arch/arm/mach-rpc/dma.c - third_party/kernel - Git at Google

 // SPDX-License-Identifier: GPL-2.0-only
 /*
  *  linux/arch/arm/mach-rpc/dma.c
  *
  *  Copyright (C) 1998 Russell King
  *
  *  DMA functions specific to RiscPC architecture
  */
 #include <linux/mman.h>
 #include <linux/init.h>
 #include <linux/interrupt.h>
 #include <linux/dma-mapping.h>
 #include <linux/io.h>

 #include <asm/page.h>
 #include <asm/dma.h>
 #include <asm/fiq.h>
 #include <asm/irq.h>
 #include <mach/hardware.h>
 #include <linux/uaccess.h>

 #include <asm/mach/dma.h>
 #include <asm/hardware/iomd.h>

 struct iomd_dma {
 	struct dma_struct	dma;
 	void __iomem		*base;		/* Controller base address */
 	int			irq;		/* Controller IRQ */
 	unsigned int		state;
 	dma_addr_t		cur_addr;
 	unsigned int		cur_len;
 	dma_addr_t		dma_addr;
 	unsigned int		dma_len;
 };

 #if 0
 typedef enum {
 	dma_size_8	= 1,
 	dma_size_16	= 2,
 	dma_size_32	= 4,
 	dma_size_128	= 16
 } dma_size_t;
 #endif

 #define TRANSFER_SIZE	2

 #define CURA	(0)
 #define ENDA	(IOMD_IO0ENDA - IOMD_IO0CURA)
 #define CURB	(IOMD_IO0CURB - IOMD_IO0CURA)
 #define ENDB	(IOMD_IO0ENDB - IOMD_IO0CURA)
 #define CR	(IOMD_IO0CR - IOMD_IO0CURA)
 #define ST	(IOMD_IO0ST - IOMD_IO0CURA)

 static void iomd_get_next_sg(struct iomd_dma *idma)
 {
 	unsigned long end, offset, flags = 0;

 	if (idma->dma.sg) {
 		idma->cur_addr = idma->dma_addr;
 		offset = idma->cur_addr & ~PAGE_MASK;

 		end = offset + idma->dma_len;

 		if (end > PAGE_SIZE)
 			end = PAGE_SIZE;

 		if (offset + TRANSFER_SIZE >= end)
 			flags |= DMA_END_L;

 		idma->cur_len = end - TRANSFER_SIZE;

 		idma->dma_len -= end - offset;
 		idma->dma_addr += end - offset;

 		if (idma->dma_len == 0) {
 			if (idma->dma.sgcount > 1) {
 				idma->dma.sg = sg_next(idma->dma.sg);
 				idma->dma_addr = idma->dma.sg->dma_address;
 				idma->dma_len = idma->dma.sg->length;
 				idma->dma.sgcount--;
 			} else {
 				idma->dma.sg = NULL;
 				flags |= DMA_END_S;
 			}
 		}
 	} else {
 		flags = DMA_END_S | DMA_END_L;
 		idma->cur_addr = 0;
 		idma->cur_len = 0;
 	}

 	idma->cur_len |= flags;
 }

 static irqreturn_t iomd_dma_handle(int irq, void *dev_id)
 {
 	struct iomd_dma *idma = dev_id;
 	void __iomem *base = idma->base;
 	unsigned int state = idma->state;
 	unsigned int status, cur, end;

 	do {
 		status = readb(base + ST);
 		if (!(status & DMA_ST_INT))
 			goto out;

 		if ((state ^ status) & DMA_ST_AB)
 			iomd_get_next_sg(idma);

 		// This efficiently implements state = OFL != AB ? AB : 0
 		state = ((status >> 2) ^ status) & DMA_ST_AB;
 		if (state) {
 			cur = CURA;
 			end = ENDA;
 		} else {
 			cur = CURB;
 			end = ENDB;
 		}
 		writel(idma->cur_addr, base + cur);
 		writel(idma->cur_len, base + end);

 		if (status & DMA_ST_OFL &&
 		    idma->cur_len == (DMA_END_S|DMA_END_L))
 			break;
 	} while (1);

 	state = ~DMA_ST_AB;
 	disable_irq_nosync(irq);
 out:
 	idma->state = state;
 	return IRQ_HANDLED;
 }

 static int iomd_request_dma(unsigned int chan, dma_t *dma)
 {
 	struct iomd_dma *idma = container_of(dma, struct iomd_dma, dma);

