[mirror_ubuntu-artful-kernel.git] / drivers / scsi / mac_esp.c

/* mac_esp.c: ESP front-end for Macintosh Quadra systems.
 *
 * Adapted from jazz_esp.c and the old mac_esp.c.
 *
 * The pseudo DMA algorithm is based on the one used in NetBSD.
 * See sys/arch/mac68k/obio/esp.c for some background information.
 *
 * Copyright (C) 2007-2008 Finn Thain
 */

#include <linux/kernel.h>
#include <linux/types.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/platform_device.h>
#include <linux/dma-mapping.h>
#include <linux/scatterlist.h>
#include <linux/delay.h>
#include <linux/io.h>
#include <linux/nubus.h>
#include <linux/slab.h>

#include <asm/irq.h>
#include <asm/dma.h>
#include <asm/macints.h>
#include <asm/macintosh.h>
#include <asm/mac_via.h>

#include <scsi/scsi_host.h>

#include "esp_scsi.h"

#define DRV_MODULE_NAME     "mac_esp"
#define PFX                 DRV_MODULE_NAME ": "
#define DRV_VERSION         "1.000"
#define DRV_MODULE_RELDATE  "Sept 15, 2007"

#define MAC_ESP_IO_BASE          0x50F00000
#define MAC_ESP_REGS_QUADRA      (MAC_ESP_IO_BASE + 0x10000)
#define MAC_ESP_REGS_QUADRA2     (MAC_ESP_IO_BASE + 0xF000)
#define MAC_ESP_REGS_QUADRA3     (MAC_ESP_IO_BASE + 0x18000)
#define MAC_ESP_REGS_SPACING     0x402
#define MAC_ESP_PDMA_REG         0xF9800024
#define MAC_ESP_PDMA_REG_SPACING 0x4
#define MAC_ESP_PDMA_IO_OFFSET   0x100

#define esp_read8(REG)		mac_esp_read8(esp, REG)
#define esp_write8(VAL, REG)	mac_esp_write8(esp, VAL, REG)

struct mac_esp_priv {
	struct esp *esp;
	void __iomem *pdma_regs;
	void __iomem *pdma_io;
	int error;
};
static struct esp *esp_chips[2];
static DEFINE_SPINLOCK(esp_chips_lock);

#define MAC_ESP_GET_PRIV(esp) ((struct mac_esp_priv *) \
			       platform_get_drvdata((struct platform_device *) \
						    (esp->dev)))

static inline void mac_esp_write8(struct esp *esp, u8 val, unsigned long reg)
{
	nubus_writeb(val, esp->regs + reg * 16);
}

static inline u8 mac_esp_read8(struct esp *esp, unsigned long reg)
{
	return nubus_readb(esp->regs + reg * 16);
}

/* For pseudo DMA and PIO we need the virtual address
 * so this address mapping is the identity mapping.
 */

static dma_addr_t mac_esp_map_single(struct esp *esp, void *buf,
				     size_t sz, int dir)
{
	return (dma_addr_t)buf;
}

static int mac_esp_map_sg(struct esp *esp, struct scatterlist *sg,
			  int num_sg, int dir)
{
	int i;

	for (i = 0; i < num_sg; i++)
		sg[i].dma_address = (u32)sg_virt(&sg[i]);
	return num_sg;
}

static void mac_esp_unmap_single(struct esp *esp, dma_addr_t addr,
				 size_t sz, int dir)
{
	/* Nothing to do. */
}

static void mac_esp_unmap_sg(struct esp *esp, struct scatterlist *sg,
			     int num_sg, int dir)
{
	/* Nothing to do. */
}

static void mac_esp_reset_dma(struct esp *esp)
{
	/* Nothing to do. */
}

static void mac_esp_dma_drain(struct esp *esp)
{
	/* Nothing to do. */
}

static void mac_esp_dma_invalidate(struct esp *esp)
{
	/* Nothing to do. */
}

static int mac_esp_dma_error(struct esp *esp)
{
	return MAC_ESP_GET_PRIV(esp)->error;
}

static inline int mac_esp_wait_for_empty_fifo(struct esp *esp)
{
	struct mac_esp_priv *mep = MAC_ESP_GET_PRIV(esp);
	int i = 500000;

	do {
		if (!(esp_read8(ESP_FFLAGS) & ESP_FF_FBYTES))
			return 0;

		if (esp_read8(ESP_STATUS) & ESP_STAT_INTR)
			return 1;

		udelay(2);
	} while (--i);

	printk(KERN_ERR PFX "FIFO is not empty (sreg %02x)\n",
	       esp_read8(ESP_STATUS));
	mep->error = 1;
	return 1;
}

static inline int mac_esp_wait_for_dreq(struct esp *esp)
{
	struct mac_esp_priv *mep = MAC_ESP_GET_PRIV(esp);
	int i = 500000;

	do {
		if (mep->pdma_regs == NULL) {
			if (via2_scsi_drq_pending())
				return 0;
		} else {
			if (nubus_readl(mep->pdma_regs) & 0x200)
				return 0;
		}

		if (esp_read8(ESP_STATUS) & ESP_STAT_INTR)
			return 1;

		udelay(2);
	} while (--i);

	printk(KERN_ERR PFX "PDMA timeout (sreg %02x)\n",
	       esp_read8(ESP_STATUS));
	mep->error = 1;
	return 1;
}

