[05/14] usb: musb: remove unused davinci support

Message ID 20221019152947.3857217-6-arnd@kernel.org
State New
Headers
Series ARM: remove unused davinci board & drivers |

Commit Message

Arnd Bergmann Oct. 19, 2022, 3:29 p.m. UTC
  From: Arnd Bergmann <arnd@arndb.de>

The musb-davinci driver was only used on dm644x, which got removed
in linux-6.0. The only remaining davinci machines are da8xx
devicetree based and do not use this hardware.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
---
 drivers/usb/musb/Kconfig    |   12 -
 drivers/usb/musb/Makefile   |    2 -
 drivers/usb/musb/cppi_dma.c | 1547 -----------------------------------
 drivers/usb/musb/davinci.c  |  606 --------------
 drivers/usb/musb/davinci.h  |  103 ---
 5 files changed, 2270 deletions(-)
 delete mode 100644 drivers/usb/musb/cppi_dma.c
 delete mode 100644 drivers/usb/musb/davinci.c
 delete mode 100644 drivers/usb/musb/davinci.h
  

Comments

Bartosz Golaszewski Oct. 20, 2022, 11:34 a.m. UTC | #1
On Wed, Oct 19, 2022 at 5:34 PM Arnd Bergmann <arnd@kernel.org> wrote:
>
> From: Arnd Bergmann <arnd@arndb.de>
>
> The musb-davinci driver was only used on dm644x, which got removed
> in linux-6.0. The only remaining davinci machines are da8xx
> devicetree based and do not use this hardware.
>
> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
> ---

Acked-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
  

Patch

diff --git a/drivers/usb/musb/Kconfig b/drivers/usb/musb/Kconfig
index 6c8f7763e75e..f9eec666103c 100644
--- a/drivers/usb/musb/Kconfig
+++ b/drivers/usb/musb/Kconfig
@@ -70,12 +70,6 @@  config USB_MUSB_SUNXI
 	select GENERIC_PHY
 	select SUNXI_SRAM
 
-config USB_MUSB_DAVINCI
-	tristate "DaVinci"
-	depends on ARCH_DAVINCI_DMx
-	depends on NOP_USB_XCEIV
-	depends on BROKEN
-
 config USB_MUSB_DA8XX
 	tristate "DA8xx/OMAP-L1x"
 	depends on ARCH_DAVINCI_DA8XX
@@ -161,12 +155,6 @@  config USB_INVENTRA_DMA
 	help
 	  Enable DMA transfers using Mentor's engine.
 
-config USB_TI_CPPI_DMA
-	bool 'TI CPPI (Davinci)'
-	depends on USB_MUSB_DAVINCI
-	help
-	  Enable DMA transfers when TI CPPI DMA is available.
-
 config USB_TI_CPPI41_DMA
 	bool 'TI CPPI 4.1'
 	depends on (ARCH_OMAP || ARCH_DAVINCI_DA8XX) && DMADEVICES
diff --git a/drivers/usb/musb/Makefile b/drivers/usb/musb/Makefile
index 51dd54a8de49..44a9e27b2157 100644
--- a/drivers/usb/musb/Makefile
+++ b/drivers/usb/musb/Makefile
@@ -19,7 +19,6 @@  obj-$(CONFIG_USB_MUSB_OMAP2PLUS)		+= omap2430.o
 obj-$(CONFIG_USB_MUSB_AM35X)			+= am35x.o
 obj-$(CONFIG_USB_MUSB_DSPS)			+= musb_dsps.o
 obj-$(CONFIG_USB_MUSB_TUSB6010)			+= tusb6010.o
-obj-$(CONFIG_USB_MUSB_DAVINCI)			+= davinci.o
 obj-$(CONFIG_USB_MUSB_DA8XX)			+= da8xx.o
 obj-$(CONFIG_USB_MUSB_UX500)			+= ux500.o
 obj-$(CONFIG_USB_MUSB_JZ4740)			+= jz4740.o
@@ -33,7 +32,6 @@  obj-$(CONFIG_USB_MUSB_POLARFIRE_SOC)		+= mpfs.o
 # though PIO is always there to back up DMA, and for ep0
 
 musb_hdrc-$(CONFIG_USB_INVENTRA_DMA)		+= musbhsdma.o
-musb_hdrc-$(CONFIG_USB_TI_CPPI_DMA)		+= cppi_dma.o
 musb_hdrc-$(CONFIG_USB_TUSB_OMAP_DMA)		+= tusb6010_omap.o
 musb_hdrc-$(CONFIG_USB_UX500_DMA)		+= ux500_dma.o
 musb_hdrc-$(CONFIG_USB_TI_CPPI41_DMA)		+= musb_cppi41.o
diff --git a/drivers/usb/musb/cppi_dma.c b/drivers/usb/musb/cppi_dma.c
deleted file mode 100644
index edb5b63d7063..000000000000
--- a/drivers/usb/musb/cppi_dma.c
+++ /dev/null
@@ -1,1547 +0,0 @@ 
-// SPDX-License-Identifier: GPL-2.0
-/*
- * Copyright (C) 2005-2006 by Texas Instruments
- *
- * This file implements a DMA  interface using TI's CPPI DMA.
- * For now it's DaVinci-only, but CPPI isn't specific to DaVinci or USB.
- * The TUSB6020, using VLYNQ, has CPPI that looks much like DaVinci.
- */
-
-#include <linux/module.h>
-#include <linux/platform_device.h>
-#include <linux/slab.h>
-#include <linux/usb.h>
-
-#include "musb_core.h"
-#include "musb_debug.h"
-#include "cppi_dma.h"
-#include "davinci.h"
-
-
-/* CPPI DMA status 7-mar-2006:
- *
- * - See musb_{host,gadget}.c for more info
- *
- * - Correct RX DMA generally forces the engine into irq-per-packet mode,
- *   which can easily saturate the CPU under non-mass-storage loads.
- *
- * NOTES 24-aug-2006 (2.6.18-rc4):
- *
- * - peripheral RXDMA wedged in a test with packets of length 512/512/1.
- *   evidently after the 1 byte packet was received and acked, the queue
- *   of BDs got garbaged so it wouldn't empty the fifo.  (rxcsr 0x2003,
- *   and RX DMA0: 4 left, 80000000 8feff880, 8feff860 8feff860; 8f321401
- *   004001ff 00000001 .. 8feff860)  Host was just getting NAKed on tx
- *   of its next (512 byte) packet.  IRQ issues?
- *
- * REVISIT:  the "transfer DMA" glue between CPPI and USB fifos will
- * evidently also directly update the RX and TX CSRs ... so audit all
- * host and peripheral side DMA code to avoid CSR access after DMA has
- * been started.
- */
-
-/* REVISIT now we can avoid preallocating these descriptors; or
- * more simply, switch to a global freelist not per-channel ones.
- * Note: at full speed, 64 descriptors == 4K bulk data.
- */
-#define NUM_TXCHAN_BD       64
-#define NUM_RXCHAN_BD       64
-
-static inline void cpu_drain_writebuffer(void)
-{
-	wmb();
-#ifdef	CONFIG_CPU_ARM926T
-	/* REVISIT this "should not be needed",
-	 * but lack of it sure seemed to hurt ...
-	 */
-	asm("mcr p15, 0, r0, c7, c10, 4 @ drain write buffer\n");
-#endif
-}
-
-static inline struct cppi_descriptor *cppi_bd_alloc(struct cppi_channel *c)
-{
-	struct cppi_descriptor	*bd = c->freelist;
-
-	if (bd)
-		c->freelist = bd->next;
-	return bd;
-}
-
-static inline void
-cppi_bd_free(struct cppi_channel *c, struct cppi_descriptor *bd)
-{
-	if (!bd)
-		return;
-	bd->next = c->freelist;
-	c->freelist = bd;
-}
-
-/*
- *  Start DMA controller
- *
- *  Initialize the DMA controller as necessary.
- */
-
-/* zero out entire rx state RAM entry for the channel */
-static void cppi_reset_rx(struct cppi_rx_stateram __iomem *rx)
-{
-	musb_writel(&rx->rx_skipbytes, 0, 0);
-	musb_writel(&rx->rx_head, 0, 0);
-	musb_writel(&rx->rx_sop, 0, 0);
-	musb_writel(&rx->rx_current, 0, 0);
-	musb_writel(&rx->rx_buf_current, 0, 0);
-	musb_writel(&rx->rx_len_len, 0, 0);
-	musb_writel(&rx->rx_cnt_cnt, 0, 0);
-}
-
-/* zero out entire tx state RAM entry for the channel */
-static void cppi_reset_tx(struct cppi_tx_stateram __iomem *tx, u32 ptr)
-{
-	musb_writel(&tx->tx_head, 0, 0);
-	musb_writel(&tx->tx_buf, 0, 0);
-	musb_writel(&tx->tx_current, 0, 0);
-	musb_writel(&tx->tx_buf_current, 0, 0);
-	musb_writel(&tx->tx_info, 0, 0);
-	musb_writel(&tx->tx_rem_len, 0, 0);
-	/* musb_writel(&tx->tx_dummy, 0, 0); */
-	musb_writel(&tx->tx_complete, 0, ptr);
-}
-
-static void cppi_pool_init(struct cppi *cppi, struct cppi_channel *c)
-{
-	int	j;
-
-	/* initialize channel fields */
-	c->head = NULL;
-	c->tail = NULL;
-	c->last_processed = NULL;
-	c->channel.status = MUSB_DMA_STATUS_UNKNOWN;
-	c->controller = cppi;
-	c->is_rndis = 0;
-	c->freelist = NULL;
-
-	/* build the BD Free list for the channel */
-	for (j = 0; j < NUM_TXCHAN_BD + 1; j++) {
-		struct cppi_descriptor	*bd;
-		dma_addr_t		dma;
-
-		bd = dma_pool_alloc(cppi->pool, GFP_KERNEL, &dma);
-		bd->dma = dma;
-		cppi_bd_free(c, bd);
-	}
-}
-
-static int cppi_channel_abort(struct dma_channel *);
-
-static void cppi_pool_free(struct cppi_channel *c)
-{
-	struct cppi		*cppi = c->controller;
-	struct cppi_descriptor	*bd;
-
-	(void) cppi_channel_abort(&c->channel);
-	c->channel.status = MUSB_DMA_STATUS_UNKNOWN;
-	c->controller = NULL;
-
-	/* free all its bds */
-	bd = c->last_processed;
-	do {
-		if (bd)
-			dma_pool_free(cppi->pool, bd, bd->dma);
-		bd = cppi_bd_alloc(c);
-	} while (bd);
-	c->last_processed = NULL;
-}
-
-static void cppi_controller_start(struct cppi *controller)
-{
-	void __iomem	*tibase;
-	int		i;
-
-	/* do whatever is necessary to start controller */
-	for (i = 0; i < ARRAY_SIZE(controller->tx); i++) {
-		controller->tx[i].transmit = true;
-		controller->tx[i].index = i;
-	}
-	for (i = 0; i < ARRAY_SIZE(controller->rx); i++) {
-		controller->rx[i].transmit = false;
-		controller->rx[i].index = i;
-	}
-
-	/* setup BD list on a per channel basis */
-	for (i = 0; i < ARRAY_SIZE(controller->tx); i++)
-		cppi_pool_init(controller, controller->tx + i);
-	for (i = 0; i < ARRAY_SIZE(controller->rx); i++)
-		cppi_pool_init(controller, controller->rx + i);
-
-	tibase =  controller->tibase;
-	INIT_LIST_HEAD(&controller->tx_complete);
-
-	/* initialise tx/rx channel head pointers to zero */
-	for (i = 0; i < ARRAY_SIZE(controller->tx); i++) {
-		struct cppi_channel	*tx_ch = controller->tx + i;
-		struct cppi_tx_stateram __iomem *tx;
-
-		INIT_LIST_HEAD(&tx_ch->tx_complete);
-
-		tx = tibase + DAVINCI_TXCPPI_STATERAM_OFFSET(i);
-		tx_ch->state_ram = tx;
-		cppi_reset_tx(tx, 0);
-	}
-	for (i = 0; i < ARRAY_SIZE(controller->rx); i++) {
-		struct cppi_channel	*rx_ch = controller->rx + i;
-		struct cppi_rx_stateram __iomem *rx;
-
-		INIT_LIST_HEAD(&rx_ch->tx_complete);
-
-		rx = tibase + DAVINCI_RXCPPI_STATERAM_OFFSET(i);
-		rx_ch->state_ram = rx;
-		cppi_reset_rx(rx);
-	}
-
-	/* enable individual cppi channels */
-	musb_writel(tibase, DAVINCI_TXCPPI_INTENAB_REG,
-			DAVINCI_DMA_ALL_CHANNELS_ENABLE);
-	musb_writel(tibase, DAVINCI_RXCPPI_INTENAB_REG,
-			DAVINCI_DMA_ALL_CHANNELS_ENABLE);
-
-	/* enable tx/rx CPPI control */
-	musb_writel(tibase, DAVINCI_TXCPPI_CTRL_REG, DAVINCI_DMA_CTRL_ENABLE);
-	musb_writel(tibase, DAVINCI_RXCPPI_CTRL_REG, DAVINCI_DMA_CTRL_ENABLE);
-
-	/* disable RNDIS mode, also host rx RNDIS autorequest */
-	musb_writel(tibase, DAVINCI_RNDIS_REG, 0);
-	musb_writel(tibase, DAVINCI_AUTOREQ_REG, 0);
-}
-
-/*
- *  Stop DMA controller
- *
- *  De-Init the DMA controller as necessary.
