serial: sh-sci: increase RX FIFO trigger defaults for (H)SCIF

Sets reasonable trigger defaults for the various SCIF variants.
Also corrects the FIFO size for SH7705-style ports.

Signed-off-by: Ulrich Hecht <ulrich.hecht+renesas@gmail.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/tty/serial/sh-sci.c b/drivers/tty/serial/sh-sci.c
index 050d028cf2a15dbb9b324dd8d4e9bcc1978857ef..520e344a811df2c4f3bf109ccf8cd78390b468c7 100644 (file)
--- a/drivers/tty/serial/sh-sci.c
+++ b/drivers/tty/serial/sh-sci.c
@@ -148,6 +148,7 @@ struct sci_port {
        struct timer_list               rx_timer;
        unsigned int                    rx_timeout;
 #endif
+       int                             rx_trigger;
 
        bool has_rtscts;
        bool autorts;
@@ -450,7 +451,7 @@ static const struct sci_port_params sci_port_params[SCIx_NR_REGTYPES] = {
                        [SCFCR]         = { 0x18, 16 },
                        [SCFDR]         = { 0x1c, 16 },
                },
-               .fifosize = 16,
+               .fifosize = 64,
                .overrun_reg = SCxSR,
                .overrun_mask = SCIFA_ORER,
                .sampling_rate_mask = SCI_SR(16),
@@ -2062,6 +2063,7 @@ static void sci_reset(struct uart_port *port)
 {
        const struct plat_sci_reg *reg;
        unsigned int status;
+       struct sci_port *s = to_sci_port(port);
 
        do {
                status = serial_port_in(port, SCxSR);
@@ -2081,6 +2083,9 @@ static void sci_reset(struct uart_port *port)
                status &= ~(SCLSR_TO | SCLSR_ORER);
                serial_port_out(port, SCLSR, status);
        }
+
+       if (s->rx_trigger > 1)
+               scif_set_rtrg(port, s->rx_trigger);
 }
 
 static void sci_set_termios(struct uart_port *port, struct ktermios *termios,
@@ -2615,6 +2620,28 @@ static int sci_init_single(struct platform_device *dev,
        if (unlikely(sci_port->params == NULL))
                return -EINVAL;
 
+       switch (p->type) {
+       case PORT_SCIFB:
+               sci_port->rx_trigger = 48;
+               break;
+       case PORT_HSCIF:
+               sci_port->rx_trigger = 64;
+               break;
+       case PORT_SCIFA:
+               sci_port->rx_trigger = 32;
+               break;
+       case PORT_SCIF:
+               if (p->regtype == SCIx_SH7705_SCIF_REGTYPE)
+                       /* RX triggering not implemented for this IP */
+                       sci_port->rx_trigger = 1;
+               else
+                       sci_port->rx_trigger = 8;
+               break;
+       default:
+               sci_port->rx_trigger = 1;
+               break;
+       }
+
        /* SCIFA on sh7723 and sh7724 need a custom sampling rate that doesn't
         * match the SoC datasheet, this should be investigated. Let platform
         * data override the sampling rate for now.