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* [PATCH v2 00/16] Support armada-37xx second UART port
@ 2017-10-13  9:01 Miquel Raynal
  2017-10-13  9:01 ` [PATCH v2 01/16] dt-bindings: mvebu-uart: update documentation with extended UART Miquel Raynal
                   ` (15 more replies)
  0 siblings, 16 replies; 29+ messages in thread
From: Miquel Raynal @ 2017-10-13  9:01 UTC (permalink / raw)
  To: linux-arm-kernel

Changes since v1:
- Added a fallback in probe() to allow the use of this driver without
  device tree.
- Used devm_free_irq() instead of free_irq().
- Changed comments on ESPRESSObin DTS.
- Fixed various typos.
- Added Gregory's Acked-by/Reviewed-by tags.


Hi,

This series adds support for the armada-37xx extended UART port. The new
capabilities of this IP compared to the standard port are the possibility
to use DMA, it has bigger FIFOs (128 bytes instead of 32/64), it is
possible to fill the FIFO byte-per-byte or 4 bytes at a time, it as RTS
and CTS control, it supports transfer count for RX/TX with transfer
finish status and finally it may achieve higher baudrates by the use of
special dividers.

Almost none of these extended features are implemented though. For now,
the extended UART is just supported with the same features as the
standard UART.

This IP is present on the Armada 3720 SoC and is now enabled by the
device tree related patches on the Armada-3720-DB. As adding the node to
enable the second port on Armada-3720-ESPRESSObin could break existing
users by changing the configuration of some pins on the main headers,
only a side note is added on how to do it easily.

- The driver patches should go through Greg KH.
- The DT patches should go through the mvebu maintainers.
- We would also like the DT binding documentation update to go through
  the mvebu maintainers, as it conflicts with another DT change.

Thank you,
Miquel


Allen Yan (5):
  serial: mvebu-uart: support probe of multiple ports
  serial: mvebu-uart: add soft reset at probe
  serial: mvebu-uart: add function to change baudrate
  serial: mvebu-uart: clear state register before IRQ request
  serial: mvebu-uart: add TX interrupt trigger for pulse interrupts

Miquel Raynal (10):
  dt-bindings: mvebu-uart: update documentation with extended UART
  pinctrl: dt-bindings: Fix A37xx uart2 group name
  serial: mvebu-uart: use a generic way to access the registers
  serial: mvebu-uart: dissociate RX and TX interrupts
  serial: mvebu-uart: augment the maximum number of ports
  serial: mvebu-uart: support extended port registers layout
  arm64: dts: marvell: armada-37xx: add UART clock
  arm64: dts: marvell: armada-37xx: add second UART port
  arm64: dts: marvell: armada-3720-db: enable second UART port
  arm64: dts: marvell: armada-3720-espressobin: fill UART nodes

Yehuda Yitschak (1):
  serial: mvebu-uart: use driver name when requesting an interrupt

 .../pinctrl/marvell,armada-37xx-pinctrl.txt        |   4 +-
 .../devicetree/bindings/serial/mvebu-uart.txt      |  49 ++-
 arch/arm64/boot/dts/marvell/armada-3720-db.dts     |   9 +-
 .../boot/dts/marvell/armada-3720-espressobin.dts   |  12 +
 arch/arm64/boot/dts/marvell/armada-37xx.dtsi       |  19 +-
 drivers/tty/serial/mvebu-uart.c                    | 483 +++++++++++++++++----
 6 files changed, 473 insertions(+), 103 deletions(-)

-- 
2.11.0

^ permalink raw reply	[flat|nested] 29+ messages in thread

* [PATCH v2 01/16] dt-bindings: mvebu-uart: update documentation with extended UART
  2017-10-13  9:01 [PATCH v2 00/16] Support armada-37xx second UART port Miquel Raynal
@ 2017-10-13  9:01 ` Miquel Raynal
  2017-10-17 22:00   ` Rob Herring
  2017-10-13  9:01 ` [PATCH v2 02/16] pinctrl: dt-bindings: Fix A37xx uart2 group name Miquel Raynal
                   ` (14 subsequent siblings)
  15 siblings, 1 reply; 29+ messages in thread
From: Miquel Raynal @ 2017-10-13  9:01 UTC (permalink / raw)
  To: linux-arm-kernel

Update the Device Tree binding documentation for the Marvell EBU UART,
in order to allow describing the extended UART IP block, in addition to
the already supported standard UART IP. This requires adding a new
compatible string, the introduction of a clocks property, and extensions
to the interrupts property.

Signed-off-by: Miquel Raynal <miquel.raynal@free-electrons.com>
Reviewed-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
---
 .../devicetree/bindings/serial/mvebu-uart.txt      | 49 +++++++++++++++++++---
 1 file changed, 44 insertions(+), 5 deletions(-)

diff --git a/Documentation/devicetree/bindings/serial/mvebu-uart.txt b/Documentation/devicetree/bindings/serial/mvebu-uart.txt
index d37fabe17bd1..3df3a3fab4bb 100644
--- a/Documentation/devicetree/bindings/serial/mvebu-uart.txt
+++ b/Documentation/devicetree/bindings/serial/mvebu-uart.txt
@@ -1,13 +1,52 @@
-* Marvell UART : Non standard UART used in some of Marvell EBU SoCs (e.g., Armada-3700)
+* Marvell UART : Non standard UART used in some of Marvell EBU SoCs
+                 e.g., Armada-3700.
 
 Required properties:
-- compatible: "marvell,armada-3700-uart"
+- compatible:
+    - "marvell,armada-3700-uart" for the standard variant of the UART
+      (32 bytes FIFO, no DMA, level interrupts, 8-bit access to the
+      FIFO, baudrate limited to 230400).
+    - "marvell,armada-3700-uart-ext" for the extended variant of the
+      UART (128 bytes FIFO, DMA, front interrupts, 8-bit or 32-bit
+      accesses to the FIFO, baudrate unlimited by the dividers).
 - reg: offset and length of the register set for the device.
-- interrupts: device interrupt
+- clocks: UART reference clock used to derive the baudrate (only
+      mandatory with "marvell,armada-3700-uart-ext" compatible).
+- interrupts:
+    - Must contain three elements for the standard variant of the IP
+      (marvell,armada-3700-uart): "uart-sum", "uart-tx" and "uart-rx",
+      respectively the UART sum interrupt, the UART TX interrupt and
+      UART RX interrupt. A corresponding interrupt-names property must
+      be defined.
+    - Must contain two elements for the extended variant of the IP
+      (marvell,armada-3700-uart-ext): "uart-tx" and "uart-rx",
+      respectively the UART TX interrupt and the UART RX interrupt. A
+      corresponding interrupts-names property must be defined.
+    - For backward compatibility reasons, a single element interrupts
+      property is also supported for the standard variant of the IP,
+      containing only the UART sum interrupt. This form is deprecated
+      and should no longer be used.
 
 Example:
-	serial at 12000 {
+	uart0: serial at 12000 {
 		compatible = "marvell,armada-3700-uart";
 		reg = <0x12000 0x200>;
-		interrupts = <43>;
+		clocks = <&xtalclk>;
+		interrupts =
+		<GIC_SPI 11 IRQ_TYPE_LEVEL_HIGH>,
+		<GIC_SPI 12 IRQ_TYPE_LEVEL_HIGH>,
+		<GIC_SPI 13 IRQ_TYPE_LEVEL_HIGH>;
+		interrupt-names = "uart-sum", "uart-tx", "uart-rx";
+		status = "disabled";
+	};
+
+	uart1: serial at 12200 {
+		compatible = "marvell,armada-3700-uart-ext";
+		reg = <0x12200 0x30>;
+		clocks = <&xtalclk>;
+		interrupts =
+		<GIC_SPI 30 IRQ_TYPE_EDGE_RISING>,
+		<GIC_SPI 31 IRQ_TYPE_EDGE_RISING>;
+		interrupt-names = "uart-tx", "uart-rx";
+		status = "disabled";
 	};
-- 
2.11.0

^ permalink raw reply related	[flat|nested] 29+ messages in thread

* [PATCH v2 02/16] pinctrl: dt-bindings: Fix A37xx uart2 group name
  2017-10-13  9:01 [PATCH v2 00/16] Support armada-37xx second UART port Miquel Raynal
  2017-10-13  9:01 ` [PATCH v2 01/16] dt-bindings: mvebu-uart: update documentation with extended UART Miquel Raynal
@ 2017-10-13  9:01 ` Miquel Raynal
  2017-10-16 11:56   ` Linus Walleij
  2017-10-13  9:01 ` [PATCH v2 03/16] serial: mvebu-uart: use driver name when requesting an interrupt Miquel Raynal
                   ` (13 subsequent siblings)
  15 siblings, 1 reply; 29+ messages in thread
From: Miquel Raynal @ 2017-10-13  9:01 UTC (permalink / raw)
  To: linux-arm-kernel

Fix a typo in A37xx pin controllers documentation about uart2 pin group.

Signed-off-by: Miquel Raynal <miquel.raynal@free-electrons.com>
Reviewed-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
---
 .../devicetree/bindings/pinctrl/marvell,armada-37xx-pinctrl.txt       | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/Documentation/devicetree/bindings/pinctrl/marvell,armada-37xx-pinctrl.txt b/Documentation/devicetree/bindings/pinctrl/marvell,armada-37xx-pinctrl.txt
index f64060908d5a..c7c088d2dd50 100644
--- a/Documentation/devicetree/bindings/pinctrl/marvell,armada-37xx-pinctrl.txt
+++ b/Documentation/devicetree/bindings/pinctrl/marvell,armada-37xx-pinctrl.txt
@@ -97,8 +97,8 @@ group spi_quad
  - pins 15-16
  - functions spi, gpio
 
-group uart_2
- - pins 9-10
+group uart2
+ - pins 9-10 and 18-19
  - functions uart, gpio
 
 Available groups and functions for the South bridge:
-- 
2.11.0

^ permalink raw reply related	[flat|nested] 29+ messages in thread

* [PATCH v2 03/16] serial: mvebu-uart: use driver name when requesting an interrupt
  2017-10-13  9:01 [PATCH v2 00/16] Support armada-37xx second UART port Miquel Raynal
  2017-10-13  9:01 ` [PATCH v2 01/16] dt-bindings: mvebu-uart: update documentation with extended UART Miquel Raynal
  2017-10-13  9:01 ` [PATCH v2 02/16] pinctrl: dt-bindings: Fix A37xx uart2 group name Miquel Raynal
@ 2017-10-13  9:01 ` Miquel Raynal
  2017-10-13  9:01 ` [PATCH v2 04/16] serial: mvebu-uart: support probe of multiple ports Miquel Raynal
                   ` (12 subsequent siblings)
  15 siblings, 0 replies; 29+ messages in thread
From: Miquel Raynal @ 2017-10-13  9:01 UTC (permalink / raw)
  To: linux-arm-kernel

From: Yehuda Yitschak <yehuday@marvell.com>

Use the driver name when requesting an interrupt for consistency.

Avoids possible confusion with DW8250 driver interrupt names in
/proc/interrupts.

Signed-off-by: Yehuda Yitschak <yehuday@marvell.com>
Signed-off-by: Miquel Raynal <miquel.raynal@free-electrons.com>
Reviewed-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
---
 drivers/tty/serial/mvebu-uart.c | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/drivers/tty/serial/mvebu-uart.c b/drivers/tty/serial/mvebu-uart.c
index 45b57c294d13..7e0a3e9fee15 100644
--- a/drivers/tty/serial/mvebu-uart.c
+++ b/drivers/tty/serial/mvebu-uart.c
@@ -90,6 +90,7 @@
 #define MVEBU_NR_UARTS		1
 
 #define MVEBU_UART_TYPE		"mvebu-uart"
+#define DRIVER_NAME		"mvebu_serial"
 
 static struct uart_port mvebu_uart_ports[MVEBU_NR_UARTS];
 
@@ -287,8 +288,8 @@ static int mvebu_uart_startup(struct uart_port *port)
 	udelay(1);
 	writel(CTRL_RX_INT, port->membase + UART_CTRL);
 
-	ret = request_irq(port->irq, mvebu_uart_isr, port->irqflags, "serial",
-			  port);
+	ret = request_irq(port->irq, mvebu_uart_isr, port->irqflags,
+			  DRIVER_NAME, port);
 	if (ret) {
 		dev_err(port->dev, "failed to request irq\n");
 		return ret;
@@ -538,7 +539,7 @@ console_initcall(mvebu_uart_console_init);
 
 static struct uart_driver mvebu_uart_driver = {
 	.owner			= THIS_MODULE,
-	.driver_name		= "mvebu_serial",
+	.driver_name		= DRIVER_NAME,
 	.dev_name		= "ttyMV",
 	.nr			= MVEBU_NR_UARTS,
 #ifdef CONFIG_SERIAL_MVEBU_CONSOLE
-- 
2.11.0

^ permalink raw reply related	[flat|nested] 29+ messages in thread

* [PATCH v2 04/16] serial: mvebu-uart: support probe of multiple ports
  2017-10-13  9:01 [PATCH v2 00/16] Support armada-37xx second UART port Miquel Raynal
                   ` (2 preceding siblings ...)
  2017-10-13  9:01 ` [PATCH v2 03/16] serial: mvebu-uart: use driver name when requesting an interrupt Miquel Raynal
@ 2017-10-13  9:01 ` Miquel Raynal
  2017-10-13  9:40   ` Gregory CLEMENT
  2017-10-13  9:01 ` [PATCH v2 05/16] serial: mvebu-uart: use a generic way to access the registers Miquel Raynal
                   ` (11 subsequent siblings)
  15 siblings, 1 reply; 29+ messages in thread
From: Miquel Raynal @ 2017-10-13  9:01 UTC (permalink / raw)
  To: linux-arm-kernel

From: Allen Yan <yanwei@marvell.com>

Until now, the mvebu-uart driver only supported probing a single UART
port. However, some platforms have multiple instances of this UART
controller, and therefore the driver should support multiple ports.

In order to achieve this, we make sure to assign port->line properly,
instead of hardcoding it to zero.

