From 42eeed6d9f31e6063bf98d71212a6de3aac8cdd3 Mon Sep 17 00:00:00 2001 From: Biju Das Date: Sat, 29 Nov 2025 16:43:13 +0000 Subject: [PATCH] serial: sh-sci: Add support for RZ/G3E RSCI Add support for RZ/G3E RSCI. RSCI IP found on the RZ/G3E SoC is similar to RZ/T2H, but it has a 32-stage FIFO. It has 6 clocks(5 module clocks + 1 external clock) instead of 3 clocks(2 module clocks + 1 external clock) on T2H, has 6 irqs compared to 4 on RZ/T2H and has multiple resets. Add support for the hardware flow control. Signed-off-by: Biju Das Tested-by: Lad Prabhakar Link: https://patch.msgid.link/20251129164325.209213-18-biju.das.jz@bp.renesas.com Signed-off-by: Greg Kroah-Hartman --- drivers/tty/serial/rsci.c | 260 ++++++++++++++++++++++++++++++++++-- drivers/tty/serial/rsci.h | 1 + drivers/tty/serial/sh-sci.c | 5 + 3 files changed, 257 insertions(+), 9 deletions(-) diff --git a/drivers/tty/serial/rsci.c b/drivers/tty/serial/rsci.c index 70ff81fdc027..1ef7c6d61707 100644 --- a/drivers/tty/serial/rsci.c +++ b/drivers/tty/serial/rsci.c @@ -11,6 +11,8 @@ #include #include #include + +#include "serial_mctrl_gpio.h" #include "rsci.h" MODULE_IMPORT_NS("SH_SCI"); @@ -59,6 +61,41 @@ MODULE_IMPORT_NS("SH_SCI"); #define CCR1_CTSPEN BIT(1) /* CTS External Pin Enable */ #define CCR1_CTSE BIT(0) /* CTS Enable */ +/* CCR2 (Common Control Register 2) */ +#define CCR2_INIT 0xFF000004 +#define CCR2_CKS_TCLK (0) /* TCLK clock */ +#define CCR2_CKS_TCLK_DIV4 BIT(20) /* TCLK/4 clock */ +#define CCR2_CKS_TCLK_DIV16 BIT(21) /* TCLK16 clock */ +#define CCR2_CKS_TCLK_DIV64 (BIT(21) | BIT(20)) /* TCLK/64 clock */ +#define CCR2_BRME BIT(16) /* Bitrate Modulation Enable */ +#define CCR2_ABCSE BIT(6) /* Asynchronous Mode Extended Base Clock Select */ +#define CCR2_ABCS BIT(5) /* Asynchronous Mode Base Clock Select */ +#define CCR2_BGDM BIT(4) /* Baud Rate Generator Double-Speed Mode Select */ + +/* CCR3 (Common Control Register 3) */ +#define CCR3_INIT 0x1203 +#define CCR3_BLK BIT(29) /* Block Transfer Mode */ +#define CCR3_GM BIT(28) /* GSM Mode */ +#define CCR3_CKE1 BIT(25) /* Clock Enable 1 */ +#define CCR3_CKE0 BIT(24) /* Clock Enable 0 */ +#define CCR3_DEN BIT(21) /* Driver Enabled */ +#define CCR3_FM BIT(20) /* FIFO Mode Select */ +#define CCR3_MP BIT(19) /* Multi-Processor Mode */ +#define CCR3_MOD_ASYNC 0 /* Asynchronous mode (Multi-processor mode) */ +#define CCR3_MOD_IRDA BIT(16) /* Smart card interface mode */ +#define CCR3_MOD_CLK_SYNC BIT(17) /* Clock synchronous mode */ +#define CCR3_MOD_SPI (BIT(17) | BIT(16)) /* Simple SPI mode */ +#define CCR3_MOD_I2C BIT(18) /* Simple I2C mode */ +#define CCR3_RXDESEL BIT(15) /* Asynchronous Start Bit Edge Detection Select */ +#define CCR3_STP BIT(14) /* Stop bit Length */ +#define CCR3_SINV BIT(13) /* Transmitted/Received Data Invert */ +#define CCR3_LSBF BIT(12) /* LSB First select */ +#define CCR3_CHR1 BIT(9) /* Character Length */ +#define CCR3_CHR0 BIT(8) /* Character Length */ +#define CCR3_BPEN BIT(7) /* Synchronizer Bypass Enable */ +#define CCR3_CPOL BIT(1) /* Clock Polarity Select */ +#define CCR3_CPHA BIT(0) /* Clock Phase Select */ + /* FCR (FIFO Control Register) */ #define FCR_RFRST BIT(23) /* Receive FIFO Data Register Reset */ #define FCR_TFRST BIT(15) /* Transmit FIFO Data Register