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* [PATCH v2] serial: 8250: Add Nuvoton NPCM UART
@ 2018-02-15  2:17 Joel Stanley
  2018-02-19  3:16 ` Rob Herring
  2018-02-28 12:37 ` Greg Kroah-Hartman
  0 siblings, 2 replies; 4+ messages in thread
From: Joel Stanley @ 2018-02-15  2:17 UTC (permalink / raw)
  To: Greg Kroah-Hartman, Rob Herring, Mark Rutland
  Cc: linux-serial-u79uwXL29TY76Z2rM5mHXA,
	devicetree-u79uwXL29TY76Z2rM5mHXA,
	linux-kernel-u79uwXL29TY76Z2rM5mHXA, Tomer Maimon, Avi Fishman,
	Jeremy Kerr

The Nuvoton UART is almost compatible with the 8250 driver when probed
via the 8250_of driver, however it requires some extra configuration
at startup.

Signed-off-by: Joel Stanley <joel-U3u1mxZcP9KHXe+LvDLADg@public.gmane.org>
---
v2:
 Remove redundant whitespace
 Use port number 40 to fill in a gap

 Documentation/devicetree/bindings/serial/8250.txt |  1 +
 drivers/tty/serial/8250/8250_of.c                 |  1 +
 drivers/tty/serial/8250/8250_port.c               | 29 +++++++++++++++++++++++
 include/uapi/linux/serial_core.h                  |  3 +++
 include/uapi/linux/serial_reg.h                   |  5 ++++
 5 files changed, 39 insertions(+)

diff --git a/Documentation/devicetree/bindings/serial/8250.txt b/Documentation/devicetree/bindings/serial/8250.txt
index dad3b2ec66d4..aeb6db4e35c3 100644
--- a/Documentation/devicetree/bindings/serial/8250.txt
+++ b/Documentation/devicetree/bindings/serial/8250.txt
@@ -24,6 +24,7 @@ Required properties:
 	- "ti,da830-uart"
 	- "aspeed,ast2400-vuart"
 	- "aspeed,ast2500-vuart"
+	- "nuvoton,npcm750-uart"
 	- "serial" if the port type is unknown.
 - reg : offset and length of the register set for the device.
 - interrupts : should contain uart interrupt.
diff --git a/drivers/tty/serial/8250/8250_of.c b/drivers/tty/serial/8250/8250_of.c
index 160b8906d9b9..9835b1c1cbe1 100644
--- a/drivers/tty/serial/8250/8250_of.c
+++ b/drivers/tty/serial/8250/8250_of.c
@@ -316,6 +316,7 @@ static const struct of_device_id of_platform_serial_table[] = {
 	{ .compatible = "mrvl,mmp-uart",
 		.data = (void *)PORT_XSCALE, },
 	{ .compatible = "ti,da830-uart", .data = (void *)PORT_DA830, },
+	{ .compatible = "nuvoton,npcm750-uart", .data = (void *)PORT_NPCM, },
 	{ /* end of list */ },
 };
 MODULE_DEVICE_TABLE(of, of_platform_serial_table);
diff --git a/drivers/tty/serial/8250/8250_port.c b/drivers/tty/serial/8250/8250_port.c
index 1328c7e70108..a72222f8b005 100644
--- a/drivers/tty/serial/8250/8250_port.c
+++ b/drivers/tty/serial/8250/8250_port.c
@@ -293,6 +293,15 @@ static const struct serial8250_config uart_config[] = {
 				  UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT,
 		.flags		= UART_CAP_FIFO,
 	},
+	[PORT_NPCM] = {
+		.name		= "Nuvoton 16550",
+		.fifo_size	= 16,
+		.tx_loadsz	= 16,
+		.fcr		= UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_10 |
+				  UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT,
+		.rxtrig_bytes	= {1, 4, 8, 14},
+		.flags		= UART_CAP_FIFO,
+	},
 };
 