Signed-off-by: Allen Yan <yanwei@marvell.com>
Signed-off-by: Miquel Raynal <miquel.raynal@free-electrons.com>
---

Changes since v1: using multiple UART ports with this driver is not a
problem anymore if not using a device tree.

 drivers/tty/serial/mvebu-uart.c | 22 +++++++++++++++++++---
 1 file changed, 19 insertions(+), 3 deletions(-)

diff --git a/drivers/tty/serial/mvebu-uart.c b/drivers/tty/serial/mvebu-uart.c
index 7e0a3e9fee15..f3c7271db32b 100644
--- a/drivers/tty/serial/mvebu-uart.c
+++ b/drivers/tty/serial/mvebu-uart.c
@@ -547,20 +547,36 @@ static struct uart_driver mvebu_uart_driver = {
 #endif
 };
 
+/* Counter to keep track of each UART port id when not using CONFIG_OF */
+static int uart_num_counter;
+
 static int mvebu_uart_probe(struct platform_device *pdev)
 {
 	struct resource *reg = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 	struct resource *irq = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
 	struct uart_port *port;
 	struct mvebu_uart_data *data;
-	int ret;
+	int ret, id;
 
 	if (!reg || !irq) {
 		dev_err(&pdev->dev, "no registers/irq defined\n");
 		return -EINVAL;
 	}
 
-	port = &mvebu_uart_ports[0];
+	/* Assume that all UART ports have a DT alias or none has */
+	id = of_alias_get_id(pdev->dev.of_node, "serial");
+	if (!pdev->dev.of_node || id < 0)
+		pdev->id = uart_num_counter++;
+	else
+		pdev->id = id;
+
+	if (pdev->id >= MVEBU_NR_UARTS) {
+		dev_err(&pdev->dev, "cannot have more than %d UART ports\n",
+			MVEBU_NR_UARTS);
+		return -EINVAL;
+	}
+
+	port = &mvebu_uart_ports[pdev->id];
 
 	spin_lock_init(&port->lock);
 
@@ -572,7 +588,7 @@ static int mvebu_uart_probe(struct platform_device *pdev)
 	port->fifosize   = 32;
 	port->iotype     = UPIO_MEM32;
 	port->flags      = UPF_FIXED_PORT;
-	port->line       = 0; /* single port: force line number to  0 */
+	port->line       = pdev->id;
 
 	port->irq        = irq->start;
 	port->irqflags   = 0;
-- 
2.11.0

^ permalink raw reply related	[flat|nested] 29+ messages in thread

* [PATCH v2 05/16] serial: mvebu-uart: use a generic way to access the registers
  2017-10-13  9:01 [PATCH v2 00/16] Support armada-37xx second UART port Miquel Raynal
                   ` (3 preceding siblings ...)
  2017-10-13  9:01 ` [PATCH v2 04/16] serial: mvebu-uart: support probe of multiple ports Miquel Raynal
@ 2017-10-13  9:01 ` Miquel Raynal
  2017-10-13  9:01 ` [PATCH v2 06/16] serial: mvebu-uart: add soft reset at probe Miquel Raynal
                   ` (10 subsequent siblings)
  15 siblings, 0 replies; 29+ messages in thread
From: Miquel Raynal @ 2017-10-13  9:01 UTC (permalink / raw)
  To: linux-arm-kernel

There are two UART ports on Armada3700. The second UART is based on the
first one, plus additional features, but it has a different register
layout (some bit fields are also moved inside the registers).

Clearly separate register offsets and bit fields that differ between the
standard and the extended IP. Access them in a generic way. Rename the
defines with the "STD" prefix for future distinction with "EXT" defines.
Point to these defines in the main driver data structure.

The early console only uses the standard port (not extended).

Suggested-by: Wilson Ding <dingwei@marvell.com>
Signed-off-by: Miquel Raynal <miquel.raynal@free-electrons.com>
Reviewed-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
---
 drivers/tty/serial/mvebu-uart.c | 213 ++++++++++++++++++++++++++--------------
 1 file changed, 140 insertions(+), 73 deletions(-)

diff --git a/drivers/tty/serial/mvebu-uart.c b/drivers/tty/serial/mvebu-uart.c
index f3c7271db32b..900fe85796d6 100644
--- a/drivers/tty/serial/mvebu-uart.c
+++ b/drivers/tty/serial/mvebu-uart.c
@@ -38,46 +38,32 @@
 #include <linux/tty_flip.h>
 
 /* Register Map */
-#define UART_RBR		0x00
-#define  RBR_BRK_DET		BIT(15)
-#define  RBR_FRM_ERR_DET	BIT(14)
-#define  RBR_PAR_ERR_DET	BIT(13)
-#define  RBR_OVR_ERR_DET	BIT(12)
+#define UART_STD_RBR		0x00
 
-#define UART_TSH		0x04
+#define UART_STD_TSH		0x04
 
-#define UART_CTRL		0x08
+#define UART_STD_CTRL1		0x08
 #define  CTRL_SOFT_RST		BIT(31)
 #define  CTRL_TXFIFO_RST	BIT(15)
 #define  CTRL_RXFIFO_RST	BIT(14)
-#define  CTRL_ST_MIRR_EN	BIT(13)
-#define  CTRL_LPBK_EN		BIT(12)
 #define  CTRL_SND_BRK_SEQ	BIT(11)
-#define  CTRL_PAR_EN		BIT(10)
-#define  CTRL_TWO_STOP		BIT(9)
-#define  CTRL_TX_HFL_INT	BIT(8)
-#define  CTRL_RX_HFL_INT	BIT(7)
-#define  CTRL_TX_EMP_INT	BIT(6)
-#define  CTRL_TX_RDY_INT	BIT(5)
-#define  CTRL_RX_RDY_INT	BIT(4)
 #define  CTRL_BRK_DET_INT	BIT(3)
 #define  CTRL_FRM_ERR_INT	BIT(2)
 #define  CTRL_PAR_ERR_INT	BIT(1)
 #define  CTRL_OVR_ERR_INT	BIT(0)
-#define  CTRL_RX_INT			(CTRL_RX_RDY_INT | CTRL_BRK_DET_INT |\
-	CTRL_FRM_ERR_INT | CTRL_PAR_ERR_INT | CTRL_OVR_ERR_INT)
+#define  CTRL_BRK_INT		(CTRL_BRK_DET_INT | CTRL_FRM_ERR_INT | \
+				CTRL_PAR_ERR_INT | CTRL_OVR_ERR_INT)
 
-#define UART_STAT		0x0c
+#define UART_STD_CTRL2		UART_STD_CTRL1
+#define  CTRL_STD_TX_RDY_INT	BIT(5)
+#define  CTRL_STD_RX_RDY_INT	BIT(4)
+
+#define UART_STAT		0x0C
 #define  STAT_TX_FIFO_EMP	BIT(13)
-#define  STAT_RX_FIFO_EMP	BIT(12)
 #define  STAT_TX_FIFO_FUL	BIT(11)
-#define  STAT_TX_FIFO_HFL	BIT(10)
-#define  STAT_RX_TOGL		BIT(9)
-#define  STAT_RX_FIFO_FUL	BIT(8)
-#define  STAT_RX_FIFO_HFL	BIT(7)
 #define  STAT_TX_EMP		BIT(6)
-#define  STAT_TX_RDY		BIT(5)
-#define  STAT_RX_RDY		BIT(4)
+#define  STAT_STD_TX_RDY	BIT(5)
+#define  STAT_STD_RX_RDY	BIT(4)
 #define  STAT_BRK_DET		BIT(3)
 #define  STAT_FRM_ERR		BIT(2)
 #define  STAT_PAR_ERR		BIT(1)
@@ -92,13 +78,55 @@
 #define MVEBU_UART_TYPE		"mvebu-uart"
 #define DRIVER_NAME		"mvebu_serial"
 
-static struct uart_port mvebu_uart_ports[MVEBU_NR_UARTS];
+/* Register offsets, different depending on the UART */
+struct uart_regs_layout {
+	unsigned int rbr;
+	unsigned int tsh;
+	unsigned int ctrl;
+	unsigned int intr;
+};
+
+/* Diverging flags */
+struct uart_flags {
+	unsigned int ctrl_tx_rdy_int;
+	unsigned int ctrl_rx_rdy_int;
+	unsigned int stat_tx_rdy;
+	unsigned int stat_rx_rdy;
+};
+
+/* Driver data, a structure for each UART port */
+struct mvebu_uart_driver_data {
+	bool is_ext;
+	struct uart_regs_layout regs;
+	struct uart_flags flags;
+};
 
-struct mvebu_uart_data {
+/* MVEBU UART driver structure */
+struct mvebu_uart {
 	struct uart_port *port;
-	struct clk       *clk;
+	struct clk *clk;
+	struct mvebu_uart_driver_data *data;
 };
 
+static struct mvebu_uart *to_mvuart(struct uart_port *port)
+{
+	return (struct mvebu_uart *)port->private_data;
+}
+
+#define IS_EXTENDED(port) (to_mvuart(port)->data->is_ext)
+
+#define UART_RBR(port) (to_mvuart(port)->data->regs.rbr)
+#define UART_TSH(port) (to_mvuart(port)->data->regs.tsh)
+#define UART_CTRL(port) (to_mvuart(port)->data->regs.ctrl)
+#define UART_INTR(port) (to_mvuart(port)->data->regs.intr)
+
+#define CTRL_TX_RDY_INT(port) (to_mvuart(port)->data->flags.ctrl_tx_rdy_int)
+#define CTRL_RX_RDY_INT(port) (to_mvuart(port)->data->flags.ctrl_rx_rdy_int)
+#define STAT_TX_RDY(port) (to_mvuart(port)->data->flags.stat_tx_rdy)
+#define STAT_RX_RDY(port) (to_mvuart(port)->data->flags.stat_rx_rdy)
+
+static struct uart_port mvebu_uart_ports[MVEBU_NR_UARTS];
+
 /* Core UART Driver Operations */
 static unsigned int mvebu_uart_tx_empty(struct uart_port *port)
 {
@@ -128,26 +156,31 @@ static void mvebu_uart_set_mctrl(struct uart_port *port,
 
 static void mvebu_uart_stop_tx(struct uart_port *port)
 {
-	unsigned int ctl = readl(port->membase + UART_CTRL);
+	unsigned int ctl = readl(port->membase + UART_INTR(port));
 
-	ctl &= ~CTRL_TX_RDY_INT;
-	writel(ctl, port->membase + UART_CTRL);
+	ctl &= ~CTRL_TX_RDY_INT(port);
+	writel(ctl, port->membase + UART_INTR(port));
 }
 
 static void mvebu_uart_start_tx(struct uart_port *port)
 {
-	unsigned int ctl = readl(port->membase + UART_CTRL);
+	unsigned int ctl = readl(port->membase + UART_INTR(port));
 
-	ctl |= CTRL_TX_RDY_INT;
-	writel(ctl, port->membase + UART_CTRL);
+	ctl |= CTRL_TX_RDY_INT(port);
+	writel(ctl, port->membase + UART_INTR(port));
 }
 
 static void mvebu_uart_stop_rx(struct uart_port *port)
 {
-	unsigned int ctl = readl(port->membase + UART_CTRL);
+	unsigned int ctl;
 
-	ctl &= ~CTRL_RX_INT;
-	writel(ctl, port->membase + UART_CTRL);
+	ctl = readl(port->membase + UART_CTRL(port));
+	ctl &= ~CTRL_BRK_INT;
+	writel(ctl, port->membase + UART_CTRL(port));
+
+	ctl = readl(port->membase + UART_INTR(port));
+	ctl &= ~CTRL_RX_RDY_INT(port);
+	writel(ctl, port->membase + UART_INTR(port));
 }
 
 static void mvebu_uart_break_ctl(struct uart_port *port, int brk)
@@ -156,12 +189,12 @@ static void mvebu_uart_break_ctl(struct uart_port *port, int brk)
 	unsigned long flags;
 
 	spin_lock_irqsave(&port->lock, flags);
-	ctl = readl(port->membase + UART_CTRL);
+	ctl = readl(port->membase + UART_CTRL(port));
 	if (brk == -1)
 		ctl |= CTRL_SND_BRK_SEQ;
 	else
 		ctl &= ~CTRL_SND_BRK_SEQ;
-	writel(ctl, port->membase + UART_CTRL);
+	writel(ctl, port->membase + UART_CTRL(port));
 	spin_unlock_irqrestore(&port->lock, flags);
 }
 
@@ -172,8 +205,8 @@ static void mvebu_uart_rx_chars(struct uart_port *port, unsigned int status)
 	char flag = 0;
 
 	do {
-		if (status & STAT_RX_RDY) {
-			ch = readl(port->membase + UART_RBR);
+		if (status & STAT_RX_RDY(port)) {
+			ch = readl(port->membase + UART_RBR(port));
 			ch &= 0xff;
 			flag = TTY_NORMAL;
 			port->icount.rx++;
@@ -199,7 +232,7 @@ static void mvebu_uart_rx_chars(struct uart_port *port, unsigned int status)
 			goto ignore_char;
 
 		if (status & port->ignore_status_mask & STAT_PAR_ERR)
-			status &= ~STAT_RX_RDY;
+			status &= ~STAT_RX_RDY(port);
 
 		status &= port->read_status_mask;
 
@@ -208,7 +241,7 @@ static void mvebu_uart_rx_chars(struct uart_port *port, unsigned int status)
 
 		status &= ~port->ignore_status_mask;
 
-		if (status & STAT_RX_RDY)
+		if (status & STAT_RX_RDY(port))
 			tty_insert_flip_char(tport, ch, flag);
 
 		if (status & STAT_BRK_DET)
@@ -222,7 +255,7 @@ static void mvebu_uart_rx_chars(struct uart_port *port, unsigned int status)
 
 ignore_char:
 		status = readl(port->membase + UART_STAT);
-	} while (status & (STAT_RX_RDY | STAT_BRK_DET));
+	} while (status & (STAT_RX_RDY(port) | STAT_BRK_DET));
 
 	tty_flip_buffer_push(tport);
 }
@@ -234,7 +267,7 @@ static void mvebu_uart_tx_chars(struct uart_port *port, unsigned int status)
 	unsigned int st;
 
 	if (port->x_char) {
-		writel(port->x_char, port->membase + UART_TSH);
+		writel(port->x_char, port->membase + UART_TSH(port));
 		port->icount.tx++;
 		port->x_char = 0;
 		return;
@@ -246,7 +279,7 @@ static void mvebu_uart_tx_chars(struct uart_port *port, unsigned int status)
 	}
 
 	for (count = 0; count < port->fifosize; count++) {
-		writel(xmit->buf[xmit->tail], port->membase + UART_TSH);
+		writel(xmit->buf[xmit->tail], port->membase + UART_TSH(port));
 		xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
 		port->icount.tx++;
 
@@ -270,10 +303,11 @@ static irqreturn_t mvebu_uart_isr(int irq, void *dev_id)
 	struct uart_port *port = (struct uart_port *)dev_id;
 	unsigned int st = readl(port->membase + UART_STAT);
 
-	if (st & (STAT_RX_RDY | STAT_OVR_ERR | STAT_FRM_ERR | STAT_BRK_DET))
+	if (st & (STAT_RX_RDY(port) | STAT_OVR_ERR | STAT_FRM_ERR |
+			STAT_BRK_DET))
 		mvebu_uart_rx_chars(port, st);
 
-	if (st & STAT_TX_RDY)
+	if (st & STAT_TX_RDY(port))
 		mvebu_uart_tx_chars(port, st);
 
 	return IRQ_HANDLED;
@@ -281,12 +315,17 @@ static irqreturn_t mvebu_uart_isr(int irq, void *dev_id)
 
 static int mvebu_uart_startup(struct uart_port *port)
 {
+	unsigned int ctl;
 	int ret;
 
 	writel(CTRL_TXFIFO_RST | CTRL_RXFIFO_RST,
-	       port->membase + UART_CTRL);
+	       port->membase + UART_CTRL(port));
 	udelay(1);
-	writel(CTRL_RX_INT, port->membase + UART_CTRL);
+	writel(CTRL_BRK_INT, port->membase + UART_CTRL(port));
+
+	ctl = readl(port->membase + UART_INTR(port));
+	ctl |= CTRL_RX_RDY_INT(port);
+	writel(ctl, port->membase + UART_INTR(port));
 
 	ret = request_irq(port->irq, mvebu_uart_isr, port->irqflags,
 			  DRIVER_NAME, port);
@@ -300,7 +339,7 @@ static int mvebu_uart_startup(struct uart_port *port)
 
 static void mvebu_uart_shutdown(struct uart_port *port)
 {
-	writel(0, port->membase + UART_CTRL);
+	writel(0, port->membase + UART_INTR(port));
 
 	free_irq(port->irq, port);
 }
@@ -314,8 +353,8 @@ static void mvebu_uart_set_termios(struct uart_port *port,
 
 	spin_lock_irqsave(&port->lock, flags);
 
