eesox.c

内核linux2.4.20,可跟rtlinux3.2打补丁 组成实时linux系统,编译内核

/*
 *  linux/drivers/acorn/scsi/eesox.c
 *
 *  Copyright (C) 1997-2000 Russell King
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 *
 *  This driver is based on experimentation.  Hence, it may have made
 *  assumptions about the particular card that I have available, and
 *  may not be reliable!
 *
 *  Changelog:
 *   01-10-1997	RMK		Created, READONLY version
 *   15-02-1998	RMK		READ/WRITE version
 *				added DMA support and hardware definitions
 *   14-03-1998	RMK		Updated DMA support
 *				Added terminator control
 *   15-04-1998	RMK		Only do PIO if FAS216 will allow it.
 *   27-06-1998	RMK		Changed asm/delay.h to linux/delay.h
 *   02-04-2000	RMK	0.0.3	Fixed NO_IRQ/NO_DMA problem, updated for new
 *				error handling code.
 */
#include <linux/module.h>
#include <linux/blk.h>
#include <linux/kernel.h>
#include <linux/string.h>
#include <linux/ioport.h>
#include <linux/sched.h>
#include <linux/proc_fs.h>
#include <linux/unistd.h>
#include <linux/stat.h>
#include <linux/delay.h>
#include <linux/pci.h>
#include <linux/init.h>

#include <asm/io.h>
#include <asm/irq.h>
#include <asm/dma.h>
#include <asm/ecard.h>
#include <asm/pgtable.h>

#include "../../scsi/sd.h"
#include "../../scsi/hosts.h"
#include "fas216.h"

#include <scsi/scsicam.h>

/* Configuration */
#define EESOX_XTALFREQ		40
#define EESOX_ASYNC_PERIOD	200
#define EESOX_SYNC_DEPTH	7

/*
 * List of devices that the driver will recognise
 */
#define EESOXSCSI_LIST	{ MANU_EESOX, PROD_EESOX_SCSI2 }

#define EESOX_FAS216_OFFSET	0xc00
#define EESOX_FAS216_SHIFT	3

#define EESOX_STATUS		0xa00
#define EESOX_STAT_INTR		0x01
#define EESOX_STAT_DMA		0x02

#define EESOX_CONTROL		0xa00
#define EESOX_INTR_ENABLE	0x04
#define EESOX_TERM_ENABLE	0x02
#define EESOX_RESET		0x01

#define EESOX_DMA_OFFSET	0xe00

/*
 * Version
 */
#define VER_MAJOR	0
#define VER_MINOR	0
#define VER_PATCH	3

static struct expansion_card *ecs[MAX_ECARDS];

/*
 * Use term=0,1,0,0,0 to turn terminators on/off
 */
static int term[MAX_ECARDS] = { 1, 1, 1, 1, 1, 1, 1, 1 };

#define NR_SG	256

struct control {
	unsigned int	io_port;
	unsigned int	control;
};

typedef struct {
	FAS216_Info info;

	struct control control;

	unsigned int	dmaarea;	/* Pseudo DMA area	*/
	struct scatterlist sg[NR_SG];	/* Scatter DMA list	*/
} EESOXScsi_Info;

/* Prototype: void eesoxscsi_irqenable(ec, irqnr)
 * Purpose  : Enable interrupts on EESOX SCSI card
 * Params   : ec    - expansion card structure
 *          : irqnr - interrupt number
 */
static void
eesoxscsi_irqenable(struct expansion_card *ec, int irqnr)
{
	struct control *control = (struct control *)ec->irq_data;

	control->control |= EESOX_INTR_ENABLE;

	outb(control->control, control->io_port);
}

/* Prototype: void eesoxscsi_irqdisable(ec, irqnr)
 * Purpose  : Disable interrupts on EESOX SCSI card
 * Params   : ec    - expansion card structure
 *          : irqnr - interrupt number
 */
static void
eesoxscsi_irqdisable(struct expansion_card *ec, int irqnr)
{
	struct control *control = (struct control *)ec->irq_data;

	control->control &= ~EESOX_INTR_ENABLE;

	outb(control->control, control->io_port);
}

static const expansioncard_ops_t eesoxscsi_ops = {
	eesoxscsi_irqenable,
	eesoxscsi_irqdisable,
	NULL,
	NULL,
	NULL,
	NULL
};