- */
-
-static void cppi_controller_stop(struct cppi *controller)
-{
-	void __iomem		*tibase;
-	int			i;
-	struct musb		*musb;
-
-	musb = controller->controller.musb;
-
-	tibase = controller->tibase;
-	/* DISABLE INDIVIDUAL CHANNEL Interrupts */
-	musb_writel(tibase, DAVINCI_TXCPPI_INTCLR_REG,
-			DAVINCI_DMA_ALL_CHANNELS_ENABLE);
-	musb_writel(tibase, DAVINCI_RXCPPI_INTCLR_REG,
-			DAVINCI_DMA_ALL_CHANNELS_ENABLE);
-
-	musb_dbg(musb, "Tearing down RX and TX Channels");
-	for (i = 0; i < ARRAY_SIZE(controller->tx); i++) {
-		/* FIXME restructure of txdma to use bds like rxdma */
-		controller->tx[i].last_processed = NULL;
-		cppi_pool_free(controller->tx + i);
-	}
-	for (i = 0; i < ARRAY_SIZE(controller->rx); i++)
-		cppi_pool_free(controller->rx + i);
-
-	/* in Tx Case proper teardown is supported. We resort to disabling
-	 * Tx/Rx CPPI after cleanup of Tx channels. Before TX teardown is
-	 * complete TX CPPI cannot be disabled.
-	 */
-	/*disable tx/rx cppi */
-	musb_writel(tibase, DAVINCI_TXCPPI_CTRL_REG, DAVINCI_DMA_CTRL_DISABLE);
-	musb_writel(tibase, DAVINCI_RXCPPI_CTRL_REG, DAVINCI_DMA_CTRL_DISABLE);
-}
-
-/* While dma channel is allocated, we only want the core irqs active
- * for fault reports, otherwise we'd get irqs that we don't care about.
- * Except for TX irqs, where dma done != fifo empty and reusable ...
- *
- * NOTE: docs don't say either way, but irq masking **enables** irqs.
- *
- * REVISIT same issue applies to pure PIO usage too, and non-cppi dma...
- */
-static inline void core_rxirq_disable(void __iomem *tibase, unsigned epnum)
-{
-	musb_writel(tibase, DAVINCI_USB_INT_MASK_CLR_REG, 1 << (epnum + 8));
-}
-
-static inline void core_rxirq_enable(void __iomem *tibase, unsigned epnum)
-{
-	musb_writel(tibase, DAVINCI_USB_INT_MASK_SET_REG, 1 << (epnum + 8));
-}
-
-
-/*
- * Allocate a CPPI Channel for DMA.  With CPPI, channels are bound to
- * each transfer direction of a non-control endpoint, so allocating
- * (and deallocating) is mostly a way to notice bad housekeeping on
- * the software side.  We assume the irqs are always active.
- */
-static struct dma_channel *
-cppi_channel_allocate(struct dma_controller *c,
-		struct musb_hw_ep *ep, u8 transmit)
-{
-	struct cppi		*controller;
-	u8			index;
-	struct cppi_channel	*cppi_ch;
-	void __iomem		*tibase;
-	struct musb		*musb;
-
-	controller = container_of(c, struct cppi, controller);
-	tibase = controller->tibase;
-	musb = c->musb;
-
-	/* ep0 doesn't use DMA; remember cppi indices are 0..N-1 */
-	index = ep->epnum - 1;
-
-	/* return the corresponding CPPI Channel Handle, and
-	 * probably disable the non-CPPI irq until we need it.
-	 */
-	if (transmit) {
-		if (index >= ARRAY_SIZE(controller->tx)) {
-			musb_dbg(musb, "no %cX%d CPPI channel", 'T', index);
-			return NULL;
-		}
-		cppi_ch = controller->tx + index;
-	} else {
-		if (index >= ARRAY_SIZE(controller->rx)) {
-			musb_dbg(musb, "no %cX%d CPPI channel", 'R', index);
-			return NULL;
-		}
-		cppi_ch = controller->rx + index;
-		core_rxirq_disable(tibase, ep->epnum);
-	}
-
-	/* REVISIT make this an error later once the same driver code works
-	 * with the other DMA engine too
-	 */
-	if (cppi_ch->hw_ep)
-		musb_dbg(musb, "re-allocating DMA%d %cX channel %p",
-				index, transmit ? 'T' : 'R', cppi_ch);
-	cppi_ch->hw_ep = ep;
-	cppi_ch->channel.status = MUSB_DMA_STATUS_FREE;
-	cppi_ch->channel.max_len = 0x7fffffff;
-
-	musb_dbg(musb, "Allocate CPPI%d %cX", index, transmit ? 'T' : 'R');
-	return &cppi_ch->channel;
-}
-
-/* Release a CPPI Channel.  */
-static void cppi_channel_release(struct dma_channel *channel)
-{
-	struct cppi_channel	*c;
-	void __iomem		*tibase;
-
-	/* REVISIT:  for paranoia, check state and abort if needed... */
-
-	c = container_of(channel, struct cppi_channel, channel);
-	tibase = c->controller->tibase;
-	if (!c->hw_ep)
-		musb_dbg(c->controller->controller.musb,
-			"releasing idle DMA channel %p", c);
-	else if (!c->transmit)
-		core_rxirq_enable(tibase, c->index + 1);
-
-	/* for now, leave its cppi IRQ enabled (we won't trigger it) */
-	c->hw_ep = NULL;
-	channel->status = MUSB_DMA_STATUS_UNKNOWN;
-}
-
-/* Context: controller irqlocked */
-static void
-cppi_dump_rx(int level, struct cppi_channel *c, const char *tag)
-{
-	void __iomem			*base = c->controller->mregs;
-	struct cppi_rx_stateram __iomem	*rx = c->state_ram;
-
-	musb_ep_select(base, c->index + 1);
-
-	musb_dbg(c->controller->controller.musb,
-		"RX DMA%d%s: %d left, csr %04x, "
-		"%08x H%08x S%08x C%08x, "
-		"B%08x L%08x %08x .. %08x",
-		c->index, tag,
-		musb_readl(c->controller->tibase,
-			DAVINCI_RXCPPI_BUFCNT0_REG + 4 * c->index),
-		musb_readw(c->hw_ep->regs, MUSB_RXCSR),
-
-		musb_readl(&rx->rx_skipbytes, 0),
-		musb_readl(&rx->rx_head, 0),
-		musb_readl(&rx->rx_sop, 0),
-		musb_readl(&rx->rx_current, 0),
-
-		musb_readl(&rx->rx_buf_current, 0),
-		musb_readl(&rx->rx_len_len, 0),
-		musb_readl(&rx->rx_cnt_cnt, 0),
-		musb_readl(&rx->rx_complete, 0)
-		);
-}
-
-/* Context: controller irqlocked */
-static void
-cppi_dump_tx(int level, struct cppi_channel *c, const char *tag)
-{
-	void __iomem			*base = c->controller->mregs;
-	struct cppi_tx_stateram __iomem	*tx = c->state_ram;
-
-	musb_ep_select(base, c->index + 1);
-
-	musb_dbg(c->controller->controller.musb,
-		"TX DMA%d%s: csr %04x, "
-		"H%08x S%08x C%08x %08x, "
-		"F%08x L%08x .. %08x",
-		c->index, tag,
-		musb_readw(c->hw_ep->regs, MUSB_TXCSR),
-
-		musb_readl(&tx->tx_head, 0),
-		musb_readl(&tx->tx_buf, 0),
-		musb_readl(&tx->tx_current, 0),
-		musb_readl(&tx->tx_buf_current, 0),
-
-		musb_readl(&tx->tx_info, 0),
-		musb_readl(&tx->tx_rem_len, 0),
-		/* dummy/unused word 6 */
-		musb_readl(&tx->tx_complete, 0)
-		);
-}
-
-/* Context: controller irqlocked */
-static inline void
-cppi_rndis_update(struct cppi_channel *c, int is_rx,
-		void __iomem *tibase, int is_rndis)
-{
-	/* we may need to change the rndis flag for this cppi channel */
-	if (c->is_rndis != is_rndis) {
-		u32	value = musb_readl(tibase, DAVINCI_RNDIS_REG);
-		u32	temp = 1 << (c->index);
-
-		if (is_rx)
-			temp <<= 16;
-		if (is_rndis)
-			value |= temp;
-		else
-			value &= ~temp;
-		musb_writel(tibase, DAVINCI_RNDIS_REG, value);
-		c->is_rndis = is_rndis;
-	}
-}
-
-static void cppi_dump_rxbd(const char *tag, struct cppi_descriptor *bd)
-{
-	pr_debug("RXBD/%s %08x: "
-			"nxt %08x buf %08x off.blen %08x opt.plen %08x\n",
-			tag, bd->dma,
-			bd->hw_next, bd->hw_bufp, bd->hw_off_len,
-			bd->hw_options);
-}
-
-static void cppi_dump_rxq(int level, const char *tag, struct cppi_channel *rx)
-{
-	struct cppi_descriptor	*bd;
-
-	cppi_dump_rx(level, rx, tag);
-	if (rx->last_processed)
-		cppi_dump_rxbd("last", rx->last_processed);
-	for (bd = rx->head; bd; bd = bd->next)
-		cppi_dump_rxbd("active", bd);
-}
-
-
-/* NOTE:  DaVinci autoreq is ignored except for host side "RNDIS" mode RX;
- * so we won't ever use it (see "CPPI RX Woes" below).
- */
-static inline int cppi_autoreq_update(struct cppi_channel *rx,
-		void __iomem *tibase, int onepacket, unsigned n_bds)
-{
-	u32	val;
-
-#ifdef	RNDIS_RX_IS_USABLE
-	u32	tmp;
-	/* assert(is_host_active(musb)) */
-
-	/* start from "AutoReq never" */
-	tmp = musb_readl(tibase, DAVINCI_AUTOREQ_REG);
-	val = tmp & ~((0x3) << (rx->index * 2));
-
-	/* HCD arranged reqpkt for packet #1.  we arrange int
-	 * for all but the last one, maybe in two segments.
