[linux.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];

#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;
	esp_chips[dev->id] = esp;
	mb();
	if (esp_chips[!dev->id] == NULL) {
		err = request_irq(host->irq, mac_scsi_esp_intr, 0, "ESP", NULL);
		if (err < 0) {
			esp_chips[dev->id] = NULL;
			goto fail_free_priv;
		}
	}

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

	return 0;

fail_free_irq:
	if (esp_chips[!dev->id] == NULL)
		free_irq(host->irq, esp);
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);

	esp_chips[dev->id] = NULL;
	if (!(esp_chips[0] || esp_chips[1]))
		free_irq(irq, NULL);

	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,
		.owner	= THIS_MODULE,
	},
};

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 <[email protected]>");
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];
6fe07aaf FT	58
	59	#define MAC_ESP_GET_PRIV(esp) ((struct mac_esp_priv *) \
	60	platform_get_drvdata((struct platform_device *) \
	61	(esp->dev)))
	62
	63	static inline void mac_esp_write8(struct esp *esp, u8 val, unsigned long reg)
	64	{
	65	nubus_writeb(val, esp->regs + reg * 16);
	66	}
	67
	68	static inline u8 mac_esp_read8(struct esp *esp, unsigned long reg)
	69	{
	70	return nubus_readb(esp->regs + reg * 16);
	71	}
	72
	73	/* For pseudo DMA and PIO we need the virtual address
	74	* so this address mapping is the identity mapping.
	75	*/
	76
	77	static dma_addr_t mac_esp_map_single(struct esp esp, void buf,
	78	size_t sz, int dir)
	79	{
	80	return (dma_addr_t)buf;
	81	}
	82
	83	static int mac_esp_map_sg(struct esp esp, struct scatterlist sg,
	84	int num_sg, int dir)
	85	{
	86	int i;
	87
	88	for (i = 0; i < num_sg; i++)
	89	sg[i].dma_address = (u32)sg_virt(&sg[i]);
	90	return num_sg;
	91	}
	92
	93	static void mac_esp_unmap_single(struct esp *esp, dma_addr_t addr,
	94	size_t sz, int dir)
	95	{
	96	/* Nothing to do. */
	97	}
	98
	99	static void mac_esp_unmap_sg(struct esp esp, struct scatterlist sg,
	100	int num_sg, int dir)
	101	{
	102	/* Nothing to do. */
	103	}
	104
	105	static void mac_esp_reset_dma(struct esp *esp)
	106	{
	107	/* Nothing to do. */
	108	}
	109
	110	static void mac_esp_dma_drain(struct esp *esp)
	111	{
	112	/* Nothing to do. */
	113	}
	114
	115	static void mac_esp_dma_invalidate(struct esp *esp)
	116	{
	117	/* Nothing to do. */
	118	}
	119
	120	static int mac_esp_dma_error(struct esp *esp)
	121	{
122	return MAC_ESP_GET_PRIV(esp)->error;
123	}
124
125	static inline int mac_esp_wait_for_empty_fifo(struct esp *esp)
126	{
127	struct mac_esp_priv *mep = MAC_ESP_GET_PRIV(esp);
128	int i = 500000;
129
130	do {
131	if (!(esp_read8(ESP_FFLAGS) & ESP_FF_FBYTES))
132	return 0;
133
134	if (esp_read8(ESP_STATUS) & ESP_STAT_INTR)
135	return 1;
136
137	udelay(2);
138	} while (--i);
139
140	printk(KERN_ERR PFX "FIFO is not empty (sreg %02x)\n",
141	esp_read8(ESP_STATUS));
142	mep->error = 1;
143	return 1;
144	}
145
146	static inline int mac_esp_wait_for_dreq(struct esp *esp)
147	{
148	struct mac_esp_priv *mep = MAC_ESP_GET_PRIV(esp);
149	int i = 500000;
150
151	do {
152	if (mep->pdma_regs == NULL) {
30c0527d	153	if (via2_scsi_drq_pending())
6fe07aaf FT	154	return 0;
	155	} else {
	156	if (nubus_readl(mep->pdma_regs) & 0x200)
	157	return 0;
