[PATCH v3 2/2] serial:sunplus-uart:Add Sunplus SoC UART Driver

From: Hammer Hsieh
Date: Fri Nov 19 2021 - 00:19:40 EST


Add Sunplus SoC UART Driver

Signed-off-by: Hammer Hsieh <hammer.hsieh@xxxxxxxxxxx>
---
Changes in v3:
- Addressed all comments from Andy Shevchenko and Philipp Zabel.

MAINTAINERS | 2 +
drivers/tty/serial/Kconfig | 23 +
drivers/tty/serial/Makefile | 1 +
drivers/tty/serial/sunplus-uart.c | 903 ++++++++++++++++++++++++++++++++++++++
include/soc/sunplus/sp_uart.h | 93 ++++
5 files changed, 1022 insertions(+)
create mode 100644 drivers/tty/serial/sunplus-uart.c
create mode 100644 include/soc/sunplus/sp_uart.h

diff --git a/MAINTAINERS b/MAINTAINERS
index f2ee40c..14790a4 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -17949,6 +17949,8 @@ SUNPLUS UART DRIVER
M: Hammer Hsieh <hammer.hsieh@xxxxxxxxxxx>
S: Maintained
F: Documentation/devicetree/bindings/serial/sunplus,sp7021-uart.yaml
+F: drivers/tty/serial/sunplus-uart.c
+F: include/soc/sunplus/sp-uart.h

SUPERH
M: Yoshinori Sato <ysato@xxxxxxxxxxxxxxxxxxxx>
diff --git a/drivers/tty/serial/Kconfig b/drivers/tty/serial/Kconfig
index 131a6a5..319f5db 100644
--- a/drivers/tty/serial/Kconfig
+++ b/drivers/tty/serial/Kconfig
@@ -1561,6 +1561,29 @@ config SERIAL_LITEUART_CONSOLE
and warnings and which allows logins in single user mode).
Otherwise, say 'N'.

+config SERIAL_SUNPLUS
+ bool "Sunplus UART support"
+ depends on OF
+ select SERIAL_CORE
+ help
+ Select this option if you would like to use Sunplus serial port on
+ Sunplus SoC SP7021.
+ If you enable this option, Sunplus serial ports in the system will
+ be registered as ttySx.
+
+config SERIAL_SUNPLUS_CONSOLE
+ bool "Console on Sunplus UART"
+ depends on SERIAL_SUNPLUS
+ select SERIAL_CORE_CONSOLE
+ select SERIAL_EARLYCON
+ help
+ Select this option if you would like to use a Sunplus UART as the
+ system console.
+ Even if you say Y here, the currently visible virtual console
+ (/dev/tty0) will still be used as the system console by default, but
+ you can alter that using a kernel command line option such as
+ "console=ttySx".
+
endmenu

config SERIAL_MCTRL_GPIO
diff --git a/drivers/tty/serial/Makefile b/drivers/tty/serial/Makefile
index 7da0856..61cc8de 100644
--- a/drivers/tty/serial/Makefile
+++ b/drivers/tty/serial/Makefile
@@ -87,6 +87,7 @@ obj-$(CONFIG_SERIAL_RDA) += rda-uart.o
obj-$(CONFIG_SERIAL_MILBEAUT_USIO) += milbeaut_usio.o
obj-$(CONFIG_SERIAL_SIFIVE) += sifive.o
obj-$(CONFIG_SERIAL_LITEUART) += liteuart.o
+obj-$(CONFIG_SERIAL_SUNPLUS) += sunplus-uart.o

# GPIOLIB helpers for modem control lines
obj-$(CONFIG_SERIAL_MCTRL_GPIO) += serial_mctrl_gpio.o
diff --git a/drivers/tty/serial/sunplus-uart.c b/drivers/tty/serial/sunplus-uart.c
new file mode 100644
index 0000000..b339772
--- /dev/null
+++ b/drivers/tty/serial/sunplus-uart.c
@@ -0,0 +1,903 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Sunplus SoC UART driver
+ *
+ * Author: Hammer Hsieh <hammer.hsieh@xxxxxxxxxxx>
+ * Tony Huang <tony.huang@xxxxxxxxxxx>
+ * Wells Lu <wells.lu@xxxxxxxxxxx>
+ *
+ */
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/console.h>
+#include <linux/interrupt.h>
+#include <linux/platform_device.h>
+#include <linux/tty.h>
+#include <linux/tty_flip.h>
+#include <linux/of_platform.h>
+#include <asm/irq.h>
+#include <linux/sysrq.h>
+#include <linux/serial_core.h>
+#include <linux/clk.h>
+#include <linux/reset.h>
+#include <linux/io.h>
+#include <linux/pm_runtime.h>
+#include <linux/of.h>
+#include <linux/delay.h>
+#include <soc/sunplus/sp_uart.h>
+
+#define UART_NR 5
+