-	 */
-	if (!onepacket) {
-#if 0
-		/* use two segments, autoreq "all" then the last "never" */
-		val |= ((0x3) << (rx->index * 2));
-		n_bds--;
-#else
-		/* one segment, autoreq "all-but-last" */
-		val |= ((0x1) << (rx->index * 2));
-#endif
-	}
-
-	if (val != tmp) {
-		int n = 100;
-
-		/* make sure that autoreq is updated before continuing */
-		musb_writel(tibase, DAVINCI_AUTOREQ_REG, val);
-		do {
-			tmp = musb_readl(tibase, DAVINCI_AUTOREQ_REG);
-			if (tmp == val)
-				break;
-			cpu_relax();
-		} while (n-- > 0);
-	}
-#endif
-
-	/* REQPKT is turned off after each segment */
-	if (n_bds && rx->channel.actual_len) {
-		void __iomem	*regs = rx->hw_ep->regs;
-
-		val = musb_readw(regs, MUSB_RXCSR);
-		if (!(val & MUSB_RXCSR_H_REQPKT)) {
-			val |= MUSB_RXCSR_H_REQPKT | MUSB_RXCSR_H_WZC_BITS;
-			musb_writew(regs, MUSB_RXCSR, val);
-			/* flush writebuffer */
-			val = musb_readw(regs, MUSB_RXCSR);
-		}
-	}
-	return n_bds;
-}
-
-
-/* Buffer enqueuing Logic:
- *
- *  - RX builds new queues each time, to help handle routine "early
- *    termination" cases (faults, including errors and short reads)
- *    more correctly.
- *
- *  - for now, TX reuses the same queue of BDs every time
- *
- * REVISIT long term, we want a normal dynamic model.
- * ... the goal will be to append to the
- * existing queue, processing completed "dma buffers" (segments) on the fly.
- *
- * Otherwise we force an IRQ latency between requests, which slows us a lot
- * (especially in "transparent" dma).  Unfortunately that model seems to be
- * inherent in the DMA model from the Mentor code, except in the rare case
- * of transfers big enough (~128+ KB) that we could append "middle" segments
- * in the TX paths.  (RX can't do this, see below.)
- *
- * That's true even in the CPPI- friendly iso case, where most urbs have
- * several small segments provided in a group and where the "packet at a time"
- * "transparent" DMA model is always correct, even on the RX side.
- */
-
-/*
- * CPPI TX:
- * ========
- * TX is a lot more reasonable than RX; it doesn't need to run in
- * irq-per-packet mode very often.  RNDIS mode seems to behave too
- * (except how it handles the exactly-N-packets case).  Building a
- * txdma queue with multiple requests (urb or usb_request) looks
- * like it would work ... but fault handling would need much testing.
- *
- * The main issue with TX mode RNDIS relates to transfer lengths that
- * are an exact multiple of the packet length.  It appears that there's
- * a hiccup in that case (maybe the DMA completes before the ZLP gets
- * written?) boiling down to not being able to rely on CPPI writing any
- * terminating zero length packet before the next transfer is written.
- * So that's punted to PIO; better yet, gadget drivers can avoid it.
- *
- * Plus, there's allegedly an undocumented constraint that rndis transfer
- * length be a multiple of 64 bytes ... but the chip doesn't act that
- * way, and we really don't _want_ that behavior anyway.
- *
- * On TX, "transparent" mode works ... although experiments have shown
- * problems trying to use the SOP/EOP bits in different USB packets.
- *
- * REVISIT try to handle terminating zero length packets using CPPI
- * instead of doing it by PIO after an IRQ.  (Meanwhile, make Ethernet
- * links avoid that issue by forcing them to avoid zlps.)
- */
-static void
-cppi_next_tx_segment(struct musb *musb, struct cppi_channel *tx)
-{
-	unsigned		maxpacket = tx->maxpacket;
-	dma_addr_t		addr = tx->buf_dma + tx->offset;
-	size_t			length = tx->buf_len - tx->offset;
-	struct cppi_descriptor	*bd;
-	unsigned		n_bds;
-	unsigned		i;
-	struct cppi_tx_stateram	__iomem *tx_ram = tx->state_ram;
-	int			rndis;
-
-	/* TX can use the CPPI "rndis" mode, where we can probably fit this
-	 * transfer in one BD and one IRQ.  The only time we would NOT want
-	 * to use it is when hardware constraints prevent it, or if we'd
-	 * trigger the "send a ZLP?" confusion.
-	 */
-	rndis = (maxpacket & 0x3f) == 0
-		&& length > maxpacket
-		&& length < 0xffff
-		&& (length % maxpacket) != 0;
-
-	if (rndis) {
-		maxpacket = length;
-		n_bds = 1;
-	} else {
-		if (length)
-			n_bds = DIV_ROUND_UP(length, maxpacket);
-		else
-			n_bds = 1;
-		n_bds = min(n_bds, (unsigned) NUM_TXCHAN_BD);
-		length = min(n_bds * maxpacket, length);
-	}
-
-	musb_dbg(musb, "TX DMA%d, pktSz %d %s bds %d dma 0x%llx len %u",
-			tx->index,
-			maxpacket,
-			rndis ? "rndis" : "transparent",
-			n_bds,
-			(unsigned long long)addr, length);
-
-	cppi_rndis_update(tx, 0, musb->ctrl_base, rndis);
-
-	/* assuming here that channel_program is called during
-	 * transfer initiation ... current code maintains state
-	 * for one outstanding request only (no queues, not even
-	 * the implicit ones of an iso urb).
-	 */
-
-	bd = tx->freelist;
-	tx->head = bd;
-	tx->last_processed = NULL;
-
-	/* FIXME use BD pool like RX side does, and just queue
-	 * the minimum number for this request.
-	 */
-
-	/* Prepare queue of BDs first, then hand it to hardware.
-	 * All BDs except maybe the last should be of full packet
-	 * size; for RNDIS there _is_ only that last packet.
-	 */
-	for (i = 0; i < n_bds; ) {
-		if (++i < n_bds && bd->next)
-			bd->hw_next = bd->next->dma;
-		else
-			bd->hw_next = 0;
-
-		bd->hw_bufp = tx->buf_dma + tx->offset;
-
-		/* FIXME set EOP only on the last packet,
-		 * SOP only on the first ... avoid IRQs
-		 */
-		if ((tx->offset + maxpacket) <= tx->buf_len) {
-			tx->offset += maxpacket;
-			bd->hw_off_len = maxpacket;
-			bd->hw_options = CPPI_SOP_SET | CPPI_EOP_SET
-				| CPPI_OWN_SET | maxpacket;
-		} else {
-			/* only this one may be a partial USB Packet */
-			u32		partial_len;
-
-			partial_len = tx->buf_len - tx->offset;
-			tx->offset = tx->buf_len;
-			bd->hw_off_len = partial_len;
-
-			bd->hw_options = CPPI_SOP_SET | CPPI_EOP_SET
-				| CPPI_OWN_SET | partial_len;
-			if (partial_len == 0)
-				bd->hw_options |= CPPI_ZERO_SET;
-		}
-
-		musb_dbg(musb, "TXBD %p: nxt %08x buf %08x len %04x opt %08x",
-				bd, bd->hw_next, bd->hw_bufp,
-				bd->hw_off_len, bd->hw_options);
-
-		/* update the last BD enqueued to the list */
-		tx->tail = bd;
-		bd = bd->next;
-	}
-
-	/* BDs live in DMA-coherent memory, but writes might be pending */
-	cpu_drain_writebuffer();
-
-	/* Write to the HeadPtr in state RAM to trigger */
-	musb_writel(&tx_ram->tx_head, 0, (u32)tx->freelist->dma);
-
-	cppi_dump_tx(5, tx, "/S");
-}
-
-/*
- * CPPI RX Woes:
- * =============
- * Consider a 1KB bulk RX buffer in two scenarios:  (a) it's fed two 300 byte
- * packets back-to-back, and (b) it's fed two 512 byte packets back-to-back.
- * (Full speed transfers have similar scenarios.)
- *
- * The correct behavior for Linux is that (a) fills the buffer with 300 bytes,
- * and the next packet goes into a buffer that's queued later; while (b) fills
- * the buffer with 1024 bytes.  How to do that with CPPI?
- *
- * - RX queues in "rndis" mode -- one single BD -- handle (a) correctly, but
- *   (b) loses **BADLY** because nothing (!) happens when that second packet
- *   fills the buffer, much less when a third one arrives.  (Which makes this
- *   not a "true" RNDIS mode.  In the RNDIS protocol short-packet termination
- *   is optional, and it's fine if peripherals -- not hosts! -- pad messages
- *   out to end-of-buffer.  Standard PCI host controller DMA descriptors
- *   implement that mode by default ... which is no accident.)
- *
- * - RX queues in "transparent" mode -- two BDs with 512 bytes each -- have
- *   converse problems:  (b) is handled right, but (a) loses badly.  CPPI RX
- *   ignores SOP/EOP markings and processes both of those BDs; so both packets
- *   are loaded into the buffer (with a 212 byte gap between them), and the next
- *   buffer queued will NOT get its 300 bytes of data. (It seems like SOP/EOP
- *   are intended as outputs for RX queues, not inputs...)
- *
- * - A variant of "transparent" mode -- one BD at a time -- is the only way to
- *   reliably make both cases work, with software handling both cases correctly
- *   and at the significant penalty of needing an IRQ per packet.  (The lack of
- *   I/O overlap can be slightly ameliorated by enabling double buffering.)
- *
- * So how to get rid of IRQ-per-packet?  The transparent multi-BD case could
- * be used in special cases like mass storage, which sets URB_SHORT_NOT_OK
- * (or maybe its peripheral side counterpart) to flag (a) scenarios as errors
- * with guaranteed driver level fault recovery and scrubbing out what's left
- * of that garbaged datastream.
- *
- * But there seems to be no way to identify the cases where CPPI RNDIS mode
- * is appropriate -- which do NOT include RNDIS host drivers, but do include
- * the CDC Ethernet driver! -- and the documentation is incomplete/wrong.
- * So we can't _ever_ use RX RNDIS mode ... except by using a heuristic
- * that applies best on the peripheral side (and which could fail rudely).
- *
- * Leaving only "transparent" mode; we avoid multi-bd modes in almost all
- * cases other than mass storage class.  Otherwise we're correct but slow,
- * since CPPI penalizes our need for a "true RNDIS" default mode.
- */
-
-
-/* Heuristic, intended to kick in for ethernet/rndis peripheral ONLY
- *
- * IFF
- *  (a)	peripheral mode ... since rndis peripherals could pad their
- *	writes to hosts, causing i/o failure; or we'd have to cope with
- *	a largely unknowable variety of host side protocol variants
- *  (b)	and short reads are NOT errors ... since full reads would
- *	cause those same i/o failures
- *  (c)	and read length is
- *	- less than 64KB (max per cppi descriptor)
- *	- not a multiple of 4096 (g_zero default, full reads typical)
- *	- N (>1) packets long, ditto (full reads not EXPECTED)
- * THEN
- *   try rx rndis mode
- *
- * Cost of heuristic failing:  RXDMA wedges at the end of transfers that
- * fill out the whole buffer.  Buggy host side usb network drivers could
- * trigger that, but "in the field" such bugs seem to be all but unknown.
- *
- * So this module parameter lets the heuristic be disabled.  When using
- * gadgetfs, the heuristic will probably need to be disabled.
- */
-static bool cppi_rx_rndis = 1;
-
-module_param(cppi_rx_rndis, bool, 0);
-MODULE_PARM_DESC(cppi_rx_rndis, "enable/disable RX RNDIS heuristic");
-
-
-/**
- * cppi_next_rx_segment - dma read for the next chunk of a buffer
- * @musb: the controller
- * @rx: dma channel
- * @onepacket: true unless caller treats short reads as errors, and
- *	performs fault recovery above usbcore.
- * Context: controller irqlocked
- *
- * See above notes about why we can't use multi-BD RX queues except in
- * rare cases (mass storage class), and can never use the hardware "rndis"
- * mode (since it's not a "true" RNDIS mode) with complete safety..
- *
- * It's ESSENTIAL that callers specify "onepacket" mode unless they kick in
- * code to recover from corrupted datastreams after each short transfer.
