Commit 09864c1c authored by Stefan-gabriel Mirea's avatar Stefan-gabriel Mirea Committed by Greg Kroah-Hartman

tty: serial: Add linflexuart driver for S32V234

Introduce support for LINFlex driver, based on:
- the version of Freescale LPUART driver after commit b3e3bf2e ("Merge
  4.0-rc7 into tty-next");
- commit abf1e0a9 ("tty: serial: fsl_lpuart: lock port on console
  write").
In this basic version, the driver can be tested using initramfs and relies
on the clocks and pin muxing set up by U-Boot.

Remarks concerning the earlycon support:

- LinFlexD does not allow character transmissions in the INIT mode (see
  section 47.4.2.1 in the reference manual[1]). Therefore, a mutual
  exclusion between the first linflex_setup_watermark/linflex_set_termios
  executions and linflex_earlycon_putchar was employed and the characters
  normally sent to earlycon during initialization are kept in a buffer and
  sent afterwards.

- Empirically, character transmission is also forbidden within the last 1-2
  ms before entering the INIT mode, so we use an explicit timeout
  (PREINIT_DELAY) between linflex_earlycon_putchar and the first call to
  linflex_setup_watermark.

- U-Boot currently uses the UART FIFO mode, while this driver makes the
  transition to the buffer mode. Therefore, the earlycon putchar function
  matches the U-Boot behavior before initializations and the Linux behavior
  after.

[1] https://www.nxp.com/webapp/Download?colCode=S32V234RMSigned-off-by: default avatarStoica Cosmin-Stefan <cosmin.stoica@nxp.com>
Signed-off-by: default avatarAdrian.Nitu <adrian.nitu@freescale.com>
Signed-off-by: default avatarLarisa Grigore <Larisa.Grigore@nxp.com>
Signed-off-by: default avatarAna Nedelcu <B56683@freescale.com>
Signed-off-by: default avatarMihaela Martinas <Mihaela.Martinas@freescale.com>
Signed-off-by: default avatarMatthew Nunez <matthew.nunez@nxp.com>
[stefan-gabriel.mirea@nxp.com: Reduced for upstreaming and implemented
                               earlycon support]
Signed-off-by: default avatarStefan-Gabriel Mirea <stefan-gabriel.mirea@nxp.com>
Link: https://lore.kernel.org/r/20190809112853.15846-6-stefan-gabriel.mirea@nxp.comSigned-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent 8d41ab87
......@@ -1090,6 +1090,12 @@
the framebuffer, pass the 'ram' option so that it is
mapped with the correct attributes.
linflex,<addr>
Use early console provided by Freescale LinFlex UART
serial driver for NXP S32V234 SoCs. A valid base
address must be provided, and the serial port must
already be setup and configured.
earlyprintk= [X86,SH,ARM,M68k,S390]
earlyprintk=vga
earlyprintk=sclp
......
......@@ -1416,6 +1416,21 @@ config SERIAL_FSL_LPUART_CONSOLE
If you have enabled the lpuart serial port on the Freescale SoCs,
you can make it the console by answering Y to this option.
config SERIAL_FSL_LINFLEXUART
tristate "Freescale linflexuart serial port support"
select SERIAL_CORE
help
Support for the on-chip linflexuart on some Freescale SOCs.
config SERIAL_FSL_LINFLEXUART_CONSOLE
bool "Console on Freescale linflexuart serial port"
depends on SERIAL_FSL_LINFLEXUART=y
select SERIAL_CORE_CONSOLE
select SERIAL_EARLYCON
help
If you have enabled the linflexuart serial port on the Freescale
SoCs, you can make it the console by answering Y to this option.
config SERIAL_CONEXANT_DIGICOLOR
tristate "Conexant Digicolor CX92xxx USART serial port support"
depends on OF
......
......@@ -80,6 +80,7 @@ obj-$(CONFIG_SERIAL_EFM32_UART) += efm32-uart.o
obj-$(CONFIG_SERIAL_ARC) += arc_uart.o
obj-$(CONFIG_SERIAL_RP2) += rp2.o
obj-$(CONFIG_SERIAL_FSL_LPUART) += fsl_lpuart.o
obj-$(CONFIG_SERIAL_FSL_LINFLEXUART) += fsl_linflexuart.o
obj-$(CONFIG_SERIAL_CONEXANT_DIGICOLOR) += digicolor-usart.o
obj-$(CONFIG_SERIAL_MEN_Z135) += men_z135_uart.o
obj-$(CONFIG_SERIAL_SPRD) += sprd_serial.o
......
