1 files changed, 455 insertions, 0 deletions

diff --git a/drivers/usb/musb/musbhsdma.c b/drivers/usb/musb/musbhsdma.c
new file mode 100644
index 000000000..7acd16358
--- /dev/null
+++ b/drivers/usb/musb/musbhsdma.c
@@ -0,0 +1,455 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * MUSB OTG driver - support for Mentor's DMA controller
+ *
+ * Copyright 2005 Mentor Graphics Corporation
+ * Copyright (C) 2005-2007 by Texas Instruments
+ */
+#include <linux/device.h>
+#include <linux/interrupt.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include "musb_core.h"
+#include "musb_dma.h"
+
+#define MUSB_HSDMA_CHANNEL_OFFSET(_bchannel, _offset)		\
+		(MUSB_HSDMA_BASE + (_bchannel << 4) + _offset)
+
+#define musb_read_hsdma_addr(mbase, bchannel)	\
+	musb_readl(mbase,	\
+		   MUSB_HSDMA_CHANNEL_OFFSET(bchannel, MUSB_HSDMA_ADDRESS))
+
+#define musb_write_hsdma_addr(mbase, bchannel, addr) \
+	musb_writel(mbase, \
+		    MUSB_HSDMA_CHANNEL_OFFSET(bchannel, MUSB_HSDMA_ADDRESS), \
+		    addr)
+
+#define musb_read_hsdma_count(mbase, bchannel)	\
+	musb_readl(mbase,	\
+		   MUSB_HSDMA_CHANNEL_OFFSET(bchannel, MUSB_HSDMA_COUNT))
+
+#define musb_write_hsdma_count(mbase, bchannel, len) \
+	musb_writel(mbase, \
+		    MUSB_HSDMA_CHANNEL_OFFSET(bchannel, MUSB_HSDMA_COUNT), \
+		    len)
+/* control register (16-bit): */
+#define MUSB_HSDMA_ENABLE_SHIFT		0
+#define MUSB_HSDMA_TRANSMIT_SHIFT	1
+#define MUSB_HSDMA_MODE1_SHIFT		2
+#define MUSB_HSDMA_IRQENABLE_SHIFT	3
+#define MUSB_HSDMA_ENDPOINT_SHIFT	4
+#define MUSB_HSDMA_BUSERROR_SHIFT	8
+#define MUSB_HSDMA_BURSTMODE_SHIFT	9
+#define MUSB_HSDMA_BURSTMODE		(3 << MUSB_HSDMA_BURSTMODE_SHIFT)
+#define MUSB_HSDMA_BURSTMODE_UNSPEC	0
+#define MUSB_HSDMA_BURSTMODE_INCR4	1
+#define MUSB_HSDMA_BURSTMODE_INCR8	2
+#define MUSB_HSDMA_BURSTMODE_INCR16	3
+
+#define MUSB_HSDMA_CHANNELS		8
+
+struct musb_dma_controller;
+
+struct musb_dma_channel {
+	struct dma_channel		channel;
+	struct musb_dma_controller	*controller;
+	u32				start_addr;
+	u32				len;
+	u16				max_packet_sz;
+	u8				idx;
+	u8				epnum;
+	u8				transmit;
+};
+
+struct musb_dma_controller {
+	struct dma_controller		controller;
+	struct musb_dma_channel		channel[MUSB_HSDMA_CHANNELS];
+	void				*private_data;
+	void __iomem			*base;
+	u8				channel_count;
+	u8				used_channels;
+	int				irq;
+};
+
+static void dma_channel_release(struct dma_channel *channel);
+
+static void dma_controller_stop(struct musb_dma_controller *controller)
+{
+	struct musb *musb = controller->private_data;
+	struct dma_channel *channel;
+	u8 bit;
+
+	if (controller->used_channels != 0) {
+		dev_err(musb->controller,
+			"Stopping DMA controller while channel active\n");
+
+		for (bit = 0; bit < MUSB_HSDMA_CHANNELS; bit++) {
+			if (controller->used_channels & (1 << bit)) {
+				channel = &controller->channel[bit].channel;
+				dma_channel_release(channel);
+
+				if (!controller->used_channels)
+					break;
+			}
+		}
+	}
+}
+
+static struct dma_channel *dma_channel_allocate(struct dma_controller *c,
+				struct musb_hw_ep *hw_ep, u8 transmit)
+{
+	struct musb_dma_controller *controller = container_of(c,