-	port->read_status_mask = STAT_RX_RDY | STAT_OVR_ERR |
-		STAT_TX_RDY | STAT_TX_FIFO_FUL;
+	port->read_status_mask = STAT_RX_RDY(port) | STAT_OVR_ERR |
+		STAT_TX_RDY(port) | STAT_TX_FIFO_FUL;
 
 	if (termios->c_iflag & INPCK)
 		port->read_status_mask |= STAT_FRM_ERR | STAT_PAR_ERR;
@@ -326,7 +365,7 @@ static void mvebu_uart_set_termios(struct uart_port *port,
 			STAT_FRM_ERR | STAT_PAR_ERR | STAT_OVR_ERR;
 
 	if ((termios->c_cflag & CREAD) == 0)
-		port->ignore_status_mask |= STAT_RX_RDY | STAT_BRK_ERR;
+		port->ignore_status_mask |= STAT_RX_RDY(port) | STAT_BRK_ERR;
 
 	if (old)
 		tty_termios_copy_hw(termios, old);
@@ -357,10 +396,10 @@ static int mvebu_uart_get_poll_char(struct uart_port *port)
 {
 	unsigned int st = readl(port->membase + UART_STAT);
 
-	if (!(st & STAT_RX_RDY))
+	if (!(st & STAT_RX_RDY(port)))
 		return NO_POLL_CHAR;
 
-	return readl(port->membase + UART_RBR);
+	return readl(port->membase + UART_RBR(port));
 }
 
 static void mvebu_uart_put_poll_char(struct uart_port *port, unsigned char c)
@@ -376,7 +415,7 @@ static void mvebu_uart_put_poll_char(struct uart_port *port, unsigned char c)
 		udelay(1);
 	}
 
-	writel(c, port->membase + UART_TSH);
+	writel(c, port->membase + UART_TSH(port));
 }
 #endif
 
@@ -414,7 +453,8 @@ static void mvebu_uart_putc(struct uart_port *port, int c)
 			break;
 	}
 
-	writel(c, port->membase + UART_TSH);
+	/* At early stage, DT is not parsed yet, only use UART0 */
+	writel(c, port->membase + UART_STD_TSH);
 
 	for (;;) {
 		st = readl(port->membase + UART_STAT);
@@ -459,7 +499,7 @@ static void wait_for_xmitr(struct uart_port *port)
 static void mvebu_uart_console_putchar(struct uart_port *port, int ch)
 {
 	wait_for_xmitr(port);
-	writel(ch, port->membase + UART_TSH);
+	writel(ch, port->membase + UART_TSH(port));
 }
 
 static void mvebu_uart_console_write(struct console *co, const char *s,
@@ -467,7 +507,7 @@ static void mvebu_uart_console_write(struct console *co, const char *s,
 {
 	struct uart_port *port = &mvebu_uart_ports[co->index];
 	unsigned long flags;
-	unsigned int ier;
+	unsigned int ier, intr, ctl;
 	int locked = 1;
 
 	if (oops_in_progress)
@@ -475,16 +515,23 @@ static void mvebu_uart_console_write(struct console *co, const char *s,
 	else
 		spin_lock_irqsave(&port->lock, flags);
 
-	ier = readl(port->membase + UART_CTRL) &
-		(CTRL_RX_INT | CTRL_TX_RDY_INT);
-	writel(0, port->membase + UART_CTRL);
+	ier = readl(port->membase + UART_CTRL(port)) & CTRL_BRK_INT;
+	intr = readl(port->membase + UART_INTR(port)) &
+		(CTRL_RX_RDY_INT(port) | CTRL_TX_RDY_INT(port));
+	writel(0, port->membase + UART_CTRL(port));
+	writel(0, port->membase + UART_INTR(port));
 
 	uart_console_write(port, s, count, mvebu_uart_console_putchar);
 
 	wait_for_xmitr(port);
 
 	if (ier)
-		writel(ier, port->membase + UART_CTRL);
+		writel(ier, port->membase + UART_CTRL(port));
+
+	if (intr) {
+		ctl = intr | readl(port->membase + UART_INTR(port));
+		writel(ctl, port->membase + UART_INTR(port));
+	}
 
 	if (locked)
 		spin_unlock_irqrestore(&port->lock, flags);
@@ -547,6 +594,8 @@ static struct uart_driver mvebu_uart_driver = {
 #endif
 };
 
+static const struct of_device_id mvebu_uart_of_match[];
+
 /* Counter to keep track of each UART port id when not using CONFIG_OF */
 static int uart_num_counter;
 
@@ -554,8 +603,10 @@ static int mvebu_uart_probe(struct platform_device *pdev)
 {
 	struct resource *reg = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 	struct resource *irq = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
+	const struct of_device_id *match = of_match_device(mvebu_uart_of_match,
+							   &pdev->dev);
 	struct uart_port *port;
-	struct mvebu_uart_data *data;
+	struct mvebu_uart *mvuart;
 	int ret, id;
 
 	if (!reg || !irq) {
@@ -598,15 +649,16 @@ static int mvebu_uart_probe(struct platform_device *pdev)
 	if (IS_ERR(port->membase))
 		return -PTR_ERR(port->membase);
 
-	data = devm_kzalloc(&pdev->dev, sizeof(struct mvebu_uart_data),
-			    GFP_KERNEL);
-	if (!data)
+	mvuart = devm_kzalloc(&pdev->dev, sizeof(struct mvebu_uart),
+			      GFP_KERNEL);
+	if (!mvuart)
 		return -ENOMEM;
 
-	data->port = port;
+	mvuart->data = (struct mvebu_uart_driver_data *)match->data;
+	mvuart->port = port;
 
-	port->private_data = data;
-	platform_set_drvdata(pdev, data);
+	port->private_data = mvuart;
+	platform_set_drvdata(pdev, mvuart);
 
 	ret = uart_add_one_port(&mvebu_uart_driver, port);
 	if (ret)
@@ -614,9 +666,24 @@ static int mvebu_uart_probe(struct platform_device *pdev)
 	return 0;
 }
 
+static struct mvebu_uart_driver_data uart_std_driver_data = {
+	.is_ext = false,
+	.regs.rbr = UART_STD_RBR,
+	.regs.tsh = UART_STD_TSH,
+	.regs.ctrl = UART_STD_CTRL1,
+	.regs.intr = UART_STD_CTRL2,
+	.flags.ctrl_tx_rdy_int = CTRL_STD_TX_RDY_INT,
+	.flags.ctrl_rx_rdy_int = CTRL_STD_RX_RDY_INT,
+	.flags.stat_tx_rdy = STAT_STD_TX_RDY,
+	.flags.stat_rx_rdy = STAT_STD_RX_RDY,
+};
+
 /* Match table for of_platform binding */
 static const struct of_device_id mvebu_uart_of_match[] = {
-	{ .compatible = "marvell,armada-3700-uart", },
+	{
+		.compatible = "marvell,armada-3700-uart",
+		.data = (void *)&uart_std_driver_data,
+	},
 	{}
 };
 
-- 
2.11.0

^ permalink raw reply related	[flat|nested] 29+ messages in thread

* [PATCH v2 06/16] serial: mvebu-uart: add soft reset at probe
  2017-10-13  9:01 [PATCH v2 00/16] Support armada-37xx second UART port Miquel Raynal
                   ` (4 preceding siblings ...)
  2017-10-13  9:01 ` [PATCH v2 05/16] serial: mvebu-uart: use a generic way to access the registers Miquel Raynal
@ 2017-10-13  9:01 ` Miquel Raynal
  2017-10-13  9:01 ` [PATCH v2 07/16] serial: mvebu-uart: add function to change baudrate Miquel Raynal
                   ` (9 subsequent siblings)
  15 siblings, 0 replies; 29+ messages in thread
From: Miquel Raynal @ 2017-10-13  9:01 UTC (permalink / raw)
  To: linux-arm-kernel

From: Allen Yan <yanwei@marvell.com>

The existing UART driver relies on the bootloader to initialize the
port(s). However, the secondary uart port may not be initialized
properly in early boot stage. This patch adds the UART soft reset when
probing, for all ports.

Signed-off-by: Allen Yan <yanwei@marvell.com>
Signed-off-by: Miquel Raynal <miquel.raynal@free-electrons.com>
Reviewed-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
---
 drivers/tty/serial/mvebu-uart.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/drivers/tty/serial/mvebu-uart.c b/drivers/tty/serial/mvebu-uart.c
index 900fe85796d6..e233f464d55a 100644
--- a/drivers/tty/serial/mvebu-uart.c
+++ b/drivers/tty/serial/mvebu-uart.c
@@ -660,6 +660,11 @@ static int mvebu_uart_probe(struct platform_device *pdev)
 	port->private_data = mvuart;
 	platform_set_drvdata(pdev, mvuart);
 
+	/* UART Soft Reset*/
+	writel(CTRL_SOFT_RST, port->membase + UART_CTRL(port));
+	udelay(1);
+	writel(0, port->membase + UART_CTRL(port));
+
 	ret = uart_add_one_port(&mvebu_uart_driver, port);
 	if (ret)
 		return ret;
-- 
2.11.0

^ permalink raw reply related	[flat|nested] 29+ messages in thread

* [PATCH v2 07/16] serial: mvebu-uart: add function to change baudrate
  2017-10-13  9:01 [PATCH v2 00/16] Support armada-37xx second UART port Miquel Raynal
                   ` (5 preceding siblings ...)
  2017-10-13  9:01 ` [PATCH v2 06/16] serial: mvebu-uart: add soft reset at probe Miquel Raynal
@ 2017-10-13  9:01 ` Miquel Raynal
  2017-10-13  9:01 ` [PATCH v2 08/16] serial: mvebu-uart: clear state register before IRQ request Miquel Raynal
                   ` (8 subsequent siblings)
  15 siblings, 0 replies; 29+ messages in thread
From: Miquel Raynal @ 2017-10-13  9:01 UTC (permalink / raw)
  To: linux-arm-kernel

From: Allen Yan <yanwei@marvell.com>

Until now, the first UART port baudrate was set by the bootloader.

Add a function allowing to change the baudrate. Changes may be done
from userspace but also at probe time by the kernel. Use the simplest
method: baudrate divisor.

Works for all UART ports until 230400 baud. To achieve higher baudrates,
software should implement the fractional divisor feature that allows
more accuracy for higher rates.

Signed-off-by: Allen Yan <yanwei@marvell.com>
[<miquel.raynal@free-electrons.com>: changed termios handling]
Signed-off-by: Miquel Raynal <miquel.raynal@free-electrons.com>
Reviewed-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
---
 drivers/tty/serial/mvebu-uart.c | 69 ++++++++++++++++++++++++++++++++++++++---
 1 file changed, 65 insertions(+), 4 deletions(-)

diff --git a/drivers/tty/serial/mvebu-uart.c b/drivers/tty/serial/mvebu-uart.c
index e233f464d55a..5767196ec0a9 100644
--- a/drivers/tty/serial/mvebu-uart.c
+++ b/drivers/tty/serial/mvebu-uart.c
@@ -72,6 +72,7 @@
 				 | STAT_PAR_ERR | STAT_OVR_ERR)
 
 #define UART_BRDV		0x10
+#define  BRDV_BAUD_MASK         0x3FF
 
 #define MVEBU_NR_UARTS		1
 
@@ -344,6 +345,31 @@ static void mvebu_uart_shutdown(struct uart_port *port)
 	free_irq(port->irq, port);
 }
 
+static int mvebu_uart_baud_rate_set(struct uart_port *port, unsigned int baud)
+{
+	struct mvebu_uart *mvuart = to_mvuart(port);
+	unsigned int baud_rate_div;
+	u32 brdv;
+
+	if (IS_ERR(mvuart->clk))
+		return -PTR_ERR(mvuart->clk);
+
+	/*
+	 * The UART clock is divided by the value of the divisor to generate
+	 * UCLK_OUT clock, which is 16 times faster than the baudrate.
+	 * This prescaler can achieve all standard baudrates until 230400.
+	 * Higher baudrates could be achieved for the extended UART by using the
+	 * programmable oversampling stack (also called fractional divisor).
+	 */
+	baud_rate_div = DIV_ROUND_UP(port->uartclk, baud * 16);
+	brdv = readl(port->membase + UART_BRDV);
+	brdv &= ~BRDV_BAUD_MASK;
+	brdv |= baud_rate_div;
+	writel(brdv, port->membase + UART_BRDV);
+
+	return 0;
+}
+
 static void mvebu_uart_set_termios(struct uart_port *port,
 				   struct ktermios *termios,
 				   struct ktermios *old)
@@ -367,11 +393,30 @@ static void mvebu_uart_set_termios(struct uart_port *port,
 	if ((termios->c_cflag & CREAD) == 0)
 		port->ignore_status_mask |= STAT_RX_RDY(port) | STAT_BRK_ERR;
 
-	if (old)
-		tty_termios_copy_hw(termios, old);
+	/*
+	 * Maximum achievable frequency with simple baudrate divisor is 230400.
+	 * Since the error per bit frame would be of more than 15%, achieving
+	 * higher frequencies would require to implement the fractional divisor
+	 * feature.
+	 */
+	baud = uart_get_baud_rate(port, termios, old, 0, 230400);
+	if (mvebu_uart_baud_rate_set(port, baud)) {
+		/* No clock available, baudrate cannot be changed */
+		if (old)
+			baud = uart_get_baud_rate(port, old, NULL, 0, 230400);
+	} else {
+		tty_termios_encode_baud_rate(termios, baud, baud);
+		uart_update_timeout(port, termios->c_cflag, baud);
+	}
 
-	baud = uart_get_baud_rate(port, termios, old, 0, 460800);
-	uart_update_timeout(port, termios->c_cflag, baud);
+	/* Only the following flag changes are supported */
+	if (old) {
+		termios->c_iflag &= INPCK | IGNPAR;
+		termios->c_iflag |= old->c_iflag & ~(INPCK | IGNPAR);
+		termios->c_cflag &= CREAD | CBAUD;
+		termios->c_cflag |= old->c_cflag & ~(CREAD | CBAUD);
+		termios->c_lflag = old->c_lflag;
+	}
 
 	spin_unlock_irqrestore(&port->lock, flags);
 }
@@ -654,12 +699,28 @@ static int mvebu_uart_probe(struct platform_device *pdev)
 	if (!mvuart)
 		return -ENOMEM;
 
+	/* Get controller data depending on the compatible string */
 	mvuart->data = (struct mvebu_uart_driver_data *)match->data;
 	mvuart->port = port;
 
 	port->private_data = mvuart;
 	platform_set_drvdata(pdev, mvuart);
 
+	/* Get fixed clock frequency */
+	mvuart->clk = devm_clk_get(&pdev->dev, NULL);
+	if (IS_ERR(mvuart->clk)) {
+		if (PTR_ERR(mvuart->clk) == -EPROBE_DEFER)
+			return PTR_ERR(mvuart->clk);
+
+		if (IS_EXTENDED(port)) {
+			dev_err(&pdev->dev, "unable to get UART clock\n");
+			return PTR_ERR(mvuart->clk);
+		}
+	} else {
+		if (!clk_prepare_enable(mvuart->clk))
+			port->uartclk = clk_get_rate(mvuart->clk);
+	}
+
 	/* UART Soft Reset*/
 	writel(CTRL_SOFT_RST, port->membase + UART_CTRL(port));
 	udelay(1);
-- 
2.11.0

^ permalink raw reply related	[flat|nested] 29+ messages in thread

* [PATCH v2 08/16] serial: mvebu-uart: clear state register before IRQ request
  2017-10-13  9:01 [PATCH v2 00/16] Support armada-37xx second UART port Miquel Raynal
                   ` (6 preceding siblings ...)
  2017-10-13  9:01 ` [PATCH v2 07/16] serial: mvebu-uart: add function to change baudrate Miquel Raynal
@ 2017-10-13  9:01 ` Miquel Raynal
  2017-10-13  9:01 ` [PATCH v2 09/16] serial: mvebu-uart: add TX interrupt trigger for pulse interrupts Miquel Raynal
                   ` (7 subsequent siblings)
  15 siblings, 0 replies; 29+ messages in thread
From: Miquel Raynal @ 2017-10-13  9:01 UTC (permalink / raw)
  To: linux-arm-kernel

From: Allen Yan <yanwei@marvell.com>

When receiving data on RX pin before ->uart_startup() is called, some
error bits in the state register could be set up (like BRK_DET).