// SPDX-License-Identifier: GPL-2.0-or-later
/*
* Freescale linflexuart serial port driver
*
* Copyright 2012-2016 Freescale Semiconductor, Inc.
* Copyright 2017-2018 NXP
*/
#if defined(CONFIG_SERIAL_FSL_LINFLEXUART_CONSOLE) && \
defined(CONFIG_MAGIC_SYSRQ)
#define SUPPORT_SYSRQ
#endif
#include <linux/console.h>
#include <linux/io.h>
#include <linux/irq.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/of_device.h>
#include <linux/serial_core.h>
#include <linux/slab.h>
#include <linux/tty_flip.h>
#include <linux/delay.h>
/* All registers are 32-bit width */
#define LINCR1 0x0000 /* LIN control register */
#define LINIER 0x0004 /* LIN interrupt enable register */
#define LINSR 0x0008 /* LIN status register */
#define LINESR 0x000C /* LIN error status register */
#define UARTCR 0x0010 /* UART mode control register */
#define UARTSR 0x0014 /* UART mode status register */
#define LINTCSR 0x0018 /* LIN timeout control status register */
#define LINOCR 0x001C /* LIN output compare register */
#define LINTOCR 0x0020 /* LIN timeout control register */
#define LINFBRR 0x0024 /* LIN fractional baud rate register */
#define LINIBRR 0x0028 /* LIN integer baud rate register */
#define LINCFR 0x002C /* LIN checksum field register */
#define LINCR2 0x0030 /* LIN control register 2 */
#define BIDR 0x0034 /* Buffer identifier register */
#define BDRL 0x0038 /* Buffer data register least significant */
#define BDRM 0x003C /* Buffer data register most significant */
#define IFER 0x0040 /* Identifier filter enable register */
#define IFMI 0x0044 /* Identifier filter match index */
#define IFMR 0x0048 /* Identifier filter mode register */
#define GCR 0x004C /* Global control register */
#define UARTPTO 0x0050 /* UART preset timeout register */
#define UARTCTO 0x0054 /* UART current timeout register */
/*
* Register field definitions
*/
#define LINFLEXD_LINCR1_INIT BIT(0)
#define LINFLEXD_LINCR1_MME BIT(4)
#define LINFLEXD_LINCR1_BF BIT(7)
#define LINFLEXD_LINSR_LINS_INITMODE BIT(12)
#define LINFLEXD_LINSR_LINS_MASK (0xF << 12)
#define LINFLEXD_LINIER_SZIE BIT(15)
#define LINFLEXD_LINIER_OCIE BIT(14)
#define LINFLEXD_LINIER_BEIE BIT(13)
#define LINFLEXD_LINIER_CEIE BIT(12)
#define LINFLEXD_LINIER_HEIE BIT(11)
#define LINFLEXD_LINIER_FEIE BIT(8)
#define LINFLEXD_LINIER_BOIE BIT(7)
#define LINFLEXD_LINIER_LSIE BIT(6)
#define LINFLEXD_LINIER_WUIE BIT(5)
#define LINFLEXD_LINIER_DBFIE BIT(4)
#define LINFLEXD_LINIER_DBEIETOIE BIT(3)
#define LINFLEXD_LINIER_DRIE BIT(2)
#define LINFLEXD_LINIER_DTIE BIT(1)
#define LINFLEXD_LINIER_HRIE BIT(0)
#define LINFLEXD_UARTCR_OSR_MASK (0xF << 24)
#define LINFLEXD_UARTCR_OSR(uartcr) (((uartcr) \
& LINFLEXD_UARTCR_OSR_MASK) >> 24)
#define LINFLEXD_UARTCR_ROSE BIT(23)
#define LINFLEXD_UARTCR_RFBM BIT(9)
#define LINFLEXD_UARTCR_TFBM BIT(8)
#define LINFLEXD_UARTCR_WL1 BIT(7)
#define LINFLEXD_UARTCR_PC1 BIT(6)
#define LINFLEXD_UARTCR_RXEN BIT(5)
#define LINFLEXD_UARTCR_TXEN BIT(4)
#define LINFLEXD_UARTCR_PC0 BIT(3)
#define LINFLEXD_UARTCR_PCE BIT(2)
#define LINFLEXD_UARTCR_WL0 BIT(1)
#define LINFLEXD_UARTCR_UART BIT(0)
#define LINFLEXD_UARTSR_SZF BIT(15)
#define LINFLEXD_UARTSR_OCF BIT(14)
#define LINFLEXD_UARTSR_PE3 BIT(13)