+			struct musb_dma_controller, controller);
+	struct musb_dma_channel *musb_channel = NULL;
+	struct dma_channel *channel = NULL;
+	u8 bit;
+
+	for (bit = 0; bit < MUSB_HSDMA_CHANNELS; bit++) {
+		if (!(controller->used_channels & (1 << bit))) {
+			controller->used_channels |= (1 << bit);
+			musb_channel = &(controller->channel[bit]);
+			musb_channel->controller = controller;
+			musb_channel->idx = bit;
+			musb_channel->epnum = hw_ep->epnum;
+			musb_channel->transmit = transmit;
+			channel = &(musb_channel->channel);
+			channel->private_data = musb_channel;
+			channel->status = MUSB_DMA_STATUS_FREE;
+			channel->max_len = 0x100000;
+			/* Tx => mode 1; Rx => mode 0 */
+			channel->desired_mode = transmit;
+			channel->actual_len = 0;
+			break;
+		}
+	}
+
+	return channel;
+}
+
+static void dma_channel_release(struct dma_channel *channel)
+{
+	struct musb_dma_channel *musb_channel = channel->private_data;
+
+	channel->actual_len = 0;
+	musb_channel->start_addr = 0;
+	musb_channel->len = 0;
+
+	musb_channel->controller->used_channels &=
+		~(1 << musb_channel->idx);
+
+	channel->status = MUSB_DMA_STATUS_UNKNOWN;
+}
+
+static void configure_channel(struct dma_channel *channel,
+				u16 packet_sz, u8 mode,
+				dma_addr_t dma_addr, u32 len)
+{
+	struct musb_dma_channel *musb_channel = channel->private_data;
+	struct musb_dma_controller *controller = musb_channel->controller;
+	struct musb *musb = controller->private_data;
+	void __iomem *mbase = controller->base;
+	u8 bchannel = musb_channel->idx;
+	u16 csr = 0;
+
+	musb_dbg(musb, "%p, pkt_sz %d, addr %pad, len %d, mode %d",
+			channel, packet_sz, &dma_addr, len, mode);
+
+	if (mode) {
+		csr |= 1 << MUSB_HSDMA_MODE1_SHIFT;
+		BUG_ON(len < packet_sz);
+	}
+	csr |= MUSB_HSDMA_BURSTMODE_INCR16
+				<< MUSB_HSDMA_BURSTMODE_SHIFT;
+
+	csr |= (musb_channel->epnum << MUSB_HSDMA_ENDPOINT_SHIFT)
+		| (1 << MUSB_HSDMA_ENABLE_SHIFT)
+		| (1 << MUSB_HSDMA_IRQENABLE_SHIFT)
+		| (musb_channel->transmit
+				? (1 << MUSB_HSDMA_TRANSMIT_SHIFT)
+				: 0);
+
+	/* address/count */
+	musb_write_hsdma_addr(mbase, bchannel, dma_addr);
+	musb_write_hsdma_count(mbase, bchannel, len);
+
+	/* control (this should start things) */
+	musb_writew(mbase,
+		MUSB_HSDMA_CHANNEL_OFFSET(bchannel, MUSB_HSDMA_CONTROL),
+		csr);
+}
+
+static int dma_channel_program(struct dma_channel *channel,
+				u16 packet_sz, u8 mode,
+				dma_addr_t dma_addr, u32 len)
+{
+	struct musb_dma_channel *musb_channel = channel->private_data;
+	struct musb_dma_controller *controller = musb_channel->controller;
+	struct musb *musb = controller->private_data;
+
+	musb_dbg(musb, "ep%d-%s pkt_sz %d, dma_addr %pad length %d, mode %d",
+		musb_channel->epnum,
+		musb_channel->transmit ? "Tx" : "Rx",
+		packet_sz, &dma_addr, len, mode);
+
+	BUG_ON(channel->status == MUSB_DMA_STATUS_UNKNOWN ||
+		channel->status == MUSB_DMA_STATUS_BUSY);
+
+	/*
+	 * The DMA engine in RTL1.8 and above cannot handle
+	 * DMA addresses that are not aligned to a 4 byte boundary.
+	 * It ends up masking the last two bits of the address
+	 * programmed in DMA_ADDR.
