[PATCH v10 01/10] dt-bindings: serial: Added secondary clock for RZ/T2H RSCI

[PATCH v10 01/10] dt-bindings: serial: Added secondary clock for RZ/T2H RSCI

[Thierry Bultel]

At boot, the default clock is the PCLKM core clock (synchronous
clock, which is enabled by the bootloader).
For different baudrates, the asynchronous clock input must be used.
Clock selection is made by an internal register of RCSI.

Add the optional "sck", external clock input.

Also remove the unneeded serial0 alias from the dts example.

Signed-off-by: Thierry Bultel <thierry.bultel.yh@bp.renesas.com>
---
Changes v9->v10:
 - mention sck in description
 - no maxItems on clock-names
 - fixed the #include dependency in dts example
Changes v8->v9:
 - typo in description
 - named clocks 'operational' and 'bus', and added optional 'sck' clock
 - uses value of 2nd core clock in example to break the dependency on cpg patch
---
 .../bindings/serial/renesas,rsci.yaml           | 17 +++++++++--------
 1 file changed, 9 insertions(+), 8 deletions(-)

diff --git a/Documentation/devicetree/bindings/serial/renesas,rsci.yaml b/Documentation/devicetree/bindings/serial/renesas,rsci.yaml
index ea879db5f485..1bf255407df0 100644
--- a/Documentation/devicetree/bindings/serial/renesas,rsci.yaml
+++ b/Documentation/devicetree/bindings/serial/renesas,rsci.yaml
@@ -35,10 +35,15 @@ properties:
       - const: tei
 
   clocks:
-    maxItems: 1
+    minItems: 2
+    maxItems: 3
 
   clock-names:
-    const: fck # UART functional clock
+    minItems: 2
+    items:
+      - const: operation
+      - const: bus
+      - const: sck # optional external clock input
 
   power-domains:
     maxItems: 1
@@ -60,10 +65,6 @@ examples:
     #include <dt-bindings/interrupt-controller/arm-gic.h>
     #include <dt-bindings/clock/renesas-cpg-mssr.h>
 
-    aliases {
-        serial0 = &sci0;
-    };
-
     sci0: serial@80005000 {
         compatible = "renesas,r9a09g077-rsci";
         reg = <0x80005000 0x400>;
@@ -72,7 +73,7 @@ examples:
                      <GIC_SPI 592 IRQ_TYPE_EDGE_RISING>,
                      <GIC_SPI 593 IRQ_TYPE_LEVEL_HIGH>;
         interrupt-names = "eri", "rxi", "txi", "tei";
-        clocks = <&cpg CPG_MOD 108>;
-        clock-names = "fck";
+        clocks = <&cpg CPG_MOD 8>, <&cpg CPG_CORE 13>;
+        clock-names = "operation", "bus";
         power-domains = <&cpg>;
     };
-- 
2.43.0

Re: [PATCH v10 01/10] dt-bindings: serial: Added secondary clock for RZ/T2H RSCI

[Geert Uytterhoeven]

On Fri, 23 May 2025 at 16:24, Thierry Bultel
<thierry.bultel.yh@bp.renesas.com> wrote:
> At boot, the default clock is the PCLKM core clock (synchronous
> clock, which is enabled by the bootloader).
> For different baudrates, the asynchronous clock input must be used.
> Clock selection is made by an internal register of RCSI.
>
> Add the optional "sck", external clock input.
>
> Also remove the unneeded serial0 alias from the dts example.
>
> Signed-off-by: Thierry Bultel <thierry.bultel.yh@bp.renesas.com>
> ---
> Changes v9->v10:
>  - mention sck in description
>  - no maxItems on clock-names
>  - fixed the #include dependency in dts example

Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>

Gr{oetje,eeting}s,

                        Geert

-- 
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds

Re: [PATCH v10 01/10] dt-bindings: serial: Added secondary clock for RZ/T2H RSCI

[Rob Herring]

On Fri, May 23, 2025 at 04:24:05PM +0200, Thierry Bultel wrote:
> At boot, the default clock is the PCLKM core clock (synchronous
> clock, which is enabled by the bootloader).
> For different baudrates, the asynchronous clock input must be used.
> Clock selection is made by an internal register of RCSI.
> 
> Add the optional "sck", external clock input.
> 
> Also remove the unneeded serial0 alias from the dts example.
> 
> Signed-off-by: Thierry Bultel <thierry.bultel.yh@bp.renesas.com>
> ---
> Changes v9->v10:
>  - mention sck in description
>  - no maxItems on clock-names
>  - fixed the #include dependency in dts example
> Changes v8->v9:
>  - typo in description
>  - named clocks 'operational' and 'bus', and added optional 'sck' clock
>  - uses value of 2nd core clock in example to break the dependency on cpg patch
> ---
>  .../bindings/serial/renesas,rsci.yaml           | 17 +++++++++--------
>  1 file changed, 9 insertions(+), 8 deletions(-)
> 
> diff --git a/Documentation/devicetree/bindings/serial/renesas,rsci.yaml b/Documentation/devicetree/bindings/serial/renesas,rsci.yaml
> index ea879db5f485..1bf255407df0 100644
> --- a/Documentation/devicetree/bindings/serial/renesas,rsci.yaml
> +++ b/Documentation/devicetree/bindings/serial/renesas,rsci.yaml
> @@ -35,10 +35,15 @@ properties:
>        - const: tei
>  
>    clocks:
> -    maxItems: 1
> +    minItems: 2
> +    maxItems: 3
>  
>    clock-names:
> -    const: fck # UART functional clock
> +    minItems: 2
> +    items:
> +      - const: operation
> +      - const: bus
> +      - const: sck # optional external clock input

You can't just change the clock names. What happens to users of 'fck'?

And you can't make additional entries required. What happens to users 
with only 1 clock defined?

Rob

Re: [PATCH v10 01/10] dt-bindings: serial: Added secondary clock for RZ/T2H RSCI

[Geert Uytterhoeven]

Hi Rob,

On Thu, 5 Jun 2025 at 16:39, Rob Herring <robh@kernel.org> wrote:
> On Fri, May 23, 2025 at 04:24:05PM +0200, Thierry Bultel wrote:
> > At boot, the default clock is the PCLKM core clock (synchronous
> > clock, which is enabled by the bootloader).
> > For different baudrates, the asynchronous clock input must be used.
> > Clock selection is made by an internal register of RCSI.
> >
> > Add the optional "sck", external clock input.
> >
> > Also remove the unneeded serial0 alias from the dts example.
> >
> > Signed-off-by: Thierry Bultel <thierry.bultel.yh@bp.renesas.com>
> > ---
> > Changes v9->v10:
> >  - mention sck in description
> >  - no maxItems on clock-names
> >  - fixed the #include dependency in dts example
> > Changes v8->v9:
> >  - typo in description
> >  - named clocks 'operational' and 'bus', and added optional 'sck' clock
> >  - uses value of 2nd core clock in example to break the dependency on cpg patch
> > ---
> >  .../bindings/serial/renesas,rsci.yaml           | 17 +++++++++--------
> >  1 file changed, 9 insertions(+), 8 deletions(-)
> >
> > diff --git a/Documentation/devicetree/bindings/serial/renesas,rsci.yaml b/Documentation/devicetree/bindings/serial/renesas,rsci.yaml
> > index ea879db5f485..1bf255407df0 100644
> > --- a/Documentation/devicetree/bindings/serial/renesas,rsci.yaml
> > +++ b/Documentation/devicetree/bindings/serial/renesas,rsci.yaml
> > @@ -35,10 +35,15 @@ properties:
> >        - const: tei
> >
> >    clocks:
> > -    maxItems: 1
> > +    minItems: 2
> > +    maxItems: 3
> >
> >    clock-names:
> > -    const: fck # UART functional clock
> > +    minItems: 2
> > +    items:
> > +      - const: operation
> > +      - const: bus
> > +      - const: sck # optional external clock input
>
> You can't just change the clock names. What happens to users of 'fck'?
>
> And you can't make additional entries required. What happens to users
> with only 1 clock defined?

There are no users of the bindings yet, and the RSCI driver updates haven't
reached linux-next yet.

Gr{oetje,eeting}s,

                        Geert

-- 
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds

[PATCH v10 06/10] serial: sh-sci: Use private port ID

[Thierry Bultel]

New port types cannot be added in serial_core.h, which is shared with
userspace.
In order to support new port types, the coming new ones will have
BIT(7) set in the id value, and in this case, uartport->type is
set to PORT_GENERIC.
This commit therefore changes all the places where the port type is
read, by not relying on uartport->type but on the private
value stored in struct sci_port.