 /* Uart divisor latch read */
@@ -2140,6 +2149,15 @@ int serial8250_do_startup(struct uart_port *port)
 				UART_DA830_PWREMU_MGMT_FREE);
 	}
 
+	if (port->type == PORT_NPCM) {
+		/*
+		 * Nuvoton calls the scratch register 'UART_TOR' (timeout
+		 * register). Enable it, and set TIOC (timeout interrupt
+		 * comparator) to be 0x20 for correct operation.
+		 */
+		serial_port_out(port, UART_NPCM_TOR, UART_NPCM_TOIE | 0x20);
+	}
+
 #ifdef CONFIG_SERIAL_8250_RSA
 	/*
 	 * If this is an RSA port, see if we can kick it up to the
@@ -2462,6 +2480,15 @@ static unsigned int xr17v35x_get_divisor(struct uart_8250_port *up,
 	return quot_16 >> 4;
 }
 
+/* Nuvoton NPCM UARTs have a custom divisor calculation */
+static unsigned int npcm_get_divisor(struct uart_8250_port *up,
+		unsigned int baud)
+{
+	struct uart_port *port = &up->port;
+
+	return DIV_ROUND_CLOSEST(port->uartclk, 16 * baud + 2) - 2;
+}
+
 static unsigned int serial8250_get_divisor(struct uart_8250_port *up,
 					   unsigned int baud,
 					   unsigned int *frac)
@@ -2482,6 +2509,8 @@ static unsigned int serial8250_get_divisor(struct uart_8250_port *up,
 		quot = 0x8002;
 	else if (up->port.type == PORT_XR17V35X)
 		quot = xr17v35x_get_divisor(up, baud, frac);
+	else if (up->port.type == PORT_NPCM)
+		quot = npcm_get_divisor(up, baud);
 	else
 		quot = uart_get_divisor(port, baud);
 
diff --git a/include/uapi/linux/serial_core.h b/include/uapi/linux/serial_core.h
index 1c8413f93e3d..dce5f9dae121 100644
--- a/include/uapi/linux/serial_core.h
+++ b/include/uapi/linux/serial_core.h
@@ -76,6 +76,9 @@
 #define PORT_SUNZILOG	38
 #define PORT_SUNSAB	39
 
+/* Nuvoton UART */
+#define PORT_NPCM	40
+
 /* Intel EG20 */
 #define PORT_PCH_8LINE	44
 #define PORT_PCH_2LINE	45
diff --git a/include/uapi/linux/serial_reg.h b/include/uapi/linux/serial_reg.h
index be07b5470f4b..f82f3c869df9 100644
--- a/include/uapi/linux/serial_reg.h
+++ b/include/uapi/linux/serial_reg.h
@@ -376,5 +376,10 @@
 #define UART_ALTR_EN_TXFIFO_LW	0x01	/* Enable the TX FIFO Low Watermark */
 #define UART_ALTR_TX_LOW	0x41	/* Tx FIFO Low Watermark */
 
+
+/* Nuvoton NPCM timeout register */
+#define UART_NPCM_TOR		7
+#define UART_NPCM_TOIE		BIT(7)	/* Timeout Interrupt Enable */
+
 #endif /* _LINUX_SERIAL_REG_H */
 
-- 
2.15.1

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^ permalink raw reply related	[flat|nested] 4+ messages in thread
* Re: [PATCH v2] serial: 8250: Add Nuvoton NPCM UART
  2018-02-15  2:17 [PATCH v2] serial: 8250: Add Nuvoton NPCM UART Joel Stanley
@ 2018-02-19  3:16 ` Rob Herring
  2018-02-28 12:37 ` Greg Kroah-Hartman
  1 sibling, 0 replies; 4+ messages in thread
From: Rob Herring @ 2018-02-19  3:16 UTC (permalink / raw)
  To: Joel Stanley
  Cc: Greg Kroah-Hartman, Mark Rutland, linux-serial, devicetree,
	linux-kernel, Tomer Maimon, Avi Fishman, Jeremy Kerr

