[PATCH v7 2/2] Support 32-bit access for the TX/RX hold registers UTXH and URXH.

[PATCH v7 2/2] Support 32-bit access for the TX/RX hold registers UTXH and URXH.

[Hyunki Koo]

From: Hyunki Koo <hyunki00.koo@samsung.com>

This is required for some newer SoCs.

Signed-off-by: Hyunki Koo <hyunki00.koo@samsung.com>
Reviewed-by: Krzysztof Kozlowski <krzk@kernel.org>
Tested on Odroid HC1 (Exynos5422):
Tested-by: Krzysztof Kozlowski <krzk@kernel.org>
---
v2: 
line 954 : change rd_regl to rd_reg in for backward compatibility.
line 2031: Add init value for ourport->port.iotype  to UPIO_MEM 
v3:
line 2031: remove redundant init value  for ourport->port.iotype 
v4:
correct variable types and change misleading function name
v5:
add dt-binding and go as first patch in this series.
v6:
no change in this patch, only chaged in [PATCH v6 1/2]
v7:
add reviewed by and tested by
---
 drivers/tty/serial/samsung_tty.c | 76 +++++++++++++++++++++++++++-----
 1 file changed, 64 insertions(+), 12 deletions(-)

diff --git a/drivers/tty/serial/samsung_tty.c b/drivers/tty/serial/samsung_tty.c
index 73f951d65b93..bdf1d4d12cb1 100644
--- a/drivers/tty/serial/samsung_tty.c
+++ b/drivers/tty/serial/samsung_tty.c
@@ -154,12 +154,47 @@ struct s3c24xx_uart_port {
 #define portaddrl(port, reg) \
 	((unsigned long *)(unsigned long)((port)->membase + (reg)))
 
-#define rd_regb(port, reg) (readb_relaxed(portaddr(port, reg)))
+static u32 rd_reg(struct uart_port *port, u32 reg)
+{
+	switch (port->iotype) {
+	case UPIO_MEM:
+		return readb_relaxed(portaddr(port, reg));
+	case UPIO_MEM32:
+		return readl_relaxed(portaddr(port, reg));
+	default:
+		return 0;
+	}
+	return 0;
+}
+
 #define rd_regl(port, reg) (readl_relaxed(portaddr(port, reg)))
 
-#define wr_regb(port, reg, val) writeb_relaxed(val, portaddr(port, reg))
+static void wr_reg(struct uart_port *port, u32 reg, u32 val)
+{
+	switch (port->iotype) {
+	case UPIO_MEM:
+		writeb_relaxed(val, portaddr(port, reg));
+		break;
+	case UPIO_MEM32:
+		writel_relaxed(val, portaddr(port, reg));
+		break;
+	}
+}
+
 #define wr_regl(port, reg, val) writel_relaxed(val, portaddr(port, reg))
 
+static void wr_reg_barrier(struct uart_port *port, u32 reg, u32 val)
+{
+	switch (port->iotype) {
+	case UPIO_MEM:
+		writeb(val, portaddr(port, reg));
+		break;
+	case UPIO_MEM32:
+		writel(val, portaddr(port, reg));
+		break;
+	}
+}
+
 /* Byte-order aware bit setting/clearing functions. */
 
 static inline void s3c24xx_set_bit(struct uart_port *port, int idx,
@@ -714,7 +749,7 @@ static void s3c24xx_serial_rx_drain_fifo(struct s3c24xx_uart_port *ourport)
 		fifocnt--;
 
 		uerstat = rd_regl(port, S3C2410_UERSTAT);
-		ch = rd_regb(port, S3C2410_URXH);
+		ch = rd_reg(port, S3C2410_URXH);
 
 		if (port->flags & UPF_CONS_FLOW) {
 			int txe = s3c24xx_serial_txempty_nofifo(port);
@@ -826,7 +861,7 @@ static irqreturn_t s3c24xx_serial_tx_chars(int irq, void *id)
 	}
 
 	if (port->x_char) {
-		wr_regb(port, S3C2410_UTXH, port->x_char);
+		wr_reg(port, S3C2410_UTXH, port->x_char);
 		port->icount.tx++;
 		port->x_char = 0;
 		goto out;
@@ -852,7 +887,7 @@ static irqreturn_t s3c24xx_serial_tx_chars(int irq, void *id)
 		if (rd_regl(port, S3C2410_UFSTAT) & ourport->info->tx_fifofull)
 			break;
 