Reviewed-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Thierry Bultel <thierry.bultel.yh@bp.renesas.com>
---
Changes v9->v10:
 - Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
 - Reviewed-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Changes v8->v9:
 - Shrunk length od type & regtype
 - Uses BIT(7) in id value
 - Set sci_ports[0].type & sci_ports[0].regtype in scix_early_console_setup
 drivers/tty/serial/sh-sci-common.h |   3 +
 drivers/tty/serial/sh-sci.c        | 159 ++++++++++++++++-------------
 2 files changed, 92 insertions(+), 70 deletions(-)

diff --git a/drivers/tty/serial/sh-sci-common.h b/drivers/tty/serial/sh-sci-common.h
index bd9d9cfac1c8..fcddf66780c9 100644
--- a/drivers/tty/serial/sh-sci-common.h
+++ b/drivers/tty/serial/sh-sci-common.h
@@ -142,6 +142,9 @@ struct sci_port {
 	int				rx_fifo_timeout;
 	u16				hscif_tot;
 
+	u8				type;
+	u8				regtype;
+
 	const struct sci_port_ops *ops;
 
 	bool has_rtscts;
diff --git a/drivers/tty/serial/sh-sci.c b/drivers/tty/serial/sh-sci.c
index ff1986dc6af3..be719c0db64a 100644
--- a/drivers/tty/serial/sh-sci.c
+++ b/drivers/tty/serial/sh-sci.c
@@ -75,6 +75,8 @@
 
 #define SCI_NPORTS CONFIG_SERIAL_SH_SCI_NR_UARTS
 
+#define SCI_PUBLIC_PORT_ID(port) (((port) & BIT(7)) ? PORT_GENERIC : (port))
+
 static struct sci_port sci_ports[SCI_NPORTS];
 static unsigned long sci_ports_in_use;
 static struct uart_driver sci_uart_driver;
@@ -580,7 +582,7 @@ static void sci_start_tx(struct uart_port *port)
 	unsigned short ctrl;
 
 #ifdef CONFIG_SERIAL_SH_SCI_DMA
-	if (port->type == PORT_SCIFA || port->type == PORT_SCIFB) {
+	if (s->type == PORT_SCIFA || s->type == PORT_SCIFB) {
 		u16 new, scr = sci_serial_in(port, SCSCR);
 		if (s->chan_tx)
 			new = scr | SCSCR_TDRQE;
@@ -592,7 +594,7 @@ static void sci_start_tx(struct uart_port *port)
 
 	if (s->chan_tx && !kfifo_is_empty(&port->state->port.xmit_fifo) &&
 	    dma_submit_error(s->cookie_tx)) {
-		if (s->cfg->regtype == SCIx_RZ_SCIFA_REGTYPE)
+		if (s->regtype == SCIx_RZ_SCIFA_REGTYPE)
 			/* Switch irq from SCIF to DMA */
 			disable_irq_nosync(s->irqs[SCIx_TXI_IRQ]);
 
@@ -601,8 +603,8 @@ static void sci_start_tx(struct uart_port *port)
 	}
 #endif
 
-	if (!s->chan_tx || s->cfg->regtype == SCIx_RZ_SCIFA_REGTYPE ||
-	    port->type == PORT_SCIFA || port->type == PORT_SCIFB) {
+	if (!s->chan_tx || s->regtype == SCIx_RZ_SCIFA_REGTYPE ||
+	    s->type == PORT_SCIFA || s->type == PORT_SCIFB) {
 		/* Set TIE (Transmit Interrupt Enable) bit in SCSCR */
 		ctrl = sci_serial_in(port, SCSCR);
 
@@ -611,7 +613,7 @@ static void sci_start_tx(struct uart_port *port)
 		 * (transmit interrupt enable) or in the same instruction to start
 		 * the transmit process.
 		 */
-		if (port->type == PORT_SCI)
+		if (s->type == PORT_SCI)
 			ctrl |= SCSCR_TE;
 
 		sci_serial_out(port, SCSCR, ctrl | SCSCR_TIE);
@@ -620,12 +622,13 @@ static void sci_start_tx(struct uart_port *port)
 
 static void sci_stop_tx(struct uart_port *port)
 {
+	struct sci_port *s = to_sci_port(port);
 	unsigned short ctrl;
 
 	/* Clear TIE (Transmit Interrupt Enable) bit in SCSCR */
 	ctrl = sci_serial_in(port, SCSCR);
 
-	if (port->type == PORT_SCIFA || port->type == PORT_SCIFB)
+	if (s->type == PORT_SCIFA || s->type == PORT_SCIFB)
 		ctrl &= ~SCSCR_TDRQE;
 
 	ctrl &= ~SCSCR_TIE;
@@ -633,21 +636,22 @@ static void sci_stop_tx(struct uart_port *port)
 	sci_serial_out(port, SCSCR, ctrl);
 
 #ifdef CONFIG_SERIAL_SH_SCI_DMA
-	if (to_sci_port(port)->chan_tx &&
-	    !dma_submit_error(to_sci_port(port)->cookie_tx)) {
-		dmaengine_terminate_async(to_sci_port(port)->chan_tx);
-		to_sci_port(port)->cookie_tx = -EINVAL;
+	if (s->chan_tx &&
+	    !dma_submit_error(s->cookie_tx)) {
+		dmaengine_terminate_async(s->chan_tx);
+		s->cookie_tx = -EINVAL;
 	}
 #endif
 }
 
 static void sci_start_rx(struct uart_port *port)
 {
+	struct sci_port *s = to_sci_port(port);
 	unsigned short ctrl;
 
 	ctrl = sci_serial_in(port, SCSCR) | port_rx_irq_mask(port);
 
-	if (port->type == PORT_SCIFA || port->type == PORT_SCIFB)
+	if (s->type == PORT_SCIFA || s->type == PORT_SCIFB)
 		ctrl &= ~SCSCR_RDRQE;
 
 	sci_serial_out(port, SCSCR, ctrl);
@@ -655,11 +659,12 @@ static void sci_start_rx(struct uart_port *port)
 
 static void sci_stop_rx(struct uart_port *port)
 {
+	struct sci_port *s = to_sci_port(port);
 	unsigned short ctrl;
 
 	ctrl = sci_serial_in(port, SCSCR);
 
-	if (port->type == PORT_SCIFA || port->type == PORT_SCIFB)
+	if (s->type == PORT_SCIFA || s->type == PORT_SCIFB)
 		ctrl &= ~SCSCR_RDRQE;
 
 	ctrl &= ~port_rx_irq_mask(port);
@@ -669,10 +674,12 @@ static void sci_stop_rx(struct uart_port *port)
 
 static void sci_clear_SCxSR(struct uart_port *port, unsigned int mask)
 {
-	if (port->type == PORT_SCI) {
+	struct sci_port *s = to_sci_port(port);
+
+	if (s->type == PORT_SCI) {
 		/* Just store the mask */
 		sci_serial_out(port, SCxSR, mask);
-	} else if (to_sci_port(port)->params->overrun_mask == SCIFA_ORER) {
+	} else if (s->params->overrun_mask == SCIFA_ORER) {
 		/* SCIFA/SCIFB and SCIF on SH7705/SH7720/SH7721 */
 		/* Only clear the status bits we want to clear */
 		sci_serial_out(port, SCxSR, sci_serial_in(port, SCxSR) & mask);
@@ -742,13 +749,13 @@ static void sci_init_pins(struct uart_port *port, unsigned int cflag)
 		return;
 	}
 
-	if (port->type == PORT_SCIFA || port->type == PORT_SCIFB) {
+	if (s->type == PORT_SCIFA || s->type == PORT_SCIFB) {
 		u16 data = sci_serial_in(port, SCPDR);
 		u16 ctrl = sci_serial_in(port, SCPCR);
 
 		/* Enable RXD and TXD pin functions */
 		ctrl &= ~(SCPCR_RXDC | SCPCR_TXDC);
-		if (to_sci_port(port)->has_rtscts) {
+		if (s->has_rtscts) {
 			/* RTS# is output, active low, unless autorts */
 			if (!(port->mctrl & TIOCM_RTS)) {
 				ctrl |= SCPCR_RTSC;
@@ -765,7 +772,7 @@ static void sci_init_pins(struct uart_port *port, unsigned int cflag)
 		}
 		sci_serial_out(port, SCPDR, data);
 		sci_serial_out(port, SCPCR, ctrl);
-	} else if (sci_getreg(port, SCSPTR)->size && s->cfg->regtype != SCIx_RZV2H_SCIF_REGTYPE) {
+	} else if (sci_getreg(port, SCSPTR)->size && s->regtype != SCIx_RZV2H_SCIF_REGTYPE) {
 		u16 status = sci_serial_in(port, SCSPTR);
 
