/* Keep selected clock if provided */
if (ourport->cfg->clk_sel &&
!(ourport->cfg->clk_sel & (1 << cnt)))
continue;
sprintf(clkname, "clk_uart_baud%d", cnt);
clk = clk_get(ourport->port.dev, clkname);
if (IS_ERR(clk))
continue;
rate = clk_get_rate(clk);
if (!rate) {
dev_err(ourport->port.dev,
"Failed to get clock rate for %s.\n", clkname);
clk_put(clk);
continue;
}
if (ourport->info->has_divslot) {
unsigned long div = rate / req_baud;
/* The UDIVSLOT register on the newer UARTs allows us to
* get a divisor adjustment of 1/16th on the baud clock.
*
* We don't keep the UDIVSLOT value (the 16ths we
* calculated by not multiplying the baud by 16) as it
* is easy enough to recalculate.
*/
quot = div / 16;
baud = rate / div;
} else {
quot = (rate + (8 * req_baud)) / (16 * req_baud);
baud = rate / (quot * 16);
}
quot--;
calc_deviation = abs(req_baud - baud);
if (calc_deviation < deviation) {
/*
* If we find a better clk, release the previous one, if
* any.
*/
if (!IS_ERR(*best_clk))
clk_put(*best_clk);
*best_clk = clk;
best_quot = quot;
*clk_num = cnt;
deviation = calc_deviation;
} else {
clk_put(clk);
}
}
return best_quot;
}
/* udivslot_table[]
*
* This table takes the fractional value of the baud divisor and gives
* the recommended setting for the UDIVSLOT register.
*/
static const u16 udivslot_table[16] = {
[0] = 0x0000,
[1] = 0x0080,
[2] = 0x0808,
[3] = 0x0888,
[4] = 0x2222,
[5] = 0x4924,
[6] = 0x4A52,
[7] = 0x54AA,
[8] = 0x5555,
[9] = 0xD555,
[10] = 0xD5D5,
[11] = 0xDDD5,
[12] = 0xDDDD,
[13] = 0xDFDD,
[14] = 0xDFDF,
[15] = 0xFFDF,
};
static void s3c24xx_serial_set_termios(struct uart_port *port,
struct ktermios *termios,
const struct ktermios *old)
{
const struct s3c2410_uartcfg *cfg = s3c24xx_port_to_cfg(port);
struct s3c24xx_uart_port *ourport = to_ourport(port);
struct clk *clk = ERR_PTR(-EINVAL);
unsigned long flags;
unsigned int baud, quot, clk_sel = 0;
unsigned int ulcon;
unsigned int umcon;
unsigned int udivslot = 0;
/*
* We don't support modem control lines.
*/
termios->c_cflag &= ~(HUPCL | CMSPAR);
termios->c_cflag |= CLOCAL;
/*
* Ask the core to calculate the divisor for us.
*/
baud = uart_get_baud_rate(port, termios, old, 0, 3000000);
quot = s3c24xx_serial_getclk(ourport, baud, &clk, &clk_sel);
if (baud == 38400 && (port->flags & UPF_SPD_MASK) == UPF_SPD_CUST)
quot = port->custom_divisor;
if (IS_ERR(clk))
return;
/* check to see if we need to change clock source */
if (ourport->baudclk != clk) {
clk_prepare_enable(clk);
s3c24xx_serial_setsource(port, clk_sel);
if (!IS_ERR(ourport->baudclk)) {
clk_disable_unprepare(ourport->baudclk);
ourport->baudclk = ERR_PTR(-EINVAL);
}
ourport->baudclk = clk;
ourport->baudclk_rate = clk ? clk_get_rate(clk) : 0;
}
if (ourport->info->has_divslot) {
unsigned int div = ourport->baudclk_rate / baud;
if (cfg->has_fracval) {
udivslot = (div & 15);
dev_dbg(port->dev, "fracval = %04x\n", udivslot);
} else {
udivslot = udivslot_table[div & 15];
dev_dbg(port->dev, "udivslot = %04x (div %d)\n",
udivslot, div & 15);
}
}
switch (termios->c_cflag & CSIZE) {
case CS5:
dev_dbg(port->dev, "config: 5bits/char\n");
ulcon = S3C2410_LCON_CS5;
break;
case CS6:
dev_dbg(port->dev, "config: 6bits/char\n");
ulcon = S3C2410_LCON_CS6;
break;
case CS7:
dev_dbg(port->dev, "config: 7bits/char\n");
ulcon = S3C2410_LCON_CS7;
break;
case CS8:
default:
dev_dbg(port->dev, "config: 8bits/char\n");
ulcon = S3C2410_LCON_CS8;
break;
}
/* preserve original lcon IR settings */
ulcon |= (cfg->ulcon & S3C2410_LCON_IRM);
if (termios->c_cflag & CSTOPB)
ulcon |= S3C2410_LCON_STOPB;
if (termios->c_cflag & PARENB) {
if (termios->c_cflag & PARODD)
ulcon |= S3C2410_LCON_PODD;
else
ulcon |= S3C2410_LCON_PEVEN;
} else {
ulcon |= S3C2410_LCON_PNONE;
}
spin_lock_irqsave(&port->lock, flags);
dev_dbg(port->dev,
"setting ulcon to %08x, brddiv to %d, udivslot %08x\n",
ulcon, quot, udivslot);
wr_regl(port, S3C2410_ULCON, ulcon);
wr_regl(port, S3C2410_UBRDIV, quot);
port->status &= ~UPSTAT_AUTOCTS;
umcon = rd_regl(port, S3C2410_UMCON);
if (termios->c_cflag & CRTSCTS) {
umcon |= S3C2410_UMCOM_AFC;
/* Disable RTS when RX FIFO contains 63 bytes */
umcon &= ~S3C2412_UMCON_AFC_8;
port->status = UPSTAT_AUTOCTS;
} else {
umcon &= ~S3C2410_UMCOM_AFC;
}
wr_regl(port, S3C2410_UMCON, umcon);
if (ourport->info->has_divslot)
wr_regl(port, S3C2443_DIVSLOT, udivslot);
dev_dbg(port->dev,
"uart: ulcon = 0x%08x, ucon = 0x%08x, ufcon = 0x%08x\n",
rd_regl(port, S3C2410_ULCON),
rd_regl(port, S3C2410_UCON),
rd_regl(port, S3C2410_UFCON));
/*
* Update the per-port timeout.