This is harmless when using only the standard UART (error bits are
read-only), but may procude an endless loop once in the extended UART
RX interrupt handler (error bits must be cleared).

Clear the status register in ->uart_startup() to avoid this situation.

Signed-off-by: Allen Yan <yanwei@marvell.com>
Signed-off-by: Miquel Raynal <miquel.raynal@free-electrons.com>
Reviewed-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
---
 drivers/tty/serial/mvebu-uart.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/drivers/tty/serial/mvebu-uart.c b/drivers/tty/serial/mvebu-uart.c
index 5767196ec0a9..6bd0c40008bb 100644
--- a/drivers/tty/serial/mvebu-uart.c
+++ b/drivers/tty/serial/mvebu-uart.c
@@ -322,6 +322,12 @@ static int mvebu_uart_startup(struct uart_port *port)
 	writel(CTRL_TXFIFO_RST | CTRL_RXFIFO_RST,
 	       port->membase + UART_CTRL(port));
 	udelay(1);
+
+	/* Clear the error bits of state register before IRQ request */
+	ret = readl(port->membase + UART_STAT);
+	ret |= STAT_BRK_ERR;
+	writel(ret, port->membase + UART_STAT);
+
 	writel(CTRL_BRK_INT, port->membase + UART_CTRL(port));
 
 	ctl = readl(port->membase + UART_INTR(port));
-- 
2.11.0

^ permalink raw reply related	[flat|nested] 29+ messages in thread

* [PATCH v2 09/16] serial: mvebu-uart: add TX interrupt trigger for pulse interrupts
  2017-10-13  9:01 [PATCH v2 00/16] Support armada-37xx second UART port Miquel Raynal
                   ` (7 preceding siblings ...)
  2017-10-13  9:01 ` [PATCH v2 08/16] serial: mvebu-uart: clear state register before IRQ request Miquel Raynal
@ 2017-10-13  9:01 ` Miquel Raynal
  2017-10-13  9:01 ` [PATCH v2 10/16] serial: mvebu-uart: dissociate RX and TX interrupts Miquel Raynal
                   ` (6 subsequent siblings)
  15 siblings, 0 replies; 29+ messages in thread
From: Miquel Raynal @ 2017-10-13  9:01 UTC (permalink / raw)
  To: linux-arm-kernel

From: Allen Yan <yanwei@marvell.com>

Pulse interrupts (extended UART only) needs a change of state to trigger
the TX interrupt. In addition to enabling the TX_READY_INT_EN flag,
produce a FIFO state change from 'empty' to 'not full'. For this, write
only one data byte in TX start, making the TX FIFO not empty, and wait
for the TX interrupt to continue the transfer.

Signed-off-by: Allen Yan <yanwei@marvell.com>
Signed-off-by: Miquel Raynal <miquel.raynal@free-electrons.com>
Reviewed-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
---
 drivers/tty/serial/mvebu-uart.c | 10 +++++++++-
 1 file changed, 9 insertions(+), 1 deletion(-)

diff --git a/drivers/tty/serial/mvebu-uart.c b/drivers/tty/serial/mvebu-uart.c
index 6bd0c40008bb..e52248ec2689 100644
--- a/drivers/tty/serial/mvebu-uart.c
+++ b/drivers/tty/serial/mvebu-uart.c
@@ -165,8 +165,16 @@ static void mvebu_uart_stop_tx(struct uart_port *port)
 
 static void mvebu_uart_start_tx(struct uart_port *port)
 {
-	unsigned int ctl = readl(port->membase + UART_INTR(port));
+	unsigned int ctl;
+	struct circ_buf *xmit = &port->state->xmit;
 
+	if (IS_EXTENDED(port) && !uart_circ_empty(xmit)) {
+		writel(xmit->buf[xmit->tail], port->membase + UART_TSH(port));
+		xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
+		port->icount.tx++;
+	}
+
+	ctl = readl(port->membase + UART_INTR(port));
 	ctl |= CTRL_TX_RDY_INT(port);
 	writel(ctl, port->membase + UART_INTR(port));
 }
-- 
2.11.0

^ permalink raw reply related	[flat|nested] 29+ messages in thread

* [PATCH v2 10/16] serial: mvebu-uart: dissociate RX and TX interrupts
  2017-10-13  9:01 [PATCH v2 00/16] Support armada-37xx second UART port Miquel Raynal
                   ` (8 preceding siblings ...)
  2017-10-13  9:01 ` [PATCH v2 09/16] serial: mvebu-uart: add TX interrupt trigger for pulse interrupts Miquel Raynal
@ 2017-10-13  9:01 ` Miquel Raynal
  2017-10-13  9:01 ` [PATCH v2 11/16] serial: mvebu-uart: augment the maximum number of ports Miquel Raynal
                   ` (5 subsequent siblings)
  15 siblings, 0 replies; 29+ messages in thread
From: Miquel Raynal @ 2017-10-13  9:01 UTC (permalink / raw)
  To: linux-arm-kernel

While the standard UART port can use a single IRQ that 'sums' both RX
and TX interrupts, the extended port cannot and has to use two different
ISR, one for each direction. The standard port also has the hability
to use two separate interrupts (one for each direction).

The logic is then: either there is only one unnamed interrupt on the
standard port and this interrupt must be used for both directions
(this is legacy bindings); or all the interrupts must be described and
named 'uart-sum' (if available), 'uart-rx', 'uart-tx' and two separate
handlers for each direction will be used.

Suggested-by: Allen Yan <yanwei@marvell.com>
Signed-off-by: Miquel Raynal <miquel.raynal@free-electrons.com>
---

Changes since v1: free IRQ with devm_*().

 drivers/tty/serial/mvebu-uart.c | 131 ++++++++++++++++++++++++++++++++++++----
 1 file changed, 119 insertions(+), 12 deletions(-)

diff --git a/drivers/tty/serial/mvebu-uart.c b/drivers/tty/serial/mvebu-uart.c
index e52248ec2689..d0e749f6f052 100644
--- a/drivers/tty/serial/mvebu-uart.c
+++ b/drivers/tty/serial/mvebu-uart.c
@@ -79,7 +79,16 @@
 #define MVEBU_UART_TYPE		"mvebu-uart"
 #define DRIVER_NAME		"mvebu_serial"
 
-/* Register offsets, different depending on the UART */
+enum {
+	/* Either there is only one summed IRQ... */
+	UART_IRQ_SUM = 0,
+	/* ...or there are two separate IRQ for RX and TX */
+	UART_RX_IRQ = 0,
+	UART_TX_IRQ,
+	UART_IRQ_COUNT
+};
+
+/* Diverging register offsets */
 struct uart_regs_layout {
 	unsigned int rbr;
 	unsigned int tsh;
@@ -106,6 +115,8 @@ struct mvebu_uart_driver_data {
 struct mvebu_uart {
 	struct uart_port *port;
 	struct clk *clk;
+	int irq[UART_IRQ_COUNT];
+	unsigned char __iomem *nb;
 	struct mvebu_uart_driver_data *data;
 };
 
@@ -313,9 +324,32 @@ static irqreturn_t mvebu_uart_isr(int irq, void *dev_id)
 	unsigned int st = readl(port->membase + UART_STAT);
 
 	if (st & (STAT_RX_RDY(port) | STAT_OVR_ERR | STAT_FRM_ERR |
+		  STAT_BRK_DET))
+		mvebu_uart_rx_chars(port, st);
+
+	if (st & STAT_TX_RDY(port))
+		mvebu_uart_tx_chars(port, st);
+
+	return IRQ_HANDLED;
+}
+
+static irqreturn_t mvebu_uart_rx_isr(int irq, void *dev_id)
+{
+	struct uart_port *port = (struct uart_port *)dev_id;
+	unsigned int st = readl(port->membase + UART_STAT);
+
+	if (st & (STAT_RX_RDY(port) | STAT_OVR_ERR | STAT_FRM_ERR |
 			STAT_BRK_DET))
 		mvebu_uart_rx_chars(port, st);
 
+	return IRQ_HANDLED;
+}
+
+static irqreturn_t mvebu_uart_tx_isr(int irq, void *dev_id)
+{
+	struct uart_port *port = (struct uart_port *)dev_id;
+	unsigned int st = readl(port->membase + UART_STAT);
+
 	if (st & STAT_TX_RDY(port))
 		mvebu_uart_tx_chars(port, st);
 
@@ -324,6 +358,7 @@ static irqreturn_t mvebu_uart_isr(int irq, void *dev_id)
 
 static int mvebu_uart_startup(struct uart_port *port)
 {
+	struct mvebu_uart *mvuart = to_mvuart(port);
 	unsigned int ctl;
 	int ret;
 
@@ -342,11 +377,38 @@ static int mvebu_uart_startup(struct uart_port *port)
 	ctl |= CTRL_RX_RDY_INT(port);
 	writel(ctl, port->membase + UART_INTR(port));
 
-	ret = request_irq(port->irq, mvebu_uart_isr, port->irqflags,
-			  DRIVER_NAME, port);
-	if (ret) {
-		dev_err(port->dev, "failed to request irq\n");
-		return ret;
+	if (!mvuart->irq[UART_TX_IRQ]) {
+		/* Old bindings with just one interrupt (UART0 only) */
+		ret = devm_request_irq(port->dev, mvuart->irq[UART_IRQ_SUM],
+				       mvebu_uart_isr, port->irqflags,
+				       dev_name(port->dev), port);
+		if (ret) {
+			dev_err(port->dev, "unable to request IRQ %d\n",
+				mvuart->irq[UART_IRQ_SUM]);
+			return ret;
+		}
+	} else {
+		/* New bindings with an IRQ for RX and TX (both UART) */
+		ret = devm_request_irq(port->dev, mvuart->irq[UART_RX_IRQ],
+				       mvebu_uart_rx_isr, port->irqflags,
+				       dev_name(port->dev), port);
+		if (ret) {
+			dev_err(port->dev, "unable to request IRQ %d\n",
+				mvuart->irq[UART_RX_IRQ]);
+			return ret;
+		}
+
+		ret = devm_request_irq(port->dev, mvuart->irq[UART_TX_IRQ],
+				       mvebu_uart_tx_isr, port->irqflags,
+				       dev_name(port->dev),
+				       port);
+		if (ret) {
+			dev_err(port->dev, "unable to request IRQ %d\n",
+				mvuart->irq[UART_TX_IRQ]);
+			devm_free_irq(port->dev, mvuart->irq[UART_RX_IRQ],
+				      port);
+			return ret;
+		}
 	}
 
 	return 0;
@@ -354,9 +416,16 @@ static int mvebu_uart_startup(struct uart_port *port)
 
 static void mvebu_uart_shutdown(struct uart_port *port)
 {
+	struct mvebu_uart *mvuart = to_mvuart(port);
+
 	writel(0, port->membase + UART_INTR(port));
 
-	free_irq(port->irq, port);
+	if (!mvuart->irq[UART_TX_IRQ]) {
+		devm_free_irq(port->dev, mvuart->irq[UART_IRQ_SUM], port);
+	} else {
+		devm_free_irq(port->dev, mvuart->irq[UART_RX_IRQ], port);
+		devm_free_irq(port->dev, mvuart->irq[UART_TX_IRQ], port);
+	}
 }
 
 static int mvebu_uart_baud_rate_set(struct uart_port *port, unsigned int baud)
@@ -661,15 +730,14 @@ static int uart_num_counter;
 static int mvebu_uart_probe(struct platform_device *pdev)
 {
 	struct resource *reg = platform_get_resource(pdev, IORESOURCE_MEM, 0);
-	struct resource *irq = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
 	const struct of_device_id *match = of_match_device(mvebu_uart_of_match,
 							   &pdev->dev);
 	struct uart_port *port;
 	struct mvebu_uart *mvuart;
-	int ret, id;
+	int ret, id, irq;
 
-	if (!reg || !irq) {
-		dev_err(&pdev->dev, "no registers/irq defined\n");
+	if (!reg) {
+		dev_err(&pdev->dev, "no registers defined\n");
 		return -EINVAL;
 	}
 
@@ -700,7 +768,12 @@ static int mvebu_uart_probe(struct platform_device *pdev)
 	port->flags      = UPF_FIXED_PORT;
 	port->line       = pdev->id;
 
-	port->irq        = irq->start;
+	/*
+	 * IRQ number is not stored in this structure because we may have two of
+	 * them per port (RX and TX). Instead, use the driver UART structure
+	 * array so called ->irq[].
+	 */
+	port->irq        = 0;
 	port->irqflags   = 0;
 	port->mapbase    = reg->start;
 
@@ -735,6 +808,40 @@ static int mvebu_uart_probe(struct platform_device *pdev)
 			port->uartclk = clk_get_rate(mvuart->clk);
 	}
 
+	/* Manage interrupts */
+	memset(mvuart->irq, 0, UART_IRQ_COUNT);
+	if (platform_irq_count(pdev) == 1) {
+		/* Old bindings: no name on the single unamed UART0 IRQ */
+		irq = platform_get_irq(pdev, 0);
+		if (irq < 0) {
+			dev_err(&pdev->dev, "unable to get UART IRQ\n");
+			return irq;
+		}
+
+		mvuart->irq[UART_IRQ_SUM] = irq;
+	} else {
+		/*
+		 * New bindings: named interrupts (RX, TX) for both UARTS,
+		 * only make use of uart-rx and uart-tx interrupts, do not use
+		 * uart-sum of UART0 port.
+		 */
+		irq = platform_get_irq_byname(pdev, "uart-rx");
+		if (irq < 0) {
+			dev_err(&pdev->dev, "unable to get 'uart-rx' IRQ\n");
+			return irq;
+		}
+
+		mvuart->irq[UART_RX_IRQ] = irq;
+
+		irq = platform_get_irq_byname(pdev, "uart-tx");
+		if (irq < 0) {
+			dev_err(&pdev->dev, "unable to get 'uart-tx' IRQ\n");
+			return irq;
+		}
+
+		mvuart->irq[UART_TX_IRQ] = irq;
+	}
+
 	/* UART Soft Reset*/
 	writel(CTRL_SOFT_RST, port->membase + UART_CTRL(port));
 	udelay(1);
-- 
2.11.0

^ permalink raw reply related	[flat|nested] 29+ messages in thread

* [PATCH v2 11/16] serial: mvebu-uart: augment the maximum number of ports
  2017-10-13  9:01 [PATCH v2 00/16] Support armada-37xx second UART port Miquel Raynal
                   ` (9 preceding siblings ...)
  2017-10-13  9:01 ` [PATCH v2 10/16] serial: mvebu-uart: dissociate RX and TX interrupts Miquel Raynal
@ 2017-10-13  9:01 ` Miquel Raynal
  2017-10-13  9:01 ` [PATCH v2 12/16] serial: mvebu-uart: support extended port registers layout Miquel Raynal
                   ` (4 subsequent siblings)
  15 siblings, 0 replies; 29+ messages in thread
From: Miquel Raynal @ 2017-10-13  9:01 UTC (permalink / raw)
  To: linux-arm-kernel

A3700 boards may have up to two UART ports. Set the new limit to two
maximum UART ports.