#define MAC_ESP_PDMA_LOOP(operands) \
	asm volatile ( \
	     "       tstw %1                   \n" \
	     "       jbeq 20f                  \n" \
	     "1:     movew " operands "        \n" \
	     "2:     movew " operands "        \n" \
	     "3:     movew " operands "        \n" \
	     "4:     movew " operands "        \n" \
	     "5:     movew " operands "        \n" \
	     "6:     movew " operands "        \n" \
	     "7:     movew " operands "        \n" \
	     "8:     movew " operands "        \n" \
	     "9:     movew " operands "        \n" \
	     "10:    movew " operands "        \n" \
	     "11:    movew " operands "        \n" \
	     "12:    movew " operands "        \n" \
	     "13:    movew " operands "        \n" \
	     "14:    movew " operands "        \n" \
	     "15:    movew " operands "        \n" \
	     "16:    movew " operands "        \n" \
	     "       subqw #1,%1               \n" \
	     "       jbne 1b                   \n" \
	     "20:    tstw %2                   \n" \
	     "       jbeq 30f                  \n" \
	     "21:    movew " operands "        \n" \
	     "       subqw #1,%2               \n" \
	     "       jbne 21b                  \n" \
	     "30:    tstw %3                   \n" \
	     "       jbeq 40f                  \n" \
	     "31:    moveb " operands "        \n" \
	     "32:    nop                       \n" \
	     "40:                              \n" \
	     "                                 \n" \
	     "       .section __ex_table,\"a\" \n" \
	     "       .align  4                 \n" \
	     "       .long   1b,40b            \n" \
	     "       .long   2b,40b            \n" \
	     "       .long   3b,40b            \n" \
	     "       .long   4b,40b            \n" \
	     "       .long   5b,40b            \n" \
	     "       .long   6b,40b            \n" \
	     "       .long   7b,40b            \n" \
	     "       .long   8b,40b            \n" \
	     "       .long   9b,40b            \n" \
	     "       .long  10b,40b            \n" \
	     "       .long  11b,40b            \n" \
	     "       .long  12b,40b            \n" \
	     "       .long  13b,40b            \n" \
	     "       .long  14b,40b            \n" \
	     "       .long  15b,40b            \n" \
	     "       .long  16b,40b            \n" \
	     "       .long  21b,40b            \n" \
	     "       .long  31b,40b            \n" \
	     "       .long  32b,40b            \n" \
	     "       .previous                 \n" \
	     : "+a" (addr), "+r" (count32), "+r" (count2) \
	     : "g" (count1), "a" (mep->pdma_io))

static void mac_esp_send_pdma_cmd(struct esp *esp, u32 addr, u32 esp_count,
				  u32 dma_count, int write, u8 cmd)
{
	struct mac_esp_priv *mep = MAC_ESP_GET_PRIV(esp);

	mep->error = 0;

	if (!write)
		scsi_esp_cmd(esp, ESP_CMD_FLUSH);

	esp_write8((esp_count >> 0) & 0xFF, ESP_TCLOW);
	esp_write8((esp_count >> 8) & 0xFF, ESP_TCMED);

	scsi_esp_cmd(esp, cmd);

	do {
		unsigned int count32 = esp_count >> 5;
		unsigned int count2 = (esp_count & 0x1F) >> 1;
		unsigned int count1 = esp_count & 1;
		unsigned int start_addr = addr;

		if (mac_esp_wait_for_dreq(esp))
			break;

		if (write) {
			MAC_ESP_PDMA_LOOP("%4@,%0@+");

			esp_count -= addr - start_addr;
		} else {
			unsigned int n;

			MAC_ESP_PDMA_LOOP("%0@+,%4@");

			if (mac_esp_wait_for_empty_fifo(esp))
				break;

			n = (esp_read8(ESP_TCMED) << 8) + esp_read8(ESP_TCLOW);
			addr = start_addr + esp_count - n;
			esp_count = n;
		}
	} while (esp_count);
}

/*
 * Programmed IO routines follow.
 */

static inline unsigned int mac_esp_wait_for_fifo(struct esp *esp)
{
	int i = 500000;

	do {
		unsigned int fbytes = esp_read8(ESP_FFLAGS) & ESP_FF_FBYTES;

		if (fbytes)
			return fbytes;

		udelay(2);
	} while (--i);

	printk(KERN_ERR PFX "FIFO is empty (sreg %02x)\n",
	       esp_read8(ESP_STATUS));
	return 0;
}

static inline int mac_esp_wait_for_intr(struct esp *esp)
{
	struct mac_esp_priv *mep = MAC_ESP_GET_PRIV(esp);
	int i = 500000;

	do {
		esp->sreg = esp_read8(ESP_STATUS);
		if (esp->sreg & ESP_STAT_INTR)
			return 0;

		udelay(2);
	} while (--i);

	printk(KERN_ERR PFX "IRQ timeout (sreg %02x)\n", esp->sreg);
	mep->error = 1;
	return 1;
}

#define MAC_ESP_PIO_LOOP(operands, reg1) \
	asm volatile ( \
	     "1:     moveb " operands " \n" \
	     "       subqw #1,%1        \n" \
	     "       jbne 1b            \n" \
	     : "+a" (addr), "+r" (reg1) \
	     : "a" (fifo))

#define MAC_ESP_PIO_FILL(operands, reg1) \
	asm volatile ( \
	     "       moveb " operands " \n" \
	     "       moveb " operands " \n" \
	     "       moveb " operands " \n" \
	     "       moveb " operands " \n" \
	     "       moveb " operands " \n" \
	     "       moveb " operands " \n" \
	     "       moveb " operands " \n" \
	     "       moveb " operands " \n" \
	     "       moveb " operands " \n" \
	     "       moveb " operands " \n" \
	     "       moveb " operands " \n" \
	     "       moveb " operands " \n" \
	     "       moveb " operands " \n" \
	     "       moveb " operands " \n" \
	     "       moveb " operands " \n" \
	     "       moveb " operands " \n" \
	     "       subqw #8,%1        \n" \
	     "       subqw #8,%1        \n" \
	     : "+a" (addr), "+r" (reg1) \
	     : "a" (fifo))

#define MAC_ESP_FIFO_SIZE 16

static void mac_esp_send_pio_cmd(struct esp *esp, u32 addr, u32 esp_count,
				 u32 dma_count, int write, u8 cmd)
{
	struct mac_esp_priv *mep = MAC_ESP_GET_PRIV(esp);
	u8 *fifo = esp->regs + ESP_FDATA * 16;

	cmd &= ~ESP_CMD_DMA;
	mep->error = 0;

	if (write) {
		scsi_esp_cmd(esp, cmd);

		while (1) {
			unsigned int n;

			n = mac_esp_wait_for_fifo(esp);
			if (!n)
				break;

			if (n > esp_count)
				n = esp_count;
			esp_count -= n;