*/
uart_update_timeout(port, termios->c_cflag, baud);
/*
* Which character status flags are we interested in?
*/
port->read_status_mask = S3C2410_UERSTAT_OVERRUN;
if (termios->c_iflag & INPCK)
port->read_status_mask |= S3C2410_UERSTAT_FRAME |
S3C2410_UERSTAT_PARITY;
/*
* Which character status flags should we ignore?
*/
port->ignore_status_mask = 0;
if (termios->c_iflag & IGNPAR)
port->ignore_status_mask |= S3C2410_UERSTAT_OVERRUN;
if (termios->c_iflag & IGNBRK && termios->c_iflag & IGNPAR)
port->ignore_status_mask |= S3C2410_UERSTAT_FRAME;
/*
* Ignore all characters if CREAD is not set.
*/
if ((termios->c_cflag & CREAD) == 0)
port->ignore_status_mask |= RXSTAT_DUMMY_READ;
spin_unlock_irqrestore(&port->lock, flags);
}
static const char *s3c24xx_serial_type(struct uart_port *port)
{
const struct s3c24xx_uart_port *ourport = to_ourport(port);
switch (ourport->info->type) {
case TYPE_S3C24XX:
return "S3C24XX";
case TYPE_S3C6400:
return "S3C6400/10";
case TYPE_APPLE_S5L:
return "APPLE S5L";
default:
return NULL;
}
}
static void s3c24xx_serial_config_port(struct uart_port *port, int flags)
{
const struct s3c24xx_uart_info *info = s3c24xx_port_to_info(port);
if (flags & UART_CONFIG_TYPE)
port->type = info->port_type;
}
/*
* verify the new serial_struct (for TIOCSSERIAL).
*/
static int
s3c24xx_serial_verify_port(struct uart_port *port, struct serial_struct *ser)
{
const struct s3c24xx_uart_info *info = s3c24xx_port_to_info(port);
if (ser->type != PORT_UNKNOWN && ser->type != info->port_type)
return -EINVAL;
return 0;
}
#ifdef CONFIG_SERIAL_SAMSUNG_CONSOLE
static struct console s3c24xx_serial_console;
static void __init s3c24xx_serial_register_console(void)
{
register_console(&s3c24xx_serial_console);
}
static void s3c24xx_serial_unregister_console(void)
{
if (console_is_registered(&s3c24xx_serial_console))
unregister_console(&s3c24xx_serial_console);
}
#define S3C24XX_SERIAL_CONSOLE &s3c24xx_serial_console
#else
static inline void s3c24xx_serial_register_console(void) { }
static inline void s3c24xx_serial_unregister_console(void) { }
#define S3C24XX_SERIAL_CONSOLE NULL
#endif
#if defined(CONFIG_SERIAL_SAMSUNG_CONSOLE) && defined(CONFIG_CONSOLE_POLL)
static int s3c24xx_serial_get_poll_char(struct uart_port *port);
static void s3c24xx_serial_put_poll_char(struct uart_port *port,
unsigned char c);
#endif
static const struct uart_ops s3c24xx_serial_ops = {
.pm = s3c24xx_serial_pm,
.tx_empty = s3c24xx_serial_tx_empty,
.get_mctrl = s3c24xx_serial_get_mctrl,
.set_mctrl = s3c24xx_serial_set_mctrl,
.stop_tx = s3c24xx_serial_stop_tx,
.start_tx = s3c24xx_serial_start_tx,
.stop_rx = s3c24xx_serial_stop_rx,
.break_ctl = s3c24xx_serial_break_ctl,
.startup = s3c24xx_serial_startup,
.shutdown = s3c24xx_serial_shutdown,
.set_termios = s3c24xx_serial_set_termios,
.type = s3c24xx_serial_type,
.config_port = s3c24xx_serial_config_port,
.verify_port = s3c24xx_serial_verify_port,
#if defined(CONFIG_SERIAL_SAMSUNG_CONSOLE) && defined(CONFIG_CONSOLE_POLL)
.poll_get_char = s3c24xx_serial_get_poll_char,
.poll_put_char = s3c24xx_serial_put_poll_char,
#endif
};
static const struct uart_ops s3c64xx_serial_ops = {
.pm = s3c24xx_serial_pm,
.tx_empty = s3c24xx_serial_tx_empty,
.get_mctrl = s3c24xx_serial_get_mctrl,
.set_mctrl = s3c24xx_serial_set_mctrl,
.stop_tx = s3c24xx_serial_stop_tx,
.start_tx = s3c24xx_serial_start_tx,
.stop_rx = s3c24xx_serial_stop_rx,
.break_ctl = s3c24xx_serial_break_ctl,
.startup = s3c64xx_serial_startup,
.shutdown = s3c64xx_serial_shutdown,
.set_termios = s3c24xx_serial_set_termios,
.type = s3c24xx_serial_type,
.config_port = s3c24xx_serial_config_port,
.verify_port = s3c24xx_serial_verify_port,
#if defined(CONFIG_SERIAL_SAMSUNG_CONSOLE) && defined(CONFIG_CONSOLE_POLL)
.poll_get_char = s3c24xx_serial_get_poll_char,
.poll_put_char = s3c24xx_serial_put_poll_char,
#endif
};
static const struct uart_ops apple_s5l_serial_ops = {
.pm = s3c24xx_serial_pm,
.tx_empty = s3c24xx_serial_tx_empty,
.get_mctrl = s3c24xx_serial_get_mctrl,
.set_mctrl = s3c24xx_serial_set_mctrl,
.stop_tx = s3c24xx_serial_stop_tx,
.start_tx = s3c24xx_serial_start_tx,
.stop_rx = s3c24xx_serial_stop_rx,
.break_ctl = s3c24xx_serial_break_ctl,
.startup = apple_s5l_serial_startup,
.shutdown = apple_s5l_serial_shutdown,
.set_termios = s3c24xx_serial_set_termios,
.type = s3c24xx_serial_type,
.config_port = s3c24xx_serial_config_port,
.verify_port = s3c24xx_serial_verify_port,
#if defined(CONFIG_SERIAL_SAMSUNG_CONSOLE) && defined(CONFIG_CONSOLE_POLL)
.poll_get_char = s3c24xx_serial_get_poll_char,
.poll_put_char = s3c24xx_serial_put_poll_char,
#endif
};
static struct uart_driver s3c24xx_uart_drv = {
.owner = THIS_MODULE,
.driver_name = "s3c2410_serial",
.nr = UART_NR,
.cons = S3C24XX_SERIAL_CONSOLE,
.dev_name = S3C24XX_SERIAL_NAME,
.major = S3C24XX_SERIAL_MAJOR,
.minor = S3C24XX_SERIAL_MINOR,
};
static struct s3c24xx_uart_port s3c24xx_serial_ports[UART_NR];
static void s3c24xx_serial_init_port_default(int index) {
struct uart_port *port = &s3c24xx_serial_ports[index].port;
spin_lock_init(&port->lock);
port->iotype = UPIO_MEM;
port->uartclk = 0;
port->fifosize = 16;
port->ops = &s3c24xx_serial_ops;
port->flags = UPF_BOOT_AUTOCONF;
port->line = index;
}
/* s3c24xx_serial_resetport
*
* reset the fifos and other the settings.
