1 files changed, 353 insertions, 0 deletions

diff --git a/drivers/tty/serial/8250/8250_ingenic.c b/drivers/tty/serial/8250/8250_ingenic.c
new file mode 100644
index 000000000..2b2f5d8d2
--- /dev/null
+++ b/drivers/tty/serial/8250/8250_ingenic.c
@@ -0,0 +1,353 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright (C) 2010 Lars-Peter Clausen <lars@metafoo.de>
+ * Copyright (C) 2015 Imagination Technologies
+ *
+ * Ingenic SoC UART support
+ */
+
+#include <linux/clk.h>
+#include <linux/console.h>
+#include <linux/io.h>
+#include <linux/libfdt.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_fdt.h>
+#include <linux/of_device.h>
+#include <linux/platform_device.h>
+#include <linux/serial_8250.h>
+#include <linux/serial_core.h>
+#include <linux/serial_reg.h>
+
+#include "8250.h"
+
+/** ingenic_uart_config: SOC specific config data. */
+struct ingenic_uart_config {
+	int tx_loadsz;
+	int fifosize;
+};
+
+struct ingenic_uart_data {
+	struct clk	*clk_module;
+	struct clk	*clk_baud;
+	int		line;
+};
+
+static const struct of_device_id of_match[];
+
+#define UART_FCR_UME	BIT(4)
+
+#define UART_MCR_MDCE	BIT(7)
+#define UART_MCR_FCM	BIT(6)
+
+static struct earlycon_device *early_device;
+
+static uint8_t early_in(struct uart_port *port, int offset)
+{
+	return readl(port->membase + (offset << 2));
+}
+
+static void early_out(struct uart_port *port, int offset, uint8_t value)
+{
+	writel(value, port->membase + (offset << 2));
+}
+
+static void ingenic_early_console_putc(struct uart_port *port, unsigned char c)
+{
+	u16 lsr;
+
+	do {
+		lsr = early_in(port, UART_LSR);
+	} while ((lsr & UART_LSR_TEMT) == 0);
+
+	early_out(port, UART_TX, c);
+}
+
+static void ingenic_early_console_write(struct console *console,
+					      const char *s, unsigned int count)
+{
+	uart_console_write(&early_device->port, s, count,
+			   ingenic_early_console_putc);
+}
+
+static void __init ingenic_early_console_setup_clock(struct earlycon_device *dev)
+{
+	void *fdt = initial_boot_params;
+	const __be32 *prop;
+	int offset;
+
+	offset = fdt_path_offset(fdt, "/ext");
+	if (offset < 0)
+		return;
+
+	prop = fdt_getprop(fdt, offset, "clock-frequency", NULL);
+	if (!prop)
+		return;
+
+	dev->port.uartclk = be32_to_cpup(prop);
+}
+
+static int __init ingenic_early_console_setup(struct earlycon_device *dev,
+					      const char *opt)
+{
+	struct uart_port *port = &dev->port;
+	unsigned int divisor;
+	int baud = 115200;
+
+	if (!dev->port.membase)
+		return -ENODEV;
+
+	if (opt) {
+		unsigned int parity, bits, flow; /* unused for now */
+
+		uart_parse_options(opt, &baud, &parity, &bits, &flow);
+	}
+
+	ingenic_early_console_setup_clock(dev);
+
+	if (dev->baud)
+		baud = dev->baud;
+	divisor = DIV_ROUND_CLOSEST(port->uartclk, 16 * baud);
+
+	early_out(port, UART_IER, 0);
+	early_out(port, UART_LCR, UART_LCR_DLAB | UART_LCR_WLEN8);
+	early_out(port, UART_DLL, 0);
+	early_out(port, UART_DLM, 0);
+	early_out(port, UART_LCR, UART_LCR_WLEN8);
+	early_out(port, UART_FCR, UART_FCR_UME | UART_FCR_CLEAR_XMIT |
+			UART_FCR_CLEAR_RCVR | UART_FCR_ENABLE_FIFO);
