218  * @ssp: pointer to a struct sifive_serial_port record
221  * IP block base, given a pointer @ssp to a struct sifive_serial_port record.
225 static void __ssp_writel(u32 v, u16 offs, struct sifive_serial_port *ssp)  in __ssp_writel()  argument
227 	__ssp_early_writel(v, offs, &ssp->port);  in __ssp_writel()
232  * @ssp: pointer to a struct sifive_serial_port record
236  * IP block base, given a pointer @ssp to a struct sifive_serial_port record.
242 static u32 __ssp_readl(struct sifive_serial_port *ssp, u16 offs)  in __ssp_readl()  argument
244 	return __ssp_early_readl(&ssp->port, offs);  in __ssp_readl()
249  * @ssp: pointer to a struct sifive_serial_port
258 static int sifive_serial_is_txfifo_full(struct sifive_serial_port *ssp)  in sifive_serial_is_txfifo_full()  argument
260 	return __ssp_readl(ssp, SIFIVE_SERIAL_TXDATA_OFFS) &  in sifive_serial_is_txfifo_full()
266  * @ssp: pointer to a struct sifive_serial_port
269  * Enqueue a byte @ch onto the transmit FIFO, given a pointer @ssp to the
275 static void __ssp_transmit_char(struct sifive_serial_port *ssp, int ch)  in __ssp_transmit_char()  argument
277 	__ssp_writel(ch, SIFIVE_SERIAL_TXDATA_OFFS, ssp);  in __ssp_transmit_char()
282  * @ssp: pointer to a struct sifive_serial_port
287  * Context: Any context.  Expects @ssp->port.lock to be held by caller.
289 static void __ssp_transmit_chars(struct sifive_serial_port *ssp)  in __ssp_transmit_chars()  argument
291 	struct circ_buf *xmit = &ssp->port.state->xmit;  in __ssp_transmit_chars()
294 	if (ssp->port.x_char) {  in __ssp_transmit_chars()
295 		__ssp_transmit_char(ssp, ssp->port.x_char);  in __ssp_transmit_chars()
296 		ssp->port.icount.tx++;  in __ssp_transmit_chars()
297 		ssp->port.x_char = 0;  in __ssp_transmit_chars()
300 	if (uart_circ_empty(xmit) || uart_tx_stopped(&ssp->port)) {  in __ssp_transmit_chars()
301 		sifive_serial_stop_tx(&ssp->port);  in __ssp_transmit_chars()
306 		__ssp_transmit_char(ssp, xmit->buf[xmit->tail]);  in __ssp_transmit_chars()
308 		ssp->port.icount.tx++;  in __ssp_transmit_chars()
314 		uart_write_wakeup(&ssp->port);  in __ssp_transmit_chars()
317 		sifive_serial_stop_tx(&ssp->port);  in __ssp_transmit_chars()
322  * @ssp: pointer to a struct sifive_serial_port
325  * on the SiFive UART referred to by @ssp.
327 static void __ssp_enable_txwm(struct sifive_serial_port *ssp)  in __ssp_enable_txwm()  argument
329 	if (ssp->ier & SIFIVE_SERIAL_IE_TXWM_MASK)  in __ssp_enable_txwm()
332 	ssp->ier |= SIFIVE_SERIAL_IE_TXWM_MASK;  in __ssp_enable_txwm()
333 	__ssp_writel(ssp->ier, SIFIVE_SERIAL_IE_OFFS, ssp);  in __ssp_enable_txwm()
338  * @ssp: pointer to a struct sifive_serial_port
341  * on the SiFive UART referred to by @ssp.
343 static void __ssp_enable_rxwm(struct sifive_serial_port *ssp)  in __ssp_enable_rxwm()  argument
345 	if (ssp->ier & SIFIVE_SERIAL_IE_RXWM_MASK)  in __ssp_enable_rxwm()
348 	ssp->ier |= SIFIVE_SERIAL_IE_RXWM_MASK;  in __ssp_enable_rxwm()
349 	__ssp_writel(ssp->ier, SIFIVE_SERIAL_IE_OFFS, ssp);  in __ssp_enable_rxwm()
354  * @ssp: pointer to a struct sifive_serial_port
357  * on the UART referred to by @ssp.
359 static void __ssp_disable_txwm(struct sifive_serial_port *ssp)  in __ssp_disable_txwm()  argument
361 	if (!(ssp->ier & SIFIVE_SERIAL_IE_TXWM_MASK))  in __ssp_disable_txwm()
364 	ssp->ier &= ~SIFIVE_SERIAL_IE_TXWM_MASK;  in __ssp_disable_txwm()
365 	__ssp_writel(ssp->ier, SIFIVE_SERIAL_IE_OFFS, ssp);  in __ssp_disable_txwm()
370  * @ssp: pointer to a struct sifive_serial_port
373  * on the UART referred to by @ssp.