*/
static void s3c24xx_serial_resetport(struct uart_port *port,
const struct s3c2410_uartcfg *cfg)
{
const struct s3c24xx_uart_info *info = s3c24xx_port_to_info(port);
unsigned long ucon = rd_regl(port, S3C2410_UCON);
ucon &= (info->clksel_mask | info->ucon_mask);
wr_regl(port, S3C2410_UCON, ucon | cfg->ucon);
/* reset both fifos */
wr_regl(port, S3C2410_UFCON, cfg->ufcon | S3C2410_UFCON_RESETBOTH);
wr_regl(port, S3C2410_UFCON, cfg->ufcon);
/* some delay is required after fifo reset */
udelay(1);
}
static int s3c24xx_serial_enable_baudclk(struct s3c24xx_uart_port *ourport)
{
struct device *dev = ourport->port.dev;
const struct s3c24xx_uart_info *info = ourport->info;
char clk_name[MAX_CLK_NAME_LENGTH];
unsigned int clk_sel;
struct clk *clk;
int clk_num;
int ret;
clk_sel = ourport->cfg->clk_sel ? : info->def_clk_sel;
for (clk_num = 0; clk_num < info->num_clks; clk_num++) {
if (!(clk_sel & (1 << clk_num)))
continue;
sprintf(clk_name, "clk_uart_baud%d", clk_num);
clk = clk_get(dev, clk_name);
if (IS_ERR(clk))
continue;
ret = clk_prepare_enable(clk);
if (ret) {
clk_put(clk);
continue;
}
ourport->baudclk = clk;
ourport->baudclk_rate = clk_get_rate(clk);
s3c24xx_serial_setsource(&ourport->port, clk_num);
return 0;
}
return -EINVAL;
}
/* s3c24xx_serial_init_port
*
* initialise a single serial port from the platform device given
*/
static int s3c24xx_serial_init_port(struct s3c24xx_uart_port *ourport,
struct platform_device *platdev)
{
struct uart_port *port = &ourport->port;
const struct s3c2410_uartcfg *cfg = ourport->cfg;
struct resource *res;
int ret;
if (platdev == NULL)
return -ENODEV;
if (port->mapbase != 0)
return -EINVAL;
/* setup info for port */
port->dev = &platdev->dev;
port->uartclk = 1;
if (cfg->uart_flags & UPF_CONS_FLOW) {
dev_dbg(port->dev, "enabling flow control\n");
port->flags |= UPF_CONS_FLOW;
}
/* sort our the physical and virtual addresses for each UART */
res = platform_get_resource(platdev, IORESOURCE_MEM, 0);
if (res == NULL) {
dev_err(port->dev, "failed to find memory resource for uart\n");
return -EINVAL;
}
dev_dbg(port->dev, "resource %pR)\n", res);
port->membase = devm_ioremap_resource(port->dev, res);
if (IS_ERR(port->membase)) {
dev_err(port->dev, "failed to remap controller address\n");
return -EBUSY;
}
port->mapbase = res->start;
ret = platform_get_irq(platdev, 0);
if (ret < 0) {
port->irq = 0;
} else {
port->irq = ret;
ourport->rx_irq = ret;
ourport->tx_irq = ret + 1;
}
switch (ourport->info->type) {
case TYPE_S3C24XX:
ret = platform_get_irq(platdev, 1);
if (ret > 0)
ourport->tx_irq = ret;
break;
default:
break;
}
/*
* DMA is currently supported only on DT platforms, if DMA properties
* are specified.