			MAC_ESP_PIO_LOOP("%2@,%0@+", n);

			if (!esp_count)
				break;

			if (mac_esp_wait_for_intr(esp))
				break;

			if (((esp->sreg & ESP_STAT_PMASK) != ESP_DIP) &&
			    ((esp->sreg & ESP_STAT_PMASK) != ESP_MIP))
				break;

			esp->ireg = esp_read8(ESP_INTRPT);
			if ((esp->ireg & (ESP_INTR_DC | ESP_INTR_BSERV)) !=
			    ESP_INTR_BSERV)
				break;

			scsi_esp_cmd(esp, ESP_CMD_TI);
		}
	} else {
		scsi_esp_cmd(esp, ESP_CMD_FLUSH);

		if (esp_count >= MAC_ESP_FIFO_SIZE)
			MAC_ESP_PIO_FILL("%0@+,%2@", esp_count);
		else
			MAC_ESP_PIO_LOOP("%0@+,%2@", esp_count);

		scsi_esp_cmd(esp, cmd);

		while (esp_count) {
			unsigned int n;

			if (mac_esp_wait_for_intr(esp))
				break;

			if (((esp->sreg & ESP_STAT_PMASK) != ESP_DOP) &&
			    ((esp->sreg & ESP_STAT_PMASK) != ESP_MOP))
				break;

			esp->ireg = esp_read8(ESP_INTRPT);
			if ((esp->ireg & (ESP_INTR_DC | ESP_INTR_BSERV)) !=
			    ESP_INTR_BSERV)
				break;

			n = MAC_ESP_FIFO_SIZE -
			    (esp_read8(ESP_FFLAGS) & ESP_FF_FBYTES);
			if (n > esp_count)
				n = esp_count;

			if (n == MAC_ESP_FIFO_SIZE) {
				MAC_ESP_PIO_FILL("%0@+,%2@", esp_count);
			} else {
				esp_count -= n;
				MAC_ESP_PIO_LOOP("%0@+,%2@", n);
			}

			scsi_esp_cmd(esp, ESP_CMD_TI);
		}
	}
}

static int mac_esp_irq_pending(struct esp *esp)
{
	if (esp_read8(ESP_STATUS) & ESP_STAT_INTR)
		return 1;
	return 0;
}

static u32 mac_esp_dma_length_limit(struct esp *esp, u32 dma_addr, u32 dma_len)
{
	return dma_len > 0xFFFF ? 0xFFFF : dma_len;
}

static irqreturn_t mac_scsi_esp_intr(int irq, void *dev_id)
{
	int got_intr;

	/*
	 * This is an edge triggered IRQ, so we have to be careful to
	 * avoid missing a transition when it is shared by two ESP devices.
	 */

	do {
		got_intr = 0;
		if (esp_chips[0] &&
		    (mac_esp_read8(esp_chips[0], ESP_STATUS) & ESP_STAT_INTR)) {
			(void)scsi_esp_intr(irq, esp_chips[0]);
			got_intr = 1;
		}
		if (esp_chips[1] &&
		    (mac_esp_read8(esp_chips[1], ESP_STATUS) & ESP_STAT_INTR)) {
			(void)scsi_esp_intr(irq, esp_chips[1]);
			got_intr = 1;
		}
	} while (got_intr);

	return IRQ_HANDLED;
}

static struct esp_driver_ops mac_esp_ops = {
	.esp_write8       = mac_esp_write8,
	.esp_read8        = mac_esp_read8,
	.map_single       = mac_esp_map_single,
	.map_sg           = mac_esp_map_sg,
	.unmap_single     = mac_esp_unmap_single,
	.unmap_sg         = mac_esp_unmap_sg,
	.irq_pending      = mac_esp_irq_pending,
	.dma_length_limit = mac_esp_dma_length_limit,
	.reset_dma        = mac_esp_reset_dma,
	.dma_drain        = mac_esp_dma_drain,
	.dma_invalidate   = mac_esp_dma_invalidate,
	.send_dma_cmd     = mac_esp_send_pdma_cmd,
	.dma_error        = mac_esp_dma_error,
};

static int esp_mac_probe(struct platform_device *dev)
{
	struct scsi_host_template *tpnt = &scsi_esp_template;
	struct Scsi_Host *host;
	struct esp *esp;
	int err;
	struct mac_esp_priv *mep;

	if (!MACH_IS_MAC)
		return -ENODEV;

	if (dev->id > 1)
		return -ENODEV;

	host = scsi_host_alloc(tpnt, sizeof(struct esp));

	err = -ENOMEM;
	if (!host)
		goto fail;

	host->max_id = 8;
	host->use_clustering = DISABLE_CLUSTERING;
	esp = shost_priv(host);

	esp->host = host;
	esp->dev = dev;

	esp->command_block = kzalloc(16, GFP_KERNEL);
	if (!esp->command_block)
		goto fail_unlink;
	esp->command_block_dma = (dma_addr_t)esp->command_block;

	esp->scsi_id = 7;
	host->this_id = esp->scsi_id;
	esp->scsi_id_mask = 1 << esp->scsi_id;

	mep = kzalloc(sizeof(struct mac_esp_priv), GFP_KERNEL);
	if (!mep)
		goto fail_free_command_block;
	mep->esp = esp;
	platform_set_drvdata(dev, mep);

	switch (macintosh_config->scsi_type) {
	case MAC_SCSI_QUADRA:
		esp->cfreq     = 16500000;
		esp->regs      = (void __iomem *)MAC_ESP_REGS_QUADRA;
		mep->pdma_io   = esp->regs + MAC_ESP_PDMA_IO_OFFSET;
		mep->pdma_regs = NULL;
		break;
	case MAC_SCSI_QUADRA2:
		esp->cfreq     = 25000000;
		esp->regs      = (void __iomem *)(MAC_ESP_REGS_QUADRA2 +
				 dev->id * MAC_ESP_REGS_SPACING);
		mep->pdma_io   = esp->regs + MAC_ESP_PDMA_IO_OFFSET;
		mep->pdma_regs = (void __iomem *)(MAC_ESP_PDMA_REG +
				 dev->id * MAC_ESP_PDMA_REG_SPACING);
		nubus_writel(0x1d1, mep->pdma_regs);
		break;
	case MAC_SCSI_QUADRA3:
		/* These quadras have a real DMA controller (the PSC) but we
		 * don't know how to drive it so we must use PIO instead.
		 */
		esp->cfreq     = 25000000;
		esp->regs      = (void __iomem *)MAC_ESP_REGS_QUADRA3;
		mep->pdma_io   = NULL;
		mep->pdma_regs = NULL;
		break;
	}

