145c054d0SPaul Walmsley // SPDX-License-Identifier: GPL-2.0+
245c054d0SPaul Walmsley /*
345c054d0SPaul Walmsley * SiFive UART driver
445c054d0SPaul Walmsley * Copyright (C) 2018 Paul Walmsley <paul@pwsan.com>
545c054d0SPaul Walmsley * Copyright (C) 2018-2019 SiFive
645c054d0SPaul Walmsley *
745c054d0SPaul Walmsley * Based partially on:
845c054d0SPaul Walmsley * - drivers/tty/serial/pxa.c
945c054d0SPaul Walmsley * - drivers/tty/serial/amba-pl011.c
1045c054d0SPaul Walmsley * - drivers/tty/serial/uartlite.c
1145c054d0SPaul Walmsley * - drivers/tty/serial/omap-serial.c
1245c054d0SPaul Walmsley * - drivers/pwm/pwm-sifive.c
1345c054d0SPaul Walmsley *
1445c054d0SPaul Walmsley * See the following sources for further documentation:
1545c054d0SPaul Walmsley * - Chapter 19 "Universal Asynchronous Receiver/Transmitter (UART)" of
1645c054d0SPaul Walmsley * SiFive FE310-G000 v2p3
1745c054d0SPaul Walmsley * - The tree/master/src/main/scala/devices/uart directory of
1845c054d0SPaul Walmsley * https://github.com/sifive/sifive-blocks/
1945c054d0SPaul Walmsley *
2045c054d0SPaul Walmsley * The SiFive UART design is not 8250-compatible. The following common
2145c054d0SPaul Walmsley * features are not supported:
2245c054d0SPaul Walmsley * - Word lengths other than 8 bits
2345c054d0SPaul Walmsley * - Break handling
2445c054d0SPaul Walmsley * - Parity
2545c054d0SPaul Walmsley * - Flow control
2645c054d0SPaul Walmsley * - Modem signals (DSR, RI, etc.)
2745c054d0SPaul Walmsley * On the other hand, the design is free from the baggage of the 8250
2845c054d0SPaul Walmsley * programming model.
2945c054d0SPaul Walmsley */
3045c054d0SPaul Walmsley
3145c054d0SPaul Walmsley #include <linux/clk.h>
3245c054d0SPaul Walmsley #include <linux/console.h>
3345c054d0SPaul Walmsley #include <linux/delay.h>
3445c054d0SPaul Walmsley #include <linux/init.h>
3545c054d0SPaul Walmsley #include <linux/io.h>
3645c054d0SPaul Walmsley #include <linux/irq.h>
3745c054d0SPaul Walmsley #include <linux/module.h>
3845c054d0SPaul Walmsley #include <linux/of.h>
3945c054d0SPaul Walmsley #include <linux/of_irq.h>
4045c054d0SPaul Walmsley #include <linux/platform_device.h>
4145c054d0SPaul Walmsley #include <linux/serial_core.h>
4245c054d0SPaul Walmsley #include <linux/serial_reg.h>
4345c054d0SPaul Walmsley #include <linux/slab.h>
4445c054d0SPaul Walmsley #include <linux/tty.h>
4545c054d0SPaul Walmsley #include <linux/tty_flip.h>
4645c054d0SPaul Walmsley
4745c054d0SPaul Walmsley /*
4845c054d0SPaul Walmsley * Register offsets
4945c054d0SPaul Walmsley */
5045c054d0SPaul Walmsley
5145c054d0SPaul Walmsley /* TXDATA */
5245c054d0SPaul Walmsley #define SIFIVE_SERIAL_TXDATA_OFFS 0x0
5345c054d0SPaul Walmsley #define SIFIVE_SERIAL_TXDATA_FULL_SHIFT 31
5445c054d0SPaul Walmsley #define SIFIVE_SERIAL_TXDATA_FULL_MASK (1 << SIFIVE_SERIAL_TXDATA_FULL_SHIFT)
5545c054d0SPaul Walmsley #define SIFIVE_SERIAL_TXDATA_DATA_SHIFT 0
5645c054d0SPaul Walmsley #define SIFIVE_SERIAL_TXDATA_DATA_MASK (0xff << SIFIVE_SERIAL_TXDATA_DATA_SHIFT)
5745c054d0SPaul Walmsley
5845c054d0SPaul Walmsley /* RXDATA */
5945c054d0SPaul Walmsley #define SIFIVE_SERIAL_RXDATA_OFFS 0x4
6045c054d0SPaul Walmsley #define SIFIVE_SERIAL_RXDATA_EMPTY_SHIFT 31
6145c054d0SPaul Walmsley #define SIFIVE_SERIAL_RXDATA_EMPTY_MASK (1 << SIFIVE_SERIAL_RXDATA_EMPTY_SHIFT)
6245c054d0SPaul Walmsley #define SIFIVE_SERIAL_RXDATA_DATA_SHIFT 0
6345c054d0SPaul Walmsley #define SIFIVE_SERIAL_RXDATA_DATA_MASK (0xff << SIFIVE_SERIAL_RXDATA_DATA_SHIFT)
6445c054d0SPaul Walmsley
6545c054d0SPaul Walmsley /* TXCTRL */
6645c054d0SPaul Walmsley #define SIFIVE_SERIAL_TXCTRL_OFFS 0x8
6745c054d0SPaul Walmsley #define SIFIVE_SERIAL_TXCTRL_TXCNT_SHIFT 16
6845c054d0SPaul Walmsley #define SIFIVE_SERIAL_TXCTRL_TXCNT_MASK (0x7 << SIFIVE_SERIAL_TXCTRL_TXCNT_SHIFT)
6945c054d0SPaul Walmsley #define SIFIVE_SERIAL_TXCTRL_NSTOP_SHIFT 1
7045c054d0SPaul Walmsley #define SIFIVE_SERIAL_TXCTRL_NSTOP_MASK (1 << SIFIVE_SERIAL_TXCTRL_NSTOP_SHIFT)
7145c054d0SPaul Walmsley #define SIFIVE_SERIAL_TXCTRL_TXEN_SHIFT 0
7245c054d0SPaul Walmsley #define SIFIVE_SERIAL_TXCTRL_TXEN_MASK (1 << SIFIVE_SERIAL_TXCTRL_TXEN_SHIFT)
7345c054d0SPaul Walmsley
7445c054d0SPaul Walmsley /* RXCTRL */
7545c054d0SPaul Walmsley #define SIFIVE_SERIAL_RXCTRL_OFFS 0xC
7645c054d0SPaul Walmsley #define SIFIVE_SERIAL_RXCTRL_RXCNT_SHIFT 16
7745c054d0SPaul Walmsley #define SIFIVE_SERIAL_RXCTRL_RXCNT_MASK (0x7 << SIFIVE_SERIAL_TXCTRL_TXCNT_SHIFT)
7845c054d0SPaul Walmsley #define SIFIVE_SERIAL_RXCTRL_RXEN_SHIFT 0
7945c054d0SPaul Walmsley #define SIFIVE_SERIAL_RXCTRL_RXEN_MASK (1 << SIFIVE_SERIAL_RXCTRL_RXEN_SHIFT)
8045c054d0SPaul Walmsley
8145c054d0SPaul Walmsley /* IE */
8245c054d0SPaul Walmsley #define SIFIVE_SERIAL_IE_OFFS 0x10
8345c054d0SPaul Walmsley #define SIFIVE_SERIAL_IE_RXWM_SHIFT 1
8445c054d0SPaul Walmsley #define SIFIVE_SERIAL_IE_RXWM_MASK (1 << SIFIVE_SERIAL_IE_RXWM_SHIFT)
8545c054d0SPaul Walmsley #define SIFIVE_SERIAL_IE_TXWM_SHIFT 0
8645c054d0SPaul Walmsley #define SIFIVE_SERIAL_IE_TXWM_MASK (1 << SIFIVE_SERIAL_IE_TXWM_SHIFT)
8745c054d0SPaul Walmsley
8845c054d0SPaul Walmsley /* IP */
8945c054d0SPaul Walmsley #define SIFIVE_SERIAL_IP_OFFS 0x14
9045c054d0SPaul Walmsley #define SIFIVE_SERIAL_IP_RXWM_SHIFT 1
9145c054d0SPaul Walmsley #define SIFIVE_SERIAL_IP_RXWM_MASK (1 << SIFIVE_SERIAL_IP_RXWM_SHIFT)
9245c054d0SPaul Walmsley #define SIFIVE_SERIAL_IP_TXWM_SHIFT 0
9345c054d0SPaul Walmsley #define SIFIVE_SERIAL_IP_TXWM_MASK (1 << SIFIVE_SERIAL_IP_TXWM_SHIFT)
9445c054d0SPaul Walmsley
9545c054d0SPaul Walmsley /* DIV */
9645c054d0SPaul Walmsley #define SIFIVE_SERIAL_DIV_OFFS 0x18
9745c054d0SPaul Walmsley #define SIFIVE_SERIAL_DIV_DIV_SHIFT 0
9845c054d0SPaul Walmsley #define SIFIVE_SERIAL_DIV_DIV_MASK (0xffff << SIFIVE_SERIAL_IP_DIV_SHIFT)
9945c054d0SPaul Walmsley
10045c054d0SPaul Walmsley /*
10145c054d0SPaul Walmsley * Config macros
10245c054d0SPaul Walmsley */
10345c054d0SPaul Walmsley
10445c054d0SPaul Walmsley /*
10545c054d0SPaul Walmsley * SIFIVE_SERIAL_MAX_PORTS: maximum number of UARTs on a device that can
10645c054d0SPaul Walmsley * host a serial console
10745c054d0SPaul Walmsley */
10845c054d0SPaul Walmsley #define SIFIVE_SERIAL_MAX_PORTS 8
10945c054d0SPaul Walmsley
11045c054d0SPaul Walmsley /*
11145c054d0SPaul Walmsley * SIFIVE_DEFAULT_BAUD_RATE: default baud rate that the driver should
11245c054d0SPaul Walmsley * configure itself to use
11345c054d0SPaul Walmsley */
11445c054d0SPaul Walmsley #define SIFIVE_DEFAULT_BAUD_RATE 115200
11545c054d0SPaul Walmsley
11645c054d0SPaul Walmsley /* SIFIVE_SERIAL_NAME: our driver's name that we pass to the operating system */
11745c054d0SPaul Walmsley #define SIFIVE_SERIAL_NAME "sifive-serial"
11845c054d0SPaul Walmsley
11945c054d0SPaul Walmsley /* SIFIVE_TTY_PREFIX: tty name prefix for SiFive serial ports */
12045c054d0SPaul Walmsley #define SIFIVE_TTY_PREFIX "ttySIF"
12145c054d0SPaul Walmsley
12245c054d0SPaul Walmsley /* SIFIVE_TX_FIFO_DEPTH: depth of the TX FIFO (in bytes) */
12345c054d0SPaul Walmsley #define SIFIVE_TX_FIFO_DEPTH 8
12445c054d0SPaul Walmsley
12545c054d0SPaul Walmsley /* SIFIVE_RX_FIFO_DEPTH: depth of the TX FIFO (in bytes) */
12645c054d0SPaul Walmsley #define SIFIVE_RX_FIFO_DEPTH 8
12745c054d0SPaul Walmsley
12845c054d0SPaul Walmsley #if (SIFIVE_TX_FIFO_DEPTH != SIFIVE_RX_FIFO_DEPTH)
12945c054d0SPaul Walmsley #error Driver does not support configurations with different TX, RX FIFO sizes
13045c054d0SPaul Walmsley #endif
13145c054d0SPaul Walmsley
13245c054d0SPaul Walmsley /*
13345c054d0SPaul Walmsley *
13445c054d0SPaul Walmsley */
13545c054d0SPaul Walmsley
13645c054d0SPaul Walmsley /**
137180bb243SLee Jones * struct sifive_serial_port - driver-specific data extension to struct uart_port
13845c054d0SPaul Walmsley * @port: struct uart_port embedded in this struct
13945c054d0SPaul Walmsley * @dev: struct device *
14045c054d0SPaul Walmsley * @ier: shadowed copy of the interrupt enable register
14145c054d0SPaul Walmsley * @baud_rate: UART serial line rate (e.g., 115200 baud)
142180bb243SLee Jones * @clk: reference to this device's clock
14345c054d0SPaul Walmsley * @clk_notifier: clock rate change notifier for upstream clock changes
14445c054d0SPaul Walmsley *
14545c054d0SPaul Walmsley * Configuration data specific to this SiFive UART.