#define LINFLEXD_UARTSR_PE2 BIT(12)
#define LINFLEXD_UARTSR_PE1 BIT(11)
#define LINFLEXD_UARTSR_PE0 BIT(10)
#define LINFLEXD_UARTSR_RMB BIT(9)
#define LINFLEXD_UARTSR_FEF BIT(8)
#define LINFLEXD_UARTSR_BOF BIT(7)
#define LINFLEXD_UARTSR_RPS BIT(6)
#define LINFLEXD_UARTSR_WUF BIT(5)
#define LINFLEXD_UARTSR_4 BIT(4)
#define LINFLEXD_UARTSR_TO BIT(3)
#define LINFLEXD_UARTSR_DRFRFE BIT(2)
#define LINFLEXD_UARTSR_DTFTFF BIT(1)
#define LINFLEXD_UARTSR_NF BIT(0)
#define LINFLEXD_UARTSR_PE (LINFLEXD_UARTSR_PE0 |\
LINFLEXD_UARTSR_PE1 |\
LINFLEXD_UARTSR_PE2 |\
LINFLEXD_UARTSR_PE3)
#define LINFLEX_LDIV_MULTIPLIER (16)
#define DRIVER_NAME "fsl-linflexuart"
#define DEV_NAME "ttyLF"
#define UART_NR 4
#define EARLYCON_BUFFER_INITIAL_CAP 8
#define PREINIT_DELAY 2000 /* us */
static const struct of_device_id linflex_dt_ids[] = {
{
.compatible = "fsl,s32-linflexuart",
},
{ /* sentinel */ }
};
MODULE_DEVICE_TABLE(of, linflex_dt_ids);
#ifdef CONFIG_SERIAL_FSL_LINFLEXUART_CONSOLE
static struct uart_port *earlycon_port;
static bool linflex_earlycon_same_instance;
static spinlock_t init_lock;
static bool during_init;
static struct {
char *content;
unsigned int len, cap;
} earlycon_buf;
#endif
static void linflex_stop_tx(struct uart_port *port)
{
unsigned long ier;
ier = readl(port->membase + LINIER);
ier &= ~(LINFLEXD_LINIER_DTIE);
writel(ier, port->membase + LINIER);
}
static void linflex_stop_rx(struct uart_port *port)
{
unsigned long ier;
ier = readl(port->membase + LINIER);
writel(ier & ~LINFLEXD_LINIER_DRIE, port->membase + LINIER);
}
static inline void linflex_transmit_buffer(struct uart_port *sport)
{
struct circ_buf *xmit = &sport->state->xmit;
unsigned char c;
unsigned long status;
while (!uart_circ_empty(xmit)) {
c = xmit->buf[xmit->tail];
writeb(c, sport->membase + BDRL);
/* Waiting for data transmission completed. */
while (((status = readl(sport->membase + UARTSR)) &
LINFLEXD_UARTSR_DTFTFF) !=
LINFLEXD_UARTSR_DTFTFF)
;
xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
sport->icount.tx++;
writel(status | LINFLEXD_UARTSR_DTFTFF,
sport->membase + UARTSR);
}
if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
uart_write_wakeup(sport);
if (uart_circ_empty(xmit))
linflex_stop_tx(sport);
}
static void linflex_start_tx(struct uart_port *port)
{
unsigned long ier;
linflex_transmit_buffer(port);
ier = readl(port->membase + LINIER);
writel(ier | LINFLEXD_LINIER_DTIE, port->membase + LINIER);
}
static irqreturn_t linflex_txint(int irq, void *dev_id)
{
struct uart_port *sport = dev_id;
struct circ_buf *xmit = &sport->state->xmit;
unsigned long flags;
unsigned long status;
spin_lock_irqsave(&sport->lock, flags);
if (sport->x_char) {
writeb(sport->x_char, sport->membase + BDRL);
/* waiting for data transmission completed */
while (((status = readl(sport->membase + UARTSR)) &
LINFLEXD_UARTSR_DTFTFF) != LINFLEXD_UARTSR_DTFTFF)
;
writel(status | LINFLEXD_UARTSR_DTFTFF,
sport->membase + UARTSR);
goto out;
}
if (uart_circ_empty(xmit) || uart_tx_stopped(sport)) {
linflex_stop_tx(sport);
goto out;
}
linflex_transmit_buffer(sport);
if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
uart_write_wakeup(sport);
out:
spin_unlock_irqrestore(&sport->lock, flags);
