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[PATCH v4] drivers/char: rename arm-uart.c to uart-init.c

From: Oleksii Kurochko <oleksii.kurochko@xxxxxxxxx>

Date: Tue, 19 Nov 2024 15:55:32 +0100

Cc: Oleksii Kurochko <oleksii.kurochko@xxxxxxxxx>, Andrew Cooper <andrew.cooper3@xxxxxxxxxx>, Jan Beulich <jbeulich@xxxxxxxx>, Julien Grall <julien@xxxxxxx>, Stefano Stabellini <sstabellini@xxxxxxxxxx>, Bertrand Marquis <bertrand.marquis@xxxxxxx>, Michal Orzel <michal.orzel@xxxxxxx>, Volodymyr Babchuk <Volodymyr_Babchuk@xxxxxxxx>

Delivery-date: Tue, 19 Nov 2024 14:55:52 +0000

List-id: Xen developer discussion <xen-devel.lists.xenproject.org>

Rename the file containing uart_init() to enable reuse across other architectures that utilize device trees or SPCR tables to locate UART information. After locating UART data, {acpi}_device_init() is called to initialize the UART. arm_uart_init() is renamed to uart_init() to be reused by other architectures. A new configuration option, CONFIG_GENERIC_UART_INIT, is introduced, currently available only for Arm. Enabling CONFIG_UART_INIT on additional architectures will require additional functionality, such as device tree mapping and unflattening, etc. arm-uart.c is removed from "ARM (W/ VIRTUALIZATION EXTENSIONS) ARCHITECTURE" section in the MAINTAINERS file, as it is no longer Arm-specific and can now be maintained by maintainers of other architectures. Use GENERIC_UART_INIT for CONFIG_ARM by adding `select GENERIC_UART_INIT` to CONFIG_ARM. Signed-off-by: Oleksii Kurochko <oleksii.kurochko@xxxxxxxxx> --- Changes in V4: - Rename UART_INIT config to GENERIC_UART_INIT. - Update defintion of GENERIC_UART_INIT config in char/Kconfig: drop prompt, help and `depends on` as CONFIG_GENERIC_UART_INIT isn't expected to be disabled/enabled by user thereby make GENERIC_UART_INIT config invisible. - Add SPDX tag and update the comment in uart-init.c. - Update the commit message. --- Changes in V3: - Drop blank line in xen/drivers/char/Kconfig. - Rebase on top of the latest staging. --- Changes in v2: - Rename arm-uart.c to uart-init.c instead of moving only dt_uart_init() to separate file. - Introduce new CONFIG_UART_INIT. - Rename arm_uart_init() to uart_init(). - Add 'select UART_INIT' for CONFIG_ARM to be sure that randconfig won't disable UART_INIT. - Update the commit message. --- MAINTAINERS | 1 - xen/arch/arm/Kconfig | 1 + xen/arch/arm/setup.c | 2 +- xen/drivers/char/Kconfig | 3 + xen/drivers/char/Makefile | 2 +- xen/drivers/char/arm-uart.c | 145 ----------------------------------- xen/drivers/char/uart-init.c | 138 +++++++++++++++++++++++++++++++++ xen/include/xen/serial.h | 2 +- 8 files changed, 145 insertions(+), 149 deletions(-) delete mode 100644 xen/drivers/char/arm-uart.c create mode 100644 xen/drivers/char/uart-init.c diff --git a/MAINTAINERS b/MAINTAINERS index 17fc5f9eec..026aa25a53 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -245,7 +245,6 @@ S: Supported L: xen-devel@xxxxxxxxxxxxxxxxxxxx F: docs/misc/arm/ F: xen/arch/arm/ -F: xen/drivers/char/arm-uart.c F: xen/drivers/char/cadence-uart.c F: xen/drivers/char/exynos4210-uart.c F: xen/drivers/char/imx-lpuart.c diff --git a/xen/arch/arm/Kconfig b/xen/arch/arm/Kconfig index 15b2e4a227..23bbc91aad 100644 --- a/xen/arch/arm/Kconfig +++ b/xen/arch/arm/Kconfig @@ -12,6 +12,7 @@ config ARM_64 config ARM def_bool y select FUNCTION_ALIGNMENT_4B + select GENERIC_UART_INIT select HAS_ALTERNATIVE if HAS_VMAP select HAS_DEVICE_TREE select HAS_PASSTHROUGH diff --git a/xen/arch/arm/setup.c b/xen/arch/arm/setup.c index 71ebaa77ca..2e27af4560 100644 --- a/xen/arch/arm/setup.c +++ b/xen/arch/arm/setup.c @@ -361,7 +361,7 @@ void asmlinkage __init start_xen(unsigned long fdt_paddr) gic_preinit(); - arm_uart_init(); + uart_init(); console_init_preirq(); console_init_ring(); diff --git a/xen/drivers/char/Kconfig b/xen/drivers/char/Kconfig index