	158	}
	159
	160	if (esp_read8(ESP_STATUS) & ESP_STAT_INTR)
	161	return 1;
	162
	163	udelay(2);
	164	} while (--i);
	165
	166	printk(KERN_ERR PFX "PDMA timeout (sreg %02x)\n",
	167	esp_read8(ESP_STATUS));
	168	mep->error = 1;
	169	return 1;
	170	}
	171
	172	#define MAC_ESP_PDMA_LOOP(operands) \
	173	asm volatile ( \
09e13e91	174	" tstw %1 \n" \
6fe07aaf FT	175	" jbeq 20f \n" \
	176	"1: movew " operands " \n" \
	177	"2: movew " operands " \n" \
	178	"3: movew " operands " \n" \
	179	"4: movew " operands " \n" \
	180	"5: movew " operands " \n" \
	181	"6: movew " operands " \n" \
	182	"7: movew " operands " \n" \
	183	"8: movew " operands " \n" \
	184	"9: movew " operands " \n" \
	185	"10: movew " operands " \n" \
	186	"11: movew " operands " \n" \
	187	"12: movew " operands " \n" \
	188	"13: movew " operands " \n" \
	189	"14: movew " operands " \n" \
	190	"15: movew " operands " \n" \
	191	"16: movew " operands " \n" \
09e13e91	192	" subqw #1,%1 \n" \
6fe07aaf	193	" jbne 1b \n" \
09e13e91	194	"20: tstw %2 \n" \
6fe07aaf FT	195	" jbeq 30f \n" \
6fe07aaf FT	196	"21: movew " operands " \n" \
09e13e91	197	" subqw #1,%2 \n" \
6fe07aaf	198	" jbne 21b \n" \
09e13e91	199	"30: tstw %3 \n" \
6fe07aaf FT	200	" jbeq 40f \n" \
	201	"31: moveb " operands " \n" \
	202	"32: nop \n" \
	203	"40: \n" \
	204	" \n" \
	205	" .section __ex_table,\"a\" \n" \
	206	" .align 4 \n" \
	207	" .long 1b,40b \n" \
	208	" .long 2b,40b \n" \
	209	" .long 3b,40b \n" \
	210	" .long 4b,40b \n" \
	211	" .long 5b,40b \n" \
	212	" .long 6b,40b \n" \
	213	" .long 7b,40b \n" \
	214	" .long 8b,40b \n" \
	215	" .long 9b,40b \n" \
	216	" .long 10b,40b \n" \
	217	" .long 11b,40b \n" \
	218	" .long 12b,40b \n" \
	219	" .long 13b,40b \n" \
	220	" .long 14b,40b \n" \
	221	" .long 15b,40b \n" \
	222	" .long 16b,40b \n" \
	223	" .long 21b,40b \n" \
	224	" .long 31b,40b \n" \
	225	" .long 32b,40b \n" \
	226	" .previous \n" \
09e13e91 FT	227	: "+a" (addr), "+r" (count32), "+r" (count2) \
09e13e91 FT	228	: "g" (count1), "a" (mep->pdma_io))
6fe07aaf FT	229
	230	static void mac_esp_send_pdma_cmd(struct esp *esp, u32 addr, u32 esp_count,
	231	u32 dma_count, int write, u8 cmd)
	232	{
	233	struct mac_esp_priv *mep = MAC_ESP_GET_PRIV(esp);
6fe07aaf FT	234
	235	mep->error = 0;
	236
	237	if (!write)
	238	scsi_esp_cmd(esp, ESP_CMD_FLUSH);
	239
	240	esp_write8((esp_count >> 0) & 0xFF, ESP_TCLOW);
	241	esp_write8((esp_count >> 8) & 0xFF, ESP_TCMED);
	242
	243	scsi_esp_cmd(esp, cmd);
	244
	245	do {
	246	unsigned int count32 = esp_count >> 5;
	247	unsigned int count2 = (esp_count & 0x1F) >> 1;
09e13e91	248	unsigned int count1 = esp_count & 1;
6fe07aaf FT	249	unsigned int start_addr = addr;
	250
	251	if (mac_esp_wait_for_dreq(esp))
	252	break;
	253
	254	if (write) {
09e13e91	255	MAC_ESP_PDMA_LOOP("%4@,%0@+");
6fe07aaf FT	256
	257	esp_count -= addr - start_addr;
	258	} else {
	259	unsigned int n;
	260
09e13e91	261	MAC_ESP_PDMA_LOOP("%0@+,%4@");
6fe07aaf FT	262
	263	if (mac_esp_wait_for_empty_fifo(esp))
	264	break;
	265
	266	n = (esp_read8(ESP_TCMED) << 8) + esp_read8(ESP_TCLOW);
	267	addr = start_addr + esp_count - n;
	268	esp_count = n;
	269	}
	270	} while (esp_count);
6fe07aaf FT	271	}
	272
	273	/*
	274	* Programmed IO routines follow.