return IRQ_HANDLED;
}
static irqreturn_t linflex_rxint(int irq, void *dev_id)
{
struct uart_port *sport = dev_id;
unsigned int flg;
struct tty_port *port = &sport->state->port;
unsigned long flags, status;
unsigned char rx;
spin_lock_irqsave(&sport->lock, flags);
status = readl(sport->membase + UARTSR);
while (status & LINFLEXD_UARTSR_RMB) {
rx = readb(sport->membase + BDRM);
flg = TTY_NORMAL;
sport->icount.rx++;
if (status & (LINFLEXD_UARTSR_BOF | LINFLEXD_UARTSR_SZF |
LINFLEXD_UARTSR_FEF | LINFLEXD_UARTSR_PE)) {
if (status & LINFLEXD_UARTSR_SZF)
status |= LINFLEXD_UARTSR_SZF;
if (status & LINFLEXD_UARTSR_BOF)
status |= LINFLEXD_UARTSR_BOF;
if (status & LINFLEXD_UARTSR_FEF)
status |= LINFLEXD_UARTSR_FEF;
if (status & LINFLEXD_UARTSR_PE)
status |= LINFLEXD_UARTSR_PE;
}
writel(status | LINFLEXD_UARTSR_RMB | LINFLEXD_UARTSR_DRFRFE,
sport->membase + UARTSR);
status = readl(sport->membase + UARTSR);
if (uart_handle_sysrq_char(sport, (unsigned char)rx))
continue;
#ifdef SUPPORT_SYSRQ
sport->sysrq = 0;
#endif
tty_insert_flip_char(port, rx, flg);
}
spin_unlock_irqrestore(&sport->lock, flags);
tty_flip_buffer_push(port);
return IRQ_HANDLED;
}
static irqreturn_t linflex_int(int irq, void *dev_id)
{
struct uart_port *sport = dev_id;
unsigned long status;
status = readl(sport->membase + UARTSR);
if (status & LINFLEXD_UARTSR_DRFRFE)
linflex_rxint(irq, dev_id);
if (status & LINFLEXD_UARTSR_DTFTFF)
linflex_txint(irq, dev_id);
return IRQ_HANDLED;
}
/* return TIOCSER_TEMT when transmitter is not busy */
static unsigned int linflex_tx_empty(struct uart_port *port)
{
unsigned long status;
status = readl(port->membase + UARTSR) & LINFLEXD_UARTSR_DTFTFF;
return status ? TIOCSER_TEMT : 0;
}
static unsigned int linflex_get_mctrl(struct uart_port *port)
{
return 0;
}
static void linflex_set_mctrl(struct uart_port *port, unsigned int mctrl)
{
}
static void linflex_break_ctl(struct uart_port *port, int break_state)
{
}
static void linflex_setup_watermark(struct uart_port *sport)
{
unsigned long cr, ier, cr1;
/* Disable transmission/reception */
ier = readl(sport->membase + LINIER);
ier &= ~(LINFLEXD_LINIER_DRIE | LINFLEXD_LINIER_DTIE);
writel(ier, sport->membase + LINIER);
cr = readl(sport->membase + UARTCR);
cr &= ~(LINFLEXD_UARTCR_RXEN | LINFLEXD_UARTCR_TXEN);
writel(cr, sport->membase + UARTCR);
/* Enter initialization mode by setting INIT bit */
/* set the Linflex in master mode and activate by-pass filter */
cr1 = LINFLEXD_LINCR1_BF | LINFLEXD_LINCR1_MME
| LINFLEXD_LINCR1_INIT;
writel(cr1, sport->membase + LINCR1);
/* wait for init mode entry */
while ((readl(sport->membase + LINSR)
& LINFLEXD_LINSR_LINS_MASK)
!= LINFLEXD_LINSR_LINS_INITMODE)
;
/*
* UART = 0x1; - Linflex working in UART mode
* TXEN = 0x1; - Enable transmission of data now
* RXEn = 0x1; - Receiver enabled
* WL0 = 0x1; - 8 bit data
* PCE = 0x0; - No parity
*/
/* set UART bit to allow writing other bits */
writel(LINFLEXD_UARTCR_UART, sport->membase + UARTCR);
cr = (LINFLEXD_UARTCR_RXEN | LINFLEXD_UARTCR_TXEN |
LINFLEXD_UARTCR_WL0 | LINFLEXD_UARTCR_UART);
writel(cr, sport->membase + UARTCR);
cr1 &= ~(LINFLEXD_LINCR1_INIT);
writel(cr1, sport->membase + LINCR1);
ier = readl(sport->membase + LINIER);
