From 8a8a66a1a18a1dbd213bee460bcedb1361abc7ff Mon Sep 17 00:00:00 2001 From: Girish Mahadevan Date: Fri, 13 Jul 2018 16:17:35 -0600 Subject: [PATCH] tty: serial: qcom_geni_serial: Add support for flow control Add support for flow control functionality in the GENI serial driver and also support for non-console higher baud rate(upto 4Mbps) usecases. Signed-off-by: Girish Mahadevan Signed-off-by: Mohammed Khajapasha Signed-off-by: Karthikeyan Ramasubramanian Signed-off-by: Greg Kroah-Hartman --- .../bindings/soc/qcom/qcom,geni-se.txt | 2 +- drivers/tty/serial/qcom_geni_serial.c | 263 +++++++++++++++--- 2 files changed, 232 insertions(+), 33 deletions(-) diff --git a/Documentation/devicetree/bindings/soc/qcom/qcom,geni-se.txt b/Documentation/devicetree/bindings/soc/qcom/qcom,geni-se.txt index d330c73de9a2..a9eeca28f03e 100644 --- a/Documentation/devicetree/bindings/soc/qcom/qcom,geni-se.txt +++ b/Documentation/devicetree/bindings/soc/qcom/qcom,geni-se.txt @@ -46,7 +46,7 @@ Child nodes should conform to I2C bus binding as described in i2c.txt. Qualcomm Technologies Inc. GENI Serial Engine based UART Controller Required properties: -- compatible: Must be "qcom,geni-debug-uart". +- compatible: Must be "qcom,geni-debug-uart" or "qcom,geni-uart". - reg: Must contain UART register location and length. - interrupts: Must contain UART core interrupts. - clock-names: Must contain "se". diff --git a/drivers/tty/serial/qcom_geni_serial.c b/drivers/tty/serial/qcom_geni_serial.c index c62e17c85f57..29ec34387246 100644 --- a/drivers/tty/serial/qcom_geni_serial.c +++ b/drivers/tty/serial/qcom_geni_serial.c @@ -17,6 +17,7 @@ #include /* UART specific GENI registers */ +#define SE_UART_LOOPBACK_CFG 0x22c #define SE_UART_TX_TRANS_CFG 0x25c #define SE_UART_TX_WORD_LEN 0x268 #define SE_UART_TX_STOP_BIT_LEN 0x26c @@ -26,6 +27,7 @@ #define SE_UART_RX_STALE_CNT 0x294 #define SE_UART_TX_PARITY_CFG 0x2a4 #define SE_UART_RX_PARITY_CFG 0x2a8 +#define SE_UART_MANUAL_RFR 0x2ac /* SE_UART_TRANS_CFG */ #define UART_TX_PAR_EN BIT(0) @@ -62,6 +64,11 @@ #define PAR_SPACE 0x10 #define PAR_MARK 0x11 +/* SE_UART_MANUAL_RFR register fields */ +#define UART_MANUAL_RFR_EN BIT(31) +#define UART_RFR_NOT_READY BIT(1) +#define UART_RFR_READY BIT(0) + /* UART M_CMD OP codes */ #define UART_START_TX 0x1 #define UART_START_BREAK 0x4 @@ -74,10 +81,12 @@ #define STALE_TIMEOUT 16 #define DEFAULT_BITS_PER_CHAR 10 #define GENI_UART_CONS_PORTS 1 +#define GENI_UART_PORTS 3 #define DEF_FIFO_DEPTH_WORDS 16 #define DEF_TX_WM 2 #define DEF_FIFO_WIDTH_BITS 32 #define UART_CONSOLE_RX_WM 2 +#define MAX_LOOPBACK_CFG 3 #ifdef CONFIG_CONSOLE_POLL #define RX_BYTES_PW 1 @@ -101,22 +110,81 @@ struct qcom_geni_serial_port { unsigned int baud; unsigned int tx_bytes_pw; unsigned int rx_bytes_pw; + u32 *rx_fifo; + u32 loopback; bool brk; }; static const struct uart_ops qcom_geni_console_pops; +static const struct uart_ops qcom_geni_uart_pops; static struct uart_driver qcom_geni_console_driver; +static struct uart_driver qcom_geni_uart_driver; static int handle_rx_console(struct uart_port *uport, u32 bytes, bool drop); +static int handle_rx_uart(struct uart_port *uport, u32 bytes, bool drop); static unsigned int qcom_geni_serial_tx_empty(struct uart_port *port); static void qcom_geni_serial_stop_rx(struct uart_port *uport); static const unsigned long root_freq[] = {7372800, 14745600, 19200000, 29491200, 32000000, 