	275	*/
	276
02507a80	277	static inline unsigned int mac_esp_wait_for_fifo(struct esp *esp)
6fe07aaf FT	278	{
	279	int i = 500000;
	280
	281	do {
02507a80 FT	282	unsigned int fbytes = esp_read8(ESP_FFLAGS) & ESP_FF_FBYTES;
	283
	284	if (fbytes)
	285	return fbytes;
6fe07aaf FT	286
	287	udelay(2);
	288	} while (--i);
	289
	290	printk(KERN_ERR PFX "FIFO is empty (sreg %02x)\n",
	291	esp_read8(ESP_STATUS));
02507a80	292	return 0;
6fe07aaf FT	293	}
	294
	295	static inline int mac_esp_wait_for_intr(struct esp *esp)
	296	{
02507a80	297	struct mac_esp_priv *mep = MAC_ESP_GET_PRIV(esp);
6fe07aaf FT	298	int i = 500000;
	299
	300	do {
	301	esp->sreg = esp_read8(ESP_STATUS);
	302	if (esp->sreg & ESP_STAT_INTR)
	303	return 0;
	304
	305	udelay(2);
	306	} while (--i);
	307
	308	printk(KERN_ERR PFX "IRQ timeout (sreg %02x)\n", esp->sreg);
02507a80	309	mep->error = 1;
6fe07aaf FT	310	return 1;
	311	}
	312
	313	#define MAC_ESP_PIO_LOOP(operands, reg1) \
	314	asm volatile ( \
	315	"1: moveb " operands " \n" \
	316	" subqw #1,%1 \n" \
	317	" jbne 1b \n" \
	318	: "+a" (addr), "+r" (reg1) \
	319	: "a" (fifo))
	320
	321	#define MAC_ESP_PIO_FILL(operands, reg1) \
	322	asm volatile ( \
	323	" moveb " operands " \n" \
	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	" subqw #8,%1 \n" \
	340	" subqw #8,%1 \n" \
	341	: "+a" (addr), "+r" (reg1) \
	342	: "a" (fifo))
	343
	344	#define MAC_ESP_FIFO_SIZE 16
	345
	346	static void mac_esp_send_pio_cmd(struct esp *esp, u32 addr, u32 esp_count,
	347	u32 dma_count, int write, u8 cmd)
	348	{
6fe07aaf FT	349	struct mac_esp_priv *mep = MAC_ESP_GET_PRIV(esp);
	350	u8 fifo = esp->regs + ESP_FDATA 16;
	351
6fe07aaf FT	352	cmd &= ~ESP_CMD_DMA;
	353	mep->error = 0;
	354
	355	if (write) {
	356	scsi_esp_cmd(esp, cmd);
	357
02507a80 FT	358	while (1) {
	359	unsigned int n;
	360
	361	n = mac_esp_wait_for_fifo(esp);
	362	if (!n)
	363	break;
	364
	365	if (n > esp_count)
	366	n = esp_count;
	367	esp_count -= n;
	368
	369	MAC_ESP_PIO_LOOP("%2@,%0@+", n);
	370
	371	if (!esp_count)
	372	break;
	373
