1 files changed, 220 insertions, 37 deletions

diff --git a/drivers/tty/serial/8250/8250_dw.c b/drivers/tty/serial/8250/8250_dw.c
index 096d2ef48b3..db0e66f6dd0 100644
--- a/drivers/tty/serial/8250/8250_dw.c
+++ b/drivers/tty/serial/8250/8250_dw.c
@@ -2,6 +2,7 @@
  * Synopsys DesignWare 8250 driver.
  *
  * Copyright 2011 Picochip, Jamie Iles.
+ * Copyright 2013 Intel Corporation
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -24,6 +25,34 @@
 #include <linux/of_platform.h>
 #include <linux/platform_device.h>
 #include <linux/slab.h>
+#include <linux/acpi.h>
+
+#include "8250.h"
+
+/* Offsets for the DesignWare specific registers */
+#define DW_UART_USR	0x1f /* UART Status Register */
+#define DW_UART_CPR	0xf4 /* Component Parameter Register */
+#define DW_UART_UCV	0xf8 /* UART Component Version */
+
+/* Intel Low Power Subsystem specific */
+#define LPSS_PRV_CLOCK_PARAMS 0x800
+
+/* Component Parameter Register bits */
+#define DW_UART_CPR_ABP_DATA_WIDTH	(3 << 0)
+#define DW_UART_CPR_AFCE_MODE		(1 << 4)
+#define DW_UART_CPR_THRE_MODE		(1 << 5)
+#define DW_UART_CPR_SIR_MODE		(1 << 6)
+#define DW_UART_CPR_SIR_LP_MODE		(1 << 7)
+#define DW_UART_CPR_ADDITIONAL_FEATURES	(1 << 8)
+#define DW_UART_CPR_FIFO_ACCESS		(1 << 9)
+#define DW_UART_CPR_FIFO_STAT		(1 << 10)
+#define DW_UART_CPR_SHADOW		(1 << 11)
+#define DW_UART_CPR_ENCODED_PARMS	(1 << 12)
+#define DW_UART_CPR_DMA_EXTRA		(1 << 13)
+#define DW_UART_CPR_FIFO_MODE		(0xff << 16)
+/* Helper for fifo size calculation */
+#define DW_UART_CPR_FIFO_SIZE(a)	(((a >> 16) & 0xff) * 16)
+
 
 struct dw8250_data {
 	int	last_lcr;
@@ -66,9 +95,6 @@ static unsigned int dw8250_serial_in32(struct uart_port *p, int offset)
 	return readl(p->membase + offset);
 }
 
-/* Offset for the DesignWare's UART Status Register. */
-#define UART_USR	0x1f
-
 static int dw8250_handle_irq(struct uart_port *p)
 {
 	struct dw8250_data *d = p->private_data;
@@ -78,7 +104,7 @@ static int dw8250_handle_irq(struct uart_port *p)
 		return 1;
 	} else if ((iir & UART_IIR_BUSY) == UART_IIR_BUSY) {
 		/* Clear the USR and write the LCR again. */
-		(void)p->serial_in(p, UART_USR);
+		(void)p->serial_in(p, DW_UART_USR);
 		p->serial_out(p, UART_LCR, d->last_lcr);
 
 		return 1;
@@ -87,61 +113,210 @@ static int dw8250_handle_irq(struct uart_port *p)
 	return 0;
 }
 