*/
if (platdev->dev.of_node && of_find_property(platdev->dev.of_node,
"dmas", NULL)) {
ourport->dma = devm_kzalloc(port->dev,
sizeof(*ourport->dma),
GFP_KERNEL);
if (!ourport->dma) {
ret = -ENOMEM;
goto err;
}
}
ourport->clk = clk_get(&platdev->dev, "uart");
if (IS_ERR(ourport->clk)) {
pr_err("%s: Controller clock not found\n",
dev_name(&platdev->dev));
ret = PTR_ERR(ourport->clk);
goto err;
}
ret = clk_prepare_enable(ourport->clk);
if (ret) {
pr_err("uart: clock failed to prepare+enable: %d\n", ret);
clk_put(ourport->clk);
goto err;
}
ret = s3c24xx_serial_enable_baudclk(ourport);
if (ret)
pr_warn("uart: failed to enable baudclk\n");
/* Keep all interrupts masked and cleared */
switch (ourport->info->type) {
case TYPE_S3C6400:
wr_regl(port, S3C64XX_UINTM, 0xf);
wr_regl(port, S3C64XX_UINTP, 0xf);
wr_regl(port, S3C64XX_UINTSP, 0xf);
break;
case TYPE_APPLE_S5L: {
unsigned int ucon;
ucon = rd_regl(port, S3C2410_UCON);
ucon &= ~(APPLE_S5L_UCON_TXTHRESH_ENA_MSK |
APPLE_S5L_UCON_RXTHRESH_ENA_MSK |
APPLE_S5L_UCON_RXTO_ENA_MSK);
wr_regl(port, S3C2410_UCON, ucon);
wr_regl(port, S3C2410_UTRSTAT, APPLE_S5L_UTRSTAT_ALL_FLAGS);
break;
}
default:
break;
}
dev_dbg(port->dev, "port: map=%pa, mem=%p, irq=%d (%d,%d), clock=%u\n",
&port->mapbase, port->membase, port->irq,
ourport->rx_irq, ourport->tx_irq, port->uartclk);
/* reset the fifos (and setup the uart) */
s3c24xx_serial_resetport(port, cfg);
return 0;
err:
port->mapbase = 0;
return ret;
}
/* Device driver serial port probe */
static int probe_index;
static inline const struct s3c24xx_serial_drv_data *
s3c24xx_get_driver_data(struct platform_device *pdev)
{
if (dev_of_node(&pdev->dev))
return of_device_get_match_data(&pdev->dev);
return (struct s3c24xx_serial_drv_data *)
platform_get_device_id(pdev)->driver_data;
}
static int s3c24xx_serial_probe(struct platform_device *pdev)
{
struct device_node *np = pdev->dev.of_node;
struct s3c24xx_uart_port *ourport;
int index = probe_index;
int ret, prop = 0;
if (np) {
ret = of_alias_get_id(np, "serial");
if (ret >= 0)
index = ret;
}
if (index >= ARRAY_SIZE(s3c24xx_serial_ports)) {
dev_err(&pdev->dev, "serial%d out of range\n", index);
return -EINVAL;
}
ourport = &s3c24xx_serial_ports[index];
s3c24xx_serial_init_port_default(index);
ourport->drv_data = s3c24xx_get_driver_data(pdev);
if (!ourport->drv_data) {
dev_err(&pdev->dev, "could not find driver data\n");
return -ENODEV;
}
ourport->baudclk = ERR_PTR(-EINVAL);
ourport->info = &ourport->drv_data->info;
ourport->cfg = (dev_get_platdata(&pdev->dev)) ?
dev_get_platdata(&pdev->dev) :
&ourport->drv_data->def_cfg;
switch (ourport->info->type) {
case TYPE_S3C24XX:
ourport->port.ops = &s3c24xx_serial_ops;
break;
case TYPE_S3C6400:
ourport->port.ops = &s3c64xx_serial_ops;
break;
case TYPE_APPLE_S5L:
ourport->port.ops = &apple_s5l_serial_ops;
break;
}
if (np) {
of_property_read_u32(np,
"samsung,uart-fifosize", &ourport->port.fifosize);
if (of_property_read_u32(np, "reg-io-width", &prop) == 0) {
switch (prop) {
case 1:
ourport->port.iotype = UPIO_MEM;
break;
case 4:
ourport->port.iotype = UPIO_MEM32;
break;
default:
dev_warn(&pdev->dev, "unsupported reg-io-width (%d)\n",
prop);
return -EINVAL;
}
}
}
if (ourport->drv_data->fifosize[index])
ourport->port.fifosize = ourport->drv_data->fifosize[index];
else if (ourport->info->fifosize)
ourport->port.fifosize = ourport->info->fifosize;
ourport->port.has_sysrq = IS_ENABLED(CONFIG_SERIAL_SAMSUNG_CONSOLE);
/*
* DMA transfers must be aligned at least to cache line size,
* so find minimal transfer size suitable for DMA mode
*/
ourport->min_dma_size = max_t(int, ourport->port.fifosize,
dma_get_cache_alignment());
dev_dbg(&pdev->dev, "%s: initialising port %p...\n", __func__, ourport);
ret = s3c24xx_serial_init_port(ourport, pdev);
if (ret < 0)
return ret;
if (!s3c24xx_uart_drv.state) {
ret = uart_register_driver(&s3c24xx_uart_drv);
if (ret < 0) {
pr_err("Failed to register Samsung UART driver\n");
return ret;
}
}
dev_dbg(&pdev->dev, "%s: adding port\n", __func__);
uart_add_one_port(&s3c24xx_uart_drv, &ourport->port);
platform_set_drvdata(pdev, &ourport->port);
/*
* Deactivate the clock enabled in s3c24xx_serial_init_port here,
* so that a potential re-enablement through the pm-callback overlaps
* and keeps the clock enabled in this case.
*/
clk_disable_unprepare(ourport->clk);
if (!IS_ERR(ourport->baudclk))
clk_disable_unprepare(ourport->baudclk);
probe_index++;
return 0;
}
static int s3c24xx_serial_remove(struct platform_device *dev)
{
struct uart_port *port = s3c24xx_dev_to_port(&dev->dev);
if (port) {
uart_remove_one_port(&s3c24xx_uart_drv, port);
}
uart_unregister_driver(&s3c24xx_uart_drv);
return 0;
}
/* UART power management code */
#ifdef CONFIG_PM_SLEEP
static int s3c24xx_serial_suspend(struct device *dev)
{
struct uart_port *port = s3c24xx_dev_to_port(dev);
if (port)
uart_suspend_port(&s3c24xx_uart_drv, port);
return 0;
}
static int s3c24xx_serial_resume(struct device *dev)
{
struct uart_port *port = s3c24xx_dev_to_port(dev);
struct s3c24xx_uart_port *ourport = to_ourport(port);
if (port) {
clk_prepare_enable(ourport->clk);
if (!IS_ERR(ourport->baudclk))
clk_prepare_enable(ourport->baudclk);
s3c24xx_serial_resetport(port, s3c24xx_port_to_cfg(port));
if (!IS_ERR(ourport->baudclk))
clk_disable_unprepare(ourport->baudclk);
clk_disable_unprepare(ourport->clk);
uart_resume_port(&s3c24xx_uart_drv, port);
}
return 0;
}
static int s3c24xx_serial_resume_noirq(struct device *dev)
{
struct uart_port *port = s3c24xx_dev_to_port(dev);
struct s3c24xx_uart_port *ourport = to_ourport(port);
if (port) {
/* restore IRQ mask */
switch (ourport->info->type) {
case TYPE_S3C6400: {
unsigned int uintm = 0xf;
if (ourport->tx_enabled)
uintm &= ~S3C64XX_UINTM_TXD_MSK;