	374	if (mac_esp_wait_for_intr(esp))
	375	break;
	376
	377	if (((esp->sreg & ESP_STAT_PMASK) != ESP_DIP) &&
	378	((esp->sreg & ESP_STAT_PMASK) != ESP_MIP))
	379	break;
	380
	381	esp->ireg = esp_read8(ESP_INTRPT);
	382	if ((esp->ireg & (ESP_INTR_DC \| ESP_INTR_BSERV)) !=
	383	ESP_INTR_BSERV)
	384	break;
	385
	386	scsi_esp_cmd(esp, ESP_CMD_TI);
6fe07aaf FT	387	}
	388	} else {
	389	scsi_esp_cmd(esp, ESP_CMD_FLUSH);
	390
	391	if (esp_count >= MAC_ESP_FIFO_SIZE)
	392	MAC_ESP_PIO_FILL("%0@+,%2@", esp_count);
	393	else
	394	MAC_ESP_PIO_LOOP("%0@+,%2@", esp_count);
	395
	396	scsi_esp_cmd(esp, cmd);
6fe07aaf	397
02507a80 FT	398	while (esp_count) {
02507a80 FT	399	unsigned int n;
6fe07aaf	400
02507a80	401	if (mac_esp_wait_for_intr(esp))
6fe07aaf FT	402	break;
6fe07aaf FT	403
02507a80 FT	404	if (((esp->sreg & ESP_STAT_PMASK) != ESP_DOP) &&
	405	((esp->sreg & ESP_STAT_PMASK) != ESP_MOP))
	406	break;
6fe07aaf	407
6fe07aaf	408	esp->ireg = esp_read8(ESP_INTRPT);
02507a80 FT	409	if ((esp->ireg & (ESP_INTR_DC \| ESP_INTR_BSERV)) !=
02507a80 FT	410	ESP_INTR_BSERV)
6fe07aaf FT	411	break;
6fe07aaf FT	412
02507a80 FT	413	n = MAC_ESP_FIFO_SIZE -
02507a80 FT	414	(esp_read8(ESP_FFLAGS) & ESP_FF_FBYTES);
6fe07aaf FT	415	if (n > esp_count)
	416	n = esp_count;
	417
	418	if (n == MAC_ESP_FIFO_SIZE) {
	419	MAC_ESP_PIO_FILL("%0@+,%2@", esp_count);
	420	} else {
	421	esp_count -= n;
	422	MAC_ESP_PIO_LOOP("%0@+,%2@", n);
	423	}
	424
	425	scsi_esp_cmd(esp, ESP_CMD_TI);
	426	}
	427	}
6fe07aaf FT	428	}
	429
	430	static int mac_esp_irq_pending(struct esp *esp)
	431	{
	432	if (esp_read8(ESP_STATUS) & ESP_STAT_INTR)
	433	return 1;
	434	return 0;
	435	}
	436
	437	static u32 mac_esp_dma_length_limit(struct esp *esp, u32 dma_addr, u32 dma_len)
	438	{
	439	return dma_len > 0xFFFF ? 0xFFFF : dma_len;
	440	}
	441
da244654 FT	442	static irqreturn_t mac_scsi_esp_intr(int irq, void *dev_id)
	443	{
	444	int got_intr;
	445
	446	/*
	447	* This is an edge triggered IRQ, so we have to be careful to
	448	* avoid missing a transition when it is shared by two ESP devices.