14645c054d0SPaul Walmsley */
14745c054d0SPaul Walmsley struct sifive_serial_port {
14845c054d0SPaul Walmsley struct uart_port port;
14945c054d0SPaul Walmsley struct device *dev;
15045c054d0SPaul Walmsley unsigned char ier;
15145c054d0SPaul Walmsley unsigned long baud_rate;
15245c054d0SPaul Walmsley struct clk *clk;
15345c054d0SPaul Walmsley struct notifier_block clk_notifier;
15445c054d0SPaul Walmsley };
15545c054d0SPaul Walmsley
15645c054d0SPaul Walmsley /*
15745c054d0SPaul Walmsley * Structure container-of macros
15845c054d0SPaul Walmsley */
15945c054d0SPaul Walmsley
16045c054d0SPaul Walmsley #define port_to_sifive_serial_port(p) (container_of((p), \
16145c054d0SPaul Walmsley struct sifive_serial_port, \
16245c054d0SPaul Walmsley port))
16345c054d0SPaul Walmsley
16445c054d0SPaul Walmsley #define notifier_to_sifive_serial_port(nb) (container_of((nb), \
16545c054d0SPaul Walmsley struct sifive_serial_port, \
16645c054d0SPaul Walmsley clk_notifier))
16745c054d0SPaul Walmsley
16845c054d0SPaul Walmsley /*
16945c054d0SPaul Walmsley * Forward declarations
17045c054d0SPaul Walmsley */
17145c054d0SPaul Walmsley static void sifive_serial_stop_tx(struct uart_port *port);
17245c054d0SPaul Walmsley
17345c054d0SPaul Walmsley /*
17445c054d0SPaul Walmsley * Internal functions
17545c054d0SPaul Walmsley */
17645c054d0SPaul Walmsley
17745c054d0SPaul Walmsley /**
17845c054d0SPaul Walmsley * __ssp_early_writel() - write to a SiFive serial port register (early)
17945c054d0SPaul Walmsley * @port: pointer to a struct uart_port record
18045c054d0SPaul Walmsley * @offs: register address offset from the IP block base address
18145c054d0SPaul Walmsley * @v: value to write to the register
18245c054d0SPaul Walmsley *
18345c054d0SPaul Walmsley * Given a pointer @port to a struct uart_port record, write the value
18445c054d0SPaul Walmsley * @v to the IP block register address offset @offs. This function is
18545c054d0SPaul Walmsley * intended for early console use.
18645c054d0SPaul Walmsley *
18745c054d0SPaul Walmsley * Context: Intended to be used only by the earlyconsole code.
18845c054d0SPaul Walmsley */
__ssp_early_writel(u32 v,u16 offs,struct uart_port * port)18945c054d0SPaul Walmsley static void __ssp_early_writel(u32 v, u16 offs, struct uart_port *port)
19045c054d0SPaul Walmsley {
19145c054d0SPaul Walmsley writel_relaxed(v, port->membase + offs);
19245c054d0SPaul Walmsley }
19345c054d0SPaul Walmsley
19445c054d0SPaul Walmsley /**
19545c054d0SPaul Walmsley * __ssp_early_readl() - read from a SiFive serial port register (early)
19645c054d0SPaul Walmsley * @port: pointer to a struct uart_port record
19745c054d0SPaul Walmsley * @offs: register address offset from the IP block base address
19845c054d0SPaul Walmsley *
19945c054d0SPaul Walmsley * Given a pointer @port to a struct uart_port record, read the
20045c054d0SPaul Walmsley * contents of the IP block register located at offset @offs from the
20145c054d0SPaul Walmsley * IP block base and return it. This function is intended for early
20245c054d0SPaul Walmsley * console use.
20345c054d0SPaul Walmsley *
20445c054d0SPaul Walmsley * Context: Intended to be called only by the earlyconsole code or by
20545c054d0SPaul Walmsley * __ssp_readl() or __ssp_writel() (in this driver)
20645c054d0SPaul Walmsley *
20745c054d0SPaul Walmsley * Returns: the register value read from the UART.
20845c054d0SPaul Walmsley */
__ssp_early_readl(struct uart_port * port,u16 offs)20945c054d0SPaul Walmsley static u32 __ssp_early_readl(struct uart_port *port, u16 offs)
21045c054d0SPaul Walmsley {
21145c054d0SPaul Walmsley return readl_relaxed(port->membase + offs);
21245c054d0SPaul Walmsley }
21345c054d0SPaul Walmsley
21445c054d0SPaul Walmsley /**
21545c054d0SPaul Walmsley * __ssp_writel() - write to a SiFive serial port register
21645c054d0SPaul Walmsley * @v: value to write to the register
21745c054d0SPaul Walmsley * @offs: register address offset from the IP block base address
21845c054d0SPaul Walmsley * @ssp: pointer to a struct sifive_serial_port record
21945c054d0SPaul Walmsley *
22045c054d0SPaul Walmsley * Write the value @v to the IP block register located at offset @offs from the
22145c054d0SPaul Walmsley * IP block base, given a pointer @ssp to a struct sifive_serial_port record.
22245c054d0SPaul Walmsley *
22345c054d0SPaul Walmsley * Context: Any context.
22445c054d0SPaul Walmsley */
__ssp_writel(u32 v,u16 offs,struct sifive_serial_port * ssp)22545c054d0SPaul Walmsley static void __ssp_writel(u32 v, u16 offs, struct sifive_serial_port *ssp)
22645c054d0SPaul Walmsley {
22745c054d0SPaul Walmsley __ssp_early_writel(v, offs, &ssp->port);
22845c054d0SPaul Walmsley }
22945c054d0SPaul Walmsley
23045c054d0SPaul Walmsley /**
23145c054d0SPaul Walmsley * __ssp_readl() - read from a SiFive serial port register
23245c054d0SPaul Walmsley * @ssp: pointer to a struct sifive_serial_port record
23345c054d0SPaul Walmsley * @offs: register address offset from the IP block base address
23445c054d0SPaul Walmsley *
23545c054d0SPaul Walmsley * Read the contents of the IP block register located at offset @offs from the
23645c054d0SPaul Walmsley * IP block base, given a pointer @ssp to a struct sifive_serial_port record.
23745c054d0SPaul Walmsley *
23845c054d0SPaul Walmsley * Context: Any context.
23945c054d0SPaul Walmsley *
24045c054d0SPaul Walmsley * Returns: the value of the UART register
24145c054d0SPaul Walmsley */
__ssp_readl(struct sifive_serial_port * ssp,u16 offs)24245c054d0SPaul Walmsley static u32 __ssp_readl(struct sifive_serial_port *ssp, u16 offs)
24345c054d0SPaul Walmsley {
24445c054d0SPaul Walmsley return __ssp_early_readl(&ssp->port, offs);
24545c054d0SPaul Walmsley }
24645c054d0SPaul Walmsley
24745c054d0SPaul Walmsley /**
24845c054d0SPaul Walmsley * sifive_serial_is_txfifo_full() - is the TXFIFO full?
24945c054d0SPaul Walmsley * @ssp: pointer to a struct sifive_serial_port
25045c054d0SPaul Walmsley *
25145c054d0SPaul Walmsley * Read the transmit FIFO "full" bit, returning a non-zero value if the
25245c054d0SPaul Walmsley * TX FIFO is full, or zero if space remains. Intended to be used to prevent
25345c054d0SPaul Walmsley * writes to the TX FIFO when it's full.
25445c054d0SPaul Walmsley *
25545c054d0SPaul Walmsley * Returns: SIFIVE_SERIAL_TXDATA_FULL_MASK (non-zero) if the transmit FIFO
25645c054d0SPaul Walmsley * is full, or 0 if space remains.