 	return request_irq(idma->irq, iomd_dma_handle,
 			   0, idma->dma.device_id, idma);
 }

 static void iomd_free_dma(unsigned int chan, dma_t *dma)
 {
 	struct iomd_dma *idma = container_of(dma, struct iomd_dma, dma);

 	free_irq(idma->irq, idma);
 }

 static struct device isa_dma_dev = {
 	.init_name		= "fallback device",
 	.coherent_dma_mask	= ~(dma_addr_t)0,
 	.dma_mask		= &isa_dma_dev.coherent_dma_mask,
 };

 static void iomd_enable_dma(unsigned int chan, dma_t *dma)
 {
 	struct iomd_dma *idma = container_of(dma, struct iomd_dma, dma);
 	void __iomem *base = idma->base;
 	unsigned int ctrl = TRANSFER_SIZE | DMA_CR_E;

 	if (idma->dma.invalid) {
 		idma->dma.invalid = 0;

 		/*
 		 * Cope with ISA-style drivers which expect cache
 		 * coherence.
 		 */
 		if (!idma->dma.sg) {
 			idma->dma.sg = &idma->dma.buf;
 			idma->dma.sgcount = 1;
 			idma->dma.buf.length = idma->dma.count;
 			idma->dma.buf.dma_address = dma_map_single(&isa_dma_dev,
 				idma->dma.addr, idma->dma.count,
 				idma->dma.dma_mode == DMA_MODE_READ ?
 				DMA_FROM_DEVICE : DMA_TO_DEVICE);
 		}

 		idma->dma_addr = idma->dma.sg->dma_address;
 		idma->dma_len = idma->dma.sg->length;

 		writeb(DMA_CR_C, base + CR);
 		idma->state = DMA_ST_AB;
 	}

 	if (idma->dma.dma_mode == DMA_MODE_READ)
 		ctrl |= DMA_CR_D;

 	writeb(ctrl, base + CR);
 	enable_irq(idma->irq);
 }

 static void iomd_disable_dma(unsigned int chan, dma_t *dma)
 {
 	struct iomd_dma *idma = container_of(dma, struct iomd_dma, dma);
 	void __iomem *base = idma->base;
 	unsigned long flags;

 	local_irq_save(flags);
 	if (idma->state != ~DMA_ST_AB)
 		disable_irq(idma->irq);
 	writeb(0, base + CR);
 	local_irq_restore(flags);
 }

 static int iomd_set_dma_speed(unsigned int chan, dma_t *dma, int cycle)
 {
 	int tcr, speed;

 	if (cycle < 188)
 		speed = 3;
 	else if (cycle <= 250)
 		speed = 2;
 	else if (cycle < 438)
 		speed = 1;
 	else
 		speed = 0;

 	tcr = iomd_readb(IOMD_DMATCR);
 	speed &= 3;

 	switch (chan) {
 	case DMA_0:
 		tcr = (tcr & ~0x03) | speed;
 		break;

 	case DMA_1:
 		tcr = (tcr & ~0x0c) | (speed << 2);
 		break;

 	case DMA_2:
 		tcr = (tcr & ~0x30) | (speed << 4);
 		break;

 	case DMA_3:
 		tcr = (tcr & ~0xc0) | (speed << 6);
 		break;

 	default:
 		break;
 	}

 	iomd_writeb(tcr, IOMD_DMATCR);

 	return speed;
 }

 static struct dma_ops iomd_dma_ops = {
 	.type		= "IOMD",
 	.request	= iomd_request_dma,
 	.free		= iomd_free_dma,
 	.enable		= iomd_enable_dma,
 	.disable	= iomd_disable_dma,
 	.setspeed	= iomd_set_dma_speed,
 };

 static struct fiq_handler fh = {
 	.name	= "floppydma"
 };

 struct floppy_dma {
 	struct dma_struct	dma;
 	unsigned int		fiq;
 };

 static void floppy_enable_dma(unsigned int chan, dma_t *dma)
 {
 	struct floppy_dma *fdma = container_of(dma, struct floppy_dma, dma);
 	void *fiqhandler_start;
 	unsigned int fiqhandler_length;
 	struct pt_regs regs;

 	if (fdma->dma.sg)
 		BUG();