- */
-static void
-cppi_next_rx_segment(struct musb *musb, struct cppi_channel *rx, int onepacket)
-{
-	unsigned		maxpacket = rx->maxpacket;
-	dma_addr_t		addr = rx->buf_dma + rx->offset;
-	size_t			length = rx->buf_len - rx->offset;
-	struct cppi_descriptor	*bd, *tail;
-	unsigned		n_bds;
-	unsigned		i;
-	void __iomem		*tibase = musb->ctrl_base;
-	int			is_rndis = 0;
-	struct cppi_rx_stateram	__iomem *rx_ram = rx->state_ram;
-	struct cppi_descriptor	*d;
-
-	if (onepacket) {
-		/* almost every USB driver, host or peripheral side */
-		n_bds = 1;
-
-		/* maybe apply the heuristic above */
-		if (cppi_rx_rndis
-				&& is_peripheral_active(musb)
-				&& length > maxpacket
-				&& (length & ~0xffff) == 0
-				&& (length & 0x0fff) != 0
-				&& (length & (maxpacket - 1)) == 0) {
-			maxpacket = length;
-			is_rndis = 1;
-		}
-	} else {
-		/* virtually nothing except mass storage class */
-		if (length > 0xffff) {
-			n_bds = 0xffff / maxpacket;
-			length = n_bds * maxpacket;
-		} else {
-			n_bds = DIV_ROUND_UP(length, maxpacket);
-		}
-		if (n_bds == 1)
-			onepacket = 1;
-		else
-			n_bds = min(n_bds, (unsigned) NUM_RXCHAN_BD);
-	}
-
-	/* In host mode, autorequest logic can generate some IN tokens; it's
-	 * tricky since we can't leave REQPKT set in RXCSR after the transfer
-	 * finishes. So:  multipacket transfers involve two or more segments.
-	 * And always at least two IRQs ... RNDIS mode is not an option.
-	 */
-	if (is_host_active(musb))
-		n_bds = cppi_autoreq_update(rx, tibase, onepacket, n_bds);
-
-	cppi_rndis_update(rx, 1, musb->ctrl_base, is_rndis);
-
-	length = min(n_bds * maxpacket, length);
-
-	musb_dbg(musb, "RX DMA%d seg, maxp %d %s bds %d (cnt %d) "
-			"dma 0x%llx len %u %u/%u",
-			rx->index, maxpacket,
-			onepacket
-				? (is_rndis ? "rndis" : "onepacket")
-				: "multipacket",
-			n_bds,
-			musb_readl(tibase,
-				DAVINCI_RXCPPI_BUFCNT0_REG + (rx->index * 4))
-					& 0xffff,
-			(unsigned long long)addr, length,
-			rx->channel.actual_len, rx->buf_len);
-
-	/* only queue one segment at a time, since the hardware prevents
-	 * correct queue shutdown after unexpected short packets
-	 */
-	bd = cppi_bd_alloc(rx);
-	rx->head = bd;
-
-	/* Build BDs for all packets in this segment */
-	for (i = 0, tail = NULL; bd && i < n_bds; i++, tail = bd) {
-		u32	bd_len;
-
-		if (i) {
-			bd = cppi_bd_alloc(rx);
-			if (!bd)
-				break;
-			tail->next = bd;
-			tail->hw_next = bd->dma;
-		}
-		bd->hw_next = 0;
-
-		/* all but the last packet will be maxpacket size */
-		if (maxpacket < length)
-			bd_len = maxpacket;
-		else
-			bd_len = length;
-
-		bd->hw_bufp = addr;
-		addr += bd_len;
-		rx->offset += bd_len;
-
-		bd->hw_off_len = (0 /*offset*/ << 16) + bd_len;
-		bd->buflen = bd_len;
-
-		bd->hw_options = CPPI_OWN_SET | (i == 0 ? length : 0);
-		length -= bd_len;
-	}
-
-	/* we always expect at least one reusable BD! */
-	if (!tail) {
-		WARNING("rx dma%d -- no BDs? need %d\n", rx->index, n_bds);
-		return;
-	} else if (i < n_bds)
-		WARNING("rx dma%d -- only %d of %d BDs\n", rx->index, i, n_bds);
-
-	tail->next = NULL;
-	tail->hw_next = 0;
-
-	bd = rx->head;
-	rx->tail = tail;
-
-	/* short reads and other faults should terminate this entire
-	 * dma segment.  we want one "dma packet" per dma segment, not
-	 * one per USB packet, terminating the whole queue at once...
-	 * NOTE that current hardware seems to ignore SOP and EOP.
-	 */
-	bd->hw_options |= CPPI_SOP_SET;
-	tail->hw_options |= CPPI_EOP_SET;
-
-	for (d = rx->head; d; d = d->next)
-		cppi_dump_rxbd("S", d);
-
-	/* in case the preceding transfer left some state... */
-	tail = rx->last_processed;
-	if (tail) {
-		tail->next = bd;
-		tail->hw_next = bd->dma;
-	}
-
-	core_rxirq_enable(tibase, rx->index + 1);
-
-	/* BDs live in DMA-coherent memory, but writes might be pending */
-	cpu_drain_writebuffer();
-
-	/* REVISIT specs say to write this AFTER the BUFCNT register
-	 * below ... but that loses badly.
-	 */
-	musb_writel(&rx_ram->rx_head, 0, bd->dma);
-
-	/* bufferCount must be at least 3, and zeroes on completion
-	 * unless it underflows below zero, or stops at two, or keeps
-	 * growing ... grr.
-	 */
-	i = musb_readl(tibase,
-			DAVINCI_RXCPPI_BUFCNT0_REG + (rx->index * 4))
-			& 0xffff;
-
-	if (!i)
-		musb_writel(tibase,
-			DAVINCI_RXCPPI_BUFCNT0_REG + (rx->index * 4),
-			n_bds + 2);
-	else if (n_bds > (i - 3))
-		musb_writel(tibase,
-			DAVINCI_RXCPPI_BUFCNT0_REG + (rx->index * 4),
-			n_bds - (i - 3));
-
-	i = musb_readl(tibase,
-			DAVINCI_RXCPPI_BUFCNT0_REG + (rx->index * 4))
-			& 0xffff;
-	if (i < (2 + n_bds)) {
-		musb_dbg(musb, "bufcnt%d underrun - %d (for %d)",
-					rx->index, i, n_bds);
-		musb_writel(tibase,
-			DAVINCI_RXCPPI_BUFCNT0_REG + (rx->index * 4),
-			n_bds + 2);
-	}
-
-	cppi_dump_rx(4, rx, "/S");
-}
-
-/**
- * cppi_channel_program - program channel for data transfer
- * @ch: the channel
- * @maxpacket: max packet size
- * @mode: For RX, 1 unless the usb protocol driver promised to treat
- *	all short reads as errors and kick in high level fault recovery.
- *	For TX, ignored because of RNDIS mode races/glitches.
- * @dma_addr: dma address of buffer
- * @len: length of buffer
- * Context: controller irqlocked
- */
-static int cppi_channel_program(struct dma_channel *ch,
-		u16 maxpacket, u8 mode,
-		dma_addr_t dma_addr, u32 len)
-{
-	struct cppi_channel	*cppi_ch;
-	struct cppi		*controller;
-	struct musb		*musb;
-
-	cppi_ch = container_of(ch, struct cppi_channel, channel);
-	controller = cppi_ch->controller;
-	musb = controller->controller.musb;
-
-	switch (ch->status) {
-	case MUSB_DMA_STATUS_BUS_ABORT:
-	case MUSB_DMA_STATUS_CORE_ABORT:
-		/* fault irq handler should have handled cleanup */
-		WARNING("%cX DMA%d not cleaned up after abort!\n",
-				cppi_ch->transmit ? 'T' : 'R',
-				cppi_ch->index);
-		/* WARN_ON(1); */
-		break;
-	case MUSB_DMA_STATUS_BUSY:
-		WARNING("program active channel?  %cX DMA%d\n",
-				cppi_ch->transmit ? 'T' : 'R',
-				cppi_ch->index);
-		/* WARN_ON(1); */
-		break;
-	case MUSB_DMA_STATUS_UNKNOWN:
-		musb_dbg(musb, "%cX DMA%d not allocated!",
-				cppi_ch->transmit ? 'T' : 'R',
-				cppi_ch->index);
-		fallthrough;
-	case MUSB_DMA_STATUS_FREE:
-		break;
-	}
-
-	ch->status = MUSB_DMA_STATUS_BUSY;
-
-	/* set transfer parameters, then queue up its first segment */
-	cppi_ch->buf_dma = dma_addr;
-	cppi_ch->offset = 0;
-	cppi_ch->maxpacket = maxpacket;
-	cppi_ch->buf_len = len;
-	cppi_ch->channel.actual_len = 0;
-
-	/* TX channel? or RX? */
-	if (cppi_ch->transmit)
-		cppi_next_tx_segment(musb, cppi_ch);
-	else
-		cppi_next_rx_segment(musb, cppi_ch, mode);
-
-	return true;
-}
-
-static bool cppi_rx_scan(struct cppi *cppi, unsigned ch)
-{
-	struct cppi_channel		*rx = &cppi->rx[ch];
-	struct cppi_rx_stateram __iomem	*state = rx->state_ram;
-	struct cppi_descriptor		*bd;
-	struct cppi_descriptor		*last = rx->last_processed;
-	bool				completed = false;
-	bool				acked = false;
-	int				i;
-	dma_addr_t			safe2ack;
-	void __iomem			*regs = rx->hw_ep->regs;
-	struct musb			*musb = cppi->controller.musb;
-
-	cppi_dump_rx(6, rx, "/K");
-
-	bd = last ? last->next : rx->head;
-	if (!bd)
-		return false;
-
-	/* run through all completed BDs */
-	for (i = 0, safe2ack = musb_readl(&state->rx_complete, 0);
-			(safe2ack || completed) && bd && i < NUM_RXCHAN_BD;
-			i++, bd = bd->next) {
-		u16	len;
-
-		/* catch latest BD writes from CPPI */
-		rmb();
-		if (!completed && (bd->hw_options & CPPI_OWN_SET))
-			break;
-
-		musb_dbg(musb, "C/RXBD %llx: nxt %08x buf %08x "
-			"off.len %08x opt.len %08x (%d)",
-			(unsigned long long)bd->dma, bd->hw_next, bd->hw_bufp,
-			bd->hw_off_len, bd->hw_options,
-			rx->channel.actual_len);
-
-		/* actual packet received length */
-		if ((bd->hw_options & CPPI_SOP_SET) && !completed)
-			len = bd->hw_off_len & CPPI_RECV_PKTLEN_MASK;
-		else
-			len = 0;
-
-		if (bd->hw_options & CPPI_EOQ_MASK)
-			completed = true;
-
-		if (!completed && len < bd->buflen) {
-			/* NOTE:  when we get a short packet, RXCSR_H_REQPKT
-			 * must have been cleared, and no more DMA packets may
-			 * active be in the queue... TI docs didn't say, but
-			 * CPPI ignores those BDs even though OWN is still set.
-			 */
-			completed = true;
-			musb_dbg(musb, "rx short %d/%d (%d)",
-					len, bd->buflen,
-					rx->channel.actual_len);
-		}
-
-		/* If we got here, we expect to ack at least one BD; meanwhile
-		 * CPPI may completing other BDs while we scan this list...
-		 *
-		 * RACE: we can notice OWN cleared before CPPI raises the
-		 * matching irq by writing that BD as the completion pointer.
-		 * In such cases, stop scanning and wait for the irq, avoiding
-		 * lost acks and states where BD ownership is unclear.