On Thu, Feb 15, 2018 at 12:47:20PM +1030, Joel Stanley wrote:
> The Nuvoton UART is almost compatible with the 8250 driver when probed
> via the 8250_of driver, however it requires some extra configuration
> at startup.
> 
> Signed-off-by: Joel Stanley <joel@jms.id.au>
> ---
> v2:
>  Remove redundant whitespace
>  Use port number 40 to fill in a gap
> 
>  Documentation/devicetree/bindings/serial/8250.txt |  1 +

Reviewed-by: Rob Herring <robh@kernel.org>

>  drivers/tty/serial/8250/8250_of.c                 |  1 +
>  drivers/tty/serial/8250/8250_port.c               | 29 +++++++++++++++++++++++
>  include/uapi/linux/serial_core.h                  |  3 +++
>  include/uapi/linux/serial_reg.h                   |  5 ++++
>  5 files changed, 39 insertions(+)

^ permalink raw reply	[flat|nested] 4+ messages in thread
* Re: [PATCH v2] serial: 8250: Add Nuvoton NPCM UART
  2018-02-15  2:17 [PATCH v2] serial: 8250: Add Nuvoton NPCM UART Joel Stanley
  2018-02-19  3:16 ` Rob Herring
@ 2018-02-28 12:37 ` Greg Kroah-Hartman
  1 sibling, 0 replies; 4+ messages in thread
From: Greg Kroah-Hartman @ 2018-02-28 12:37 UTC (permalink / raw)
  To: Joel Stanley
  Cc: Rob Herring, Mark Rutland, linux-serial, devicetree,
	linux-kernel, Tomer Maimon, Avi Fishman, Jeremy Kerr