+	 *
+	 * Fail such DMA transfers, so that the backup PIO mode
+	 * can carry out the transfer
+	 */
+	if ((musb->hwvers >= MUSB_HWVERS_1800) && (dma_addr % 4))
+		return false;
+
+	channel->actual_len = 0;
+	musb_channel->start_addr = dma_addr;
+	musb_channel->len = len;
+	musb_channel->max_packet_sz = packet_sz;
+	channel->status = MUSB_DMA_STATUS_BUSY;
+
+	configure_channel(channel, packet_sz, mode, dma_addr, len);
+
+	return true;
+}
+
+static int dma_channel_abort(struct dma_channel *channel)
+{
+	struct musb_dma_channel *musb_channel = channel->private_data;
+	void __iomem *mbase = musb_channel->controller->base;
+	struct musb *musb = musb_channel->controller->private_data;
+
+	u8 bchannel = musb_channel->idx;
+	int offset;
+	u16 csr;
+
+	if (channel->status == MUSB_DMA_STATUS_BUSY) {
+		if (musb_channel->transmit) {
+			offset = musb->io.ep_offset(musb_channel->epnum,
+						MUSB_TXCSR);
+
+			/*
+			 * The programming guide says that we must clear
+			 * the DMAENAB bit before the DMAMODE bit...
+			 */
+			csr = musb_readw(mbase, offset);
+			csr &= ~(MUSB_TXCSR_AUTOSET | MUSB_TXCSR_DMAENAB);
+			musb_writew(mbase, offset, csr);
+			csr &= ~MUSB_TXCSR_DMAMODE;
+			musb_writew(mbase, offset, csr);
+		} else {
+			offset = musb->io.ep_offset(musb_channel->epnum,
+						MUSB_RXCSR);
+
+			csr = musb_readw(mbase, offset);
+			csr &= ~(MUSB_RXCSR_AUTOCLEAR |
+				 MUSB_RXCSR_DMAENAB |
+				 MUSB_RXCSR_DMAMODE);
+			musb_writew(mbase, offset, csr);
+		}
+
+		musb_writew(mbase,
+			MUSB_HSDMA_CHANNEL_OFFSET(bchannel, MUSB_HSDMA_CONTROL),
+			0);
+		musb_write_hsdma_addr(mbase, bchannel, 0);
+		musb_write_hsdma_count(mbase, bchannel, 0);
+		channel->status = MUSB_DMA_STATUS_FREE;
+	}
+
+	return 0;
+}
+
+irqreturn_t dma_controller_irq(int irq, void *private_data)
+{
+	struct musb_dma_controller *controller = private_data;
+	struct musb *musb = controller->private_data;
+	struct musb_dma_channel *musb_channel;
+	struct dma_channel *channel;
+
+	void __iomem *mbase = controller->base;
+
+	irqreturn_t retval = IRQ_NONE;
+
+	unsigned long flags;
+
+	u8 bchannel;
+	u8 int_hsdma;
+
+	u32 addr, count;
+	u16 csr;
+
+	spin_lock_irqsave(&musb->lock, flags);
+
+	int_hsdma = musb_clearb(mbase, MUSB_HSDMA_INTR);
+
+	if (!int_hsdma) {
+		musb_dbg(musb, "spurious DMA irq");
+
+		for (bchannel = 0; bchannel < MUSB_HSDMA_CHANNELS; bchannel++) {
+			musb_channel = (struct musb_dma_channel *)
+					&(controller->channel[bchannel]);
+			channel = &musb_channel->channel;
+			if (channel->status == MUSB_DMA_STATUS_BUSY) {
+				count = musb_read_hsdma_count(mbase, bchannel);
+
+				if (count == 0)
+					int_hsdma |= (1 << bchannel);
+			}
+		}
+
+		musb_dbg(musb, "int_hsdma = 0x%x", int_hsdma);
+
+		if (!int_hsdma)
+			goto done;
+	}
+
+	for (bchannel = 0; bchannel < MUSB_HSDMA_CHANNELS; bchannel++) {
+		if (int_hsdma & (1 << bchannel)) {
+			musb_channel = (struct musb_dma_channel *)
+					&(controller->channel[bchannel]);
+			channel = &musb_channel->channel;
+
+			csr = musb_readw(mbase,
+					MUSB_HSDMA_CHANNEL_OFFSET(bchannel,
+							MUSB_HSDMA_CONTROL));
+
+			if (csr & (1 << MUSB_HSDMA_BUSERROR_SHIFT)) {
+				musb_channel->channel.status =
+					MUSB_DMA_STATUS_BUS_ABORT;
+			} else {
+				addr = musb_read_hsdma_addr(mbase,
+						bchannel);
+				channel->actual_len = addr
+					- musb_channel->start_addr;
+
+				musb_dbg(musb, "ch %p, 0x%x -> 0x%x (%zu / %d) %s",
+					channel, musb_channel->start_addr,
+					addr, channel->actual_len,
+					musb_channel->len,
+					(channel->actual_len
+						< musb_channel->len) ?