	449	*/
	450
	451	do {
	452	got_intr = 0;
	453	if (esp_chips[0] &&
	454	(mac_esp_read8(esp_chips[0], ESP_STATUS) & ESP_STAT_INTR)) {
	455	(void)scsi_esp_intr(irq, esp_chips[0]);
	456	got_intr = 1;
	457	}
	458	if (esp_chips[1] &&
	459	(mac_esp_read8(esp_chips[1], ESP_STATUS) & ESP_STAT_INTR)) {
	460	(void)scsi_esp_intr(irq, esp_chips[1]);
	461	got_intr = 1;
	462	}
	463	} while (got_intr);
	464
	465	return IRQ_HANDLED;
	466	}
	467
6fe07aaf FT	468	static struct esp_driver_ops mac_esp_ops = {
	469	.esp_write8 = mac_esp_write8,
	470	.esp_read8 = mac_esp_read8,
	471	.map_single = mac_esp_map_single,
	472	.map_sg = mac_esp_map_sg,
	473	.unmap_single = mac_esp_unmap_single,
	474	.unmap_sg = mac_esp_unmap_sg,
	475	.irq_pending = mac_esp_irq_pending,
	476	.dma_length_limit = mac_esp_dma_length_limit,
	477	.reset_dma = mac_esp_reset_dma,
	478	.dma_drain = mac_esp_dma_drain,
	479	.dma_invalidate = mac_esp_dma_invalidate,
	480	.send_dma_cmd = mac_esp_send_pdma_cmd,
	481	.dma_error = mac_esp_dma_error,
	482	};
	483
6f039790	484	static int esp_mac_probe(struct platform_device *dev)
6fe07aaf FT	485	{
	486	struct scsi_host_template *tpnt = &scsi_esp_template;
	487	struct Scsi_Host *host;
	488	struct esp *esp;
	489	int err;
6fe07aaf FT	490	struct mac_esp_priv *mep;
	491
	492	if (!MACH_IS_MAC)
	493	return -ENODEV;
	494
cff75f1f	495	if (dev->id > 1)
6fe07aaf FT	496	return -ENODEV;
	497
	498	host = scsi_host_alloc(tpnt, sizeof(struct esp));
	499
	500	err = -ENOMEM;
	501	if (!host)
	502	goto fail;
	503
	504	host->max_id = 8;
	505	host->use_clustering = DISABLE_CLUSTERING;
	506	esp = shost_priv(host);
	507
	508	esp->host = host;
	509	esp->dev = dev;
	510
	511	esp->command_block = kzalloc(16, GFP_KERNEL);
	512	if (!esp->command_block)
	513	goto fail_unlink;
	514	esp->command_block_dma = (dma_addr_t)esp->command_block;
	515
	516	esp->scsi_id = 7;
	517	host->this_id = esp->scsi_id;
	518	esp->scsi_id_mask = 1 << esp->scsi_id;
	519
	520	mep = kzalloc(sizeof(struct mac_esp_priv), GFP_KERNEL);
	521	if (!mep)
	522	goto fail_free_command_block;
	523	mep->esp = esp;
	524	platform_set_drvdata(dev, mep);
	525
	526	switch (macintosh_config->scsi_type) {
	527	case MAC_SCSI_QUADRA:
	528	esp->cfreq = 16500000;
	529	esp->regs = (void __iomem *)MAC_ESP_REGS_QUADRA;
	530	mep->pdma_io = esp->regs + MAC_ESP_PDMA_IO_OFFSET;
	531	mep->pdma_regs = NULL;
	532	break;
	533	case MAC_SCSI_QUADRA2:
	534	esp->cfreq = 25000000;
	535	esp->regs = (void __iomem *)(MAC_ESP_REGS_QUADRA2 +
	536	dev->id * MAC_ESP_REGS_SPACING);
	537	mep->pdma_io = esp->regs + MAC_ESP_PDMA_IO_OFFSET;
	538	mep->pdma_regs = (void __iomem *)(MAC_ESP_PDMA_REG +
	539	dev->id * MAC_ESP_PDMA_REG_SPACING);
	540	nubus_writel(0x1d1, mep->pdma_regs);
	541	break;
	542	case MAC_SCSI_QUADRA3:
	543	/* These quadras have a real DMA controller (the PSC) but we
	544	* don't know how to drive it so we must use PIO instead.