if (ourport->rx_enabled)
uintm &= ~S3C64XX_UINTM_RXD_MSK;
clk_prepare_enable(ourport->clk);
if (!IS_ERR(ourport->baudclk))
clk_prepare_enable(ourport->baudclk);
wr_regl(port, S3C64XX_UINTM, uintm);
if (!IS_ERR(ourport->baudclk))
clk_disable_unprepare(ourport->baudclk);
clk_disable_unprepare(ourport->clk);
break;
}
case TYPE_APPLE_S5L: {
unsigned int ucon;
int ret;
ret = clk_prepare_enable(ourport->clk);
if (ret) {
dev_err(dev, "clk_enable clk failed: %d\n", ret);
return ret;
}
if (!IS_ERR(ourport->baudclk)) {
ret = clk_prepare_enable(ourport->baudclk);
if (ret) {
dev_err(dev, "clk_enable baudclk failed: %d\n", ret);
clk_disable_unprepare(ourport->clk);
return ret;
}
}
ucon = rd_regl(port, S3C2410_UCON);
ucon &= ~(APPLE_S5L_UCON_TXTHRESH_ENA_MSK |
APPLE_S5L_UCON_RXTHRESH_ENA_MSK |
APPLE_S5L_UCON_RXTO_ENA_MSK);
if (ourport->tx_enabled)
ucon |= APPLE_S5L_UCON_TXTHRESH_ENA_MSK;
if (ourport->rx_enabled)
ucon |= APPLE_S5L_UCON_RXTHRESH_ENA_MSK |
APPLE_S5L_UCON_RXTO_ENA_MSK;
wr_regl(port, S3C2410_UCON, ucon);
if (!IS_ERR(ourport->baudclk))
clk_disable_unprepare(ourport->baudclk);
clk_disable_unprepare(ourport->clk);
break;
}
default:
break;
}
}
return 0;
}
static const struct dev_pm_ops s3c24xx_serial_pm_ops = {
.suspend = s3c24xx_serial_suspend,
.resume = s3c24xx_serial_resume,
.resume_noirq = s3c24xx_serial_resume_noirq,
};
#define SERIAL_SAMSUNG_PM_OPS (&s3c24xx_serial_pm_ops)
#else /* !CONFIG_PM_SLEEP */
#define SERIAL_SAMSUNG_PM_OPS NULL
#endif /* CONFIG_PM_SLEEP */
/* Console code */
#ifdef CONFIG_SERIAL_SAMSUNG_CONSOLE
static struct uart_port *cons_uart;
static int
s3c24xx_serial_console_txrdy(struct uart_port *port, unsigned int ufcon)
{
const struct s3c24xx_uart_info *info = s3c24xx_port_to_info(port);
unsigned long ufstat, utrstat;
if (ufcon & S3C2410_UFCON_FIFOMODE) {
/* fifo mode - check amount of data in fifo registers... */
ufstat = rd_regl(port, S3C2410_UFSTAT);
return (ufstat & info->tx_fifofull) ? 0 : 1;
}
/* in non-fifo mode, we go and use the tx buffer empty */
utrstat = rd_regl(port, S3C2410_UTRSTAT);
return (utrstat & S3C2410_UTRSTAT_TXE) ? 1 : 0;
}
static bool
s3c24xx_port_configured(unsigned int ucon)
{
/* consider the serial port configured if the tx/rx mode set */
return (ucon & 0xf) != 0;
}
#ifdef CONFIG_CONSOLE_POLL
/*
* Console polling routines for writing and reading from the uart while
* in an interrupt or debug context.
*/
static int s3c24xx_serial_get_poll_char(struct uart_port *port)
{
const struct s3c24xx_uart_port *ourport = to_ourport(port);
unsigned int ufstat;
ufstat = rd_regl(port, S3C2410_UFSTAT);
if (s3c24xx_serial_rx_fifocnt(ourport, ufstat) == 0)
return NO_POLL_CHAR;
return rd_reg(port, S3C2410_URXH);
}
static void s3c24xx_serial_put_poll_char(struct uart_port *port,
unsigned char c)
{
unsigned int ufcon = rd_regl(port, S3C2410_UFCON);
unsigned int ucon = rd_regl(port, S3C2410_UCON);
/* not possible to xmit on unconfigured port */
if (!s3c24xx_port_configured(ucon))
return;
while (!s3c24xx_serial_console_txrdy(port, ufcon))
cpu_relax();
wr_reg(port, S3C2410_UTXH, c);
}
#endif /* CONFIG_CONSOLE_POLL */
static void
s3c24xx_serial_console_putchar(struct uart_port *port, unsigned char ch)
{
unsigned int ufcon = rd_regl(port, S3C2410_UFCON);
while (!s3c24xx_serial_console_txrdy(port, ufcon))
cpu_relax();
wr_reg(port, S3C2410_UTXH, ch);
}
static void
s3c24xx_serial_console_write(struct console *co, const char *s,
unsigned int count)
{
unsigned int ucon = rd_regl(cons_uart, S3C2410_UCON);
unsigned long flags;
bool locked = true;
/* not possible to xmit on unconfigured port */
if (!s3c24xx_port_configured(ucon))
return;
if (cons_uart->sysrq)
locked = false;
else if (oops_in_progress)
locked = spin_trylock_irqsave(&cons_uart->lock, flags);
else
spin_lock_irqsave(&cons_uart->lock, flags);
uart_console_write(cons_uart, s, count, s3c24xx_serial_console_putchar);
if (locked)
spin_unlock_irqrestore(&cons_uart->lock, flags);
}
/* Shouldn't be __init, as it can be instantiated from other module */
static void
s3c24xx_serial_get_options(struct uart_port *port, int *baud,
int *parity, int *bits)
{
struct clk *clk;
unsigned int ulcon;
unsigned int ucon;
unsigned int ubrdiv;
unsigned long rate;
unsigned int clk_sel;
char clk_name[MAX_CLK_NAME_LENGTH];
ulcon = rd_regl(port, S3C2410_ULCON);
ucon = rd_regl(port, S3C2410_UCON);
ubrdiv = rd_regl(port, S3C2410_UBRDIV);
if (s3c24xx_port_configured(ucon)) {
switch (ulcon & S3C2410_LCON_CSMASK) {
case S3C2410_LCON_CS5:
*bits = 5;
break;
case S3C2410_LCON_CS6:
*bits = 6;
break;
case S3C2410_LCON_CS7:
*bits = 7;
break;
case S3C2410_LCON_CS8:
default:
*bits = 8;
break;
}
switch (ulcon & S3C2410_LCON_PMASK) {
case S3C2410_LCON_PEVEN:
*parity = 'e';
break;
case S3C2410_LCON_PODD:
*parity = 'o';
break;
case S3C2410_LCON_PNONE:
default:
*parity = 'n';
}
/* now calculate the baud rate */
clk_sel = s3c24xx_serial_getsource(port);
sprintf(clk_name, "clk_uart_baud%d", clk_sel);
clk = clk_get(port->dev, clk_name);
if (!IS_ERR(clk))
rate = clk_get_rate(clk);
else
rate = 1;
*baud = rate / (16 * (ubrdiv + 1));
dev_dbg(port->dev, "calculated baud %d\n", *baud);
}
}
/* Shouldn't be __init, as it can be instantiated from other module */
static int
s3c24xx_serial_console_setup(struct console *co, char *options)
{
struct uart_port *port;
int baud = 9600;
int bits = 8;
int parity = 'n';
int flow = 'n';
/* is this a valid port */
if (co->index == -1 || co->index >= UART_NR)
co->index = 0;
port = &s3c24xx_serial_ports[co->index].port;
/* is the port configured? */
if (port->mapbase == 0x0)
return -ENODEV;
cons_uart = port;
/*
* Check whether an invalid uart number has been specified, and
* if so, search for the first available port that does have
* console support.