+static struct uart_driver sunplus_uart_driver;
+
+struct sunplus_uart_port {
+ char name[16];
+ struct uart_port port;
+ struct clk *clk;
+ struct reset_control *rstc;
+};
+
+static inline struct sunplus_uart_port *to_sunplus_uart(struct uart_port *port)
+{
+ return container_of(port, struct sunplus_uart_port, port);
+}
+
+static inline void sp_uart_put_char(struct uart_port *port, unsigned int ch)
+{
+ writel(ch, port->membase + SP_UART_DATA);
+}
+
+static inline u32 sp_uart_line_status_tx_buf_not_full(struct uart_port *port)
+{
+ return ((readl(port->membase + SP_UART_LSR) & SP_UART_LSR_TX)
+ ? SP_UART_LSR_TX_NOT_FULL : 0);
+}
+
+static unsigned int sunplus_tx_empty(struct uart_port *port)
+{
+ return ((readl(port->membase + SP_UART_LSR) & SP_UART_LSR_TXE)
+ ? TIOCSER_TEMT : 0);
+}
+
+static void sunplus_set_mctrl(struct uart_port *port, unsigned int mctrl)
+{
+ unsigned int mcr = readl(port->membase + SP_UART_MCR);
+
+ if (mctrl & TIOCM_DTR)
+ mcr |= SP_UART_MCR_DTS;
+ else
+ mcr &= ~SP_UART_MCR_DTS;
+
+ if (mctrl & TIOCM_RTS)
+ mcr |= SP_UART_MCR_RTS;
+ else
+ mcr &= ~SP_UART_MCR_RTS;
+
+ if (mctrl & TIOCM_CAR)
+ mcr |= SP_UART_MCR_DCD;
+ else
+ mcr &= ~SP_UART_MCR_DCD;
+
+ if (mctrl & TIOCM_RI)
+ mcr |= SP_UART_MCR_RI;
+ else
+ mcr &= ~SP_UART_MCR_RI;
+
+ if (mctrl & TIOCM_LOOP)
+ mcr |= SP_UART_MCR_LB;
+ else
+ mcr &= ~SP_UART_MCR_LB;
+
+ writel(mcr, port->membase + SP_UART_MCR);
+
+}
+
+static unsigned int sunplus_get_mctrl(struct uart_port *port)
+{
+ unsigned int ret, mcr;
+
+ mcr = readl(port->membase + SP_UART_MCR);
+
+ if (mcr & SP_UART_MCR_DTS)
+ ret |= TIOCM_DTR;
+
+ if (mcr & SP_UART_MCR_RTS)
+ ret |= TIOCM_RTS;
+
+ if (mcr & SP_UART_MCR_DCD)
+ ret |= TIOCM_CAR;
+
+ if (mcr & SP_UART_MCR_RI)
+ ret |= TIOCM_RI;
+
+ if (mcr & SP_UART_MCR_LB)
+ ret |= TIOCM_LOOP;
+
+ if (mcr & SP_UART_MCR_AC)
+ ret |= TIOCM_CTS;
+
+ return ret;
+}
+
+static void sunplus_stop_tx(struct uart_port *port)
+{
+ unsigned int isc;
+
+ isc = readl(port->membase + SP_UART_ISC);
+ isc &= ~SP_UART_ISC_TXM;
+ writel(isc, port->membase + SP_UART_ISC);
+}
+
+static void sunplus_start_tx(struct uart_port *port)
+{
+ unsigned int isc;
+
+ isc = readl(port->membase + SP_UART_ISC);
+ isc |= SP_UART_ISC_TXM;
+ writel(isc, port->membase + SP_UART_ISC);
+}
+
+static void sunplus_stop_rx(struct uart_port *port)
+{
+ unsigned int isc;
+
+ isc = readl(port->membase + SP_UART_ISC);
+ isc &= ~SP_UART_ISC_RXM;
+ writel(isc, port->membase + SP_UART_ISC);
+}
+
+static void sunplus_enable_ms(struct uart_port *port)
+{
+ /* Do nothing */
+}
+
+static void sunplus_break_ctl(struct uart_port *port, int ctl)
+{
+ unsigned long flags;
+ unsigned int lcr;
+
+ spin_lock_irqsave(&port->lock, flags);
+
+ lcr = readl(port->membase + SP_UART_LCR);
+
+ if (ctl != 0)
+ lcr |= SP_UART_LCR_BC; /* start break */
+ else
+ lcr &= ~SP_UART_LCR_BC; /* stop break */
+
+ writel(lcr, port->membase + SP_UART_LCR);
+
+ spin_unlock_irqrestore(&port->lock, flags);
+}
+
+static void transmit_chars(struct uart_port *port)
+{
+ struct circ_buf *xmit = &port->state->xmit;
+
+ if (port->x_char) {
+ sp_uart_put_char(port, port->x_char);
+ port->icount.tx++;
+ port->x_char = 0;
+ return;
+ }
+
+ if (uart_circ_empty(xmit) || uart_tx_stopped(port)) {
+ sunplus_stop_tx(port);
+ return;
+ }
+
+ do {
+ sp_uart_put_char(port, xmit->buf[xmit->tail]);
+ xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
+ port->icount.tx++;
+
+ if (uart_circ_empty(xmit))
+ break;
+ } while (sp_uart_line_status_tx_buf_not_full(port));
+
+
+ if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
+ uart_write_wakeup(port);
