diff mbox series

[V2] serial: 8250_tegra: Create Tegra specific 8250 driver

Message ID 20200124145940.23194-1-jonathanh@nvidia.com
State Superseded
Headers show
Series [V2] serial: 8250_tegra: Create Tegra specific 8250 driver | expand

Commit Message

Jon Hunter Jan. 24, 2020, 2:59 p.m. UTC 
From: Jeff Brasen <jbrasen@nvidia.com>

To support booting NVIDIA Tegra platforms with either Device-Tree or
ACPI, create a Tegra specific 8250 serial driver that supports both
firmware types. Another benefit from doing this, is that the Tegra
specific codec in the generic Open Firmware 8250 driver can now be
removed.

Signed-off-by: Jeff Brasen <jbrasen@nvidia.com>
Signed-off-by: Jon Hunter <jonathanh@nvidia.com>
---

Changes since V1:
- Added support for COMPILE_TEST

 drivers/tty/serial/8250/8250_of.c    |  28 ----
 drivers/tty/serial/8250/8250_tegra.c | 197 +++++++++++++++++++++++++++
 drivers/tty/serial/8250/Kconfig      |   9 ++
 drivers/tty/serial/8250/Makefile     |   1 +
 4 files changed, 207 insertions(+), 28 deletions(-)
 create mode 100644 drivers/tty/serial/8250/8250_tegra.c

Comments

kernel test robot Jan. 25, 2020, 4:54 p.m. UTC | #1 
Hi Jon,

Thank you for the patch! Yet something to improve:

[auto build test ERROR on tty/tty-testing]
[also build test ERROR on usb/usb-testing v5.5-rc7 next-20200124]
[if your patch is applied to the wrong git tree, please drop us a note to help
improve the system. BTW, we also suggest to use '--base' option to specify the
base tree in git format-patch, please see https://stackoverflow.com/a/37406982]

url:    https://github.com/0day-ci/linux/commits/Jon-Hunter/serial-8250_tegra-Create-Tegra-specific-8250-driver/20200125-195201
base:   https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty.git tty-testing
config: arm-defconfig (attached as .config)
compiler: arm-linux-gnueabi-gcc (GCC) 7.5.0
reproduce:
        wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        # save the attached .config to linux build tree
        GCC_VERSION=7.5.0 make.cross ARCH=arm 

If you fix the issue, kindly add following tag
Reported-by: kbuild test robot <lkp@intel.com>

All error/warnings (new ones prefixed by >>):

   drivers/tty/serial/8250/8250_tegra.c: In function 'tegra_uart_probe':
>> drivers/tty/serial/8250/8250_tegra.c:80:18: error: implicit declaration of function 'devm_ioremap'; did you mean 'ioremap'? [-Werror=implicit-function-declaration]
     port->membase = devm_ioremap(&pdev->dev, res->start,
                     ^~~~~~~~~~~~
                     ioremap
>> drivers/tty/serial/8250/8250_tegra.c:80:16: warning: assignment makes pointer from integer without a cast [-Wint-conversion]
     port->membase = devm_ioremap(&pdev->dev, res->start,
                   ^
   cc1: some warnings being treated as errors