	esp->ops = &mac_esp_ops;
	if (mep->pdma_io == NULL) {
		printk(KERN_INFO PFX "using PIO for controller %d\n", dev->id);
		esp_write8(0, ESP_TCLOW);
		esp_write8(0, ESP_TCMED);
		esp->flags = ESP_FLAG_DISABLE_SYNC;
		mac_esp_ops.send_dma_cmd = mac_esp_send_pio_cmd;
	} else {
		printk(KERN_INFO PFX "using PDMA for controller %d\n", dev->id);
	}

	host->irq = IRQ_MAC_SCSI;

	/* The request_irq() call is intended to succeed for the first device
	 * and fail for the second device.
	 */
	err = request_irq(host->irq, mac_scsi_esp_intr, 0, "ESP", NULL);
	spin_lock(&esp_chips_lock);
	if (err < 0 && esp_chips[!dev->id] == NULL) {
		spin_unlock(&esp_chips_lock);
		goto fail_free_priv;
	}
	esp_chips[dev->id] = esp;
	spin_unlock(&esp_chips_lock);

	err = scsi_esp_register(esp, &dev->dev);
	if (err)
		goto fail_free_irq;

	return 0;

fail_free_irq:
	spin_lock(&esp_chips_lock);
	esp_chips[dev->id] = NULL;
	if (esp_chips[!dev->id] == NULL) {
		spin_unlock(&esp_chips_lock);
		free_irq(host->irq, NULL);
	} else
		spin_unlock(&esp_chips_lock);
fail_free_priv:
	kfree(mep);
fail_free_command_block:
	kfree(esp->command_block);
fail_unlink:
	scsi_host_put(host);
fail:
	return err;
}

static int esp_mac_remove(struct platform_device *dev)
{
	struct mac_esp_priv *mep = platform_get_drvdata(dev);
	struct esp *esp = mep->esp;
	unsigned int irq = esp->host->irq;

	scsi_esp_unregister(esp);

	spin_lock(&esp_chips_lock);
	esp_chips[dev->id] = NULL;
	if (esp_chips[!dev->id] == NULL) {
		spin_unlock(&esp_chips_lock);
		free_irq(irq, NULL);
	} else
		spin_unlock(&esp_chips_lock);

	kfree(mep);

	kfree(esp->command_block);

	scsi_host_put(esp->host);

	return 0;
}

static struct platform_driver esp_mac_driver = {
	.probe    = esp_mac_probe,
	.remove   = esp_mac_remove,
	.driver   = {
		.name	= DRV_MODULE_NAME,
	},
};

static int __init mac_esp_init(void)
{
	return platform_driver_register(&esp_mac_driver);
}

static void __exit mac_esp_exit(void)
{
	platform_driver_unregister(&esp_mac_driver);
}

MODULE_DESCRIPTION("Mac ESP SCSI driver");
MODULE_AUTHOR("Finn Thain");
MODULE_LICENSE("GPL v2");
MODULE_VERSION(DRV_VERSION);
MODULE_ALIAS("platform:" DRV_MODULE_NAME);

