Add driver support for the LPC UART routing control. Users can perform runtime configuration of the RX muxes among the UART controllers and the UART IO pins. A sysfs interface is also exported for the convenience of routing paths check and configuration. Signed-off-by: Chia-Wei Wang <chiawei_wang@xxxxxxxxxxxxxx> --- .../testing/sysfs-driver-aspeed-uart-routing | 15 + drivers/soc/aspeed/Kconfig | 10 + drivers/soc/aspeed/Makefile | 9 +- drivers/soc/aspeed/aspeed-uart-routing.c | 601 ++++++++++++++++++ 4 files changed, 631 insertions(+), 4 deletions(-) create mode 100644 Documentation/ABI/testing/sysfs-driver-aspeed-uart-routing create mode 100644 drivers/soc/aspeed/aspeed-uart-routing.c diff --git a/Documentation/ABI/testing/sysfs-driver-aspeed-uart-routing b/Documentation/ABI/testing/sysfs-driver-aspeed-uart-routing new file mode 100644 index 000000000000..65f899f1f055 --- /dev/null +++ b/Documentation/ABI/testing/sysfs-driver-aspeed-uart-routing @@ -0,0 +1,15 @@ +What: /sys/bus/platform/drivers/aspeed-uart-routing/*/uart* +Date: September 2021 +Contact: Chia-Wei Wang <chiawei_wang@xxxxxxxxxxxxxx> +Description: Selects the RX source of the UARTx device. The current + selection will be marked with the '[]' brackets. +Users: OpenBMC. Proposed changes should be mailed to + openbmc@xxxxxxxxxxxxxxxx + +What: /sys/bus/platform/drivers/aspeed-uart-routing/*/io* +Date: September 2021 +Contact: Chia-Wei Wang <chiawei_wang@xxxxxxxxxxxxxx> +Description: Selects the RX source of IOx pins. The current selection + will be marked with the '[]' brackets. +Users: OpenBMC. Proposed changes should be mailed to + openbmc@xxxxxxxxxxxxxxxx diff --git a/drivers/soc/aspeed/Kconfig b/drivers/soc/aspeed/Kconfig index 243ca196e6ad..f579ee0b5afa 100644 --- a/drivers/soc/aspeed/Kconfig +++ b/drivers/soc/aspeed/Kconfig @@ -24,6 +24,16 @@ config ASPEED_LPC_SNOOP allows the BMC to listen on and save the data written by the host to an arbitrary LPC I/O port. +config ASPEED_UART_ROUTING + tristate "ASPEED uart routing control" + select REGMAP + select MFD_SYSCON + default ARCH_ASPEED + help + Provides a driver to control the UART routing paths, allowing + users to perform runtime configuration of the RX muxes among + the UART controllers and I/O pins. + config ASPEED_P2A_CTRL tristate "ASPEED P2A (VGA MMIO to BMC) bridge control" select REGMAP diff --git a/drivers/soc/aspeed/Makefile b/drivers/soc/aspeed/Makefile index fcab7192e1a4..b35d74592964 100644 --- a/drivers/soc/aspeed/Makefile +++ b/drivers/soc/aspeed/Makefile @@ -1,5 +1,6 @@ # SPDX-License-Identifier: GPL-2.0-only -obj-$(CONFIG_ASPEED_LPC_CTRL) += aspeed-lpc-ctrl.o -obj-$(CONFIG_ASPEED_LPC_SNOOP) += aspeed-lpc-snoop.o -obj-$(CONFIG_ASPEED_P2A_CTRL) += aspeed-p2a-ctrl.o -obj-$(CONFIG_ASPEED_SOCINFO) += aspeed-socinfo.o +obj-$(CONFIG_ASPEED_LPC_CTRL) += aspeed-lpc-ctrl.o +obj-$(CONFIG_ASPEED_LPC_SNOOP) += aspeed-lpc-snoop.o +obj-$(CONFIG_ASPEED_UART_ROUTING) += aspeed-uart-routing.o +obj-$(CONFIG_ASPEED_P2A_CTRL) += aspeed-p2a-ctrl.o +obj-$(CONFIG_ASPEED_SOCINFO) += aspeed-socinfo.o diff --git a/drivers/soc/aspeed/aspeed-uart-routing.c b/drivers/soc/aspeed/aspeed-uart-routing.c new file mode 100644 index 000000000000..eba6dfebb54f --- /dev/null +++ b/drivers/soc/aspeed/aspeed-uart-routing.c @@ -0,0 +1,601 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * Copyright (c) 2018 Google LLC + * Copyright (c) 2021 Aspeed Technology Inc. + */ +#include <linux/device.h> +#include <linux/module.h> +#include <linux/of_device.h> +#include <linux/of_platform.h> +#include <linux/mfd/syscon.h> +#include <linux/regmap.h> +#include <linux/platform_device.h> + +/* register offsets */ +#define HICR9 0x98 +#define HICRA 0x9c + +/* attributes options */ +#define UART_ROUTING_IO1 "io1" +#define UART_ROUTING_IO2 "io2" +#define UART_ROUTING_IO3 "io3" +#define UART_ROUTING_IO4 "io4" +#define UART_ROUTING_IO5 "io5" +#define UART_ROUTING_IO6 "io6" +#define UART_ROUTING_IO10 "io10" +#define UART_ROUTING_UART1 "uart1" +#define UART_ROUTING_UART2 "uart2" +#define UART_ROUTING_UART3 "uart3" +#define UART_ROUTING_UART4 "uart4" +#define UART_ROUTING_UART5 "uart5" +#define UART_ROUTING_UART6 "uart6" +#define UART_ROUTING_UART10 "uart10" +#define UART_ROUTING_RES "reserved" + +struct aspeed_uart_routing { + struct regmap *map; + struct attribute_group const *attr_grp; +}; + +struct aspeed_uart_routing_selector { + struct device_attribute dev_attr; + uint8_t reg; + uint8_t mask; + uint8_t shift; + const char *const options[]; +}; + +#define to_routing_selector(_dev_attr) \ + container_of(_dev_attr, struct aspeed_uart_routing_selector, dev_attr) + +static ssize_t aspeed_uart_routing_show(struct device *dev, + struct device_attribute *attr, + char *buf); + +static ssize_t aspeed_uart_routing_store(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t count); + +#define ROUTING_ATTR(_name) { \ + .attr = {.name = _name, \ + .mode = VERIFY_OCTAL_PERMISSIONS(0644) }, \ + .show = aspeed_uart_routing_show, \ + .store = aspeed_uart_routing_store, \ +} + +/* routing selector for AST25xx */ +static struct aspeed_uart_routing_selector ast2500_io6_sel = { + .dev_attr = ROUTING_ATTR(UART_ROUTING_IO6), + .reg = HICR9, + .shift = 8, + .mask = 0xf, + .options = { + UART_ROUTING_UART1, + UART_ROUTING_UART2, + UART_ROUTING_UART3, + UART_ROUTING_UART4, + UART_ROUTING_UART5, + UART_ROUTING_IO1, + UART_ROUTING_IO2, + UART_ROUTING_IO3, + UART_ROUTING_IO4, + UART_ROUTING_IO5, + NULL, + }, +}; + +static struct aspeed_uart_routing_selector ast2500_uart5_sel = { + .dev_attr = ROUTING_ATTR(UART_ROUTING_UART5), + .reg = HICRA, + .shift = 28, + .mask = 0xf, + .options = { + UART_ROUTING_IO5, + UART_ROUTING_IO1, + UART_ROUTING_IO2, + UART_ROUTING_IO3, + UART_ROUTING_IO4, + UART_ROUTING_UART1, + UART_ROUTING_UART2, + UART_ROUTING_UART3, + UART_ROUTING_UART4, + UART_ROUTING_IO6, + NULL, + }, +}; + +static struct aspeed_uart_routing_selector ast2500_uart4_sel = { + .dev_attr = ROUTING_ATTR(UART_ROUTING_UART4), + .reg = HICRA, + .shift = 25, + .mask = 0x7, + .options = { + UART_ROUTING_IO4, + UART_ROUTING_IO1, + UART_ROUTING_IO2, + UART_ROUTING_IO3, + UART_ROUTING_UART1, + UART_ROUTING_UART2, + UART_ROUTING_UART3, + UART_ROUTING_IO6, + NULL, + }, +}; + +static struct aspeed_uart_routing_selector ast2500_uart3_sel = { + .dev_attr = ROUTING_ATTR(UART_ROUTING_UART3), + .reg = HICRA, + .shift = 22, + .mask = 0x7, + .options = { + UART_ROUTING_IO3, + UART_ROUTING_IO4, + UART_ROUTING_IO1, + UART_ROUTING_IO2, + UART_ROUTING_UART4, + UART_ROUTING_UART1, + UART_ROUTING_UART2, + UART_ROUTING_IO6, + NULL, + }, +}; + +static struct aspeed_uart_routing_selector ast2500_uart2_sel = { + .dev_attr = ROUTING_ATTR(UART_ROUTING_UART2), + .reg = HICRA, + .shift = 19, + .mask = 0x7, + .options = { + UART_ROUTING_IO2, + UART_ROUTING_IO3, + UART_ROUTING_IO4, + UART_ROUTING_IO1, + UART_ROUTING_UART3, + UART_ROUTING_UART4, + UART_ROUTING_UART1, + UART_ROUTING_IO6, + NULL, + }, +}; + +static struct aspeed_uart_routing_selector ast2500_uart1_sel = { + .dev_attr = ROUTING_ATTR(UART_ROUTING_UART1), + .reg = HICRA, + .shift = 16, + .mask = 0x7, + .options = { + UART_ROUTING_IO1, + UART_ROUTING_IO2, + UART_ROUTING_IO3, + UART_ROUTING_IO4, + UART_ROUTING_UART2, + UART_ROUTING_UART3, + UART_ROUTING_UART4, + UART_ROUTING_IO6, + NULL, + }, +}; + +static struct aspeed_uart_routing_selector ast2500_io5_sel = { + .dev_attr = ROUTING_ATTR(UART_ROUTING_IO5), + .reg = HICRA, + .shift = 12, + .mask = 0x7, + .options = { + UART_ROUTING_UART5, + UART_ROUTING_UART1, + UART_ROUTING_UART2, + UART_ROUTING_UART3, + UART_ROUTING_UART4, + UART_ROUTING_IO1, + UART_ROUTING_IO3, + UART_ROUTING_IO6, + NULL, + }, +}; + +static struct aspeed_uart_routing_selector ast2500_io4_sel = { + .dev_attr = ROUTING_ATTR(UART_ROUTING_IO4), + .reg = HICRA, + .shift = 9, + .mask = 0x7, + .options = { + UART_ROUTING_UART4, + UART_ROUTING_UART5, + UART_ROUTING_UART1, + UART_ROUTING_UART2, + UART_ROUTING_UART3, + UART_ROUTING_IO1, + UART_ROUTING_IO2, + UART_ROUTING_IO6, + NULL, + }, +}; + +static struct aspeed_uart_routing_selector ast2500_io3_sel = { + .dev_attr = ROUTING_ATTR(UART_ROUTING_IO3), + .reg = HICRA, + .shift = 6, + .mask = 0x7, + .options = { + UART_ROUTING_UART3, + UART_ROUTING_UART4, + UART_ROUTING_UART5, + UART_ROUTING_UART1, + UART_ROUTING_UART2, + UART_ROUTING_IO1, + UART_ROUTING_IO2, + UART_ROUTING_IO6, + NULL, + }, +}; + +static struct aspeed_uart_routing_selector ast2500_io2_sel = { + .dev_attr = ROUTING_ATTR(UART_ROUTING_IO2), + .reg = HICRA, + .shift = 3, + .mask = 0x7, + .options = { + UART_ROUTING_UART2, + UART_ROUTING_UART3, + UART_ROUTING_UART4, + UART_ROUTING_UART5, + UART_ROUTING_UART1, + UART_ROUTING_IO3, + UART_ROUTING_IO4, + UART_ROUTING_IO6, + NULL, + }, +}; + +static struct aspeed_uart_routing_selector ast2500_io1_sel = { + .dev_attr = ROUTING_ATTR(UART_ROUTING_IO1), + .reg = HICRA, + .shift = 0, + .mask = 0x7, + .options = { + UART_ROUTING_UART1, + UART_ROUTING_UART2, + UART_ROUTING_UART3, + UART_ROUTING_UART4, + UART_ROUTING_UART5, + UART_ROUTING_IO3, + UART_ROUTING_IO4, + UART_ROUTING_IO6, + NULL, + }, +}; + +static struct attribute *ast2500_uart_routing_attrs[] = { + &ast2500_io6_sel.dev_attr.attr, + &ast2500_uart5_sel.dev_attr.attr, + &ast2500_uart4_sel.dev_attr.attr, + &ast2500_uart3_sel.dev_attr.attr, + &ast2500_uart2_sel.dev_attr.attr, + &ast2500_uart1_sel.dev_attr.attr, + &ast2500_io5_sel.dev_attr.attr, + &ast2500_io4_sel.dev_attr.attr, + &ast2500_io3_sel.dev_attr.attr, + &ast2500_io2_sel.dev_attr.attr, + &ast2500_io1_sel.dev_attr.attr, + NULL, +}; + +static const struct attribute_group ast2500_uart_routing_attr_group = { + .attrs = ast2500_uart_routing_attrs, +}; + +/* routing selector for AST26xx */ +static struct aspeed_uart_routing_selector ast2600_uart10_sel = { + .dev_attr = ROUTING_ATTR(UART_ROUTING_UART10), + .reg = HICR9, + .shift = 12, + .mask = 0xf, + .options = { + UART_ROUTING_IO10, + UART_ROUTING_IO1, + UART_ROUTING_IO2, + UART_ROUTING_IO3, + UART_ROUTING_IO4, + UART_ROUTING_RES, + UART_ROUTING_UART1, + UART_ROUTING_UART2, + UART_ROUTING_UART3, + UART_ROUTING_UART4, + NULL, + }, +}; + +static struct aspeed_uart_routing_selector ast2600_io10_sel = { + .dev_attr = ROUTING_ATTR(UART_ROUTING_IO10), + .reg = HICR9, + .shift = 8, + .mask = 0xf, + .options = { + UART_ROUTING_UART1, + UART_ROUTING_UART2, + UART_ROUTING_UART3, + UART_ROUTING_UART4, + UART_ROUTING_RES, + UART_ROUTING_IO1, + UART_ROUTING_IO2, + UART_ROUTING_IO3, + UART_ROUTING_IO4, + UART_ROUTING_RES, + UART_ROUTING_UART10, + NULL, + }, +}; + +static struct aspeed_uart_routing_selector ast2600_uart4_sel = { + .dev_attr = ROUTING_ATTR(UART_ROUTING_UART4), + .reg = HICRA, + .shift = 25, + .mask = 0x7, + .options = { + UART_ROUTING_IO4, + UART_ROUTING_IO1, + UART_ROUTING_IO2, + UART_ROUTING_IO3, + UART_ROUTING_UART1, + UART_ROUTING_UART2, + UART_ROUTING_UART3, + UART_ROUTING_IO10, + NULL, + }, +}; + +static struct aspeed_uart_routing_selector ast2600_uart3_sel = { + .dev_attr = ROUTING_ATTR(UART_ROUTING_UART3), + .reg = HICRA, + .shift = 22, + .mask = 0x7, + .options = { + UART_ROUTING_IO3, + UART_ROUTING_IO4, + UART_ROUTING_IO1, + UART_ROUTING_IO2, + UART_ROUTING_UART4, + UART_ROUTING_UART1, + UART_ROUTING_UART2, + UART_ROUTING_IO10, + NULL, + }, +}; + +static struct