+	early_out(port, UART_MCR, UART_MCR_RTS | UART_MCR_DTR);
+
+	early_out(port, UART_LCR, UART_LCR_DLAB | UART_LCR_WLEN8);
+	early_out(port, UART_DLL, divisor & 0xff);
+	early_out(port, UART_DLM, (divisor >> 8) & 0xff);
+	early_out(port, UART_LCR, UART_LCR_WLEN8);
+
+	early_device = dev;
+	dev->con->write = ingenic_early_console_write;
+
+	return 0;
+}
+
+OF_EARLYCON_DECLARE(jz4740_uart, "ingenic,jz4740-uart",
+		    ingenic_early_console_setup);
+
+OF_EARLYCON_DECLARE(jz4770_uart, "ingenic,jz4770-uart",
+		    ingenic_early_console_setup);
+
+OF_EARLYCON_DECLARE(jz4775_uart, "ingenic,jz4775-uart",
+		    ingenic_early_console_setup);
+
+OF_EARLYCON_DECLARE(jz4780_uart, "ingenic,jz4780-uart",
+		    ingenic_early_console_setup);
+
+OF_EARLYCON_DECLARE(x1000_uart, "ingenic,x1000-uart",
+		    ingenic_early_console_setup);
+
+static void ingenic_uart_serial_out(struct uart_port *p, int offset, int value)
+{
+	int ier;
+
+	switch (offset) {
+	case UART_FCR:
+		/* UART module enable */
+		value |= UART_FCR_UME;
+		break;
+
+	case UART_IER:
+		/*
+		 * Enable receive timeout interrupt with the receive line
+		 * status interrupt.
+		 */
+		value |= (value & 0x4) << 2;
+		break;
+
+	case UART_MCR:
+		/*
+		 * If we have enabled modem status IRQs we should enable
+		 * modem mode.
+		 */
+		ier = p->serial_in(p, UART_IER);
+
+		if (ier & UART_IER_MSI)
+			value |= UART_MCR_MDCE | UART_MCR_FCM;
+		else
+			value &= ~(UART_MCR_MDCE | UART_MCR_FCM);
+		break;
+
+	default:
+		break;
+	}
+
+	writeb(value, p->membase + (offset << p->regshift));
+}
+
+static unsigned int ingenic_uart_serial_in(struct uart_port *p, int offset)
+{
+	unsigned int value;
+
+	value = readb(p->membase + (offset << p->regshift));
+
+	/* Hide non-16550 compliant bits from higher levels */
+	switch (offset) {
+	case UART_FCR:
+		value &= ~UART_FCR_UME;
+		break;
+
+	case UART_MCR:
+		value &= ~(UART_MCR_MDCE | UART_MCR_FCM);
+		break;
+
+	default:
+		break;
+	}
+	return value;
+}
+
+static int ingenic_uart_probe(struct platform_device *pdev)
+{
+	struct uart_8250_port uart = {};
+	struct ingenic_uart_data *data;
+	const struct ingenic_uart_config *cdata;
+	struct resource *regs;
+	int irq, err, line;
+
+	cdata = of_device_get_match_data(&pdev->dev);
+	if (!cdata) {
+		dev_err(&pdev->dev, "Error: No device match found\n");
+		return -ENODEV;
+	}
+
+	irq = platform_get_irq(pdev, 0);
+	if (irq < 0)
+		return irq;
+
+	regs = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (!regs) {
+		dev_err(&pdev->dev, "no registers defined\n");
+		return -EINVAL;
+	}
+
+	data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL);
+	if (!data)
+		return -ENOMEM;
+
+	spin_lock_init(&uart.port.lock);
+	uart.port.type = PORT_16550A;
+	uart.port.flags = UPF_SKIP_TEST | UPF_IOREMAP | UPF_FIXED_TYPE;
+	uart.port.iotype = UPIO_MEM;
+	uart.port.mapbase = regs->start;
+	uart.port.regshift = 2;
+	uart.port.serial_out = ingenic_uart_serial_out;
+	uart.port.serial_in = ingenic_uart_serial_in;
+	uart.port.irq = irq;
+	uart.port.dev = &pdev->dev;
+	uart.port.fifosize = cdata->fifosize;