vim +80 drivers/tty/serial/8250/8250_tegra.c

    39	
    40	static int tegra_uart_probe(struct platform_device *pdev)
    41	{
    42		struct uart_8250_port port8250;
    43		struct tegra_uart *uart;
    44		struct uart_port *port;
    45		struct resource *res;
    46		int ret;
    47	
    48		uart = devm_kzalloc(&pdev->dev, sizeof(*uart), GFP_KERNEL);
    49		if (!uart)
    50			return -ENOMEM;
    51	
    52		memset(&port8250, 0, sizeof(port8250));
    53	
    54		port = &port8250.port;
    55		spin_lock_init(&port->lock);
    56	
    57		port->flags = UPF_SHARE_IRQ | UPF_BOOT_AUTOCONF | UPF_FIXED_PORT |
    58			      UPF_FIXED_TYPE;
    59		port->iotype = UPIO_MEM32;
    60		port->regshift = 2;
    61		port->type = PORT_TEGRA;
    62		port->irqflags |= IRQF_SHARED;
    63		port->dev = &pdev->dev;
    64		port->handle_break = tegra_uart_handle_break;
    65	
    66		ret = of_alias_get_id(pdev->dev.of_node, "serial");
    67		if (ret >= 0)
    68			port->line = ret;
    69	
    70		ret = platform_get_irq(pdev, 0);
    71		if (ret < 0)
    72			return ret;
    73	
    74		port->irq = ret;
    75	
    76		res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
    77		if (!res)
    78			return -ENODEV;
    79	
  > 80		port->membase = devm_ioremap(&pdev->dev, res->start,
    81					     resource_size(res));
    82		if (!port->membase)
    83			return -ENOMEM;
    84	
    85		port->mapbase = res->start;
    86		port->mapsize = resource_size(res);
    87	
    88		uart->rst = devm_reset_control_get_optional_shared(&pdev->dev, NULL);
    89		if (IS_ERR(uart->rst))
    90			return PTR_ERR(uart->rst);
    91	
    92		if (device_property_read_u32(&pdev->dev, "clock-frequency",
    93					     &port->uartclk)) {
    94			uart->clk = devm_clk_get(&pdev->dev, NULL);
    95			if (IS_ERR(uart->clk)) {
    96				dev_err(&pdev->dev, "failed to get clock!\n");
    97				return -ENODEV;
    98			}
    99	
   100			ret = clk_prepare_enable(uart->clk);
   101			if (ret < 0)
   102				return ret;
   103	
   104			port->uartclk = clk_get_rate(uart->clk);
   105		}
   106	
   107		ret = reset_control_deassert(uart->rst);
   108		if (ret)
   109			goto err_clkdisable;
   110	
   111		ret = serial8250_register_8250_port(&port8250);
   112		if (ret < 0)
   113			goto err_clkdisable;
   114	
   115		platform_set_drvdata(pdev, uart);
   116		uart->line = ret;
   117	
   118		return 0;
   119	
   120	err_clkdisable:
   121		clk_disable_unprepare(uart->clk);
   122	
   123		return ret;
   124	}
   125	

---
0-DAY kernel test infrastructure                 Open Source Technology Center
https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org Intel Corporation
kernel test robot Jan. 25, 2020, 6:37 p.m. UTC | #2 
Hi Jon,

Thank you for the patch! Yet something to improve:

[auto build test ERROR on tty/tty-testing]
[also build test ERROR on usb/usb-testing v5.5-rc7 next-20200124]
[if your patch is applied to the wrong git tree, please drop us a note to help
improve the system. BTW, we also suggest to use '--base' option to specify the
base tree in git format-patch, please see https://stackoverflow.com/a/37406982]

url:    https://github.com/0day-ci/linux/commits/Jon-Hunter/serial-8250_tegra-Create-Tegra-specific-8250-driver/20200125-195201
base:   https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty.git tty-testing
config: m68k-allmodconfig (attached as .config)
compiler: m68k-linux-gcc (GCC) 7.5.0
reproduce:
        wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        # save the attached .config to linux build tree
        GCC_VERSION=7.5.0 make.cross ARCH=m68k 

If you fix the issue, kindly add following tag
Reported-by: kbuild test robot <lkp@intel.com>

All errors (new ones prefixed by >>):

   drivers/tty/serial/8250/8250_tegra.c: In function 'tegra_uart_probe':
>> drivers/tty/serial/8250/8250_tegra.c:80:18: error: implicit declaration of function 'devm_ioremap'; did you mean '__ioremap'? [-Werror=implicit-function-declaration]
     port->membase = devm_ioremap(&pdev->dev, res->start,
                     ^~~~~~~~~~~~
                     __ioremap
   drivers/tty/serial/8250/8250_tegra.c:80:16: warning: assignment makes pointer from integer without a cast [-Wint-conversion]
     port->membase = devm_ioremap(&pdev->dev, res->start,
                   ^
   cc1: some warnings being treated as errors

vim +80 drivers/tty/serial/8250/8250_tegra.c

    39	
    40	static int tegra_uart_probe(struct platform_device *pdev)
    41	{
    42		struct uart_8250_port port8250;
    43		struct tegra_uart *uart;
    44		struct uart_port *port;
    45		struct resource *res;
    46		int ret;
    47	
    48		uart = devm_kzalloc(&pdev->dev, sizeof(*uart), GFP_KERNEL);
    49		if (!uart)
    50			return -ENOMEM;
    51	
    52		memset(&port8250, 0, sizeof(port8250));
    53	
    54		port = &port8250.port;
    55		spin_lock_init(&port->lock);
    56	
    57		port->flags = UPF_SHARE_IRQ | UPF_BOOT_AUTOCONF | UPF_FIXED_PORT |
    58			      UPF_FIXED_TYPE;
    59		port->iotype = UPIO_MEM32;
    60		port->regshift = 2;
    61		port->type = PORT_TEGRA;
    62		port->irqflags |= IRQF_SHARED;
    63		port->dev = &pdev->dev;
    64		port->handle_break = tegra_uart_handle_break;
    65	
    66		ret = of_alias_get_id(pdev->dev.of_node, "serial");
    67		if (ret >= 0)
    68			port->line = ret;
    69	
    70		ret = platform_get_irq(pdev, 0);
    71		if (ret < 0)
    72			return ret;
    73	
    74		port->irq = ret;
    75	
    76		res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
    77		if (!res)
    78			return -ENODEV;
    79	
  > 80		port->membase = devm_ioremap(&pdev->dev, res->start,
    81					     resource_size(res));
    82		if (!port->membase)
    83			return -ENOMEM;
    84	
    85		port->mapbase = res->start;
    86		port->mapsize = resource_size(res);
    87	
    88		uart->rst = devm_reset_control_get_optional_shared(&pdev->dev, NULL);
    89		if (IS_ERR(uart->rst))
    90			return PTR_ERR(uart->rst);
    91	
    92		if (device_property_read_u32(&pdev->dev, "clock-frequency",
    93					     &port->uartclk)) {
    94			uart->clk = devm_clk_get(&pdev->dev, NULL);
    95			if (IS_ERR(uart->clk)) {
    96				dev_err(&pdev->dev, "failed to get clock!\n");
    97				return -ENODEV;
    98			}
    99	
   100			ret = clk_prepare_enable(uart->clk);
   101			if (ret < 0)
   102				return ret;
   103	
   104			port->uartclk = clk_get_rate(uart->clk);
   105		}
   106	
   107		ret = reset_control_deassert(uart->rst);
   108		if (ret)
   109			goto err_clkdisable;
   110	
   111		ret = serial8250_register_8250_port(&port8250);
   112		if (ret < 0)
   113			goto err_clkdisable;
   114	
   115		platform_set_drvdata(pdev, uart);
   116		uart->line = ret;
   117	
   118		return 0;
   119	
   120	err_clkdisable:
   121		clk_disable_unprepare(uart->clk);
   122	
   123		return ret;
   124	}
   125	

---
0-DAY kernel test infrastructure                 Open Source Technology Center
https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org Intel Corporation
diff mbox series

Patch

diff --git a/drivers/tty/serial/8250/8250_of.c b/drivers/tty/serial/8250/8250_of.c
index 531ad67395e0..5e45cf8dbc6e 100644
--- a/drivers/tty/serial/8250/8250_of.c
+++ b/drivers/tty/serial/8250/8250_of.c
@@ -7,7 +7,6 @@ 
 #include <linux/console.h>
 #include <linux/module.h>
 #include <linux/slab.h>
-#include <linux/delay.h>
 #include <linux/serial_core.h>
 #include <linux/serial_reg.h>
 #include <linux/of_address.h>
@@ -26,28 +25,6 @@  struct of_serial_info {
 	int line;
 };
 
-#ifdef CONFIG_ARCH_TEGRA
-static void tegra_serial_handle_break(struct uart_port *p)
-{
-	unsigned int status, tmout = 10000;
-
-	do {
-		status = p->serial_in(p, UART_LSR);
-		if (status & (UART_LSR_FIFOE | UART_LSR_BRK_ERROR_BITS))
-			status = p->serial_in(p, UART_RX);
-		else
-			break;
-		if (--tmout == 0)
-			break;
-		udelay(1);
-	} while (1);
-}
-#else
-static inline void tegra_serial_handle_break(struct uart_port *port)
-{
-}
-#endif
-
 static int of_8250_rs485_config(struct uart_port *port,
 				  struct serial_rs485 *rs485)
 {
@@ -211,10 +188,6 @@  static int of_platform_serial_setup(struct platform_device *ofdev,
 	port->rs485_config = of_8250_rs485_config;
 