module_init(mac_esp_init);
module_exit(mac_esp_exit);
Commit	Line	Data
6fe07aaf FT	1	/* mac_esp.c: ESP front-end for Macintosh Quadra systems.
	2	*
	3	* Adapted from jazz_esp.c and the old mac_esp.c.
	4	*
	5	* The pseudo DMA algorithm is based on the one used in NetBSD.
	6	* See sys/arch/mac68k/obio/esp.c for some background information.
	7	*
	8	* Copyright (C) 2007-2008 Finn Thain
	9	*/
	10
	11	#include <linux/kernel.h>
	12	#include <linux/types.h>
	13	#include <linux/module.h>
	14	#include <linux/init.h>
	15	#include <linux/interrupt.h>
	16	#include <linux/platform_device.h>
	17	#include <linux/dma-mapping.h>
	18	#include <linux/scatterlist.h>
	19	#include <linux/delay.h>
	20	#include <linux/io.h>
	21	#include <linux/nubus.h>
5a0e3ad6	22	#include <linux/slab.h>
6fe07aaf FT	23
	24	#include <asm/irq.h>
	25	#include <asm/dma.h>
6fe07aaf FT	26	#include <asm/macints.h>
6fe07aaf FT	27	#include <asm/macintosh.h>
30c0527d	28	#include <asm/mac_via.h>
6fe07aaf FT	29
	30	#include <scsi/scsi_host.h>
	31
	32	#include "esp_scsi.h"
	33
	34	#define DRV_MODULE_NAME "mac_esp"
	35	#define PFX DRV_MODULE_NAME ": "
	36	#define DRV_VERSION "1.000"
	37	#define DRV_MODULE_RELDATE "Sept 15, 2007"
	38
	39	#define MAC_ESP_IO_BASE 0x50F00000
	40	#define MAC_ESP_REGS_QUADRA (MAC_ESP_IO_BASE + 0x10000)
	41	#define MAC_ESP_REGS_QUADRA2 (MAC_ESP_IO_BASE + 0xF000)
	42	#define MAC_ESP_REGS_QUADRA3 (MAC_ESP_IO_BASE + 0x18000)
	43	#define MAC_ESP_REGS_SPACING 0x402
	44	#define MAC_ESP_PDMA_REG 0xF9800024
	45	#define MAC_ESP_PDMA_REG_SPACING 0x4
	46	#define MAC_ESP_PDMA_IO_OFFSET 0x100
	47
	48	#define esp_read8(REG) mac_esp_read8(esp, REG)
	49	#define esp_write8(VAL, REG) mac_esp_write8(esp, VAL, REG)
	50
	51	struct mac_esp_priv {
	52	struct esp *esp;
	53	void __iomem *pdma_regs;
	54	void __iomem *pdma_io;
	55	int error;
	56	};
da244654	57	static struct esp *esp_chips[2];
4da2b1eb	58	static DEFINE_SPINLOCK(esp_chips_lock);
6fe07aaf FT	59
	60	#define MAC_ESP_GET_PRIV(esp) ((struct mac_esp_priv *) \
	61	platform_get_drvdata((struct platform_device *) \
	62	(esp->dev)))
	63
	64	static inline void mac_esp_write8(struct esp *esp, u8 val, unsigned long reg)
	65	{
	66	nubus_writeb(val, esp->regs + reg * 16);
	67	}
	68
	69	static inline u8 mac_esp_read8(struct esp *esp, unsigned long reg)
	70	{
	71	return nubus_readb(esp->regs + reg * 16);
	72	}
	73
	74	/* For pseudo DMA and PIO we need the virtual address
	75	* so this address mapping is the identity mapping.
	76	*/
	77
	78	static dma_addr_t mac_esp_map_single(struct esp esp, void buf,
	79	size_t sz, int dir)
	80	{
	81	return (dma_addr_t)buf;
	82	}
	83
	84	static int mac_esp_map_sg(struct esp esp, struct scatterlist sg,
	85	int num_sg, int dir)
	86	{
	87	int i;
	88
	89	for (i = 0; i < num_sg; i++)
	90	sg[i].dma_address = (u32)sg_virt(&sg[i]);
	91	return num_sg;
	92	}
	93
	94	static void mac_esp_unmap_single(struct esp *esp, dma_addr_t addr,
	95	size_t sz, int dir)
	96	{
	97	/* Nothing to do. */
	98	}
	99
	100	static void mac_esp_unmap_sg(struct esp esp, struct scatterlist sg,
	101	int num_sg, int dir)
	102	{
	103	/* Nothing to do. */
	104	}
	105
	106	static void mac_esp_reset_dma(struct esp *esp)
	107	{
	108	/* Nothing to do. */
	109	}
	110
	111	static void mac_esp_dma_drain(struct esp *esp)
	112	{
	113	/* Nothing to do. */
	114	}
	115
	116	static void mac_esp_dma_invalidate(struct esp *esp)
	117	{
	118	/* Nothing to do. */
	119	}
	120
	121	static int mac_esp_dma_error(struct esp *esp)
	122	{
123	return MAC_ESP_GET_PRIV(esp)->error;
124	}
125
126	static inline int mac_esp_wait_for_empty_fifo(struct esp *esp)
127	{
128	struct mac_esp_priv *mep = MAC_ESP_GET_PRIV(esp);
129	int i = 500000;
130
131	do {
132	if (!(esp_read8(ESP_FFLAGS) & ESP_FF_FBYTES))
133	return 0;
134
135	if (esp_read8(ESP_STATUS) & ESP_STAT_INTR)
136	return 1;
137
138	udelay(2);
139	} while (--i);
140
141	printk(KERN_ERR PFX "FIFO is not empty (sreg %02x)\n",
142	esp_read8(ESP_STATUS));
143	mep->error = 1;
144	return 1;
145	}
146
147	static inline int mac_esp_wait_for_dreq(struct esp *esp)
148	{
149	struct mac_esp_priv *mep = MAC_ESP_GET_PRIV(esp);
150	int i = 500000;
151
152	do {
153	if (mep->pdma_regs == NULL) {
30c0527d	154	if (via2_scsi_drq_pending())
6fe07aaf FT	155	return 0;
	156	} else {
	157	if (nubus_readl(mep->pdma_regs) & 0x200)
	158	return 0;
	159	}
	160
	161	if (esp_read8(ESP_STATUS) & ESP_STAT_INTR)
	162	return 1;
	163
	164	udelay(2);
	165	} while (--i);
	166
	167	printk(KERN_ERR PFX "PDMA timeout (sreg %02x)\n",
	168	esp_read8(ESP_STATUS));