-		wr_regb(port, S3C2410_UTXH, xmit->buf[xmit->tail]);
+		wr_reg(port, S3C2410_UTXH, xmit->buf[xmit->tail]);
 		xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
 		port->icount.tx++;
 		count--;
@@ -916,7 +951,7 @@ static unsigned int s3c24xx_serial_tx_empty(struct uart_port *port)
 /* no modem control lines */
 static unsigned int s3c24xx_serial_get_mctrl(struct uart_port *port)
 {
-	unsigned int umstat = rd_regb(port, S3C2410_UMSTAT);
+	unsigned int umstat = rd_reg(port, S3C2410_UMSTAT);
 
 	if (umstat & S3C2410_UMSTAT_CTS)
 		return TIOCM_CAR | TIOCM_DSR | TIOCM_CTS;
@@ -1974,7 +2009,7 @@ static int s3c24xx_serial_probe(struct platform_device *pdev)
 	struct device_node *np = pdev->dev.of_node;
 	struct s3c24xx_uart_port *ourport;
 	int index = probe_index;
-	int ret;
+	int ret, prop = 0;
 
 	if (np) {
 		ret = of_alias_get_id(np, "serial");
@@ -2000,10 +2035,27 @@ static int s3c24xx_serial_probe(struct platform_device *pdev)
 			dev_get_platdata(&pdev->dev) :
 			ourport->drv_data->def_cfg;
 
-	if (np)
+	if (np) {
 		of_property_read_u32(np,
 			"samsung,uart-fifosize", &ourport->port.fifosize);
 
+		if (of_property_read_u32(np, "reg-io-width", &prop) == 0) {
+			switch (prop) {
+			case 1:
+				ourport->port.iotype = UPIO_MEM;
+				break;
+			case 4:
+				ourport->port.iotype = UPIO_MEM32;
+				break;
+			default:
+				dev_warn(&pdev->dev, "unsupported reg-io-width (%d)\n",
+						prop);
+				ret = -EINVAL;
+				break;
+			}
+		}
+	}
+
 	if (ourport->drv_data->fifosize[index])
 		ourport->port.fifosize = ourport->drv_data->fifosize[index];
 	else if (ourport->info->fifosize)
@@ -2185,7 +2237,7 @@ static int s3c24xx_serial_get_poll_char(struct uart_port *port)
 	if (s3c24xx_serial_rx_fifocnt(ourport, ufstat) == 0)
 		return NO_POLL_CHAR;
 
-	return rd_regb(port, S3C2410_URXH);
+	return rd_reg(port, S3C2410_URXH);
 }
 
 static void s3c24xx_serial_put_poll_char(struct uart_port *port,
@@ -2200,7 +2252,7 @@ static void s3c24xx_serial_put_poll_char(struct uart_port *port,
 
 	while (!s3c24xx_serial_console_txrdy(port, ufcon))
 		cpu_relax();
-	wr_regb(port, S3C2410_UTXH, c);
+	wr_reg(port, S3C2410_UTXH, c);
 }
 
 #endif /* CONFIG_CONSOLE_POLL */
@@ -2212,7 +2264,7 @@ s3c24xx_serial_console_putchar(struct uart_port *port, int ch)
 
 	while (!s3c24xx_serial_console_txrdy(port, ufcon))
 		cpu_relax();
-	wr_regb(port, S3C2410_UTXH, ch);
+	wr_reg(port, S3C2410_UTXH, ch);
 }
 
 static void
@@ -2612,7 +2664,7 @@ static void samsung_early_putc(struct uart_port *port, int c)
 	else
 		samsung_early_busyuart(port);
 
-	writeb(c, port->membase + S3C2410_UTXH);
+	wr_reg_barrier(port, S3C2410_UTXH, c);
 }
 
 static void samsung_early_write(struct console *con, const char *s,
-- 
2.17.1

[PATCH v7 1/2] dt-bindings: serial: add reg-io-width compatible

[Hyunki Koo]