25745c054d0SPaul Walmsley */
sifive_serial_is_txfifo_full(struct sifive_serial_port * ssp)25845c054d0SPaul Walmsley static int sifive_serial_is_txfifo_full(struct sifive_serial_port *ssp)
25945c054d0SPaul Walmsley {
26045c054d0SPaul Walmsley return __ssp_readl(ssp, SIFIVE_SERIAL_TXDATA_OFFS) &
26145c054d0SPaul Walmsley SIFIVE_SERIAL_TXDATA_FULL_MASK;
26245c054d0SPaul Walmsley }
26345c054d0SPaul Walmsley
26445c054d0SPaul Walmsley /**
26545c054d0SPaul Walmsley * __ssp_transmit_char() - enqueue a byte to transmit onto the TX FIFO
26645c054d0SPaul Walmsley * @ssp: pointer to a struct sifive_serial_port
26745c054d0SPaul Walmsley * @ch: character to transmit
26845c054d0SPaul Walmsley *
26945c054d0SPaul Walmsley * Enqueue a byte @ch onto the transmit FIFO, given a pointer @ssp to the
27045c054d0SPaul Walmsley * struct sifive_serial_port * to transmit on. Caller should first check to
27145c054d0SPaul Walmsley * ensure that the TXFIFO has space; see sifive_serial_is_txfifo_full().
27245c054d0SPaul Walmsley *
27345c054d0SPaul Walmsley * Context: Any context.
27445c054d0SPaul Walmsley */
__ssp_transmit_char(struct sifive_serial_port * ssp,int ch)27545c054d0SPaul Walmsley static void __ssp_transmit_char(struct sifive_serial_port *ssp, int ch)
27645c054d0SPaul Walmsley {
27745c054d0SPaul Walmsley __ssp_writel(ch, SIFIVE_SERIAL_TXDATA_OFFS, ssp);
27845c054d0SPaul Walmsley }
27945c054d0SPaul Walmsley
28045c054d0SPaul Walmsley /**
28145c054d0SPaul Walmsley * __ssp_transmit_chars() - enqueue multiple bytes onto the TX FIFO
28245c054d0SPaul Walmsley * @ssp: pointer to a struct sifive_serial_port
28345c054d0SPaul Walmsley *
28445c054d0SPaul Walmsley * Transfer up to a TX FIFO size's worth of characters from the Linux serial
28545c054d0SPaul Walmsley * transmit buffer to the SiFive UART TX FIFO.
28645c054d0SPaul Walmsley *
28745c054d0SPaul Walmsley * Context: Any context. Expects @ssp->port.lock to be held by caller.
28845c054d0SPaul Walmsley */
__ssp_transmit_chars(struct sifive_serial_port * ssp)28945c054d0SPaul Walmsley static void __ssp_transmit_chars(struct sifive_serial_port *ssp)
29045c054d0SPaul Walmsley {
291d11cc8c3SJiri Slaby (SUSE) u8 ch;
29245c054d0SPaul Walmsley
293d11cc8c3SJiri Slaby (SUSE) uart_port_tx_limited(&ssp->port, ch, SIFIVE_TX_FIFO_DEPTH,
294d11cc8c3SJiri Slaby (SUSE) true,
295d11cc8c3SJiri Slaby (SUSE) __ssp_transmit_char(ssp, ch),
296d11cc8c3SJiri Slaby (SUSE) ({}));
29745c054d0SPaul Walmsley }
29845c054d0SPaul Walmsley
29945c054d0SPaul Walmsley /**
30045c054d0SPaul Walmsley * __ssp_enable_txwm() - enable transmit watermark interrupts
30145c054d0SPaul Walmsley * @ssp: pointer to a struct sifive_serial_port
30245c054d0SPaul Walmsley *
30345c054d0SPaul Walmsley * Enable interrupt generation when the transmit FIFO watermark is reached
30445c054d0SPaul Walmsley * on the SiFive UART referred to by @ssp.
30545c054d0SPaul Walmsley */
__ssp_enable_txwm(struct sifive_serial_port * ssp)30645c054d0SPaul Walmsley static void __ssp_enable_txwm(struct sifive_serial_port *ssp)
30745c054d0SPaul Walmsley {
30845c054d0SPaul Walmsley if (ssp->ier & SIFIVE_SERIAL_IE_TXWM_MASK)
30945c054d0SPaul Walmsley return;
31045c054d0SPaul Walmsley
31145c054d0SPaul Walmsley ssp->ier |= SIFIVE_SERIAL_IE_TXWM_MASK;
31245c054d0SPaul Walmsley __ssp_writel(ssp->ier, SIFIVE_SERIAL_IE_OFFS, ssp);
31345c054d0SPaul Walmsley }
31445c054d0SPaul Walmsley
31545c054d0SPaul Walmsley /**
31645c054d0SPaul Walmsley * __ssp_enable_rxwm() - enable receive watermark interrupts
31745c054d0SPaul Walmsley * @ssp: pointer to a struct sifive_serial_port
31845c054d0SPaul Walmsley *
31945c054d0SPaul Walmsley * Enable interrupt generation when the receive FIFO watermark is reached
32045c054d0SPaul Walmsley * on the SiFive UART referred to by @ssp.
32145c054d0SPaul Walmsley */
__ssp_enable_rxwm(struct sifive_serial_port * ssp)32245c054d0SPaul Walmsley static void __ssp_enable_rxwm(struct sifive_serial_port *ssp)
32345c054d0SPaul Walmsley {
32445c054d0SPaul Walmsley if (ssp->ier & SIFIVE_SERIAL_IE_RXWM_MASK)
32545c054d0SPaul Walmsley return;
32645c054d0SPaul Walmsley
32745c054d0SPaul Walmsley ssp->ier |= SIFIVE_SERIAL_IE_RXWM_MASK;
32845c054d0SPaul Walmsley __ssp_writel(ssp->ier, SIFIVE_SERIAL_IE_OFFS, ssp);
32945c054d0SPaul Walmsley }
33045c054d0SPaul Walmsley
33145c054d0SPaul Walmsley /**
33245c054d0SPaul Walmsley * __ssp_disable_txwm() - disable transmit watermark interrupts
33345c054d0SPaul Walmsley * @ssp: pointer to a struct sifive_serial_port
33445c054d0SPaul Walmsley *
33545c054d0SPaul Walmsley * Disable interrupt generation when the transmit FIFO watermark is reached
33645c054d0SPaul Walmsley * on the UART referred to by @ssp.
33745c054d0SPaul Walmsley */
__ssp_disable_txwm(struct sifive_serial_port * ssp)33845c054d0SPaul Walmsley static void __ssp_disable_txwm(struct sifive_serial_port *ssp)
33945c054d0SPaul Walmsley {
34045c054d0SPaul Walmsley if (!(ssp->ier & SIFIVE_SERIAL_IE_TXWM_MASK))
34145c054d0SPaul Walmsley return;
34245c054d0SPaul Walmsley
34345c054d0SPaul Walmsley ssp->ier &= ~SIFIVE_SERIAL_IE_TXWM_MASK;
34445c054d0SPaul Walmsley __ssp_writel(ssp->ier, SIFIVE_SERIAL_IE_OFFS, ssp);
34545c054d0SPaul Walmsley }
34645c054d0SPaul Walmsley
34745c054d0SPaul Walmsley /**
34845c054d0SPaul Walmsley * __ssp_disable_rxwm() - disable receive watermark interrupts
34945c054d0SPaul Walmsley * @ssp: pointer to a struct sifive_serial_port
35045c054d0SPaul Walmsley *
35145c054d0SPaul Walmsley * Disable interrupt generation when the receive FIFO watermark is reached
35245c054d0SPaul Walmsley * on the UART referred to by @ssp.
35345c054d0SPaul Walmsley */
__ssp_disable_rxwm(struct sifive_serial_port * ssp)35445c054d0SPaul Walmsley static void __ssp_disable_rxwm(struct sifive_serial_port *ssp)
35545c054d0SPaul Walmsley {
35645c054d0SPaul Walmsley if (!(ssp->ier & SIFIVE_SERIAL_IE_RXWM_MASK))
35745c054d0SPaul Walmsley return;
35845c054d0SPaul Walmsley
35945c054d0SPaul Walmsley ssp->ier &= ~SIFIVE_SERIAL_IE_RXWM_MASK;
36045c054d0SPaul Walmsley __ssp_writel(ssp->ier, SIFIVE_SERIAL_IE_OFFS, ssp);
36145c054d0SPaul Walmsley }
36245c054d0SPaul Walmsley
36345c054d0SPaul Walmsley /**
36445c054d0SPaul Walmsley * __ssp_receive_char() - receive a byte from the UART
36545c054d0SPaul Walmsley * @ssp: pointer to a struct sifive_serial_port
36645c054d0SPaul Walmsley * @is_empty: char pointer to return whether the RX FIFO is empty
36745c054d0SPaul Walmsley *
36845c054d0SPaul Walmsley * Try to read a byte from the SiFive UART RX FIFO, referenced by
36945c054d0SPaul Walmsley * @ssp, and to return it. Also returns the RX FIFO empty bit in
37045c054d0SPaul Walmsley * the char pointed to by @ch. The caller must pass the byte back to the
37145c054d0SPaul Walmsley * Linux serial layer if needed.
37245c054d0SPaul Walmsley *
37345c054d0SPaul Walmsley * Returns: the byte read from the UART RX FIFO.
37445c054d0SPaul Walmsley */
__ssp_receive_char(struct sifive_serial_port * ssp,char * is_empty)37545c054d0SPaul Walmsley static char __ssp_receive_char(struct sifive_serial_port *ssp, char *is_empty)
37645c054d0SPaul Walmsley {
37745c054d0SPaul Walmsley u32 v;
37845c054d0SPaul Walmsley u8 ch;
37945c054d0SPaul Walmsley
38045c054d0SPaul Walmsley v = __ssp_readl(ssp, SIFIVE_SERIAL_RXDATA_OFFS);
38145c054d0SPaul Walmsley
38245c054d0SPaul Walmsley if (!is_empty)
38345c054d0SPaul Walmsley WARN_ON(1);
38445c054d0SPaul Walmsley else
38545c054d0SPaul Walmsley *is_empty = (v & SIFIVE_SERIAL_RXDATA_EMPTY_MASK) >>
38645c054d0SPaul Walmsley SIFIVE_SERIAL_RXDATA_EMPTY_SHIFT;
38745c054d0SPaul Walmsley
38845c054d0SPaul Walmsley ch = (v & SIFIVE_SERIAL_RXDATA_DATA_MASK) >>
38945c054d0SPaul Walmsley SIFIVE_SERIAL_RXDATA_DATA_SHIFT;
39045c054d0SPaul Walmsley
39145c054d0SPaul Walmsley return ch;
39245c054d0SPaul Walmsley }
39345c054d0SPaul Walmsley
39445c054d0SPaul Walmsley /**
39545c054d0SPaul Walmsley * __ssp_receive_chars() - receive multiple bytes from the UART
39645c054d0SPaul Walmsley * @ssp: pointer to a struct sifive_serial_port
39745c054d0SPaul Walmsley *
39845c054d0SPaul Walmsley * Receive up to an RX FIFO's worth of bytes from the SiFive UART referred
39945c054d0SPaul Walmsley * to by @ssp and pass them up to the Linux serial layer.