ier |= LINFLEXD_LINIER_DRIE;
ier |= LINFLEXD_LINIER_DTIE;
writel(ier, sport->membase + LINIER);
}
static int linflex_startup(struct uart_port *port)
{
int ret = 0;
unsigned long flags;
spin_lock_irqsave(&port->lock, flags);
linflex_setup_watermark(port);
spin_unlock_irqrestore(&port->lock, flags);
ret = devm_request_irq(port->dev, port->irq, linflex_int, 0,
DRIVER_NAME, port);
return ret;
}
static void linflex_shutdown(struct uart_port *port)
{
unsigned long ier;
unsigned long flags;
spin_lock_irqsave(&port->lock, flags);
/* disable interrupts */
ier = readl(port->membase + LINIER);
ier &= ~(LINFLEXD_LINIER_DRIE | LINFLEXD_LINIER_DTIE);
writel(ier, port->membase + LINIER);
spin_unlock_irqrestore(&port->lock, flags);
devm_free_irq(port->dev, port->irq, port);
}
static void
linflex_set_termios(struct uart_port *port, struct ktermios *termios,
struct ktermios *old)
{
unsigned long flags;
unsigned long cr, old_cr, cr1;
unsigned int old_csize = old ? old->c_cflag & CSIZE : CS8;
cr = readl(port->membase + UARTCR);
old_cr = cr;
/* Enter initialization mode by setting INIT bit */
cr1 = readl(port->membase + LINCR1);
cr1 |= LINFLEXD_LINCR1_INIT;
writel(cr1, port->membase + LINCR1);
/* wait for init mode entry */
while ((readl(port->membase + LINSR)
& LINFLEXD_LINSR_LINS_MASK)
!= LINFLEXD_LINSR_LINS_INITMODE)
;
/*
* only support CS8 and CS7, and for CS7 must enable PE.
* supported mode:
* - (7,e/o,1)
* - (8,n,1)
* - (8,e/o,1)
*/
/* enter the UART into configuration mode */
while ((termios->c_cflag & CSIZE) != CS8 &&
(termios->c_cflag & CSIZE) != CS7) {
termios->c_cflag &= ~CSIZE;
termios->c_cflag |= old_csize;
old_csize = CS8;
}
if ((termios->c_cflag & CSIZE) == CS7) {
/* Word length: WL1WL0:00 */
cr = old_cr & ~LINFLEXD_UARTCR_WL1 & ~LINFLEXD_UARTCR_WL0;
}
if ((termios->c_cflag & CSIZE) == CS8) {
/* Word length: WL1WL0:01 */
cr = (old_cr | LINFLEXD_UARTCR_WL0) & ~LINFLEXD_UARTCR_WL1;
}
if (termios->c_cflag & CMSPAR) {
if ((termios->c_cflag & CSIZE) != CS8) {
termios->c_cflag &= ~CSIZE;
termios->c_cflag |= CS8;
}
/* has a space/sticky bit */
cr |= LINFLEXD_UARTCR_WL0;
}
if (termios->c_cflag & CSTOPB)
termios->c_cflag &= ~CSTOPB;
/* parity must be enabled when CS7 to match 8-bits format */
if ((termios->c_cflag & CSIZE) == CS7)
termios->c_cflag |= PARENB;
if ((termios->c_cflag & PARENB)) {
cr |= LINFLEXD_UARTCR_PCE;
if (termios->c_cflag & PARODD)
cr = (cr | LINFLEXD_UARTCR_PC0) &
(~LINFLEXD_UARTCR_PC1);
else
cr = cr & (~LINFLEXD_UARTCR_PC1 &
~LINFLEXD_UARTCR_PC0);
} else {
cr &= ~LINFLEXD_UARTCR_PCE;
}
spin_lock_irqsave(&port->lock, flags);
port->read_status_mask = 0;
if (termios->c_iflag & INPCK)
port->read_status_mask |= (LINFLEXD_UARTSR_FEF |
LINFLEXD_UARTSR_PE0 |
LINFLEXD_UARTSR_PE1 |
LINFLEXD_UARTSR_PE2 |
LINFLEXD_UARTSR_PE3);
if (termios->c_iflag & (IGNBRK | BRKINT | PARMRK))
port->read_status_mask |= LINFLEXD_UARTSR_FEF;
/* characters to ignore */
port->ignore_status_mask = 0;
if (termios->c_iflag & IGNPAR)
port->ignore_status_mask |= LINFLEXD_UARTSR_PE;
if (termios->c_iflag & IGNBRK) {
port->ignore_status_mask |= LINFLEXD_UARTSR_PE;
/*
* if we're ignoring parity and break indicators,
* ignore overruns too (for real raw support).