 	if (fdma->dma.dma_mode == DMA_MODE_READ) {
 		extern unsigned char floppy_fiqin_start, floppy_fiqin_end;
 		fiqhandler_start = &floppy_fiqin_start;
 		fiqhandler_length = &floppy_fiqin_end - &floppy_fiqin_start;
 	} else {
 		extern unsigned char floppy_fiqout_start, floppy_fiqout_end;
 		fiqhandler_start = &floppy_fiqout_start;
 		fiqhandler_length = &floppy_fiqout_end - &floppy_fiqout_start;
 	}

 	regs.ARM_r9  = fdma->dma.count;
 	regs.ARM_r10 = (unsigned long)fdma->dma.addr;
 	regs.ARM_fp  = (unsigned long)FLOPPYDMA_BASE;

 	if (claim_fiq(&fh)) {
 		printk("floppydma: couldn't claim FIQ.\n");
 		return;
 	}

 	set_fiq_handler(fiqhandler_start, fiqhandler_length);
 	set_fiq_regs(&regs);
 	enable_fiq(fdma->fiq);
 }

 static void floppy_disable_dma(unsigned int chan, dma_t *dma)
 {
 	struct floppy_dma *fdma = container_of(dma, struct floppy_dma, dma);
 	disable_fiq(fdma->fiq);
 	release_fiq(&fh);
 }

 static int floppy_get_residue(unsigned int chan, dma_t *dma)
 {
 	struct pt_regs regs;
 	get_fiq_regs(&regs);
 	return regs.ARM_r9;
 }

 static struct dma_ops floppy_dma_ops = {
 	.type		= "FIQDMA",
 	.enable		= floppy_enable_dma,
 	.disable	= floppy_disable_dma,
 	.residue	= floppy_get_residue,
 };

 /*
  * This is virtual DMA - we don't need anything here.
  */
 static void sound_enable_disable_dma(unsigned int chan, dma_t *dma)
 {
 }

 static struct dma_ops sound_dma_ops = {
 	.type		= "VIRTUAL",
 	.enable		= sound_enable_disable_dma,
 	.disable	= sound_enable_disable_dma,
 };

 static struct iomd_dma iomd_dma[6];

 static struct floppy_dma floppy_dma = {
 	.dma		= {
 		.d_ops	= &floppy_dma_ops,
 	},
 	.fiq		= FIQ_FLOPPYDATA,
 };

 static dma_t sound_dma = {
 	.d_ops		= &sound_dma_ops,
 };

 static int __init rpc_dma_init(void)
 {
 	unsigned int i;
 	int ret;

 	iomd_writeb(0, IOMD_IO0CR);
 	iomd_writeb(0, IOMD_IO1CR);
 	iomd_writeb(0, IOMD_IO2CR);
 	iomd_writeb(0, IOMD_IO3CR);

 	iomd_writeb(0xa0, IOMD_DMATCR);

 	/*
 	 * Setup DMA channels 2,3 to be for podules
 	 * and channels 0,1 for internal devices
 	 */
 	iomd_writeb(DMA_EXT_IO3|DMA_EXT_IO2, IOMD_DMAEXT);

 	iomd_dma[DMA_0].base	= IOMD_BASE + IOMD_IO0CURA;
 	iomd_dma[DMA_0].irq	= IRQ_DMA0;
 	iomd_dma[DMA_1].base	= IOMD_BASE + IOMD_IO1CURA;
 	iomd_dma[DMA_1].irq	= IRQ_DMA1;
 	iomd_dma[DMA_2].base	= IOMD_BASE + IOMD_IO2CURA;
 	iomd_dma[DMA_2].irq	= IRQ_DMA2;
 	iomd_dma[DMA_3].base	= IOMD_BASE + IOMD_IO3CURA;
 	iomd_dma[DMA_3].irq	= IRQ_DMA3;
 	iomd_dma[DMA_S0].base	= IOMD_BASE + IOMD_SD0CURA;
 	iomd_dma[DMA_S0].irq	= IRQ_DMAS0;
 	iomd_dma[DMA_S1].base	= IOMD_BASE + IOMD_SD1CURA;
 	iomd_dma[DMA_S1].irq	= IRQ_DMAS1;

 	for (i = DMA_0; i <= DMA_S1; i++) {
 		iomd_dma[i].dma.d_ops = &iomd_dma_ops;

 		ret = isa_dma_add(i, &iomd_dma[i].dma);
 		if (ret)
 			printk("IOMDDMA%u: unable to register: %d\n", i, ret);
 	}