 		/* RTS# is always output; and active low, unless autorts */
@@ -852,7 +859,7 @@ static void sci_transmit_chars(struct uart_port *port)
 			c = port->x_char;
 			port->x_char = 0;
 		} else if (stopped || !kfifo_get(&tport->xmit_fifo, &c)) {
-			if (port->type == PORT_SCI &&
+			if (s->type == PORT_SCI &&
 				   kfifo_is_empty(&tport->xmit_fifo)) {
 				ctrl = sci_serial_in(port, SCSCR);
 				ctrl &= ~SCSCR_TE;
@@ -873,7 +880,7 @@ static void sci_transmit_chars(struct uart_port *port)
 	if (kfifo_len(&tport->xmit_fifo) < WAKEUP_CHARS)
 		uart_write_wakeup(port);
 	if (kfifo_is_empty(&tport->xmit_fifo)) {
-		if (port->type == PORT_SCI) {
+		if (s->type == PORT_SCI) {
 			ctrl = sci_serial_in(port, SCSCR);
 			ctrl &= ~SCSCR_TIE;
 			ctrl |= SCSCR_TEIE;
@@ -904,7 +911,7 @@ static void sci_receive_chars(struct uart_port *port)
 		if (count == 0)
 			break;
 
-		if (port->type == PORT_SCI) {
+		if (s->type == PORT_SCI) {
 			char c = sci_serial_in(port, SCxRDR);
 			if (uart_handle_sysrq_char(port, c))
 				count = 0;
@@ -914,8 +921,8 @@ static void sci_receive_chars(struct uart_port *port)
 			for (i = 0; i < count; i++) {
 				char c;
 
-				if (port->type == PORT_SCIF ||
-				    port->type == PORT_HSCIF) {
+				if (s->type == PORT_SCIF ||
+				    s->type == PORT_HSCIF) {
 					status = sci_serial_in(port, SCxSR);
 					c = sci_serial_in(port, SCxRDR);
 				} else {
@@ -1052,6 +1059,7 @@ static int sci_handle_breaks(struct uart_port *port)
 
 static int scif_set_rtrg(struct uart_port *port, int rx_trig)
 {
+	struct sci_port *s = to_sci_port(port);
 	unsigned int bits;
 
 	if (rx_trig >= port->fifosize)
@@ -1065,7 +1073,7 @@ static int scif_set_rtrg(struct uart_port *port, int rx_trig)
 		return rx_trig;
 	}
 
-	switch (port->type) {
+	switch (s->type) {
 	case PORT_SCIF:
 		if (rx_trig < 4) {
 			bits = 0;
@@ -1150,7 +1158,7 @@ static ssize_t rx_fifo_trigger_store(struct device *dev,
 		return ret;
 
 	sci->rx_trigger = sci->ops->set_rtrg(port, r);
-	if (port->type == PORT_SCIFA || port->type == PORT_SCIFB)
+	if (sci->type == PORT_SCIFA || sci->type == PORT_SCIFB)
 		sci->ops->set_rtrg(port, 1);
 
 	return count;
@@ -1166,7 +1174,7 @@ static ssize_t rx_fifo_timeout_show(struct device *dev,
 	struct sci_port *sci = to_sci_port(port);
 	int v;
 
-	if (port->type == PORT_HSCIF)
+	if (sci->type == PORT_HSCIF)
 		v = sci->hscif_tot >> HSSCR_TOT_SHIFT;
 	else
 		v = sci->rx_fifo_timeout;
@@ -1188,7 +1196,7 @@ static ssize_t rx_fifo_timeout_store(struct device *dev,
 	if (ret)
 		return ret;
 
-	if (port->type == PORT_HSCIF) {
+	if (sci->type == PORT_HSCIF) {
 		if (r < 0 || r > 3)
 			return -EINVAL;
 		sci->hscif_tot = r << HSSCR_TOT_SHIFT;
@@ -1229,11 +1237,11 @@ static void sci_dma_tx_complete(void *arg)
 		schedule_work(&s->work_tx);
 	} else {
 		s->cookie_tx = -EINVAL;
-		if (port->type == PORT_SCIFA || port->type == PORT_SCIFB ||
-		    s->cfg->regtype == SCIx_RZ_SCIFA_REGTYPE) {
+		if (s->type == PORT_SCIFA || s->type == PORT_SCIFB ||
+		    s->regtype == SCIx_RZ_SCIFA_REGTYPE) {
 			u16 ctrl = sci_serial_in(port, SCSCR);
 			sci_serial_out(port, SCSCR, ctrl & ~SCSCR_TIE);
-			if (s->cfg->regtype == SCIx_RZ_SCIFA_REGTYPE) {
+			if (s->regtype == SCIx_RZ_SCIFA_REGTYPE) {
 				/* Switch irq from DMA to SCIF */
 				dmaengine_pause(s->chan_tx_saved);
 				enable_irq(s->irqs[SCIx_TXI_IRQ]);
@@ -1315,10 +1323,10 @@ static void sci_dma_rx_reenable_irq(struct sci_port *s)
 
 	/* Direct new serial port interrupts back to CPU */
 	scr = sci_serial_in(port, SCSCR);
-	if (port->type == PORT_SCIFA || port->type == PORT_SCIFB ||
-	    s->cfg->regtype == SCIx_RZ_SCIFA_REGTYPE) {
+	if (s->type == PORT_SCIFA || s->type == PORT_SCIFB ||
+	    s->regtype == SCIx_RZ_SCIFA_REGTYPE) {
 		enable_irq(s->irqs[SCIx_RXI_IRQ]);
-		if (s->cfg->regtype == SCIx_RZ_SCIFA_REGTYPE)
+		if (s->regtype == SCIx_RZ_SCIFA_REGTYPE)
 			s->ops->set_rtrg(port, s->rx_trigger);
 		else
 			scr &= ~SCSCR_RDRQE;
@@ -1558,8 +1566,8 @@ static enum hrtimer_restart sci_dma_rx_timer_fn(struct hrtimer *t)
 			tty_flip_buffer_push(&port->state->port);
 	}
 
-	if (port->type == PORT_SCIFA || port->type == PORT_SCIFB ||
-	    s->cfg->regtype == SCIx_RZ_SCIFA_REGTYPE)
+	if (s->type == PORT_SCIFA || s->type == PORT_SCIFB ||
+	    s->regtype == SCIx_RZ_SCIFA_REGTYPE)
 		sci_dma_rx_submit(s, true);
 
 	sci_dma_rx_reenable_irq(s);
@@ -1682,8 +1690,8 @@ static void sci_request_dma(struct uart_port *port)
 
 		s->chan_rx_saved = s->chan_rx = chan;
 
-		if (port->type == PORT_SCIFA || port->type == PORT_SCIFB ||
-		    s->cfg->regtype == SCIx_RZ_SCIFA_REGTYPE)
+		if (s->type == PORT_SCIFA || s->type == PORT_SCIFB ||
+		    s->regtype == SCIx_RZ_SCIFA_REGTYPE)
 			sci_dma_rx_submit(s, false);
 	}
 }
@@ -1753,10 +1761,10 @@ static irqreturn_t sci_rx_interrupt(int irq, void *ptr)
 		u16 ssr = sci_serial_in(port, SCxSR);
 
 		/* Disable future Rx interrupts */
-		if (port->type == PORT_SCIFA || port->type == PORT_SCIFB ||
-		    s->cfg->regtype == SCIx_RZ_SCIFA_REGTYPE) {
+		if (s->type == PORT_SCIFA || s->type == PORT_SCIFB ||
+		    s->regtype == SCIx_RZ_SCIFA_REGTYPE) {
 			disable_irq_nosync(s->irqs[SCIx_RXI_IRQ]);
-			if (s->cfg->regtype == SCIx_RZ_SCIFA_REGTYPE) {
+			if (s->regtype == SCIx_RZ_SCIFA_REGTYPE) {
 				s->ops->set_rtrg(port, 1);
 				scr |= SCSCR_RIE;
 			} else {
@@ -1820,7 +1828,7 @@ static irqreturn_t sci_tx_end_interrupt(int irq, void *ptr)
 	unsigned long flags;
 	u32 ctrl;
 
-	if (port->type != PORT_SCI)
+	if (s->type != PORT_SCI)
 		return sci_tx_interrupt(irq, ptr);
 
 	uart_port_lock_irqsave(port, &flags);
@@ -1867,7 +1875,7 @@ static irqreturn_t sci_er_interrupt(int irq, void *ptr)
 	}
 