e175d07c02..e6e12bb413 100644 --- a/xen/drivers/char/Kconfig +++ b/xen/drivers/char/Kconfig @@ -1,3 +1,6 @@ +config GENERIC_UART_INIT + bool + config HAS_NS16550 bool "NS16550 UART driver" if ARM default n if RISCV diff --git a/xen/drivers/char/Makefile b/xen/drivers/char/Makefile index d3b987da1d..8cbbffdca8 100644 --- a/xen/drivers/char/Makefile +++ b/xen/drivers/char/Makefile @@ -11,7 +11,7 @@ obj-$(CONFIG_HAS_EHCI) += ehci-dbgp.o obj-$(CONFIG_XHCI) += xhci-dbc.o obj-$(CONFIG_HAS_IMX_LPUART) += imx-lpuart.o obj-$(CONFIG_HAS_LINFLEX) += linflex-uart.o -obj-$(CONFIG_ARM) += arm-uart.o +obj-$(CONFIG_GENERIC_UART_INIT) += uart-init.o obj-y += serial.o obj-$(CONFIG_XEN_GUEST) += xen_pv_console.o obj-$(CONFIG_PV_SHIM) += consoled.o diff --git a/xen/drivers/char/arm-uart.c b/xen/drivers/char/arm-uart.c deleted file mode 100644 index 91f13a4136..0000000000 --- a/xen/drivers/char/arm-uart.c +++ /dev/null @@ -1,145 +0,0 @@ -/* - * xen/drivers/char/arm-uart.c - * - * Generic uart retrieved via the device tree or ACPI - * - * Julien Grall <julien.grall@xxxxxxxxxx> - * Copyright (c) 2013 Linaro Limited. - * - * This program is free software; you can redistribute it and/or modify - * it under the terms of the GNU General Public License as published by - * the Free Software Foundation; either version 2 of the License, or - * (at your option) any later version. - * - * This program is distributed in the hope that it will be useful, - * but WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the - * GNU General Public License for more details. - */ - -#include <asm/device.h> - -#include <xen/console.h> -#include <xen/device_tree.h> -#include <xen/param.h> -#include <xen/serial.h> -#include <xen/errno.h> -#include <xen/acpi.h> - -/* - * Configure UART port with a string: - * path:options - * - * @path: full path used in the device tree for the UART. If the path - * doesn't start with '/', we assuming that it's an alias. - * @options: UART speficic options (see in each UART driver) - */ -static char __initdata opt_dtuart[256] = ""; -string_param("dtuart", opt_dtuart); - -static void __init dt_uart_init(void) -{ - struct dt_device_node *dev; - int ret; - const char *devpath = opt_dtuart; - const char *options; - char *split; - - if ( !console_has("dtuart") ) - return; /* Not for us */ - - if ( !strcmp(opt_dtuart, "") ) - { - const struct dt_device_node *chosen = dt_find_node_by_path("/chosen"); - - if ( chosen ) - { - const char *stdout; - - ret = dt_property_read_string(chosen, "stdout-path", &stdout); - if ( ret >= 0 ) - { - printk("Taking dtuart configuration from /chosen/stdout-path\n"); - if ( strlcpy(opt_dtuart, stdout, sizeof(opt_dtuart)) - >= sizeof(opt_dtuart) ) - printk("WARNING: /chosen/stdout-path too long, truncated\n"); - } - else if ( ret != -EINVAL /* Not present */ ) - printk("Failed to read /chosen/stdout-path (%d)\n", ret); - } - } - - if ( !strcmp(opt_dtuart, "") ) - { - printk("No dtuart path configured\n"); - return; - } - - split = strchr(opt_dtuart, ':'); - if ( split ) - { - split[0] = '\0'; - options = split + 1; - } - else - options = ""; - - printk("Looking for dtuart at \"%s\", options \"%s\"\n", devpath, options); - if ( *devpath == '/' ) - dev = dt_find_node_by_path(devpath); - else - dev = dt_find_node_by_alias(devpath); - - if ( !dev ) - { - printk("Unable to find device \"%s\"\n", devpath); - return; - } - - ret = device_init(dev, DEVICE_SERIAL, options); - - if ( ret ) - printk("Unable to initialize dtuart: %d\n", ret); -} - -#ifdef CONFIG_ACPI -static void __init acpi_uart_init(void) -{ - struct acpi_table_spcr *spcr = NULL; - int ret; - - acpi_get_table(ACPI_SIG_SPCR, 0, (struct acpi_table_header **)&spcr); - - if ( spcr == NULL ) - { - printk("Unable to get spcr table\n"); - } - else - { - ret = acpi_device_init(DEVICE_SERIAL, NULL, spcr->interface_type); - - if ( ret ) - printk("Unable to initialize acpi uart: %d\n", ret); - } -} -#else -static void __init acpi_uart_init(void) { } -#endif - -void __init arm_uart_init(void) -{ - if ( acpi_disabled ) - dt_uart_init(); - else - acpi_uart_init(); -} - -/* - * Local variables: - * mode: C - * c-file-style: "BSD" - * c-basic-offset: 4 - * tab-width: 4 - * indent-tabs-mode: nil - * End: - */ diff --git a/xen/drivers/char/uart-init.c b/xen/drivers/char/uart-init.c new file mode 100644 index 0000000000..a218139938 --- /dev/null +++ b/xen/drivers/char/uart-init.c @@ -0,0 +1,138 @@ +/* SPDX-License-Identifier: GPL-2.0-or-later */ + +/* + * Derived from: + * xen/drivers/char/arm-uart.c + * + * Generic uart retrieved via the device tree or ACPI + * + * Julien Grall <julien.grall@xxxxxxxxxx> + * Copyright (c) 2013 Linaro Limited. + */ + +#include <asm/device.h> + +#include <xen/console.h> +#include <xen/device_tree.h> +#include <xen/param.h> +#include <xen/serial.h> +#include <xen/errno.h> +#include <xen/acpi.h> + +/* + * Configure UART port with a string: + * path:options + * + * @path: full path used in the device tree for the UART. If the path + * doesn't start with '/', we assuming that it's an alias. + * @options: UART speficic options (see in each UART driver) + */ +static char __initdata opt_dtuart[256] = ""; +string_param("dtuart", opt_dtuart); + +static void __init dt_uart_init(void) +{ + struct dt_device_node *dev; + int ret; + const char *devpath = opt_dtuart; + const char *options; + char *split; + + if ( !console_has("dtuart") ) + return; /* Not for us */ + + if ( !strcmp(opt_dtuart, "") ) + { + const struct dt_device_node *chosen = dt_find_node_by_path("/chosen"); + + if ( chosen ) + { + const char *stdout; + + ret = dt_property_read_string(chosen, "stdout-path", &stdout); + if ( ret >= 0 ) + { + printk("Taking dtuart configuration from /chosen/stdout-path\n"); + if ( strlcpy(opt_dtuart, stdout, sizeof(opt_dtuart)) + >= sizeof(opt_dtuart) ) + printk("WARNING: /chosen/stdout-path too long, truncated\n"); + } + else if ( ret != -EINVAL /* Not present */ ) + printk("Failed to read /chosen/stdout-path (%d)\n", ret); + } + } + + if ( !strcmp(opt_dtuart, "") ) + { + printk("No dtuart path configured\n"); + return; + } + + split = strchr(opt_dtuart, ':'); + if ( split ) + { + split[0] = '\0'; + options = split + 1; + } + else + options = ""; + + printk("Looking for dtuart at \"%s\", options \"%s\"\n", devpath, options); + if ( *devpath == '/' ) + dev = dt_find_node_by_path(devpath); + else + dev = dt_find_node_by_alias(devpath); + + if ( !dev ) + { + printk("Unable to find device \"%s\"\n", devpath); + return; + } + + ret = device_init(dev, DEVICE_SERIAL, options); + + if ( ret ) + printk("Unable to initialize dtuart: %d\n", ret); +} + +#ifdef CONFIG_ACPI +static void __init acpi_uart_init(void) +{ + struct acpi_table_spcr *spcr = NULL; + int ret; + + acpi_get_table(ACPI_SIG_SPCR, 0, (struct acpi_table_header **)&spcr); + + if ( spcr == NULL ) + { + printk("Unable to get spcr table\n"); + } + else + { + ret = acpi_device_init(DEVICE_SERIAL, NULL, spcr->interface_type); + + if ( ret ) + printk("Unable to initialize acpi uart: %d\n", ret); + } +} +#else +static void __init acpi_uart_init(void) { } +#endif + +void __init uart_init(void) +{ + if ( acpi_disabled ) + dt_uart_init(); + else + acpi_uart_init(); +} + +/* + * Local variables: + * mode: C + * c-file-style: "BSD" + * c-basic-offset: 4 + * tab-width: 4 + * indent-tabs-mode: nil + * End: + */ diff --git a/xen/include/xen/serial.h b/xen/include/xen/serial.h index 3d21207a3d..63a82b032d 100644 --- a/xen/include/xen/serial.h +++ b/xen/include/xen/serial.h @@ -166,7 +166,7 @@ void xhci_dbc_uart_init(void); static void inline xhci_dbc_uart_init(void) {} #endif -void arm_uart_init(void); +void uart_init(void); struct physdev_dbgp_op; int dbgp_op(const struct physdev_dbgp_op *op); -- 2.47.0

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