-		 */
-		if (bd->dma == safe2ack) {
-			musb_writel(&state->rx_complete, 0, safe2ack);
-			safe2ack = musb_readl(&state->rx_complete, 0);
-			acked = true;
-			if (bd->dma == safe2ack)
-				safe2ack = 0;
-		}
-
-		rx->channel.actual_len += len;
-
-		cppi_bd_free(rx, last);
-		last = bd;
-
-		/* stop scanning on end-of-segment */
-		if (bd->hw_next == 0)
-			completed = true;
-	}
-	rx->last_processed = last;
-
-	/* dma abort, lost ack, or ... */
-	if (!acked && last) {
-		int	csr;
-
-		if (safe2ack == 0 || safe2ack == rx->last_processed->dma)
-			musb_writel(&state->rx_complete, 0, safe2ack);
-		if (safe2ack == 0) {
-			cppi_bd_free(rx, last);
-			rx->last_processed = NULL;
-
-			/* if we land here on the host side, H_REQPKT will
-			 * be clear and we need to restart the queue...
-			 */
-			WARN_ON(rx->head);
-		}
-		musb_ep_select(cppi->mregs, rx->index + 1);
-		csr = musb_readw(regs, MUSB_RXCSR);
-		if (csr & MUSB_RXCSR_DMAENAB) {
-			musb_dbg(musb, "list%d %p/%p, last %llx%s, csr %04x",
-				rx->index,
-				rx->head, rx->tail,
-				rx->last_processed
-					? (unsigned long long)
-						rx->last_processed->dma
-					: 0,
-				completed ? ", completed" : "",
-				csr);
-			cppi_dump_rxq(4, "/what?", rx);
-		}
-	}
-	if (!completed) {
-		int	csr;
-
-		rx->head = bd;
-
-		/* REVISIT seems like "autoreq all but EOP" doesn't...
-		 * setting it here "should" be racey, but seems to work
-		 */
-		csr = musb_readw(rx->hw_ep->regs, MUSB_RXCSR);
-		if (is_host_active(cppi->controller.musb)
-				&& bd
-				&& !(csr & MUSB_RXCSR_H_REQPKT)) {
-			csr |= MUSB_RXCSR_H_REQPKT;
-			musb_writew(regs, MUSB_RXCSR,
-					MUSB_RXCSR_H_WZC_BITS | csr);
-			csr = musb_readw(rx->hw_ep->regs, MUSB_RXCSR);
-		}
-	} else {
-		rx->head = NULL;
-		rx->tail = NULL;
-	}
-
-	cppi_dump_rx(6, rx, completed ? "/completed" : "/cleaned");
-	return completed;
-}
-
-irqreturn_t cppi_interrupt(int irq, void *dev_id)
-{
-	struct musb		*musb = dev_id;
-	struct cppi		*cppi;
-	void __iomem		*tibase;
-	struct musb_hw_ep	*hw_ep = NULL;
-	u32			rx, tx;
-	int			i, index;
-	unsigned long		flags;
-
-	cppi = container_of(musb->dma_controller, struct cppi, controller);
-	if (cppi->irq)
-		spin_lock_irqsave(&musb->lock, flags);
-
-	tibase = musb->ctrl_base;
-
-	tx = musb_readl(tibase, DAVINCI_TXCPPI_MASKED_REG);
-	rx = musb_readl(tibase, DAVINCI_RXCPPI_MASKED_REG);
-
-	if (!tx && !rx) {
-		if (cppi->irq)
-			spin_unlock_irqrestore(&musb->lock, flags);
-		return IRQ_NONE;
-	}
-
-	musb_dbg(musb, "CPPI IRQ Tx%x Rx%x", tx, rx);
-
-	/* process TX channels */
-	for (index = 0; tx; tx = tx >> 1, index++) {
-		struct cppi_channel		*tx_ch;
-		struct cppi_tx_stateram __iomem	*tx_ram;
-		bool				completed = false;
-		struct cppi_descriptor		*bd;
-
-		if (!(tx & 1))
-			continue;
-
-		tx_ch = cppi->tx + index;
-		tx_ram = tx_ch->state_ram;
-
-		/* FIXME  need a cppi_tx_scan() routine, which
-		 * can also be called from abort code
-		 */
-
-		cppi_dump_tx(5, tx_ch, "/E");
-
-		bd = tx_ch->head;
-
-		/*
-		 * If Head is null then this could mean that a abort interrupt
-		 * that needs to be acknowledged.
-		 */
-		if (NULL == bd) {
-			musb_dbg(musb, "null BD");
-			musb_writel(&tx_ram->tx_complete, 0, 0);
-			continue;
-		}
-
-		/* run through all completed BDs */
-		for (i = 0; !completed && bd && i < NUM_TXCHAN_BD;
-				i++, bd = bd->next) {
-			u16	len;
-
-			/* catch latest BD writes from CPPI */
-			rmb();
-			if (bd->hw_options & CPPI_OWN_SET)
-				break;
-
-			musb_dbg(musb, "C/TXBD %p n %x b %x off %x opt %x",
-					bd, bd->hw_next, bd->hw_bufp,
-					bd->hw_off_len, bd->hw_options);
-
-			len = bd->hw_off_len & CPPI_BUFFER_LEN_MASK;
-			tx_ch->channel.actual_len += len;
-
-			tx_ch->last_processed = bd;
-
-			/* write completion register to acknowledge
-			 * processing of completed BDs, and possibly
-			 * release the IRQ; EOQ might not be set ...
-			 *
-			 * REVISIT use the same ack strategy as rx
-			 *
-			 * REVISIT have observed bit 18 set; huh??
-			 */
-			/* if ((bd->hw_options & CPPI_EOQ_MASK)) */
-				musb_writel(&tx_ram->tx_complete, 0, bd->dma);
-
-			/* stop scanning on end-of-segment */
-			if (bd->hw_next == 0)
-				completed = true;
-		}
-
-		/* on end of segment, maybe go to next one */
-		if (completed) {
-			/* cppi_dump_tx(4, tx_ch, "/complete"); */
-
-			/* transfer more, or report completion */
-			if (tx_ch->offset >= tx_ch->buf_len) {
-				tx_ch->head = NULL;
-				tx_ch->tail = NULL;
-				tx_ch->channel.status = MUSB_DMA_STATUS_FREE;
-
-				hw_ep = tx_ch->hw_ep;
-
-				musb_dma_completion(musb, index + 1, 1);
-
-			} else {
-				/* Bigger transfer than we could fit in
-				 * that first batch of descriptors...
-				 */
-				cppi_next_tx_segment(musb, tx_ch);
-			}
-		} else
-			tx_ch->head = bd;
-	}
-
-	/* Start processing the RX block */
-	for (index = 0; rx; rx = rx >> 1, index++) {
-
-		if (rx & 1) {
-			struct cppi_channel		*rx_ch;
-
-			rx_ch = cppi->rx + index;
-
-			/* let incomplete dma segments finish */
-			if (!cppi_rx_scan(cppi, index))
-				continue;
-
-			/* start another dma segment if needed */
-			if (rx_ch->channel.actual_len != rx_ch->buf_len
-					&& rx_ch->channel.actual_len
-						== rx_ch->offset) {
-				cppi_next_rx_segment(musb, rx_ch, 1);
-				continue;
-			}
-
-			/* all segments completed! */
-			rx_ch->channel.status = MUSB_DMA_STATUS_FREE;
-
-			hw_ep = rx_ch->hw_ep;
-
-			core_rxirq_disable(tibase, index + 1);
-			musb_dma_completion(musb, index + 1, 0);
-		}
-	}
-
-	/* write to CPPI EOI register to re-enable interrupts */
-	musb_writel(tibase, DAVINCI_CPPI_EOI_REG, 0);
-
-	if (cppi->irq)
-		spin_unlock_irqrestore(&musb->lock, flags);
-
-	return IRQ_HANDLED;
-}
-EXPORT_SYMBOL_GPL(cppi_interrupt);
-
-/* Instantiate a software object representing a DMA controller. */
-struct dma_controller *
-cppi_dma_controller_create(struct musb *musb, void __iomem *mregs)
-{
-	struct cppi		*controller;
-	struct device		*dev = musb->controller;
-	struct platform_device	*pdev = to_platform_device(dev);
-	int			irq = platform_get_irq_byname(pdev, "dma");
-
-	controller = kzalloc(sizeof *controller, GFP_KERNEL);
-	if (!controller)
-		return NULL;
-
-	controller->mregs = mregs;
-	controller->tibase = mregs - DAVINCI_BASE_OFFSET;
-
-	controller->controller.musb = musb;
-	controller->controller.channel_alloc = cppi_channel_allocate;
-	controller->controller.channel_release = cppi_channel_release;
-	controller->controller.channel_program = cppi_channel_program;
-	controller->controller.channel_abort = cppi_channel_abort;
-
-	/* NOTE: allocating from on-chip SRAM would give the least
-	 * contention for memory access, if that ever matters here.
-	 */
-
-	/* setup BufferPool */
-	controller->pool = dma_pool_create("cppi",
-			controller->controller.musb->controller,
-			sizeof(struct cppi_descriptor),
-			CPPI_DESCRIPTOR_ALIGN, 0);
-	if (!controller->pool) {
-		kfree(controller);
-		return NULL;
-	}
-
-	if (irq > 0) {
-		if (request_irq(irq, cppi_interrupt, 0, "cppi-dma", musb)) {
-			dev_err(dev, "request_irq %d failed!\n", irq);
-			musb_dma_controller_destroy(&controller->controller);
-			return NULL;
-		}
-		controller->irq = irq;
-	}
-
-	cppi_controller_start(controller);
-	return &controller->controller;
-}
-EXPORT_SYMBOL_GPL(cppi_dma_controller_create);
-
-/*
- *  Destroy a previously-instantiated DMA controller.
- */
-void cppi_dma_controller_destroy(struct dma_controller *c)
-{
-	struct cppi	*cppi;
-
-	cppi = container_of(c, struct cppi, controller);
-
-	cppi_controller_stop(cppi);
-
-	if (cppi->irq)
-		free_irq(cppi->irq, cppi->controller.musb);
-
-	/* assert:  caller stopped the controller first */
-	dma_pool_destroy(cppi->pool);
-
-	kfree(cppi);
-}
-EXPORT_SYMBOL_GPL(cppi_dma_controller_destroy);
-
-/*
- * Context: controller irqlocked, endpoint selected
- */
-static int cppi_channel_abort(struct dma_channel *channel)
-{
-	struct cppi_channel	*cppi_ch;
-	struct cppi		*controller;
-	void __iomem		*mbase;
-	void __iomem		*tibase;
-	void __iomem		*regs;
-	u32			value;
-	struct cppi_descriptor	*queue;
-
-	cppi_ch = container_of(channel, struct cppi_channel, channel);
-
-	controller = cppi_ch->controller;
-
-	switch (channel->status) {
-	case MUSB_DMA_STATUS_BUS_ABORT:
-	case MUSB_DMA_STATUS_CORE_ABORT:
-		/* from RX or TX fault irq handler */
-	case MUSB_DMA_STATUS_BUSY:
-		/* the hardware needs shutting down */
-		regs = cppi_ch->hw_ep->regs;
-		break;
-	case MUSB_DMA_STATUS_UNKNOWN:
-	case MUSB_DMA_STATUS_FREE:
-		return 0;
-	default:
-		return -EINVAL;
-	}
-
-	if (!cppi_ch->transmit && cppi_ch->head)
-		cppi_dump_rxq(3, "/abort", cppi_ch);
-
-	mbase = controller->mregs;
-	tibase = controller->tibase;
-
-	queue = cppi_ch->head;
-	cppi_ch->head = NULL;
-	cppi_ch->tail = NULL;
-
-	/* REVISIT should rely on caller having done this,
-	 * and caller should rely on us not changing it.
-	 * peripheral code is safe ... check host too.