*/
if (options)
uart_parse_options(options, &baud, &parity, &bits, &flow);
else
s3c24xx_serial_get_options(port, &baud, &parity, &bits);
dev_dbg(port->dev, "baud %d\n", baud);
return uart_set_options(port, co, baud, parity, bits, flow);
}
static struct console s3c24xx_serial_console = {
.name = S3C24XX_SERIAL_NAME,
.device = uart_console_device,
.flags = CON_PRINTBUFFER,
.index = -1,
.write = s3c24xx_serial_console_write,
.setup = s3c24xx_serial_console_setup,
.data = &s3c24xx_uart_drv,
};
#endif /* CONFIG_SERIAL_SAMSUNG_CONSOLE */
#if defined(CONFIG_CPU_S3C6400) || defined(CONFIG_CPU_S3C6410)
static const struct s3c24xx_serial_drv_data s3c6400_serial_drv_data = {
.info = {
.name = "Samsung S3C6400 UART",
.type = TYPE_S3C6400,
.port_type = PORT_S3C6400,
.fifosize = 64,
.has_divslot = 1,
.rx_fifomask = S3C2440_UFSTAT_RXMASK,
.rx_fifoshift = S3C2440_UFSTAT_RXSHIFT,
.rx_fifofull = S3C2440_UFSTAT_RXFULL,
.tx_fifofull = S3C2440_UFSTAT_TXFULL,
.tx_fifomask = S3C2440_UFSTAT_TXMASK,
.tx_fifoshift = S3C2440_UFSTAT_TXSHIFT,
.def_clk_sel = S3C2410_UCON_CLKSEL2,
.num_clks = 4,
.clksel_mask = S3C6400_UCON_CLKMASK,
.clksel_shift = S3C6400_UCON_CLKSHIFT,
},
.def_cfg = {
.ucon = S3C2410_UCON_DEFAULT,
.ufcon = S3C2410_UFCON_DEFAULT,
},
};
#define S3C6400_SERIAL_DRV_DATA (&s3c6400_serial_drv_data)
#else
#define S3C6400_SERIAL_DRV_DATA NULL
#endif
#ifdef CONFIG_CPU_S5PV210
static const struct s3c24xx_serial_drv_data s5pv210_serial_drv_data = {
.info = {
.name = "Samsung S5PV210 UART",
.type = TYPE_S3C6400,
.port_type = PORT_S3C6400,
.has_divslot = 1,
.rx_fifomask = S5PV210_UFSTAT_RXMASK,
.rx_fifoshift = S5PV210_UFSTAT_RXSHIFT,
.rx_fifofull = S5PV210_UFSTAT_RXFULL,
.tx_fifofull = S5PV210_UFSTAT_TXFULL,
.tx_fifomask = S5PV210_UFSTAT_TXMASK,
.tx_fifoshift = S5PV210_UFSTAT_TXSHIFT,
.def_clk_sel = S3C2410_UCON_CLKSEL0,
.num_clks = 2,
.clksel_mask = S5PV210_UCON_CLKMASK,
.clksel_shift = S5PV210_UCON_CLKSHIFT,
},
.def_cfg = {
.ucon = S5PV210_UCON_DEFAULT,
.ufcon = S5PV210_UFCON_DEFAULT,
},
.fifosize = { 256, 64, 16, 16 },
};
#define S5PV210_SERIAL_DRV_DATA (&s5pv210_serial_drv_data)
#else
#define S5PV210_SERIAL_DRV_DATA NULL
#endif
#if defined(CONFIG_ARCH_EXYNOS)
#define EXYNOS_COMMON_SERIAL_DRV_DATA() \
.info = { \
.name = "Samsung Exynos UART", \
.type = TYPE_S3C6400, \
.port_type = PORT_S3C6400, \
.has_divslot = 1, \
.rx_fifomask = S5PV210_UFSTAT_RXMASK, \
.rx_fifoshift = S5PV210_UFSTAT_RXSHIFT, \
.rx_fifofull = S5PV210_UFSTAT_RXFULL, \
.tx_fifofull = S5PV210_UFSTAT_TXFULL, \
.tx_fifomask = S5PV210_UFSTAT_TXMASK, \
.tx_fifoshift = S5PV210_UFSTAT_TXSHIFT, \
.def_clk_sel = S3C2410_UCON_CLKSEL0, \
.num_clks = 1, \
.clksel_mask = 0, \
.clksel_shift = 0, \
}, \
.def_cfg = { \
.ucon = S5PV210_UCON_DEFAULT, \
.ufcon = S5PV210_UFCON_DEFAULT, \
.has_fracval = 1, \
} \
static const struct s3c24xx_serial_drv_data exynos4210_serial_drv_data = {
EXYNOS_COMMON_SERIAL_DRV_DATA(),
.fifosize = { 256, 64, 16, 16 },
};
static const struct s3c24xx_serial_drv_data exynos5433_serial_drv_data = {
EXYNOS_COMMON_SERIAL_DRV_DATA(),
.fifosize = { 64, 256, 16, 256 },
};
static const struct s3c24xx_serial_drv_data exynos850_serial_drv_data = {
EXYNOS_COMMON_SERIAL_DRV_DATA(),
.fifosize = { 256, 64, 64, 64 },
};
#define EXYNOS4210_SERIAL_DRV_DATA (&exynos4210_serial_drv_data)
#define EXYNOS5433_SERIAL_DRV_DATA (&exynos5433_serial_drv_data)
#define EXYNOS850_SERIAL_DRV_DATA (&exynos850_serial_drv_data)
#else
#define EXYNOS4210_SERIAL_DRV_DATA NULL
#define EXYNOS5433_SERIAL_DRV_DATA NULL
#define EXYNOS850_SERIAL_DRV_DATA NULL
#endif
#ifdef CONFIG_ARCH_APPLE
static const struct s3c24xx_serial_drv_data s5l_serial_drv_data = {