 	switch (type) {
-	case PORT_TEGRA:
-		port->handle_break = tegra_serial_handle_break;
-		break;
-
 	case PORT_RT2880:
 		port->iotype = UPIO_AU;
 		break;
@@ -359,7 +332,6 @@  static const struct of_device_id of_platform_serial_table[] = {
 	{ .compatible = "ns16550",  .data = (void *)PORT_16550, },
 	{ .compatible = "ns16750",  .data = (void *)PORT_16750, },
 	{ .compatible = "ns16850",  .data = (void *)PORT_16850, },
-	{ .compatible = "nvidia,tegra20-uart", .data = (void *)PORT_TEGRA, },
 	{ .compatible = "nxp,lpc3220-uart", .data = (void *)PORT_LPC3220, },
 	{ .compatible = "ralink,rt2880-uart", .data = (void *)PORT_RT2880, },
 	{ .compatible = "intel,xscale-uart", .data = (void *)PORT_XSCALE, },
diff --git a/drivers/tty/serial/8250/8250_tegra.c b/drivers/tty/serial/8250/8250_tegra.c
new file mode 100644
index 000000000000..e639ce833132
--- /dev/null
+++ b/drivers/tty/serial/8250/8250_tegra.c
@@ -0,0 +1,197 @@ 
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ *  Serial Port driver for Tegra devices
+ *
+ *  Copyright (c) 2020, NVIDIA CORPORATION. All rights reserved.
+ */
+
+#include <linux/acpi.h>
+#include <linux/clk.h>
+#include <linux/console.h>
+#include <linux/delay.h>
+#include <linux/module.h>
+#include <linux/reset.h>
+#include <linux/slab.h>
+
+#include "8250.h"
+
+struct tegra_uart {
+	struct clk *clk;
+	struct reset_control *rst;
+	int line;
+};
+
+static void tegra_uart_handle_break(struct uart_port *p)
+{
+	unsigned int status, tmout = 10000;
+
+	do {
+		status = p->serial_in(p, UART_LSR);
+		if (status & (UART_LSR_FIFOE | UART_LSR_BRK_ERROR_BITS))
+			status = p->serial_in(p, UART_RX);
+		else
+			break;
+		if (--tmout == 0)
+			break;
+		udelay(1);
+	} while (1);
+}
+
+static int tegra_uart_probe(struct platform_device *pdev)
+{
+	struct uart_8250_port port8250;
+	struct tegra_uart *uart;
+	struct uart_port *port;
+	struct resource *res;
+	int ret;
+
+	uart = devm_kzalloc(&pdev->dev, sizeof(*uart), GFP_KERNEL);
+	if (!uart)
+		return -ENOMEM;
+
+	memset(&port8250, 0, sizeof(port8250));
+
+	port = &port8250.port;
+	spin_lock_init(&port->lock);
+
+	port->flags = UPF_SHARE_IRQ | UPF_BOOT_AUTOCONF | UPF_FIXED_PORT |
+		      UPF_FIXED_TYPE;
+	port->iotype = UPIO_MEM32;
+	port->regshift = 2;
+	port->type = PORT_TEGRA;
+	port->irqflags |= IRQF_SHARED;
+	port->dev = &pdev->dev;
+	port->handle_break = tegra_uart_handle_break;
+
+	ret = of_alias_get_id(pdev->dev.of_node, "serial");
+	if (ret >= 0)
+		port->line = ret;
+
+	ret = platform_get_irq(pdev, 0);
+	if (ret < 0)
+		return ret;
+
+	port->irq = ret;
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (!res)
+		return -ENODEV;
+
+	port->membase = devm_ioremap(&pdev->dev, res->start,
+				     resource_size(res));
+	if (!port->membase)
+		return -ENOMEM;
+
+	port->mapbase = res->start;
+	port->mapsize = resource_size(res);
+
+	uart->rst = devm_reset_control_get_optional_shared(&pdev->dev, NULL);
+	if (IS_ERR(uart->rst))
+		return PTR_ERR(uart->rst);
+
+	if (device_property_read_u32(&pdev->dev, "clock-frequency",
+				     &port->uartclk)) {
+		uart->clk = devm_clk_get(&pdev->dev, NULL);
+		if (IS_ERR(uart->clk)) {
+			dev_err(&pdev->dev, "failed to get clock!\n");
+			return -ENODEV;
+		}
+
+		ret = clk_prepare_enable(uart->clk);
+		if (ret < 0)
+			return ret;
+
+		port->uartclk = clk_get_rate(uart->clk);
+	}
+
+	ret = reset_control_deassert(uart->rst);
+	if (ret)
+		goto err_clkdisable;
+
+	ret = serial8250_register_8250_port(&port8250);
+	if (ret < 0)
+		goto err_clkdisable;
+
+	platform_set_drvdata(pdev, uart);
+	uart->line = ret;
+
+	return 0;
+
+err_clkdisable:
+	clk_disable_unprepare(uart->clk);
+
+	return ret;
+}
+
+static int tegra_uart_remove(struct platform_device *pdev)
+{
+	struct tegra_uart *uart = platform_get_drvdata(pdev);
+
+	serial8250_unregister_port(uart->line);
+	reset_control_assert(uart->rst);
+	clk_disable_unprepare(uart->clk);
+
+	return 0;
+}
+
+#ifdef CONFIG_PM_SLEEP
+static int tegra_uart_suspend(struct device *dev)
+{
+	struct tegra_uart *uart = dev_get_drvdata(dev);
+	struct uart_8250_port *port8250 = serial8250_get_port(uart->line);
+	struct uart_port *port = &port8250->port;
+
+	serial8250_suspend_port(uart->line);
+
+	if (!uart_console(port) || console_suspend_enabled)
+		clk_disable_unprepare(uart->clk);
+
+	return 0;
+}
+
+static int tegra_uart_resume(struct device *dev)
+{
+	struct tegra_uart *uart = dev_get_drvdata(dev);
+	struct uart_8250_port *port8250 = serial8250_get_port(uart->line);
+	struct uart_port *port = &port8250->port;
+
+	if (!uart_console(port) || console_suspend_enabled)
+		clk_prepare_enable(uart->clk);
+
+	serial8250_resume_port(uart->line);
+
+	return 0;
+}
+#endif
+
+static SIMPLE_DEV_PM_OPS(tegra_uart_pm_ops, tegra_uart_suspend,
+			 tegra_uart_resume);
+
+static const struct of_device_id tegra_uart_of_match[] = {
+	{ .compatible = "nvidia,tegra20-uart", },
+	{ },
+};
+MODULE_DEVICE_TABLE(of, tegra_uart_of_match);
+
+static const struct acpi_device_id tegra_uart_acpi_match[] = {
+	{ "NVDA0100", 0 },
+	{ },
+};
+MODULE_DEVICE_TABLE(acpi, tegra_uart_acpi_match);
+
+static struct platform_driver tegra_uart_driver = {
+	.driver = {
+		.name = "tegra-uart",
+		.pm = &tegra_uart_pm_ops,
+		.of_match_table = tegra_uart_of_match,
+		.acpi_match_table = ACPI_PTR(tegra_uart_acpi_match),
+	},
+	.probe = tegra_uart_probe,
+	.remove = tegra_uart_remove,
+};
+
+module_platform_driver(tegra_uart_driver);
+
+MODULE_AUTHOR("Jeff Brasen <jbrasen@nvidia.com>");
+MODULE_DESCRIPTION("NVIDIA Tegra 8250 Driver");
+MODULE_LICENSE("GPL v2");
diff --git a/drivers/tty/serial/8250/Kconfig b/drivers/tty/serial/8250/Kconfig
index f16824bbb573..af0688156dd0 100644
--- a/drivers/tty/serial/8250/Kconfig
+++ b/drivers/tty/serial/8250/Kconfig
@@ -500,6 +500,15 @@  config SERIAL_8250_PXA
 	  applicable to both devicetree and legacy boards, and early console is
 	  part of its support.
 