 	ret = isa_dma_add(DMA_VIRTUAL_FLOPPY, &floppy_dma.dma);
 	if (ret)
 		printk("IOMDFLOPPY: unable to register: %d\n", ret);
 	ret = isa_dma_add(DMA_VIRTUAL_SOUND, &sound_dma);
 	if (ret)
 		printk("IOMDSOUND: unable to register: %d\n", ret);
 	return 0;
 }
 core_initcall(rpc_dma_init);
	// SPDX-License-Identifier: GPL-2.0-only
	/*
	* linux/arch/arm/mach-rpc/dma.c
	*
	* Copyright (C) 1998 Russell King
	*
	* DMA functions specific to RiscPC architecture
	*/
	#include <linux/mman.h>
	#include <linux/init.h>
	#include <linux/interrupt.h>
	#include <linux/dma-mapping.h>
	#include <linux/io.h>

	#include <asm/page.h>
	#include <asm/dma.h>
	#include <asm/fiq.h>
	#include <asm/irq.h>
	#include <mach/hardware.h>
	#include <linux/uaccess.h>

	#include <asm/mach/dma.h>
	#include <asm/hardware/iomd.h>

	struct iomd_dma {
	struct dma_struct dma;
	void __iomem base; / Controller base address */
	int irq; /* Controller IRQ */
	unsigned int state;
	dma_addr_t cur_addr;
	unsigned int cur_len;
	dma_addr_t dma_addr;
	unsigned int dma_len;
	};

	#if 0
	typedef enum {
	dma_size_8 = 1,
	dma_size_16 = 2,
	dma_size_32 = 4,
	dma_size_128 = 16
	} dma_size_t;
	#endif

	#define TRANSFER_SIZE 2

	#define CURA (0)
	#define ENDA (IOMD_IO0ENDA - IOMD_IO0CURA)
	#define CURB (IOMD_IO0CURB - IOMD_IO0CURA)
	#define ENDB (IOMD_IO0ENDB - IOMD_IO0CURA)
	#define CR (IOMD_IO0CR - IOMD_IO0CURA)
	#define ST (IOMD_IO0ST - IOMD_IO0CURA)

	static void iomd_get_next_sg(struct iomd_dma *idma)
	{
	unsigned long end, offset, flags = 0;

	if (idma->dma.sg) {
	idma->cur_addr = idma->dma_addr;
	offset = idma->cur_addr & ~PAGE_MASK;

	end = offset + idma->dma_len;

	if (end > PAGE_SIZE)
	end = PAGE_SIZE;

	if (offset + TRANSFER_SIZE >= end)
	flags \|= DMA_END_L;

	idma->cur_len = end - TRANSFER_SIZE;

	idma->dma_len -= end - offset;
	idma->dma_addr += end - offset;

	if (idma->dma_len == 0) {
	if (idma->dma.sgcount > 1) {
	idma->dma.sg = sg_next(idma->dma.sg);
	idma->dma_addr = idma->dma.sg->dma_address;
	idma->dma_len = idma->dma.sg->length;
	idma->dma.sgcount--;
	} else {
	idma->dma.sg = NULL;
	flags \|= DMA_END_S;
	}
	}
	} else {
	flags = DMA_END_S \| DMA_END_L;
	idma->cur_addr = 0;
	idma->cur_len = 0;
	}

	idma->cur_len \|= flags;
	}

	static irqreturn_t iomd_dma_handle(int irq, void *dev_id)
	{
	struct iomd_dma *idma = dev_id;
	void __iomem *base = idma->base;
	unsigned int state = idma->state;
	unsigned int status, cur, end;

	do {
	status = readb(base + ST);
	if (!(status & DMA_ST_INT))
	goto out;

	if ((state ^ status) & DMA_ST_AB)
	iomd_get_next_sg(idma);

	// This efficiently implements state = OFL != AB ? AB : 0
	state = ((status >> 2) ^ status) & DMA_ST_AB;
	if (state) {
	cur = CURA;
	end = ENDA;
	} else {
	cur = CURB;
	end = ENDB;
	}
	writel(idma->cur_addr, base + cur);
	writel(idma->cur_len, base + end);

	if (status & DMA_ST_OFL &&
	idma->cur_len == (DMA_END_S\|DMA_END_L))
	break;
	} while (1);

	state = ~DMA_ST_AB;
	disable_irq_nosync(irq);
	out:
	idma->state = state;
	return IRQ_HANDLED;
	}