40045c054d0SPaul Walmsley *
40145c054d0SPaul Walmsley * Context: Expects ssp->port.lock to be held by caller.
40245c054d0SPaul Walmsley */
__ssp_receive_chars(struct sifive_serial_port * ssp)40345c054d0SPaul Walmsley static void __ssp_receive_chars(struct sifive_serial_port *ssp)
40445c054d0SPaul Walmsley {
40545c054d0SPaul Walmsley char is_empty;
40645c054d0SPaul Walmsley int c;
407fd2b55f8SJiri Slaby u8 ch;
40845c054d0SPaul Walmsley
40945c054d0SPaul Walmsley for (c = SIFIVE_RX_FIFO_DEPTH; c > 0; --c) {
41045c054d0SPaul Walmsley ch = __ssp_receive_char(ssp, &is_empty);
41145c054d0SPaul Walmsley if (is_empty)
41245c054d0SPaul Walmsley break;
41345c054d0SPaul Walmsley
41445c054d0SPaul Walmsley ssp->port.icount.rx++;
41532c694ecSSebastian Andrzej Siewior if (!uart_prepare_sysrq_char(&ssp->port, ch))
41645c054d0SPaul Walmsley uart_insert_char(&ssp->port, 0, 0, ch, TTY_NORMAL);
41745c054d0SPaul Walmsley }
41845c054d0SPaul Walmsley
41945c054d0SPaul Walmsley tty_flip_buffer_push(&ssp->port.state->port);
42045c054d0SPaul Walmsley }
42145c054d0SPaul Walmsley
42245c054d0SPaul Walmsley /**
42345c054d0SPaul Walmsley * __ssp_update_div() - calculate the divisor setting by the line rate
42445c054d0SPaul Walmsley * @ssp: pointer to a struct sifive_serial_port
42545c054d0SPaul Walmsley *
42645c054d0SPaul Walmsley * Calculate the appropriate value of the clock divisor for the UART
42745c054d0SPaul Walmsley * and target line rate referred to by @ssp and write it into the
42845c054d0SPaul Walmsley * hardware.
42945c054d0SPaul Walmsley */
__ssp_update_div(struct sifive_serial_port * ssp)43045c054d0SPaul Walmsley static void __ssp_update_div(struct sifive_serial_port *ssp)
43145c054d0SPaul Walmsley {
43245c054d0SPaul Walmsley u16 div;
43345c054d0SPaul Walmsley
4344487cd3eSMaciej W. Rozycki div = DIV_ROUND_UP(ssp->port.uartclk, ssp->baud_rate) - 1;
43545c054d0SPaul Walmsley
43645c054d0SPaul Walmsley __ssp_writel(div, SIFIVE_SERIAL_DIV_OFFS, ssp);
43745c054d0SPaul Walmsley }
43845c054d0SPaul Walmsley
43945c054d0SPaul Walmsley /**
44045c054d0SPaul Walmsley * __ssp_update_baud_rate() - set the UART "baud rate"
44145c054d0SPaul Walmsley * @ssp: pointer to a struct sifive_serial_port
44245c054d0SPaul Walmsley * @rate: new target bit rate
44345c054d0SPaul Walmsley *
44445c054d0SPaul Walmsley * Calculate the UART divisor value for the target bit rate @rate for the
44545c054d0SPaul Walmsley * SiFive UART described by @ssp and program it into the UART. There may
44645c054d0SPaul Walmsley * be some error between the target bit rate and the actual bit rate implemented
44745c054d0SPaul Walmsley * by the UART due to clock ratio granularity.
44845c054d0SPaul Walmsley */
__ssp_update_baud_rate(struct sifive_serial_port * ssp,unsigned int rate)44945c054d0SPaul Walmsley static void __ssp_update_baud_rate(struct sifive_serial_port *ssp,
45045c054d0SPaul Walmsley unsigned int rate)
45145c054d0SPaul Walmsley {
45245c054d0SPaul Walmsley if (ssp->baud_rate == rate)
45345c054d0SPaul Walmsley return;
45445c054d0SPaul Walmsley
45545c054d0SPaul Walmsley ssp->baud_rate = rate;
45645c054d0SPaul Walmsley __ssp_update_div(ssp);
45745c054d0SPaul Walmsley }
45845c054d0SPaul Walmsley
45945c054d0SPaul Walmsley /**
46045c054d0SPaul Walmsley * __ssp_set_stop_bits() - set the number of stop bits
46145c054d0SPaul Walmsley * @ssp: pointer to a struct sifive_serial_port
46245c054d0SPaul Walmsley * @nstop: 1 or 2 (stop bits)
46345c054d0SPaul Walmsley *
46445c054d0SPaul Walmsley * Program the SiFive UART referred to by @ssp to use @nstop stop bits.
46545c054d0SPaul Walmsley */
__ssp_set_stop_bits(struct sifive_serial_port * ssp,char nstop)46645c054d0SPaul Walmsley static void __ssp_set_stop_bits(struct sifive_serial_port *ssp, char nstop)
46745c054d0SPaul Walmsley {
46845c054d0SPaul Walmsley u32 v;
46945c054d0SPaul Walmsley
47045c054d0SPaul Walmsley if (nstop < 1 || nstop > 2) {
47145c054d0SPaul Walmsley WARN_ON(1);
47245c054d0SPaul Walmsley return;
47345c054d0SPaul Walmsley }
47445c054d0SPaul Walmsley
47545c054d0SPaul Walmsley v = __ssp_readl(ssp, SIFIVE_SERIAL_TXCTRL_OFFS);
47645c054d0SPaul Walmsley v &= ~SIFIVE_SERIAL_TXCTRL_NSTOP_MASK;
47745c054d0SPaul Walmsley v |= (nstop - 1) << SIFIVE_SERIAL_TXCTRL_NSTOP_SHIFT;
47845c054d0SPaul Walmsley __ssp_writel(v, SIFIVE_SERIAL_TXCTRL_OFFS, ssp);
47945c054d0SPaul Walmsley }
48045c054d0SPaul Walmsley
48145c054d0SPaul Walmsley /**
48245c054d0SPaul Walmsley * __ssp_wait_for_xmitr() - wait for an empty slot on the TX FIFO
48345c054d0SPaul Walmsley * @ssp: pointer to a struct sifive_serial_port
48445c054d0SPaul Walmsley *
48545c054d0SPaul Walmsley * Delay while the UART TX FIFO referred to by @ssp is marked as full.
48645c054d0SPaul Walmsley *
48745c054d0SPaul Walmsley * Context: Any context.