From: Hyunki Koo <hyunki00.koo@samsung.com>

Add reg-io-width compatible

Signed-off-by: Hyunki Koo <hyunki00.koo@samsung.com>
Reviewed-by: Krzysztof Kozlowski <krzk@kernel.org>
---
v5: first added in this series
v6: clean description of reg-io-width
v7: correct build error on running 'make dt_binding_check' 
---
 .../devicetree/bindings/serial/samsung_uart.yaml          | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/Documentation/devicetree/bindings/serial/samsung_uart.yaml b/Documentation/devicetree/bindings/serial/samsung_uart.yaml
index 9d2ce347875b..a57b1233c691 100644
--- a/Documentation/devicetree/bindings/serial/samsung_uart.yaml
+++ b/Documentation/devicetree/bindings/serial/samsung_uart.yaml
@@ -29,6 +29,14 @@ properties:
   reg:
     maxItems: 1
 
+  reg-io-width:
+    description: |
+      The size (in bytes) of the IO accesses that should be performed
+      on the device.
+    allOf:
+      - $ref: /schemas/types.yaml#/definitions/uint32
+      - enum: [ 1, 4 ]
+
   clocks:
     minItems: 2
     maxItems: 5
-- 
2.17.1

Re: [PATCH v7 2/2] Support 32-bit access for the TX/RX hold registers UTXH and URXH.

[Greg KH]

On Sat, Apr 11, 2020 at 09:33:24PM +0900, Hyunki Koo wrote:
> From: Hyunki Koo <hyunki00.koo@samsung.com>
> 
> This is required for some newer SoCs.
> 
> Signed-off-by: Hyunki Koo <hyunki00.koo@samsung.com>
> Reviewed-by: Krzysztof Kozlowski <krzk@kernel.org>
> Tested on Odroid HC1 (Exynos5422):
> Tested-by: Krzysztof Kozlowski <krzk@kernel.org>
> ---
> v2: 
> line 954 : change rd_regl to rd_reg in for backward compatibility.
> line 2031: Add init value for ourport->port.iotype  to UPIO_MEM 
> v3:
> line 2031: remove redundant init value  for ourport->port.iotype 
> v4:
> correct variable types and change misleading function name
> v5:
> add dt-binding and go as first patch in this series.
> v6:
> no change in this patch, only chaged in [PATCH v6 1/2]
> v7:
> add reviewed by and tested by
> ---

Your subject line changed for this and patch 2 :(

Also, I asked you to split this patch up better in the past, you seem to
have ignored that :(

First patch would be to create the new functions and use them, with no
functional change to the code as-is.  A second patch would add the new
binding, and a third patch would be to add the new functionality.

And you need to describe all of this very well in your changelog, the
one sentence here is not sufficient at all.

Please fix this all up and resend.

thanks,

greg k-h

RE: [PATCH v7 2/2] Support 32-bit access for the TX/RX hold registers UTXH and URXH.

[Hyunki Koo]

On Thu, Apr 16, 2020 at 10:56:24PM +0900, Greg KH wrote:
> On Sat, Apr 11, 2020 at 09:33:24PM +0900, Hyunki Koo wrote:
> > From: Hyunki Koo <hyunki00.koo@samsung.com>
> >
> > This is required for some newer SoCs.
> >
> > Signed-off-by: Hyunki Koo <hyunki00.koo@samsung.com>
> > Reviewed-by: Krzysztof Kozlowski <krzk@kernel.org> Tested on Odroid
> > HC1 (Exynos5422):
> > Tested-by: Krzysztof Kozlowski <krzk@kernel.org>
> > ---
> > v2:
> > line 954 : change rd_regl to rd_reg in for backward compatibility.
> > line 2031: Add init value for ourport->port.iotype  to UPIO_MEM
> > v3:
> > line 2031: remove redundant init value  for ourport->port.iotype
> > v4:
> > correct variable types and change misleading function name
> > v5:
> > add dt-binding and go as first patch in this series.
> > v6:
> > no change in this patch, only chaged in [PATCH v6 1/2]
> > v7:
> > add reviewed by and tested by
> > ---
> 
> Your subject line changed for this and patch 2 :(
> 
> Also, I asked you to split this patch up better in the past, you seem to have
> ignored that :(
> 
> First patch would be to create the new functions and use them, with no
> functional change to the code as-is.  A second patch would add the new
> binding, and a third patch would be to add the new functionality.
> 
> And you need to describe all of this very well in your changelog, the one
> sentence here is not sufficient at all.
> 
> Please fix this all up and resend.
> 
> thanks,
> 
> greg k-h

Sorry I missed your comment in V4, I will split and update the patch and re-send.