+
+ if (uart_circ_empty(xmit))
+ sunplus_stop_tx(port);
+}
+
+/* called by ISR */
+static void receive_chars(struct uart_port *port)
+{
+ struct tty_struct *tty = port->state->port.tty;
+ unsigned int lsr = readl(port->membase + SP_UART_LSR);
+ unsigned int ch, flag;
+
+ do {
+ ch = readl(port->membase + SP_UART_DATA);
+
+ flag = TTY_NORMAL;
+ port->icount.rx++;
+
+ if (unlikely(lsr & SP_UART_LSR_BRK_ERROR_BITS)) {
+ if (port->cons == NULL)
+ dev_err(port->dev, "UART%d, SP_UART_LSR_BRK_ERROR_BITS, lsr = 0x%08X\n",
+ port->line, lsr);
+
+ if (lsr & SP_UART_LSR_BC) {
+ lsr &= ~(SP_UART_LSR_FE | SP_UART_LSR_PE);
+ port->icount.brk++;
+ if (uart_handle_break(port))
+ goto ignore_char;
+ } else if (lsr & SP_UART_LSR_PE) {
+ if (port->cons == NULL)
+ dev_err(port->dev, "UART%d, SP_UART_LSR_PE\n", port->line);
+ port->icount.parity++;
+ } else if (lsr & SP_UART_LSR_FE) {
+ if (port->cons == NULL)
+ dev_err(port->dev, "UART%d, SP_UART_LSR_FE\n", port->line);
+ port->icount.frame++;
+ }
+ if (lsr & SP_UART_LSR_OE) {
+ if (port->cons == NULL)
+ dev_err(port->dev, "UART%d, SP_UART_LSR_OE\n", port->line);
+ port->icount.overrun++;
+ }
+
+ /*
+ * Mask off conditions which should be ignored.
+ */
+
+ /* lsr &= port->read_status_mask; */
+
+ if (lsr & SP_UART_LSR_BC)
+ flag = TTY_BREAK;
+ else if (lsr & SP_UART_LSR_PE)
+ flag = TTY_PARITY;
+ else if (lsr & SP_UART_LSR_FE)
+ flag = TTY_FRAME;
+ }
+
+ if (port->ignore_status_mask & SP_UART_CREAD_DISABLED)
+ goto ignore_char;
+
+ if (uart_handle_sysrq_char(port, ch))
+ goto ignore_char;
+
+ uart_insert_char(port, lsr, SP_UART_LSR_OE, ch, flag);
+
+ignore_char:
+ lsr = readl(port->membase + SP_UART_LSR);
+ } while (lsr & SP_UART_LSR_RX);
+
+ if (tty) {
+ spin_unlock(&port->lock);
+ tty_flip_buffer_push(tty->port);
+ spin_lock(&port->lock);
+ }
+}
+
+static irqreturn_t sunplus_uart_irq(int irq, void *args)
+{
+ struct uart_port *port = (struct uart_port *)args;
+ unsigned long flags;
+
+ spin_lock_irqsave(&port->lock, flags);
+
+ if (readl(port->membase + SP_UART_ISC) & SP_UART_ISC_RX)
+ receive_chars(port);
+
+ if (readl(port->membase + SP_UART_ISC) & SP_UART_ISC_TX)
+ transmit_chars(port);
+
+ spin_unlock_irqrestore(&port->lock, flags);
+
+ return IRQ_HANDLED;
+}
+
+static int sunplus_startup(struct uart_port *port)
+{
+ struct sunplus_uart_port *sup = to_sunplus_uart(port);
+ u32 interrupt_en;
+ int ret;
+
+#ifdef CONFIG_PM_RUNTIME_UART
+ if (port->line > 0) {
+ ret = pm_runtime_get_sync(port->dev);
+ if (ret < 0)
+ goto out;
+ }
+#endif
+
+ ret = request_irq(port->irq, sunplus_uart_irq, 0, sup->name, port);
+ if (ret)
+ return ret;
+
+ /*
+ * don't need to use spin_lock_irqsave() because interrupts
+ * are globally disabled
+ */
+ spin_lock_irq(&port->lock);
+
+ /* SP_UART_ISC_TXM is enabled in .start_tx() */
+ interrupt_en |= SP_UART_ISC_RXM;
+
+ writel(interrupt_en, port->membase + SP_UART_ISC);
+
+ spin_unlock_irq(&port->lock);
+
+#ifdef CONFIG_PM_RUNTIME_UART
+ if (port->line > 0)
+ pm_runtime_put(port->dev);
+
+ return 0;
+
+out:
+ if (port->line > 0) {
+ pm_runtime_mark_last_busy(port->dev);
+ pm_runtime_put_autosuspend(port->dev);
+ }
+#endif
+ return 0;
+
+}
+
+static void sunplus_shutdown(struct uart_port *port)
+{
+ unsigned int mcr;
+ unsigned long flags;
+
+ spin_lock_irqsave(&port->lock, flags);
+ writel(0, port->membase + SP_UART_ISC);
+ spin_unlock_irqrestore(&port->lock, flags);
+
+ free_irq(port->irq, port);
+
+ /* Disable flow control of Tx, so that queued data can be sent out
+ * There is no way for s/w to let h/w abort in the middle of
+ * transaction.