	static int iomd_request_dma(unsigned int chan, dma_t *dma)
	{
	struct iomd_dma *idma = container_of(dma, struct iomd_dma, dma);

	return request_irq(idma->irq, iomd_dma_handle,
	0, idma->dma.device_id, idma);
	}

	static void iomd_free_dma(unsigned int chan, dma_t *dma)
	{
	struct iomd_dma *idma = container_of(dma, struct iomd_dma, dma);

	free_irq(idma->irq, idma);
	}

	static struct device isa_dma_dev = {
	.init_name = "fallback device",
	.coherent_dma_mask = ~(dma_addr_t)0,
	.dma_mask = &isa_dma_dev.coherent_dma_mask,
	};

	static void iomd_enable_dma(unsigned int chan, dma_t *dma)
	{
	struct iomd_dma *idma = container_of(dma, struct iomd_dma, dma);
	void __iomem *base = idma->base;
	unsigned int ctrl = TRANSFER_SIZE \| DMA_CR_E;

	if (idma->dma.invalid) {
	idma->dma.invalid = 0;

	/*
	* Cope with ISA-style drivers which expect cache
	* coherence.
	*/
	if (!idma->dma.sg) {
	idma->dma.sg = &idma->dma.buf;
	idma->dma.sgcount = 1;
	idma->dma.buf.length = idma->dma.count;
	idma->dma.buf.dma_address = dma_map_single(&isa_dma_dev,
	idma->dma.addr, idma->dma.count,
	idma->dma.dma_mode == DMA_MODE_READ ?
	DMA_FROM_DEVICE : DMA_TO_DEVICE);
	}

	idma->dma_addr = idma->dma.sg->dma_address;
	idma->dma_len = idma->dma.sg->length;

	writeb(DMA_CR_C, base + CR);
	idma->state = DMA_ST_AB;
	}

	if (idma->dma.dma_mode == DMA_MODE_READ)
	ctrl \|= DMA_CR_D;

	writeb(ctrl, base + CR);
	enable_irq(idma->irq);
	}

	static void iomd_disable_dma(unsigned int chan, dma_t *dma)
	{
	struct iomd_dma *idma = container_of(dma, struct iomd_dma, dma);
	void __iomem *base = idma->base;
	unsigned long flags;

	local_irq_save(flags);
	if (idma->state != ~DMA_ST_AB)
	disable_irq(idma->irq);
	writeb(0, base + CR);
	local_irq_restore(flags);
	}

	static int iomd_set_dma_speed(unsigned int chan, dma_t *dma, int cycle)
	{
	int tcr, speed;

	if (cycle < 188)
	speed = 3;
	else if (cycle <= 250)
	speed = 2;
	else if (cycle < 438)
	speed = 1;
	else
	speed = 0;

	tcr = iomd_readb(IOMD_DMATCR);
	speed &= 3;

	switch (chan) {
	case DMA_0:
	tcr = (tcr & ~0x03) \| speed;
	break;

	case DMA_1:
	tcr = (tcr & ~0x0c) \| (speed << 2);
	break;

	case DMA_2:
	tcr = (tcr & ~0x30) \| (speed << 4);
	break;

	case DMA_3:
	tcr = (tcr & ~0xc0) \| (speed << 6);
	break;

	default:
	break;
	}

	iomd_writeb(tcr, IOMD_DMATCR);

	return speed;
	}

	static struct dma_ops iomd_dma_ops = {
	.type = "IOMD",
	.request = iomd_request_dma,
	.free = iomd_free_dma,
	.enable = iomd_enable_dma,
	.disable = iomd_disable_dma,
	.setspeed = iomd_set_dma_speed,
	};

	static struct fiq_handler fh = {
	.name = "floppydma"
	};

	struct floppy_dma {
	struct dma_struct dma;
	unsigned int fiq;
	};

	static void floppy_enable_dma(unsigned int chan, dma_t *dma)
	{
	struct floppy_dma *fdma = container_of(dma, struct floppy_dma, dma);
	void *fiqhandler_start;
	unsigned int fiqhandler_length;
	struct pt_regs regs;

	if (fdma->dma.sg)
	BUG();

	if (fdma->dma.dma_mode == DMA_MODE_READ) {
	extern unsigned char floppy_fiqin_start, floppy_fiqin_end;
	fiqhandler_start = &floppy_fiqin_start;
	fiqhandler_length = &floppy_fiqin_end - &floppy_fiqin_start;
	} else {
	extern unsigned char floppy_fiqout_start, floppy_fiqout_end;
	fiqhandler_start = &floppy_fiqout_start;
	fiqhandler_length = &floppy_fiqout_end - &floppy_fiqout_start;
	}