+static int dw8250_probe_of(struct uart_port *p)
+{
+	struct device_node	*np = p->dev->of_node;
+	u32			val;
+
+	if (!of_property_read_u32(np, "reg-io-width", &val)) {
+		switch (val) {
+		case 1:
+			break;
+		case 4:
+			p->iotype = UPIO_MEM32;
+			p->serial_in = dw8250_serial_in32;
+			p->serial_out = dw8250_serial_out32;
+			break;
+		default:
+			dev_err(p->dev, "unsupported reg-io-width (%u)\n", val);
+			return -EINVAL;
+		}
+	}
+
+	if (!of_property_read_u32(np, "reg-shift", &val))
+		p->regshift = val;
+
+	if (of_property_read_u32(np, "clock-frequency", &val)) {
+		dev_err(p->dev, "no clock-frequency property set\n");
+		return -EINVAL;
+	}
+	p->uartclk = val;
+
+	return 0;
+}
+
+#ifdef CONFIG_ACPI
+static bool dw8250_acpi_dma_filter(struct dma_chan *chan, void *parm)
+{
+	return chan->chan_id == *(int *)parm;
+}
+
+static acpi_status
+dw8250_acpi_walk_resource(struct acpi_resource *res, void *data)
+{
+	struct uart_port		*p = data;
+	struct uart_8250_port		*port;
+	struct uart_8250_dma		*dma;
+	struct acpi_resource_fixed_dma	*fixed_dma;
+	struct dma_slave_config		*slave;
+
+	port = container_of(p, struct uart_8250_port, port);
+
+	switch (res->type) {
+	case ACPI_RESOURCE_TYPE_FIXED_DMA:
+		fixed_dma = &res->data.fixed_dma;
+
+		/* TX comes first */
+		if (!port->dma) {
+			dma = devm_kzalloc(p->dev, sizeof(*dma), GFP_KERNEL);
+			if (!dma)
+				return AE_NO_MEMORY;
+
+			port->dma = dma;
+			slave = &dma->txconf;
+
+			slave->direction	= DMA_MEM_TO_DEV;
+			slave->dst_addr_width	= DMA_SLAVE_BUSWIDTH_1_BYTE;
+			slave->slave_id		= fixed_dma->request_lines;
+			slave->dst_maxburst	= port->tx_loadsz / 4;
+
+			dma->tx_chan_id		= fixed_dma->channels;
+			dma->tx_param		= &dma->tx_chan_id;
+			dma->fn			= dw8250_acpi_dma_filter;
+		} else {
+			dma = port->dma;
+			slave = &dma->rxconf;
+
+			slave->direction	= DMA_DEV_TO_MEM;
+			slave->src_addr_width	= DMA_SLAVE_BUSWIDTH_1_BYTE;
+			slave->slave_id		= fixed_dma->request_lines;
+			slave->src_maxburst	= p->fifosize / 4;
+
+			dma->rx_chan_id		= fixed_dma->channels;
+			dma->rx_param		= &dma->rx_chan_id;
+		}
+
+		break;
+	}
+
+	return AE_OK;
+}
+
+static int dw8250_probe_acpi(struct uart_port *p)
+{
+	const struct acpi_device_id *id;
+	acpi_status status;
+	u32 reg;
+
+	id = acpi_match_device(p->dev->driver->acpi_match_table, p->dev);
+	if (!id)
+		return -ENODEV;
+
+	p->iotype = UPIO_MEM32;
+	p->serial_in = dw8250_serial_in32;
+	p->serial_out = dw8250_serial_out32;
+	p->regshift = 2;
+	p->uartclk = (unsigned int)id->driver_data;
+
+	status = acpi_walk_resources(ACPI_HANDLE(p->dev), METHOD_NAME__CRS,
+				     dw8250_acpi_walk_resource, p);
+	if (ACPI_FAILURE(status)) {
+		dev_err_ratelimited(p->dev, "%s failed \"%s\"\n", __func__,
+				    acpi_format_exception(status));
+		return -ENODEV;
+	}
+
+	/* Fix Haswell issue where the clocks do not get enabled */
+	if (!strcmp(id->id, "INT33C4") || !strcmp(id->id, "INT33C5")) {
+		reg = readl(p->membase + LPSS_PRV_CLOCK_PARAMS);
+		writel(reg | 1, p->membase + LPSS_PRV_CLOCK_PARAMS);
+	}
+
+	return 0;
+}
+#else
+static inline int dw8250_probe_acpi(struct uart_port *p)
+{
+	return -ENODEV;
+}
+#endif /* CONFIG_ACPI */
+
+static void dw8250_setup_port(struct uart_8250_port *up)
+{
+	struct uart_port	*p = &up->port;
+	u32			reg = readl(p->membase + DW_UART_UCV);
+
+	/*
+	 * If the Component Version Register returns zero, we know that
+	 * ADDITIONAL_FEATURES are not enabled. No need to go any further.
+	 */
+	if (!reg)
+		return;
+
+	dev_dbg_ratelimited(p->dev, "Designware UART version %c.%c%c\n",
+		(reg >> 24) & 0xff, (reg >> 16) & 0xff, (reg >> 8) & 0xff);
+
+	reg = readl(p->membase + DW_UART_CPR);
+	if (!reg)
+		return;
+
+	/* Select the type based on fifo */
+	if (reg & DW_UART_CPR_FIFO_MODE) {
+		p->type = PORT_16550A;
+		p->flags |= UPF_FIXED_TYPE;
+		p->fifosize = DW_UART_CPR_FIFO_SIZE(reg);
+		up->tx_loadsz = p->fifosize;
+	}
+}
+
 static int dw8250_probe(struct platform_device *pdev)
 {
 	struct uart_8250_port uart = {};
 	struct resource *regs = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 	struct resource *irq = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
-	struct device_node *np = pdev->dev.of_node;
-	u32 val;
 	struct dw8250_data *data;
+	int err;
 