	545	*/
	546	esp->cfreq = 25000000;
	547	esp->regs = (void __iomem *)MAC_ESP_REGS_QUADRA3;
	548	mep->pdma_io = NULL;
	549	mep->pdma_regs = NULL;
	550	break;
	551	}
	552
	553	esp->ops = &mac_esp_ops;
	554	if (mep->pdma_io == NULL) {
	555	printk(KERN_INFO PFX "using PIO for controller %d\n", dev->id);
	556	esp_write8(0, ESP_TCLOW);
	557	esp_write8(0, ESP_TCMED);
	558	esp->flags = ESP_FLAG_DISABLE_SYNC;
	559	mac_esp_ops.send_dma_cmd = mac_esp_send_pio_cmd;
560	} else {
561	printk(KERN_INFO PFX "using PDMA for controller %d\n", dev->id);
562	}
563
564	host->irq = IRQ_MAC_SCSI;
da244654 FT	565	esp_chips[dev->id] = esp;
	566	mb();
	567	if (esp_chips[!dev->id] == NULL) {
c808d3d8	568	err = request_irq(host->irq, mac_scsi_esp_intr, 0, "ESP", NULL);
da244654 FT	569	if (err < 0) {
	570	esp_chips[dev->id] = NULL;
	571	goto fail_free_priv;
	572	}
	573	}
6fe07aaf FT	574
	575	err = scsi_esp_register(esp, &dev->dev);
	576	if (err)
	577	goto fail_free_irq;
	578
	579	return 0;
	580
	581	fail_free_irq:
da244654 FT	582	if (esp_chips[!dev->id] == NULL)
da244654 FT	583	free_irq(host->irq, esp);
6fe07aaf FT	584	fail_free_priv:
	585	kfree(mep);
	586	fail_free_command_block:
	587	kfree(esp->command_block);
	588	fail_unlink:
	589	scsi_host_put(host);
	590	fail:
	591	return err;
	592	}
	593
6f039790	594	static int esp_mac_remove(struct platform_device *dev)
6fe07aaf FT	595	{
	596	struct mac_esp_priv *mep = platform_get_drvdata(dev);
	597	struct esp *esp = mep->esp;
	598	unsigned int irq = esp->host->irq;
	599
	600	scsi_esp_unregister(esp);
	601
da244654 FT	602	esp_chips[dev->id] = NULL;
	603	if (!(esp_chips[0] \|\| esp_chips[1]))
	604	free_irq(irq, NULL);
6fe07aaf FT	605
	606	kfree(mep);
	607
	608	kfree(esp->command_block);
	609
	610	scsi_host_put(esp->host);
	611
	612	return 0;
	613	}
	614
	615	static struct platform_driver esp_mac_driver = {
	616	.probe = esp_mac_probe,
6f039790	617	.remove = esp_mac_remove,
6fe07aaf	618	.driver = {
cff75f1f FT	619	.name = DRV_MODULE_NAME,
cff75f1f FT	620	.owner = THIS_MODULE,
6fe07aaf FT	621	},
	622	};
	623
	624	static int __init mac_esp_init(void)
	625	{
cff75f1f	626	return platform_driver_register(&esp_mac_driver);
6fe07aaf FT	627	}
	628
	629	static void __exit mac_esp_exit(void)
	630	{
	631	platform_driver_unregister(&esp_mac_driver);
6fe07aaf FT	632	}
	633
	634	MODULE_DESCRIPTION("Mac ESP SCSI driver");
	635	MODULE_AUTHOR("Finn Thain <[email protected]>");
839cd310	636	MODULE_LICENSE("GPL v2");
6fe07aaf	637	MODULE_VERSION(DRV_VERSION);
cff75f1f	638	MODULE_ALIAS("platform:" DRV_MODULE_NAME);
6fe07aaf FT	639
	640	module_init(mac_esp_init);
	641	module_exit(mac_esp_exit);