-	 */
-	musb_ep_select(mbase, cppi_ch->index + 1);
-
-	if (cppi_ch->transmit) {
-		struct cppi_tx_stateram __iomem *tx_ram;
-		/* REVISIT put timeouts on these controller handshakes */
-
-		cppi_dump_tx(6, cppi_ch, " (teardown)");
-
-		/* teardown DMA engine then usb core */
-		do {
-			value = musb_readl(tibase, DAVINCI_TXCPPI_TEAR_REG);
-		} while (!(value & CPPI_TEAR_READY));
-		musb_writel(tibase, DAVINCI_TXCPPI_TEAR_REG, cppi_ch->index);
-
-		tx_ram = cppi_ch->state_ram;
-		do {
-			value = musb_readl(&tx_ram->tx_complete, 0);
-		} while (0xFFFFFFFC != value);
-
-		/* FIXME clean up the transfer state ... here?
-		 * the completion routine should get called with
-		 * an appropriate status code.
-		 */
-
-		value = musb_readw(regs, MUSB_TXCSR);
-		value &= ~MUSB_TXCSR_DMAENAB;
-		value |= MUSB_TXCSR_FLUSHFIFO;
-		musb_writew(regs, MUSB_TXCSR, value);
-		musb_writew(regs, MUSB_TXCSR, value);
-
-		/*
-		 * 1. Write to completion Ptr value 0x1(bit 0 set)
-		 *    (write back mode)
-		 * 2. Wait for abort interrupt and then put the channel in
-		 *    compare mode by writing 1 to the tx_complete register.
-		 */
-		cppi_reset_tx(tx_ram, 1);
-		cppi_ch->head = NULL;
-		musb_writel(&tx_ram->tx_complete, 0, 1);
-		cppi_dump_tx(5, cppi_ch, " (done teardown)");
-
-		/* REVISIT tx side _should_ clean up the same way
-		 * as the RX side ... this does no cleanup at all!
-		 */
-
-	} else /* RX */ {
-		u16			csr;
-
-		/* NOTE: docs don't guarantee any of this works ...  we
-		 * expect that if the usb core stops telling the cppi core
-		 * to pull more data from it, then it'll be safe to flush
-		 * current RX DMA state iff any pending fifo transfer is done.
-		 */
-
-		core_rxirq_disable(tibase, cppi_ch->index + 1);
-
-		/* for host, ensure ReqPkt is never set again */
-		if (is_host_active(cppi_ch->controller->controller.musb)) {
-			value = musb_readl(tibase, DAVINCI_AUTOREQ_REG);
-			value &= ~((0x3) << (cppi_ch->index * 2));
-			musb_writel(tibase, DAVINCI_AUTOREQ_REG, value);
-		}
-
-		csr = musb_readw(regs, MUSB_RXCSR);
-
-		/* for host, clear (just) ReqPkt at end of current packet(s) */
-		if (is_host_active(cppi_ch->controller->controller.musb)) {
-			csr |= MUSB_RXCSR_H_WZC_BITS;
-			csr &= ~MUSB_RXCSR_H_REQPKT;
-		} else
-			csr |= MUSB_RXCSR_P_WZC_BITS;
-
-		/* clear dma enable */
-		csr &= ~(MUSB_RXCSR_DMAENAB);
-		musb_writew(regs, MUSB_RXCSR, csr);
-		csr = musb_readw(regs, MUSB_RXCSR);
-
-		/* Quiesce: wait for current dma to finish (if not cleanup).
-		 * We can't use bit zero of stateram->rx_sop, since that
-		 * refers to an entire "DMA packet" not just emptying the
-		 * current fifo.  Most segments need multiple usb packets.
-		 */
-		if (channel->status == MUSB_DMA_STATUS_BUSY)
-			udelay(50);
-
-		/* scan the current list, reporting any data that was
-		 * transferred and acking any IRQ
-		 */
-		cppi_rx_scan(controller, cppi_ch->index);
-
-		/* clobber the existing state once it's idle
-		 *
-		 * NOTE:  arguably, we should also wait for all the other
-		 * RX channels to quiesce (how??) and then temporarily
-		 * disable RXCPPI_CTRL_REG ... but it seems that we can
-		 * rely on the controller restarting from state ram, with
-		 * only RXCPPI_BUFCNT state being bogus.  BUFCNT will
-		 * correct itself after the next DMA transfer though.
-		 *
-		 * REVISIT does using rndis mode change that?
-		 */
-		cppi_reset_rx(cppi_ch->state_ram);
-
-		/* next DMA request _should_ load cppi head ptr */
-
-		/* ... we don't "free" that list, only mutate it in place.  */
-		cppi_dump_rx(5, cppi_ch, " (done abort)");
-
-		/* clean up previously pending bds */
-		cppi_bd_free(cppi_ch, cppi_ch->last_processed);
-		cppi_ch->last_processed = NULL;
-
-		while (queue) {
-			struct cppi_descriptor	*tmp = queue->next;
-
-			cppi_bd_free(cppi_ch, queue);
-			queue = tmp;
-		}
-	}
-
-	channel->status = MUSB_DMA_STATUS_FREE;
-	cppi_ch->buf_dma = 0;
-	cppi_ch->offset = 0;
-	cppi_ch->buf_len = 0;
-	cppi_ch->maxpacket = 0;
-	return 0;
-}
-
-/* TBD Queries:
- *
- * Power Management ... probably turn off cppi during suspend, restart;
- * check state ram?  Clocking is presumably shared with usb core.
- */
diff --git a/drivers/usb/musb/davinci.c b/drivers/usb/musb/davinci.c
deleted file mode 100644
index 704435526394..000000000000
--- a/drivers/usb/musb/davinci.c
+++ /dev/null
@@ -1,606 +0,0 @@ 
-// SPDX-License-Identifier: GPL-2.0
-/*
- * Copyright (C) 2005-2006 by Texas Instruments
- *
- * This file is part of the Inventra Controller Driver for Linux.
- */
-
-#include <linux/module.h>
-#include <linux/kernel.h>
-#include <linux/sched.h>
-#include <linux/list.h>
-#include <linux/delay.h>
-#include <linux/clk.h>
-#include <linux/err.h>
-#include <linux/io.h>
-#include <linux/gpio/consumer.h>
-#include <linux/platform_device.h>
-#include <linux/dma-mapping.h>
-#include <linux/usb/usb_phy_generic.h>
-
-#include <mach/cputype.h>
-#include <mach/hardware.h>
-
-#include <asm/mach-types.h>
-
-#include "musb_core.h"
-
-#include "davinci.h"
-#include "cppi_dma.h"
-
-
-#define USB_PHY_CTRL	IO_ADDRESS(USBPHY_CTL_PADDR)
-#define DM355_DEEPSLEEP	IO_ADDRESS(DM355_DEEPSLEEP_PADDR)
-
-struct davinci_glue {
-	struct device		*dev;
-	struct platform_device	*musb;
-	struct clk		*clk;
-	bool			vbus_state;
-	struct gpio_desc	*vbus;
-	struct work_struct	vbus_work;
-};
-
-/* REVISIT (PM) we should be able to keep the PHY in low power mode most
- * of the time (24 MHZ oscillator and PLL off, etc) by setting POWER.D0
- * and, when in host mode, autosuspending idle root ports... PHYPLLON
- * (overriding SUSPENDM?) then likely needs to stay off.
- */
-
-static inline void phy_on(void)
-{
-	u32	phy_ctrl = __raw_readl(USB_PHY_CTRL);
-
-	/* power everything up; start the on-chip PHY and its PLL */
-	phy_ctrl &= ~(USBPHY_OSCPDWN | USBPHY_OTGPDWN | USBPHY_PHYPDWN);
-	phy_ctrl |= USBPHY_SESNDEN | USBPHY_VBDTCTEN | USBPHY_PHYPLLON;
-	__raw_writel(phy_ctrl, USB_PHY_CTRL);
-
-	/* wait for PLL to lock before proceeding */
-	while ((__raw_readl(USB_PHY_CTRL) & USBPHY_PHYCLKGD) == 0)
-		cpu_relax();
-}
-
-static inline void phy_off(void)
-{
-	u32	phy_ctrl = __raw_readl(USB_PHY_CTRL);
-
-	/* powerdown the on-chip PHY, its PLL, and the OTG block */
-	phy_ctrl &= ~(USBPHY_SESNDEN | USBPHY_VBDTCTEN | USBPHY_PHYPLLON);
-	phy_ctrl |= USBPHY_OSCPDWN | USBPHY_OTGPDWN | USBPHY_PHYPDWN;
-	__raw_writel(phy_ctrl, USB_PHY_CTRL);
-}
-
-static int dma_off = 1;
-
-static void davinci_musb_enable(struct musb *musb)
-{
-	u32	tmp, old, val;
-
-	/* workaround:  setup irqs through both register sets */
-	tmp = (musb->epmask & DAVINCI_USB_TX_ENDPTS_MASK)
-			<< DAVINCI_USB_TXINT_SHIFT;
-	musb_writel(musb->ctrl_base, DAVINCI_USB_INT_MASK_SET_REG, tmp);
-	old = tmp;
-	tmp = (musb->epmask & (0xfffe & DAVINCI_USB_RX_ENDPTS_MASK))
-			<< DAVINCI_USB_RXINT_SHIFT;
-	musb_writel(musb->ctrl_base, DAVINCI_USB_INT_MASK_SET_REG, tmp);
-	tmp |= old;
-
-	val = ~MUSB_INTR_SOF;
-	tmp |= ((val & 0x01ff) << DAVINCI_USB_USBINT_SHIFT);
-	musb_writel(musb->ctrl_base, DAVINCI_USB_INT_MASK_SET_REG, tmp);
-
-	if (is_dma_capable() && !dma_off)
-		printk(KERN_WARNING "%s %s: dma not reactivated\n",
-				__FILE__, __func__);
-	else
-		dma_off = 0;
-
-	/* force a DRVVBUS irq so we can start polling for ID change */
-	musb_writel(musb->ctrl_base, DAVINCI_USB_INT_SET_REG,
-			DAVINCI_INTR_DRVVBUS << DAVINCI_USB_USBINT_SHIFT);
-}
-
-/*
- * Disable the HDRC and flush interrupts
- */
-static void davinci_musb_disable(struct musb *musb)
-{
-	/* because we don't set CTRLR.UINT, "important" to:
-	 *  - not read/write INTRUSB/INTRUSBE
-	 *  - (except during initial setup, as workaround)
-	 *  - use INTSETR/INTCLRR instead
-	 */
-	musb_writel(musb->ctrl_base, DAVINCI_USB_INT_MASK_CLR_REG,
-			  DAVINCI_USB_USBINT_MASK
-			| DAVINCI_USB_TXINT_MASK
-			| DAVINCI_USB_RXINT_MASK);
-	musb_writel(musb->ctrl_base, DAVINCI_USB_EOI_REG, 0);
-
-	if (is_dma_capable() && !dma_off)
-		WARNING("dma still active\n");
-}
-
-
-#define	portstate(stmt)		stmt
-
-/*
- * VBUS SWITCHING IS BOARD-SPECIFIC ... at least for the DM6446 EVM,
- * which doesn't wire DRVVBUS to the FET that switches it.  Unclear
- * if that's a problem with the DM6446 chip or just with that board.
- *
- * In either case, the DM355 EVM automates DRVVBUS the normal way,
- * when J10 is out, and TI documents it as handling OTG.
- */
-
-/* I2C operations are always synchronous, and require a task context.
- * With unloaded systems, using the shared workqueue seems to suffice
- * to satisfy the 100msec A_WAIT_VRISE timeout...