*/
if (termios->c_iflag & IGNPAR)
port->ignore_status_mask |= LINFLEXD_UARTSR_BOF;
}
writel(cr, port->membase + UARTCR);
cr1 &= ~(LINFLEXD_LINCR1_INIT);
writel(cr1, port->membase + LINCR1);
spin_unlock_irqrestore(&port->lock, flags);
}
static const char *linflex_type(struct uart_port *port)
{
return "FSL_LINFLEX";
}
static void linflex_release_port(struct uart_port *port)
{
/* nothing to do */
}
static int linflex_request_port(struct uart_port *port)
{
return 0;
}
/* configure/auto-configure the port */
static void linflex_config_port(struct uart_port *port, int flags)
{
if (flags & UART_CONFIG_TYPE)
port->type = PORT_LINFLEXUART;
}
static const struct uart_ops linflex_pops = {
.tx_empty = linflex_tx_empty,
.set_mctrl = linflex_set_mctrl,
.get_mctrl = linflex_get_mctrl,
.stop_tx = linflex_stop_tx,
.start_tx = linflex_start_tx,
.stop_rx = linflex_stop_rx,
.break_ctl = linflex_break_ctl,
.startup = linflex_startup,
.shutdown = linflex_shutdown,
.set_termios = linflex_set_termios,
.type = linflex_type,
.request_port = linflex_request_port,
.release_port = linflex_release_port,
.config_port = linflex_config_port,
};
static struct uart_port *linflex_ports[UART_NR];
#ifdef CONFIG_SERIAL_FSL_LINFLEXUART_CONSOLE
static void linflex_console_putchar(struct uart_port *port, int ch)
{
unsigned long cr;
cr = readl(port->membase + UARTCR);
writeb(ch, port->membase + BDRL);
if (!(cr & LINFLEXD_UARTCR_TFBM))
while ((readl(port->membase + UARTSR) &
LINFLEXD_UARTSR_DTFTFF)
!= LINFLEXD_UARTSR_DTFTFF)
;
else
while (readl(port->membase + UARTSR) &
LINFLEXD_UARTSR_DTFTFF)
;
if (!(cr & LINFLEXD_UARTCR_TFBM)) {
writel((readl(port->membase + UARTSR) |
LINFLEXD_UARTSR_DTFTFF),
port->membase + UARTSR);
}
}
static void linflex_earlycon_putchar(struct uart_port *port, int ch)
{
unsigned long flags;
char *ret;
if (!linflex_earlycon_same_instance) {
linflex_console_putchar(port, ch);
return;
}
spin_lock_irqsave(&init_lock, flags);
if (!during_init)
goto outside_init;
if (earlycon_buf.len >= 1 << CONFIG_LOG_BUF_SHIFT)
goto init_release;
if (!earlycon_buf.cap) {
earlycon_buf.content = kmalloc(EARLYCON_BUFFER_INITIAL_CAP,
GFP_ATOMIC);
earlycon_buf.cap = earlycon_buf.content ?