	169	mep->error = 1;
	170	return 1;
	171	}
	172
	173	#define MAC_ESP_PDMA_LOOP(operands) \
	174	asm volatile ( \
09e13e91	175	" tstw %1 \n" \
6fe07aaf FT	176	" jbeq 20f \n" \
	177	"1: movew " operands " \n" \
	178	"2: movew " operands " \n" \
	179	"3: movew " operands " \n" \
	180	"4: movew " operands " \n" \
	181	"5: movew " operands " \n" \
	182	"6: movew " operands " \n" \
	183	"7: movew " operands " \n" \
	184	"8: movew " operands " \n" \
	185	"9: movew " operands " \n" \
	186	"10: movew " operands " \n" \
	187	"11: movew " operands " \n" \
	188	"12: movew " operands " \n" \
	189	"13: movew " operands " \n" \
	190	"14: movew " operands " \n" \
	191	"15: movew " operands " \n" \
	192	"16: movew " operands " \n" \
09e13e91	193	" subqw #1,%1 \n" \
6fe07aaf	194	" jbne 1b \n" \
09e13e91	195	"20: tstw %2 \n" \
6fe07aaf FT	196	" jbeq 30f \n" \
6fe07aaf FT	197	"21: movew " operands " \n" \
09e13e91	198	" subqw #1,%2 \n" \
6fe07aaf	199	" jbne 21b \n" \
09e13e91	200	"30: tstw %3 \n" \
6fe07aaf FT	201	" jbeq 40f \n" \
	202	"31: moveb " operands " \n" \
	203	"32: nop \n" \
	204	"40: \n" \
	205	" \n" \
	206	" .section __ex_table,\"a\" \n" \
	207	" .align 4 \n" \
	208	" .long 1b,40b \n" \
	209	" .long 2b,40b \n" \
	210	" .long 3b,40b \n" \
	211	" .long 4b,40b \n" \
	212	" .long 5b,40b \n" \
	213	" .long 6b,40b \n" \
	214	" .long 7b,40b \n" \
	215	" .long 8b,40b \n" \
	216	" .long 9b,40b \n" \
	217	" .long 10b,40b \n" \
	218	" .long 11b,40b \n" \
	219	" .long 12b,40b \n" \
	220	" .long 13b,40b \n" \
	221	" .long 14b,40b \n" \
	222	" .long 15b,40b \n" \
	223	" .long 16b,40b \n" \
	224	" .long 21b,40b \n" \
	225	" .long 31b,40b \n" \
	226	" .long 32b,40b \n" \
	227	" .previous \n" \
09e13e91 FT	228	: "+a" (addr), "+r" (count32), "+r" (count2) \
09e13e91 FT	229	: "g" (count1), "a" (mep->pdma_io))
6fe07aaf FT	230
	231	static void mac_esp_send_pdma_cmd(struct esp *esp, u32 addr, u32 esp_count,
	232	u32 dma_count, int write, u8 cmd)
	233	{
	234	struct mac_esp_priv *mep = MAC_ESP_GET_PRIV(esp);
6fe07aaf FT	235
	236	mep->error = 0;
	237
	238	if (!write)
	239	scsi_esp_cmd(esp, ESP_CMD_FLUSH);
	240
	241	esp_write8((esp_count >> 0) & 0xFF, ESP_TCLOW);
	242	esp_write8((esp_count >> 8) & 0xFF, ESP_TCMED);
	243
	244	scsi_esp_cmd(esp, cmd);
	245
	246	do {
	247	unsigned int count32 = esp_count >> 5;
	248	unsigned int count2 = (esp_count & 0x1F) >> 1;
09e13e91	249	unsigned int count1 = esp_count & 1;
6fe07aaf FT	250	unsigned int start_addr = addr;
	251
	252	if (mac_esp_wait_for_dreq(esp))
	253	break;
	254
	255	if (write) {
09e13e91	256	MAC_ESP_PDMA_LOOP("%4@,%0@+");
6fe07aaf FT	257
	258	esp_count -= addr - start_addr;
	259	} else {
	260	unsigned int n;
	261
09e13e91	262	MAC_ESP_PDMA_LOOP("%0@+,%4@");
6fe07aaf FT	263
	264	if (mac_esp_wait_for_empty_fifo(esp))
	265	break;
	266
	267	n = (esp_read8(ESP_TCMED) << 8) + esp_read8(ESP_TCLOW);
	268	addr = start_addr + esp_count - n;
	269	esp_count = n;
	270	}
	271	} while (esp_count);
6fe07aaf FT	272	}
	273
	274	/*
	275	* Programmed IO routines follow.
	276	*/
	277
02507a80	278	static inline unsigned int mac_esp_wait_for_fifo(struct esp *esp)
6fe07aaf FT	279	{
	280	int i = 500000;
	281
	282	do {
02507a80 FT	283	unsigned int fbytes = esp_read8(ESP_FFLAGS) & ESP_FF_FBYTES;
	284
	285	if (fbytes)
	286	return fbytes;
6fe07aaf FT	287
	288	udelay(2);
	289	} while (--i);
	290
	291	printk(KERN_ERR PFX "FIFO is empty (sreg %02x)\n",
	292	esp_read8(ESP_STATUS));
02507a80	293	return 0;
6fe07aaf FT	294	}
	295
	296	static inline int mac_esp_wait_for_intr(struct esp *esp)
	297	{
02507a80	298	struct mac_esp_priv *mep = MAC_ESP_GET_PRIV(esp);
6fe07aaf FT	299	int i = 500000;
	300
	301	do {
	302	esp->sreg = esp_read8(ESP_STATUS);
	303	if (esp->sreg & ESP_STAT_INTR)
	304	return 0;
	305
	306	udelay(2);
	307	} while (--i);
	308
	309	printk(KERN_ERR PFX "IRQ timeout (sreg %02x)\n", esp->sreg);
02507a80	310	mep->error = 1;
6fe07aaf FT	311	return 1;
	312	}
	313
	314	#define MAC_ESP_PIO_LOOP(operands, reg1) \
	315	asm volatile ( \
	316	"1: moveb " operands " \n" \
	317	" subqw #1,%1 \n" \
	318	" jbne 1b \n" \
	319	: "+a" (addr), "+r" (reg1) \
	320	: "a" (fifo))
	321
	322	#define MAC_ESP_PIO_FILL(operands, reg1) \
	323	asm volatile ( \
	324	" moveb " operands " \n" \
	325	" moveb " operands " \n" \
	326	" moveb " operands " \n" \
	327	" moveb " operands " \n" \
	328	" moveb " operands " \n" \
	329	" moveb " operands " \n" \
	330	" moveb " operands " \n" \
	331	" moveb " operands " \n" \
	332	" moveb " operands " \n" \