48000000, 64000000, 80000000, - 96000000, 100000000}; + 96000000, 100000000, 102400000, + 112000000, 120000000, 128000000}; #define to_dev_port(ptr, member) \ container_of(ptr, struct qcom_geni_serial_port, member) +static struct qcom_geni_serial_port qcom_geni_uart_ports[GENI_UART_PORTS] = { + [0] = { + .uport = { + .iotype = UPIO_MEM, + .ops = &qcom_geni_uart_pops, + .flags = UPF_BOOT_AUTOCONF, + .line = 0, + }, + }, + [1] = { + .uport = { + .iotype = UPIO_MEM, + .ops = &qcom_geni_uart_pops, + .flags = UPF_BOOT_AUTOCONF, + .line = 1, + }, + }, + [2] = { + .uport = { + .iotype = UPIO_MEM, + .ops = &qcom_geni_uart_pops, + .flags = UPF_BOOT_AUTOCONF, + .line = 2, + }, + }, +}; + +static ssize_t loopback_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct platform_device *pdev = to_platform_device(dev); + struct qcom_geni_serial_port *port = platform_get_drvdata(pdev); + + return snprintf(buf, sizeof(u32), "%d\n", port->loopback); +} + +static ssize_t loopback_store(struct device *dev, + struct device_attribute *attr, const char *buf, + size_t size) +{ + struct platform_device *pdev = to_platform_device(dev); + struct qcom_geni_serial_port *port = platform_get_drvdata(pdev); + u32 loopback; + + if (kstrtoint(buf, 0, &loopback) || loopback > MAX_LOOPBACK_CFG) { + dev_err(dev, "Invalid input\n"); + return -EINVAL; + } + port->loopback = loopback; + return size; +} +static DEVICE_ATTR_RW(loopback); + static struct qcom_geni_serial_port qcom_geni_console_port = { .uport = { .iotype = UPIO_MEM, @@ -148,14 +216,33 @@ static void qcom_geni_serial_config_port(struct uart_port *uport, int cfg_flags) } } -static unsigned int qcom_geni_cons_get_mctrl(struct uart_port *uport) +static unsigned int qcom_geni_serial_get_mctrl(struct uart_port *uport) { - return TIOCM_DSR | TIOCM_CAR | TIOCM_CTS; + unsigned int mctrl = TIOCM_DSR | TIOCM_CAR; + u32 geni_ios; + + if (uart_console(uport) || !uart_cts_enabled(uport)) { + mctrl |= TIOCM_CTS; + } else { + geni_ios = readl_relaxed(uport->membase + SE_GENI_IOS); + if (!(geni_ios & IO2_DATA_IN)) + mctrl |= TIOCM_CTS; + } + + return mctrl; } -static void qcom_geni_cons_set_mctrl(struct uart_port *uport, +static void qcom_geni_serial_set_mctrl(struct uart_port *uport, unsigned int mctrl) { + u32 uart_manual_rfr = 0; + + if (uart_console(uport) || !uart_cts_enabled(uport)) + return; + + if (!(mctrl & TIOCM_RTS)) + uart_manual_rfr = UART_MANUAL_RFR_EN | UART_RFR_NOT_READY; + writel_relaxed(uart_manual_rfr, uport->membase + SE_UART_MANUAL_RFR); } static const char *qcom_geni_serial_get_type(struct uart_port *uport) @@ -163,11 +250,16 @@ static const char *qcom_geni_serial_get_type(struct uart_port *uport) return "MSM"; } -static struct qcom_geni_serial_port *get_port_from_line(int line) +static struct qcom_geni_serial_port *get_port_from_line(int line, bool console) { - if (line < 0 || line >= GENI_UART_CONS_PORTS) + struct qcom_geni_serial_port *port; + int nr_ports = console ? GENI_UART_CONS_PORTS : GENI_UART_PORTS; + + if (line < 0 || line >= nr_ports) return ERR_PTR(-ENXIO); - return &qcom_geni_console_port; + + port = console ? &qcom_geni_console_port : &qcom_geni_uart_ports[line]; + return port; } static bool qcom_geni_serial_poll_bit(struct uart_port *uport, @@ -346,7 +438,7 @@ static void qcom_geni_serial_console_write(struct console *co, const char *s, WARN_ON(co->index < 0 || co->index >= GENI_UART_CONS_PORTS); - port = get_port_from_line(co->index); + port = get_port_from_line(co->index, true); if (IS_ERR(port)) return; @@ -420,6 +512,32 @@ static int handle_rx_console(struct uart_port *uport, u32 bytes, bool drop) #endif /* CONFIG_SERIAL_QCOM_GENI_CONSOLE */ +static int handle_rx_uart(struct uart_port *uport, u32 bytes, bool drop) +{ + unsigned char *buf; + struct tty_port *tport; + struct qcom_geni_serial_port *port = to_dev_port(uport, uport); + u32 num_bytes_pw = port->tx_fifo_width / BITS_PER_BYTE; + u32 words = ALIGN(bytes, num_bytes_pw) / num_bytes_pw; + int ret; + + tport = &uport->state->port; + ioread32_rep(uport->membase + SE_GENI_RX_FIFOn, port->rx_fifo, words); + if (drop) + return 0; + + buf = (unsigned char *)port->rx_fifo; + ret = tty_insert_flip_string(tport, buf, bytes); + if (ret != bytes) { + dev_err(uport->dev, "%s:Unable to push data ret %d_bytes %d\n", + __func__, ret, bytes); + WARN_ON_ONCE(1); + } + uport->icount.rx += ret; + tty_flip_buffer_push(tport); + return ret; +} + static void qcom_geni_serial_start_tx(struct uart_port *uport) { u32 irq_en; @@ -586,6 +704,7 @@ static void qcom_geni_serial_handle_tx(struct uart_port *uport) u32 status; unsigned int chunk; int tail; + u32 irq_en; chunk = uart_circ_chars_pending(xmit); status = readl_relaxed(uport->membase + SE_GENI_TX_FIFO_STATUS); @@ -595,6 +714,13 @@ static void qcom_geni_serial_handle_tx(struct uart_port *uport) goto out_write_wakeup; } + if (!uart_console(uport)) { + irq_en = readl_relaxed(uport->membase + SE_GENI_M_IRQ_EN); + irq_en &= ~(M_TX_FIFO_WATERMARK_EN); + writel_relaxed(0, uport->membase + SE_GENI_TX_WATERMARK_REG); + writel_relaxed(irq_en, uport->membase + SE_GENI_M_IRQ_EN); + } + avail = (port->tx_fifo_depth - port->tx_wm) * port->tx_bytes_pw; tail = xmit->tail; chunk = min3((size_t)chunk, (size_t)(UART_XMIT_SIZE - tail), avail); @@ -623,7 +749,8 @@ static void qcom_geni_serial_handle_tx(struct uart_port *uport) } xmit->tail = tail & (UART_XMIT_SIZE - 1); - qcom_geni_serial_poll_tx_done(uport); + if (uart_console(uport)) + qcom_geni_serial_poll_tx_done(uport); out_write_wakeup: if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) uart_write_wakeup(uport); @@ -710,7 +837,8 @@ static void qcom_geni_serial_shutdown(struct uart_port *uport) unsigned long flags; /* Stop the console before stopping the current tx */ - console_stop(uport->cons); + if (uart_console(uport)) + console_stop(uport->cons); free_irq(uport->irq, uport); spin_lock_irqsave(&uport->lock, flags); @@ -731,13 +859,20 @@ static int qcom_geni_serial_port_setup(struct uart_port *uport) * it else we could end up in data loss scenarios. */ port->xfer_mode = GENI_SE_FIFO; - qcom_geni_serial_poll_tx_done(uport); + if (uart_console(uport)) + qcom_geni_serial_poll_tx_done(uport); geni_se_config_packing(&port->se, BITS_PER_BYTE, port->tx_bytes_pw, false, true, false); geni_se_config_packing(&port->se, BITS_PER_BYTE, port->rx_bytes_pw, false, false, true); geni_se_init(&port->se, port->rx_wm, port->rx_rfr); geni_se_select_mode(&port->se, port->xfer_mode); + if (!uart_console(uport)) { + port->rx_fifo = devm_kzalloc(uport->dev, + port->rx_fifo_depth * sizeof(u32), GFP_KERNEL); + if (!port->rx_fifo) + return -ENOMEM; + } port->setup = true; return 0; } @@ -749,8 +884,13 @@ static int qcom_geni_serial_startup(struct uart_port *uport) struct qcom_geni_serial_port *port = to_dev_port(uport, uport); scnprintf(port->name, sizeof(port->name), - "qcom_serial_geni%d", uport->line); + "qcom_serial_%s%d", + (uart_console(uport) ? "console" : "uart"), uport->line); + if (!uart_console(uport)) { + port->tx_bytes_pw = 4; + port->rx_bytes_pw = RX_BYTES_PW; + } proto = geni_se_read_proto(&port->se); if (proto != GENI_SE_UART) { dev_err(uport->dev, "Invalid FW loaded, proto: %d\n", proto); @@ -886,6 +1026,9 @@ static void qcom_geni_serial_set_termios(struct uart_port *uport, if (baud) uart_update_timeout(uport, termios->c_cflag, baud); + if (!uart_console(uport)) + writel_relaxed(port->loopback, + uport->membase + SE_UART_LOOPBACK_CFG); writel_relaxed(tx_trans_cfg, uport->membase + SE_UART_TX_TRANS_CFG); writel_relaxed(tx_parity_cfg, uport->membase + SE_UART_TX_PARITY_CFG); writel_relaxed(rx_trans_cfg, uport->membase + SE_UART_RX_TRANS_CFG); @@ -917,7 +1060,7 @@ static int __init qcom_geni_console_setup(struct console *co, char *options) if (co->index >= GENI_UART_CONS_PORTS || co->index < 0) return -ENXIO; - port = get_port_from_line(co->index); + port = get_port_from_line(co->index, true); if (IS_ERR(port)) { pr_err("Invalid line %d\n", co->index); return PTR_ERR(port); @@ -1048,16 +1191,23 @@ static void console_unregister(struct uart_driver *drv) } #endif /* CONFIG_SERIAL_QCOM_GENI_CONSOLE */ -static void qcom_geni_serial_cons_pm(struct uart_port *uport, +static struct uart_driver qcom_geni_uart_driver = { + .owner = THIS_MODULE, + .driver_name = "qcom_geni_uart", + .dev_name = "ttyHS", + .nr = GENI_UART_PORTS, +}; + +static void qcom_geni_serial_pm(struct uart_port *uport, unsigned int new_state, unsigned int old_state) { struct qcom_geni_serial_port *port = to_dev_port(uport, uport); - if (unlikely(!uart_console(uport))) - return; - if (new_state == UART_PM_STATE_ON && old_state == UART_PM_STATE_OFF) geni_se_resources_on(&port->se); + else if (!uart_console(uport) && (new_state == UART_PM_STATE_ON && + old_state == UART_PM_STATE_UNDEFINED)) + geni_se_resources_on(&port->se); else if (new_state == UART_PM_STATE_OFF && old_state == UART_PM_STATE_ON) geni_se_resources_off(&port->se); @@ -1074,13 +1224,29 @@ static const struct uart_ops qcom_geni_console_pops = { .config_port = qcom_geni_serial_config_port, .shutdown = qcom_geni_serial_shutdown, .type = qcom_geni_serial_get_type, - .set_mctrl = qcom_geni_cons_set_mctrl, - .get_mctrl = qcom_geni_cons_get_mctrl, + .set_mctrl = qcom_geni_serial_set_mctrl, + .get_mctrl = qcom_geni_serial_get_mctrl, #ifdef CONFIG_CONSOLE_POLL .poll_get_char = qcom_geni_serial_get_char, .poll_put_char = qcom_geni_serial_poll_put_char, #endif - .pm = qcom_geni_serial_cons_pm, + .pm = qcom_geni_serial_pm, +}; + +static const struct uart_ops qcom_geni_uart_pops = { + .tx_empty = qcom_geni_serial_tx_empty, + .stop_tx = qcom_geni_serial_stop_tx, + .start_tx = qcom_geni_serial_start_tx, + .stop_rx = qcom_geni_serial_stop_rx, + .set_termios = qcom_geni_serial_set_termios, + .startup = qcom_geni_serial_startup, + .request_port = qcom_geni_serial_request_port, + .config_port = qcom_geni_serial_config_port, + .shutdown = qcom_geni_serial_shutdown, + .type = qcom_geni_serial_get_type, + .set_mctrl = qcom_geni_serial_set_mctrl, + .get_mctrl = qcom_geni_serial_get_mctrl, + .pm = qcom_geni_serial_pm, }; static int qcom_geni_serial_probe(struct platform_device *pdev) @@ -1091,13 +1257,23 @@ static int qcom_geni_serial_probe(struct