On Thu, Feb 15, 2018 at 12:47:20PM +1030, Joel Stanley wrote:
> The Nuvoton UART is almost compatible with the 8250 driver when probed
> via the 8250_of driver, however it requires some extra configuration
> at startup.
> 
> Signed-off-by: Joel Stanley <joel@jms.id.au>
> Reviewed-by: Rob Herring <robh@kernel.org>
> ---
> v2:
>  Remove redundant whitespace
>  Use port number 40 to fill in a gap
> 
>  Documentation/devicetree/bindings/serial/8250.txt |  1 +
>  drivers/tty/serial/8250/8250_of.c                 |  1 +
>  drivers/tty/serial/8250/8250_port.c               | 29 +++++++++++++++++++++++
>  include/uapi/linux/serial_core.h                  |  3 +++
>  include/uapi/linux/serial_reg.h                   |  5 ++++
>  5 files changed, 39 insertions(+)
> 
> diff --git a/Documentation/devicetree/bindings/serial/8250.txt b/Documentation/devicetree/bindings/serial/8250.txt
> index dad3b2ec66d4..aeb6db4e35c3 100644
> --- a/Documentation/devicetree/bindings/serial/8250.txt
> +++ b/Documentation/devicetree/bindings/serial/8250.txt
> @@ -24,6 +24,7 @@ Required properties:
>  	- "ti,da830-uart"
>  	- "aspeed,ast2400-vuart"
>  	- "aspeed,ast2500-vuart"
> +	- "nuvoton,npcm750-uart"
>  	- "serial" if the port type is unknown.
>  - reg : offset and length of the register set for the device.
>  - interrupts : should contain uart interrupt.
> diff --git a/drivers/tty/serial/8250/8250_of.c b/drivers/tty/serial/8250/8250_of.c
> index 160b8906d9b9..9835b1c1cbe1 100644
> --- a/drivers/tty/serial/8250/8250_of.c
> +++ b/drivers/tty/serial/8250/8250_of.c
> @@ -316,6 +316,7 @@ static const struct of_device_id of_platform_serial_table[] = {
>  	{ .compatible = "mrvl,mmp-uart",
>  		.data = (void *)PORT_XSCALE, },
>  	{ .compatible = "ti,da830-uart", .data = (void *)PORT_DA830, },
> +	{ .compatible = "nuvoton,npcm750-uart", .data = (void *)PORT_NPCM, },
>  	{ /* end of list */ },
>  };
>  MODULE_DEVICE_TABLE(of, of_platform_serial_table);
> diff --git a/drivers/tty/serial/8250/8250_port.c b/drivers/tty/serial/8250/8250_port.c
> index 1328c7e70108..a72222f8b005 100644
> --- a/drivers/tty/serial/8250/8250_port.c
> +++ b/drivers/tty/serial/8250/8250_port.c
> @@ -293,6 +293,15 @@ static const struct serial8250_config uart_config[] = {
>  				  UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT,
>  		.flags		= UART_CAP_FIFO,
>  	},
> +	[PORT_NPCM] = {
> +		.name		= "Nuvoton 16550",
> +		.fifo_size	= 16,
> +		.tx_loadsz	= 16,
> +		.fcr		= UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_10 |
> +				  UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT,
> +		.rxtrig_bytes	= {1, 4, 8, 14},
> +		.flags		= UART_CAP_FIFO,
> +	},
>  };
>  
>  /* Uart divisor latch read */
> @@ -2140,6 +2149,15 @@ int serial8250_do_startup(struct uart_port *port)
>  				UART_DA830_PWREMU_MGMT_FREE);
>  	}
>  
> +	if (port->type == PORT_NPCM) {
> +		/*
> +		 * Nuvoton calls the scratch register 'UART_TOR' (timeout
> +		 * register). Enable it, and set TIOC (timeout interrupt
> +		 * comparator) to be 0x20 for correct operation.
> +		 */
> +		serial_port_out(port, UART_NPCM_TOR, UART_NPCM_TOIE | 0x20);
> +	}
> +
>  #ifdef CONFIG_SERIAL_8250_RSA
>  	/*
>  	 * If this is an RSA port, see if we can kick it up to the
> @@ -2462,6 +2480,15 @@ static unsigned int xr17v35x_get_divisor(struct uart_8250_port *up,
>  	return quot_16 >> 4;
>  }
>  
> +/* Nuvoton NPCM UARTs have a custom divisor calculation */
> +static unsigned int npcm_get_divisor(struct uart_8250_port *up,
> +		unsigned int baud)
> +{
> +	struct uart_port *port = &up->port;
> +
> +	return DIV_ROUND_CLOSEST(port->uartclk, 16 * baud + 2) - 2;
> +}
> +
>  static unsigned int serial8250_get_divisor(struct uart_8250_port *up,
>  					   unsigned int baud,
>  					   unsigned int *frac)
> @@ -2482,6 +2509,8 @@ static unsigned int serial8250_get_divisor(struct uart_8250_port *up,
>  		quot = 0x8002;
>  	else if (up->port.type == PORT_XR17V35X)
>  		quot = xr17v35x_get_divisor(up, baud, frac);
> +	else if (up->port.type == PORT_NPCM)
> +		quot = npcm_get_divisor(up, baud);
>  	else
>  		quot = uart_get_divisor(port, baud);
>  
> diff --git a/include/uapi/linux/serial_core.h b/include/uapi/linux/serial_core.h
> index 1c8413f93e3d..dce5f9dae121 100644
> --- a/include/uapi/linux/serial_core.h
> +++ b/include/uapi/linux/serial_core.h
> @@ -76,6 +76,9 @@
>  #define PORT_SUNZILOG	38
>  #define PORT_SUNSAB	39
>  
> +/* Nuvoton UART */
> +#define PORT_NPCM	40
> +
>  /* Intel EG20 */
>  #define PORT_PCH_8LINE	44
>  #define PORT_PCH_2LINE	45
> diff --git a/include/uapi/linux/serial_reg.h b/include/uapi/linux/serial_reg.h
> index be07b5470f4b..f82f3c869df9 100644
> --- a/include/uapi/linux/serial_reg.h
> +++ b/include/uapi/linux/serial_reg.h
> @@ -376,5 +376,10 @@
>  #define UART_ALTR_EN_TXFIFO_LW	0x01	/* Enable the TX FIFO Low Watermark */
>  #define UART_ALTR_TX_LOW	0x41	/* Tx FIFO Low Watermark */
>  
> +
> +/* Nuvoton NPCM timeout register */
> +#define UART_NPCM_TOR		7
> +#define UART_NPCM_TOIE		BIT(7)	/* Timeout Interrupt Enable */