- */
-static void evm_deferred_drvvbus(struct work_struct *work)
-{
-	struct davinci_glue *glue = container_of(work, struct davinci_glue,
-						 vbus_work);
-
-	gpiod_set_value_cansleep(glue->vbus, glue->vbus_state);
-	glue->vbus_state = !glue->vbus_state;
-}
-
-static void davinci_musb_source_power(struct musb *musb, int is_on,
-				      int immediate)
-{
-	struct davinci_glue *glue = dev_get_drvdata(musb->controller->parent);
-
-	/* This GPIO handling is entirely optional */
-	if (!glue->vbus)
-		return;
-
-	if (is_on)
-		is_on = 1;
-
-	if (glue->vbus_state == is_on)
-		return;
-	/* 0/1 vs "-1 == unknown/init" */
-	glue->vbus_state = !is_on;
-
-	if (machine_is_davinci_evm()) {
-		if (immediate)
-			gpiod_set_value_cansleep(glue->vbus, glue->vbus_state);
-		else
-			schedule_work(&glue->vbus_work);
-	}
-	if (immediate)
-		glue->vbus_state = is_on;
-}
-
-static void davinci_musb_set_vbus(struct musb *musb, int is_on)
-{
-	WARN_ON(is_on && is_peripheral_active(musb));
-	davinci_musb_source_power(musb, is_on, 0);
-}
-
-
-#define	POLL_SECONDS	2
-
-static void otg_timer(struct timer_list *t)
-{
-	struct musb		*musb = from_timer(musb, t, dev_timer);
-	void __iomem		*mregs = musb->mregs;
-	u8			devctl;
-	unsigned long		flags;
-
-	/* We poll because DaVinci's won't expose several OTG-critical
-	* status change events (from the transceiver) otherwise.
-	 */
-	devctl = musb_readb(mregs, MUSB_DEVCTL);
-	dev_dbg(musb->controller, "poll devctl %02x (%s)\n", devctl,
-		usb_otg_state_string(musb->xceiv->otg->state));
-
-	spin_lock_irqsave(&musb->lock, flags);
-	switch (musb->xceiv->otg->state) {
-	case OTG_STATE_A_WAIT_VFALL:
-		/* Wait till VBUS falls below SessionEnd (~0.2V); the 1.3 RTL
-		 * seems to mis-handle session "start" otherwise (or in our
-		 * case "recover"), in routine "VBUS was valid by the time
-		 * VBUSERR got reported during enumeration" cases.
-		 */
-		if (devctl & MUSB_DEVCTL_VBUS) {
-			mod_timer(&musb->dev_timer, jiffies + POLL_SECONDS * HZ);
-			break;
-		}
-		musb->xceiv->otg->state = OTG_STATE_A_WAIT_VRISE;
-		musb_writel(musb->ctrl_base, DAVINCI_USB_INT_SET_REG,
-			MUSB_INTR_VBUSERROR << DAVINCI_USB_USBINT_SHIFT);
-		break;
-	case OTG_STATE_B_IDLE:
-		/*
-		 * There's no ID-changed IRQ, so we have no good way to tell
-		 * when to switch to the A-Default state machine (by setting
-		 * the DEVCTL.SESSION flag).
-		 *
-		 * Workaround:  whenever we're in B_IDLE, try setting the
-		 * session flag every few seconds.  If it works, ID was
-		 * grounded and we're now in the A-Default state machine.
-		 *
-		 * NOTE setting the session flag is _supposed_ to trigger
-		 * SRP, but clearly it doesn't.
-		 */
-		musb_writeb(mregs, MUSB_DEVCTL,
-				devctl | MUSB_DEVCTL_SESSION);
-		devctl = musb_readb(mregs, MUSB_DEVCTL);
-		if (devctl & MUSB_DEVCTL_BDEVICE)
-			mod_timer(&musb->dev_timer, jiffies + POLL_SECONDS * HZ);
-		else
-			musb->xceiv->otg->state = OTG_STATE_A_IDLE;
-		break;
-	default:
-		break;
-	}
-	spin_unlock_irqrestore(&musb->lock, flags);
-}
-
-static irqreturn_t davinci_musb_interrupt(int irq, void *__hci)
-{
-	unsigned long	flags;
-	irqreturn_t	retval = IRQ_NONE;
-	struct musb	*musb = __hci;
-	struct usb_otg	*otg = musb->xceiv->otg;
-	void __iomem	*tibase = musb->ctrl_base;
-	struct cppi	*cppi;
-	u32		tmp;
-
-	spin_lock_irqsave(&musb->lock, flags);
-
-	/* NOTE: DaVinci shadows the Mentor IRQs.  Don't manage them through
-	 * the Mentor registers (except for setup), use the TI ones and EOI.
-	 *
-	 * Docs describe irq "vector" registers associated with the CPPI and
-	 * USB EOI registers.  These hold a bitmask corresponding to the
-	 * current IRQ, not an irq handler address.  Would using those bits
-	 * resolve some of the races observed in this dispatch code??
-	 */
-
-	/* CPPI interrupts share the same IRQ line, but have their own
-	 * mask, state, "vector", and EOI registers.
-	 */
-	cppi = container_of(musb->dma_controller, struct cppi, controller);
-	if (is_cppi_enabled(musb) && musb->dma_controller && !cppi->irq)
-		retval = cppi_interrupt(irq, __hci);
-
-	/* ack and handle non-CPPI interrupts */
-	tmp = musb_readl(tibase, DAVINCI_USB_INT_SRC_MASKED_REG);
-	musb_writel(tibase, DAVINCI_USB_INT_SRC_CLR_REG, tmp);
-	dev_dbg(musb->controller, "IRQ %08x\n", tmp);
-
-	musb->int_rx = (tmp & DAVINCI_USB_RXINT_MASK)
-			>> DAVINCI_USB_RXINT_SHIFT;
-	musb->int_tx = (tmp & DAVINCI_USB_TXINT_MASK)
-			>> DAVINCI_USB_TXINT_SHIFT;
-	musb->int_usb = (tmp & DAVINCI_USB_USBINT_MASK)
-			>> DAVINCI_USB_USBINT_SHIFT;
-
-	/* DRVVBUS irqs are the only proxy we have (a very poor one!) for
-	 * DaVinci's missing ID change IRQ.  We need an ID change IRQ to
-	 * switch appropriately between halves of the OTG state machine.
-	 * Managing DEVCTL.SESSION per Mentor docs requires we know its
-	 * value, but DEVCTL.BDEVICE is invalid without DEVCTL.SESSION set.
-	 * Also, DRVVBUS pulses for SRP (but not at 5V) ...
-	 */
-	if (tmp & (DAVINCI_INTR_DRVVBUS << DAVINCI_USB_USBINT_SHIFT)) {
-		int	drvvbus = musb_readl(tibase, DAVINCI_USB_STAT_REG);
-		void __iomem *mregs = musb->mregs;
-		u8	devctl = musb_readb(mregs, MUSB_DEVCTL);
-		int	err = musb->int_usb & MUSB_INTR_VBUSERROR;
-
-		err = musb->int_usb & MUSB_INTR_VBUSERROR;
-		if (err) {
-			/* The Mentor core doesn't debounce VBUS as needed
-			 * to cope with device connect current spikes. This
-			 * means it's not uncommon for bus-powered devices
-			 * to get VBUS errors during enumeration.
-			 *
-			 * This is a workaround, but newer RTL from Mentor
-			 * seems to allow a better one: "re"starting sessions
-			 * without waiting (on EVM, a **long** time) for VBUS
-			 * to stop registering in devctl.
-			 */
-			musb->int_usb &= ~MUSB_INTR_VBUSERROR;
-			musb->xceiv->otg->state = OTG_STATE_A_WAIT_VFALL;
-			mod_timer(&musb->dev_timer, jiffies + POLL_SECONDS * HZ);
-			WARNING("VBUS error workaround (delay coming)\n");
-		} else if (drvvbus) {
-			MUSB_HST_MODE(musb);
-			musb->xceiv->otg->state = OTG_STATE_A_WAIT_VRISE;
-			portstate(musb->port1_status |= USB_PORT_STAT_POWER);
-			del_timer(&musb->dev_timer);
-		} else {
-			musb->is_active = 0;
-			MUSB_DEV_MODE(musb);
-			musb->xceiv->otg->state = OTG_STATE_B_IDLE;
-			portstate(musb->port1_status &= ~USB_PORT_STAT_POWER);
-		}
-
-		/* NOTE:  this must complete poweron within 100 msec
-		 * (OTG_TIME_A_WAIT_VRISE) but we don't check for that.
-		 */
-		davinci_musb_source_power(musb, drvvbus, 0);
-		dev_dbg(musb->controller, "VBUS %s (%s)%s, devctl %02x\n",
-				drvvbus ? "on" : "off",
-				usb_otg_state_string(musb->xceiv->otg->state),
-				err ? " ERROR" : "",
-				devctl);
-		retval = IRQ_HANDLED;
-	}
-
-	if (musb->int_tx || musb->int_rx || musb->int_usb)
-		retval |= musb_interrupt(musb);
-
-	/* irq stays asserted until EOI is written */
-	musb_writel(tibase, DAVINCI_USB_EOI_REG, 0);
-
-	/* poll for ID change */
-	if (musb->xceiv->otg->state == OTG_STATE_B_IDLE)
-		mod_timer(&musb->dev_timer, jiffies + POLL_SECONDS * HZ);
-
-	spin_unlock_irqrestore(&musb->lock, flags);
-
-	return retval;
-}
-
-static int davinci_musb_set_mode(struct musb *musb, u8 mode)
-{
-	/* EVM can't do this (right?) */
-	return -EIO;
-}
-
-static int davinci_musb_init(struct musb *musb)
-{
-	void __iomem	*tibase = musb->ctrl_base;
-	u32		revision;
-	int 		ret = -ENODEV;
-
-	musb->xceiv = usb_get_phy(USB_PHY_TYPE_USB2);
-	if (IS_ERR_OR_NULL(musb->xceiv)) {
-		ret = -EPROBE_DEFER;
-		goto unregister;
-	}
-
-	musb->mregs += DAVINCI_BASE_OFFSET;
-
-	/* returns zero if e.g. not clocked */
-	revision = musb_readl(tibase, DAVINCI_USB_VERSION_REG);
-	if (revision == 0)
-		goto fail;
-
-	timer_setup(&musb->dev_timer, otg_timer, 0);
-
-	davinci_musb_source_power(musb, 0, 1);
-
-	/* dm355 EVM swaps D+/D- for signal integrity, and
-	 * is clocked from the main 24 MHz crystal.
-	 */
-	if (machine_is_davinci_dm355_evm()) {
-		u32	phy_ctrl = __raw_readl(USB_PHY_CTRL);
-
-		phy_ctrl &= ~(3 << 9);
-		phy_ctrl |= USBPHY_DATAPOL;
-		__raw_writel(phy_ctrl, USB_PHY_CTRL);
-	}
-
-	/* On dm355, the default-A state machine needs DRVVBUS control.
-	 * If we won't be a host, there's no need to turn it on.
-	 */
-	if (cpu_is_davinci_dm355()) {
-		u32	deepsleep = __raw_readl(DM355_DEEPSLEEP);
-
-		deepsleep &= ~DRVVBUS_FORCE;
-		__raw_writel(deepsleep, DM355_DEEPSLEEP);
-	}
-
-	/* reset the controller */
-	musb_writel(tibase, DAVINCI_USB_CTRL_REG, 0x1);
-
-	/* start the on-chip PHY and its PLL */
-	phy_on();
-
-	msleep(5);
-
-	/* NOTE:  irqs are in mixed mode, not bypass to pure-musb */
-	pr_debug("DaVinci OTG revision %08x phy %03x control %02x\n",
-		revision, __raw_readl(USB_PHY_CTRL),
-		musb_readb(tibase, DAVINCI_USB_CTRL_REG));
-
-	musb->isr = davinci_musb_interrupt;
-	return 0;
-
-fail:
-	usb_put_phy(musb->xceiv);
-unregister:
-	usb_phy_generic_unregister();
-	return ret;
-}
-
-static int davinci_musb_exit(struct musb *musb)
-{
-	int	maxdelay = 30;
-	u8	devctl, warn = 0;
-
-	del_timer_sync(&musb->dev_timer);
-
-	/* force VBUS off */
-	if (cpu_is_davinci_dm355()) {
-		u32	deepsleep = __raw_readl(DM355_DEEPSLEEP);
-
-		deepsleep &= ~DRVVBUS_FORCE;
-		deepsleep |= DRVVBUS_OVERRIDE;
-		__raw_writel(deepsleep, DM355_DEEPSLEEP);
-	}
-
-	davinci_musb_source_power(musb, 0 /*off*/, 1);
-
-	/*
-	 * delay, to avoid problems with module reload.