Signed-off-by: Miquel Raynal <miquel.raynal@free-electrons.com>
Reviewed-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
---
 drivers/tty/serial/mvebu-uart.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/tty/serial/mvebu-uart.c b/drivers/tty/serial/mvebu-uart.c
index d0e749f6f052..1074054ee5be 100644
--- a/drivers/tty/serial/mvebu-uart.c
+++ b/drivers/tty/serial/mvebu-uart.c
@@ -74,7 +74,7 @@
 #define UART_BRDV		0x10
 #define  BRDV_BAUD_MASK         0x3FF
 
-#define MVEBU_NR_UARTS		1
+#define MVEBU_NR_UARTS		2
 
 #define MVEBU_UART_TYPE		"mvebu-uart"
 #define DRIVER_NAME		"mvebu_serial"
-- 
2.11.0

^ permalink raw reply related	[flat|nested] 29+ messages in thread

* [PATCH v2 12/16] serial: mvebu-uart: support extended port registers layout
  2017-10-13  9:01 [PATCH v2 00/16] Support armada-37xx second UART port Miquel Raynal
                   ` (10 preceding siblings ...)
  2017-10-13  9:01 ` [PATCH v2 11/16] serial: mvebu-uart: augment the maximum number of ports Miquel Raynal
@ 2017-10-13  9:01 ` Miquel Raynal
  2017-10-13  9:01 ` [PATCH v2 13/16] arm64: dts: marvell: armada-37xx: add UART clock Miquel Raynal
                   ` (3 subsequent siblings)
  15 siblings, 0 replies; 29+ messages in thread
From: Miquel Raynal @ 2017-10-13  9:01 UTC (permalink / raw)
  To: linux-arm-kernel

Define the missing register offsets and bit fields for the extended
UART port. Add a second driver data structure filled with its port data,
selected with the right compatible (marvell,armada-3700-uart-ext).

Signed-off-by: Miquel Raynal <miquel.raynal@free-electrons.com>
Reviewed-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
---
 drivers/tty/serial/mvebu-uart.c | 24 ++++++++++++++++++++++++
 1 file changed, 24 insertions(+)

diff --git a/drivers/tty/serial/mvebu-uart.c b/drivers/tty/serial/mvebu-uart.c
index 1074054ee5be..16b0a5aa14e2 100644
--- a/drivers/tty/serial/mvebu-uart.c
+++ b/drivers/tty/serial/mvebu-uart.c
@@ -39,10 +39,13 @@
 
 /* Register Map */
 #define UART_STD_RBR		0x00
+#define UART_EXT_RBR		0x18
 
 #define UART_STD_TSH		0x04
+#define UART_EXT_TSH		0x1C
 
 #define UART_STD_CTRL1		0x08
+#define UART_EXT_CTRL1		0x04
 #define  CTRL_SOFT_RST		BIT(31)
 #define  CTRL_TXFIFO_RST	BIT(15)
 #define  CTRL_RXFIFO_RST	BIT(14)
@@ -55,15 +58,20 @@
 				CTRL_PAR_ERR_INT | CTRL_OVR_ERR_INT)
 
 #define UART_STD_CTRL2		UART_STD_CTRL1
+#define UART_EXT_CTRL2		0x20
 #define  CTRL_STD_TX_RDY_INT	BIT(5)
+#define  CTRL_EXT_TX_RDY_INT	BIT(6)
 #define  CTRL_STD_RX_RDY_INT	BIT(4)
+#define  CTRL_EXT_RX_RDY_INT	BIT(5)
 
 #define UART_STAT		0x0C
 #define  STAT_TX_FIFO_EMP	BIT(13)
 #define  STAT_TX_FIFO_FUL	BIT(11)
 #define  STAT_TX_EMP		BIT(6)
 #define  STAT_STD_TX_RDY	BIT(5)
+#define  STAT_EXT_TX_RDY	BIT(15)
 #define  STAT_STD_RX_RDY	BIT(4)
+#define  STAT_EXT_RX_RDY	BIT(14)
 #define  STAT_BRK_DET		BIT(3)
 #define  STAT_FRM_ERR		BIT(2)
 #define  STAT_PAR_ERR		BIT(1)
@@ -865,12 +873,28 @@ static struct mvebu_uart_driver_data uart_std_driver_data = {
 	.flags.stat_rx_rdy = STAT_STD_RX_RDY,
 };
 
+static struct mvebu_uart_driver_data uart_ext_driver_data = {
+	.is_ext = true,
+	.regs.rbr = UART_EXT_RBR,
+	.regs.tsh = UART_EXT_TSH,
+	.regs.ctrl = UART_EXT_CTRL1,
+	.regs.intr = UART_EXT_CTRL2,
+	.flags.ctrl_tx_rdy_int = CTRL_EXT_TX_RDY_INT,
+	.flags.ctrl_rx_rdy_int = CTRL_EXT_RX_RDY_INT,
+	.flags.stat_tx_rdy = STAT_EXT_TX_RDY,
+	.flags.stat_rx_rdy = STAT_EXT_RX_RDY,
+};
+
 /* Match table for of_platform binding */
 static const struct of_device_id mvebu_uart_of_match[] = {
 	{
 		.compatible = "marvell,armada-3700-uart",
 		.data = (void *)&uart_std_driver_data,
 	},
+	{
+		.compatible = "marvell,armada-3700-uart-ext",
+		.data = (void *)&uart_ext_driver_data,
+	},
 	{}
 };
 
-- 
2.11.0

^ permalink raw reply related	[flat|nested] 29+ messages in thread

* [PATCH v2 13/16] arm64: dts: marvell: armada-37xx: add UART clock
  2017-10-13  9:01 [PATCH v2 00/16] Support armada-37xx second UART port Miquel Raynal
                   ` (11 preceding siblings ...)
  2017-10-13  9:01 ` [PATCH v2 12/16] serial: mvebu-uart: support extended port registers layout Miquel Raynal
@ 2017-10-13  9:01 ` Miquel Raynal
  2017-10-30 15:45   ` Gregory CLEMENT
  2017-10-13  9:01 ` [PATCH v2 14/16] arm64: dts: marvell: armada-37xx: add second UART port Miquel Raynal
                   ` (2 subsequent siblings)
  15 siblings, 1 reply; 29+ messages in thread
From: Miquel Raynal @ 2017-10-13  9:01 UTC (permalink / raw)
  To: linux-arm-kernel

Add the missing clock property to armada-3700 UART node.

This clock will be used to derive the prescaler value to comply with
the requested baudrate.

Signed-off-by: Miquel Raynal <miquel.raynal@free-electrons.com>
Acked-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
---
 arch/arm64/boot/dts/marvell/armada-37xx.dtsi | 1 +
 1 file changed, 1 insertion(+)

diff --git a/arch/arm64/boot/dts/marvell/armada-37xx.dtsi b/arch/arm64/boot/dts/marvell/armada-37xx.dtsi
index b554cdaf5e53..a36d667f770e 100644
--- a/arch/arm64/boot/dts/marvell/armada-37xx.dtsi
+++ b/arch/arm64/boot/dts/marvell/armada-37xx.dtsi
@@ -135,6 +135,7 @@
 			uart0: serial at 12000 {
 				compatible = "marvell,armada-3700-uart";
 				reg = <0x12000 0x200>;
+				clocks = <&xtalclk>;
 				interrupts = <GIC_SPI 11 IRQ_TYPE_LEVEL_HIGH>;
 				status = "disabled";
 			};
-- 
2.11.0

^ permalink raw reply related	[flat|nested] 29+ messages in thread

* [PATCH v2 14/16] arm64: dts: marvell: armada-37xx: add second UART port
  2017-10-13  9:01 [PATCH v2 00/16] Support armada-37xx second UART port Miquel Raynal
                   ` (12 preceding siblings ...)
  2017-10-13  9:01 ` [PATCH v2 13/16] arm64: dts: marvell: armada-37xx: add UART clock Miquel Raynal
@ 2017-10-13  9:01 ` Miquel Raynal
  2017-10-30 15:45   ` Gregory CLEMENT
  2017-10-13  9:01 ` [PATCH v2 15/16] arm64: dts: marvell: armada-3720-db: enable " Miquel Raynal
  2017-10-13  9:02 ` [PATCH v2 16/16] arm64: dts: marvell: armada-3720-espressobin: fill UART nodes Miquel Raynal
  15 siblings, 1 reply; 29+ messages in thread
From: Miquel Raynal @ 2017-10-13  9:01 UTC (permalink / raw)
  To: linux-arm-kernel

Add a node in Armada 37xx DTSI file for the second UART, with a
different compatible due to its extended IP which has some
differences with the first UART already in place.

Make use of this commit to also fully describe the first port and
use the same clear and named interrupt bindings for both ports.

The standard UART (UART0) uses level-interrupts while the extended
UART (UART1) uses edge-triggered interrupts.

Signed-off-by: Miquel Raynal <miquel.raynal@free-electrons.com>
Acked-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
---
 arch/arm64/boot/dts/marvell/armada-37xx.dtsi | 18 +++++++++++++++++-
 1 file changed, 17 insertions(+), 1 deletion(-)

diff --git a/arch/arm64/boot/dts/marvell/armada-37xx.dtsi b/arch/arm64/boot/dts/marvell/armada-37xx.dtsi
index a36d667f770e..72b68f23c001 100644
--- a/arch/arm64/boot/dts/marvell/armada-37xx.dtsi
+++ b/arch/arm64/boot/dts/marvell/armada-37xx.dtsi
@@ -55,6 +55,7 @@
 
 	aliases {
 		serial0 = &uart0;
+		serial1 = &uart1;
 	};
 
 	cpus {
@@ -136,7 +137,22 @@
 				compatible = "marvell,armada-3700-uart";
 				reg = <0x12000 0x200>;
 				clocks = <&xtalclk>;
-				interrupts = <GIC_SPI 11 IRQ_TYPE_LEVEL_HIGH>;
+				interrupts =
+				<GIC_SPI 11 IRQ_TYPE_LEVEL_HIGH>,
+				<GIC_SPI 12 IRQ_TYPE_LEVEL_HIGH>,
+				<GIC_SPI 13 IRQ_TYPE_LEVEL_HIGH>;
+				interrupt-names = "uart-sum", "uart-tx", "uart-rx";
+				status = "disabled";
+			};
+
+			uart1: serial at 12200 {
+				compatible = "marvell,armada-3700-uart-ext";
+				reg = <0x12200 0x30>;
+				clocks = <&xtalclk>;
+				interrupts =
+				<GIC_SPI 30 IRQ_TYPE_EDGE_RISING>,
+				<GIC_SPI 31 IRQ_TYPE_EDGE_RISING>;
+				interrupt-names = "uart-tx", "uart-rx";
 				status = "disabled";
 			};
 
-- 
2.11.0

^ permalink raw reply related	[flat|nested] 29+ messages in thread

* [PATCH v2 15/16] arm64: dts: marvell: armada-3720-db: enable second UART port
  2017-10-13  9:01 [PATCH v2 00/16] Support armada-37xx second UART port Miquel Raynal
                   ` (13 preceding siblings ...)
  2017-10-13  9:01 ` [PATCH v2 14/16] arm64: dts: marvell: armada-37xx: add second UART port Miquel Raynal
@ 2017-10-13  9:01 ` Miquel Raynal
  2017-10-30 15:46   ` Gregory CLEMENT
  2017-10-13  9:02 ` [PATCH v2 16/16] arm64: dts: marvell: armada-3720-espressobin: fill UART nodes Miquel Raynal
  15 siblings, 1 reply; 29+ messages in thread
From: Miquel Raynal @ 2017-10-13  9:01 UTC (permalink / raw)
  To: linux-arm-kernel

Enable Armada-3720-DB second UART port by adding the corresponding
device tree node in the board DTS and enabling it.

Signed-off-by: Miquel Raynal <miquel.raynal@free-electrons.com>
Acked-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
---
 arch/arm64/boot/dts/marvell/armada-3720-db.dts | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/arch/arm64/boot/dts/marvell/armada-3720-db.dts b/arch/arm64/boot/dts/marvell/armada-3720-db.dts
index 9df0f06ce607..15713c19b3d0 100644
--- a/arch/arm64/boot/dts/marvell/armada-3720-db.dts
+++ b/arch/arm64/boot/dts/marvell/armada-3720-db.dts
@@ -216,7 +216,7 @@
 
 /*
  * Exported on the micro USB connector CON30(V2.0)/CON32(V1.4) through
- * an FTDI
+ * an FTDI (also on CON24(V2.0)/CON26(V1.4)).
  */
 &uart0 {
 	pinctrl-names = "default";
@@ -224,6 +224,13 @@
 	status = "okay";
 };
 
+/* CON26(V2.0)/CON28(V1.4) */
+&uart1 {
+	pinctrl-names = "default";
+	pinctrl-0 = <&uart2_pins>;
+	status = "okay";
+};
+
 /* CON27(V2.0)/CON29(V1.4) */
 &usb2 {
 	status = "okay";
-- 
2.11.0

^ permalink raw reply related	[flat|nested] 29+ messages in thread

* [PATCH v2 16/16] arm64: dts: marvell: armada-3720-espressobin: fill UART nodes
  2017-10-13  9:01 [PATCH v2 00/16] Support armada-37xx second UART port Miquel Raynal
                   ` (14 preceding siblings ...)
  2017-10-13  9:01 ` [PATCH v2 15/16] arm64: dts: marvell: armada-3720-db: enable " Miquel Raynal
@ 2017-10-13  9:02 ` Miquel Raynal
  2017-10-30 15:46   ` Gregory CLEMENT
  15 siblings, 1 reply; 29+ messages in thread
From: Miquel Raynal @ 2017-10-13  9:02 UTC (permalink / raw)
  To: linux-arm-kernel

Fill ESPRESSObin uart0 node with pinctrl information like in the
Armada-3720-DB device tree (which uses the same node).

Also explain how to enable the second UART port available on the
headers. This second port is not enabled by default because both
headers are dedicated to expose general purpose pins and remapping
some of them to use the second UART would break existing users.