Why is this needed in a userspace api file?  That feels very odd for
just a new device.  Please put this somewhere internal.

thanks,

greg k-h

^ permalink raw reply	[flat|nested] 4+ messages in thread
* [PATCH v2] serial: 8250: Add Nuvoton NPCM UART
@ 2018-03-05 11:47 Joel Stanley
  0 siblings, 0 replies; 4+ messages in thread
From: Joel Stanley @ 2018-03-05 11:47 UTC (permalink / raw)
  To: Greg Kroah-Hartman, Rob Herring, Mark Rutland
  Cc: linux-serial, devicetree, linux-kernel, Tomer Maimon,
	Avi Fishman, Jeremy Kerr

The Nuvoton UART is almost compatible with the 8250 driver when probed
via the 8250_of driver, however it requires some extra configuration
at startup.

Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Joel Stanley <joel@jms.id.au>
---
v2:
 Remove redundant whitespace
 Use port number 40 to fill in a gap
v3:
 Remove some whitespace in serial_reg.h
 Move UART_NPCM_TOR and UART_NPCM_TOIE out of userspace header
 Add Rob's review
---
 Documentation/devicetree/bindings/serial/8250.txt |  1 +
 drivers/tty/serial/8250/8250_of.c                 |  1 +
 drivers/tty/serial/8250/8250_port.c               | 33 +++++++++++++++++++++++
 include/uapi/linux/serial_core.h                  |  3 +++
 4 files changed, 38 insertions(+)

diff --git a/Documentation/devicetree/bindings/serial/8250.txt b/Documentation/devicetree/bindings/serial/8250.txt
index dad3b2ec66d4..aeb6db4e35c3 100644
--- a/Documentation/devicetree/bindings/serial/8250.txt
+++ b/Documentation/devicetree/bindings/serial/8250.txt
@@ -24,6 +24,7 @@ Required properties:
 	- "ti,da830-uart"
 	- "aspeed,ast2400-vuart"
 	- "aspeed,ast2500-vuart"
+	- "nuvoton,npcm750-uart"
 	- "serial" if the port type is unknown.
 - reg : offset and length of the register set for the device.
 - interrupts : should contain uart interrupt.
diff --git a/drivers/tty/serial/8250/8250_of.c b/drivers/tty/serial/8250/8250_of.c
index 160b8906d9b9..9835b1c1cbe1 100644
--- a/drivers/tty/serial/8250/8250_of.c
+++ b/drivers/tty/serial/8250/8250_of.c
@@ -316,6 +316,7 @@ static const struct of_device_id of_platform_serial_table[] = {
 	{ .compatible = "mrvl,mmp-uart",
 		.data = (void *)PORT_XSCALE, },
 	{ .compatible = "ti,da830-uart", .data = (void *)PORT_DA830, },
+	{ .compatible = "nuvoton,npcm750-uart", .data = (void *)PORT_NPCM, },
 	{ /* end of list */ },
 };
 MODULE_DEVICE_TABLE(of, of_platform_serial_table);
diff --git a/drivers/tty/serial/8250/8250_port.c b/drivers/tty/serial/8250/8250_port.c
index 1328c7e70108..804c1af6fd33 100644
--- a/drivers/tty/serial/8250/8250_port.c
+++ b/drivers/tty/serial/8250/8250_port.c
@@ -47,6 +47,10 @@
 #define UART_EXAR_SLEEP		0x8b	/* Sleep mode */
 #define UART_EXAR_DVID		0x8d	/* Device identification */
 