+					"=> reconfig 0" : "=> complete");
+
+				channel->status = MUSB_DMA_STATUS_FREE;
+
+				/* completed */
+				if (musb_channel->transmit &&
+					(!channel->desired_mode ||
+					(channel->actual_len %
+					    musb_channel->max_packet_sz))) {
+					u8  epnum  = musb_channel->epnum;
+					int offset = musb->io.ep_offset(epnum,
+								    MUSB_TXCSR);
+					u16 txcsr;
+
+					/*
+					 * The programming guide says that we
+					 * must clear DMAENAB before DMAMODE.
+					 */
+					musb_ep_select(mbase, epnum);
+					txcsr = musb_readw(mbase, offset);
+					if (channel->desired_mode == 1) {
+						txcsr &= ~(MUSB_TXCSR_DMAENAB
+							| MUSB_TXCSR_AUTOSET);
+						musb_writew(mbase, offset, txcsr);
+						/* Send out the packet */
+						txcsr &= ~MUSB_TXCSR_DMAMODE;
+						txcsr |= MUSB_TXCSR_DMAENAB;
+					}
+					txcsr |=  MUSB_TXCSR_TXPKTRDY;
+					musb_writew(mbase, offset, txcsr);
+				}
+				musb_dma_completion(musb, musb_channel->epnum,
+						    musb_channel->transmit);
+			}
+		}
+	}
+
+	retval = IRQ_HANDLED;
+done:
+	spin_unlock_irqrestore(&musb->lock, flags);
+	return retval;
+}
+EXPORT_SYMBOL_GPL(dma_controller_irq);
+
+void musbhs_dma_controller_destroy(struct dma_controller *c)
+{
+	struct musb_dma_controller *controller = container_of(c,
+			struct musb_dma_controller, controller);
+
+	dma_controller_stop(controller);
+
+	if (controller->irq)
+		free_irq(controller->irq, c);
+
+	kfree(controller);
+}
+EXPORT_SYMBOL_GPL(musbhs_dma_controller_destroy);
+
+static struct musb_dma_controller *
+dma_controller_alloc(struct musb *musb, void __iomem *base)
+{
+	struct musb_dma_controller *controller;
+
+	controller = kzalloc(sizeof(*controller), GFP_KERNEL);
+	if (!controller)
+		return NULL;
+
+	controller->channel_count = MUSB_HSDMA_CHANNELS;
+	controller->private_data = musb;
+	controller->base = base;
+
+	controller->controller.channel_alloc = dma_channel_allocate;
+	controller->controller.channel_release = dma_channel_release;
+	controller->controller.channel_program = dma_channel_program;
+	controller->controller.channel_abort = dma_channel_abort;
+	return controller;
+}
+
+struct dma_controller *
+musbhs_dma_controller_create(struct musb *musb, void __iomem *base)
+{
+	struct musb_dma_controller *controller;
+	struct device *dev = musb->controller;
+	struct platform_device *pdev = to_platform_device(dev);
+	int irq = platform_get_irq_byname(pdev, "dma");
+
+	if (irq <= 0) {
+		dev_err(dev, "No DMA interrupt line!\n");
+		return NULL;
+	}
+
+	controller = dma_controller_alloc(musb, base);
+	if (!controller)
+		return NULL;
+
+	if (request_irq(irq, dma_controller_irq, 0,
+			dev_name(musb->controller), controller)) {
+		dev_err(dev, "request_irq %d failed!\n", irq);
+		musb_dma_controller_destroy(&controller->controller);
+
+		return NULL;
+	}
+
+	controller->irq = irq;
+
+	return &controller->controller;
+}
+EXPORT_SYMBOL_GPL(musbhs_dma_controller_create);
+
+struct dma_controller *
+musbhs_dma_controller_create_noirq(struct musb *musb, void __iomem *base)
+{
+	struct musb_dma_controller *controller;
+
+	controller = dma_controller_alloc(musb, base);
+	if (!controller)
+		return NULL;
+
+	return &controller->controller;
+}
+EXPORT_SYMBOL_GPL(musbhs_dma_controller_create_noirq);