48845c054d0SPaul Walmsley */
__ssp_wait_for_xmitr(struct sifive_serial_port * ssp)48945c054d0SPaul Walmsley static void __maybe_unused __ssp_wait_for_xmitr(struct sifive_serial_port *ssp)
49045c054d0SPaul Walmsley {
49145c054d0SPaul Walmsley while (sifive_serial_is_txfifo_full(ssp))
49245c054d0SPaul Walmsley udelay(1); /* XXX Could probably be more intelligent here */
49345c054d0SPaul Walmsley }
49445c054d0SPaul Walmsley
49545c054d0SPaul Walmsley /*
49645c054d0SPaul Walmsley * Linux serial API functions
49745c054d0SPaul Walmsley */
49845c054d0SPaul Walmsley
sifive_serial_stop_tx(struct uart_port * port)49945c054d0SPaul Walmsley static void sifive_serial_stop_tx(struct uart_port *port)
50045c054d0SPaul Walmsley {
50145c054d0SPaul Walmsley struct sifive_serial_port *ssp = port_to_sifive_serial_port(port);
50245c054d0SPaul Walmsley
50345c054d0SPaul Walmsley __ssp_disable_txwm(ssp);
50445c054d0SPaul Walmsley }
50545c054d0SPaul Walmsley
sifive_serial_stop_rx(struct uart_port * port)50645c054d0SPaul Walmsley static void sifive_serial_stop_rx(struct uart_port *port)
50745c054d0SPaul Walmsley {
50845c054d0SPaul Walmsley struct sifive_serial_port *ssp = port_to_sifive_serial_port(port);
50945c054d0SPaul Walmsley
51045c054d0SPaul Walmsley __ssp_disable_rxwm(ssp);
51145c054d0SPaul Walmsley }
51245c054d0SPaul Walmsley
sifive_serial_start_tx(struct uart_port * port)51345c054d0SPaul Walmsley static void sifive_serial_start_tx(struct uart_port *port)
51445c054d0SPaul Walmsley {
51545c054d0SPaul Walmsley struct sifive_serial_port *ssp = port_to_sifive_serial_port(port);
51645c054d0SPaul Walmsley
51745c054d0SPaul Walmsley __ssp_enable_txwm(ssp);
51845c054d0SPaul Walmsley }
51945c054d0SPaul Walmsley
sifive_serial_irq(int irq,void * dev_id)52045c054d0SPaul Walmsley static irqreturn_t sifive_serial_irq(int irq, void *dev_id)
52145c054d0SPaul Walmsley {
52245c054d0SPaul Walmsley struct sifive_serial_port *ssp = dev_id;
52345c054d0SPaul Walmsley u32 ip;
52445c054d0SPaul Walmsley
52593614effSThomas Gleixner uart_port_lock(&ssp->port);
52645c054d0SPaul Walmsley
52745c054d0SPaul Walmsley ip = __ssp_readl(ssp, SIFIVE_SERIAL_IP_OFFS);
52845c054d0SPaul Walmsley if (!ip) {
52993614effSThomas Gleixner uart_port_unlock(&ssp->port);
53045c054d0SPaul Walmsley return IRQ_NONE;
53145c054d0SPaul Walmsley }
53245c054d0SPaul Walmsley
53345c054d0SPaul Walmsley if (ip & SIFIVE_SERIAL_IP_RXWM_MASK)
53445c054d0SPaul Walmsley __ssp_receive_chars(ssp);
53545c054d0SPaul Walmsley if (ip & SIFIVE_SERIAL_IP_TXWM_MASK)
53645c054d0SPaul Walmsley __ssp_transmit_chars(ssp);
53745c054d0SPaul Walmsley
53832c694ecSSebastian Andrzej Siewior uart_unlock_and_check_sysrq(&ssp->port);
53945c054d0SPaul Walmsley
54045c054d0SPaul Walmsley return IRQ_HANDLED;
54145c054d0SPaul Walmsley }
54245c054d0SPaul Walmsley
sifive_serial_tx_empty(struct uart_port * port)54345c054d0SPaul Walmsley static unsigned int sifive_serial_tx_empty(struct uart_port *port)
54445c054d0SPaul Walmsley {
54545c054d0SPaul Walmsley return TIOCSER_TEMT;
54645c054d0SPaul Walmsley }
54745c054d0SPaul Walmsley
sifive_serial_get_mctrl(struct uart_port * port)54845c054d0SPaul Walmsley static unsigned int sifive_serial_get_mctrl(struct uart_port *port)
54945c054d0SPaul Walmsley {
55045c054d0SPaul Walmsley return TIOCM_CAR | TIOCM_CTS | TIOCM_DSR;
55145c054d0SPaul Walmsley }
55245c054d0SPaul Walmsley
sifive_serial_set_mctrl(struct uart_port * port,unsigned int mctrl)55345c054d0SPaul Walmsley static void sifive_serial_set_mctrl(struct uart_port *port, unsigned int mctrl)
55445c054d0SPaul Walmsley {
55545c054d0SPaul Walmsley /* IP block does not support these signals */
55645c054d0SPaul Walmsley }
55745c054d0SPaul Walmsley
sifive_serial_break_ctl(struct uart_port * port,int break_state)55845c054d0SPaul Walmsley static void sifive_serial_break_ctl(struct uart_port *port, int break_state)
55945c054d0SPaul Walmsley {
56045c054d0SPaul Walmsley /* IP block does not support sending a break */
56145c054d0SPaul Walmsley }
56245c054d0SPaul Walmsley
sifive_serial_startup(struct uart_port * port)56345c054d0SPaul Walmsley static int sifive_serial_startup(struct uart_port *port)
56445c054d0SPaul Walmsley {
56545c054d0SPaul Walmsley struct sifive_serial_port *ssp = port_to_sifive_serial_port(port);
56645c054d0SPaul Walmsley
56745c054d0SPaul Walmsley __ssp_enable_rxwm(ssp);
56845c054d0SPaul Walmsley
56945c054d0SPaul Walmsley return 0;
57045c054d0SPaul Walmsley }
57145c054d0SPaul Walmsley
sifive_serial_shutdown(struct uart_port * port)57245c054d0SPaul Walmsley static void sifive_serial_shutdown(struct uart_port *port)
57345c054d0SPaul Walmsley {
57445c054d0SPaul Walmsley struct sifive_serial_port *ssp = port_to_sifive_serial_port(port);
57545c054d0SPaul Walmsley
57645c054d0SPaul Walmsley __ssp_disable_rxwm(ssp);
57745c054d0SPaul Walmsley __ssp_disable_txwm(ssp);
57845c054d0SPaul Walmsley }
57945c054d0SPaul Walmsley
58045c054d0SPaul Walmsley /**
58145c054d0SPaul Walmsley * sifive_serial_clk_notifier() - clock post-rate-change notifier
58245c054d0SPaul Walmsley * @nb: pointer to the struct notifier_block, from the notifier code
58345c054d0SPaul Walmsley * @event: event mask from the notifier code
58445c054d0SPaul Walmsley * @data: pointer to the struct clk_notifier_data from the notifier code
58545c054d0SPaul Walmsley *
58645c054d0SPaul Walmsley * On the V0 SoC, the UART IP block is derived from the CPU clock source
58745c054d0SPaul Walmsley * after a synchronous divide-by-two divider, so any CPU clock rate change
5884cbd7814SPalmer Dabbelt * requires the UART baud rate to be updated. This presumably corrupts any
5894cbd7814SPalmer Dabbelt * serial word currently being transmitted or received. In order to avoid
5904cbd7814SPalmer Dabbelt * corrupting the output data stream, we drain the transmit queue before
5914cbd7814SPalmer Dabbelt * allowing the clock's rate to be changed.
59245c054d0SPaul Walmsley */
sifive_serial_clk_notifier(struct notifier_block * nb,unsigned long event,void * data)59345c054d0SPaul Walmsley static int sifive_serial_clk_notifier(struct notifier_block *nb,
59445c054d0SPaul Walmsley unsigned long event, void *data)
59545c054d0SPaul Walmsley {
59645c054d0SPaul Walmsley struct clk_notifier_data *cnd = data;
59745c054d0SPaul Walmsley struct sifive_serial_port *ssp = notifier_to_sifive_serial_port(nb);
59845c054d0SPaul Walmsley
5994cbd7814SPalmer Dabbelt if (event == PRE_RATE_CHANGE) {
6004cbd7814SPalmer Dabbelt /*
6014cbd7814SPalmer Dabbelt * The TX watermark is always set to 1 by this driver, which
6024cbd7814SPalmer Dabbelt * means that the TX busy bit will lower when there are 0 bytes
6034cbd7814SPalmer Dabbelt * left in the TX queue -- in other words, when the TX FIFO is
6044cbd7814SPalmer Dabbelt * empty.
6054cbd7814SPalmer Dabbelt */
6064cbd7814SPalmer Dabbelt __ssp_wait_for_xmitr(ssp);
6074cbd7814SPalmer Dabbelt /*
6084cbd7814SPalmer Dabbelt * On the cycle the TX FIFO goes empty there is still a full
6094cbd7814SPalmer Dabbelt * UART frame left to be transmitted in the shift register.
6104cbd7814SPalmer Dabbelt * The UART provides no way for software to directly determine
6114cbd7814SPalmer Dabbelt * when that last frame has been transmitted, so we just sleep
6124cbd7814SPalmer Dabbelt * here instead. As we're not tracking the number of stop bits
6134cbd7814SPalmer Dabbelt * they're just worst cased here. The rest of the serial
6144cbd7814SPalmer Dabbelt * framing parameters aren't configurable by software.
6154cbd7814SPalmer Dabbelt */
6164cbd7814SPalmer Dabbelt udelay(DIV_ROUND_UP(12 * 1000 * 1000, ssp->baud_rate));
6174cbd7814SPalmer Dabbelt }
6184cbd7814SPalmer Dabbelt
6194487cd3eSMaciej W. Rozycki if (event == POST_RATE_CHANGE && ssp->port.uartclk != cnd->new_rate) {
6204487cd3eSMaciej W. Rozycki ssp->port.uartclk = cnd->new_rate;
62145c054d0SPaul Walmsley __ssp_update_div(ssp);
62245c054d0SPaul Walmsley }
62345c054d0SPaul Walmsley
62445c054d0SPaul Walmsley return NOTIFY_OK;
62545c054d0SPaul Walmsley }
62645c054d0SPaul Walmsley
sifive_serial_set_termios(struct uart_port * port,struct ktermios * termios,const struct ktermios * old)62745c054d0SPaul Walmsley static void sifive_serial_set_termios(struct uart_port *port,