platform_device *pdev) struct uart_port *uport; struct resource *res; int irq; + bool console = false; + struct uart_driver *drv; - if (pdev->dev.of_node) - line = of_alias_get_id(pdev->dev.of_node, "serial"); + if (of_device_is_compatible(pdev->dev.of_node, "qcom,geni-debug-uart")) + console = true; - if (line < 0 || line >= GENI_UART_CONS_PORTS) - return -ENXIO; - port = get_port_from_line(line); + if (pdev->dev.of_node) { + if (console) { + drv = &qcom_geni_console_driver; + line = of_alias_get_id(pdev->dev.of_node, "serial"); + } else { + drv = &qcom_geni_uart_driver; + line = of_alias_get_id(pdev->dev.of_node, "hsuart"); + } + } + + port = get_port_from_line(line, console); if (IS_ERR(port)) { dev_err(&pdev->dev, "Invalid line %d\n", line); return PTR_ERR(port); @@ -1134,10 +1310,12 @@ static int qcom_geni_serial_probe(struct platform_device *pdev) } uport->irq = irq; - uport->private_data = &qcom_geni_console_driver; + uport->private_data = drv; platform_set_drvdata(pdev, port); - port->handle_rx = handle_rx_console; - return uart_add_one_port(&qcom_geni_console_driver, uport); + port->handle_rx = console ? handle_rx_console : handle_rx_uart; + if (!console) + device_create_file(uport->dev, &dev_attr_loopback); + return uart_add_one_port(drv, uport); } static int qcom_geni_serial_remove(struct platform_device *pdev) @@ -1154,7 +1332,17 @@ static int __maybe_unused qcom_geni_serial_sys_suspend_noirq(struct device *dev) struct qcom_geni_serial_port *port = dev_get_drvdata(dev); struct uart_port *uport = &port->uport; - uart_suspend_port(uport->private_data, uport); + if (uart_console(uport)) { + uart_suspend_port(uport->private_data, uport); + } else { + struct uart_state *state = uport->state; + /* + * If the port is open, deny system suspend. + */ + if (state->pm_state == UART_PM_STATE_ON) + return -EBUSY; + } + return 0; } @@ -1163,7 +1351,8 @@ static int __maybe_unused qcom_geni_serial_sys_resume_noirq(struct device *dev) struct qcom_geni_serial_port *port = dev_get_drvdata(dev); struct uart_port *uport = &port->uport; - if (console_suspend_enabled && uport->suspended) { + if (uart_console(uport) && + console_suspend_enabled && uport->suspended) { uart_resume_port(uport->private_data, uport); /* * uart_suspend_port() invokes port shutdown which in turn @@ -1185,6 +1374,7 @@ static const struct dev_pm_ops qcom_geni_serial_pm_ops = { static const struct of_device_id qcom_geni_serial_match_table[] = { { .compatible = "qcom,geni-debug-uart", }, + { .compatible = "qcom,geni-uart", }, {} }; MODULE_DEVICE_TABLE(of, qcom_geni_serial_match_table); @@ -1207,9 +1397,17 @@ static int __init qcom_geni_serial_init(void) if (ret) return ret; - ret = platform_driver_register(&qcom_geni_serial_platform_driver); - if (ret) + ret = uart_register_driver(&qcom_geni_uart_driver); + if (ret) { console_unregister(&qcom_geni_console_driver); + return ret; + } + + ret = platform_driver_register(&qcom_geni_serial_platform_driver); + if (ret) { + console_unregister(&qcom_geni_console_driver); + uart_unregister_driver(&qcom_geni_uart_driver); + } return ret; } module_init(qcom_geni_serial_init); @@ -1218,6 +1416,7 @@ static void __exit qcom_geni_serial_exit(void) { platform_driver_unregister(&qcom_geni_serial_platform_driver); console_unregister(&qcom_geni_console_driver); + uart_unregister_driver(&qcom_geni_uart_driver); } module_exit(qcom_geni_serial_exit);