aspeed_uart_routing_selector ast2600_uart2_sel = { + .dev_attr = ROUTING_ATTR(UART_ROUTING_UART2), + .reg = HICRA, + .shift = 19, + .mask = 0x7, + .options = { + UART_ROUTING_IO2, + UART_ROUTING_IO3, + UART_ROUTING_IO4, + UART_ROUTING_IO1, + UART_ROUTING_UART3, + UART_ROUTING_UART4, + UART_ROUTING_UART1, + UART_ROUTING_IO10, + NULL, + }, +}; + +static struct aspeed_uart_routing_selector ast2600_uart1_sel = { + .dev_attr = ROUTING_ATTR(UART_ROUTING_UART1), + .reg = HICRA, + .shift = 16, + .mask = 0x7, + .options = { + UART_ROUTING_IO1, + UART_ROUTING_IO2, + UART_ROUTING_IO3, + UART_ROUTING_IO4, + UART_ROUTING_UART2, + UART_ROUTING_UART3, + UART_ROUTING_UART4, + UART_ROUTING_IO10, + NULL, + }, +}; + +static struct aspeed_uart_routing_selector ast2600_io4_sel = { + .dev_attr = ROUTING_ATTR(UART_ROUTING_IO4), + .reg = HICRA, + .shift = 9, + .mask = 0x7, + .options = { + UART_ROUTING_UART4, + UART_ROUTING_UART10, + UART_ROUTING_UART1, + UART_ROUTING_UART2, + UART_ROUTING_UART3, + UART_ROUTING_IO1, + UART_ROUTING_IO2, + UART_ROUTING_IO10, + NULL, + }, +}; + +static struct aspeed_uart_routing_selector ast2600_io3_sel = { + .dev_attr = ROUTING_ATTR(UART_ROUTING_IO3), + .reg = HICRA, + .shift = 6, + .mask = 0x7, + .options = { + UART_ROUTING_UART3, + UART_ROUTING_UART4, + UART_ROUTING_UART10, + UART_ROUTING_UART1, + UART_ROUTING_UART2, + UART_ROUTING_IO1, + UART_ROUTING_IO2, + UART_ROUTING_IO10, + NULL, + }, +}; + +static struct aspeed_uart_routing_selector ast2600_io2_sel = { + .dev_attr = ROUTING_ATTR(UART_ROUTING_IO2), + .reg = HICRA, + .shift = 3, + .mask = 0x7, + .options = { + UART_ROUTING_UART2, + UART_ROUTING_UART3, + UART_ROUTING_UART4, + UART_ROUTING_UART10, + UART_ROUTING_UART1, + UART_ROUTING_IO3, + UART_ROUTING_IO4, + UART_ROUTING_IO10, + NULL, + }, +}; + +static struct aspeed_uart_routing_selector ast2600_io1_sel = { + .dev_attr = ROUTING_ATTR(UART_ROUTING_IO1), + .reg = HICRA, + .shift = 0, + .mask = 0x7, + .options = { + UART_ROUTING_UART1, + UART_ROUTING_UART2, + UART_ROUTING_UART3, + UART_ROUTING_UART4, + UART_ROUTING_UART10, + UART_ROUTING_IO3, + UART_ROUTING_IO4, + UART_ROUTING_IO10, + NULL, + }, +}; + +static struct attribute *ast2600_uart_routing_attrs[] = { + &ast2600_uart10_sel.dev_attr.attr, + &ast2600_io10_sel.dev_attr.attr, + &ast2600_uart4_sel.dev_attr.attr, + &ast2600_uart3_sel.dev_attr.attr, + &ast2600_uart2_sel.dev_attr.attr, + &ast2600_uart1_sel.dev_attr.attr, + &ast2600_io4_sel.dev_attr.attr, + &ast2600_io3_sel.dev_attr.attr, + &ast2600_io2_sel.dev_attr.attr, + &ast2600_io1_sel.dev_attr.attr, + NULL, +}; + +static const struct attribute_group ast2600_uart_routing_attr_group = { + .attrs = ast2600_uart_routing_attrs, +}; + +static ssize_t aspeed_uart_routing_show(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + struct aspeed_uart_routing *uart_routing = dev_get_drvdata(dev); + struct aspeed_uart_routing_selector *sel = to_routing_selector(attr); + int val, pos, len; + + regmap_read(uart_routing->map, sel->reg, &val); + val = (val >> sel->shift) & sel->mask; + + len = 0; + for (pos = 0; sel->options[pos] != NULL; ++pos) { + if (pos == val) + len += sysfs_emit_at(buf, len, "[%s] ", sel->options[pos]); + else + len += sysfs_emit_at(buf, len, "%s ", sel->options[pos]); + } + + if (val >= pos) + len += sysfs_emit_at(buf, len, "[unknown(%d)]", val); + + len += sysfs_emit_at(buf, len, "\n"); + + return len; +} + +static ssize_t aspeed_uart_routing_store(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t count) +{ + struct aspeed_uart_routing *uart_routing = dev_get_drvdata(dev); + struct aspeed_uart_routing_selector *sel = to_routing_selector(attr); + int val; + + val = match_string(sel->options, -1, buf); + if (val < 0) { + dev_err(dev, "invalid value \"%s\"\n", buf); + return -EINVAL; + } + + regmap_update_bits(uart_routing->map, sel->reg, + (sel->mask << sel->shift), + (val & sel->mask) << sel->shift); + + return count; +} + +static int aspeed_uart_routing_probe(struct platform_device *pdev) +{ + int rc; + struct device *dev = &pdev->dev; + struct aspeed_uart_routing *uart_routing; + + uart_routing = devm_kzalloc(&pdev->dev, sizeof(*uart_routing), GFP_KERNEL); + if (!uart_routing) + return -ENOMEM; + + uart_routing->map = syscon_node_to_regmap(dev->parent->of_node); + if (IS_ERR(uart_routing->map)) { + dev_err(dev, "cannot get regmap\n"); + return PTR_ERR(uart_routing->map); + } + + uart_routing->attr_grp = of_device_get_match_data(dev); + + rc = sysfs_create_group(&dev->kobj, uart_routing->attr_grp); + if (rc < 0) + return rc; + + dev_set_drvdata(dev, uart_routing); + + dev_info(dev, "module loaded\n"); + + return 0; +} + +static int aspeed_uart_routing_remove(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct aspeed_uart_routing *uart_routing = platform_get_drvdata(pdev); + + sysfs_remove_group(&dev->kobj, uart_routing->attr_grp); + + return 0; +} + +static const struct of_device_id aspeed_uart_routing_table[] = { + { .compatible = "aspeed,ast2500-uart-routing", + .data = &ast2500_uart_routing_attr_group }, + { .compatible = "aspeed,ast2600-uart-routing", + .data = &ast2600_uart_routing_attr_group }, + { }, +}; + +static struct platform_driver aspeed_uart_routing_driver = { + .driver = { + .name = "aspeed-uart-routing", + .of_match_table = aspeed_uart_routing_table, + }, + .probe = aspeed_uart_routing_probe, + .remove = aspeed_uart_routing_remove, +}; + +module_platform_driver(aspeed_uart_routing_driver); + +MODULE_AUTHOR("Oskar Senft <osk@xxxxxxxxxx>"); +MODULE_AUTHOR("Chia-Wei Wang <chiawei_wang@xxxxxxxxxxxxxx>"); +MODULE_LICENSE("GPL v2"); +MODULE_DESCRIPTION("Driver to configure Aspeed UART routing"); -- 2.17.1