Suggested-by: L?szl? ?SHIN <laszlo@ashin.hu>
Signed-off-by: Miquel Raynal <miquel.raynal@free-electrons.com>
---

Changes since v1: comment about UART1 node.

 arch/arm64/boot/dts/marvell/armada-3720-espressobin.dts | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/arch/arm64/boot/dts/marvell/armada-3720-espressobin.dts b/arch/arm64/boot/dts/marvell/armada-3720-espressobin.dts
index 2ce52ba74f73..bdfb5553ddb5 100644
--- a/arch/arm64/boot/dts/marvell/armada-3720-espressobin.dts
+++ b/arch/arm64/boot/dts/marvell/armada-3720-espressobin.dts
@@ -98,9 +98,21 @@
 
 /* Exported on the micro USB connector J5 through an FTDI */
 &uart0 {
+	pinctrl-names = "default";
+	pinctrl-0 = <&uart1_pins>;
 	status = "okay";
 };
 
+/*
+ * Connector J17 and J18 expose a number of different features. Some pins are
+ * multiplexed. This is the case for instance for the following features:
+ * - UART1 (pin 24 = RX, pin 26 = TX). See armada-3720-db.dts for an example of
+ *   how to enable it. Beware that the signals are 1.8V TTL.
+ * - I2C
+ * - SPI
+ * - MMC
+ */
+
 /* J7 */
 &usb3 {
 	status = "okay";
-- 
2.11.0

^ permalink raw reply related	[flat|nested] 29+ messages in thread

* [PATCH v2 04/16] serial: mvebu-uart: support probe of multiple ports
  2017-10-13  9:01 ` [PATCH v2 04/16] serial: mvebu-uart: support probe of multiple ports Miquel Raynal
@ 2017-10-13  9:40   ` Gregory CLEMENT
  2017-10-13 11:17     ` Miquel RAYNAL
  0 siblings, 1 reply; 29+ messages in thread
From: Gregory CLEMENT @ 2017-10-13  9:40 UTC (permalink / raw)
  To: linux-arm-kernel

Hi Miquel,
 
 On ven., oct. 13 2017, Miquel Raynal <miquel.raynal@free-electrons.com> wrote:

> -	port = &mvebu_uart_ports[0];
> +	/* Assume that all UART ports have a DT alias or none has */
> +	id = of_alias_get_id(pdev->dev.of_node, "serial");

You stil need to check the pdev->dev.of_node before calling
of_alias_get_id.

Once it will be fixed, you can add:

Acked-by: Gregory CLEMENT <gregory.clement@free-electrons.com>

Thanks,

Gregory


> +	if (!pdev->dev.of_node || id < 0)
> +		pdev->id = uart_num_counter++;
> +	else
> +		pdev->id = id;
> +
> +	if (pdev->id >= MVEBU_NR_UARTS) {
> +		dev_err(&pdev->dev, "cannot have more than %d UART ports\n",
> +			MVEBU_NR_UARTS);
> +		return -EINVAL;
> +	}
> +
> +	port = &mvebu_uart_ports[pdev->id];
>  
>  	spin_lock_init(&port->lock);
>  
> @@ -572,7 +588,7 @@ static int mvebu_uart_probe(struct platform_device *pdev)
>  	port->fifosize   = 32;
>  	port->iotype     = UPIO_MEM32;
>  	port->flags      = UPF_FIXED_PORT;
> -	port->line       = 0; /* single port: force line number to  0 */
> +	port->line       = pdev->id;
>  
>  	port->irq        = irq->start;
>  	port->irqflags   = 0;
> -- 
> 2.11.0
>

-- 
Gregory Clement, Free Electrons
Kernel, drivers, real-time and embedded Linux
development, consulting, training and support.
http://free-electrons.com

^ permalink raw reply	[flat|nested] 29+ messages in thread

* [PATCH v2 04/16] serial: mvebu-uart: support probe of multiple ports
  2017-10-13  9:40   ` Gregory CLEMENT
@ 2017-10-13 11:17     ` Miquel RAYNAL
  2017-10-13 11:22       ` Gregory CLEMENT
  0 siblings, 1 reply; 29+ messages in thread
From: Miquel RAYNAL @ 2017-10-13 11:17 UTC (permalink / raw)
  To: linux-arm-kernel

Hi Gregory,

On Fri, 13 Oct 2017 11:40:32 +0200
Gregory CLEMENT <gregory.clement@free-electrons.com> wrote:

> Hi Miquel,
>  
>  On ven., oct. 13 2017, Miquel Raynal
> <miquel.raynal@free-electrons.com> wrote:
> 
> > -	port = &mvebu_uart_ports[0];
> > +	/* Assume that all UART ports have a DT alias or none has
> > */
> > +	id = of_alias_get_id(pdev->dev.of_node, "serial");  
> 
> You stil need to check the pdev->dev.of_node before calling
> of_alias_get_id.

Thanks for your feedback but I don't think we still need to check it,
because the of_alias_get_id() function will either return -ENOSYS if
CONFIG_OF is not defined, or -ENODEV if the node is not found. As the
function does not dereference pdev->dev.of_node at any moment but
instead compares the value with another pointer, I think this call is
safe like this.

Thanks,
Miqu?l

> 
> Once it will be fixed, you can add:
> 
> Acked-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
> 
> Thanks,
> 
> Gregory
> 
> 
> > +	if (!pdev->dev.of_node || id < 0)
> > +		pdev->id = uart_num_counter++;
> > +	else
> > +		pdev->id = id;
> > +
> > +	if (pdev->id >= MVEBU_NR_UARTS) {
> > +		dev_err(&pdev->dev, "cannot have more than %d UART
> > ports\n",
> > +			MVEBU_NR_UARTS);
> > +		return -EINVAL;
> > +	}
> > +
> > +	port = &mvebu_uart_ports[pdev->id];
> >  
> >  	spin_lock_init(&port->lock);
> >  
> > @@ -572,7 +588,7 @@ static int mvebu_uart_probe(struct
> > platform_device *pdev) port->fifosize   = 32;
> >  	port->iotype     = UPIO_MEM32;
> >  	port->flags      = UPF_FIXED_PORT;
> > -	port->line       = 0; /* single port: force line number
> > to  0 */
> > +	port->line       = pdev->id;
> >  
> >  	port->irq        = irq->start;
> >  	port->irqflags   = 0;
> > -- 
> > 2.11.0
> >  
> 



-- 
Miquel Raynal, Free Electrons
Embedded Linux and Kernel engineering
http://free-electrons.com

^ permalink raw reply	[flat|nested] 29+ messages in thread

* [PATCH v2 04/16] serial: mvebu-uart: support probe of multiple ports
  2017-10-13 11:17     ` Miquel RAYNAL
@ 2017-10-13 11:22       ` Gregory CLEMENT
  0 siblings, 0 replies; 29+ messages in thread
From: Gregory CLEMENT @ 2017-10-13 11:22 UTC (permalink / raw)
  To: linux-arm-kernel

Hi Miquel,
 
 On ven., oct. 13 2017, Miquel RAYNAL <miquel.raynal@free-electrons.com> wrote:

> Hi Gregory,
>
> On Fri, 13 Oct 2017 11:40:32 +0200
> Gregory CLEMENT <gregory.clement@free-electrons.com> wrote:
>
>> Hi Miquel,
>>  
>>  On ven., oct. 13 2017, Miquel Raynal
>> <miquel.raynal@free-electrons.com> wrote:
>> 
>> > -	port = &mvebu_uart_ports[0];
>> > +	/* Assume that all UART ports have a DT alias or none has
>> > */
>> > +	id = of_alias_get_id(pdev->dev.of_node, "serial");  
>> 
>> You stil need to check the pdev->dev.of_node before calling
>> of_alias_get_id.
>
> Thanks for your feedback but I don't think we still need to check it,
> because the of_alias_get_id() function will either return -ENOSYS if
> CONFIG_OF is not defined, or -ENODEV if the node is not found. As the
> function does not dereference pdev->dev.of_node at any moment but
> instead compares the value with another pointer, I think this call is
> safe like this.

Fair enough, I expected that the pointer was dereferenced but I was
wrong, was so no need for a new version.

Acked-by: Gregory CLEMENT <gregory.clement@free-electrons.com>

Thanks,

Gregory

>
> Thanks,
> Miqu?l
>
>> 
>> Once it will be fixed, you can add:
>> 
>> Acked-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
>> 
>> Thanks,
>> 
>> Gregory
>> 
>> 
>> > +	if (!pdev->dev.of_node || id < 0)
>> > +		pdev->id = uart_num_counter++;
>> > +	else
>> > +		pdev->id = id;
>> > +
>> > +	if (pdev->id >= MVEBU_NR_UARTS) {
>> > +		dev_err(&pdev->dev, "cannot have more than %d UART
>> > ports\n",
>> > +			MVEBU_NR_UARTS);
>> > +		return -EINVAL;
>> > +	}
>> > +
>> > +	port = &mvebu_uart_ports[pdev->id];
>> >  
>> >  	spin_lock_init(&port->lock);
>> >  
>> > @@ -572,7 +588,7 @@ static int mvebu_uart_probe(struct
>> > platform_device *pdev) port->fifosize   = 32;
>> >  	port->iotype     = UPIO_MEM32;
>> >  	port->flags      = UPF_FIXED_PORT;
>> > -	port->line       = 0; /* single port: force line number
>> > to  0 */
>> > +	port->line       = pdev->id;
>> >  
>> >  	port->irq        = irq->start;
>> >  	port->irqflags   = 0;
>> > -- 
>> > 2.11.0
>> >  
>> 
>
>
>
> -- 
> Miquel Raynal, Free Electrons
> Embedded Linux and Kernel engineering
> http://free-electrons.com

-- 
Gregory Clement, Free Electrons
Kernel, drivers, real-time and embedded Linux
development, consulting, training and support.
http://free-electrons.com

^ permalink raw reply	[flat|nested] 29+ messages in thread

* [PATCH v2 02/16] pinctrl: dt-bindings: Fix A37xx uart2 group name
  2017-10-13  9:01 ` [PATCH v2 02/16] pinctrl: dt-bindings: Fix A37xx uart2 group name Miquel Raynal
@ 2017-10-16 11:56   ` Linus Walleij
  0 siblings, 0 replies; 29+ messages in thread
From: Linus Walleij @ 2017-10-16 11:56 UTC (permalink / raw)
  To: linux-arm-kernel

On Fri, Oct 13, 2017 at 11:01 AM, Miquel Raynal
<miquel.raynal@free-electrons.com> wrote:

> Fix a typo in A37xx pin controllers documentation about uart2 pin group.
>
> Signed-off-by: Miquel Raynal <miquel.raynal@free-electrons.com>
> Reviewed-by: Gregory CLEMENT <gregory.clement@free-electrons.com>

Patch applied to the pinctrl tree.

Yours,
Linus Walleij

^ permalink raw reply	[flat|nested] 29+ messages in thread

* [PATCH v2 01/16] dt-bindings: mvebu-uart: update documentation with extended UART
  2017-10-13  9:01 ` [PATCH v2 01/16] dt-bindings: mvebu-uart: update documentation with extended UART Miquel Raynal
@ 2017-10-17 22:00   ` Rob Herring
  2017-10-18  6:25     ` Miquel RAYNAL
  0 siblings, 1 reply; 29+ messages in thread
From: Rob Herring @ 2017-10-17 22:00 UTC (permalink / raw)
  To: linux-arm-kernel

On Fri, Oct 13, 2017 at 11:01:45AM +0200, Miquel Raynal wrote:
> Update the Device Tree binding documentation for the Marvell EBU UART,
> in order to allow describing the extended UART IP block, in addition to
> the already supported standard UART IP. This requires adding a new
> compatible string, the introduction of a clocks property, and extensions
> to the interrupts property.
> 
> Signed-off-by: Miquel Raynal <miquel.raynal@free-electrons.com>
> Reviewed-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
> ---
>  .../devicetree/bindings/serial/mvebu-uart.txt      | 49 +++++++++++++++++++---
>  1 file changed, 44 insertions(+), 5 deletions(-)
> 
> diff --git a/Documentation/devicetree/bindings/serial/mvebu-uart.txt b/Documentation/devicetree/bindings/serial/mvebu-uart.txt
> index d37fabe17bd1..3df3a3fab4bb 100644
> --- a/Documentation/devicetree/bindings/serial/mvebu-uart.txt
> +++ b/Documentation/devicetree/bindings/serial/mvebu-uart.txt
> @@ -1,13 +1,52 @@
> -* Marvell UART : Non standard UART used in some of Marvell EBU SoCs (e.g., Armada-3700)
> +* Marvell UART : Non standard UART used in some of Marvell EBU SoCs
> +                 e.g., Armada-3700.
>  
>  Required properties:
> -- compatible: "marvell,armada-3700-uart"
> +- compatible:
> +    - "marvell,armada-3700-uart" for the standard variant of the UART
> +      (32 bytes FIFO, no DMA, level interrupts, 8-bit access to the
> +      FIFO, baudrate limited to 230400).
> +    - "marvell,armada-3700-uart-ext" for the extended variant of the
> +      UART (128 bytes FIFO, DMA, front interrupts, 8-bit or 32-bit
> +      accesses to the FIFO, baudrate unlimited by the dividers).

What do you call the next extended version? marvell,armada-3700-uart-ext-ext?

This is different versions of UART on the same chip?

>  - reg: offset and length of the register set for the device.
> -- interrupts: device interrupt
> +- clocks: UART reference clock used to derive the baudrate (only
> +      mandatory with "marvell,armada-3700-uart-ext" compatible).

How is this optional? The freq is fixed if not present? If so, what 
frequency?

> +- interrupts:
> +    - Must contain three elements for the standard variant of the IP
> +      (marvell,armada-3700-uart): "uart-sum", "uart-tx" and "uart-rx",
> +      respectively the UART sum interrupt, the UART TX interrupt and
> +      UART RX interrupt. A corresponding interrupt-names property must
> +      be defined.
> +    - Must contain two elements for the extended variant of the IP
> +      (marvell,armada-3700-uart-ext): "uart-tx" and "uart-rx",
> +      respectively the UART TX interrupt and the UART RX interrupt. A
> +      corresponding interrupts-names property must be defined.
> +    - For backward compatibility reasons, a single element interrupts
> +      property is also supported for the standard variant of the IP,
> +      containing only the UART sum interrupt. This form is deprecated
> +      and should no longer be used.
>  
>  Example:
> -	serial at 12000 {
> +	uart0: serial at 12000 {
>  		compatible = "marvell,armada-3700-uart";
>  		reg = <0x12000 0x200>;
> -		interrupts = <43>;
> +		clocks = <&xtalclk>;
> +		interrupts =
> +		<GIC_SPI 11 IRQ_TYPE_LEVEL_HIGH>,
> +		<GIC_SPI 12 IRQ_TYPE_LEVEL_HIGH>,
> +		<GIC_SPI 13 IRQ_TYPE_LEVEL_HIGH>;
> +		interrupt-names = "uart-sum", "uart-tx", "uart-rx";
> +		status = "disabled";

Don't show status in examples.