+/* Nuvoton NPCM timeout register */
+#define UART_NPCM_TOR          7
+#define UART_NPCM_TOIE         BIT(7)  /* Timeout Interrupt Enable */
+
 /*
  * Debugging.
  */
@@ -293,6 +297,15 @@ static const struct serial8250_config uart_config[] = {
 				  UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT,
 		.flags		= UART_CAP_FIFO,
 	},
+	[PORT_NPCM] = {
+		.name		= "Nuvoton 16550",
+		.fifo_size	= 16,
+		.tx_loadsz	= 16,
+		.fcr		= UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_10 |
+				  UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT,
+		.rxtrig_bytes	= {1, 4, 8, 14},
+		.flags		= UART_CAP_FIFO,
+	},
 };
 
 /* Uart divisor latch read */
@@ -2140,6 +2153,15 @@ int serial8250_do_startup(struct uart_port *port)
 				UART_DA830_PWREMU_MGMT_FREE);
 	}
 
+	if (port->type == PORT_NPCM) {
+		/*
+		 * Nuvoton calls the scratch register 'UART_TOR' (timeout
+		 * register). Enable it, and set TIOC (timeout interrupt
+		 * comparator) to be 0x20 for correct operation.
+		 */
+		serial_port_out(port, UART_NPCM_TOR, UART_NPCM_TOIE | 0x20);
+	}
+
 #ifdef CONFIG_SERIAL_8250_RSA
 	/*
 	 * If this is an RSA port, see if we can kick it up to the
@@ -2462,6 +2484,15 @@ static unsigned int xr17v35x_get_divisor(struct uart_8250_port *up,
 	return quot_16 >> 4;
 }
 
+/* Nuvoton NPCM UARTs have a custom divisor calculation */
+static unsigned int npcm_get_divisor(struct uart_8250_port *up,
+		unsigned int baud)
+{
+	struct uart_port *port = &up->port;
+
+	return DIV_ROUND_CLOSEST(port->uartclk, 16 * baud + 2) - 2;
+}
+
 static unsigned int serial8250_get_divisor(struct uart_8250_port *up,
 					   unsigned int baud,
 					   unsigned int *frac)
@@ -2482,6 +2513,8 @@ static unsigned int serial8250_get_divisor(struct uart_8250_port *up,
 		quot = 0x8002;
 	else if (up->port.type == PORT_XR17V35X)
 		quot = xr17v35x_get_divisor(up, baud, frac);
+	else if (up->port.type == PORT_NPCM)
+		quot = npcm_get_divisor(up, baud);
 	else
 		quot = uart_get_divisor(port, baud);
 
diff --git a/include/uapi/linux/serial_core.h b/include/uapi/linux/serial_core.h
index 1c8413f93e3d..dce5f9dae121 100644
--- a/include/uapi/linux/serial_core.h
+++ b/include/uapi/linux/serial_core.h
@@ -76,6 +76,9 @@
 #define PORT_SUNZILOG	38
 #define PORT_SUNSAB	39
 
+/* Nuvoton UART */
+#define PORT_NPCM	40
+
 /* Intel EG20 */
 #define PORT_PCH_8LINE	44
 #define PORT_PCH_2LINE	45
-- 
2.15.1

^ permalink raw reply related	[flat|nested] 4+ messages in thread
end of thread, other threads:[~2018-03-05 11:47 UTC | newest]

Thread overview: 4+ messages (download: mbox.gz / follow: Atom feed)
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2018-02-15  2:17 [PATCH v2] serial: 8250: Add Nuvoton NPCM UART Joel Stanley
2018-02-19  3:16 ` Rob Herring
2018-02-28 12:37 ` Greg Kroah-Hartman
2018-03-05 11:47 Joel Stanley

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