From: Krzysztof Kozlowski Date: Wed, 17 Sep 2025 01:04:38 +0000 (+0900) Subject: serial: qcom-geni: Fix blocked task X-Git-Tag: v6.18-rc1~46^2 X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=a699213d4e6ef4286348c6439837990f121e0c03;p=thirdparty%2Fkernel%2Fstable.git serial: qcom-geni: Fix blocked task Revert commit 1afa70632c39 ("serial: qcom-geni: Enable PM runtime for serial driver") and its dependent commit 86fa39dd6fb7 ("serial: qcom-geni: Enable Serial on SA8255p Qualcomm platforms") because the first one causes regression - hang task on Qualcomm RB1 board (QRB2210) and unable to use serial at all during normal boot: INFO: task kworker/u16:0:12 blocked for more than 42 seconds. Not tainted 6.17.0-rc1-00004-g53e760d89498 #9 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u16:0 state:D stack:0 pid:12 tgid:12 ppid:2 task_flags:0x4208060 flags:0x00000010 Workqueue: async async_run_entry_fn Call trace: __switch_to+0xe8/0x1a0 (T) __schedule+0x290/0x7c0 schedule+0x34/0x118 rpm_resume+0x14c/0x66c rpm_resume+0x2a4/0x66c rpm_resume+0x2a4/0x66c rpm_resume+0x2a4/0x66c __pm_runtime_resume+0x50/0x9c __driver_probe_device+0x58/0x120 driver_probe_device+0x3c/0x154 __driver_attach_async_helper+0x4c/0xc0 async_run_entry_fn+0x34/0xe0 process_one_work+0x148/0x290 worker_thread+0x2c4/0x3e0 kthread+0x118/0x1c0 ret_from_fork+0x10/0x20 The issue was reported on 12th of August and was ignored by author of commits introducing issue for two weeks. Only after complaining author produced a fix which did not work, so if original commits cannot be reliably fixed for 5 weeks, they obviously are buggy and need to be dropped. Fixes: 1afa70632c39 ("serial: qcom-geni: Enable PM runtime for serial driver") Reported-by: Alexey Klimov Closes: https://lore.kernel.org/all/DC0D53ZTNOBU.E8LSD5E5Z8TX@linaro.org/ Signed-off-by: Krzysztof Kozlowski Tested-by: Alexey Klimov Reviewed-by: Alexey Klimov Reviewed-by: Bryan O'Donoghue Link: https://lore.kernel.org/r/20250917010437.129912-2-krzysztof.kozlowski@linaro.org Signed-off-by: Greg Kroah-Hartman --- diff --git a/drivers/tty/serial/qcom_geni_serial.c b/drivers/tty/serial/qcom_geni_serial.c index 32ec632fd0807..81f385d900d06 100644 --- a/drivers/tty/serial/qcom_geni_serial.c +++ b/drivers/tty/serial/qcom_geni_serial.c @@ -11,7 +11,6 @@ #include #include #include -#include #include #include #include @@ -100,16 +99,10 @@ #define DMA_RX_BUF_SIZE 2048 static DEFINE_IDA(port_ida); -#define DOMAIN_IDX_POWER 0 -#define DOMAIN_IDX_PERF 1 struct qcom_geni_device_data { bool console; enum geni_se_xfer_mode mode; - struct dev_pm_domain_attach_data pd_data; - int (*resources_init)(struct uart_port *uport); - int (*set_rate)(struct uart_port *uport, unsigned int baud); - int (*power_state)(struct uart_port *uport, bool state); }; struct qcom_geni_private_data { @@ -147,7 +140,6 @@ struct qcom_geni_serial_port { struct qcom_geni_private_data private_data; const struct qcom_geni_device_data *dev_data; - struct dev_pm_domain_list *pd_list; }; static const struct uart_ops qcom_geni_console_pops; @@ -1370,42 +1362,6 @@ static int geni_serial_set_rate(struct uart_port *uport, unsigned int baud) return 0; } -static int geni_serial_set_level(struct uart_port *uport, unsigned int baud) -{ - struct qcom_geni_serial_port *port = to_dev_port(uport); - struct device *perf_dev = port->pd_list->pd_devs[DOMAIN_IDX_PERF]; - - /* - * The performance protocol sets UART communication - * speeds by selecting different performance levels - * through the OPP framework. - * - * Supported perf levels for