+ * Don't reset module except it's in idle state. Otherwise, it might
+ * cause bus to hang.
+ */
+ mcr = readl(port->membase + SP_UART_MCR);
+ mcr &= ~SP_UART_MCR_AC;
+ writel(mcr, port->membase + SP_UART_MCR);
+
+}
+
+static void sunplus_set_termios(struct uart_port *port,
+ struct ktermios *termios, struct ktermios *oldtermios)
+{
+ u32 clk, ext, div, div_l, div_h, baud;
+ u32 lcr, mcr;
+ unsigned long flags;
+
+ clk = port->uartclk;
+
+ baud = uart_get_baud_rate(port, termios, oldtermios, 0, port->uartclk / 16);
+
+ /*
+ * Send all data in Tx FIFO before changing clock source,
+ * it should be UART0 only
+ */
+ while (!(readl(port->membase + SP_UART_LSR) & SP_UART_LSR_TXE))
+ ;
+
+ clk += baud >> 1;
+ div = clk / baud;
+ ext = div & 0x0F;
+ div = (div >> 4) - 1;
+ div_l = (div & 0xFF) | (ext << 12);
+ div_h = div >> 8;
+
+ switch (termios->c_cflag & CSIZE) {
+ case CS5:
+ lcr = SP_UART_LCR_WL5;
+ break;
+ case CS6:
+ lcr = SP_UART_LCR_WL6;
+ break;
+ case CS7:
+ lcr = SP_UART_LCR_WL7;
+ break;
+ default: /* CS8 */
+ lcr = SP_UART_LCR_WL8;
+ break;
+ }
+
+ if (termios->c_cflag & CSTOPB)
+ lcr |= SP_UART_LCR_ST;
+
+ if (termios->c_cflag & PARENB) {
+ lcr |= SP_UART_LCR_PE;
+
+ if (!(termios->c_cflag & PARODD))
+ lcr |= SP_UART_LCR_PR;
+ }
+
+ spin_lock_irqsave(&port->lock, flags);
+
+ uart_update_timeout(port, termios->c_cflag, baud);
+
+ port->read_status_mask = 0;
+ if (termios->c_iflag & INPCK)
+ port->read_status_mask |= SP_UART_LSR_PE | SP_UART_LSR_FE;
+
+ if (termios->c_iflag & (BRKINT | PARMRK))
+ port->read_status_mask |= SP_UART_LSR_BC;
+
+ /*
+ * Characters to ignore
+ */
+ port->ignore_status_mask = 0;
+ if (termios->c_iflag & IGNPAR)
+ port->ignore_status_mask |= SP_UART_LSR_FE | SP_UART_LSR_PE;
+
+ if (termios->c_iflag & IGNBRK) {
+ port->ignore_status_mask |= SP_UART_LSR_BC;
+
+ if (termios->c_iflag & IGNPAR)
+ port->ignore_status_mask |= SP_UART_LSR_OE;
+ }
+
+ /*
+ * Ignore all characters if CREAD is not set.