	333	" moveb " operands " \n" \
	334	" moveb " operands " \n" \
	335	" moveb " operands " \n" \
	336	" moveb " operands " \n" \
	337	" moveb " operands " \n" \
	338	" moveb " operands " \n" \
	339	" moveb " operands " \n" \
	340	" subqw #8,%1 \n" \
	341	" subqw #8,%1 \n" \
	342	: "+a" (addr), "+r" (reg1) \
	343	: "a" (fifo))
	344
	345	#define MAC_ESP_FIFO_SIZE 16
	346
	347	static void mac_esp_send_pio_cmd(struct esp *esp, u32 addr, u32 esp_count,
	348	u32 dma_count, int write, u8 cmd)
	349	{
6fe07aaf FT	350	struct mac_esp_priv *mep = MAC_ESP_GET_PRIV(esp);
	351	u8 fifo = esp->regs + ESP_FDATA 16;
	352
6fe07aaf FT	353	cmd &= ~ESP_CMD_DMA;
	354	mep->error = 0;
	355
	356	if (write) {
	357	scsi_esp_cmd(esp, cmd);
	358
02507a80 FT	359	while (1) {
	360	unsigned int n;
	361
	362	n = mac_esp_wait_for_fifo(esp);
	363	if (!n)
	364	break;
	365
	366	if (n > esp_count)
	367	n = esp_count;
	368	esp_count -= n;
	369
	370	MAC_ESP_PIO_LOOP("%2@,%0@+", n);
	371
	372	if (!esp_count)
	373	break;
	374
	375	if (mac_esp_wait_for_intr(esp))
	376	break;
	377
	378	if (((esp->sreg & ESP_STAT_PMASK) != ESP_DIP) &&
	379	((esp->sreg & ESP_STAT_PMASK) != ESP_MIP))
	380	break;
	381
	382	esp->ireg = esp_read8(ESP_INTRPT);
	383	if ((esp->ireg & (ESP_INTR_DC \| ESP_INTR_BSERV)) !=
	384	ESP_INTR_BSERV)
	385	break;
	386
	387	scsi_esp_cmd(esp, ESP_CMD_TI);
6fe07aaf FT	388	}
	389	} else {
	390	scsi_esp_cmd(esp, ESP_CMD_FLUSH);
	391
	392	if (esp_count >= MAC_ESP_FIFO_SIZE)
	393	MAC_ESP_PIO_FILL("%0@+,%2@", esp_count);
	394	else
	395	MAC_ESP_PIO_LOOP("%0@+,%2@", esp_count);
	396
	397	scsi_esp_cmd(esp, cmd);
6fe07aaf	398
02507a80 FT	399	while (esp_count) {
02507a80 FT	400	unsigned int n;
6fe07aaf	401
02507a80	402	if (mac_esp_wait_for_intr(esp))
6fe07aaf FT	403	break;
6fe07aaf FT	404
02507a80 FT	405	if (((esp->sreg & ESP_STAT_PMASK) != ESP_DOP) &&
	406	((esp->sreg & ESP_STAT_PMASK) != ESP_MOP))
	407	break;
6fe07aaf	408
6fe07aaf	409	esp->ireg = esp_read8(ESP_INTRPT);
02507a80 FT	410	if ((esp->ireg & (ESP_INTR_DC \| ESP_INTR_BSERV)) !=
02507a80 FT	411	ESP_INTR_BSERV)
6fe07aaf FT	412	break;
6fe07aaf FT	413
02507a80 FT	414	n = MAC_ESP_FIFO_SIZE -
02507a80 FT	415	(esp_read8(ESP_FFLAGS) & ESP_FF_FBYTES);
6fe07aaf FT	416	if (n > esp_count)
	417	n = esp_count;
	418
	419	if (n == MAC_ESP_FIFO_SIZE) {
	420	MAC_ESP_PIO_FILL("%0@+,%2@", esp_count);
	421	} else {
	422	esp_count -= n;
	423	MAC_ESP_PIO_LOOP("%0@+,%2@", n);
	424	}
	425
	426	scsi_esp_cmd(esp, ESP_CMD_TI);
	427	}
	428	}
6fe07aaf FT	429	}
	430
	431	static int mac_esp_irq_pending(struct esp *esp)
	432	{
	433	if (esp_read8(ESP_STATUS) & ESP_STAT_INTR)
	434	return 1;
	435	return 0;
	436	}
	437
	438	static u32 mac_esp_dma_length_limit(struct esp *esp, u32 dma_addr, u32 dma_len)
	439	{
	440	return dma_len > 0xFFFF ? 0xFFFF : dma_len;
	441	}
	442
da244654 FT	443	static irqreturn_t mac_scsi_esp_intr(int irq, void *dev_id)
	444	{
	445	int got_intr;
	446
	447	/*
	448	* This is an edge triggered IRQ, so we have to be careful to
	449	* avoid missing a transition when it is shared by two ESP devices.
	450	*/
	451
	452	do {
	453	got_intr = 0;
	454	if (esp_chips[0] &&
	455	(mac_esp_read8(esp_chips[0], ESP_STATUS) & ESP_STAT_INTR)) {
	456	(void)scsi_esp_intr(irq, esp_chips[0]);
	457	got_intr = 1;
	458	}
	459	if (esp_chips[1] &&
	460	(mac_esp_read8(esp_chips[1], ESP_STATUS) & ESP_STAT_INTR)) {
	461	(void)scsi_esp_intr(irq, esp_chips[1]);
	462	got_intr = 1;
	463	}
	464	} while (got_intr);
	465
	466	return IRQ_HANDLED;
	467	}
	468
6fe07aaf FT	469	static struct esp_driver_ops mac_esp_ops = {
	470	.esp_write8 = mac_esp_write8,
	471	.esp_read8 = mac_esp_read8,
	472	.map_single = mac_esp_map_single,
	473	.map_sg = mac_esp_map_sg,
	474	.unmap_single = mac_esp_unmap_single,
	475	.unmap_sg = mac_esp_unmap_sg,
	476	.irq_pending = mac_esp_irq_pending,
	477	.dma_length_limit = mac_esp_dma_length_limit,
	478	.reset_dma = mac_esp_reset_dma,
	479	.dma_drain = mac_esp_dma_drain,
	480	.dma_invalidate = mac_esp_dma_invalidate,
	481	.send_dma_cmd = mac_esp_send_pdma_cmd,
	482	.dma_error = mac_esp_dma_error,
	483	};
	484
6f039790	485	static int esp_mac_probe(struct platform_device *dev)
6fe07aaf FT	486	{
	487	struct scsi_host_template *tpnt = &scsi_esp_template;
	488	struct Scsi_Host *host;
	489	struct esp *esp;
	490	int err;
6fe07aaf FT	491	struct mac_esp_priv *mep;
	492
	493	if (!MACH_IS_MAC)
	494	return -ENODEV;
	495
cff75f1f	496	if (dev->id > 1)
6fe07aaf FT	497	return -ENODEV;
	498
	499	host = scsi_host_alloc(tpnt, sizeof(struct esp));
	500
	501	err = -ENOMEM;