.info = {
.name = "Apple S5L UART",
.type = TYPE_APPLE_S5L,
.port_type = PORT_8250,
.fifosize = 16,
.rx_fifomask = S3C2410_UFSTAT_RXMASK,
.rx_fifoshift = S3C2410_UFSTAT_RXSHIFT,
.rx_fifofull = S3C2410_UFSTAT_RXFULL,
.tx_fifofull = S3C2410_UFSTAT_TXFULL,
.tx_fifomask = S3C2410_UFSTAT_TXMASK,
.tx_fifoshift = S3C2410_UFSTAT_TXSHIFT,
.def_clk_sel = S3C2410_UCON_CLKSEL0,
.num_clks = 1,
.clksel_mask = 0,
.clksel_shift = 0,
.ucon_mask = APPLE_S5L_UCON_MASK,
},
.def_cfg = {
.ucon = APPLE_S5L_UCON_DEFAULT,
.ufcon = S3C2410_UFCON_DEFAULT,
},
};
#define S5L_SERIAL_DRV_DATA (&s5l_serial_drv_data)
#else
#define S5L_SERIAL_DRV_DATA NULL
#endif
#if defined(CONFIG_ARCH_ARTPEC)
static const struct s3c24xx_serial_drv_data artpec8_serial_drv_data = {
.info = {
.name = "Axis ARTPEC-8 UART",
.type = TYPE_S3C6400,
.port_type = PORT_S3C6400,
.fifosize = 64,
.has_divslot = 1,
.rx_fifomask = S5PV210_UFSTAT_RXMASK,
.rx_fifoshift = S5PV210_UFSTAT_RXSHIFT,
.rx_fifofull = S5PV210_UFSTAT_RXFULL,
.tx_fifofull = S5PV210_UFSTAT_TXFULL,
.tx_fifomask = S5PV210_UFSTAT_TXMASK,
.tx_fifoshift = S5PV210_UFSTAT_TXSHIFT,
.def_clk_sel = S3C2410_UCON_CLKSEL0,
.num_clks = 1,
.clksel_mask = 0,
.clksel_shift = 0,
},
.def_cfg = {
.ucon = S5PV210_UCON_DEFAULT,
.ufcon = S5PV210_UFCON_DEFAULT,
.has_fracval = 1,
}
};
#define ARTPEC8_SERIAL_DRV_DATA (&artpec8_serial_drv_data)
#else
#define ARTPEC8_SERIAL_DRV_DATA (NULL)
#endif
static const struct platform_device_id s3c24xx_serial_driver_ids[] = {
{
.name = "s3c6400-uart",
.driver_data = (kernel_ulong_t)S3C6400_SERIAL_DRV_DATA,
}, {
.name = "s5pv210-uart",
.driver_data = (kernel_ulong_t)S5PV210_SERIAL_DRV_DATA,
}, {
.name = "exynos4210-uart",
.driver_data = (kernel_ulong_t)EXYNOS4210_SERIAL_DRV_DATA,
}, {
.name = "exynos5433-uart",
.driver_data = (kernel_ulong_t)EXYNOS5433_SERIAL_DRV_DATA,
}, {
.name = "s5l-uart",
.driver_data = (kernel_ulong_t)S5L_SERIAL_DRV_DATA,
}, {
.name = "exynos850-uart",
.driver_data = (kernel_ulong_t)EXYNOS850_SERIAL_DRV_DATA,
}, {
.name = "artpec8-uart",
.driver_data = (kernel_ulong_t)ARTPEC8_SERIAL_DRV_DATA,
},
{ },
};
MODULE_DEVICE_TABLE(platform, s3c24xx_serial_driver_ids);
#ifdef CONFIG_OF
static const struct of_device_id s3c24xx_uart_dt_match[] = {
{ .compatible = "samsung,s3c6400-uart",
.data = S3C6400_SERIAL_DRV_DATA },
{ .compatible = "samsung,s5pv210-uart",
.data = S5PV210_SERIAL_DRV_DATA },
{ .compatible = "samsung,exynos4210-uart",
.data = EXYNOS4210_SERIAL_DRV_DATA },
{ .compatible = "samsung,exynos5433-uart",
.data = EXYNOS5433_SERIAL_DRV_DATA },
{ .compatible = "apple,s5l-uart",
.data = S5L_SERIAL_DRV_DATA },
{ .compatible = "samsung,exynos850-uart",
.data = EXYNOS850_SERIAL_DRV_DATA },
{ .compatible = "axis,artpec8-uart",
.data = ARTPEC8_SERIAL_DRV_DATA },
{},
};
MODULE_DEVICE_TABLE(of, s3c24xx_uart_dt_match);
#endif
static struct platform_driver samsung_serial_driver = {
.probe = s3c24xx_serial_probe,
.remove = s3c24xx_serial_remove,
.id_table = s3c24xx_serial_driver_ids,
.driver = {
.name = "samsung-uart",
.pm = SERIAL_SAMSUNG_PM_OPS,
.of_match_table = of_match_ptr(s3c24xx_uart_dt_match),
},
};
static int __init samsung_serial_init(void)
{
int ret;
s3c24xx_serial_register_console();
ret = platform_driver_register(&samsung_serial_driver);
if (ret) {
s3c24xx_serial_unregister_console();
return ret;
}
return 0;
}
static void __exit samsung_serial_exit(void)
{
platform_driver_unregister(&samsung_serial_driver);
s3c24xx_serial_unregister_console();
}
module_init(samsung_serial_init);
module_exit(samsung_serial_exit);
#ifdef CONFIG_SERIAL_SAMSUNG_CONSOLE
/*
* Early console.