 	/* Handle errors */
-	if (port->type == PORT_SCI) {
+	if (s->type == PORT_SCI) {
 		if (sci_handle_errors(port)) {
 			/* discard character in rx buffer */
 			sci_serial_in(port, SCxSR);
@@ -2091,7 +2099,9 @@ static unsigned int sci_tx_empty(struct uart_port *port)
 
 static void sci_set_rts(struct uart_port *port, bool state)
 {
-	if (port->type == PORT_SCIFA || port->type == PORT_SCIFB) {
+	struct sci_port *s = to_sci_port(port);
+
+	if (s->type == PORT_SCIFA || s->type == PORT_SCIFB) {
 		u16 data = sci_serial_in(port, SCPDR);
 
 		/* Active low */
@@ -2118,7 +2128,9 @@ static void sci_set_rts(struct uart_port *port, bool state)
 
 static bool sci_get_cts(struct uart_port *port)
 {
-	if (port->type == PORT_SCIFA || port->type == PORT_SCIFB) {
+	struct sci_port *s = to_sci_port(port);
+
+	if (s->type == PORT_SCIFA || s->type == PORT_SCIFB) {
 		/* Active low */
 		return !(sci_serial_in(port, SCPDR) & SCPDR_CTSD);
 	} else if (sci_getreg(port, SCSPTR)->size) {
@@ -2164,21 +2176,21 @@ static void sci_set_mctrl(struct uart_port *port, unsigned int mctrl)
 
 	if (!(mctrl & TIOCM_RTS)) {
 		/* Disable Auto RTS */
-		if (s->cfg->regtype != SCIx_RZV2H_SCIF_REGTYPE)
+		if (s->regtype != SCIx_RZV2H_SCIF_REGTYPE)
 			sci_serial_out(port, SCFCR,
 				       sci_serial_in(port, SCFCR) & ~SCFCR_MCE);
 
 		/* Clear RTS */
 		sci_set_rts(port, 0);
 	} else if (s->autorts) {
-		if (port->type == PORT_SCIFA || port->type == PORT_SCIFB) {
+		if (s->type == PORT_SCIFA || s->type == PORT_SCIFB) {
 			/* Enable RTS# pin function */
 			sci_serial_out(port, SCPCR,
 				sci_serial_in(port, SCPCR) & ~SCPCR_RTSC);
 		}
 
 		/* Enable Auto RTS */
-		if (s->cfg->regtype != SCIx_RZV2H_SCIF_REGTYPE)
+		if (s->regtype != SCIx_RZV2H_SCIF_REGTYPE)
 			sci_serial_out(port, SCFCR,
 				       sci_serial_in(port, SCFCR) | SCFCR_MCE);
 	} else {
@@ -2315,7 +2327,7 @@ static int sci_sck_calc(struct sci_port *s, unsigned int bps,
 	int err, min_err = INT_MAX;
 	unsigned int sr;
 
-	if (s->port.type != PORT_HSCIF)
+	if (s->type != PORT_HSCIF)
 		freq *= 2;
 
 	for_each_sr(sr, s) {
@@ -2342,7 +2354,7 @@ static int sci_brg_calc(struct sci_port *s, unsigned int bps,
 	int err, min_err = INT_MAX;
 	unsigned int sr, dl;
 
-	if (s->port.type != PORT_HSCIF)
+	if (s->type != PORT_HSCIF)
 		freq *= 2;
 
 	for_each_sr(sr, s) {
@@ -2375,7 +2387,7 @@ static int sci_scbrr_calc(struct sci_port *s, unsigned int bps,
 	unsigned int sr, br, prediv, scrate, c;
 	int err, min_err = INT_MAX;
 
-	if (s->port.type != PORT_HSCIF)
+	if (s->type != PORT_HSCIF)
 		freq *= 2;
 
 	/*
@@ -2460,8 +2472,8 @@ static void sci_reset(struct uart_port *port)
 			s->ops->set_rtrg(port, 1);
 			timer_setup(&s->rx_fifo_timer, rx_fifo_timer_fn, 0);
 		} else {
-			if (port->type == PORT_SCIFA ||
-			    port->type == PORT_SCIFB)
+			if (s->type == PORT_SCIFA ||
+			    s->type == PORT_SCIFB)
 				s->ops->set_rtrg(port, 1);
 			else
 				s->ops->set_rtrg(port, s->rx_trigger);
@@ -2521,8 +2533,8 @@ static void sci_set_termios(struct uart_port *port, struct ktermios *termios,
 	 */
 
 	/* Optional Undivided External Clock */
-	if (s->clk_rates[SCI_SCK] && port->type != PORT_SCIFA &&
-	    port->type != PORT_SCIFB) {
+	if (s->clk_rates[SCI_SCK] && s->type != PORT_SCIFA &&
+	    s->type != PORT_SCIFB) {
 		err = sci_sck_calc(s, baud, &srr1);
 		if (abs(err) < abs(min_err)) {
 			best_clk = SCI_SCK;
@@ -2607,7 +2619,7 @@ static void sci_set_termios(struct uart_port *port, struct ktermios *termios,
 		sci_serial_out(port, SEMR, 0);
 
 	if (best_clk >= 0) {
-		if (port->type == PORT_SCIFA || port->type == PORT_SCIFB)
+		if (s->type == PORT_SCIFA || s->type == PORT_SCIFB)
 			switch (srr + 1) {
 			case 5:  smr_val |= SCSMR_SRC_5;  break;
 			case 7:  smr_val |= SCSMR_SRC_7;  break;
@@ -2692,12 +2704,12 @@ static void sci_set_termios(struct uart_port *port, struct ktermios *termios,
 	 * (transmit interrupt enable) or in the same instruction to
 	 * start the transmitting process. So skip setting TE here for SCI.
 	 */
-	if (port->type != PORT_SCI)
+	if (s->type != PORT_SCI)
 		scr_val |= SCSCR_TE;
 	scr_val |= SCSCR_RE | (s->cfg->scscr & ~(SCSCR_CKE1 | SCSCR_CKE0));
 	sci_serial_out(port, SCSCR, scr_val | s->hscif_tot);
 	if ((srr + 1 == 5) &&
-	    (port->type == PORT_SCIFA || port->type == PORT_SCIFB)) {
+	    (s->type == PORT_SCIFA || s->type == PORT_SCIFB)) {
 		/*
 		 * In asynchronous mode, when the sampling rate is 1/5, first
 		 * received data may become invalid on some SCIFA and SCIFB.
@@ -2741,7 +2753,9 @@ void sci_pm(struct uart_port *port, unsigned int state,
 
 static const char *sci_type(struct uart_port *port)
 {
-	switch (port->type) {
+	struct sci_port *s = to_sci_port(port);
+
+	switch (s->type) {
 	case PORT_IRDA:
 		return "irda";
 	case PORT_SCI:
@@ -2825,8 +2839,7 @@ void sci_config_port(struct uart_port *port, int flags)
 {
 	if (flags & UART_CONFIG_TYPE) {
 		struct sci_port *sport = to_sci_port(port);
-
-		port->type = sport->cfg->type;
+		port->type = SCI_PUBLIC_PORT_ID(sport->type);
 		sci_request_port(port);
 	}
 }
@@ -2964,7 +2977,7 @@ static int sci_init_clocks(struct sci_port *sci_port, struct device *dev)
 	struct clk *clk;
 	unsigned int i;
 
-	if (sci_port->cfg->type == PORT_HSCIF)
+	if (sci_port->type == PORT_HSCIF)
 		clk_names[SCI_SCK] = "hsck";
 
 	for (i = 0; i < SCI_NUM_CLKS; i++) {
@@ -3050,6 +3063,9 @@ static int sci_init_single(struct platform_device *dev,
 
 	sci_port->cfg	= p;
 
+	sci_port->type	= p->type;
+	sci_port->regtype = p->regtype;
+
 	port->iotype	= UPIO_MEM;
 	port->line	= index;
 	port->has_sysrq = IS_ENABLED(CONFIG_SERIAL_SH_SCI_CONSOLE);
@@ -3128,11 +3144,11 @@ static int sci_init_single(struct platform_device *dev,
 			return ret;
 	}
 
-	port->type		= p->type;
+	port->type		= SCI_PUBLIC_PORT_ID(p->type);
 	port->flags		= UPF_FIXED_PORT | UPF_BOOT_AUTOCONF | p->flags;
 	port->fifosize		= sci_port->params->fifosize;
 