	502	if (!host)
	503	goto fail;
	504
	505	host->max_id = 8;
	506	host->use_clustering = DISABLE_CLUSTERING;
	507	esp = shost_priv(host);
	508
	509	esp->host = host;
	510	esp->dev = dev;
	511
	512	esp->command_block = kzalloc(16, GFP_KERNEL);
	513	if (!esp->command_block)
	514	goto fail_unlink;
	515	esp->command_block_dma = (dma_addr_t)esp->command_block;
	516
	517	esp->scsi_id = 7;
	518	host->this_id = esp->scsi_id;
	519	esp->scsi_id_mask = 1 << esp->scsi_id;
	520
	521	mep = kzalloc(sizeof(struct mac_esp_priv), GFP_KERNEL);
	522	if (!mep)
	523	goto fail_free_command_block;
	524	mep->esp = esp;
	525	platform_set_drvdata(dev, mep);
	526
	527	switch (macintosh_config->scsi_type) {
	528	case MAC_SCSI_QUADRA:
	529	esp->cfreq = 16500000;
	530	esp->regs = (void __iomem *)MAC_ESP_REGS_QUADRA;
	531	mep->pdma_io = esp->regs + MAC_ESP_PDMA_IO_OFFSET;
	532	mep->pdma_regs = NULL;
	533	break;
	534	case MAC_SCSI_QUADRA2:
	535	esp->cfreq = 25000000;
	536	esp->regs = (void __iomem *)(MAC_ESP_REGS_QUADRA2 +
	537	dev->id * MAC_ESP_REGS_SPACING);
	538	mep->pdma_io = esp->regs + MAC_ESP_PDMA_IO_OFFSET;
	539	mep->pdma_regs = (void __iomem *)(MAC_ESP_PDMA_REG +
	540	dev->id * MAC_ESP_PDMA_REG_SPACING);
	541	nubus_writel(0x1d1, mep->pdma_regs);
	542	break;
	543	case MAC_SCSI_QUADRA3:
	544	/* These quadras have a real DMA controller (the PSC) but we
	545	* don't know how to drive it so we must use PIO instead.
	546	*/
	547	esp->cfreq = 25000000;
	548	esp->regs = (void __iomem *)MAC_ESP_REGS_QUADRA3;
	549	mep->pdma_io = NULL;
	550	mep->pdma_regs = NULL;
	551	break;
	552	}
	553
	554	esp->ops = &mac_esp_ops;
	555	if (mep->pdma_io == NULL) {
	556	printk(KERN_INFO PFX "using PIO for controller %d\n", dev->id);
	557	esp_write8(0, ESP_TCLOW);
	558	esp_write8(0, ESP_TCMED);
	559	esp->flags = ESP_FLAG_DISABLE_SYNC;
	560	mac_esp_ops.send_dma_cmd = mac_esp_send_pio_cmd;
561	} else {
562	printk(KERN_INFO PFX "using PDMA for controller %d\n", dev->id);
563	}
564
565	host->irq = IRQ_MAC_SCSI;
4da2b1eb FT	566
	567	/* The request_irq() call is intended to succeed for the first device
	568	* and fail for the second device.
	569	*/
	570	err = request_irq(host->irq, mac_scsi_esp_intr, 0, "ESP", NULL);
	571	spin_lock(&esp_chips_lock);
	572	if (err < 0 && esp_chips[!dev->id] == NULL) {
	573	spin_unlock(&esp_chips_lock);
	574	goto fail_free_priv;
da244654	575	}
4da2b1eb FT	576	esp_chips[dev->id] = esp;
4da2b1eb FT	577	spin_unlock(&esp_chips_lock);
6fe07aaf FT	578
	579	err = scsi_esp_register(esp, &dev->dev);
	580	if (err)
	581	goto fail_free_irq;
	582
	583	return 0;
	584
	585	fail_free_irq:
4da2b1eb FT	586	spin_lock(&esp_chips_lock);
	587	esp_chips[dev->id] = NULL;
	588	if (esp_chips[!dev->id] == NULL) {
	589	spin_unlock(&esp_chips_lock);
c0e3a6ac	590	free_irq(host->irq, NULL);
4da2b1eb FT	591	} else
4da2b1eb FT	592	spin_unlock(&esp_chips_lock);
6fe07aaf FT	593	fail_free_priv:
	594	kfree(mep);
	595	fail_free_command_block:
	596	kfree(esp->command_block);
	597	fail_unlink:
	598	scsi_host_put(host);
	599	fail:
	600	return err;
	601	}
	602
6f039790	603	static int esp_mac_remove(struct platform_device *dev)
6fe07aaf FT	604	{
	605	struct mac_esp_priv *mep = platform_get_drvdata(dev);
	606	struct esp *esp = mep->esp;
	607	unsigned int irq = esp->host->irq;
	608
	609	scsi_esp_unregister(esp);
	610
4da2b1eb	611	spin_lock(&esp_chips_lock);
da244654	612	esp_chips[dev->id] = NULL;
4da2b1eb FT	613	if (esp_chips[!dev->id] == NULL) {
4da2b1eb FT	614	spin_unlock(&esp_chips_lock);
da244654	615	free_irq(irq, NULL);
4da2b1eb FT	616	} else
4da2b1eb FT	617	spin_unlock(&esp_chips_lock);
6fe07aaf FT	618
	619	kfree(mep);
	620
	621	kfree(esp->command_block);
	622
	623	scsi_host_put(esp->host);
	624
	625	return 0;
	626	}
	627
	628	static struct platform_driver esp_mac_driver = {
	629	.probe = esp_mac_probe,
6f039790	630	.remove = esp_mac_remove,
6fe07aaf	631	.driver = {
cff75f1f	632	.name = DRV_MODULE_NAME,
6fe07aaf FT	633	},
	634	};
	635
	636	static int __init mac_esp_init(void)
	637	{
cff75f1f	638	return platform_driver_register(&esp_mac_driver);
6fe07aaf FT	639	}
	640
	641	static void __exit mac_esp_exit(void)
	642	{
	643	platform_driver_unregister(&esp_mac_driver);
6fe07aaf FT	644	}
	645
	646	MODULE_DESCRIPTION("Mac ESP SCSI driver");
d0c2c269	647	MODULE_AUTHOR("Finn Thain");
839cd310	648	MODULE_LICENSE("GPL v2");
6fe07aaf	649	MODULE_VERSION(DRV_VERSION);
cff75f1f	650	MODULE_ALIAS("platform:" DRV_MODULE_NAME);
6fe07aaf FT	651
	652	module_init(mac_esp_init);
	653	module_exit(mac_esp_exit);