*/
static void wr_reg_barrier(const struct uart_port *port, u32 reg, u32 val)
{
switch (port->iotype) {
case UPIO_MEM:
writeb(val, portaddr(port, reg));
break;
case UPIO_MEM32:
writel(val, portaddr(port, reg));
break;
}
}
struct samsung_early_console_data {
u32 txfull_mask;
u32 rxfifo_mask;
};
static void samsung_early_busyuart(const struct uart_port *port)
{
while (!(readl(port->membase + S3C2410_UTRSTAT) & S3C2410_UTRSTAT_TXFE))
;
}
static void samsung_early_busyuart_fifo(const struct uart_port *port)
{
const struct samsung_early_console_data *data = port->private_data;
while (readl(port->membase + S3C2410_UFSTAT) & data->txfull_mask)
;
}
static void samsung_early_putc(struct uart_port *port, unsigned char c)
{
if (readl(port->membase + S3C2410_UFCON) & S3C2410_UFCON_FIFOMODE)
samsung_early_busyuart_fifo(port);
else
samsung_early_busyuart(port);
wr_reg_barrier(port, S3C2410_UTXH, c);
}
static void samsung_early_write(struct console *con, const char *s,
unsigned int n)
{
struct earlycon_device *dev = con->data;
uart_console_write(&dev->port, s, n, samsung_early_putc);
}
static int samsung_early_read(struct console *con, char *s, unsigned int n)
{
struct earlycon_device *dev = con->data;
const struct samsung_early_console_data *data = dev->port.private_data;
int ch, ufstat, num_read = 0;
while (num_read < n) {
ufstat = rd_regl(&dev->port, S3C2410_UFSTAT);
if (!(ufstat & data->rxfifo_mask))
break;
ch = rd_reg(&dev->port, S3C2410_URXH);
if (ch == NO_POLL_CHAR)
break;
s[num_read++] = ch;
}
return num_read;
}
static int __init samsung_early_console_setup(struct earlycon_device *device,
const char *opt)
{
if (!device->port.membase)
return -ENODEV;
device->con->write = samsung_early_write;
device->con->read = samsung_early_read;
return 0;
}
/* S3C2410 */
static struct samsung_early_console_data s3c2410_early_console_data = {
.txfull_mask = S3C2410_UFSTAT_TXFULL,
.rxfifo_mask = S3C2410_UFSTAT_RXFULL | S3C2410_UFSTAT_RXMASK,
};
static int __init s3c2410_early_console_setup(struct earlycon_device *device,
const char *opt)
{
device->port.private_data = &s3c2410_early_console_data;
return samsung_early_console_setup(device, opt);
}
OF_EARLYCON_DECLARE(s3c2410, "samsung,s3c2410-uart",
s3c2410_early_console_setup);
/* S3C2412, S3C2440, S3C64xx */
static struct samsung_early_console_data s3c2440_early_console_data = {
.txfull_mask = S3C2440_UFSTAT_TXFULL,
.rxfifo_mask = S3C2440_UFSTAT_RXFULL | S3C2440_UFSTAT_RXMASK,
};
static int __init s3c2440_early_console_setup(struct earlycon_device *device,
const char *opt)
{
device->port.private_data = &s3c2440_early_console_data;
return samsung_early_console_setup(device, opt);
}
OF_EARLYCON_DECLARE(s3c2412, "samsung,s3c2412-uart",
s3c2440_early_console_setup);
OF_EARLYCON_DECLARE(s3c2440, "samsung,s3c2440-uart",
s3c2440_early_console_setup);
OF_EARLYCON_DECLARE(s3c6400, "samsung,s3c6400-uart",
s3c2440_early_console_setup);
/* S5PV210, Exynos */
static struct samsung_early_console_data s5pv210_early_console_data = {
.txfull_mask = S5PV210_UFSTAT_TXFULL,
.rxfifo_mask = S5PV210_UFSTAT_RXFULL | S5PV210_UFSTAT_RXMASK,
};
static int __init s5pv210_early_console_setup(struct earlycon_device *device,
const char *opt)
{
device->port.private_data = &s5pv210_early_console_data;
return samsung_early_console_setup(device, opt);
}
OF_EARLYCON_DECLARE(s5pv210, "samsung,s5pv210-uart",
s5pv210_early_console_setup);
OF_EARLYCON_DECLARE(exynos4210, "samsung,exynos4210-uart",
s5pv210_early_console_setup);
OF_EARLYCON_DECLARE(artpec8, "axis,artpec8-uart",
s5pv210_early_console_setup);
/* Apple S5L */
static int __init apple_s5l_early_console_setup(struct earlycon_device *device,
const char *opt)
{
/* Close enough to S3C2410 for earlycon... */
device->port.private_data = &s3c2410_early_console_data;
#ifdef CONFIG_ARM64
/* ... but we need to override the existing fixmap entry as nGnRnE */
__set_fixmap(FIX_EARLYCON_MEM_BASE, device->port.mapbase,
__pgprot(PROT_DEVICE_nGnRnE));
#endif
return samsung_early_console_setup(device, opt);
}
OF_EARLYCON_DECLARE(s5l, "apple,s5l-uart", apple_s5l_early_console_setup);
#endif
MODULE_ALIAS("platform:samsung-uart");
MODULE_DESCRIPTION("Samsung SoC Serial port driver");
MODULE_AUTHOR("Ben Dooks <ben@simtec.co.uk>");
MODULE_LICENSE("GPL v2");
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