-	 * if there's no peripheral connected, this can take a
-	 * long time to fall, especially on EVM with huge C133.
-	 */
-	do {
-		devctl = musb_readb(musb->mregs, MUSB_DEVCTL);
-		if (!(devctl & MUSB_DEVCTL_VBUS))
-			break;
-		if ((devctl & MUSB_DEVCTL_VBUS) != warn) {
-			warn = devctl & MUSB_DEVCTL_VBUS;
-			dev_dbg(musb->controller, "VBUS %d\n",
-				warn >> MUSB_DEVCTL_VBUS_SHIFT);
-		}
-		msleep(1000);
-		maxdelay--;
-	} while (maxdelay > 0);
-
-	/* in OTG mode, another host might be connected */
-	if (devctl & MUSB_DEVCTL_VBUS)
-		dev_dbg(musb->controller, "VBUS off timeout (devctl %02x)\n", devctl);
-
-	phy_off();
-
-	usb_put_phy(musb->xceiv);
-
-	return 0;
-}
-
-static const struct musb_platform_ops davinci_ops = {
-	.quirks		= MUSB_DMA_CPPI,
-	.init		= davinci_musb_init,
-	.exit		= davinci_musb_exit,
-
-#ifdef CONFIG_USB_TI_CPPI_DMA
-	.dma_init	= cppi_dma_controller_create,
-	.dma_exit	= cppi_dma_controller_destroy,
-#endif
-	.enable		= davinci_musb_enable,
-	.disable	= davinci_musb_disable,
-
-	.set_mode	= davinci_musb_set_mode,
-
-	.set_vbus	= davinci_musb_set_vbus,
-};
-
-static const struct platform_device_info davinci_dev_info = {
-	.name		= "musb-hdrc",
-	.id		= PLATFORM_DEVID_AUTO,
-	.dma_mask	= DMA_BIT_MASK(32),
-};
-
-static int davinci_probe(struct platform_device *pdev)
-{
-	struct resource			musb_resources[3];
-	struct musb_hdrc_platform_data	*pdata = dev_get_platdata(&pdev->dev);
-	struct platform_device		*musb;
-	struct davinci_glue		*glue;
-	struct platform_device_info	pinfo;
-	struct clk			*clk;
-
-	int				ret = -ENOMEM;
-
-	glue = devm_kzalloc(&pdev->dev, sizeof(*glue), GFP_KERNEL);
-	if (!glue)
-		goto err0;
-
-	clk = devm_clk_get(&pdev->dev, "usb");
-	if (IS_ERR(clk)) {
-		dev_err(&pdev->dev, "failed to get clock\n");
-		ret = PTR_ERR(clk);
-		goto err0;
-	}
-
-	ret = clk_enable(clk);
-	if (ret) {
-		dev_err(&pdev->dev, "failed to enable clock\n");
-		goto err0;
-	}
-
-	glue->dev			= &pdev->dev;
-	glue->clk			= clk;
-
-	pdata->platform_ops		= &davinci_ops;
-
-	glue->vbus = devm_gpiod_get_optional(&pdev->dev, NULL, GPIOD_OUT_LOW);
-	if (IS_ERR(glue->vbus)) {
-		ret = PTR_ERR(glue->vbus);
-		goto err0;
-	} else {
-		glue->vbus_state = -1;
-		INIT_WORK(&glue->vbus_work, evm_deferred_drvvbus);
-	}
-
-	usb_phy_generic_register();
-	platform_set_drvdata(pdev, glue);
-
-	memset(musb_resources, 0x00, sizeof(*musb_resources) *
-			ARRAY_SIZE(musb_resources));
-
-	musb_resources[0].name = pdev->resource[0].name;
-	musb_resources[0].start = pdev->resource[0].start;
-	musb_resources[0].end = pdev->resource[0].end;
-	musb_resources[0].flags = pdev->resource[0].flags;
-
-	musb_resources[1].name = pdev->resource[1].name;
-	musb_resources[1].start = pdev->resource[1].start;
-	musb_resources[1].end = pdev->resource[1].end;
-	musb_resources[1].flags = pdev->resource[1].flags;
-
-	/*
-	 * For DM6467 3 resources are passed. A placeholder for the 3rd
-	 * resource is always there, so it's safe to always copy it...
-	 */
-	musb_resources[2].name = pdev->resource[2].name;
-	musb_resources[2].start = pdev->resource[2].start;
-	musb_resources[2].end = pdev->resource[2].end;
-	musb_resources[2].flags = pdev->resource[2].flags;
-
-	pinfo = davinci_dev_info;
-	pinfo.parent = &pdev->dev;
-	pinfo.res = musb_resources;
-	pinfo.num_res = ARRAY_SIZE(musb_resources);
-	pinfo.data = pdata;
-	pinfo.size_data = sizeof(*pdata);
-
-	glue->musb = musb = platform_device_register_full(&pinfo);
-	if (IS_ERR(musb)) {
-		ret = PTR_ERR(musb);
-		dev_err(&pdev->dev, "failed to register musb device: %d\n", ret);
-		goto err1;
-	}
-
-	return 0;
-
-err1:
-	clk_disable(clk);
-
-err0:
-	return ret;
-}
-
-static int davinci_remove(struct platform_device *pdev)
-{
-	struct davinci_glue		*glue = platform_get_drvdata(pdev);
-
-	platform_device_unregister(glue->musb);
-	usb_phy_generic_unregister();
-	clk_disable(glue->clk);
-
-	return 0;
-}
-
-static struct platform_driver davinci_driver = {
-	.probe		= davinci_probe,
-	.remove		= davinci_remove,
-	.driver		= {
-		.name	= "musb-davinci",
-	},
-};
-
-MODULE_DESCRIPTION("DaVinci MUSB Glue Layer");
-MODULE_AUTHOR("Felipe Balbi <balbi@ti.com>");
-MODULE_LICENSE("GPL v2");
-module_platform_driver(davinci_driver);
diff --git a/drivers/usb/musb/davinci.h b/drivers/usb/musb/davinci.h
deleted file mode 100644
index c8e67d15b510..000000000000
--- a/drivers/usb/musb/davinci.h
+++ /dev/null
@@ -1,103 +0,0 @@ 
-/* SPDX-License-Identifier: GPL-2.0 */
-/*
- * Copyright (C) 2005-2006 by Texas Instruments
- */
-
-#ifndef __MUSB_HDRDF_H__
-#define __MUSB_HDRDF_H__
-
-/*
- * DaVinci-specific definitions
- */
-
-/* Integrated highspeed/otg PHY */
-#define USBPHY_CTL_PADDR	0x01c40034
-#define USBPHY_DATAPOL		BIT(11)	/* (dm355) switch D+/D- */
-#define USBPHY_PHYCLKGD		BIT(8)
-#define USBPHY_SESNDEN		BIT(7)	/* v(sess_end) comparator */
-#define USBPHY_VBDTCTEN		BIT(6)	/* v(bus) comparator */
-#define USBPHY_VBUSSENS		BIT(5)	/* (dm355,ro) is vbus > 0.5V */
-#define USBPHY_PHYPLLON		BIT(4)	/* override pll suspend */
-#define USBPHY_CLKO1SEL		BIT(3)
-#define USBPHY_OSCPDWN		BIT(2)
-#define USBPHY_OTGPDWN		BIT(1)
-#define USBPHY_PHYPDWN		BIT(0)
-
-#define DM355_DEEPSLEEP_PADDR	0x01c40048
-#define DRVVBUS_FORCE		BIT(2)
-#define DRVVBUS_OVERRIDE	BIT(1)
-
-/* For now include usb OTG module registers here */
-#define DAVINCI_USB_VERSION_REG		0x00
-#define DAVINCI_USB_CTRL_REG		0x04
-#define DAVINCI_USB_STAT_REG		0x08
-#define DAVINCI_RNDIS_REG		0x10
-#define DAVINCI_AUTOREQ_REG		0x14
-#define DAVINCI_USB_INT_SOURCE_REG	0x20
-#define DAVINCI_USB_INT_SET_REG		0x24
-#define DAVINCI_USB_INT_SRC_CLR_REG	0x28
-#define DAVINCI_USB_INT_MASK_REG	0x2c
-#define DAVINCI_USB_INT_MASK_SET_REG	0x30
-#define DAVINCI_USB_INT_MASK_CLR_REG	0x34
-#define DAVINCI_USB_INT_SRC_MASKED_REG	0x38
-#define DAVINCI_USB_EOI_REG		0x3c
-#define DAVINCI_USB_EOI_INTVEC		0x40
-
-/* BEGIN CPPI-generic (?) */
-
-/* CPPI related registers */
-#define DAVINCI_TXCPPI_CTRL_REG		0x80
-#define DAVINCI_TXCPPI_TEAR_REG		0x84
-#define DAVINCI_CPPI_EOI_REG		0x88
-#define DAVINCI_CPPI_INTVEC_REG		0x8c
-#define DAVINCI_TXCPPI_MASKED_REG	0x90
-#define DAVINCI_TXCPPI_RAW_REG		0x94
-#define DAVINCI_TXCPPI_INTENAB_REG	0x98
-#define DAVINCI_TXCPPI_INTCLR_REG	0x9c
-
-#define DAVINCI_RXCPPI_CTRL_REG		0xC0
-#define DAVINCI_RXCPPI_MASKED_REG	0xD0
-#define DAVINCI_RXCPPI_RAW_REG		0xD4
-#define DAVINCI_RXCPPI_INTENAB_REG	0xD8
-#define DAVINCI_RXCPPI_INTCLR_REG	0xDC
-
-#define DAVINCI_RXCPPI_BUFCNT0_REG	0xE0
-#define DAVINCI_RXCPPI_BUFCNT1_REG	0xE4
-#define DAVINCI_RXCPPI_BUFCNT2_REG	0xE8
-#define DAVINCI_RXCPPI_BUFCNT3_REG	0xEC
-
-/* CPPI state RAM entries */
-#define DAVINCI_CPPI_STATERAM_BASE_OFFSET   0x100
-
-#define DAVINCI_TXCPPI_STATERAM_OFFSET(chnum) \
-	(DAVINCI_CPPI_STATERAM_BASE_OFFSET +       ((chnum) * 0x40))
-#define DAVINCI_RXCPPI_STATERAM_OFFSET(chnum) \
-	(DAVINCI_CPPI_STATERAM_BASE_OFFSET + 0x20 + ((chnum) * 0x40))
-
-/* CPPI masks */
-#define DAVINCI_DMA_CTRL_ENABLE		1
-#define DAVINCI_DMA_CTRL_DISABLE	0
-
-#define DAVINCI_DMA_ALL_CHANNELS_ENABLE	0xF
-#define DAVINCI_DMA_ALL_CHANNELS_DISABLE 0xF
-
-/* END CPPI-generic (?) */
-
-#define DAVINCI_USB_TX_ENDPTS_MASK	0x1f		/* ep0 + 4 tx */
-#define DAVINCI_USB_RX_ENDPTS_MASK	0x1e		/* 4 rx */
-
-#define DAVINCI_USB_USBINT_SHIFT	16
-#define DAVINCI_USB_TXINT_SHIFT		0
-#define DAVINCI_USB_RXINT_SHIFT		8
-
-#define DAVINCI_INTR_DRVVBUS		0x0100
-
-#define DAVINCI_USB_USBINT_MASK		0x01ff0000	/* 8 Mentor, DRVVBUS */
-#define DAVINCI_USB_TXINT_MASK \
-	(DAVINCI_USB_TX_ENDPTS_MASK << DAVINCI_USB_TXINT_SHIFT)
-#define DAVINCI_USB_RXINT_MASK \
-	(DAVINCI_USB_RX_ENDPTS_MASK << DAVINCI_USB_RXINT_SHIFT)
-
-#define DAVINCI_BASE_OFFSET		0x400
-
-#endif	/* __MUSB_HDRDF_H__ */