baudrates in firmware are below - * +---------------------+--------------------+ - * | Perf level value | Baudrate values | - * +---------------------+--------------------+ - * | 300 | 300 | - * | 1200 | 1200 | - * | 2400 | 2400 | - * | 4800 | 4800 | - * | 9600 | 9600 | - * | 19200 | 19200 | - * | 38400 | 38400 | - * | 57600 | 57600 | - * | 115200 | 115200 | - * | 230400 | 230400 | - * | 460800 | 460800 | - * | 921600 | 921600 | - * | 2000000 | 2000000 | - * | 3000000 | 3000000 | - * | 3200000 | 3200000 | - * | 4000000 | 4000000 | - * +---------------------+--------------------+ - */ - - return dev_pm_opp_set_level(perf_dev, baud); -} - static void qcom_geni_serial_set_termios(struct uart_port *uport, struct ktermios *termios, const struct ktermios *old) @@ -1424,7 +1380,7 @@ static void qcom_geni_serial_set_termios(struct uart_port *uport, /* baud rate */ baud = uart_get_baud_rate(uport, termios, old, 300, 8000000); - ret = port->dev_data->set_rate(uport, baud); + ret = geni_serial_set_rate(uport, baud); if (ret) return; @@ -1711,27 +1667,8 @@ static int geni_serial_resources_off(struct uart_port *uport) return 0; } -static int geni_serial_resource_state(struct uart_port *uport, bool power_on) -{ - return power_on ? geni_serial_resources_on(uport) : geni_serial_resources_off(uport); -} - -static int geni_serial_pwr_init(struct uart_port *uport) -{ - struct qcom_geni_serial_port *port = to_dev_port(uport); - int ret; - - ret = dev_pm_domain_attach_list(port->se.dev, - &port->dev_data->pd_data, &port->pd_list); - if (ret <= 0) - return -EINVAL; - - return 0; -} - -static int geni_serial_resource_init(struct uart_port *uport) +static int geni_serial_resource_init(struct qcom_geni_serial_port *port) { - struct qcom_geni_serial_port *port = to_dev_port(uport); int ret; port->se.clk = devm_clk_get(port->se.dev, "se"); @@ -1776,10 +1713,10 @@ static void qcom_geni_serial_pm(struct uart_port *uport, old_state = UART_PM_STATE_OFF; if (new_state == UART_PM_STATE_ON && old_state == UART_PM_STATE_OFF) - pm_runtime_resume_and_get(uport->dev); + geni_serial_resources_on(uport); else if (new_state == UART_PM_STATE_OFF && old_state == UART_PM_STATE_ON) - pm_runtime_put_sync(uport->dev); + geni_serial_resources_off(uport); } @@ -1882,16 +1819,13 @@ static int qcom_geni_serial_probe(struct platform_device *pdev) port->se.dev = &pdev->dev; port->se.wrapper = dev_get_drvdata(pdev->dev.parent); - ret = port->dev_data->resources_init(uport); + ret = geni_serial_resource_init(port); if (ret) return ret; res = platform_get_resource(pdev, IORESOURCE_MEM, 0); - if (!res) { - ret = -EINVAL; - goto error; - } - + if (!res) + return -EINVAL; uport->mapbase = res->start; uport->rs485_config = qcom_geni_rs485_config; @@ -1903,26 +1837,19 @@ static int qcom_geni_serial_probe(struct platform_device *pdev) if (!data->console) { port->rx_buf = devm_kzalloc(uport->dev, DMA_RX_BUF_SIZE, GFP_KERNEL); - if (!port->rx_buf) { - ret = -ENOMEM; - goto error; - } + if (!port->rx_buf) + return -ENOMEM; } port->name = devm_kasprintf(uport->dev, GFP_KERNEL, "qcom_geni_serial_%s%d", uart_console(uport) ? "console" : "uart", uport->line); - if (!port->name) { - ret = -ENOMEM; - goto error; - } + if (!port->name) + return -ENOMEM; irq = platform_get_irq(pdev, 0); - if (irq < 0) { - ret = irq; - goto error; - } - + if (irq < 0) + return irq; uport->irq = irq; uport->has_sysrq = IS_ENABLED(CONFIG_SERIAL_QCOM_GENI_CONSOLE); @@ -1944,18 +1871,16 @@ static int qcom_geni_serial_probe(struct platform_device *pdev) IRQF_TRIGGER_HIGH, port->name, uport); if (ret) { dev_err(uport->dev, "Failed to get IRQ ret %d\n", ret); - goto error; + return ret; } ret = uart_get_rs485_mode(uport); if (ret) return ret; - devm_pm_runtime_enable(port->se.dev); - ret = uart_add_one_port(drv, uport); if (ret) - goto error; + return ret; if (port->wakeup_irq > 0) { device_init_wakeup(&pdev->dev, true); @@ -1965,15 +1890,11 @@ static int qcom_geni_serial_probe(struct platform_device *pdev) device_init_wakeup(&pdev->dev, false); ida_free(&port_ida, uport->line); uart_remove_one_port(drv, uport); - goto error; + return ret; } } return 0; - -error: - dev_pm_domain_detach_list(port->pd_list); - return ret; } static void qcom_geni_serial_remove(struct platform_device *pdev) @@ -1986,31 +1907,6 @@ static void qcom_geni_serial_remove(struct platform_device *pdev) device_init_wakeup(&pdev->dev, false); ida_free(&port_ida, uport->line); uart_remove_one_port(drv, &port->uport); - dev_pm_domain_detach_list(port->pd_list); -} - -static int __maybe_unused qcom_geni_serial_runtime_suspend(struct device *dev) -{ - struct qcom_geni_serial_port *port = dev_get_drvdata(dev); - struct uart_port *uport = &port->uport; - int ret = 0; - - if (port->dev_data->power_state) - ret = port->dev_data->power_state(uport, false); - - return ret; -} - -static int __maybe_unused qcom_geni_serial_runtime_resume(struct device *dev) -{ - struct qcom_geni_serial_port *port = dev_get_drvdata(dev); - struct uart_port *uport = &port->uport; - int ret = 0; - - if (port->dev_data->power_state) - ret = port->dev_data->power_state(uport, true); - - return ret; } static int qcom_geni_serial_suspend(struct device *dev) @@ -2048,46 +1944,14 @@ static int qcom_geni_serial_resume(struct device *dev) static const struct qcom_geni_device_data qcom_geni_console_data = { .console = true, .mode = GENI_SE_FIFO, - .resources_init = geni_serial_resource_init, - .set_rate = geni_serial_set_rate, - .power_state = geni_serial_resource_state, }; static const struct qcom_geni_device_data qcom_geni_uart_data = { .console = false, .mode = GENI_SE_DMA, - .resources_init = geni_serial_resource_init, - .set_rate = geni_serial_set_rate, - .power_state = geni_serial_resource_state, -}; - -static const struct qcom_geni_device_data sa8255p_qcom_geni_console_data = { - .console = true, - .mode = GENI_SE_FIFO, - .pd_data = { - .pd_flags = PD_FLAG_DEV_LINK_ON, - .pd_names = (const char*[]) { "power", "perf" }, - .num_pd_names = 2, - }, - .resources_init = geni_serial_pwr_init, - .set_rate = geni_serial_set_level, -}; - -static const struct qcom_geni_device_data sa8255p_qcom_geni_uart_data = { - .console = false, - .mode = GENI_SE_DMA, - .pd_data = { - .pd_flags = PD_FLAG_DEV_LINK_ON, - .pd_names = (const char*[]) { "power", "perf" }, - .num_pd_names = 2, - }, - .resources_init = geni_serial_pwr_init, - .set_rate = geni_serial_set_level, }; static const struct dev_pm_ops qcom_geni_serial_pm_ops = { - SET_RUNTIME_PM_OPS(qcom_geni_serial_runtime_suspend, - qcom_geni_serial_runtime_resume, NULL) SYSTEM_SLEEP_PM_OPS(qcom_geni_serial_suspend, qcom_geni_serial_resume) }; @@ -2096,18 +1960,10 @@ static const struct of_device_id qcom_geni_serial_match_table[] = { .compatible = "qcom,geni-debug-uart", .data = &qcom_geni_console_data, }, - { - .compatible = "qcom,sa8255p-geni-debug-uart", - .data = &sa8255p_qcom_geni_console_data, - }, { .compatible = "qcom,geni-uart", .data = &qcom_geni_uart_data, }, - { - .compatible = "qcom,sa8255p-geni-uart", - .data = &sa8255p_qcom_geni_uart_data, - }, {} }; MODULE_DEVICE_TABLE(of, qcom_geni_serial_match_table);