EARLYCON_BUFFER_INITIAL_CAP : 0;
} else if (earlycon_buf.len == earlycon_buf.cap) {
ret = krealloc(earlycon_buf.content, earlycon_buf.cap << 1,
GFP_ATOMIC);
if (ret) {
earlycon_buf.content = ret;
earlycon_buf.cap <<= 1;
}
}
if (earlycon_buf.len < earlycon_buf.cap)
earlycon_buf.content[earlycon_buf.len++] = ch;
goto init_release;
outside_init:
linflex_console_putchar(port, ch);
init_release:
spin_unlock_irqrestore(&init_lock, flags);
}
static void linflex_string_write(struct uart_port *sport, const char *s,
unsigned int count)
{
unsigned long cr, ier = 0;
ier = readl(sport->membase + LINIER);
linflex_stop_tx(sport);
cr = readl(sport->membase + UARTCR);
cr |= (LINFLEXD_UARTCR_TXEN);
writel(cr, sport->membase + UARTCR);
uart_console_write(sport, s, count, linflex_console_putchar);
writel(ier, sport->membase + LINIER);
}
static void
linflex_console_write(struct console *co, const char *s, unsigned int count)
{
struct uart_port *sport = linflex_ports[co->index];
unsigned long flags;
int locked = 1;
if (sport->sysrq)
locked = 0;
else if (oops_in_progress)
locked = spin_trylock_irqsave(&sport->lock, flags);
else
spin_lock_irqsave(&sport->lock, flags);
linflex_string_write(sport, s, count);
if (locked)
spin_unlock_irqrestore(&sport->lock, flags);
}
/*
* if the port was already initialised (eg, by a boot loader),
* try to determine the current setup.
*/
static void __init
linflex_console_get_options(struct uart_port *sport, int *parity, int *bits)
{
unsigned long cr;
cr = readl(sport->membase + UARTCR);
cr &= LINFLEXD_UARTCR_RXEN | LINFLEXD_UARTCR_TXEN;
if (!cr)
return;
/* ok, the port was enabled */
*parity = 'n';
if (cr & LINFLEXD_UARTCR_PCE) {
if (cr & LINFLEXD_UARTCR_PC0)
*parity = 'o';
else
*parity = 'e';
}
if ((cr & LINFLEXD_UARTCR_WL0) && ((cr & LINFLEXD_UARTCR_WL1) == 0)) {
if (cr & LINFLEXD_UARTCR_PCE)
*bits = 9;
else
*bits = 8;
}
}
static int __init linflex_console_setup(struct console *co, char *options)
{
struct uart_port *sport;
int baud = 115200;
int bits = 8;
int parity = 'n';
int flow = 'n';
int ret;
int i;
unsigned long flags;
/*
* check whether an invalid uart number has been specified, and
* if so, search for the first available port that does have
* console support.
*/
if (co->index == -1 || co->index >= ARRAY_SIZE(linflex_ports))
co->index = 0;
sport = linflex_ports[co->index];
if (!sport)
return -ENODEV;
if (options)
uart_parse_options(options, &baud, &parity, &bits, &flow);
else
linflex_console_get_options(sport, &parity, &bits);
if (earlycon_port && sport->mapbase == earlycon_port->mapbase) {
linflex_earlycon_same_instance = true;
spin_lock_irqsave(&init_lock, flags);
during_init = true;
spin_unlock_irqrestore(&init_lock, flags);
/* Workaround for character loss or output of many invalid
* characters, when INIT mode is entered shortly after a
* character has just been printed.
