From: Girish Mahadevan <girishm@xxxxxxxxxxxxxx>
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 <girishm@xxxxxxxxxxxxxx>
Signed-off-by: Mohammed Khajapasha <mkhaja@xxxxxxxxxxxxxx>
Signed-off-by: Karthikeyan Ramasubramanian <kramasub@xxxxxxxxxxxxxx>
---
.../devicetree/bindings/soc/qcom/qcom,geni-se.txt | 2 +-
drivers/tty/serial/qcom_geni_serial.c | 261 ++++++++++++++++++---
2 files changed, 231 insertions(+), 32 deletions(-)
diff --git a/Documentation/devicetree/bindings/soc/qcom/qcom,geni-se.txt b/Documentation/devicetree/bindings/soc/qcom/qcom,geni-se.txt
index d330c73..a9eeca2 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 c62e17c..29ec343 100644
--- a/drivers/tty/serial/qcom_geni_serial.c
+++ b/drivers/tty/serial/qcom_geni_serial.c
@@ -17,6 +17,7 @@
#include <linux/tty_flip.h>
/* 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 void qcom_geni_serial_cons_pm(struct uart_port *uport,
.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 int __maybe_unused qcom_geni_serial_sys_resume_noirq(struct device *dev)
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 = 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)
+ 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);
--
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