diff options
-rw-r--r-- | Documentation/admin-guide/kernel-parameters.txt | 6 | ||||
-rw-r--r-- | drivers/tty/serial/Kconfig | 15 | ||||
-rw-r--r-- | drivers/tty/serial/Makefile | 1 | ||||
-rw-r--r-- | drivers/tty/serial/fsl_linflexuart.c | 942 | ||||
-rw-r--r-- | include/uapi/linux/serial_core.h | 3 |
5 files changed, 967 insertions, 0 deletions
diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt index 47d981a86e2f..9ee66d61986b 100644 --- a/Documentation/admin-guide/kernel-parameters.txt +++ b/Documentation/admin-guide/kernel-parameters.txt @@ -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 diff --git a/drivers/tty/serial/Kconfig b/drivers/tty/serial/Kconfig index 7041107ea78d..db524e2c6db3 100644 --- a/drivers/tty/serial/Kconfig +++ b/drivers/tty/serial/Kconfig @@ -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 diff --git a/drivers/tty/serial/Makefile b/drivers/tty/serial/Makefile index 7f744136489e..490d74533fbd 100644 --- a/drivers/tty/serial/Makefile +++ b/drivers/tty/serial/Makefile @@ -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 diff --git a/drivers/tty/serial/fsl_linflexuart.c b/drivers/tty/serial/fsl_linflexuart.c new file mode 100644 index 000000000000..26b9601a0952 --- /dev/null +++ b/drivers/tty/serial/fsl_linflexuart.c @@ -0,0 +1,942 @@ +// 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"); diff --git a/include/uapi/linux/serial_core.h b/include/uapi/linux/serial_core.h index bd0d9d176a66..0f4f87a6fd54 100644 --- a/include/uapi/linux/serial_core.h +++ b/include/uapi/linux/serial_core.h @@ -290,4 +290,7 @@ /* Sunix UART */ #define PORT_SUNIX 121 +/* Freescale Linflex UART */ +#define PORT_LINFLEXUART 121 + #endif /* _UAPILINUX_SERIAL_CORE_H */ |