> +	};
> +
> +	uart1: serial at 12200 {
> +		compatible = "marvell,armada-3700-uart-ext";
> +		reg = <0x12200 0x30>;
> +		clocks = <&xtalclk>;
> +		interrupts =
> +		<GIC_SPI 30 IRQ_TYPE_EDGE_RISING>,
> +		<GIC_SPI 31 IRQ_TYPE_EDGE_RISING>;
> +		interrupt-names = "uart-tx", "uart-rx";
> +		status = "disabled";
>  	};
> -- 
> 2.11.0
> 
> --
> To unsubscribe from this list: send the line "unsubscribe devicetree" in
> the body of a message to majordomo at vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html

^ permalink raw reply	[flat|nested] 29+ messages in thread

* [PATCH v2 01/16] dt-bindings: mvebu-uart: update documentation with extended UART
  2017-10-17 22:00   ` Rob Herring
@ 2017-10-18  6:25     ` Miquel RAYNAL
  2017-10-18 13:29       ` Rob Herring
  0 siblings, 1 reply; 29+ messages in thread
From: Miquel RAYNAL @ 2017-10-18  6:25 UTC (permalink / raw)
  To: linux-arm-kernel

Hi Rob,

On Tue, 17 Oct 2017 17:00:22 -0500
Rob Herring <robh@kernel.org> wrote:

> On Fri, Oct 13, 2017 at 11:01:45AM +0200, Miquel Raynal wrote:
> > Update the Device Tree binding documentation for the Marvell EBU
> > UART, in order to allow describing the extended UART IP block, in
> > addition to the already supported standard UART IP. This requires
> > adding a new compatible string, the introduction of a clocks
> > property, and extensions to the interrupts property.
> > 
> > Signed-off-by: Miquel Raynal <miquel.raynal@free-electrons.com>
> > Reviewed-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
> > ---
> >  .../devicetree/bindings/serial/mvebu-uart.txt      | 49
> > +++++++++++++++++++--- 1 file changed, 44 insertions(+), 5
> > deletions(-)
> > 
> > diff --git
> > a/Documentation/devicetree/bindings/serial/mvebu-uart.txt
> > b/Documentation/devicetree/bindings/serial/mvebu-uart.txt index
> > d37fabe17bd1..3df3a3fab4bb 100644 ---
> > a/Documentation/devicetree/bindings/serial/mvebu-uart.txt +++
> > b/Documentation/devicetree/bindings/serial/mvebu-uart.txt @@ -1,13
> > +1,52 @@ -* Marvell UART : Non standard UART used in some of
> > Marvell EBU SoCs (e.g., Armada-3700) +* Marvell UART : Non standard
> > UART used in some of Marvell EBU SoCs
> > +                 e.g., Armada-3700.
> >  
> >  Required properties:
> > -- compatible: "marvell,armada-3700-uart"
> > +- compatible:
> > +    - "marvell,armada-3700-uart" for the standard variant of the
> > UART
> > +      (32 bytes FIFO, no DMA, level interrupts, 8-bit access to the
> > +      FIFO, baudrate limited to 230400).
> > +    - "marvell,armada-3700-uart-ext" for the extended variant of
> > the
> > +      UART (128 bytes FIFO, DMA, front interrupts, 8-bit or 32-bit
> > +      accesses to the FIFO, baudrate unlimited by the dividers).  
> 
> What do you call the next extended version?
> marvell,armada-3700-uart-ext-ext?

I don't know what you mean by "next extended version"?

> 
> This is different versions of UART on the same chip?

Today in mainline there is support for the A3700 UART IP.
This series add support for another IP, based on the A3700, but with
extended features (explaining the -ext suffix).

Can you precise what is bothering you?

> 
> >  - reg: offset and length of the register set for the device.
> > -- interrupts: device interrupt
> > +- clocks: UART reference clock used to derive the baudrate (only
> > +      mandatory with "marvell,armada-3700-uart-ext" compatible).  
> 
> How is this optional? The freq is fixed if not present? If so, what 
> frequency?

The "clocks" property should not be optional at all but that is how the
bindings were handled before this series, so I can't tell now that
this property is mandatory as it would break compatibility with older
versions of the driver.

When no clock is provided, the frequency is fixed by the bootloader
and cannot be changed. There is no standard frequency for it but the
one chosen by the bootloader often is 115200 as the UART is usually
used as the serial console.

Because the bootloader does only initialize the UART in use for the
serial console, the clock is mandatory when using another port or it
will not work at all.

> 
> > +- interrupts:
> > +    - Must contain three elements for the standard variant of the
> > IP
> > +      (marvell,armada-3700-uart): "uart-sum", "uart-tx" and
> > "uart-rx",
> > +      respectively the UART sum interrupt, the UART TX interrupt
> > and
> > +      UART RX interrupt. A corresponding interrupt-names property
> > must
> > +      be defined.
> > +    - Must contain two elements for the extended variant of the IP
> > +      (marvell,armada-3700-uart-ext): "uart-tx" and "uart-rx",
> > +      respectively the UART TX interrupt and the UART RX
> > interrupt. A
> > +      corresponding interrupts-names property must be defined.
> > +    - For backward compatibility reasons, a single element
> > interrupts
> > +      property is also supported for the standard variant of the
> > IP,
> > +      containing only the UART sum interrupt. This form is
> > deprecated
> > +      and should no longer be used.
> >  
> >  Example:
> > -	serial at 12000 {
> > +	uart0: serial at 12000 {
> >  		compatible = "marvell,armada-3700-uart";
> >  		reg = <0x12000 0x200>;
> > -		interrupts = <43>;
> > +		clocks = <&xtalclk>;
> > +		interrupts =
> > +		<GIC_SPI 11 IRQ_TYPE_LEVEL_HIGH>,
> > +		<GIC_SPI 12 IRQ_TYPE_LEVEL_HIGH>,
> > +		<GIC_SPI 13 IRQ_TYPE_LEVEL_HIGH>;
> > +		interrupt-names = "uart-sum", "uart-tx", "uart-rx";
> > +		status = "disabled";  
> 
> Don't show status in examples.

Ok.

> 
> > +	};
> > +
> > +	uart1: serial at 12200 {
> > +		compatible = "marvell,armada-3700-uart-ext";
> > +		reg = <0x12200 0x30>;
> > +		clocks = <&xtalclk>;
> > +		interrupts =
> > +		<GIC_SPI 30 IRQ_TYPE_EDGE_RISING>,
> > +		<GIC_SPI 31 IRQ_TYPE_EDGE_RISING>;
> > +		interrupt-names = "uart-tx", "uart-rx";
> > +		status = "disabled";
> >  	};
> > -- 
> > 2.11.0
> > 
> > --
> > To unsubscribe from this list: send the line "unsubscribe
> > devicetree" in the body of a message to majordomo at vger.kernel.org
> > More majordomo info at  http://vger.kernel.org/majordomo-info.html  

Thanks,
Miqu?l

-- 
Miquel Raynal, Free Electrons
Embedded Linux and Kernel engineering
http://free-electrons.com

^ permalink raw reply	[flat|nested] 29+ messages in thread

* [PATCH v2 01/16] dt-bindings: mvebu-uart: update documentation with extended UART
  2017-10-18  6:25     ` Miquel RAYNAL
@ 2017-10-18 13:29       ` Rob Herring
  2017-10-19  7:36         ` Miquel RAYNAL
  0 siblings, 1 reply; 29+ messages in thread
From: Rob Herring @ 2017-10-18 13:29 UTC (permalink / raw)
  To: linux-arm-kernel

On Wed, Oct 18, 2017 at 1:25 AM, Miquel RAYNAL
<miquel.raynal@free-electrons.com> wrote:
> Hi Rob,
>
> On Tue, 17 Oct 2017 17:00:22 -0500
> Rob Herring <robh@kernel.org> wrote:
>
>> On Fri, Oct 13, 2017 at 11:01:45AM +0200, Miquel Raynal wrote:
>> > Update the Device Tree binding documentation for the Marvell EBU
>> > UART, in order to allow describing the extended UART IP block, in
>> > addition to the already supported standard UART IP. This requires
>> > adding a new compatible string, the introduction of a clocks
>> > property, and extensions to the interrupts property.
>> >
>> > Signed-off-by: Miquel Raynal <miquel.raynal@free-electrons.com>
>> > Reviewed-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
>> > ---
>> >  .../devicetree/bindings/serial/mvebu-uart.txt      | 49
>> > +++++++++++++++++++--- 1 file changed, 44 insertions(+), 5
>> > deletions(-)
>> >
>> > diff --git
>> > a/Documentation/devicetree/bindings/serial/mvebu-uart.txt
>> > b/Documentation/devicetree/bindings/serial/mvebu-uart.txt index
>> > d37fabe17bd1..3df3a3fab4bb 100644 ---
>> > a/Documentation/devicetree/bindings/serial/mvebu-uart.txt +++
>> > b/Documentation/devicetree/bindings/serial/mvebu-uart.txt @@ -1,13
>> > +1,52 @@ -* Marvell UART : Non standard UART used in some of
>> > Marvell EBU SoCs (e.g., Armada-3700) +* Marvell UART : Non standard
>> > UART used in some of Marvell EBU SoCs
>> > +                 e.g., Armada-3700.
>> >
>> >  Required properties:
>> > -- compatible: "marvell,armada-3700-uart"
>> > +- compatible:
>> > +    - "marvell,armada-3700-uart" for the standard variant of the
>> > UART
>> > +      (32 bytes FIFO, no DMA, level interrupts, 8-bit access to the
>> > +      FIFO, baudrate limited to 230400).
>> > +    - "marvell,armada-3700-uart-ext" for the extended variant of
>> > the
>> > +      UART (128 bytes FIFO, DMA, front interrupts, 8-bit or 32-bit
>> > +      accesses to the FIFO, baudrate unlimited by the dividers).
>>
>> What do you call the next extended version?
>> marvell,armada-3700-uart-ext-ext?
>
> I don't know what you mean by "next extended version"?

IP evolves on new chips with new features. Just trying to understand
how you are

>> This is different versions of UART on the same chip?
>
> Today in mainline there is support for the A3700 UART IP.
> This series add support for another IP, based on the A3700, but with
> extended features (explaining the -ext suffix).
>
> Can you precise what is bothering you?

Is this different versions of UART IP on 1 chip or a new version of
the UART IP on a new SoC? The latter should be a new compatible with
the new SoC. The former case does happen some, but is not common. I'm
just trying to understand which applies here.


>> >  - reg: offset and length of the register set for the device.
>> > -- interrupts: device interrupt
>> > +- clocks: UART reference clock used to derive the baudrate (only
>> > +      mandatory with "marvell,armada-3700-uart-ext" compatible).
>>
>> How is this optional? The freq is fixed if not present? If so, what
>> frequency?
>
> The "clocks" property should not be optional at all but that is how the
> bindings were handled before this series, so I can't tell now that
> this property is mandatory as it would break compatibility with older
> versions of the driver.

Okay. I think it should be mandatory with a note how missing property
is handled.

> When no clock is provided, the frequency is fixed by the bootloader
> and cannot be changed. There is no standard frequency for it but the
> one chosen by the bootloader often is 115200 as the UART is usually
> used as the serial console.
>
> Because the bootloader does only initialize the UART in use for the
> serial console, the clock is mandatory when using another port or it
> will not work at all.

^ permalink raw reply	[flat|nested] 29+ messages in thread

* [PATCH v2 01/16] dt-bindings: mvebu-uart: update documentation with extended UART
  2017-10-18 13:29       ` Rob Herring
@ 2017-10-19  7:36         ` Miquel RAYNAL
  0 siblings, 0 replies; 29+ messages in thread
From: Miquel RAYNAL @ 2017-10-19  7:36 UTC (permalink / raw)
  To: linux-arm-kernel

Hi Rob,

On Wed, 18 Oct 2017 08:29:07 -0500
Rob Herring <robh@kernel.org> wrote:

> On Wed, Oct 18, 2017 at 1:25 AM, Miquel RAYNAL
> <miquel.raynal@free-electrons.com> wrote:
> > Hi Rob,
> >
> > On Tue, 17 Oct 2017 17:00:22 -0500
> > Rob Herring <robh@kernel.org> wrote:
> >  
> >> On Fri, Oct 13, 2017 at 11:01:45AM +0200, Miquel Raynal wrote:  
> >> > Update the Device Tree binding documentation for the Marvell EBU
> >> > UART, in order to allow describing the extended UART IP block, in
> >> > addition to the already supported standard UART IP. This requires
> >> > adding a new compatible string, the introduction of a clocks
> >> > property, and extensions to the interrupts property.
> >> >
> >> > Signed-off-by: Miquel Raynal <miquel.raynal@free-electrons.com>
> >> > Reviewed-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
> >> > ---
> >> >  .../devicetree/bindings/serial/mvebu-uart.txt      | 49
> >> > +++++++++++++++++++--- 1 file changed, 44 insertions(+), 5
> >> > deletions(-)
> >> >
> >> > diff --git
> >> > a/Documentation/devicetree/bindings/serial/mvebu-uart.txt
> >> > b/Documentation/devicetree/bindings/serial/mvebu-uart.txt index
> >> > d37fabe17bd1..3df3a3fab4bb 100644 ---
> >> > a/Documentation/devicetree/bindings/serial/mvebu-uart.txt +++
> >> > b/Documentation/devicetree/bindings/serial/mvebu-uart.txt @@
> >> > -1,13 +1,52 @@ -* Marvell UART : Non standard UART used in some
> >> > of Marvell EBU SoCs (e.g., Armada-3700) +* Marvell UART : Non
> >> > standard UART used in some of Marvell EBU SoCs
> >> > +                 e.g., Armada-3700.
> >> >
> >> >  Required properties:
> >> > -- compatible: "marvell,armada-3700-uart"
> >> > +- compatible:
> >> > +    - "marvell,armada-3700-uart" for the standard variant of the
> >> > UART
> >> > +      (32 bytes FIFO, no DMA, level interrupts, 8-bit access to
> >> > the
> >> > +      FIFO, baudrate limited to 230400).
> >> > +    - "marvell,armada-3700-uart-ext" for the extended variant of
> >> > the
> >> > +      UART (128 bytes FIFO, DMA, front interrupts, 8-bit or
> >> > 32-bit
> >> > +      accesses to the FIFO, baudrate unlimited by the
> >> > dividers).  
> >>
> >> What do you call the next extended version?
> >> marvell,armada-3700-uart-ext-ext?  
> >
> > I don't know what you mean by "next extended version"?  
> 
> IP evolves on new chips with new features. Just trying to understand
> how you are

I think I misunderstood your initial question.

Indeed you are right, I did not think about the naming of a potential
next extended version of the extended IP, but I don't know how to
rename it otherwise than "-ext" to best fit what the "new" IP
does.

> 
> >> This is different versions of UART on the same chip?  
> >
> > Today in mainline there is support for the A3700 UART IP.
> > This series add support for another IP, based on the A3700, but with
> > extended features (explaining the -ext suffix).
> >
> > Can you precise what is bothering you?  
> 
> Is this different versions of UART IP on 1 chip or a new version of
> the UART IP on a new SoC? The latter should be a new compatible with
> the new SoC. The former case does happen some, but is not common. I'm
> just trying to understand which applies here.

Actually, both IP are available since the first version of the
Armada 3700 SoCs. There is no other implementation of these IPs yet. I
think we fall in the former case.