+ */
+ if ((termios->c_cflag & CREAD) == 0) {
+ port->ignore_status_mask |= SP_UART_CREAD_DISABLED;
+ /* flush rx data FIFO */
+ writel(0, port->membase + SP_UART_RX_RESIDUE);
+ }
+
+ mcr = readl(port->membase + SP_UART_MCR);
+
+ if (termios->c_cflag & CRTSCTS)
+ mcr |= (SP_UART_MCR_AC | SP_UART_MCR_AR);
+ else
+ mcr &= ~(SP_UART_MCR_AC | SP_UART_MCR_AR);
+
+ writel(mcr, port->membase + SP_UART_MCR);
+
+ /* do not set these in emulation */
+ writel(div_h, port->membase + SP_UART_DIV_H);
+ writel(div_l, port->membase + SP_UART_DIV_L);
+ writel(lcr, port->membase + SP_UART_LCR);
+
+ spin_unlock_irqrestore(&port->lock, flags);
+}
+
+static void sunplus_set_ldisc(struct uart_port *port,
+ struct ktermios *termios)
+{
+ int new = termios->c_line;
+
+ if (new == N_PPS) {
+ port->flags |= UPF_HARDPPS_CD;
+ sunplus_enable_ms(port);
+ } else {
+ port->flags &= ~UPF_HARDPPS_CD;
+ }
+}
+
+static const char *sunplus_type(struct uart_port *port)
+{
+ struct sunplus_uart_port *sup = to_sunplus_uart(port);
+
+ return sup->name;
+}
+
+static void sunplus_release_port(struct uart_port *port)
+{
+}
+
+static int sunplus_request_port(struct uart_port *port)
+{
+ return 0;
+}
+
+static void sunplus_config_port(struct uart_port *port, int type)
+{
+ if (type & UART_CONFIG_TYPE) {
+ port->type = PORT_SUNPLUS;
+ sunplus_request_port(port);
+ }
+}
+
+static int sunplus_verify_port(struct uart_port *port, struct serial_struct *serial)
+{
+ return -EINVAL;
+}
+
+#ifdef CONFIG_CONSOLE_POLL
+static int sunplus_poll_init(struct uart_port *port)
+{
+ return 0;
+}
+
+static void sunplus_poll_put_char(struct uart_port *port, unsigned char data)
+{
+ wait_for_xmitr(port);
+ sp_uart_put_char(port, data);
+}
+
+static int sunplus_poll_get_char(struct uart_port *port)
+{
+ unsigned int lsr;
+
+ do {
+ lsr = readl(port->membase + SP_UART_LSR);
+ } while (!(lsr & SP_UART_LSR_RX));
+
+ return readl(port->membase + SP_UART_DATA);
+}
+#endif /* CONFIG_CONSOLE_POLL */
+
+static const struct uart_ops sunplus_uart_ops = {
+ .tx_empty = sunplus_tx_empty,
+ .set_mctrl = sunplus_set_mctrl,
+ .get_mctrl = sunplus_get_mctrl,
+ .stop_tx = sunplus_stop_tx,
+ .start_tx = sunplus_start_tx,
+ .stop_rx = sunplus_stop_rx,
+ .enable_ms = sunplus_enable_ms,
+ .break_ctl = sunplus_break_ctl,
+ .startup = sunplus_startup,
+ .shutdown = sunplus_shutdown,
+ .set_termios = sunplus_set_termios,
+ .set_ldisc = sunplus_set_ldisc,
+ .type = sunplus_type,
+ .release_port = sunplus_release_port,
+ .request_port = sunplus_request_port,
+ .config_port = sunplus_config_port,
+ .verify_port = sunplus_verify_port,
+#ifdef CONFIG_CONSOLE_POLL
+ .poll_init = sunplus_poll_init,
+ .poll_put_char = sunplus_poll_put_char,
+ .poll_get_char = sunplus_poll_get_char,
+#endif /* CONFIG_CONSOLE_POLL */
+};
+
+#ifdef CONFIG_SERIAL_SUNPLUS_CONSOLE
+struct sunplus_uart_port *sunplus_console_ports[UART_NR];
+
+static inline void wait_for_xmitr(struct uart_port *port)
+{
+ while (1) {
+ if (sp_uart_line_status_tx_buf_not_full(port))
+ break;
+ }
+}
+
+static void sunplus_uart_console_putchar(struct uart_port *port, int ch)
+{
+ wait_for_xmitr(port);
+ sp_uart_put_char(port, ch);
+}
+
+static void sunplus_uart_console_write(struct console *co,
+ const char *s, unsigned int count)
+{
+ unsigned long flags;
+ int locked = 1;
+
+ local_irq_save(flags);
+
+ if (sunplus_console_ports[co->index]->port.sysrq)
+ locked = 0;
+ else if (oops_in_progress)
