From d635711daa98be86d4c7fd01499c34f566b54ccb Mon Sep 17 00:00:00 2001 From: André Fabian Silva Delgado Date: Fri, 10 Jun 2016 05:30:17 -0300 Subject: Linux-libre 4.6.2-gnu --- drivers/tty/serial/sh-sci.c | 178 ++++++++++++++++++++++++++++++++------------ 1 file changed, 129 insertions(+), 49 deletions(-) (limited to 'drivers/tty/serial/sh-sci.c') diff --git a/drivers/tty/serial/sh-sci.c b/drivers/tty/serial/sh-sci.c index 4646a9f53..0130feb06 100644 --- a/drivers/tty/serial/sh-sci.c +++ b/drivers/tty/serial/sh-sci.c @@ -84,6 +84,22 @@ enum SCI_CLKS { SCI_NUM_CLKS }; +/* Bit x set means sampling rate x + 1 is supported */ +#define SCI_SR(x) BIT((x) - 1) +#define SCI_SR_RANGE(x, y) GENMASK((y) - 1, (x) - 1) + +#define SCI_SR_SCIFAB SCI_SR(5) | SCI_SR(7) | SCI_SR(11) | \ + SCI_SR(13) | SCI_SR(16) | SCI_SR(17) | \ + SCI_SR(19) | SCI_SR(27) + +#define min_sr(_port) ffs((_port)->sampling_rate_mask) +#define max_sr(_port) fls((_port)->sampling_rate_mask) + +/* Iterate over all supported sampling rates, from high to low */ +#define for_each_sr(_sr, _port) \ + for ((_sr) = max_sr(_port); (_sr) >= min_sr(_port); (_sr)--) \ + if ((_port)->sampling_rate_mask & SCI_SR((_sr))) + struct sci_port { struct uart_port port; @@ -93,7 +109,7 @@ struct sci_port { unsigned int overrun_mask; unsigned int error_mask; unsigned int error_clear; - unsigned int sampling_rate; + unsigned int sampling_rate_mask; resource_size_t reg_size; /* Break timer */ @@ -637,7 +653,8 @@ static void sci_clear_SCxSR(struct uart_port *port, unsigned int mask) } } -#if defined(CONFIG_CONSOLE_POLL) || defined(CONFIG_SERIAL_SH_SCI_CONSOLE) +#if defined(CONFIG_CONSOLE_POLL) || defined(CONFIG_SERIAL_SH_SCI_CONSOLE) || \ + defined(CONFIG_SERIAL_SH_SCI_EARLYCON) #ifdef CONFIG_CONSOLE_POLL static int sci_poll_get_char(struct uart_port *port) @@ -678,7 +695,8 @@ static void sci_poll_put_char(struct uart_port *port, unsigned char c) serial_port_out(port, SCxTDR, c); sci_clear_SCxSR(port, SCxSR_TDxE_CLEAR(port) & ~SCxSR_TEND(port)); } -#endif /* CONFIG_CONSOLE_POLL || CONFIG_SERIAL_SH_SCI_CONSOLE */ +#endif /* CONFIG_CONSOLE_POLL || CONFIG_SERIAL_SH_SCI_CONSOLE || + CONFIG_SERIAL_SH_SCI_EARLYCON */ static void sci_init_pins(struct uart_port *port, unsigned int cflag) { @@ -1902,19 +1920,13 @@ static int sci_sck_calc(struct sci_port *s, unsigned int bps, unsigned int *srr) { unsigned long freq = s->clk_rates[SCI_SCK]; - unsigned int min_sr, max_sr, sr; int err, min_err = INT_MAX; + unsigned int sr; - if (s->sampling_rate) { - /* SCI(F) has a fixed sampling rate */ - min_sr = max_sr = s->sampling_rate / 2; - } else { - /* HSCIF has a variable 1/(8..32) sampling rate */ - min_sr = 8; - max_sr = 32; - } + if (s->port.type != PORT_HSCIF) + freq *= 2; - for (sr = max_sr; sr >= min_sr; sr--) { + for_each_sr(sr, s) { err = DIV_ROUND_CLOSEST(freq, sr) - bps; if (abs(err) >= abs(min_err)) continue; @@ -1935,19 +1947,13 @@ static int sci_brg_calc(struct sci_port *s, unsigned int bps, unsigned long freq, unsigned int *dlr, unsigned int *srr) { - unsigned int min_sr, max_sr, sr, dl; int err, min_err = INT_MAX; + unsigned int sr, dl; - if (s->sampling_rate) { - /* SCIF has a fixed sampling rate */ - min_sr = max_sr = s->sampling_rate / 2; - } else { - /* HSCIF has a variable 1/(8..32) sampling rate */ - min_sr = 8; - max_sr = 32; - } + if (s->port.type != PORT_HSCIF) + freq *= 2; - for (sr = max_sr; sr >= min_sr; sr--) { + for_each_sr(sr, s) { dl = DIV_ROUND_CLOSEST(freq, sr * bps); dl = clamp(dl, 1U, 65535U); @@ -1973,19 +1979,12 @@ static int sci_scbrr_calc(struct sci_port *s, unsigned int bps, unsigned int *brr, unsigned int *srr, unsigned int *cks) { - unsigned int min_sr, max_sr, shift, sr, br, prediv, scrate, c; unsigned long freq = s->clk_rates[SCI_FCK]; + unsigned int sr, br, prediv, scrate, c; int err, min_err = INT_MAX; - if (s->sampling_rate) { - min_sr = max_sr = s->sampling_rate; - shift = 0; - } else { - /* HSCIF has a variable sample rate */ - min_sr = 8; - max_sr = 32; - shift = 1; - } + if (s->port.type != PORT_HSCIF) + freq *= 2; /* * Find the combination of sample rate and clock select with the @@ -2002,10 +2001,10 @@ static int sci_scbrr_calc(struct sci_port *s, unsigned int bps, * (|D - 0.5| / N * (1 + F))| * NOTE: Usually, treat D for 0.5, F is 0 by this calculation. */ - for (sr = max_sr; sr >= min_sr; sr--) { + for_each_sr(sr, s) { for (c = 0; c <= 3; c++) { /* integerized formulas from HSCIF documentation */ - prediv = sr * (1 << (2 * c + shift)); + prediv = sr * (1 << (2 * c + 1)); /* * We need to calculate: @@ -2062,7 +2061,7 @@ static void sci_reset(struct uart_port *port) static void sci_set_termios(struct uart_port *port, struct ktermios *termios, struct ktermios *old) { - unsigned int baud, smr_val = 0, scr_val = 0, i; + unsigned int baud, smr_val = SCSMR_ASYNC, scr_val = 0, i; unsigned int brr = 255, cks = 0, srr = 15, dl = 0, sccks = 0; unsigned int brr1 = 255, cks1 = 0, srr1 = 15, dl1 = 0; struct sci_port *s = to_sci_port(port); @@ -2096,8 +2095,7 @@ static void sci_set_termios(struct uart_port *port, struct ktermios *termios, for (i = 0; i < SCI_NUM_CLKS; i++) max_freq = max(max_freq, s->clk_rates[i]); - baud = uart_get_baud_rate(port, termios, old, 0, - max_freq / max(s->sampling_rate, 8U)); + baud = uart_get_baud_rate(port, termios, old, 0, max_freq / min_sr(s)); if (!baud) goto done; @@ -2185,6 +2183,17 @@ done: uart_update_timeout(port, termios->c_cflag, baud); if (best_clk >= 0) { + if (port->type == PORT_SCIFA || port->type == PORT_SCIFB) + switch (srr + 1) { + case 5: smr_val |= SCSMR_SRC_5; break; + case 7: smr_val |= SCSMR_SRC_7; break; + case 11: smr_val |= SCSMR_SRC_11; break; + case 13: smr_val |= SCSMR_SRC_13; break; + case 16: smr_val |= SCSMR_SRC_16; break; + case 17: smr_val |= SCSMR_SRC_17; break; + case 