+	uart.tx_loadsz = cdata->tx_loadsz;
+	uart.capabilities = UART_CAP_FIFO | UART_CAP_RTOIE;
+
+	/* Check for a fixed line number */
+	line = of_alias_get_id(pdev->dev.of_node, "serial");
+	if (line >= 0)
+		uart.port.line = line;
+
+	uart.port.membase = devm_ioremap(&pdev->dev, regs->start,
+					 resource_size(regs));
+	if (!uart.port.membase)
+		return -ENOMEM;
+
+	data->clk_module = devm_clk_get(&pdev->dev, "module");
+	if (IS_ERR(data->clk_module))
+		return dev_err_probe(&pdev->dev, PTR_ERR(data->clk_module),
+				     "unable to get module clock\n");
+
+	data->clk_baud = devm_clk_get(&pdev->dev, "baud");
+	if (IS_ERR(data->clk_baud))
+		return dev_err_probe(&pdev->dev, PTR_ERR(data->clk_baud),
+				     "unable to get baud clock\n");
+
+	err = clk_prepare_enable(data->clk_module);
+	if (err) {
+		dev_err(&pdev->dev, "could not enable module clock: %d\n", err);
+		goto out;
+	}
+
+	err = clk_prepare_enable(data->clk_baud);
+	if (err) {
+		dev_err(&pdev->dev, "could not enable baud clock: %d\n", err);
+		goto out_disable_moduleclk;
+	}
+	uart.port.uartclk = clk_get_rate(data->clk_baud);
+
+	data->line = serial8250_register_8250_port(&uart);
+	if (data->line < 0) {
+		err = data->line;
+		goto out_disable_baudclk;
+	}
+
+	platform_set_drvdata(pdev, data);
+	return 0;
+
+out_disable_baudclk:
+	clk_disable_unprepare(data->clk_baud);
+out_disable_moduleclk:
+	clk_disable_unprepare(data->clk_module);
+out:
+	return err;
+}
+
+static int ingenic_uart_remove(struct platform_device *pdev)
+{
+	struct ingenic_uart_data *data = platform_get_drvdata(pdev);
+
+	serial8250_unregister_port(data->line);
+	clk_disable_unprepare(data->clk_module);
+	clk_disable_unprepare(data->clk_baud);
+	return 0;
+}
+
+static const struct ingenic_uart_config jz4740_uart_config = {
+	.tx_loadsz = 8,
+	.fifosize = 16,
+};
+
+static const struct ingenic_uart_config jz4760_uart_config = {
+	.tx_loadsz = 16,
+	.fifosize = 32,
+};
+
+static const struct ingenic_uart_config jz4780_uart_config = {
+	.tx_loadsz = 32,
+	.fifosize = 64,
+};
+
+static const struct ingenic_uart_config x1000_uart_config = {
+	.tx_loadsz = 32,
+	.fifosize = 64,
+};
+
+static const struct of_device_id of_match[] = {
+	{ .compatible = "ingenic,jz4740-uart", .data = &jz4740_uart_config },
+	{ .compatible = "ingenic,jz4760-uart", .data = &jz4760_uart_config },
+	{ .compatible = "ingenic,jz4770-uart", .data = &jz4760_uart_config },
+	{ .compatible = "ingenic,jz4775-uart", .data = &jz4760_uart_config },
+	{ .compatible = "ingenic,jz4780-uart", .data = &jz4780_uart_config },
+	{ .compatible = "ingenic,x1000-uart", .data = &x1000_uart_config },
+	{ /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, of_match);
+
+static struct platform_driver ingenic_uart_platform_driver = {
+	.driver = {
+		.name		= "ingenic-uart",
+		.of_match_table	= of_match,
+	},
+	.probe			= ingenic_uart_probe,
+	.remove			= ingenic_uart_remove,
+};
+
+module_platform_driver(ingenic_uart_platform_driver);
+
+MODULE_AUTHOR("Paul Burton");
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("Ingenic SoC UART driver");