 	if (!regs || !irq) {
 		dev_err(&pdev->dev, "no registers/irq defined\n");
 		return -EINVAL;
 	}
 
-	data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL);
-	if (!data)
-		return -ENOMEM;
-	uart.port.private_data = data;
-
 	spin_lock_init(&uart.port.lock);
 	uart.port.mapbase = regs->start;
 	uart.port.irq = irq->start;
 	uart.port.handle_irq = dw8250_handle_irq;
 	uart.port.type = PORT_8250;
-	uart.port.flags = UPF_SHARE_IRQ | UPF_BOOT_AUTOCONF | UPF_IOREMAP |
-		UPF_FIXED_PORT | UPF_FIXED_TYPE;
+	uart.port.flags = UPF_SHARE_IRQ | UPF_BOOT_AUTOCONF | UPF_FIXED_PORT;
 	uart.port.dev = &pdev->dev;
 
+	uart.port.membase = ioremap(regs->start, resource_size(regs));
+	if (!uart.port.membase)
+		return -ENOMEM;
+
 	uart.port.iotype = UPIO_MEM;
 	uart.port.serial_in = dw8250_serial_in;
 	uart.port.serial_out = dw8250_serial_out;
-	if (!of_property_read_u32(np, "reg-io-width", &val)) {
-		switch (val) {
-		case 1:
-			break;
-		case 4:
-			uart.port.iotype = UPIO_MEM32;
-			uart.port.serial_in = dw8250_serial_in32;
-			uart.port.serial_out = dw8250_serial_out32;
-			break;
-		default:
-			dev_err(&pdev->dev, "unsupported reg-io-width (%u)\n",
-				val);
-			return -EINVAL;
-		}
+
+	dw8250_setup_port(&uart);
+
+	if (pdev->dev.of_node) {
+		err = dw8250_probe_of(&uart.port);
+		if (err)
+			return err;
+	} else if (ACPI_HANDLE(&pdev->dev)) {
+		err = dw8250_probe_acpi(&uart.port);
+		if (err)
+			return err;
+	} else {
+		return -ENODEV;
 	}
 
-	if (!of_property_read_u32(np, "reg-shift", &val))
-		uart.port.regshift = val;
+	data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL);
+	if (!data)
+		return -ENOMEM;
 
-	if (of_property_read_u32(np, "clock-frequency", &val)) {
-		dev_err(&pdev->dev, "no clock-frequency property set\n");
-		return -EINVAL;
-	}
-	uart.port.uartclk = val;
+	uart.port.private_data = data;
 
 	data->line = serial8250_register_8250_port(&uart);
 	if (data->line < 0)
@@ -184,17 +359,25 @@ static int dw8250_resume(struct platform_device *pdev)
 #define dw8250_resume NULL
 #endif /* CONFIG_PM */
 
-static const struct of_device_id dw8250_match[] = {
+static const struct of_device_id dw8250_of_match[] = {
 	{ .compatible = "snps,dw-apb-uart" },
 	{ /* Sentinel */ }
 };
-MODULE_DEVICE_TABLE(of, dw8250_match);
+MODULE_DEVICE_TABLE(of, dw8250_of_match);
+
+static const struct acpi_device_id dw8250_acpi_match[] = {
+	{ "INT33C4", 100000000 },
+	{ "INT33C5", 100000000 },
+	{ },
+};
+MODULE_DEVICE_TABLE(acpi, dw8250_acpi_match);
 
 static struct platform_driver dw8250_platform_driver = {
 	.driver = {
 		.name		= "dw-apb-uart",
 		.owner		= THIS_MODULE,
-		.of_match_table	= dw8250_match,
+		.of_match_table	= dw8250_of_match,
+		.acpi_match_table = ACPI_PTR(dw8250_acpi_match),
 	},
 	.probe			= dw8250_probe,
 	.remove			= dw8250_remove,