-	if (port->type == PORT_SCI && !dev->dev.of_node) {
+	if (p->type == PORT_SCI && !dev->dev.of_node) {
 		if (sci_port->reg_size >= 0x20)
 			port->regshift = 2;
 		else
@@ -3322,13 +3338,13 @@ static struct uart_driver sci_uart_driver = {
 
 static void sci_remove(struct platform_device *dev)
 {
-	struct sci_port *port = platform_get_drvdata(dev);
-	unsigned int type = port->port.type;	/* uart_remove_... clears it */
+	struct sci_port *s = platform_get_drvdata(dev);
+	unsigned int type = s->type;	/* uart_remove_... clears it */
 
-	sci_ports_in_use &= ~BIT(port->port.line);
-	uart_remove_one_port(&sci_uart_driver, &port->port);
+	sci_ports_in_use &= ~BIT(s->port.line);
+	uart_remove_one_port(&sci_uart_driver, &s->port);
 
-	if (port->port.fifosize > 1)
+	if (s->port.fifosize > 1)
 		device_remove_file(&dev->dev, &dev_attr_rx_fifo_trigger);
 	if (type == PORT_SCIFA || type == PORT_SCIFB || type == PORT_HSCIF)
 		device_remove_file(&dev->dev, &dev_attr_rx_fifo_timeout);
@@ -3682,8 +3698,8 @@ static int sci_probe(struct platform_device *dev)
 		if (ret)
 			return ret;
 	}
-	if (sp->port.type == PORT_SCIFA || sp->port.type == PORT_SCIFB ||
-	    sp->port.type == PORT_HSCIF) {
+	if (sp->type == PORT_SCIFA || sp->type == PORT_SCIFB ||
+	    sp->type == PORT_HSCIF) {
 		ret = device_create_file(&dev->dev, &dev_attr_rx_fifo_timeout);
 		if (ret) {
 			if (sp->port.fifosize > 1) {
@@ -3799,8 +3815,11 @@ int __init scix_early_console_setup(struct earlycon_device *device,
 	if (!device->port.membase)
 		return -ENODEV;
 
-	device->port.type = data->type;
+	device->port.type = SCI_PUBLIC_PORT_ID(data->type);
+
 	sci_ports[0].port = device->port;
+	sci_ports[0].type = data->type;
+	sci_ports[0].regtype = data->regtype;
 
 	port_cfg.type = data->type;
 	port_cfg.regtype = data->regtype;
-- 
2.43.0

[PATCH v10 07/10] serial: sh-sci: Add support for RZ/T2H SCI

[Thierry Bultel]

Define a new RSCI port type, and the RSCI 32 bits registers set.
The RZ/T2H SCI has a a fifo, and a quite different set of registers
from the original SH SCI ones.
DMA is not supported yet.

Reviewed-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Thierry Bultel <thierry.bultel.yh@bp.renesas.com>
---
Changes v9->v10:
  - removed unneed #ifdef in rsci.h
  - use same error message in sci_init_clocks
Changes v8->v9:
  - Fixed some code formatting
  - Renamed rzt2_sci_uart_ops to rsci_uart_ops
  - Renamed of_sci_r9a09g077_data to of_sci_rsci_data
  - Added EXPORT_SYMBOL for public functions
  - Added MODULE_LICENSE & MODULE_DESCRIPTION
  - Fixed RSCI clock names
  - Fixed SCI_PORT_RSCI using BIT(7)
Changes v7->v8:
  - s/rzsci/rsci/g
  - declared SCI_PORT_RSCI as private port ID
  - look for secondary clock
  - report error when rsci clocks are not found
Changes v6->v7:
  - Renamed compatible string to r9a09g077-rsci
Changes v5->v6:
  - Rename SERIAL_RZ_SCI_T2 to CONFIG_SERIAL_RSCI
  - Rename rz-sci-t2.{c,h} to rsci.{c,h}
  - Rename port type to PORT_RSCI
  - Rename sci_r9a09g077_data to of_sci_r9a09g077_data for consistency
Changes v4->v5:
  - Rename SERIAL_RZ_SCI to SERIAL_RZ_SCI_T2
  - Rename rzsci.{c,h} to rz-sci-t2.{c,h}
  - Rename port type to PORT_RZ_SCI_T2
  - Set sci_shutdown ops pointer (needed by systemd for having a console)
Changes v3->v4:
  - Added missing #include <bitfield.h>
  - Fix christmas tree code style in rzsci_transmit_chars.
---
 drivers/tty/serial/Kconfig         |   7 +
 drivers/tty/serial/Makefile        |   1 +
 drivers/tty/serial/rsci.c          | 468 +++++++++++++++++++++++++++++
 drivers/tty/serial/rsci.h          |  10 +
 drivers/tty/serial/sh-sci-common.h |   5 +
 drivers/tty/serial/sh-sci.c        |  53 +++-
 6 files changed, 534 insertions(+), 10 deletions(-)
 create mode 100644 drivers/tty/serial/rsci.c
 create mode 100644 drivers/tty/serial/rsci.h

diff --git a/drivers/tty/serial/Kconfig b/drivers/tty/serial/Kconfig
index 79a8186d3361..44427415a80d 100644
--- a/drivers/tty/serial/Kconfig
+++ b/drivers/tty/serial/Kconfig
@@ -675,6 +675,13 @@ config SERIAL_SH_SCI_DMA
 	depends on SERIAL_SH_SCI && DMA_ENGINE
 	default ARCH_RENESAS
 