+ locked = spin_trylock(&sunplus_console_ports[co->index]->port.lock);
+ else
+ spin_lock(&sunplus_console_ports[co->index]->port.lock);
+
+ uart_console_write(&sunplus_console_ports[co->index]->port,
+ s, count, sunplus_uart_console_putchar);
+
+ if (locked)
+ spin_unlock(&sunplus_console_ports[co->index]->port.lock);
+
+ local_irq_restore(flags);
+}
+
+static int __init sunplus_uart_console_setup(struct console *co, char *options)
+{
+ struct sunplus_uart_port *sup;
+ int baud = 115200;
+ int bits = 8;
+ int parity = 'n';
+ int flow = 'n';
+
+ if ((co->index >= UART_NR) || (co->index < 0))
+ return -EINVAL;
+
+ sup = sunplus_console_ports[co->index];
+
+ if (options)
+ uart_parse_options(options, &baud, &parity, &bits, &flow);
+
+ return uart_set_options(&sup->port, co, baud, parity, bits, flow);
+}
+
+static struct console sunplus_uart_console = {
+ .name = "ttyS",
+ .write = sunplus_uart_console_write,
+ .device = uart_console_device,
+ .setup = sunplus_uart_console_setup,
+ .flags = CON_PRINTBUFFER,
+ .index = -1,
+ .data = &sunplus_uart_driver
+};
+#endif
+
+static struct uart_driver sunplus_uart_driver = {
+ .owner = THIS_MODULE,
+ .driver_name = "Sunplus_UART",
+ .dev_name = "ttyS",
+ .major = TTY_MAJOR,
+ .minor = 64,
+ .nr = UART_NR,
+ .cons = NULL,
+};
+
+static int sunplus_uart_probe(struct platform_device *pdev)
+{
+ struct sunplus_uart_port *sup;
+ struct resource *res_mem;
+ struct uart_port *port;
+ int ret, irq;
+
+ if (pdev->dev.of_node) {
+ pdev->id = of_alias_get_id(pdev->dev.of_node, "serial");
+ if (pdev->id < 0)
+ pdev->id = of_alias_get_id(pdev->dev.of_node, "uart");
+ }
+
+ if (pdev->id < 0 || pdev->id >= UART_NR)
+ return -EINVAL;
+
+ sup = devm_kzalloc(&pdev->dev, sizeof(struct sunplus_uart_port),
+ GFP_KERNEL);
+ if (!sup)
+ return -ENOMEM;
+
+ sup->clk = devm_clk_get(&pdev->dev, NULL);
+ if (IS_ERR(sup->clk)) {
+ dev_err(&pdev->dev, "unable to get UART clock\n");
+ return PTR_ERR(sup->clk);
+ }
+
+ sup->rstc = devm_reset_control_get_exclusive(&pdev->dev, NULL);
+ if (IS_ERR(sup->rstc))
+ return PTR_ERR(sup->rstc);
+
+ port = &sup->port;
+
+ res_mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ if (!res_mem)
+ return -ENODEV;
+
+ port->membase = devm_ioremap_resource(&pdev->dev, res_mem);
+ if (IS_ERR(port->membase))
+ return PTR_ERR(port->membase);
+
+ ret = clk_prepare_enable(sup->clk);
+ if (ret)
+ return ret;
+
+ port->uartclk = clk_get_rate(sup->clk);
+ if (!port->uartclk) {
+ ret = -EINVAL;
+ goto err_disable_clk;
+ }
+
+ irq = platform_get_irq(pdev, 0);
+ if (irq < 0)
+ return -ENODEV;
+
+ port->mapbase = res_mem->start;
+ port->line = pdev->id;
+ port->irq = irq;
+ port->dev = &pdev->dev;
+ port->iotype = UPIO_MEM;
+ port->ops = &sunplus_uart_ops;
+ port->flags = UPF_BOOT_AUTOCONF;
+ port->fifosize = 128;
+
+ ret = reset_control_deassert(sup->rstc);
+ if (ret)
+ return ret;
+
+#ifdef CONFIG_SERIAL_SUNPLUS_CONSOLE
+ if (pdev->id == 0)
+ port->cons = &sunplus_uart_console;
+ sunplus_console_ports[sup->port.line] = sup;
+#endif
+
+ port->private_data = container_of(&sup->port,
+ struct sunplus_uart_port, port);
+
+ sprintf(sup->name, "sp_uart%d", pdev->id);
+
+ ret = uart_add_one_port(&sunplus_uart_driver, &sup->port);
+ if (ret)
+ goto err_disable_clk;
+
+ platform_set_drvdata(pdev, sup);
+
+#ifdef CONFIG_PM_RUNTIME_UART
+ if (pdev->id != 0) {
+ pm_runtime_set_autosuspend_delay(&pdev->dev, 5000);