+config SERIAL_8250_TEGRA
+	tristate "8250 support for Tegra serial ports"
+	default SERIAL_8250
+	depends on SERIAL_8250
+	depends on ARCH_TEGRA || COMPILE_TEST
+	help
+	  Select this option if you have machine with an NVIDIA Tegra SoC and
+	  wish to enable 8250 serial driver for the Tegra serial interfaces.
+
 config SERIAL_OF_PLATFORM
 	tristate "Devicetree based probing for 8250 ports"
 	depends on SERIAL_8250 && OF
diff --git a/drivers/tty/serial/8250/Makefile b/drivers/tty/serial/8250/Makefile
index 51a6079d3f1f..a8bfb654d490 100644
--- a/drivers/tty/serial/8250/Makefile
+++ b/drivers/tty/serial/8250/Makefile
@@ -37,6 +37,7 @@  obj-$(CONFIG_SERIAL_8250_INGENIC)	+= 8250_ingenic.o
 obj-$(CONFIG_SERIAL_8250_LPSS)		+= 8250_lpss.o
 obj-$(CONFIG_SERIAL_8250_MID)		+= 8250_mid.o
 obj-$(CONFIG_SERIAL_8250_PXA)		+= 8250_pxa.o
+obj-$(CONFIG_SERIAL_8250_TEGRA)		+= 8250_tegra.o
 obj-$(CONFIG_SERIAL_OF_PLATFORM)	+= 8250_of.o
 
 CFLAGS_8250_ingenic.o += -I$(srctree)/scripts/dtc/libfdt