/* Prototype: void eesoxscsi_terminator_ctl(*host, on_off)
 * Purpose  : Turn the EESOX SCSI terminators on or off
 * Params   : host   - card to turn on/off
 *          : on_off - !0 to turn on, 0 to turn off
 */
static void
eesoxscsi_terminator_ctl(struct Scsi_Host *host, int on_off)
{
	EESOXScsi_Info *info = (EESOXScsi_Info *)host->hostdata;
	unsigned long flags;

	save_flags_cli(flags);
	if (on_off)
		info->control.control |= EESOX_TERM_ENABLE;
	else
		info->control.control &= ~EESOX_TERM_ENABLE;
	restore_flags(flags);

	outb(info->control.control, info->control.io_port);
}

/* Prototype: void eesoxscsi_intr(irq, *dev_id, *regs)
 * Purpose  : handle interrupts from EESOX SCSI card
 * Params   : irq    - interrupt number
 *	      dev_id - user-defined (Scsi_Host structure)
 *	      regs   - processor registers at interrupt
 */
static void
eesoxscsi_intr(int irq, void *dev_id, struct pt_regs *regs)
{
	struct Scsi_Host *host = (struct Scsi_Host *)dev_id;

	fas216_intr(host);
}

/* Prototype: fasdmatype_t eesoxscsi_dma_setup(host, SCpnt, direction, min_type)
 * Purpose  : initialises DMA/PIO
 * Params   : host      - host
 *	      SCpnt     - command
 *	      direction - DMA on to/off of card
 *	      min_type  - minimum DMA support that we must have for this transfer
 * Returns  : type of transfer to be performed
 */
static fasdmatype_t
eesoxscsi_dma_setup(struct Scsi_Host *host, Scsi_Pointer *SCp,
		       fasdmadir_t direction, fasdmatype_t min_type)
{
	EESOXScsi_Info *info = (EESOXScsi_Info *)host->hostdata;
	int dmach = host->dma_channel;

	if (dmach != NO_DMA &&
	    (min_type == fasdma_real_all || SCp->this_residual >= 512)) {
		int bufs = SCp->buffers_residual;
		int pci_dir, dma_dir;

		if (bufs)
			memcpy(info->sg + 1, SCp->buffer + 1,
				sizeof(struct scatterlist) * bufs);
		info->sg[0].address = SCp->ptr;
		info->sg[0].page    = NULL;
		info->sg[0].length  = SCp->this_residual;

		if (direction == DMA_OUT)
			pci_dir = PCI_DMA_TODEVICE,
			dma_dir = DMA_MODE_WRITE;
		else
			pci_dir = PCI_DMA_FROMDEVICE,
			dma_dir = DMA_MODE_READ;

		pci_map_sg(NULL, info->sg, bufs + 1, pci_dir);

		disable_dma(dmach);
		set_dma_sg(dmach, info->sg, bufs + 1);
		set_dma_mode(dmach, dma_dir);
		enable_dma(dmach);
		return fasdma_real_all;
	}
	/*
	 * We don't do DMA, we only do slow PIO
	 *
	 * Some day, we will do Pseudo DMA
	 */
	return fasdma_pseudo;
}

static void
eesoxscsi_dma_pseudo(struct Scsi_Host *host, Scsi_Pointer *SCp,
		     fasdmadir_t dir, int transfer_size)
{
	EESOXScsi_Info *info = (EESOXScsi_Info *)host->hostdata;
	unsigned int status;
	unsigned int length = SCp->this_residual;
	union {
		unsigned char *c;
		unsigned short *s;
		unsigned long *l;
	} buffer;

	buffer.c = SCp->ptr;

	status = inb(host->io_port + EESOX_STATUS);
	if (dir == DMA_IN) {
		while (length > 8) {
			if (status & EESOX_STAT_DMA) {
				unsigned long l1, l2;

				l1 = inw(info->dmaarea);
				l1 |= inw(info->dmaarea) << 16;
				l2 = inw(info->dmaarea);
				l2 |= inw(info->dmaarea) << 16;
				*buffer.l++ = l1;
				*buffer.l++ = l2;
				length -= 8;
			} else if (status & EESOX_STAT_INTR)
				goto end;
			status = inb(host->io_port + EESOX_STATUS);
		}

		while (length > 1) {
			if (status & EESOX_STAT_DMA) {
				*buffer.s++ = inw(info->dmaarea);
				length -= 2;
			} else if (status & EESOX_STAT_INTR)
				goto end;
			status = inb(host->io_port + EESOX_STATUS);
		}

		while (length > 0) {
			if (status & EESOX_STAT_DMA) {
				*buffer.c++ = inw(info->dmaarea);
				length -= 1;
			} else if (status & EESOX_STAT_INTR)
				goto end;
			status = inb(host->io_port + EESOX_STATUS);
		}
	} else {
		while (length > 8) {
			if (status & EESOX_STAT_DMA) {
				unsigned long l1, l2;

				l1 = *buffer.l++;
				l2 = *buffer.l++;

				outw(l1, info->dmaarea);
				outw(l1 >> 16, info->dmaarea);
				outw(l2, info->dmaarea);
				outw(l2 >> 16, info->dmaarea);
				length -= 8;
			} else if (status & EESOX_STAT_INTR)
				goto end;
			status = inb(host->io_port + EESOX_STATUS);
		}

		while (length > 1) {
			if (status & EESOX_STAT_DMA) {
				outw(*buffer.s++, info->dmaarea);
				length -= 2;
			} else if (status & EESOX_STAT_INTR)
				goto end;
			status = inb(host->io_port + EESOX_STATUS);
		}