	regs.ARM_r9 = fdma->dma.count;
	regs.ARM_r10 = (unsigned long)fdma->dma.addr;
	regs.ARM_fp = (unsigned long)FLOPPYDMA_BASE;

	if (claim_fiq(&fh)) {
	printk("floppydma: couldn't claim FIQ.\n");
	return;
	}

	set_fiq_handler(fiqhandler_start, fiqhandler_length);
	set_fiq_regs(&regs);
	enable_fiq(fdma->fiq);
	}

	static void floppy_disable_dma(unsigned int chan, dma_t *dma)
	{
	struct floppy_dma *fdma = container_of(dma, struct floppy_dma, dma);
	disable_fiq(fdma->fiq);
	release_fiq(&fh);
	}

	static int floppy_get_residue(unsigned int chan, dma_t *dma)
	{
	struct pt_regs regs;
	get_fiq_regs(&regs);
	return regs.ARM_r9;
	}

	static struct dma_ops floppy_dma_ops = {
	.type = "FIQDMA",
	.enable = floppy_enable_dma,
	.disable = floppy_disable_dma,
	.residue = floppy_get_residue,
	};

	/*
	* This is virtual DMA - we don't need anything here.
	*/
	static void sound_enable_disable_dma(unsigned int chan, dma_t *dma)
	{
	}

	static struct dma_ops sound_dma_ops = {
	.type = "VIRTUAL",
	.enable = sound_enable_disable_dma,
	.disable = sound_enable_disable_dma,
	};

	static struct iomd_dma iomd_dma[6];

	static struct floppy_dma floppy_dma = {
	.dma = {
	.d_ops = &floppy_dma_ops,
	},
	.fiq = FIQ_FLOPPYDATA,
	};

	static dma_t sound_dma = {
	.d_ops = &sound_dma_ops,
	};

	static int __init rpc_dma_init(void)
	{
	unsigned int i;
	int ret;

	iomd_writeb(0, IOMD_IO0CR);
	iomd_writeb(0, IOMD_IO1CR);
	iomd_writeb(0, IOMD_IO2CR);
	iomd_writeb(0, IOMD_IO3CR);

	iomd_writeb(0xa0, IOMD_DMATCR);

	/*
	* Setup DMA channels 2,3 to be for podules
	* and channels 0,1 for internal devices
	*/
	iomd_writeb(DMA_EXT_IO3\|DMA_EXT_IO2, IOMD_DMAEXT);

	iomd_dma[DMA_0].base = IOMD_BASE + IOMD_IO0CURA;
	iomd_dma[DMA_0].irq = IRQ_DMA0;
	iomd_dma[DMA_1].base = IOMD_BASE + IOMD_IO1CURA;
	iomd_dma[DMA_1].irq = IRQ_DMA1;
	iomd_dma[DMA_2].base = IOMD_BASE + IOMD_IO2CURA;
	iomd_dma[DMA_2].irq = IRQ_DMA2;
	iomd_dma[DMA_3].base = IOMD_BASE + IOMD_IO3CURA;
	iomd_dma[DMA_3].irq = IRQ_DMA3;
	iomd_dma[DMA_S0].base = IOMD_BASE + IOMD_SD0CURA;
	iomd_dma[DMA_S0].irq = IRQ_DMAS0;
	iomd_dma[DMA_S1].base = IOMD_BASE + IOMD_SD1CURA;
	iomd_dma[DMA_S1].irq = IRQ_DMAS1;

	for (i = DMA_0; i <= DMA_S1; i++) {
	iomd_dma[i].dma.d_ops = &iomd_dma_ops;

	ret = isa_dma_add(i, &iomd_dma[i].dma);
	if (ret)
	printk("IOMDDMA%u: unable to register: %d\n", i, ret);
	}

	ret = isa_dma_add(DMA_VIRTUAL_FLOPPY, &floppy_dma.dma);
	if (ret)
	printk("IOMDFLOPPY: unable to register: %d\n", ret);
	ret = isa_dma_add(DMA_VIRTUAL_SOUND, &sound_dma);
	if (ret)
	printk("IOMDSOUND: unable to register: %d\n", ret);
	return 0;
	}
	core_initcall(rpc_dma_init);