+config SERIAL_RSCI
+	tristate "Support for Renesas RZ/T2H SCI variant"
+	depends on SERIAL_SH_SCI
+	help
+	  Support for the RZ/T2H SCI variant with fifo.
+	  Say Y if you want to be able to use the RZ/T2H SCI serial port.
+
 config SERIAL_HS_LPC32XX
 	tristate "LPC32XX high speed serial port support"
 	depends on ARCH_LPC32XX || COMPILE_TEST
diff --git a/drivers/tty/serial/Makefile b/drivers/tty/serial/Makefile
index d58d9f719889..a2ccbc508ec5 100644
--- a/drivers/tty/serial/Makefile
+++ b/drivers/tty/serial/Makefile
@@ -71,6 +71,7 @@ obj-$(CONFIG_SERIAL_QCOM_GENI)		+= qcom_geni_serial.o
 obj-$(CONFIG_SERIAL_QE)			+= ucc_uart.o
 obj-$(CONFIG_SERIAL_RDA)		+= rda-uart.o
 obj-$(CONFIG_SERIAL_RP2)		+= rp2.o
+obj-$(CONFIG_SERIAL_RSCI)		+= rsci.o
 obj-$(CONFIG_SERIAL_SA1100)		+= sa1100.o
 obj-$(CONFIG_SERIAL_SAMSUNG)		+= samsung_tty.o
 obj-$(CONFIG_SERIAL_SB1250_DUART)	+= sb1250-duart.o
diff --git a/drivers/tty/serial/rsci.c b/drivers/tty/serial/rsci.c
new file mode 100644
index 000000000000..4410f9eca7b9
--- /dev/null
+++ b/drivers/tty/serial/rsci.c
@@ -0,0 +1,468 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2025 Renesas Electronics Corp.
+ */
+
+#include <linux/bitfield.h>
+#include <linux/bitops.h>
+#include <linux/io.h>
+#include <linux/iopoll.h>
+#include <linux/serial_core.h>
+#include <linux/serial_sci.h>
+#include <linux/tty_flip.h>
+#include "rsci.h"
+
+/* RSCI registers */
+#define RDR	0x00
+#define TDR	0x04
+#define CCR0	0x08
+#define CCR1	0x0C
+#define CCR2	0x10
+#define CCR3	0x14
+#define CCR4	0x18
+#define FCR	0x24
+#define DCR	0x30
+#define CSR	0x48
+#define FRSR	0x50
+#define FTSR	0x54
+#define CFCLR	0x68
+#define FFCLR	0x70
+
+/* RDR (Receive Data Register) */
+#define RDR_FFER		BIT(12) /* FIFO Framing Error */
+#define RDR_FPER		BIT(11) /* FIFO Parity Error */
+#define RDR_RDAT_MSK		GENMASK(8, 0)
+
+/* TDR (Transmit Data Register) */
+#define TDR_MPBT		BIT(9)	/* Multiprocessor Transfer */
+#define TDR_TDAT_9BIT_LSHIFT	0
+#define TDR_TDAT_9BIT_VAL	0x1FF
+#define TDR_TDAT_9BIT_MSK	(TDR_TDAT_9BIT_VAL << TDR_TDAT_9BIT_LSHIFT)
+
+/* CCR0 (Common Control Register 0) */
+#define CCR0_SSE		BIT(24)	/* SSn# Pin Function Enable */
+#define CCR0_TEIE		BIT(21)	/* Transmit End Interrupt Enable */
+#define CCR0_TIE		BIT(20)	/* Transmit Interrupt Enable */
+#define CCR0_RIE		BIT(16)	/* Receive Interrupt Enable */
+#define CCR0_IDSEL		BIT(10)	/* ID Frame Select */
+#define CCR0_DCME		BIT(9)	/* Data Compare Match Enable */
+#define CCR0_MPIE		BIT(8)	/* Multiprocessor Interrupt Enable */
+#define CCR0_TE			BIT(4)	/* Transmit Enable */
+#define CCR0_RE			BIT(0)	/* Receive Enable */
+
+/* CCR1 (Common Control Register 1) */
+#define CCR1_NFEN		BIT(28)	/* Digital Noise Filter Function */
+#define CCR1_SHARPS		BIT(20)	/* Half -duplex Communication Select */
+#define CCR1_SPLP		BIT(16)	/* Loopback Control */
+#define CCR1_RINV		BIT(13)	/* RxD invert */
+#define CCR1_TINV		BIT(12)	/* TxD invert */
+#define CCR1_PM			BIT(9)	/* Parity Mode */
+#define CCR1_PE			BIT(8)	/* Parity Enable */
+#define CCR1_SPB2IO		BIT(5)	/* Serial Port Break I/O */
+#define CCR1_SPB2DT		BIT(4)	/* Serial Port Break Data Select */
+#define CCR1_CTSPEN		BIT(1)	/* CTS External Pin Enable */
+#define CCR1_CTSE		BIT(0)	/* CTS Enable */
+
+/* FCR (FIFO Control Register) */
+#define FCR_RFRST		BIT(23)	/* Receive FIFO Data Register Reset */
+#define FCR_TFRST		BIT(15)	/* Transmit FIFO Data Register Reset */
+#define FCR_DRES		BIT(0)	/* Incoming Data Ready Error Select */
+#define FCR_RTRG4_0		GENMASK(20, 16)
+#define FCR_TTRG		GENMASK(12, 8)
+
+/* CSR (Common Status Register) */
+#define CSR_RDRF		BIT(31)	/* Receive Data Full */
+#define CSR_TEND		BIT(30)	/* Transmit End Flag */
+#define CSR_TDRE		BIT(29)	/* Transmit Data Empty */
+#define CSR_FER			BIT(28)	/* Framing Error */
+#define CSR_PER			BIT(27)	/* Parity Error */
+#define CSR_MFF			BIT(26)	/* Mode Fault Error */
+#define CSR_ORER		BIT(24)	/* Overrun Error */
+#define CSR_DFER		BIT(18)	/* Data Compare Match Framing Error */
+#define CSR_DPER		BIT(17)	/* Data Compare Match Parity Error */
+#define CSR_DCMF		BIT(16)	/* Data Compare Match */
+#define CSR_RXDMON		BIT(15)	/* Serial Input Data Monitor */
+#define CSR_ERS			BIT(4)	/* Error Signal Status */
+
+#define SCxSR_ERRORS(port)	(to_sci_port(port)->params->error_mask)
+#define SCxSR_ERROR_CLEAR(port)	(to_sci_port(port)->params->error_clear)
+
+#define RSCI_DEFAULT_ERROR_MASK	(CSR_PER | CSR_FER)
+
+#define RSCI_RDxF_CLEAR		(CFCLR_RDRFC)
+#define RSCI_ERROR_CLEAR	(CFCLR_PERC | CFCLR_FERC)
+#define RSCI_TDxE_CLEAR		(CFCLR_TDREC)
+#define RSCI_BREAK_CLEAR	(CFCLR_PERC | CFCLR_FERC | CFCLR_ORERC)
+
+/* FRSR (FIFO Receive Status Register) */
+#define FRSR_R5_0		GENMASK(13, 8)	/* Receive FIFO Data Count */
+#define FRSR_DR			BIT(0)	/* Receive Data Ready */
+
+/* CFCLR (Common Flag CLear Register) */
+#define CFCLR_RDRFC		BIT(31)	/* RDRF Clear */
+#define CFCLR_TDREC		BIT(29)	/* TDRE Clear */
+#define CFCLR_FERC		BIT(28)	/* FER Clear */
+#define CFCLR_PERC		BIT(27)	/* PER Clear */
+#define CFCLR_MFFC		BIT(26)	/* MFF Clear */
+#define CFCLR_ORERC		BIT(24)	/* ORER Clear */
+#define CFCLR_DFERC		BIT(18)	/* DFER Clear */
+#define CFCLR_DPERC		BIT(17)	/* DPER Clear */
+#define CFCLR_DCMFC		BIT(16)	/* DCMF Clear */
+#define CFCLR_ERSC		BIT(4)	/* ERS Clear */
+#define CFCLR_CLRFLAG		(CFCLR_RDRFC | CFCLR_FERC | CFCLR_PERC | \
+				 CFCLR_MFFC | CFCLR_ORERC | CFCLR_DFERC | \
+				 CFCLR_DPERC | CFCLR_DCMFC | CFCLR_ERSC)
+
+/* FFCLR (FIFO Flag CLear Register) */
+#define FFCLR_DRC		BIT(0)	/* DR Clear */
+
+#define DCR_DEPOL		BIT(0)
+
+static u32 rsci_serial_in(struct uart_port *p, int offset)
+{
+	return readl(p->membase + offset);
+}
+
+static void rsci_serial_out(struct uart_port *p, int offset, int value)
+{
+	writel(value, p->membase + offset);
+}
+
+static void rsci_clear_DRxC(struct uart_port *port)
+{
+	rsci_serial_out(port, CFCLR, CFCLR_RDRFC);
+	rsci_serial_out(port, FFCLR, FFCLR_DRC);
+}
+
+static void rsci_clear_SCxSR(struct uart_port *port, unsigned int mask)
+{
+	rsci_serial_out(port, CFCLR, mask);
+}
+
+static void rsci_start_rx(struct uart_port *port)
+{
+	unsigned int ctrl;
+
+	ctrl = rsci_serial_in(port, CCR0);
+	ctrl |= CCR0_RIE;
+	rsci_serial_out(port, CCR0, ctrl);
+}
+
+static void rsci_set_termios(struct uart_port *port, struct ktermios *termios,
+			      const struct ktermios *old)
+{
+	struct sci_port *s = to_sci_port(port);
+	unsigned long flags;
+
+	sci_port_enable(s);
+	uart_port_lock_irqsave(port, &flags);
+
+	/* For now, only RX enabling is supported */
+	if (termios->c_cflag & CREAD)
+		rsci_start_rx(port);
+
+	uart_port_unlock_irqrestore(port, flags);
+	sci_port_disable(s);
+}
+
+static int rsci_txfill(struct uart_port *port)
+{
+	return rsci_serial_in(port, FTSR);
+}
+
+static int rsci_rxfill(struct uart_port *port)
+{
+	u32 val = rsci_serial_in(port, FRSR);
+
+	return FIELD_GET(FRSR_R5_0, val);
+}
+
+static unsigned int rsci_tx_empty(struct uart_port *port)
+{
+	unsigned int status = rsci_serial_in(port, CSR);