Reset */ @@ -138,6 +175,29 @@ static void rsci_start_rx(struct uart_port *port) rsci_serial_out(port, CCR0, ctrl); } +static void rsci_enable_ms(struct uart_port *port) +{ + mctrl_gpio_enable_ms(to_sci_port(port)->gpios); +} + +static void rsci_init_pins(struct uart_port *port, unsigned int cflag) +{ + struct sci_port *s = to_sci_port(port); + + /* Use port-specific handler if provided */ + if (s->cfg->ops && s->cfg->ops->init_pins) { + s->cfg->ops->init_pins(port, cflag); + return; + } + + if (!s->has_rtscts) + return; + + if (s->autorts) + rsci_serial_out(port, CCR1, rsci_serial_in(port, CCR1) | + CCR1_CTSE | CCR1_CTSPEN); +} + static int rsci_scif_set_rtrg(struct uart_port *port, int rx_trig) { u32 fcr = rsci_serial_in(port, FCR); @@ -157,18 +217,119 @@ static int rsci_scif_set_rtrg(struct uart_port *port, int rx_trig) static void rsci_set_termios(struct uart_port *port, struct ktermios *termios, const struct ktermios *old) { + unsigned int ccr2_val = CCR2_INIT, ccr3_val = CCR3_INIT; + unsigned int ccr0_val = 0, ccr1_val = 0, ccr4_val = 0; + unsigned int brr1 = 255, cks1 = 0, srr1 = 15; struct sci_port *s = to_sci_port(port); + unsigned int brr = 255, cks = 0; + int min_err = INT_MAX, err; + unsigned long max_freq = 0; + unsigned int baud, i; unsigned long flags; + unsigned int ctrl; + int best_clk = -1; + + if ((termios->c_cflag & CSIZE) == CS7) { + ccr3_val |= CCR3_CHR0; + } else { + termios->c_cflag &= ~CSIZE; + termios->c_cflag |= CS8; + } + + if (termios->c_cflag & PARENB) + ccr1_val |= CCR1_PE; + + if (termios->c_cflag & PARODD) + ccr1_val |= (CCR1_PE | CCR1_PM); + + if (termios->c_cflag & CSTOPB) + ccr3_val |= CCR3_STP; + + /* Enable noise filter function */ + ccr1_val |= CCR1_NFEN; + + /* + * earlyprintk comes here early on with port->uartclk set to zero. + * the clock framework is not up and running at this point so here + * we assume that 115200 is the maximum baud rate. please note that + * the baud rate is not programmed during earlyprintk - it is assumed + * that the previous boot loader has enabled required clocks and + * setup the baud rate generator hardware for us already. + */ + if (!port->uartclk) { + max_freq = 115200; + } else { + for (i = 0; i < SCI_NUM_CLKS; i++) + max_freq = max(max_freq, s->clk_rates[i]); + + max_freq /= min_sr(s); + } + + baud = uart_get_baud_rate(port, termios, old, 0, max_freq); + if (!baud) + goto done; + + /* Divided Functional Clock using standard Bit Rate Register */ + err = sci_scbrr_calc(s, baud, &brr1, &srr1, &cks1); + if (abs(err) < abs(min_err)) { + best_clk = SCI_FCK; + ccr0_val = 0; + min_err = err; + brr = brr1; + cks = cks1; + } + +done: + if (best_clk >= 0) + dev_dbg(port->dev, "Using clk %pC for %u%+d bps\n", + s->clks[best_clk], baud, min_err); sci_port_enable(s); uart_port_lock_irqsave(port, &flags); - /* For now, only RX enabling is supported */ - if (termios->c_cflag & CREAD) + uart_update_timeout(port, termios->c_cflag, baud); + + rsci_serial_out(port, CCR0, ccr0_val); + + ccr3_val |= CCR3_FM; + rsci_serial_out(port, CCR3, ccr3_val); + + ccr2_val |= (cks << 20) | (brr << 8); + rsci_serial_out(port, CCR2, ccr2_val); + + rsci_serial_out(port, CCR1, ccr1_val); + rsci_serial_out(port, CCR4, ccr4_val); + + ctrl = rsci_serial_in(port, FCR); + ctrl |= (FCR_RFRST | FCR_TFRST); + rsci_serial_out(port, FCR, ctrl); + + if (s->rx_trigger > 1) + rsci_scif_set_rtrg(port, s->rx_trigger); + + port->status &= ~UPSTAT_AUTOCTS; + s->autorts = false; + + if ((port->flags & UPF_HARD_FLOW) && (termios->c_cflag & CRTSCTS)) { + port->status |= UPSTAT_AUTOCTS; + s->autorts = true; + } + + rsci_init_pins(port, termios->c_cflag); + rsci_serial_out(port, CFCLR, CFCLR_CLRFLAG); + rsci_serial_out(port, FFCLR, FFCLR_DRC); + + ccr0_val |= CCR0_RE; + rsci_serial_out(port, CCR0, ccr0_val); + + if ((termios->c_cflag & CREAD) != 0) rsci_start_rx(port); uart_port_unlock_irqrestore(port, flags); sci_port_disable(s); + + if (UART_ENABLE_MS(port, termios->c_cflag)) + rsci_enable_ms(port); } static int rsci_txfill(struct uart_port *port) @@ -193,13 +354,34 @@ static unsigned int rsci_tx_empty(struct uart_port *port) static void rsci_set_mctrl(struct uart_port *port, unsigned int mctrl) { - /* Not supported yet */ + if (mctrl & TIOCM_LOOP) { + /* Standard loopback mode */ + rsci_serial_out(port, CCR1, rsci_serial_in(port, CCR1) | CCR1_SPLP); + } } static unsigned int rsci_get_mctrl(struct uart_port *port) { - /* Not supported yet */ - return 0; + struct sci_port *s = to_sci_port(port); + struct mctrl_gpios *gpios = s->gpios; + unsigned int mctrl = 0; + + mctrl_gpio_get(gpios, &mctrl); + + /* + * CTS/RTS is handled in hardware when supported, while nothing + * else is wired up. + */ + if (!mctrl_gpio_to_gpiod(gpios, UART_GPIO_CTS)) + mctrl |= TIOCM_CTS; + + if (!mctrl_gpio_to_gpiod(gpios, UART_GPIO_DSR)) + mctrl |= TIOCM_DSR; + + if (!mctrl_gpio_to_gpiod(gpios, UART_GPIO_DCD)) + mctrl |= TIOCM_CAR; + + return mctrl; } static void rsci_clear_CFC(struct uart_port *port, unsigned int mask) @@ -329,7 +511,8 @@ static void rsci_receive_chars(struct uart_port *port) continue; } - /* Store data and status. + /* + * Store data and status. * Non FIFO mode is not supported */ if (rdat & RDR_FFER) { @@ -363,6 +546,28 @@ static void rsci_receive_chars(struct uart_port *port) } } +static void rsci_break_ctl(struct uart_port *port, int break_state) +{ + unsigned short ccr0_val, ccr1_val; + unsigned long flags; + + uart_port_lock_irqsave(port, &flags); + ccr1_val = rsci_serial_in(port, CCR1); + ccr0_val = rsci_serial_in(port, CCR0); + + if (break_state == -1) { + ccr1_val = (ccr1_val | CCR1_SPB2IO) & ~CCR1_SPB2DT; + ccr0_val &= ~CCR0_TE; + } else { + ccr1_val = (ccr1_val | CCR1_SPB2DT) & ~CCR1_SPB2IO; + ccr0_val |= CCR0_TE; + } + + rsci_serial_out(port, CCR1, ccr1_val); + rsci_serial_out(port, CCR0, ccr0_val); + uart_port_unlock_irqrestore(port, flags); +} + static void rsci_poll_put_char(struct uart_port *port, unsigned char c) { u32 status; @@ -384,12 +589,21 @@ done: static void rsci_prepare_console_write(struct uart_port *port, u32 ctrl) { struct sci_port *s = to_sci_port(port); - u32 ctrl_temp = - s->params->param_bits->rxtx_enable | CCR0_TIE | - s->hscif_tot; + u32 ctrl_temp = s->params->param_bits->rxtx_enable; + + if (s->type == RSCI_PORT_SCIF16) + ctrl_temp |= CCR0_TIE | s->hscif_tot; + rsci_serial_out(port, CCR0, ctrl_temp); } +static void rsci_finish_console_write(struct uart_port *port, u32 ctrl) +{ + /* First set TE = 0 and then restore the CCR0 value */ + rsci_serial_out(port, CCR0, ctrl & ~CCR0_TE); + rsci_serial_out(port, CCR0, ctrl); +} + static const char *rsci_type(struct uart_port *port) { return "rsci"; @@ -419,6 +633,17 @@ static const struct sci_port_params_bits rsci_port_param_bits = { .poll_sent_bits = CSR_TDRE | CSR_TEND, }; +static const struct sci_port_params rsci_rzg3e_port_params = { + .fifosize = 32, + .overrun_reg = CSR, + .overrun_mask = CSR_ORER, + .sampling_rate_mask = SCI_SR(32), + .error_mask = RSCI_DEFAULT_ERROR_MASK, + .error_clear = RSCI_ERROR_CLEAR, + .param_bits = &rsci_port_param_bits, + .common_regs = &rsci_common_regs, +}; + static const struct sci_port_params rsci_rzt2h_port_params = { .fifosize = 16, .overrun_reg = CSR, @@ -437,6 +662,8 @@ static const struct uart_ops rsci_uart_ops = { .start_tx = rsci_start_tx, .stop_tx = rsci_stop_tx, .stop_rx = rsci_stop_rx, + .enable_ms = rsci_enable_ms, + .break_ctl = rsci_break_ctl, .startup = sci_startup, .shutdown = sci_shutdown, .set_termios = rsci_set_termios, @@ -456,11 +683,19 @@ static const struct sci_port_ops rsci_port_ops = { .receive_chars = rsci_receive_chars, .poll_put_char = rsci_poll_put_char, .prepare_console_write = rsci_prepare_console_write, + .finish_console_write = rsci_finish_console_write, .suspend_regs_size = rsci_suspend_regs_size, .set_rtrg = rsci_scif_set_rtrg, .shutdown_complete = rsci_shutdown_complete, }; +struct sci_of_data of_rsci_rzg3e_data = { + .type = RSCI_PORT_SCIF32, + .ops = &rsci_port_ops, + .uart_ops = &rsci_uart_ops, + .params = &rsci_rzg3e_port_params, +}; + struct sci_of_data of_rsci_rzt2h_data = { .type = RSCI_PORT_SCIF16, .ops = &rsci_port_ops, @@ -470,12 +705,19 @@ struct sci_of_data of_rsci_rzt2h_data = { #ifdef CONFIG_SERIAL_SH_SCI_EARLYCON +static int __init rsci_rzg3e_early_console_setup(struct earlycon_device *device, + const char *opt) +{ + return scix_early_console_setup(device, &of_rsci_rzg3e_data); +} + static int __init rsci_rzt2h_early_console_setup(struct earlycon_device *device, const char *opt) { return scix_early_console_setup(device, &of_rsci_rzt2h_data); } +OF_EARLYCON_DECLARE(rsci, "renesas,r9a09g047-rsci", rsci_rzg3e_early_console_setup); OF_EARLYCON_DECLARE(rsci, "renesas,r9a09g077-rsci", rsci_rzt2h_early_console_setup); #endif /* CONFIG_SERIAL_SH_SCI_EARLYCON */ diff --git a/drivers/tty/serial/rsci.h b/drivers/tty/serial/rsci.h index 9547148e8bd1..2aa2ba3973ee 100644 --- a/drivers/tty/serial/rsci.h +++ b/drivers/tty/serial/rsci.h @@ -5,6 +5,7 @@ #include "sh-sci-common.h" +extern struct sci_of_data of_rsci_rzg3e_data; extern struct sci_of_data of_rsci_rzt2h_data; #endif /* __RSCI_H__ */ diff --git a/drivers/tty/serial/sh-sci.c b/drivers/tty/serial/sh-sci.c index 677293115f1e..a75d2113752b 100644 --- a/drivers/tty/serial/sh-sci.c +++ b/drivers/tty/serial/sh-sci.c @@ -3329,6 +3329,7 @@ static int sci_init_single(struct platform_device *dev, sci_port->rx_trigger = 64; break; case PORT_SCIFA: + case RSCI_PORT_SCIF32: sci_port->rx_trigger = 32; break; case PORT_SCIF: @@ -3662,6 +3663,10 @@ static const struct of_device_id of_sci_match[] __maybe_unused = { .data = &of_sci_scif_rzv2h, }, #ifdef CONFIG_SERIAL_RSCI + { + .compatible = "renesas,r9a09g047-rsci", + .data = &of_rsci_rzg3e_data, + }, { .compatible = "renesas,r9a09g077-rsci", .data = &of_rsci_rzt2h_data, -- 2.47.3