From: Jeff Brasen <[email protected]>
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 <[email protected]>
Signed-off-by: Jon Hunter <[email protected]>
---
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
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 <[email protected]>");
+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
--
2.17.1
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 <[email protected]>
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/[email protected] Intel Corporation
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 <[email protected]>
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/[email protected] Intel Corporation