> 
> 
> >> >  - reg: offset and length of the register set for the device.
> >> > -- interrupts: device interrupt
> >> > +- clocks: UART reference clock used to derive the baudrate (only
> >> > +      mandatory with "marvell,armada-3700-uart-ext"
> >> > compatible).  
> >>
> >> How is this optional? The freq is fixed if not present? If so, what
> >> frequency?  
> >
> > The "clocks" property should not be optional at all but that is how
> > the bindings were handled before this series, so I can't tell now
> > that this property is mandatory as it would break compatibility
> > with older versions of the driver.  
> 
> Okay. I think it should be mandatory with a note how missing property
> is handled.

Sure.

> 
> > When no clock is provided, the frequency is fixed by the bootloader
> > and cannot be changed. There is no standard frequency for it but the
> > one chosen by the bootloader often is 115200 as the UART is usually
> > used as the serial console.
> >
> > Because the bootloader does only initialize the UART in use for the
> > serial console, the clock is mandatory when using another port or it
> > will not work at all.  

Thank you,
Miqu?l


-- 
Miquel Raynal, Free Electrons
Embedded Linux and Kernel engineering
http://free-electrons.com

^ permalink raw reply	[flat|nested] 29+ messages in thread

* [PATCH v2 13/16] arm64: dts: marvell: armada-37xx: add UART clock
  2017-10-13  9:01 ` [PATCH v2 13/16] arm64: dts: marvell: armada-37xx: add UART clock Miquel Raynal
@ 2017-10-30 15:45   ` Gregory CLEMENT
  0 siblings, 0 replies; 29+ messages in thread
From: Gregory CLEMENT @ 2017-10-30 15:45 UTC (permalink / raw)
  To: linux-arm-kernel

Hi Miquel,
 
 On ven., oct. 13 2017, Miquel Raynal <miquel.raynal@free-electrons.com> wrote:

> Add the missing clock property to armada-3700 UART node.
>
> This clock will be used to derive the prescaler value to comply with
> the requested baudrate.
>
> Signed-off-by: Miquel Raynal <miquel.raynal@free-electrons.com>
> Acked-by: Gregory CLEMENT <gregory.clement@free-electrons.com>

Applied on mvebu/dt64

Thanks,

Gregory

> ---
>  arch/arm64/boot/dts/marvell/armada-37xx.dtsi | 1 +
>  1 file changed, 1 insertion(+)
>
> diff --git a/arch/arm64/boot/dts/marvell/armada-37xx.dtsi b/arch/arm64/boot/dts/marvell/armada-37xx.dtsi
> index b554cdaf5e53..a36d667f770e 100644
> --- a/arch/arm64/boot/dts/marvell/armada-37xx.dtsi
> +++ b/arch/arm64/boot/dts/marvell/armada-37xx.dtsi
> @@ -135,6 +135,7 @@
>  			uart0: serial at 12000 {
>  				compatible = "marvell,armada-3700-uart";
>  				reg = <0x12000 0x200>;
> +				clocks = <&xtalclk>;
>  				interrupts = <GIC_SPI 11 IRQ_TYPE_LEVEL_HIGH>;
>  				status = "disabled";
>  			};
> -- 
> 2.11.0
>
>
> _______________________________________________
> linux-arm-kernel mailing list
> linux-arm-kernel at lists.infradead.org
> http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

-- 
Gregory Clement, Free Electrons
Kernel, drivers, real-time and embedded Linux
development, consulting, training and support.
http://free-electrons.com

^ permalink raw reply	[flat|nested] 29+ messages in thread

* [PATCH v2 14/16] arm64: dts: marvell: armada-37xx: add second UART port
  2017-10-13  9:01 ` [PATCH v2 14/16] arm64: dts: marvell: armada-37xx: add second UART port Miquel Raynal
@ 2017-10-30 15:45   ` Gregory CLEMENT
  0 siblings, 0 replies; 29+ messages in thread
From: Gregory CLEMENT @ 2017-10-30 15:45 UTC (permalink / raw)
  To: linux-arm-kernel

Hi Miquel,
 
 On ven., oct. 13 2017, Miquel Raynal <miquel.raynal@free-electrons.com> wrote:

> Add a node in Armada 37xx DTSI file for the second UART, with a
> different compatible due to its extended IP which has some
> differences with the first UART already in place.
>
> Make use of this commit to also fully describe the first port and
> use the same clear and named interrupt bindings for both ports.
>
> The standard UART (UART0) uses level-interrupts while the extended
> UART (UART1) uses edge-triggered interrupts.
>
> Signed-off-by: Miquel Raynal <miquel.raynal@free-electrons.com>
> Acked-by: Gregory CLEMENT <gregory.clement@free-electrons.com>

Applied on mvebu/dt64

Thanks,

Gregory

> ---
>  arch/arm64/boot/dts/marvell/armada-37xx.dtsi | 18 +++++++++++++++++-
>  1 file changed, 17 insertions(+), 1 deletion(-)
>
> diff --git a/arch/arm64/boot/dts/marvell/armada-37xx.dtsi b/arch/arm64/boot/dts/marvell/armada-37xx.dtsi
> index a36d667f770e..72b68f23c001 100644
> --- a/arch/arm64/boot/dts/marvell/armada-37xx.dtsi
> +++ b/arch/arm64/boot/dts/marvell/armada-37xx.dtsi
> @@ -55,6 +55,7 @@
>  
>  	aliases {
>  		serial0 = &uart0;
> +		serial1 = &uart1;
>  	};
>  
>  	cpus {
> @@ -136,7 +137,22 @@
>  				compatible = "marvell,armada-3700-uart";
>  				reg = <0x12000 0x200>;
>  				clocks = <&xtalclk>;
> -				interrupts = <GIC_SPI 11 IRQ_TYPE_LEVEL_HIGH>;
> +				interrupts =
> +				<GIC_SPI 11 IRQ_TYPE_LEVEL_HIGH>,
> +				<GIC_SPI 12 IRQ_TYPE_LEVEL_HIGH>,
> +				<GIC_SPI 13 IRQ_TYPE_LEVEL_HIGH>;
> +				interrupt-names = "uart-sum", "uart-tx", "uart-rx";
> +				status = "disabled";
> +			};
> +
> +			uart1: serial at 12200 {
> +				compatible = "marvell,armada-3700-uart-ext";
> +				reg = <0x12200 0x30>;
> +				clocks = <&xtalclk>;
> +				interrupts =
> +				<GIC_SPI 30 IRQ_TYPE_EDGE_RISING>,
> +				<GIC_SPI 31 IRQ_TYPE_EDGE_RISING>;
> +				interrupt-names = "uart-tx", "uart-rx";
>  				status = "disabled";
>  			};
>  
> -- 
> 2.11.0
>
>
> _______________________________________________
> linux-arm-kernel mailing list
> linux-arm-kernel at lists.infradead.org
> http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

-- 
Gregory Clement, Free Electrons
Kernel, drivers, real-time and embedded Linux
development, consulting, training and support.
http://free-electrons.com

^ permalink raw reply	[flat|nested] 29+ messages in thread

* [PATCH v2 15/16] arm64: dts: marvell: armada-3720-db: enable second UART port
  2017-10-13  9:01 ` [PATCH v2 15/16] arm64: dts: marvell: armada-3720-db: enable " Miquel Raynal
@ 2017-10-30 15:46   ` Gregory CLEMENT
  0 siblings, 0 replies; 29+ messages in thread
From: Gregory CLEMENT @ 2017-10-30 15:46 UTC (permalink / raw)
  To: linux-arm-kernel

Hi Miquel,
 
 On ven., oct. 13 2017, Miquel Raynal <miquel.raynal@free-electrons.com> wrote:

> Enable Armada-3720-DB second UART port by adding the corresponding
> device tree node in the board DTS and enabling it.
>
> Signed-off-by: Miquel Raynal <miquel.raynal@free-electrons.com>
> Acked-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
> ---

Applied on mvebu/dt64

Thanks,

Gregory

>  arch/arm64/boot/dts/marvell/armada-3720-db.dts | 9 ++++++++-
>  1 file changed, 8 insertions(+), 1 deletion(-)
>
> diff --git a/arch/arm64/boot/dts/marvell/armada-3720-db.dts b/arch/arm64/boot/dts/marvell/armada-3720-db.dts
> index 9df0f06ce607..15713c19b3d0 100644
> --- a/arch/arm64/boot/dts/marvell/armada-3720-db.dts
> +++ b/arch/arm64/boot/dts/marvell/armada-3720-db.dts
> @@ -216,7 +216,7 @@
>  
>  /*
>   * Exported on the micro USB connector CON30(V2.0)/CON32(V1.4) through
> - * an FTDI
> + * an FTDI (also on CON24(V2.0)/CON26(V1.4)).
>   */
>  &uart0 {
>  	pinctrl-names = "default";
> @@ -224,6 +224,13 @@
>  	status = "okay";
>  };
>  
> +/* CON26(V2.0)/CON28(V1.4) */
> +&uart1 {
> +	pinctrl-names = "default";
> +	pinctrl-0 = <&uart2_pins>;
> +	status = "okay";
> +};
> +
>  /* CON27(V2.0)/CON29(V1.4) */
>  &usb2 {
>  	status = "okay";
> -- 
> 2.11.0
>
>
> _______________________________________________
> linux-arm-kernel mailing list
> linux-arm-kernel at lists.infradead.org
> http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

-- 
Gregory Clement, Free Electrons
Kernel, drivers, real-time and embedded Linux
development, consulting, training and support.
http://free-electrons.com

^ permalink raw reply	[flat|nested] 29+ messages in thread

* [PATCH v2 16/16] arm64: dts: marvell: armada-3720-espressobin: fill UART nodes
  2017-10-13  9:02 ` [PATCH v2 16/16] arm64: dts: marvell: armada-3720-espressobin: fill UART nodes Miquel Raynal
@ 2017-10-30 15:46   ` Gregory CLEMENT
  0 siblings, 0 replies; 29+ messages in thread
From: Gregory CLEMENT @ 2017-10-30 15:46 UTC (permalink / raw)
  To: linux-arm-kernel

Hi Miquel,
 
 On ven., oct. 13 2017, Miquel Raynal <miquel.raynal@free-electrons.com> wrote:

> Fill ESPRESSObin uart0 node with pinctrl information like in the
> Armada-3720-DB device tree (which uses the same node).
>
> Also explain how to enable the second UART port available on the
> headers. This second port is not enabled by default because both
> headers are dedicated to expose general purpose pins and remapping
> some of them to use the second UART would break existing users.
>
> Suggested-by: L?szl? ?SHIN <laszlo@ashin.hu>
> Signed-off-by: Miquel Raynal <miquel.raynal@free-electrons.com>

Applied on mvebu/dt64

Thanks,

Gregory

> ---
>
> Changes since v1: comment about UART1 node.
>
>  arch/arm64/boot/dts/marvell/armada-3720-espressobin.dts | 12 ++++++++++++
>  1 file changed, 12 insertions(+)
>
> diff --git a/arch/arm64/boot/dts/marvell/armada-3720-espressobin.dts b/arch/arm64/boot/dts/marvell/armada-3720-espressobin.dts
> index 2ce52ba74f73..bdfb5553ddb5 100644
> --- a/arch/arm64/boot/dts/marvell/armada-3720-espressobin.dts
> +++ b/arch/arm64/boot/dts/marvell/armada-3720-espressobin.dts
> @@ -98,9 +98,21 @@
>  
>  /* Exported on the micro USB connector J5 through an FTDI */
>  &uart0 {
> +	pinctrl-names = "default";
> +	pinctrl-0 = <&uart1_pins>;
>  	status = "okay";
>  };
>  
> +/*
> + * Connector J17 and J18 expose a number of different features. Some pins are
> + * multiplexed. This is the case for instance for the following features:
> + * - UART1 (pin 24 = RX, pin 26 = TX). See armada-3720-db.dts for an example of
> + *   how to enable it. Beware that the signals are 1.8V TTL.
> + * - I2C
> + * - SPI
> + * - MMC
> + */
> +
>  /* J7 */
>  &usb3 {
>  	status = "okay";
> -- 
> 2.11.0
>
>
> _______________________________________________
> linux-arm-kernel mailing list
> linux-arm-kernel at lists.infradead.org
> http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

-- 
Gregory Clement, Free Electrons
Kernel, drivers, real-time and embedded Linux
development, consulting, training and support.
http://free-electrons.com

^ permalink raw reply	[flat|nested] 29+ messages in thread

end of thread, other threads:[~2017-10-30 15:46 UTC | newest]

Thread overview: 29+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2017-10-13  9:01 [PATCH v2 00/16] Support armada-37xx second UART port Miquel Raynal
2017-10-13  9:01 ` [PATCH v2 01/16] dt-bindings: mvebu-uart: update documentation with extended UART Miquel Raynal
2017-10-17 22:00   ` Rob Herring
2017-10-18  6:25     ` Miquel RAYNAL
2017-10-18 13:29       ` Rob Herring
2017-10-19  7:36         ` Miquel RAYNAL
2017-10-13  9:01 ` [PATCH v2 02/16] pinctrl: dt-bindings: Fix A37xx uart2 group name Miquel Raynal
2017-10-16 11:56   ` Linus Walleij
2017-10-13  9:01 ` [PATCH v2 03/16] serial: mvebu-uart: use driver name when requesting an interrupt Miquel Raynal
2017-10-13  9:01 ` [PATCH v2 04/16] serial: mvebu-uart: support probe of multiple ports Miquel Raynal
2017-10-13  9:40   ` Gregory CLEMENT
2017-10-13 11:17     ` Miquel RAYNAL
2017-10-13 11:22       ` Gregory CLEMENT
2017-10-13  9:01 ` [PATCH v2 05/16] serial: mvebu-uart: use a generic way to access the registers Miquel Raynal
2017-10-13  9:01 ` [PATCH v2 06/16] serial: mvebu-uart: add soft reset at probe Miquel Raynal
2017-10-13  9:01 ` [PATCH v2 07/16] serial: mvebu-uart: add function to change baudrate Miquel Raynal
2017-10-13  9:01 ` [PATCH v2 08/16] serial: mvebu-uart: clear state register before IRQ request Miquel Raynal
2017-10-13  9:01 ` [PATCH v2 09/16] serial: mvebu-uart: add TX interrupt trigger for pulse interrupts Miquel Raynal
2017-10-13  9:01 ` [PATCH v2 10/16] serial: mvebu-uart: dissociate RX and TX interrupts Miquel Raynal
2017-10-13  9:01 ` [PATCH v2 11/16] serial: mvebu-uart: augment the maximum number of ports Miquel Raynal
2017-10-13  9:01 ` [PATCH v2 12/16] serial: mvebu-uart: support extended port registers layout Miquel Raynal
2017-10-13  9:01 ` [PATCH v2 13/16] arm64: dts: marvell: armada-37xx: add UART clock Miquel Raynal
2017-10-30 15:45   ` Gregory CLEMENT
2017-10-13  9:01 ` [PATCH v2 14/16] arm64: dts: marvell: armada-37xx: add second UART port Miquel Raynal
2017-10-30 15:45   ` Gregory CLEMENT
2017-10-13  9:01 ` [PATCH v2 15/16] arm64: dts: marvell: armada-3720-db: enable " Miquel Raynal
2017-10-30 15:46   ` Gregory CLEMENT
2017-10-13  9:02 ` [PATCH v2 16/16] arm64: dts: marvell: armada-3720-espressobin: fill UART nodes Miquel Raynal
2017-10-30 15:46   ` Gregory CLEMENT

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