Adding upstream version 6.6.15.upstream/6.6.15

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 230 insertions, 0 deletions

diff --git a/drivers/tty/serial/8250/8250_em.c b/drivers/tty/serial/8250/8250_em.c
new file mode 100644
index 0000000000..ef5019e944
--- /dev/null
+++ b/drivers/tty/serial/8250/8250_em.c
@@ -0,0 +1,230 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Renesas Emma Mobile 8250 driver
+ *
+ *  Copyright (C) 2012 Magnus Damm
+ */
+
+#include <linux/device.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/mod_devicetable.h>
+#include <linux/serial_8250.h>
+#include <linux/serial_reg.h>
+#include <linux/platform_device.h>
+#include <linux/clk.h>
+
+#include "8250.h"
+
+#define UART_DLL_EM 9
+#define UART_DLM_EM 10
+#define UART_HCR0_EM 11
+
+/*
+ * A high value for UART_FCR_EM avoids overlapping with existing UART_*
+ * register defines. UART_FCR_EM_HW is the real HW register offset.
+ */
+#define UART_FCR_EM 0x10003
+#define UART_FCR_EM_HW 3
+
+#define UART_HCR0_EM_SW_RESET	BIT(7) /* SW Reset */
+
+struct serial8250_em_priv {
+	int line;
+};
+
+static void serial8250_em_serial_out_helper(struct uart_port *p, int offset,
+					    int value)
+{
+	switch (offset) {
+	case UART_TX: /* TX @ 0x00 */
+		writeb(value, p->membase);
+		break;
+	case UART_LCR: /* LCR @ 0x10 (+1) */
+	case UART_MCR: /* MCR @ 0x14 (+1) */
+	case UART_SCR: /* SCR @ 0x20 (+1) */
+		writel(value, p->membase + ((offset + 1) << 2));
+		break;
+	case UART_FCR_EM:
+		writel(value, p->membase + (UART_FCR_EM_HW << 2));
+		break;
+	case UART_IER: /* IER @ 0x04 */
+		value &= 0x0f; /* only 4 valid bits - not Xscale */
+		fallthrough;
+	case UART_DLL_EM: /* DLL @ 0x24 (+9) */
+	case UART_DLM_EM: /* DLM @ 0x28 (+9) */
+	case UART_HCR0_EM: /* HCR0 @ 0x2c */
+		writel(value, p->membase + (offset << 2));
+		break;
+	}
+}
+
+static unsigned int serial8250_em_serial_in(struct uart_port *p, int offset)
+{
+	switch (offset) {
+	case UART_RX: /* RX @ 0x00 */
+		return readb(p->membase);
+	case UART_LCR: /* LCR @ 0x10 (+1) */
+	case UART_MCR: /* MCR @ 0x14 (+1) */
+	case UART_LSR: /* LSR @ 0x18 (+1) */
+	case UART_MSR: /* MSR @ 0x1c (+1) */
+	case UART_SCR: /* SCR @ 0x20 (+1) */
+		return readl(p->membase + ((offset + 1) << 2));
+	case UART_FCR_EM:
+		return readl(p->membase + (UART_FCR_EM_HW << 2));
+	case UART_IER: /* IER @ 0x04 */
+	case UART_IIR: /* IIR @ 0x08 */
+	case UART_DLL_EM: /* DLL @ 0x24 (+9) */
+	case UART_DLM_EM: /* DLM @ 0x28 (+9) */
+	case UART_HCR0_EM: /* HCR0 @ 0x2c */
+		return readl(p->membase + (offset << 2));
+	}
+	return 0;
+}
+
+static void serial8250_em_reg_update(struct uart_port *p, int off, int value)
+{
+	unsigned int ier, fcr, lcr, mcr, hcr0;
+
+	ier = serial8250_em_serial_in(p, UART_IER);
+	fcr = serial8250_em_serial_in(p, UART_FCR_EM);
+	lcr = serial8250_em_serial_in(p, UART_LCR);
+	mcr = serial8250_em_serial_in(p, UART_MCR);
+	hcr0 = serial8250_em_serial_in(p, UART_HCR0_EM);
+
+	serial8250_em_serial_out_helper(p, UART_FCR_EM, fcr |
+							UART_FCR_CLEAR_RCVR |
+							UART_FCR_CLEAR_XMIT);
+	serial8250_em_serial_out_helper(p, UART_HCR0_EM, hcr0 |
+							 UART_HCR0_EM_SW_RESET);
+	serial8250_em_serial_out_helper(p, UART_HCR0_EM, hcr0 &
+							 ~UART_HCR0_EM_SW_RESET);
+
+	switch (off) {
+	case UART_FCR_EM:
+		fcr = value;
+		break;
+	case UART_LCR:
+		lcr = value;
+		break;
+	case UART_MCR:
+		mcr = value;
+		break;
+	}
+
+	serial8250_em_serial_out_helper(p, UART_IER, ier);
+	serial8250_em_serial_out_helper(p, UART_FCR_EM, fcr);
+	serial8250_em_serial_out_helper(p, UART_MCR, mcr);
+	serial8250_em_serial_out_helper(p, UART_LCR, lcr);
+	serial8250_em_serial_out_helper(p, UART_HCR0_EM, hcr0);
+}
+
+static void serial8250_em_serial_out(struct uart_port *p, int offset, int value)
+{
+	switch (offset) {
+	case UART_TX:
+	case UART_SCR:
+	case UART_IER:
+	case UART_DLL_EM:
+	case UART_DLM_EM:
+		serial8250_em_serial_out_helper(p, offset, value);
+		break;
+	case UART_FCR:
+		serial8250_em_reg_update(p, UART_FCR_EM, value);
+		break;
+	case UART_LCR:
+	case UART_MCR:
+		serial8250_em_reg_update(p, offset, value);
+		break;
+	}
+}
+
+static u32 serial8250_em_serial_dl_read(struct uart_8250_port *up)
+{
+	return serial_in(up, UART_DLL_EM) | serial_in(up, UART_DLM_EM) << 8;
+}
+
+static void serial8250_em_serial_dl_write(struct uart_8250_port *up, u32 value)
+{
+	serial_out(up, UART_DLL_EM, value & 0xff);
+	serial_out(up, UART_DLM_EM, value >> 8 & 0xff);
+}
+
+static int serial8250_em_probe(struct platform_device *pdev)
+{
+	struct serial8250_em_priv *priv;
+	struct device *dev = &pdev->dev;
+	struct uart_8250_port up;
+	struct resource *regs;
+	struct clk *sclk;
+	int irq, ret;
+
+	irq = platform_get_irq(pdev, 0);
+	if (irq < 0)
+		return irq;
+
+	regs = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (!regs)
+		return dev_err_probe(dev, -EINVAL, "missing registers\n");
+
+	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
+	if (!priv)
+		return -ENOMEM;
+
+	sclk = devm_clk_get_enabled(dev, "sclk");
+	if (IS_ERR(sclk))
+		return dev_err_probe(dev, PTR_ERR(sclk), "unable to get clock\n");
+
+	memset(&up, 0, sizeof(up));
+	up.port.mapbase = regs->start;
+	up.port.irq = irq;
+	up.port.type = PORT_16750;
+	up.port.flags = UPF_FIXED_PORT | UPF_IOREMAP | UPF_FIXED_TYPE;
+	up.port.dev = dev;
+	up.port.private_data = priv;
+
+	up.port.uartclk = clk_get_rate(sclk);
+
+	up.port.iotype = UPIO_MEM32;
+	up.port.serial_in = serial8250_em_serial_in;
+	up.port.serial_out = serial8250_em_serial_out;
+	up.dl_read = serial8250_em_serial_dl_read;
+	up.dl_write = serial8250_em_serial_dl_write;
+
+	ret = serial8250_register_8250_port(&up);
+	if (ret < 0)
+		return dev_err_probe(dev, ret, "unable to register 8250 port\n");
+
+	priv->line = ret;
+	platform_set_drvdata(pdev, priv);
+	return 0;
+}
+
+static int serial8250_em_remove(struct platform_device *pdev)
+{
+	struct serial8250_em_priv *priv = platform_get_drvdata(pdev);
+
+	serial8250_unregister_port(priv->line);
+	return 0;
+}
+
+static const struct of_device_id serial8250_em_dt_ids[] = {
+	{ .compatible = "renesas,em-uart", },
+	{},
+};
+MODULE_DEVICE_TABLE(of, serial8250_em_dt_ids);
+
+static struct platform_driver serial8250_em_platform_driver = {
+	.driver = {
+		.name		= "serial8250-em",
+		.of_match_table = serial8250_em_dt_ids,
+	},
+	.probe			= serial8250_em_probe,
+	.remove			= serial8250_em_remove,
+};
+
+module_platform_driver(serial8250_em_platform_driver);
+
+MODULE_AUTHOR("Magnus Damm");
+MODULE_DESCRIPTION("Renesas Emma Mobile 8250 Driver");
+MODULE_LICENSE("GPL v2");