62845c054d0SPaul Walmsley struct ktermios *termios,
629bec5b814SIlpo Järvinen const struct ktermios *old)
63045c054d0SPaul Walmsley {
63145c054d0SPaul Walmsley struct sifive_serial_port *ssp = port_to_sifive_serial_port(port);
63245c054d0SPaul Walmsley unsigned long flags;
63345c054d0SPaul Walmsley u32 v, old_v;
63445c054d0SPaul Walmsley int rate;
63545c054d0SPaul Walmsley char nstop;
63645c054d0SPaul Walmsley
637c069d275SIlpo Järvinen if ((termios->c_cflag & CSIZE) != CS8) {
63845c054d0SPaul Walmsley dev_err_once(ssp->port.dev, "only 8-bit words supported\n");
639c069d275SIlpo Järvinen termios->c_cflag &= ~CSIZE;
640c069d275SIlpo Järvinen termios->c_cflag |= CS8;
641c069d275SIlpo Järvinen }
64245c054d0SPaul Walmsley if (termios->c_iflag & (INPCK | PARMRK))
64345c054d0SPaul Walmsley dev_err_once(ssp->port.dev, "parity checking not supported\n");
64445c054d0SPaul Walmsley if (termios->c_iflag & BRKINT)
64545c054d0SPaul Walmsley dev_err_once(ssp->port.dev, "BREAK detection not supported\n");
646c069d275SIlpo Järvinen termios->c_iflag &= ~(INPCK|PARMRK|BRKINT);
64745c054d0SPaul Walmsley
64845c054d0SPaul Walmsley /* Set number of stop bits */
64945c054d0SPaul Walmsley nstop = (termios->c_cflag & CSTOPB) ? 2 : 1;
65045c054d0SPaul Walmsley __ssp_set_stop_bits(ssp, nstop);
65145c054d0SPaul Walmsley
65245c054d0SPaul Walmsley /* Set line rate */
6534487cd3eSMaciej W. Rozycki rate = uart_get_baud_rate(port, termios, old, 0,
6544487cd3eSMaciej W. Rozycki ssp->port.uartclk / 16);
65545c054d0SPaul Walmsley __ssp_update_baud_rate(ssp, rate);
65645c054d0SPaul Walmsley
65793614effSThomas Gleixner uart_port_lock_irqsave(&ssp->port, &flags);
65845c054d0SPaul Walmsley
65945c054d0SPaul Walmsley /* Update the per-port timeout */
66045c054d0SPaul Walmsley uart_update_timeout(port, termios->c_cflag, rate);
66145c054d0SPaul Walmsley
66245c054d0SPaul Walmsley ssp->port.read_status_mask = 0;
66345c054d0SPaul Walmsley
66445c054d0SPaul Walmsley /* Ignore all characters if CREAD is not set */
66545c054d0SPaul Walmsley v = __ssp_readl(ssp, SIFIVE_SERIAL_RXCTRL_OFFS);
66645c054d0SPaul Walmsley old_v = v;
66745c054d0SPaul Walmsley if ((termios->c_cflag & CREAD) == 0)
66845c054d0SPaul Walmsley v &= SIFIVE_SERIAL_RXCTRL_RXEN_MASK;
66945c054d0SPaul Walmsley else
67045c054d0SPaul Walmsley v |= SIFIVE_SERIAL_RXCTRL_RXEN_MASK;
67145c054d0SPaul Walmsley if (v != old_v)
67245c054d0SPaul Walmsley __ssp_writel(v, SIFIVE_SERIAL_RXCTRL_OFFS, ssp);
67345c054d0SPaul Walmsley
67493614effSThomas Gleixner uart_port_unlock_irqrestore(&ssp->port, flags);
67545c054d0SPaul Walmsley }
67645c054d0SPaul Walmsley
sifive_serial_release_port(struct uart_port * port)67745c054d0SPaul Walmsley static void sifive_serial_release_port(struct uart_port *port)
67845c054d0SPaul Walmsley {
67945c054d0SPaul Walmsley }
68045c054d0SPaul Walmsley
sifive_serial_request_port(struct uart_port * port)68145c054d0SPaul Walmsley static int sifive_serial_request_port(struct uart_port *port)
68245c054d0SPaul Walmsley {
68345c054d0SPaul Walmsley return 0;
68445c054d0SPaul Walmsley }
68545c054d0SPaul Walmsley
sifive_serial_config_port(struct uart_port * port,int flags)68645c054d0SPaul Walmsley static void sifive_serial_config_port(struct uart_port *port, int flags)
68745c054d0SPaul Walmsley {
68845c054d0SPaul Walmsley struct sifive_serial_port *ssp = port_to_sifive_serial_port(port);
68945c054d0SPaul Walmsley
69045c054d0SPaul Walmsley ssp->port.type = PORT_SIFIVE_V0;
69145c054d0SPaul Walmsley }
69245c054d0SPaul Walmsley
sifive_serial_verify_port(struct uart_port * port,struct serial_struct * ser)69345c054d0SPaul Walmsley static int sifive_serial_verify_port(struct uart_port *port,
69445c054d0SPaul Walmsley struct serial_struct *ser)
69545c054d0SPaul Walmsley {
69645c054d0SPaul Walmsley return -EINVAL;
69745c054d0SPaul Walmsley }
69845c054d0SPaul Walmsley
sifive_serial_type(struct uart_port * port)69945c054d0SPaul Walmsley static const char *sifive_serial_type(struct uart_port *port)
70045c054d0SPaul Walmsley {
70145c054d0SPaul Walmsley return port->type == PORT_SIFIVE_V0 ? "SiFive UART v0" : NULL;
70245c054d0SPaul Walmsley }
70345c054d0SPaul Walmsley
704630db5cbSVincent Chen #ifdef CONFIG_CONSOLE_POLL
sifive_serial_poll_get_char(struct uart_port * port)705630db5cbSVincent Chen static int sifive_serial_poll_get_char(struct uart_port *port)
706630db5cbSVincent Chen {
707630db5cbSVincent Chen struct sifive_serial_port *ssp = port_to_sifive_serial_port(port);
708630db5cbSVincent Chen char is_empty, ch;
709630db5cbSVincent Chen
710630db5cbSVincent Chen ch = __ssp_receive_char(ssp, &is_empty);
711630db5cbSVincent Chen if (is_empty)
712630db5cbSVincent Chen return NO_POLL_CHAR;
713630db5cbSVincent Chen
714630db5cbSVincent Chen return ch;
715630db5cbSVincent Chen }
716630db5cbSVincent Chen
sifive_serial_poll_put_char(struct uart_port * port,unsigned char c)717630db5cbSVincent Chen static void sifive_serial_poll_put_char(struct uart_port *port,
718630db5cbSVincent Chen unsigned char c)
719630db5cbSVincent Chen {
720630db5cbSVincent Chen struct sifive_serial_port *ssp = port_to_sifive_serial_port(port);
721630db5cbSVincent Chen
722630db5cbSVincent Chen __ssp_wait_for_xmitr(ssp);
723630db5cbSVincent Chen __ssp_transmit_char(ssp, c);
724630db5cbSVincent Chen }
725630db5cbSVincent Chen #endif /* CONFIG_CONSOLE_POLL */
726630db5cbSVincent Chen
72745c054d0SPaul Walmsley /*
72845c054d0SPaul Walmsley * Early console support
72945c054d0SPaul Walmsley */
73045c054d0SPaul Walmsley
73145c054d0SPaul Walmsley #ifdef CONFIG_SERIAL_EARLYCON
early_sifive_serial_putc(struct uart_port * port,unsigned char c)7323f8bab17SJiri Slaby static void early_sifive_serial_putc(struct uart_port *port, unsigned char c)
73345c054d0SPaul Walmsley {
73445c054d0SPaul Walmsley while (__ssp_early_readl(port, SIFIVE_SERIAL_TXDATA_OFFS) &
73545c054d0SPaul Walmsley SIFIVE_SERIAL_TXDATA_FULL_MASK)
73645c054d0SPaul Walmsley cpu_relax();
73745c054d0SPaul Walmsley
73845c054d0SPaul Walmsley __ssp_early_writel(c, SIFIVE_SERIAL_TXDATA_OFFS, port);
73945c054d0SPaul Walmsley }
74045c054d0SPaul Walmsley
early_sifive_serial_write(struct console * con,const char * s,unsigned int n)74145c054d0SPaul Walmsley static void early_sifive_serial_write(struct console *con, const char *s,
74245c054d0SPaul Walmsley unsigned int n)
74345c054d0SPaul Walmsley {
74445c054d0SPaul Walmsley struct earlycon_device *dev = con->data;
74545c054d0SPaul Walmsley struct uart_port *port = &dev->port;
74645c054d0SPaul Walmsley
74745c054d0SPaul Walmsley uart_console_write(port, s, n, early_sifive_serial_putc);
74845c054d0SPaul Walmsley }
74945c054d0SPaul Walmsley
early_sifive_serial_setup(struct earlycon_device * dev,const char * options)75045c054d0SPaul Walmsley static int __init early_sifive_serial_setup(struct earlycon_device *dev,
75145c054d0SPaul Walmsley const char *options)
75245c054d0SPaul Walmsley {
75345c054d0SPaul Walmsley struct uart_port *port = &dev->port;
75445c054d0SPaul Walmsley
75545c054d0SPaul Walmsley if (!port->membase)
75645c054d0SPaul Walmsley return -ENODEV;
75745c054d0SPaul Walmsley
75845c054d0SPaul Walmsley dev->con->write = early_sifive_serial_write;
75945c054d0SPaul Walmsley
76045c054d0SPaul Walmsley return 0;
76145c054d0SPaul Walmsley }
76245c054d0SPaul Walmsley
76345c054d0SPaul Walmsley OF_EARLYCON_DECLARE(sifive, "sifive,uart0", early_sifive_serial_setup);
76442100227SSebastian Andrzej Siewior OF_EARLYCON_DECLARE(sifive, "sifive,fu540-c000-uart",
76545c054d0SPaul Walmsley early_sifive_serial_setup);
76645c054d0SPaul Walmsley #endif /* CONFIG_SERIAL_EARLYCON */
76745c054d0SPaul Walmsley
76845c054d0SPaul Walmsley /*
76945c054d0SPaul Walmsley * Linux console interface
77045c054d0SPaul Walmsley */
77145c054d0SPaul Walmsley
77245c054d0SPaul Walmsley #ifdef CONFIG_SERIAL_SIFIVE_CONSOLE
77345c054d0SPaul Walmsley
77445c054d0SPaul Walmsley static struct sifive_serial_port *sifive_serial_console_ports[SIFIVE_SERIAL_MAX_PORTS];
77545c054d0SPaul Walmsley
sifive_serial_console_putchar(struct uart_port * port,unsigned char ch)7763f8bab17SJiri Slaby static void sifive_serial_console_putchar(struct uart_port *port, unsigned char ch)
77745c054d0SPaul Walmsley {
77845c054d0SPaul Walmsley struct sifive_serial_port *ssp = port_to_sifive_serial_port(port);
77945c054d0SPaul Walmsley
78045c054d0SPaul Walmsley __ssp_wait_for_xmitr(ssp);
78145c054d0SPaul Walmsley __ssp_transmit_char(ssp, ch);
78245c054d0SPaul Walmsley }
78345c054d0SPaul Walmsley
sifive_serial_console_write(struct console * co,const char * s,unsigned int count)78445c054d0SPaul Walmsley static void sifive_serial_console_write(struct console *co, const char *s,
78545c054d0SPaul Walmsley unsigned int count)
78645c054d0SPaul Walmsley {
78745c054d0SPaul Walmsley struct sifive_serial_port *ssp = sifive_serial_console_ports[co->index];
78845c054d0SPaul Walmsley unsigned long flags;
78945c054d0SPaul Walmsley unsigned int ier;
79045c054d0SPaul Walmsley int locked = 1;
79145c054d0SPaul Walmsley
79245c054d0SPaul Walmsley if (!ssp)
79345c054d0SPaul Walmsley return;
79445c054d0SPaul Walmsley
79532c694ecSSebastian Andrzej Siewior if (oops_in_progress)
79632c694ecSSebastian Andrzej Siewior locked = uart_port_trylock_irqsave(&ssp->port, &flags);
79745c054d0SPaul Walmsley else
79832c694ecSSebastian Andrzej Siewior uart_port_lock_irqsave(&ssp->port, &flags);
79945c054d0SPaul Walmsley
80045c054d0SPaul Walmsley ier = __ssp_readl(ssp, SIFIVE_SERIAL_IE_OFFS);
80145c054d0SPaul Walmsley __ssp_writel(0, SIFIVE_SERIAL_IE_OFFS, ssp);
80245c054d0SPaul Walmsley
80345c054d0SPaul Walmsley uart_console_write(&ssp->port, s, count, sifive_serial_console_putchar);
80445c054d0SPaul Walmsley
80545c054d0SPaul Walmsley __ssp_writel(ier, SIFIVE_SERIAL_IE_OFFS, ssp);
80645c054d0SPaul Walmsley
80745c054d0SPaul Walmsley if (locked)
80832c694ecSSebastian Andrzej Siewior uart_port_unlock_irqrestore(&ssp->port, flags);
80945c054d0SPaul Walmsley }
81045c054d0SPaul Walmsley
sifive_serial_console_setup(struct console * co,char * options)8119b8fef63SSamuel Holland static int sifive_serial_console_setup(struct console *co, char *options)
81245c054d0SPaul Walmsley {
81345c054d0SPaul Walmsley struct sifive_serial_port *ssp;
81445c054d0SPaul Walmsley int baud = SIFIVE_DEFAULT_BAUD_RATE;
81545c054d0SPaul Walmsley int bits = 8;
81645c054d0SPaul Walmsley int parity = 'n';
81745c054d0SPaul Walmsley int flow = 'n';
81845c054d0SPaul Walmsley
81945c054d0SPaul Walmsley if (co->index < 0 || co->index >= SIFIVE_SERIAL_MAX_PORTS)
82045c054d0SPaul Walmsley return -ENODEV;
82145c054d0SPaul Walmsley
82245c054d0SPaul Walmsley ssp = sifive_serial_console_ports[co->index];
82345c054d0SPaul Walmsley if (!ssp)
82445c054d0SPaul Walmsley return -ENODEV;
82545c054d0SPaul Walmsley
82645c054d0SPaul Walmsley if (options)
82745c054d0SPaul Walmsley uart_parse_options(options, &baud, &parity, &bits, &flow);
82845c054d0SPaul Walmsley
82945c054d0SPaul Walmsley return uart_set_options(&ssp->port, co, baud, parity, bits, flow);
83045c054d0SPaul Walmsley }
83145c054d0SPaul Walmsley
83245c054d0SPaul Walmsley static struct uart_driver sifive_serial_uart_driver;
83345c054d0SPaul Walmsley
83445c054d0SPaul Walmsley static struct console sifive_serial_console = {
83545c054d0SPaul Walmsley .name = SIFIVE_TTY_PREFIX,
83645c054d0SPaul Walmsley .write = sifive_serial_console_write,
83745c054d0SPaul Walmsley .device = uart_console_device,
83845c054d0SPaul Walmsley .setup = sifive_serial_console_setup,
83945c054d0SPaul Walmsley .flags = CON_PRINTBUFFER,
84045c054d0SPaul Walmsley .index = -1,
84145c054d0SPaul Walmsley .data = &sifive_serial_uart_driver,
84245c054d0SPaul Walmsley };
84345c054d0SPaul Walmsley
sifive_console_init(void)84445c054d0SPaul Walmsley static int __init sifive_console_init(void)
84545c054d0SPaul Walmsley {
84645c054d0SPaul Walmsley register_console(&sifive_serial_console);
84745c054d0SPaul Walmsley return 0;
84845c054d0SPaul Walmsley }
84945c054d0SPaul Walmsley
85045c054d0SPaul Walmsley console_initcall(sifive_console_init);
85145c054d0SPaul Walmsley
__ssp_add_console_port(struct sifive_serial_port * ssp)85245c054d0SPaul Walmsley static void __ssp_add_console_port(struct sifive_serial_port *ssp)
85345c054d0SPaul Walmsley {
85445c054d0SPaul Walmsley sifive_serial_console_ports[ssp->port.line] = ssp;
85545c054d0SPaul Walmsley }
85645c054d0SPaul Walmsley
__ssp_remove_console_port(struct sifive_serial_port * ssp)85745c054d0SPaul Walmsley static void __ssp_remove_console_port(struct sifive_serial_port *ssp)
85845c054d0SPaul Walmsley {
85927e8c8b4SColin Ian King sifive_serial_console_ports[ssp->port.line] = NULL;
86045c054d0SPaul Walmsley }
86145c054d0SPaul Walmsley
86245c054d0SPaul Walmsley #define SIFIVE_SERIAL_CONSOLE (&sifive_serial_console)
86345c054d0SPaul Walmsley
86445c054d0SPaul Walmsley #else
86545c054d0SPaul Walmsley
86645c054d0SPaul Walmsley #define SIFIVE_SERIAL_CONSOLE NULL
86745c054d0SPaul Walmsley
__ssp_add_console_port(struct sifive_serial_port * ssp)86845c054d0SPaul Walmsley static void __ssp_add_console_port(struct sifive_serial_port *ssp)
86945c054d0SPaul Walmsley {}
__ssp_remove_console_port(struct sifive_serial_port * ssp)87045c054d0SPaul Walmsley static void __ssp_remove_console_port(struct sifive_serial_port *ssp)
87145c054d0SPaul Walmsley {}
87245c054d0SPaul Walmsley
87345c054d0SPaul Walmsley #endif
87445c054d0SPaul Walmsley
87545c054d0SPaul Walmsley static const struct uart_ops sifive_serial_uops = {
87645c054d0SPaul Walmsley .tx_empty = sifive_serial_tx_empty,
87745c054d0SPaul Walmsley .set_mctrl = sifive_serial_set_mctrl,
87845c054d0SPaul Walmsley .get_mctrl = sifive_serial_get_mctrl,
87945c054d0SPaul Walmsley .stop_tx = sifive_serial_stop_tx,
88045c054d0SPaul Walmsley .start_tx = sifive_serial_start_tx,
88145c054d0SPaul Walmsley .stop_rx = sifive_serial_stop_rx,
88245c054d0SPaul Walmsley .break_ctl = sifive_serial_break_ctl,
88345c054d0SPaul Walmsley .startup = sifive_serial_startup,
88445c054d0SPaul Walmsley .shutdown = sifive_serial_shutdown,
88545c054d0SPaul Walmsley .set_termios = sifive_serial_set_termios,
88645c054d0SPaul Walmsley .type = sifive_serial_type,
88745c054d0SPaul Walmsley .release_port = sifive_serial_release_port,
88845c054d0SPaul Walmsley .request_port = sifive_serial_request_port,
88945c054d0SPaul Walmsley .config_port = sifive_serial_config_port,
89045c054d0SPaul Walmsley .verify_port = sifive_serial_verify_port,
891630db5cbSVincent Chen #ifdef CONFIG_CONSOLE_POLL
892630db5cbSVincent Chen .poll_get_char = sifive_serial_poll_get_char,
893630db5cbSVincent Chen .poll_put_char = sifive_serial_poll_put_char,
894630db5cbSVincent Chen #endif
89545c054d0SPaul Walmsley };
89645c054d0SPaul Walmsley
89745c054d0SPaul Walmsley static struct uart_driver sifive_serial_uart_driver = {
89845c054d0SPaul Walmsley .owner = THIS_MODULE,
89945c054d0SPaul Walmsley .driver_name = SIFIVE_SERIAL_NAME,
90045c054d0SPaul Walmsley .dev_name = SIFIVE_TTY_PREFIX,
90145c054d0SPaul Walmsley .nr = SIFIVE_SERIAL_MAX_PORTS,
90245c054d0SPaul Walmsley .cons = SIFIVE_SERIAL_CONSOLE,
90345c054d0SPaul Walmsley };
90445c054d0SPaul Walmsley
sifive_serial_probe(struct platform_device * pdev)90545c054d0SPaul Walmsley static int sifive_serial_probe(struct platform_device *pdev)
90645c054d0SPaul Walmsley {
90745c054d0SPaul Walmsley struct sifive_serial_port *ssp;
90845c054d0SPaul Walmsley struct resource *mem;
90945c054d0SPaul Walmsley struct clk *clk;
91045c054d0SPaul Walmsley void __iomem *base;
91145c054d0SPaul Walmsley int irq, id, r;
91245c054d0SPaul Walmsley
91345c054d0SPaul Walmsley irq = platform_get_irq(pdev, 0);
9141df21786SStephen Boyd if (irq < 0)
91545c054d0SPaul Walmsley return -EPROBE_DEFER;
91645c054d0SPaul Walmsley
917b75c1da9SYangtao Li base = devm_platform_get_and_ioremap_resource(pdev, 0, &mem);
918b75c1da9SYangtao Li if (IS_ERR(base))
91945c054d0SPaul Walmsley return PTR_ERR(base);
92045c054d0SPaul Walmsley
92164379204SOlof Johansson clk = devm_clk_get_enabled(&pdev->dev, NULL);
92245c054d0SPaul Walmsley if (IS_ERR(clk)) {
92345c054d0SPaul Walmsley dev_err(&pdev->dev, "unable to find controller clock\n");
92445c054d0SPaul Walmsley return PTR_ERR(clk);
92545c054d0SPaul Walmsley }
92645c054d0SPaul Walmsley
92745c054d0SPaul Walmsley id = of_alias_get_id(pdev->dev.of_node, "serial");
92845c054d0SPaul Walmsley if (id < 0) {
92945c054d0SPaul Walmsley dev_err(&pdev->dev, "missing aliases entry\n");
93045c054d0SPaul Walmsley return id;
93145c054d0SPaul Walmsley }
93245c054d0SPaul Walmsley
93345c054d0SPaul Walmsley #ifdef CONFIG_SERIAL_SIFIVE_CONSOLE
93445c054d0SPaul Walmsley if (id > SIFIVE_SERIAL_MAX_PORTS) {
93545c054d0SPaul Walmsley dev_err(&pdev->dev, "too many UARTs (%d)\n", id);
93645c054d0SPaul Walmsley return -EINVAL;
93745c054d0SPaul Walmsley }
93845c054d0SPaul Walmsley #endif
93945c054d0SPaul Walmsley
94045c054d0SPaul Walmsley ssp = devm_kzalloc(&pdev->dev, sizeof(*ssp), GFP_KERNEL);
94145c054d0SPaul Walmsley if (!ssp)
94245c054d0SPaul Walmsley return -ENOMEM;
94345c054d0SPaul Walmsley
94445c054d0SPaul Walmsley ssp->port.dev = &pdev->dev;
94545c054d0SPaul Walmsley ssp->port.type = PORT_SIFIVE_V0;
94645c054d0SPaul Walmsley ssp->port.iotype = UPIO_MEM;
94745c054d0SPaul Walmsley ssp->port.irq = irq;
94845c054d0SPaul Walmsley ssp->port.fifosize = SIFIVE_TX_FIFO_DEPTH;
94945c054d0SPaul Walmsley ssp->port.ops = &sifive_serial_uops;
95045c054d0SPaul Walmsley ssp->port.line = id;
95145c054d0SPaul Walmsley ssp->port.mapbase = mem->start;
95245c054d0SPaul Walmsley ssp->port.membase = base;
95345c054d0SPaul Walmsley ssp->dev = &pdev->dev;
95445c054d0SPaul Walmsley ssp->clk = clk;
95545c054d0SPaul Walmsley ssp->clk_notifier.notifier_call = sifive_serial_clk_notifier;
95645c054d0SPaul Walmsley
95745c054d0SPaul Walmsley r = clk_notifier_register(ssp->clk, &ssp->clk_notifier);
95845c054d0SPaul Walmsley if (r) {
95945c054d0SPaul Walmsley dev_err(&pdev->dev, "could not register clock notifier: %d\n",
96045c054d0SPaul Walmsley r);
96145c054d0SPaul Walmsley goto probe_out1;
96245c054d0SPaul Walmsley }
96345c054d0SPaul Walmsley
96445c054d0SPaul Walmsley /* Set up clock divider */
9654487cd3eSMaciej W. Rozycki ssp->port.uartclk = clk_get_rate(ssp->clk);
96645c054d0SPaul Walmsley ssp->baud_rate = SIFIVE_DEFAULT_BAUD_RATE;
96745c054d0SPaul Walmsley __ssp_update_div(ssp);
96845c054d0SPaul Walmsley
96945c054d0SPaul Walmsley platform_set_drvdata(pdev, ssp);
97045c054d0SPaul Walmsley
97145c054d0SPaul Walmsley /* Enable transmits and set the watermark level to 1 */
97245c054d0SPaul Walmsley __ssp_writel((1 << SIFIVE_SERIAL_TXCTRL_TXCNT_SHIFT) |
97345c054d0SPaul Walmsley SIFIVE_SERIAL_TXCTRL_TXEN_MASK,
97445c054d0SPaul Walmsley SIFIVE_SERIAL_TXCTRL_OFFS, ssp);
97545c054d0SPaul Walmsley
97645c054d0SPaul Walmsley /* Enable receives and set the watermark level to 0 */
97745c054d0SPaul Walmsley __ssp_writel((0 << SIFIVE_SERIAL_RXCTRL_RXCNT_SHIFT) |
97845c054d0SPaul Walmsley SIFIVE_SERIAL_RXCTRL_RXEN_MASK,
97945c054d0SPaul Walmsley SIFIVE_SERIAL_RXCTRL_OFFS, ssp);
98045c054d0SPaul Walmsley
98145c054d0SPaul Walmsley r = request_irq(ssp->port.irq, sifive_serial_irq, ssp->port.irqflags,
98245c054d0SPaul Walmsley dev_name(&pdev->dev), ssp);
98345c054d0SPaul Walmsley if (r) {
98445c054d0SPaul Walmsley dev_err(&pdev->dev, "could not attach interrupt: %d\n", r);
98545c054d0SPaul Walmsley goto probe_out2;
98645c054d0SPaul Walmsley }
98745c054d0SPaul Walmsley
98845c054d0SPaul Walmsley __ssp_add_console_port(ssp);
98945c054d0SPaul Walmsley
99045c054d0SPaul Walmsley r = uart_add_one_port(&sifive_serial_uart_driver, &ssp->port);
99145c054d0SPaul Walmsley if (r != 0) {
99245c054d0SPaul Walmsley dev_err(&pdev->dev, "could not add uart: %d\n", r);
99345c054d0SPaul Walmsley goto probe_out3;
99445c054d0SPaul Walmsley }
99545c054d0SPaul Walmsley
99645c054d0SPaul Walmsley return 0;
99745c054d0SPaul Walmsley
99845c054d0SPaul Walmsley probe_out3:
99945c054d0SPaul Walmsley __ssp_remove_console_port(ssp);
100045c054d0SPaul Walmsley free_irq(ssp->port.irq, ssp);
100145c054d0SPaul Walmsley probe_out2:
100245c054d0SPaul Walmsley clk_notifier_unregister(ssp->clk, &ssp->clk_notifier);
100345c054d0SPaul Walmsley probe_out1:
100445c054d0SPaul Walmsley return r;
100545c054d0SPaul Walmsley }
100645c054d0SPaul Walmsley
sifive_serial_remove(struct platform_device * dev)10070a208f3dSUwe Kleine-König static void sifive_serial_remove(struct platform_device *dev)
100845c054d0SPaul Walmsley {
100945c054d0SPaul Walmsley struct sifive_serial_port *ssp = platform_get_drvdata(dev);
101045c054d0SPaul Walmsley
101145c054d0SPaul Walmsley __ssp_remove_console_port(ssp);
101245c054d0SPaul Walmsley uart_remove_one_port(&sifive_serial_uart_driver, &ssp->port);
101345c054d0SPaul Walmsley free_irq(ssp->port.irq, ssp);
101445c054d0SPaul Walmsley clk_notifier_unregister(ssp->clk, &ssp->clk_notifier);
101545c054d0SPaul Walmsley }
101645c054d0SPaul Walmsley
sifive_serial_suspend(struct device * dev)10178a6498f2SNick Hu static int sifive_serial_suspend(struct device *dev)
10188a6498f2SNick Hu {
10198a6498f2SNick Hu struct sifive_serial_port *ssp = dev_get_drvdata(dev);
10208a6498f2SNick Hu
10218a6498f2SNick Hu return uart_suspend_port(&sifive_serial_uart_driver, &ssp->port);
10228a6498f2SNick Hu }
10238a6498f2SNick Hu
sifive_serial_resume(struct device * dev)10248a6498f2SNick Hu static int sifive_serial_resume(struct device *dev)
10258a6498f2SNick Hu {
10268a6498f2SNick Hu struct sifive_serial_port *ssp = dev_get_drvdata(dev);
10278a6498f2SNick Hu
10288a6498f2SNick Hu return uart_resume_port(&sifive_serial_uart_driver, &ssp->port);
10298a6498f2SNick Hu }
10308a6498f2SNick Hu
103117fabec9SSamuel Holland static DEFINE_SIMPLE_DEV_PM_OPS(sifive_uart_pm_ops, sifive_serial_suspend,
10328a6498f2SNick Hu sifive_serial_resume);
10338a6498f2SNick Hu
103445c054d0SPaul Walmsley static const struct of_device_id sifive_serial_of_match[] = {
103542100227SSebastian Andrzej Siewior { .compatible = "sifive,fu540-c000-uart" },
103645c054d0SPaul Walmsley { .compatible = "sifive,uart0" },
103745c054d0SPaul Walmsley {},
103845c054d0SPaul Walmsley };
103945c054d0SPaul Walmsley MODULE_DEVICE_TABLE(of, sifive_serial_of_match);
104045c054d0SPaul Walmsley
104145c054d0SPaul Walmsley static struct platform_driver sifive_serial_platform_driver = {
104245c054d0SPaul Walmsley .probe = sifive_serial_probe,
1043*5cbb9b17SUwe Kleine-König .remove = sifive_serial_remove,
104445c054d0SPaul Walmsley .driver = {
104545c054d0SPaul Walmsley .name = SIFIVE_SERIAL_NAME,
10468a6498f2SNick Hu .pm = pm_sleep_ptr(&sifive_uart_pm_ops),
10470aaf7818SRuan Jinjie .of_match_table = sifive_serial_of_match,
104845c054d0SPaul Walmsley },
104945c054d0SPaul Walmsley };
105045c054d0SPaul Walmsley
sifive_serial_init(void)105145c054d0SPaul Walmsley static int __init sifive_serial_init(void)
105245c054d0SPaul Walmsley {
105345c054d0SPaul Walmsley int r;
105445c054d0SPaul Walmsley
105545c054d0SPaul Walmsley r = uart_register_driver(&sifive_serial_uart_driver);
105645c054d0SPaul Walmsley if (r)
105745c054d0SPaul Walmsley goto init_out1;
105845c054d0SPaul Walmsley
105945c054d0SPaul Walmsley r = platform_driver_register(&sifive_serial_platform_driver);
106045c054d0SPaul Walmsley if (r)
106145c054d0SPaul Walmsley goto init_out2;
106245c054d0SPaul Walmsley
106345c054d0SPaul Walmsley return 0;
106445c054d0SPaul Walmsley
106545c054d0SPaul Walmsley init_out2:
106645c054d0SPaul Walmsley uart_unregister_driver(&sifive_serial_uart_driver);
106745c054d0SPaul Walmsley init_out1:
106845c054d0SPaul Walmsley return r;
106945c054d0SPaul Walmsley }
107045c054d0SPaul Walmsley
sifive_serial_exit(void)107145c054d0SPaul Walmsley static void __exit sifive_serial_exit(void)
107245c054d0SPaul Walmsley {
107345c054d0SPaul Walmsley platform_driver_unregister(&sifive_serial_platform_driver);
107445c054d0SPaul Walmsley uart_unregister_driver(&sifive_serial_uart_driver);
107545c054d0SPaul Walmsley }
107645c054d0SPaul Walmsley
107745c054d0SPaul Walmsley module_init(sifive_serial_init);
107845c054d0SPaul Walmsley module_exit(sifive_serial_exit);
107945c054d0SPaul Walmsley
108045c054d0SPaul Walmsley MODULE_DESCRIPTION("SiFive UART serial driver");
108145c054d0SPaul Walmsley MODULE_LICENSE("GPL");
108245c054d0SPaul Walmsley MODULE_AUTHOR("Paul Walmsley <paul@pwsan.com>");
1083