+ pm_runtime_use_autosuspend(&pdev->dev);
+ pm_runtime_set_active(&pdev->dev);
+ pm_runtime_enable(&pdev->dev);
+ }
+#endif
+ return 0;
+
+err_disable_clk:
+ clk_disable_unprepare(sup->clk);
+ return ret;
+
+}
+
+static int sunplus_uart_remove(struct platform_device *pdev)
+{
+ struct sunplus_uart_port *sup;
+
+ sup = platform_get_drvdata(pdev);
+#ifdef CONFIG_PM_RUNTIME_UART
+ if (pdev->id != 0) {
+ pm_runtime_disable(&pdev->dev);
+ pm_runtime_set_suspended(&pdev->dev);
+ }
+#endif
+ uart_remove_one_port(&sunplus_uart_driver, &sup->port);
+
+ if (pdev->id < UART_NR) {
+ clk_disable_unprepare(sup->clk);
+ reset_control_assert(sup->rstc);
+ }
+
+ return 0;
+}
+
+static int sunplus_uart_suspend(struct platform_device *pdev,
+ pm_message_t state)
+{
+ struct sunplus_uart_port *sup;
+
+ sup = platform_get_drvdata(pdev);
+
+ /* Don't suspend uart0 for cmd line usage */
+ if ((pdev->id < UART_NR) && (pdev->id > 0))
+ reset_control_assert(sup->rstc);
+
+ return 0;
+}
+
+static int sunplus_uart_resume(struct platform_device *pdev)
+{
+ struct sunplus_uart_port *sup;
+
+ sup = platform_get_drvdata(pdev);
+
+ if (pdev->id < UART_NR) {
+ clk_prepare_enable(sup->clk);
+ reset_control_deassert(sup->rstc);
+ }
+ return 0;
+}
+
+#ifdef CONFIG_PM_RUNTIME_UART
+static int sunplus_uart_runtime_suspend(struct device *dev)
+{
+ struct platform_device *pdev = to_platform_device(dev);
+ struct sunplus_uart_port *sup;
+
+ sup = platform_get_drvdata(pdev);
+
+ /* Don't suspend uart0 for cmd line usage */
+ if ((pdev->id < UART_NR) && (pdev->id > 0))
+ reset_control_assert(sup->rstc);
+
+ return 0;
+}
+
+static int sunplus_uart_runtime_resume(struct device *dev)
+{
+ struct platform_device *pdev = to_platform_device(dev);
+ struct sunplus_uart_port *sup;
+
+ sup = platform_get_drvdata(pdev);
+
+ if (pdev->id < UART_NR) {
+ clk_prepare_enable(sup->clk);
+ reset_control_deassert(sup->rstc);
+ }
+
+ return 0;
+}
+static const struct dev_pm_ops sp7021_uart_pm_ops = {
+ .runtime_suspend = sunplus_uart_runtime_suspend,
+ .runtime_resume = sunplus_uart_runtime_resume,
+};
+#define sunplus_uart_pm_ops (&sp7021_uart_pm_ops)
+#endif
+
+static const struct of_device_id sp_uart_of_match[] = {
+ { .compatible = "sunplus,sp7021-uart" },
+ {},
+};
+MODULE_DEVICE_TABLE(of, sp_uart_of_match);
+
+static struct platform_driver sunplus_uart_platform_driver = {
+ .probe = sunplus_uart_probe,
+ .remove = sunplus_uart_remove,
+ .suspend = sunplus_uart_suspend,
+ .resume = sunplus_uart_resume,
+ .driver = {
+ .name = "sunplus-uart",
+ .owner = THIS_MODULE,
+ .of_match_table = of_match_ptr(sp_uart_of_match),
+#ifdef CONFIG_PM_RUNTIME_UART
+ .pm = sunplus_uart_pm_ops,
+#endif
+ }
+};
+
+static int __init sunplus_uart_init(void)
+{
+ int ret;
+
+#ifdef CONFIG_SERIAL_SUNPLUS_CONSOLE
+ sunplus_uart_driver.cons = &sunplus_uart_console;
+#endif
+
+ ret = uart_register_driver(&sunplus_uart_driver);
+ if (ret < 0)
+ return ret;
+
+ ret = platform_driver_register(&sunplus_uart_platform_driver);
+ if (ret != 0) {
+ uart_unregister_driver(&sunplus_uart_driver);
+ return ret;
+ }
+
+ return 0;
+}
+module_init(sunplus_uart_init);
+
+#ifdef CONFIG_SERIAL_EARLYCON
+static void sunplus_uart_putc(struct uart_port *port, int c)
+{
+ unsigned int status;
+
+ for (;;) {
+ status = readl(port->membase + SP_UART_LSR);
+ if ((status & SP_UART_LSR_TXE) == SP_UART_LSR_TXE)
+ break;
+ cpu_relax();
+ }