+	unsigned int in_tx_fifo = rsci_txfill(port);
+
+	return (status & CSR_TEND) && !in_tx_fifo ? TIOCSER_TEMT : 0;
+}
+
+static void rsci_set_mctrl(struct uart_port *port, unsigned int mctrl)
+{
+	/* Not supported yet */
+}
+
+static unsigned int rsci_get_mctrl(struct uart_port *port)
+{
+	/* Not supported yet */
+	return 0;
+}
+
+static void rsci_clear_CFC(struct uart_port *port, unsigned int mask)
+{
+	rsci_serial_out(port, CFCLR, mask);
+}
+
+static void rsci_start_tx(struct uart_port *port)
+{
+	struct sci_port *sp = to_sci_port(port);
+	u32 ctrl;
+
+	if (sp->chan_tx)
+		return;
+
+	/*
+	 * TE (Transmit Enable) must be set after setting TIE
+	 * (Transmit Interrupt Enable) or in the same instruction
+	 * to start the transmit process.
+	 */
+	ctrl = rsci_serial_in(port, CCR0);
+	ctrl |= CCR0_TIE | CCR0_TE;
+	rsci_serial_out(port, CCR0, ctrl);
+}
+
+static void rsci_stop_tx(struct uart_port *port)
+{
+	u32 ctrl;
+
+	ctrl = rsci_serial_in(port, CCR0);
+	ctrl &= ~CCR0_TIE;
+	rsci_serial_out(port, CCR0, ctrl);
+}
+
+static void rsci_stop_rx(struct uart_port *port)
+{
+	u32 ctrl;
+
+	ctrl = rsci_serial_in(port, CCR0);
+	ctrl &= ~CCR0_RIE;
+	rsci_serial_out(port, CCR0, ctrl);
+}
+
+static int rsci_txroom(struct uart_port *port)
+{
+	return port->fifosize - rsci_txfill(port);
+}
+
+static void rsci_transmit_chars(struct uart_port *port)
+{
+	unsigned int stopped = uart_tx_stopped(port);
+	struct tty_port *tport = &port->state->port;
+	u32 status, ctrl;
+	int count;
+
+	status = rsci_serial_in(port, CSR);
+	if (!(status & CSR_TDRE)) {
+		ctrl = rsci_serial_in(port, CCR0);
+		if (kfifo_is_empty(&tport->xmit_fifo))
+			ctrl &= ~CCR0_TIE;
+		else
+			ctrl |= CCR0_TIE;
+		rsci_serial_out(port, CCR0, ctrl);
+		return;
+	}
+
+	count = rsci_txroom(port);
+
+	do {
+		unsigned char c;
+
+		if (port->x_char) {
+			c = port->x_char;
+			port->x_char = 0;
+		} else if (stopped || !kfifo_get(&tport->xmit_fifo, &c)) {
+			break;
+		}
+
+		rsci_clear_CFC(port, CFCLR_TDREC);
+		rsci_serial_out(port, TDR, c);
+
+		port->icount.tx++;
+	} while (--count > 0);
+
+	if (kfifo_len(&tport->xmit_fifo) < WAKEUP_CHARS)
+		uart_write_wakeup(port);
+
+	if (kfifo_is_empty(&tport->xmit_fifo)) {
+		ctrl = rsci_serial_in(port, CCR0);
+		ctrl &= ~CCR0_TIE;
+		ctrl |= CCR0_TEIE;
+		rsci_serial_out(port, CCR0, ctrl);
+	}
+}
+
+static void rsci_receive_chars(struct uart_port *port)
+{
+	struct tty_port *tport = &port->state->port;
+	u32 rdat, status, frsr_status = 0;
+	int i, count, copied = 0;
+	unsigned char flag;
+
+	status = rsci_serial_in(port, CSR);
+	frsr_status = rsci_serial_in(port, FRSR);
+
+	if (!(status & CSR_RDRF) && !(frsr_status & FRSR_DR))
+		return;
+
+	while (1) {
+		/* Don't copy more bytes than there is room for in the buffer */
+		count = tty_buffer_request_room(tport, rsci_rxfill(port));
+
+		/* If for any reason we can't copy more data, we're done! */
+		if (count == 0)
+			break;
+
+		for (i = 0; i < count; i++) {
+			char c;
+
+			rdat = rsci_serial_in(port, RDR);
+			/* 9-bits data is not supported yet */
+			c = rdat & RDR_RDAT_MSK;
+
+			if (uart_handle_sysrq_char(port, c)) {
+				count--;
+				i--;
+				continue;
+			}
+
+			/* Store data and status.
+			 * Non FIFO mode is not supported
+			 */
+			if (rdat & RDR_FFER) {
+				flag = TTY_FRAME;
+				port->icount.frame++;
+			} else if (rdat & RDR_FPER) {
+				flag = TTY_PARITY;
+				port->icount.parity++;
+			} else {
+				flag = TTY_NORMAL;
+			}
+
+			tty_insert_flip_char(tport, c, flag);
+		}
+
+		rsci_serial_in(port, CSR); /* dummy read */
+		rsci_clear_DRxC(port);
+
+		copied += count;
+		port->icount.rx += count;
+	}
+
+	if (copied) {
+		/* Tell the rest of the system the news. New characters! */
+		tty_flip_buffer_push(tport);
+	} else {
+		/* TTY buffers full; read from RX reg to prevent lockup */
+		rsci_serial_in(port, RDR);
+		rsci_serial_in(port, CSR); /* dummy read */
+		rsci_clear_DRxC(port);
+	}
+}
+
+static void rsci_poll_put_char(struct uart_port *port, unsigned char c)
+{
+	u32 status;
+	int ret;
+
+	ret = readl_relaxed_poll_timeout_atomic(port->membase + CSR, status,
+						(status & CSR_TDRE), 100,
+						USEC_PER_SEC);
+	if (ret != 0) {
+		dev_err(port->dev,
+			"Error while sending data in UART TX : %d\n", ret);
+		goto done;
+	}
+	rsci_serial_out(port, TDR, c);
+done:
+	rsci_clear_SCxSR(port, CFCLR_TDREC);
+}
+
+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;
+	rsci_serial_out(port, CCR0, ctrl_temp);
+}
+
+static const char *rsci_type(struct uart_port *port)
+{
+	return "rsci";
+}
+
+static size_t rsci_suspend_regs_size(void)
+{
+	return 0;
+}
+
+static const struct sci_common_regs rsci_common_regs = {
+	.status = CSR,
+	.control = CCR0,
+};
+
+static const struct sci_port_params_bits rsci_port_param_bits = {
+	.rxtx_enable = CCR0_RE | CCR0_TE,
+	.te_clear = CCR0_TE | CCR0_TEIE,
+	.poll_sent_bits = CSR_TDRE | CSR_TEND,
+};
+
+static const struct sci_port_params rsci_port_params = {
+	.fifosize = 16,
+	.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 uart_ops rsci_uart_ops = {
+	.tx_empty	= rsci_tx_empty,
+	.set_mctrl	= rsci_set_mctrl,
+	.get_mctrl	= rsci_get_mctrl,
+	.start_tx	= rsci_start_tx,
+	.stop_tx	= rsci_stop_tx,
+	.stop_rx	= rsci_stop_rx,
+	.startup	= sci_startup,
+	.shutdown	= sci_shutdown,
+	.set_termios	= rsci_set_termios,
+	.pm		= sci_pm,
+	.type		= rsci_type,
+	.release_port	= sci_release_port,
+	.request_port	= sci_request_port,
+	.config_port	= sci_config_port,
+	.verify_port	= sci_verify_port,
+};
+
+static const struct sci_port_ops rsci_port_ops = {
+	.read_reg		= rsci_serial_in,
+	.write_reg		= rsci_serial_out,
+	.clear_SCxSR		= rsci_clear_SCxSR,
+	.transmit_chars		= rsci_transmit_chars,
+	.receive_chars		= rsci_receive_chars,
+	.poll_put_char		= rsci_poll_put_char,
+	.prepare_console_write	= rsci_prepare_console_write,
+	.suspend_regs_size	= rsci_suspend_regs_size,
+};
+
+struct sci_of_data of_sci_rsci_data = {
+	.type = SCI_PORT_RSCI,
+	.ops = &rsci_port_ops,
+	.uart_ops = &rsci_uart_ops,
+	.params = &rsci_port_params,
+};
+
+#ifdef CONFIG_SERIAL_SH_SCI_EARLYCON
+
+static int __init rsci_early_console_setup(struct earlycon_device *device,
+					       const char *opt)
+{
+	return scix_early_console_setup(device, &of_sci_rsci_data);
+}
+
+OF_EARLYCON_DECLARE(rsci, "renesas,r9a09g077-rsci", rsci_early_console_setup);
+
+#endif /* CONFIG_SERIAL_SH_SCI_EARLYCON */
+
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("RSCI serial driver");
diff --git a/drivers/tty/serial/rsci.h b/drivers/tty/serial/rsci.h
new file mode 100644
index 000000000000..2af3f28b465a
--- /dev/null
+++ b/drivers/tty/serial/rsci.h
@@ -0,0 +1,10 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+
+#ifndef __RSCI_H__
+#define __RSCI_H__
+
+#include "sh-sci-common.h"
+
+extern struct sci_of_data of_sci_rsci_data;
+
+#endif /* __RSCI_H__ */
diff --git a/drivers/tty/serial/sh-sci-common.h b/drivers/tty/serial/sh-sci-common.h
index fcddf66780c9..e3c028df14f1 100644
--- a/drivers/tty/serial/sh-sci-common.h
+++ b/drivers/tty/serial/sh-sci-common.h
@@ -5,6 +5,11 @@
 