375 static void __ssp_disable_rxwm(struct sifive_serial_port *ssp)  in __ssp_disable_rxwm()  argument
377 	if (!(ssp->ier & SIFIVE_SERIAL_IE_RXWM_MASK))  in __ssp_disable_rxwm()
380 	ssp->ier &= ~SIFIVE_SERIAL_IE_RXWM_MASK;  in __ssp_disable_rxwm()
381 	__ssp_writel(ssp->ier, SIFIVE_SERIAL_IE_OFFS, ssp);  in __ssp_disable_rxwm()
386  * @ssp: pointer to a struct sifive_serial_port
390  * @ssp, and to return it.  Also returns the RX FIFO empty bit in
396 static char __ssp_receive_char(struct sifive_serial_port *ssp, char *is_empty)  in __ssp_receive_char()  argument
401 	v = __ssp_readl(ssp, SIFIVE_SERIAL_RXDATA_OFFS);  in __ssp_receive_char()
417  * @ssp: pointer to a struct sifive_serial_port
420  * to by @ssp and pass them up to the Linux serial layer.
422  * Context: Expects ssp->port.lock to be held by caller.
424 static void __ssp_receive_chars(struct sifive_serial_port *ssp)  in __ssp_receive_chars()  argument
431 		ch = __ssp_receive_char(ssp, &is_empty);  in __ssp_receive_chars()
435 		ssp->port.icount.rx++;  in __ssp_receive_chars()
436 		uart_insert_char(&ssp->port, 0, 0, ch, TTY_NORMAL);  in __ssp_receive_chars()
439 	tty_flip_buffer_push(&ssp->port.state->port);  in __ssp_receive_chars()
444  * @ssp: pointer to a struct sifive_serial_port
447  * and target line rate referred to by @ssp and write it into the
450 static void __ssp_update_div(struct sifive_serial_port *ssp)  in __ssp_update_div()  argument
454 	div = DIV_ROUND_UP(ssp->port.uartclk, ssp->baud_rate) - 1;  in __ssp_update_div()
456 	__ssp_writel(div, SIFIVE_SERIAL_DIV_OFFS, ssp);  in __ssp_update_div()
461  * @ssp: pointer to a struct sifive_serial_port
465  * SiFive UART described by @ssp and program it into the UART.  There may
469 static void __ssp_update_baud_rate(struct sifive_serial_port *ssp,  in __ssp_update_baud_rate()  argument
472 	if (ssp->baud_rate == rate)  in __ssp_update_baud_rate()
475 	ssp->baud_rate = rate;  in __ssp_update_baud_rate()
476 	__ssp_update_div(ssp);  in __ssp_update_baud_rate()
481  * @ssp: pointer to a struct sifive_serial_port
484  * Program the SiFive UART referred to by @ssp to use @nstop stop bits.
486 static void __ssp_set_stop_bits(struct sifive_serial_port *ssp, char nstop)  in __ssp_set_stop_bits()  argument
495 	v = __ssp_readl(ssp, SIFIVE_SERIAL_TXCTRL_OFFS);  in __ssp_set_stop_bits()
498 	__ssp_writel(v, SIFIVE_SERIAL_TXCTRL_OFFS, ssp);  in __ssp_set_stop_bits()
503  * @ssp: pointer to a struct sifive_serial_port
505  * Delay while the UART TX FIFO referred to by @ssp is marked as full.
509 static void __maybe_unused __ssp_wait_for_xmitr(struct sifive_serial_port *ssp)  in __ssp_wait_for_xmitr()  argument
511 	while (sifive_serial_is_txfifo_full(ssp))  in __ssp_wait_for_xmitr()
521 	struct sifive_serial_port *ssp = port_to_sifive_serial_port(port);  in sifive_serial_stop_tx()  local
523 	__ssp_disable_txwm(ssp);  in sifive_serial_stop_tx()
528 	struct sifive_serial_port *ssp = port_to_sifive_serial_port(port);  in sifive_serial_stop_rx()  local
530 	__ssp_disable_rxwm(ssp);  in sifive_serial_stop_rx()
535 	struct sifive_serial_port *ssp = port_to_sifive_serial_port(port);  in sifive_serial_start_tx()  local
537 	__ssp_enable_txwm(ssp);  in sifive_serial_start_tx()
542 	struct sifive_serial_port *ssp = dev_id;  in sifive_serial_irq()  local
545 	spin_lock(&ssp->port.lock);  in sifive_serial_irq()
547 	ip = __ssp_readl(ssp, SIFIVE_SERIAL_IP_OFFS);  in sifive_serial_irq()
549 		spin_unlock(&ssp->port.lock);  in sifive_serial_irq()
554 		__ssp_receive_chars(ssp);  in sifive_serial_irq()
556 		__ssp_transmit_chars(ssp);  in sifive_serial_irq()
558 	spin_unlock(&ssp->port.lock);  in sifive_serial_irq()
585 	struct sifive_serial_port *ssp = port_to_sifive_serial_port(port);  in sifive_serial_startup()  local
587 	__ssp_enable_rxwm(ssp);  in sifive_serial_startup()
594 	struct sifive_serial_port *ssp = port_to_sifive_serial_port(port);  in sifive_serial_shutdown()  local
596 	__ssp_disable_rxwm(ssp);  in sifive_serial_shutdown()
597 	__ssp_disable_txwm(ssp);  in sifive_serial_shutdown()
617 	struct sifive_serial_port *ssp = notifier_to_sifive_serial_port(nb);  in sifive_serial_clk_notifier()  local
626 		__ssp_wait_for_xmitr(ssp);  in sifive_serial_clk_notifier()
636 		udelay(DIV_ROUND_UP(12 * 1000 * 1000, ssp->baud_rate));  in sifive_serial_clk_notifier()
639 	if (event == POST_RATE_CHANGE && ssp->port.uartclk != cnd->new_rate) {  in sifive_serial_clk_notifier()
640 		ssp->port.uartclk = cnd->new_rate;  in sifive_serial_clk_notifier()
641 		__ssp_update_div(ssp);  in sifive_serial_clk_notifier()
651 	struct sifive_serial_port *ssp = port_to_sifive_serial_port(port);  in sifive_serial_set_termios()  local
658 		dev_err_once(ssp->port.dev, "only 8-bit words supported\n");  in sifive_serial_set_termios()
663 		dev_err_once(ssp->port.dev, "parity checking not supported\n");  in sifive_serial_set_termios()
665 		dev_err_once(ssp->port.dev, "BREAK detection not supported\n");  in sifive_serial_set_termios()
670 	__ssp_set_stop_bits(ssp, nstop);  in sifive_serial_set_termios()
674 				  ssp->port.uartclk / 16);  in sifive_serial_set_termios()
675 	__ssp_update_baud_rate(ssp, rate);  in sifive_serial_set_termios()
677 	spin_lock_irqsave(&ssp->port.lock, flags);  in sifive_serial_set_termios()
682 	ssp->port.read_status_mask = 0;  in sifive_serial_set_termios()
685 	v = __ssp_readl(ssp, SIFIVE_SERIAL_RXCTRL_OFFS);  in sifive_serial_set_termios()
692 		__ssp_writel(v, SIFIVE_SERIAL_RXCTRL_OFFS, ssp);  in sifive_serial_set_termios()
694 	spin_unlock_irqrestore(&ssp->port.lock, flags);  in sifive_serial_set_termios()
708 	struct sifive_serial_port *ssp = port_to_sifive_serial_port(port);  in sifive_serial_config_port()  local
710 	ssp->port.type = PORT_SIFIVE_V0;  in sifive_serial_config_port()
727 	struct sifive_serial_port *ssp = port_to_sifive_serial_port(port);  in sifive_serial_poll_get_char()  local
730 	ch = __ssp_receive_char(ssp, &is_empty);  in sifive_serial_poll_get_char()
740 	struct sifive_serial_port *ssp = port_to_sifive_serial_port(port);  in sifive_serial_poll_put_char()  local
742 	__ssp_wait_for_xmitr(ssp);  in sifive_serial_poll_put_char()
743 	__ssp_transmit_char(ssp, c);  in sifive_serial_poll_put_char()
798 	struct sifive_serial_port *ssp = port_to_sifive_serial_port(port);  in sifive_serial_console_putchar()  local
800 	__ssp_wait_for_xmitr(ssp);  in sifive_serial_console_putchar()
801 	__ssp_transmit_char(ssp, ch);  in sifive_serial_console_putchar()
807 	struct sifive_serial_port *ssp = sifive_serial_console_ports[co->index];  in sifive_serial_console_write()  local
812 	if (!ssp)  in sifive_serial_console_write()
816 	if (ssp->port.sysrq)  in sifive_serial_console_write()
819 		locked = spin_trylock(&ssp->port.lock);  in sifive_serial_console_write()
821 		spin_lock(&ssp->port.lock);  in sifive_serial_console_write()
823 	ier = __ssp_readl(ssp, SIFIVE_SERIAL_IE_OFFS);  in sifive_serial_console_write()
824 	__ssp_writel(0, SIFIVE_SERIAL_IE_OFFS, ssp);  in sifive_serial_console_write()
826 	uart_console_write(&ssp->port, s, count, sifive_serial_console_putchar);  in sifive_serial_console_write()
828 	__ssp_writel(ier, SIFIVE_SERIAL_IE_OFFS, ssp);  in sifive_serial_console_write()
831 		spin_unlock(&ssp->port.lock);  in sifive_serial_console_write()
837 	struct sifive_serial_port *ssp;  in sifive_serial_console_setup()  local
846 	ssp = sifive_serial_console_ports[co->index];  in sifive_serial_console_setup()
847 	if (!ssp)  in sifive_serial_console_setup()
853 	return uart_set_options(&ssp->port, co, baud, parity, bits, flow);  in sifive_serial_console_setup()
876 static void __ssp_add_console_port(struct sifive_serial_port *ssp)  in __ssp_add_console_port()  argument
878 	sifive_serial_console_ports[ssp->port.line] = ssp;  in __ssp_add_console_port()
881 static void __ssp_remove_console_port(struct sifive_serial_port *ssp)  in __ssp_remove_console_port()  argument
883 	sifive_serial_console_ports[ssp->port.line] = NULL;  in __ssp_remove_console_port()
892 static void __ssp_add_console_port(struct sifive_serial_port *ssp)  in __ssp_add_console_port()  argument
894 static void __ssp_remove_console_port(struct sifive_serial_port *ssp)  in __ssp_remove_console_port()  argument
931 	struct sifive_serial_port *ssp;  in sifive_serial_probe()  local
967 	ssp = devm_kzalloc(&pdev->dev, sizeof(*ssp), GFP_KERNEL);  in sifive_serial_probe()
968 	if (!ssp)  in sifive_serial_probe()
971 	ssp->port.dev = &pdev->dev;  in sifive_serial_probe()
972 	ssp->port.type = PORT_SIFIVE_V0;  in sifive_serial_probe()
973 	ssp->port.iotype = UPIO_MEM;  in sifive_serial_probe()
974 	ssp->port.irq = irq;  in sifive_serial_probe()
975 	ssp->port.fifosize = SIFIVE_TX_FIFO_DEPTH;  in sifive_serial_probe()
976 	ssp->port.ops = &sifive_serial_uops;  in sifive_serial_probe()
977 	ssp->port.line = id;  in sifive_serial_probe()
978 	ssp->port.mapbase = mem->start;  in sifive_serial_probe()
979 	ssp->port.membase = base;  in sifive_serial_probe()
980 	ssp->dev = &pdev->dev;  in sifive_serial_probe()
981 	ssp->clk = clk;  in sifive_serial_probe()
982 	ssp->clk_notifier.notifier_call = sifive_serial_clk_notifier;  in sifive_serial_probe()
984 	r = clk_notifier_register(ssp->clk, &ssp->clk_notifier);  in sifive_serial_probe()
992 	ssp->port.uartclk = clk_get_rate(ssp->clk);  in sifive_serial_probe()
993 	ssp->baud_rate = SIFIVE_DEFAULT_BAUD_RATE;  in sifive_serial_probe()
994 	__ssp_update_div(ssp);  in sifive_serial_probe()
996 	platform_set_drvdata(pdev, ssp);  in sifive_serial_probe()
1001 		     SIFIVE_SERIAL_TXCTRL_OFFS, ssp);  in sifive_serial_probe()
1006 		     SIFIVE_SERIAL_RXCTRL_OFFS, ssp);  in sifive_serial_probe()
1008 	r = request_irq(ssp->port.irq, sifive_serial_irq, ssp->port.irqflags,  in sifive_serial_probe()
1009 			dev_name(&pdev->dev), ssp);  in sifive_serial_probe()
1015 	__ssp_add_console_port(ssp);  in sifive_serial_probe()
1017 	r = uart_add_one_port(&sifive_serial_uart_driver, &ssp->port);  in sifive_serial_probe()
1026 	__ssp_remove_console_port(ssp);  in sifive_serial_probe()
1027 	free_irq(ssp->port.irq, ssp);  in sifive_serial_probe()
1029 	clk_notifier_unregister(ssp->clk, &ssp->clk_notifier);  in sifive_serial_probe()
1036 	struct sifive_serial_port *ssp = platform_get_drvdata(dev);  in sifive_serial_remove()  local
1038 	__ssp_remove_console_port(ssp);  in sifive_serial_remove()
1039 	uart_remove_one_port(&sifive_serial_uart_driver, &ssp->port);  in sifive_serial_remove()
1040 	free_irq(ssp->port.irq, ssp);  in sifive_serial_remove()
1041 	clk_notifier_unregister(ssp->clk, &ssp->clk_notifier);  in sifive_serial_remove()