+ writel(c, port->membase + SP_UART_DATA);
+}
+
+static void sunplus_uart_early_write(struct console *con,
+ const char *s, unsigned int n)
+{
+ struct earlycon_device *dev = con->data;
+
+ uart_console_write(&dev->port, s, n, sunplus_uart_putc);
+}
+
+int __init sunplus_uart_early_setup(struct earlycon_device *device,
+ const char *opt)
+{
+ if (!(device->port.membase || device->port.iobase))
+ return -ENODEV;
+
+ device->con->write = sunplus_uart_early_write;
+ return 0;
+}
+OF_EARLYCON_DECLARE(sunplus_uart, "sunplus,sp7021-uart", sunplus_uart_early_setup);
+#endif
+
+MODULE_DESCRIPTION("Sunplus UART driver");
+MODULE_AUTHOR("Hammer Hsieh <hammer.hsieh@xxxxxxxxxxx>");
+MODULE_LICENSE("GPL v2");
diff --git a/include/soc/sunplus/sp_uart.h b/include/soc/sunplus/sp_uart.h
new file mode 100644
index 0000000..c34c8d0
--- /dev/null
+++ b/include/soc/sunplus/sp_uart.h
@@ -0,0 +1,93 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Sunplus SoC UART driver header file
+ */
+
+#ifndef __SP_UART_H__
+#define __SP_UART_H__
+
+#ifdef CONFIG_DEBUG_SP_UART
+#include <mach/io_map.h>
+
+#define LL_UART_PADDR PA_IOB_ADDR(18 * 32 * 4)
+#define LL_UART_VADDR VA_IOB_ADDR(18 * 32 * 4)
+#define LOGI_ADDR_UART0_REG VA_IOB_ADDR(18 * 32 * 4)
+#endif
+
+/*
+ * UART REG
+ *
+ */
+#define SP_UART_DATA 0x00
+#define SP_UART_LSR 0x04
+#define SP_UART_MSR 0x08
+#define SP_UART_LCR 0x0C
+#define SP_UART_MCR 0x10
+#define SP_UART_DIV_L 0x14
+#define SP_UART_DIV_H 0x18
+#define SP_UART_ISC 0x1C
+#define SP_UART_TX_RESIDUE 0x20
+#define SP_UART_RX_RESIDUE 0x24
+
+/* lsr
+ * 1: trasmit fifo is empty
+ */
+#define SP_UART_LSR_TXE (1 << 6)
+
+/* interrupt
+ * SP_UART_LSR_BC : break condition
+ * SP_UART_LSR_FE : frame error
+ * SP_UART_LSR_OE : overrun error
+ * SP_UART_LSR_PE : parity error
+ * SP_UART_LSR_RX : 1: receive fifo not empty
+ * SP_UART_LSR_TX : 1: transmit fifo is not full
+ */
+#define SP_UART_CREAD_DISABLED (1 << 16)
+#define SP_UART_LSR_BC (1 << 5)
+#define SP_UART_LSR_FE (1 << 4)
+#define SP_UART_LSR_OE (1 << 3)
+#define SP_UART_LSR_PE (1 << 2)
+#define SP_UART_LSR_RX (1 << 1)
+#define SP_UART_LSR_TX (1 << 0)
+#define SP_UART_LSR_TX_NOT_FULL 1
+
+#define SP_UART_LSR_BRK_ERROR_BITS \
+ (SP_UART_LSR_PE | SP_UART_LSR_OE | SP_UART_LSR_FE | SP_UART_LSR_BC)
+
+/* lcr */
+#define SP_UART_LCR_WL5 (0 << 0)
+#define SP_UART_LCR_WL6 (1 << 0)
+#define SP_UART_LCR_WL7 (2 << 0)
+#define SP_UART_LCR_WL8 (3 << 0)
+#define SP_UART_LCR_ST (1 << 2)
+#define SP_UART_LCR_PE (1 << 3)
+#define SP_UART_LCR_PR (1 << 4)
+#define SP_UART_LCR_BC (1 << 5)
+
+/* isc
+ * SP_UART_ISC_MSM : Modem status ctrl
+ * SP_UART_ISC_LSM : Line status interrupt
+ * SP_UART_ISC_RXM : RX interrupt, when got some input data
+ * SP_UART_ISC_TXM : TX interrupt, when trans start
+ */
+#define SP_UART_ISC_MSM (1 << 7)
+#define SP_UART_ISC_LSM (1 << 6)
+#define SP_UART_ISC_RXM (1 << 5)
+#define SP_UART_ISC_TXM (1 << 4)
+#define HAS_UART_ISC_FLAGMASK 0x0F
+#define SP_UART_ISC_MS (1 << 3)
+#define SP_UART_ISC_LS (1 << 2)
+#define SP_UART_ISC_RX (1 << 1)
+#define SP_UART_ISC_TX (1 << 0)
+
+/* modem control register */
+#define SP_UART_MCR_AT (1 << 7)
+#define SP_UART_MCR_AC (1 << 6)
+#define SP_UART_MCR_AR (1 << 5)
+#define SP_UART_MCR_LB (1 << 4)
+#define SP_UART_MCR_RI (1 << 3)
+#define SP_UART_MCR_DCD (1 << 2)
+#define SP_UART_MCR_RTS (1 << 1)
+#define SP_UART_MCR_DTS (1 << 0)
+
+#endif /* __SP_UART_H__ */
--
2.7.4