19: smr_val |= SCSMR_SRC_19; break; + case 27: smr_val |= SCSMR_SRC_27; break; + } smr_val |= cks; dev_dbg(port->dev, "SCR 0x%x SMR 0x%x BRR %u CKS 0x%x DL %u SRR %u\n", @@ -2200,7 +2209,8 @@ done: } else { /* Don't touch the bit rate configuration */ scr_val = s->cfg->scscr & (SCSCR_CKE1 | SCSCR_CKE0); - smr_val |= serial_port_in(port, SCSMR) & SCSMR_CKS; + smr_val |= serial_port_in(port, SCSMR) & + (SCSMR_CKEDG | SCSMR_SRC_MASK | SCSMR_CKS); dev_dbg(port->dev, "SCR 0x%x SMR 0x%x\n", scr_val, smr_val); serial_port_out(port, SCSCR, scr_val); serial_port_out(port, SCSMR, smr_val); @@ -2232,6 +2242,16 @@ done: scr_val |= s->cfg->scscr & ~(SCSCR_CKE1 | SCSCR_CKE0); dev_dbg(port->dev, "SCSCR 0x%x\n", scr_val); serial_port_out(port, SCSCR, scr_val); + if ((srr + 1 == 5) && + (port->type == PORT_SCIFA || port->type == PORT_SCIFB)) { + /* + * In asynchronous mode, when the sampling rate is 1/5, first + * received data may become invalid on some SCIFA and SCIFB. + * To avoid this problem wait more than 1 serial data time (1 + * bit time x serial data number) after setting SCSCR.RE = 1. + */ + udelay(DIV_ROUND_UP(10 * 1000000, baud)); + } #ifdef CONFIG_SERIAL_SH_SCI_DMA /* @@ -2528,37 +2548,37 @@ static int sci_init_single(struct platform_device *dev, port->fifosize = 256; sci_port->overrun_reg = SCxSR; sci_port->overrun_mask = SCIFA_ORER; - sci_port->sampling_rate = 16; + sci_port->sampling_rate_mask = SCI_SR_SCIFAB; break; case PORT_HSCIF: port->fifosize = 128; sci_port->overrun_reg = SCLSR; sci_port->overrun_mask = SCLSR_ORER; - sci_port->sampling_rate = 0; + sci_port->sampling_rate_mask = SCI_SR_RANGE(8, 32); break; case PORT_SCIFA: port->fifosize = 64; sci_port->overrun_reg = SCxSR; sci_port->overrun_mask = SCIFA_ORER; - sci_port->sampling_rate = 16; + sci_port->sampling_rate_mask = SCI_SR_SCIFAB; break; case PORT_SCIF: port->fifosize = 16; if (p->regtype == SCIx_SH7705_SCIF_REGTYPE) { sci_port->overrun_reg = SCxSR; sci_port->overrun_mask = SCIFA_ORER; - sci_port->sampling_rate = 16; + sci_port->sampling_rate_mask = SCI_SR(16); } else { sci_port->overrun_reg = SCLSR; sci_port->overrun_mask = SCLSR_ORER; - sci_port->sampling_rate = 32; + sci_port->sampling_rate_mask = SCI_SR(32); } break; default: port->fifosize = 1; sci_port->overrun_reg = SCxSR; sci_port->overrun_mask = SCI_ORER; - sci_port->sampling_rate = 32; + sci_port->sampling_rate_mask = SCI_SR(32); break; } @@ -2567,7 +2587,7 @@ static int sci_init_single(struct platform_device *dev, * data override the sampling rate for now. */ if (p->sampling_rate) - sci_port->sampling_rate = p->sampling_rate; + sci_port->sampling_rate_mask = SCI_SR(p->sampling_rate); if (!early) { ret = sci_init_clocks(sci_port, &dev->dev); @@ -2632,7 +2652,8 @@ static void sci_cleanup_single(struct sci_port *port) pm_runtime_disable(port->port.dev); } -#ifdef CONFIG_SERIAL_SH_SCI_CONSOLE +#if defined(CONFIG_SERIAL_SH_SCI_CONSOLE) || \ + defined(CONFIG_SERIAL_SH_SCI_EARLYCON) static void serial_console_putchar(struct uart_port *port, int ch) { sci_poll_put_char(port, ch); @@ -2652,9 +2673,12 @@ static void serial_console_write(struct console *co, const char *s, int locked = 1; local_irq_save(flags); +#if defined(SUPPORT_SYSRQ) if (port->sysrq) locked = 0; - else if (oops_in_progress) + else +#endif + if (oops_in_progress) locked = spin_trylock(&port->lock); else spin_lock(&port->lock); @@ -2764,7 +2788,7 @@ static inline int sci_probe_earlyprintk(struct platform_device *pdev) #define SCI_CONSOLE NULL -#endif /* CONFIG_SERIAL_SH_SCI_CONSOLE */ +#endif /* CONFIG_SERIAL_SH_SCI_CONSOLE || CONFIG_SERIAL_SH_SCI_EARLYCON */ static const char banner[] __initconst = "SuperH (H)SCI(F) driver initialized"; @@ -2998,6 +3022,62 @@ static void __exit sci_exit(void) early_platform_init_buffer("earlyprintk", &sci_driver, early_serial_buf, ARRAY_SIZE(early_serial_buf)); #endif +#ifdef CONFIG_SERIAL_SH_SCI_EARLYCON +static struct __init plat_sci_port port_cfg; + +static int __init early_console_setup(struct earlycon_device *device, + int type) +{ + if (!device->port.membase) + return -ENODEV; + + device->port.serial_in = sci_serial_in; + device->port.serial_out = sci_serial_out; + device->port.type = type; + memcpy(&sci_ports[0].port, &device->port, sizeof(struct uart_port)); + sci_ports[0].cfg = &port_cfg; + sci_ports[0].cfg->type = type; + sci_probe_regmap(sci_ports[0].cfg); + port_cfg.scscr = sci_serial_in(&sci_ports[0].port, SCSCR) | + SCSCR_RE | SCSCR_TE; + sci_serial_out(&sci_ports[0].port, SCSCR, port_cfg.scscr); + + device->con->write = serial_console_write; + return 0; +} +static int __init sci_early_console_setup(struct earlycon_device *device, + const char *opt) +{ + return early_console_setup(device, PORT_SCI); +} +static int __init scif_early_console_setup(struct earlycon_device *device, + const char *opt) +{ + return early_console_setup(device, PORT_SCIF); +} +static int __init scifa_early_console_setup(struct earlycon_device *device, + const char *opt) +{ + return early_console_setup(device, PORT_SCIFA); +} +static int __init scifb_early_console_setup(struct earlycon_device *device, + const char *opt) +{ + return early_console_setup(device, PORT_SCIFB); +} +static int __init hscif_early_console_setup(struct earlycon_device *device, + const char *opt) +{ + return early_console_setup(device, PORT_HSCIF); +} + +OF_EARLYCON_DECLARE(sci, "renesas,sci", sci_early_console_setup); +OF_EARLYCON_DECLARE(scif, "renesas,scif", scif_early_console_setup); +OF_EARLYCON_DECLARE(scifa, "renesas,scifa", scifa_early_console_setup); +OF_EARLYCON_DECLARE(scifb, "renesas,scifb", scifb_early_console_setup); +OF_EARLYCON_DECLARE(hscif, "renesas,hscif", hscif_early_console_setup); +#endif /* CONFIG_SERIAL_SH_SCI_EARLYCON */ + module_init(sci_init); module_exit(sci_exit); -- cgit v1.2.3-54-g00ecf