*/
udelay(PREINIT_DELAY);
}
linflex_setup_watermark(sport);
ret = uart_set_options(sport, co, baud, parity, bits, flow);
if (!linflex_earlycon_same_instance)
goto done;
spin_lock_irqsave(&init_lock, flags);
/* Emptying buffer */
if (earlycon_buf.len) {
for (i = 0; i < earlycon_buf.len; i++)
linflex_console_putchar(earlycon_port,
earlycon_buf.content[i]);
kfree(earlycon_buf.content);
earlycon_buf.len = 0;
}
during_init = false;
spin_unlock_irqrestore(&init_lock, flags);
done:
return ret;
}
static struct uart_driver linflex_reg;
static struct console linflex_console = {
.name = DEV_NAME,
.write = linflex_console_write,
.device = uart_console_device,
.setup = linflex_console_setup,
.flags = CON_PRINTBUFFER,
.index = -1,
.data = &linflex_reg,
};
static void linflex_earlycon_write(struct console *con, const char *s,
unsigned int n)
{
struct earlycon_device *dev = con->data;
uart_console_write(&dev->port, s, n, linflex_earlycon_putchar);
}
static int __init linflex_early_console_setup(struct earlycon_device *device,
const char *options)
{
if (!device->port.membase)
return -ENODEV;
device->con->write = linflex_earlycon_write;
earlycon_port = &device->port;
return 0;
}
OF_EARLYCON_DECLARE(linflex, "fsl,s32-linflexuart",
linflex_early_console_setup);
#define LINFLEX_CONSOLE (&linflex_console)
#else
#define LINFLEX_CONSOLE NULL
#endif
static struct uart_driver linflex_reg = {
.owner = THIS_MODULE,
.driver_name = DRIVER_NAME,
.dev_name = DEV_NAME,
.nr = ARRAY_SIZE(linflex_ports),
.cons = LINFLEX_CONSOLE,
};
static int linflex_probe(struct platform_device *pdev)
{
struct device_node *np = pdev->dev.of_node;
struct uart_port *sport;
struct resource *res;
int ret;
sport = devm_kzalloc(&pdev->dev, sizeof(*sport), GFP_KERNEL);
if (!sport)
return -ENOMEM;
ret = of_alias_get_id(np, "serial");
if (ret < 0) {
dev_err(&pdev->dev, "failed to get alias id, errno %d\n", ret);
return ret;
}
if (ret >= UART_NR) {
dev_err(&pdev->dev, "driver limited to %d serial ports\n",
UART_NR);
return -ENOMEM;
}
sport->line = ret;
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
if (!res)
return -ENODEV;
sport->mapbase = res->start;
sport->membase = devm_ioremap_resource(&pdev->dev, res);
if (IS_ERR(sport->membase))
return PTR_ERR(sport->membase);
sport->dev = &pdev->dev;
sport->type = PORT_LINFLEXUART;
sport->iotype = UPIO_MEM;
sport->irq = platform_get_irq(pdev, 0);
sport->ops = &linflex_pops;
sport->flags = UPF_BOOT_AUTOCONF;
linflex_ports[sport->line] = sport;
platform_set_drvdata(pdev, sport);
ret = uart_add_one_port(&linflex_reg, sport);
if (ret)
return ret;
return 0;
}
static int linflex_remove(struct platform_device *pdev)
{
struct uart_port *sport = platform_get_drvdata(pdev);
uart_remove_one_port(&linflex_reg, sport);
return 0;
}
#ifdef CONFIG_PM_SLEEP
static int linflex_suspend(struct device *dev)
{
struct uart_port *sport = dev_get_drvdata(dev);
uart_suspend_port(&linflex_reg, sport);
return 0;
}
static int linflex_resume(struct device *dev)
{
struct uart_port *sport = dev_get_drvdata(dev);
uart_resume_port(&linflex_reg, sport);
return 0;
}
#endif
static SIMPLE_DEV_PM_OPS(linflex_pm_ops, linflex_suspend, linflex_resume);
static struct platform_driver linflex_driver = {
.probe = linflex_probe,
.remove = linflex_remove,
.driver = {
.name = DRIVER_NAME,
.owner = THIS_MODULE,
.of_match_table = linflex_dt_ids,
.pm = &linflex_pm_ops,
},
};
static int __init linflex_serial_init(void)
{
int ret;
ret = uart_register_driver(&linflex_reg);
if (ret)
return ret;
ret = platform_driver_register(&linflex_driver);
if (ret)
uart_unregister_driver(&linflex_reg);
#ifdef CONFIG_SERIAL_FSL_LINFLEXUART_CONSOLE
spin_lock_init(&init_lock);
#endif
return ret;
}
static void __exit linflex_serial_exit(void)
{
platform_driver_unregister(&linflex_driver);
uart_unregister_driver(&linflex_reg);
}
module_init(linflex_serial_init);
module_exit(linflex_serial_exit);
MODULE_DESCRIPTION("Freescale linflex serial port driver");
MODULE_LICENSE("GPL v2");
......@@ -290,4 +290,7 @@
/* Sunix UART */
#define PORT_SUNIX 121
/* Freescale Linflex UART */
#define PORT_LINFLEXUART 121
#endif /* _UAPILINUX_SERIAL_CORE_H */
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