 #include <linux/serial_core.h>
 
+/* Private port IDs */
+enum SCI_PORT_TYPE {
+	SCI_PORT_RSCI = BIT(7) | 0,
+};
+
 enum SCI_CLKS {
 	SCI_FCK,		/* Functional Clock */
 	SCI_SCK,		/* Optional External Clock */
diff --git a/drivers/tty/serial/sh-sci.c b/drivers/tty/serial/sh-sci.c
index be719c0db64a..ec226b63e943 100644
--- a/drivers/tty/serial/sh-sci.c
+++ b/drivers/tty/serial/sh-sci.c
@@ -54,6 +54,7 @@
 #include <asm/platform_early.h>
 #endif
 
+#include "rsci.h"
 #include "serial_mctrl_gpio.h"
 #include "sh-sci.h"
 #include "sh-sci-common.h"
@@ -550,6 +551,7 @@ void sci_port_enable(struct sci_port *sci_port)
 	}
 	sci_port->port.uartclk = sci_port->clk_rates[SCI_FCK];
 }
+EXPORT_SYMBOL(sci_port_enable);
 
 void sci_port_disable(struct sci_port *sci_port)
 {
@@ -563,6 +565,7 @@ void sci_port_disable(struct sci_port *sci_port)
 
 	pm_runtime_put_sync(sci_port->port.dev);
 }
+EXPORT_SYMBOL(sci_port_disable);
 
 static inline unsigned long port_rx_irq_mask(struct uart_port *port)
 {
@@ -1828,7 +1831,7 @@ static irqreturn_t sci_tx_end_interrupt(int irq, void *ptr)
 	unsigned long flags;
 	u32 ctrl;
 
-	if (s->type != PORT_SCI)
+	if (s->type != PORT_SCI && s->type != SCI_PORT_RSCI)
 		return sci_tx_interrupt(irq, ptr);
 
 	uart_port_lock_irqsave(port, &flags);
@@ -2289,6 +2292,7 @@ int sci_startup(struct uart_port *port)
 
 	return 0;
 }
+EXPORT_SYMBOL(sci_startup);
 
 void sci_shutdown(struct uart_port *port)
 {
@@ -2319,6 +2323,7 @@ void sci_shutdown(struct uart_port *port)
 	sci_free_irq(s);
 	sci_free_dma(port);
 }
+EXPORT_SYMBOL(sci_shutdown);
 
 static int sci_sck_calc(struct sci_port *s, unsigned int bps,
 			unsigned int *srr)
@@ -2750,6 +2755,7 @@ void sci_pm(struct uart_port *port, unsigned int state,
 		break;
 	}
 }
+EXPORT_SYMBOL(sci_pm);
 
 static const char *sci_type(struct uart_port *port)
 {
@@ -2812,6 +2818,7 @@ void sci_release_port(struct uart_port *port)
 
 	release_mem_region(port->mapbase, sport->reg_size);
 }
+EXPORT_SYMBOL(sci_release_port);
 
 int sci_request_port(struct uart_port *port)
 {
@@ -2834,6 +2841,7 @@ int sci_request_port(struct uart_port *port)
 
 	return 0;
 }
+EXPORT_SYMBOL(sci_request_port);
 
 void sci_config_port(struct uart_port *port, int flags)
 {
@@ -2843,6 +2851,7 @@ void sci_config_port(struct uart_port *port, int flags)
 		sci_request_port(port);
 	}
 }
+EXPORT_SYMBOL(sci_config_port);
 
 int sci_verify_port(struct uart_port *port, struct serial_struct *ser)
 {
@@ -2852,6 +2861,7 @@ int sci_verify_port(struct uart_port *port, struct serial_struct *ser)
 
 	return 0;
 }
+EXPORT_SYMBOL(sci_verify_port);
 
 static void sci_prepare_console_write(struct uart_port *port, u32 ctrl)
 {
@@ -2977,14 +2987,27 @@ static int sci_init_clocks(struct sci_port *sci_port, struct device *dev)
 	struct clk *clk;
 	unsigned int i;
 
-	if (sci_port->type == PORT_HSCIF)
+	if (sci_port->type == PORT_HSCIF) {
 		clk_names[SCI_SCK] = "hsck";
+	} else if (sci_port->type == SCI_PORT_RSCI) {
+		clk_names[SCI_FCK] = "operation";
+		clk_names[SCI_BRG_INT] = "bus";
+	}
 
 	for (i = 0; i < SCI_NUM_CLKS; i++) {
-		clk = devm_clk_get_optional(dev, clk_names[i]);
+		const char *name = clk_names[i];
+
+		clk = devm_clk_get_optional(dev, name);
 		if (IS_ERR(clk))
 			return PTR_ERR(clk);
 
+		if (!clk && sci_port->type == SCI_PORT_RSCI &&
+		    (i == SCI_FCK || i == SCI_BRG_INT)) {
+			return dev_err_probe(dev, -ENODEV,
+					     "failed to get %s\n",
+					     name);
+		}
+
 		if (!clk && i == SCI_FCK) {
 			/*
 			 * Not all SH platforms declare a clock lookup entry
@@ -2995,13 +3018,13 @@ static int sci_init_clocks(struct sci_port *sci_port, struct device *dev)
 			if (IS_ERR(clk))
 				return dev_err_probe(dev, PTR_ERR(clk),
 						     "failed to get %s\n",
-						     clk_names[i]);
+						     name);
 		}
 
 		if (!clk)
-			dev_dbg(dev, "failed to get %s\n", clk_names[i]);
+			dev_dbg(dev, "failed to get %s\n", name);
 		else
-			dev_dbg(dev, "clk %s is %pC rate %lu\n", clk_names[i],
+			dev_dbg(dev, "clk %s is %pC rate %lu\n", name,
 				clk, clk_get_rate(clk));
 		sci_port->clks[i] = clk;
 	}
@@ -3085,10 +3108,10 @@ static int sci_init_single(struct platform_device *dev,
 	}
 
 	/*
-	 * The fourth interrupt on SCI port is transmit end interrupt, so
+	 * The fourth interrupt on SCI and RSCI port is transmit end interrupt, so
 	 * shuffle the interrupts.
 	 */
-	if (p->type == PORT_SCI)
+	if (p->type == PORT_SCI || p->type == SCI_PORT_RSCI)
 		swap(sci_port->irqs[SCIx_BRI_IRQ], sci_port->irqs[SCIx_TEI_IRQ]);
 
 	/* The SCI generates several interrupts. They can be muxed together or
@@ -3122,6 +3145,9 @@ static int sci_init_single(struct platform_device *dev,
 		else
 			sci_port->rx_trigger = 8;
 		break;
+	case SCI_PORT_RSCI:
+		sci_port->rx_trigger = 15;
+		break;
 	default:
 		sci_port->rx_trigger = 1;
 		break;
@@ -3346,7 +3372,8 @@ static void sci_remove(struct platform_device *dev)
 
 	if (s->port.fifosize > 1)
 		device_remove_file(&dev->dev, &dev_attr_rx_fifo_trigger);
-	if (type == PORT_SCIFA || type == PORT_SCIFB || type == PORT_HSCIF)
+	if (type == PORT_SCIFA || type == PORT_SCIFB || type == PORT_HSCIF ||
+	    type == SCI_PORT_RSCI)
 		device_remove_file(&dev->dev, &dev_attr_rx_fifo_timeout);
 }
 
@@ -3440,6 +3467,12 @@ static const struct of_device_id of_sci_match[] __maybe_unused = {
 		.compatible = "renesas,scif-r9a09g057",
 		.data = &of_sci_scif_rzv2h,
 	},
+#ifdef CONFIG_SERIAL_RSCI
+	{
+		.compatible = "renesas,r9a09g077-rsci",
+		.data = &of_sci_rsci_data,
+	},
+#endif	/* CONFIG_SERIAL_RSCI */
 	/* Family-specific types */
 	{
 		.compatible = "renesas,rcar-gen1-scif",
@@ -3699,7 +3732,7 @@ static int sci_probe(struct platform_device *dev)
 			return ret;
 	}
 	if (sp->type == PORT_SCIFA || sp->type == PORT_SCIFB ||
-	    sp->type == PORT_HSCIF) {
+	    sp->type == PORT_HSCIF || sp->type == SCI_PORT_RSCI) {
 		ret = device_create_file(&dev->dev, &dev_attr_rx_fifo_timeout);
 		if (ret) {
 			if (sp->port.fifosize > 1) {
-- 
2.43.0

Re: [PATCH v10 07/10] serial: sh-sci: Add support for RZ/T2H SCI

[Geert Uytterhoeven]

On Fri, 23 May 2025 at 16:24, Thierry Bultel
<thierry.bultel.yh@bp.renesas.com> wrote:
> Define a new RSCI port type, and the RSCI 32 bits registers set.
> The RZ/T2H SCI has a a fifo, and a quite different set of registers
> from the original SH SCI ones.
> DMA is not supported yet.
>
> Reviewed-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
> Signed-off-by: Thierry Bultel <thierry.bultel.yh@bp.renesas.com>
> ---
> Changes v9->v10:
>   - removed unneed #ifdef in rsci.h
>   - use same error message in sci_init_clocks

LGTM, so
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>

Gr{oetje,eeting}s,

                        Geert

-- 
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds