patch-2.4.21 linux-2.4.21/drivers/ide/legacy/pdc4030.c

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diff -urN linux-2.4.20/drivers/ide/legacy/pdc4030.c linux-2.4.21/drivers/ide/legacy/pdc4030.c
@@ -0,0 +1,865 @@
+/*  -*- linux-c -*-
+ *  linux/drivers/ide/legacy/pdc4030.c		Version 0.90  May 27, 1999
+ *
+ *  Copyright (C) 1995-2002  Linus Torvalds & authors (see below)
+ */
+
+/*
+ *  Principal Author/Maintainer:  Peter Denison <promise@pnd-pc.demon.co.uk>
+ *
+ *  This file provides support for the second port and cache of Promise
+ *  IDE interfaces, e.g. DC4030VL, DC4030VL-1 and DC4030VL-2.
+ *
+ *  Thanks are due to Mark Lord for advice and patiently answering stupid
+ *  questions, and all those mugs^H^H^H^Hbrave souls who've tested this,
+ *  especially Andre Hedrick.
+ *
+ *  Version 0.01	Initial version, #include'd in ide.c rather than
+ *                      compiled separately.
+ *                      Reads use Promise commands, writes as before. Drives
+ *                      on second channel are read-only.
+ *  Version 0.02        Writes working on second channel, reads on both
+ *                      channels. Writes fail under high load. Suspect
+ *			transfers of >127 sectors don't work.
+ *  Version 0.03        Brought into line with ide.c version 5.27.
+ *                      Other minor changes.
+ *  Version 0.04        Updated for ide.c version 5.30
+ *                      Changed initialization strategy
+ *  Version 0.05	Kernel integration.  -ml
+ *  Version 0.06	Ooops. Add hwgroup to direct call of ide_intr() -ml
+ *  Version 0.07	Added support for DC4030 variants
+ *			Secondary interface autodetection
+ *  Version 0.08	Renamed to pdc4030.c
+ *  Version 0.09	Obsolete - never released - did manual write request
+ *			splitting before max_sectors[major][minor] available.
+ *  Version 0.10	Updated for 2.1 series of kernels
+ *  Version 0.11	Updated for 2.3 series of kernels
+ *			Autodetection code added.
+ *
+ *  Version 0.90	Transition to BETA code. No lost/unexpected interrupts
+ */
+
+/*
+ * Once you've compiled it in, you'll have to also enable the interface
+ * setup routine from the kernel command line, as in 
+ *
+ *	'linux ide0=dc4030' or 'linux ide1=dc4030'
+ *
+ * It should now work as a second controller also ('ide1=dc4030') but only
+ * if you DON'T have BIOS V4.44, which has a bug. If you have this version
+ * and EPROM programming facilities, you need to fix 4 bytes:
+ * 	2496:	81	81
+ *	2497:	3E	3E
+ *	2498:	22	98	*
+ *	2499:	06	05	*
+ *	249A:	F0	F0
+ *	249B:	01	01
+ *	...
+ *	24A7:	81	81
+ *	24A8:	3E	3E
+ *	24A9:	22	98	*
+ *	24AA:	06	05	*
+ *	24AB:	70	70
+ *	24AC:	01	01
+ *
+ * As of January 1999, Promise Technology Inc. have finally supplied me with
+ * some technical information which has shed a glimmer of light on some of the
+ * problems I was having, especially with writes. 
+ *
+ * There are still potential problems with the robustness and efficiency of
+ * this driver because I still don't understand what the card is doing with
+ * interrupts, however, it has been stable for a while with no reports of ill
+ * effects.
+ */
+
+#define DEBUG_READ
+#define DEBUG_WRITE
+#define __PROMISE_4030
+
+#include <linux/module.h>
+#include <linux/config.h>
+#include <linux/types.h>
+#include <linux/kernel.h>
+#include <linux/delay.h>
+#include <linux/timer.h>
+#include <linux/mm.h>
+#include <linux/ioport.h>
+#include <linux/blkdev.h>
+#include <linux/hdreg.h>
+#include <linux/ide.h>
+#include <linux/init.h>
+
+#include <asm/io.h>
+#include <asm/irq.h>
+
+#include "pdc4030.h"
+
+static ide_startstop_t promise_rw_disk (ide_drive_t *drive, struct request *rq, unsigned long block);
+
+/*
+ * promise_selectproc() is invoked by ide.c
+ * in preparation for access to the specified drive.
+ */
+static void promise_selectproc (ide_drive_t *drive)
+{
+	unsigned int number;
+
+	number = (HWIF(drive)->channel << 1) + drive->select.b.unit;
+	HWIF(drive)->OUTB(number, IDE_FEATURE_REG);
+}
+
+/*
+ * pdc4030_cmd handles the set of vendor specific commands that are initiated
+ * by command F0. They all have the same success/failure notification -
+ * 'P' (=0x50) on success, 'p' (=0x70) on failure.
+ */
+int pdc4030_cmd(ide_drive_t *drive, u8 cmd)
+{
+	u32 timeout;
+	u8 status_val;
+
+	promise_selectproc(drive);	/* redundant? */
+	HWIF(drive)->OUTB(0xF3, IDE_SECTOR_REG);
+	HWIF(drive)->OUTB(cmd, IDE_SELECT_REG);
+	HWIF(drive)->OUTB(PROMISE_EXTENDED_COMMAND, IDE_COMMAND_REG);
+	timeout = HZ * 10;
+	timeout += jiffies;
+	do {
+		if(time_after(jiffies, timeout)) {
+			return 2; /* device timed out */
+		}
+		/* Delays at least 10ms to give interface a chance */
+		mdelay(10);
+		status_val = HWIF(drive)->INB(IDE_SECTOR_REG);
+	} while (status_val != 0x50 && status_val != 0x70);
+
+	if(status_val == 0x50)
+		return 0; /* device returned success */
+	else
+		return 1; /* device returned failure */
+}
+
+/*
+ * pdc4030_identify sends a vendor-specific IDENTIFY command to the drive
+ */
+int pdc4030_identify(ide_drive_t *drive)
+{
+	return pdc4030_cmd(drive, PROMISE_IDENTIFY);
+}
+
+int enable_promise_support;
+
+/*
+ * setup_pdc4030()
+ * Completes the setup of a Promise DC4030 controller card, once found.
+ */
+int __init setup_pdc4030(ide_hwif_t *hwif)
+{
+        ide_drive_t *drive;
+	ide_hwif_t *hwif2;
+	struct dc_ident ident;
+	int i;
+	ide_startstop_t startstop;
+	
+	if (!hwif) return 0;
+
+	drive = &hwif->drives[0];
+	hwif2 = &ide_hwifs[hwif->index+1];
+	if (hwif->chipset == ide_pdc4030) /* we've already been found ! */
+		return 1;
+
+	if (hwif->INB(IDE_NSECTOR_REG) == 0xFF ||
+	    hwif->INB(IDE_SECTOR_REG) == 0xFF) {
+		return 0;
+	}
+	if (IDE_CONTROL_REG)
+		hwif->OUTB(0x08, IDE_CONTROL_REG);
+	if (pdc4030_cmd(drive,PROMISE_GET_CONFIG)) {
+		return 0;
+	}
+	if (ide_wait_stat(&startstop, drive,DATA_READY,BAD_W_STAT,WAIT_DRQ)) {
+		printk(KERN_INFO
+			"%s: Failed Promise read config!\n",hwif->name);
+		return 0;
+	}
+	hwif->ata_input_data(drive, &ident, SECTOR_WORDS);
+	if (ident.id[1] != 'P' || ident.id[0] != 'T') {
+		return 0;
+	}
+	printk(KERN_INFO "%s: Promise caching controller, ",hwif->name);
+	switch(ident.type) {
+		case 0x43:	printk("DC4030VL-2, "); break;
+		case 0x41:	printk("DC4030VL-1, "); break;
+		case 0x40:	printk("DC4030VL, "); break;
+		default:
+			printk("unknown - type 0x%02x - please report!\n"
+			       ,ident.type);
+			printk("Please e-mail the following data to "
+			       "promise@pnd-pc.demon.co.uk along with\n"
+			       "a description of your card and drives:\n");
+			for (i=0; i < 0x90; i++) {
+				printk("%02x ", ((unsigned char *)&ident)[i]);
+				if ((i & 0x0f) == 0x0f) printk("\n");
+			}
+			return 0;
+	}
+	printk("%dKB cache, ",(int)ident.cache_mem);
+	switch(ident.irq) {
+            case 0x00: hwif->irq = 14; break;
+            case 0x01: hwif->irq = 12; break;
+            default:   hwif->irq = 15; break;
+	}
+	printk("on IRQ %d\n",hwif->irq);
+
+	/*
+	 * Once found and identified, we set up the next hwif in the array
+	 * (hwif2 = ide_hwifs[hwif->index+1]) with the same io ports, irq
+	 * and other settings as the main hwif. This gives us two "mated"
+	 * hwifs pointing to the Promise card.
+	 *
+	 * We also have to shift the default values for the remaining
+	 * interfaces "up by one" to make room for the second interface on the
+	 * same set of values.
+	 */
+
+	hwif->chipset	= hwif2->chipset = ide_pdc4030;
+	hwif->mate	= hwif2;
+	hwif2->mate	= hwif;
+	hwif2->channel	= 1;
+	hwif->rqsize	= hwif2->rqsize = 127;
+	hwif->addressing = hwif2->addressing = 1;
+	hwif->selectproc = hwif2->selectproc = &promise_selectproc;
+	hwif->serialized = hwif2->serialized = 1;
+	/* DC4030 hosted drives need their own identify... */
+	hwif->identify = hwif2->identify = &pdc4030_identify;
+
+	/* Shift the remaining interfaces up by one */
+	for (i=MAX_HWIFS-1 ; i > hwif->index+1 ; i--) {
+		ide_hwif_t *h = &ide_hwifs[i];
+
+#ifdef DEBUG
+		printk(KERN_DEBUG "pdc4030: Shifting i/f %d values to i/f %d\n",i-1,i);
+#endif /* DEBUG */
+		ide_init_hwif_ports(&h->hw, (h-1)->io_ports[IDE_DATA_OFFSET], 0, NULL);
+		memcpy(h->io_ports, h->hw.io_ports, sizeof(h->io_ports));
+		h->noprobe = (h-1)->noprobe;
+	}
+	ide_init_hwif_ports(&hwif2->hw, hwif->io_ports[IDE_DATA_OFFSET], 0, NULL);
+	memcpy(hwif2->io_ports, hwif->hw.io_ports, sizeof(hwif2->io_ports));
+	hwif2->irq = hwif->irq;
+	hwif2->hw.irq = hwif->hw.irq = hwif->irq;
+	for (i=0; i<2 ; i++) {
+		hwif->drives[i].io_32bit = 3;
+		hwif2->drives[i].io_32bit = 3;
+		hwif->drives[i].keep_settings = 1;
+		hwif2->drives[i].keep_settings = 1;
+		if (!ident.current_tm[i].cyl)
+			hwif->drives[i].noprobe = 1;
+		if (!ident.current_tm[i+2].cyl)
+			hwif2->drives[i].noprobe = 1;
+	}
+	
+	/* Now override the normal ide disk read/write */
+	hwif->rw_disk = promise_rw_disk;
+	hwif2->rw_disk = promise_rw_disk;
+	
+#ifndef HWIF_PROBE_CLASSIC_METHOD
+	probe_hwif_init(&ide_hwifs[hwif->index]);
+	probe_hwif_init(&ide_hwifs[hwif2->index]);
+#endif /* HWIF_PROBE_CLASSIC_METHOD */
+
+        return 1;
+}
+
+/*
+ * detect_pdc4030()
+ * Tests for the presence of a DC4030 Promise card on this interface
+ * Returns: 1 if found, 0 if not found
+ */
+int __init detect_pdc4030(ide_hwif_t *hwif)
+{
+	ide_drive_t *drive = &hwif->drives[0];
+
+	if (IDE_DATA_REG == 0) { /* Skip test for non-existent interface */
+		return 0;
+	}
+	hwif->OUTB(0xF3, IDE_SECTOR_REG);
+	hwif->OUTB(0x14, IDE_SELECT_REG);
+	hwif->OUTB(PROMISE_EXTENDED_COMMAND, IDE_COMMAND_REG);
+	
+	ide_delay_50ms();
+
+	if (hwif->INB(IDE_ERROR_REG) == 'P' &&
+	    hwif->INB(IDE_NSECTOR_REG) == 'T' &&
+	    hwif->INB(IDE_SECTOR_REG) == 'I') {
+		return 1;
+	} else {
+		return 0;
+	}
+}
+
+
+#ifndef MODULE
+void __init ide_probe_for_pdc4030(void)
+#else
+int ide_probe_for_pdc4030(void)
+#endif
+{
+	unsigned int	index;
+	ide_hwif_t	*hwif;
+
+#ifndef MODULE
+	if (enable_promise_support == 0)
+		return;
+#endif
+
+	for (index = 0; index < MAX_HWIFS; index++) {
+		hwif = &ide_hwifs[index];
+		if (hwif->chipset == ide_unknown && detect_pdc4030(hwif)) {
+#ifndef MODULE
+			setup_pdc4030(hwif);
+#else
+			return setup_pdc4030(hwif);
+#endif
+		}
+	}
+#ifdef MODULE
+	return 0;
+#endif
+}
+
+void __init release_pdc4030(ide_hwif_t *hwif, ide_hwif_t *mate)
+{
+	hwif->chipset = ide_unknown;
+	hwif->selectproc = NULL;
+	hwif->serialized = 0;
+	hwif->drives[0].io_32bit = 0;
+	hwif->drives[1].io_32bit = 0;
+	hwif->drives[0].keep_settings = 0;
+	hwif->drives[1].keep_settings = 0;
+	hwif->drives[0].noprobe = 0;
+	hwif->drives[1].noprobe = 0;
+
+	if (mate != NULL) {
+		mate->chipset = ide_unknown;
+		mate->selectproc = NULL;
+		mate->serialized = 0;
+		mate->drives[0].io_32bit = 0;
+		mate->drives[1].io_32bit = 0;
+		mate->drives[0].keep_settings = 0;
+		mate->drives[1].keep_settings = 0;
+		mate->drives[0].noprobe = 0;
+		mate->drives[1].noprobe = 0;
+	}
+}
+
+#ifndef MODULE
+/*
+ * init_pdc4030:
+ *
+ * called by ide.c when parsing command line
+ */
+
+void __init init_pdc4030(void)
+{
+	enable_promise_support = 1;
+}
+
+#else
+
+MODULE_AUTHOR("Peter Denison");
+MODULE_DESCRIPTION("Support of Promise 4030 VLB series IDE chipsets");
+MODULE_LICENSE("GPL");
+
+int __init pdc4030_mod_init(void)
+{
+	if (enable_promise_support == 0)
+		enable_promise_support = 1;
+
+	if (!ide_probe_for_pdc4030())
+		return -ENODEV;
+        return 0;
+}
+module_init(pdc4030_mod_init);
+
+void __init pdc4030_mod_exit(void)
+{
+	unsigned int    index;
+	ide_hwif_t      *hwif;
+
+	if (enable_promise_support == 0)
+		return;
+ 
+	for (index = 0; index < MAX_HWIFS; index++) {
+		hwif = &ide_hwifs[index];
+		if (hwif->chipset == ide_pdc4030) {
+			ide_hwif_t *mate = &ide_hwifs[hwif->index+1];
+			if (mate->chipset == ide_pdc4030)
+				release_pdc4030(hwif, mate);
+			else
+				release_pdc4030(hwif, NULL);
+                }
+        }
+	enable_promise_support = 0;
+}
+module_exit(pdc4030_mod_exit);
+#endif
+
+/*
+ * promise_read_intr() is the handler for disk read/multread interrupts
+ */
+static ide_startstop_t promise_read_intr (ide_drive_t *drive)
+{
+	int total_remaining;
+	unsigned int sectors_left, sectors_avail, nsect;
+	struct request *rq;
+	ata_status_t status;
+#ifdef CONFIG_IDE_TASKFILE_IO
+	unsigned long flags;
+	char *to;
+#endif /* CONFIG_IDE_TASKFILE_IO */
+
+	status.all = HWIF(drive)->INB(IDE_STATUS_REG);
+	if (!OK_STAT(status.all, DATA_READY, BAD_R_STAT))
+		return DRIVER(drive)->error(drive,
+			"promise_read_intr", status.all);
+
+read_again:
+	do {
+		sectors_left = HWIF(drive)->INB(IDE_NSECTOR_REG);
+		HWIF(drive)->INB(IDE_SECTOR_REG);
+	} while (HWIF(drive)->INB(IDE_NSECTOR_REG) != sectors_left);
+	rq = HWGROUP(drive)->rq;
+	sectors_avail = rq->nr_sectors - sectors_left;
+	if (!sectors_avail)
+		goto read_again;
+
+read_next:
+	rq = HWGROUP(drive)->rq;
+	nsect = rq->current_nr_sectors;
+	if (nsect > sectors_avail)
+		nsect = sectors_avail;
+	sectors_avail -= nsect;
+#ifdef CONFIG_IDE_TASKFILE_IO
+	to = ide_map_buffer(rq, &flags);
+	HWIF(drive)->ata_input_data(drive, to, nsect * SECTOR_WORDS);
+#else /* !CONFIG_IDE_TASKFILE_IO */
+	HWIF(drive)->ata_input_data(drive, rq->buffer, nsect * SECTOR_WORDS);
+#endif /* CONFIG_IDE_TASKFILE_IO */
+
+#ifdef DEBUG_READ
+	printk(KERN_DEBUG "%s:  promise_read: sectors(%ld-%ld), "
+	       "buf=0x%08lx, rem=%ld\n", drive->name, rq->sector,
+	       rq->sector+nsect-1,
+#ifdef CONFIG_IDE_TASKFILE_IO
+		(unsigned long) to,
+#else /* !CONFIG_IDE_TASKFILE_IO */
+		(unsigned long) rq->buffer,
+#endif /* CONFIG_IDE_TASKFILE_IO */
+	       rq->nr_sectors-nsect);
+#endif /* DEBUG_READ */
+
+#ifdef CONFIG_IDE_TASKFILE_IO
+	ide_unmap_buffer(to, &flags);
+#else /* !CONFIG_IDE_TASKFILE_IO */
+	rq->buffer += nsect<<9;
+#endif /* CONFIG_IDE_TASKFILE_IO */
+	rq->sector += nsect;
+	rq->errors = 0;
+	rq->nr_sectors -= nsect;
+	total_remaining = rq->nr_sectors;
+	if ((rq->current_nr_sectors -= nsect) <= 0) {
+		DRIVER(drive)->end_request(drive, 1);
+	}
+/*
+ * Now the data has been read in, do the following:
+ * 
+ * if there are still sectors left in the request, 
+ *   if we know there are still sectors available from the interface,
+ *     go back and read the next bit of the request.
+ *   else if DRQ is asserted, there are more sectors available, so
+ *     go back and find out how many, then read them in.
+ *   else if BUSY is asserted, we are going to get an interrupt, so
+ *     set the handler for the interrupt and just return
+ */
+	if (total_remaining > 0) {
+		if (sectors_avail)
+			goto read_next;
+		status.all = HWIF(drive)->INB(IDE_STATUS_REG);
+		if (status.b.drq)
+			goto read_again;
+		if (status.b.bsy) {
+			if (HWGROUP(drive)->handler != NULL)
+				BUG();
+			ide_set_handler(drive,
+					&promise_read_intr,
+					WAIT_CMD,
+					NULL);
+#ifdef DEBUG_READ
+			printk(KERN_DEBUG "%s: promise_read: waiting for"
+			       "interrupt\n", drive->name);
+#endif /* DEBUG_READ */
+			return ide_started;
+		}
+		printk(KERN_ERR "%s: Eeek! promise_read_intr: sectors left "
+		       "!DRQ !BUSY\n", drive->name);
+		return DRIVER(drive)->error(drive,
+				"promise read intr", status.all);
+	}
+	return ide_stopped;
+}
+
+/*
+ * promise_complete_pollfunc()
+ * This is the polling function for waiting (nicely!) until drive stops
+ * being busy. It is invoked at the end of a write, after the previous poll
+ * has finished.
+ *
+ * Once not busy, the end request is called.
+ */
+static ide_startstop_t promise_complete_pollfunc(ide_drive_t *drive)
+{
+	ide_hwgroup_t *hwgroup = HWGROUP(drive);
+	struct request *rq = hwgroup->rq;
+	int i;
+
+	if ((HWIF(drive)->INB(IDE_STATUS_REG)) & BUSY_STAT) {
+		if (time_before(jiffies, hwgroup->poll_timeout)) {
+			if (hwgroup->handler != NULL)
+				BUG();
+			ide_set_handler(drive,
+					&promise_complete_pollfunc,
+					HZ/100,
+					NULL);
+			return ide_started; /* continue polling... */
+		}
+		hwgroup->poll_timeout = 0;
+		printk(KERN_ERR "%s: completion timeout - still busy!\n",
+		       drive->name);
+		return DRIVER(drive)->error(drive, "busy timeout",
+				HWIF(drive)->INB(IDE_STATUS_REG));
+	}
+
+	hwgroup->poll_timeout = 0;
+#ifdef DEBUG_WRITE
+	printk(KERN_DEBUG "%s: Write complete - end_request\n", drive->name);
+#endif /* DEBUG_WRITE */
+	for (i = rq->nr_sectors; i > 0; ) {
+		i -= rq->current_nr_sectors;
+		DRIVER(drive)->end_request(drive, 1);
+	}
+	return ide_stopped;
+}
+
+/*
+ * promise_multwrite() transfers a block of up to mcount sectors of data
+ * to a drive as part of a disk multiple-sector write operation.
+ *
+ * Returns 0 on success.
+ *
+ * Note that we may be called from two contexts - the do_rw_disk context
+ * and IRQ context. The IRQ can happen any time after we've output the
+ * full "mcount" number of sectors, so we must make sure we update the
+ * state _before_ we output the final part of the data!
+ */
+int promise_multwrite (ide_drive_t *drive, unsigned int mcount)
+{
+	ide_hwgroup_t *hwgroup	= HWGROUP(drive);
+	struct request *rq	= &hwgroup->wrq;
+
+	do {
+		char *buffer;
+		int nsect = rq->current_nr_sectors;
+#ifdef CONFIG_IDE_TASKFILE_IO
+		unsigned long flags;
+#endif /* CONFIG_IDE_TASKFILE_IO */
+
+		if (nsect > mcount)
+			nsect = mcount;
+		mcount -= nsect;
+#ifdef CONFIG_IDE_TASKFILE_IO
+		buffer = ide_map_buffer(rq, &flags);
+		rq->sector += nsect;
+#else /* !CONFIG_IDE_TASKFILE_IO */
+		buffer = rq->buffer;
+
+		rq->sector += nsect;
+		rq->buffer += nsect << 9;
+#endif /* CONFIG_IDE_TASKFILE_IO */
+		rq->nr_sectors -= nsect;
+		rq->current_nr_sectors -= nsect;
+
+		/* Do we move to the next bh after this? */
+		if (!rq->current_nr_sectors) {
+			struct buffer_head *bh = rq->bh->b_reqnext;
+
+			/* end early early we ran out of requests */
+			if (!bh) {
+				mcount = 0;
+			} else {
+				rq->bh			= bh;
+				rq->current_nr_sectors	= bh->b_size >> 9;
+				rq->hard_cur_sectors = rq->current_nr_sectors;
+				rq->buffer		= bh->b_data;
+			}
+		}
+
+		/*
+		 * Ok, we're all setup for the interrupt
+		 * re-entering us on the last transfer.
+		 */
+		taskfile_output_data(drive, buffer, nsect<<7);
+#ifdef CONFIG_IDE_TASKFILE_IO
+		ide_unmap_buffer(buffer, &flags);
+#endif /* CONFIG_IDE_TASKFILE_IO */
+	} while (mcount);
+
+	return 0;
+}
+
+/*
+ * promise_write_pollfunc() is the handler for disk write completion polling.
+ */
+static ide_startstop_t promise_write_pollfunc (ide_drive_t *drive)
+{
+	ide_hwgroup_t *hwgroup = HWGROUP(drive);
+
+	if (HWIF(drive)->INB(IDE_NSECTOR_REG) != 0) {
+		if (time_before(jiffies, hwgroup->poll_timeout)) {
+			if (hwgroup->handler != NULL)
+				BUG();
+			ide_set_handler(drive,
+					&promise_write_pollfunc,
+					HZ/100,
+					NULL);
+			return ide_started; /* continue polling... */
+		}
+		hwgroup->poll_timeout = 0;
+		printk(KERN_ERR "%s: write timed-out!\n",drive->name);
+		return DRIVER(drive)->error(drive, "write timeout",
+				HWIF(drive)->INB(IDE_STATUS_REG));
+	}
+
+	/*
+	 * Now write out last 4 sectors and poll for not BUSY
+	 */
+	promise_multwrite(drive, 4);
+	hwgroup->poll_timeout = jiffies + WAIT_WORSTCASE;
+	if (hwgroup->handler != NULL)
+		BUG();
+	ide_set_handler(drive, &promise_complete_pollfunc, HZ/100, NULL);
+#ifdef DEBUG_WRITE
+	printk(KERN_DEBUG "%s: Done last 4 sectors - status = %02x\n",
+		drive->name, HWIF(drive)->INB(IDE_STATUS_REG));
+#endif /* DEBUG_WRITE */
+	return ide_started;
+}
+
+/*
+ * promise_write() transfers a block of one or more sectors of data to a
+ * drive as part of a disk write operation. All but 4 sectors are transferred
+ * in the first attempt, then the interface is polled (nicely!) for completion
+ * before the final 4 sectors are transferred. There is no interrupt generated
+ * on writes (at least on the DC4030VL-2), we just have to poll for NOT BUSY.
+ */
+static ide_startstop_t promise_write (ide_drive_t *drive)
+{
+	ide_hwgroup_t *hwgroup = HWGROUP(drive);
+	struct request *rq = &hwgroup->wrq;
+
+#ifdef DEBUG_WRITE
+	printk(KERN_DEBUG "%s: promise_write: sectors(%ld-%ld), "
+	       "buffer=%p\n", drive->name, rq->sector,
+	       rq->sector + rq->nr_sectors - 1, rq->buffer);
+#endif /* DEBUG_WRITE */
+
+	/*
+	 * If there are more than 4 sectors to transfer, do n-4 then go into
+	 * the polling strategy as defined above.
+	 */
+	if (rq->nr_sectors > 4) {
+		if (promise_multwrite(drive, rq->nr_sectors - 4))
+			return ide_stopped;
+		hwgroup->poll_timeout = jiffies + WAIT_WORSTCASE;
+		if (hwgroup->handler != NULL)	/* paranoia check */
+			BUG();
+		ide_set_handler (drive, &promise_write_pollfunc, HZ/100, NULL);
+		return ide_started;
+	} else {
+	/*
+	 * There are 4 or fewer sectors to transfer, do them all in one go
+	 * and wait for NOT BUSY.
+	 */
+		if (promise_multwrite(drive, rq->nr_sectors))
+			return ide_stopped;
+		hwgroup->poll_timeout = jiffies + WAIT_WORSTCASE;
+		if (hwgroup->handler != NULL)
+			BUG();
+		ide_set_handler(drive,
+				&promise_complete_pollfunc,
+				HZ/100,
+				NULL);
+
+#ifdef DEBUG_WRITE
+		printk(KERN_DEBUG "%s: promise_write: <= 4 sectors, "
+			"status = %02x\n", drive->name,
+			HWIF(drive)->INB(IDE_STATUS_REG));
+#endif /* DEBUG_WRITE */
+		return ide_started;
+	}
+}
+
+/*
+ * do_pdc4030_io() is called from promise_rw_disk, having had the block number
+ * already set up. It issues a READ or WRITE command to the Promise
+ * controller, assuming LBA has been used to set up the block number.
+ */
+#ifndef CONFIG_IDE_TASKFILE_IO
+ide_startstop_t do_pdc4030_io (ide_drive_t *drive, struct request *rq)
+{
+#else /* CONFIG_IDE_TASKFILE_IO */
+ide_startstop_t do_pdc4030_io (ide_drive_t *drive, ide_task_t *task)
+{
+	struct request *rq	= HWGROUP(drive)->rq;
+	task_struct_t *taskfile = (task_struct_t *) task->tfRegister;
+#endif /* CONFIG_IDE_TASKFILE_IO */
+	ide_startstop_t startstop;
+	unsigned long timeout;
+	u8 stat = 0;
+
+#ifdef CONFIG_IDE_TASKFILE_IO
+	if (IDE_CONTROL_REG)
+		HWIF(drive)->OUTB(drive->ctl, IDE_CONTROL_REG);	/* clear nIEN */
+	SELECT_MASK(drive, 0);
+	HWIF(drive)->OUTB(taskfile->feature, IDE_FEATURE_REG);
+	HWIF(drive)->OUTB(taskfile->sector_count, IDE_NSECTOR_REG);
+	/* refers to number of sectors to transfer */
+	HWIF(drive)->OUTB(taskfile->sector_number, IDE_SECTOR_REG);
+	/* refers to sector offset or start sector */
+	HWIF(drive)->OUTB(taskfile->low_cylinder, IDE_LCYL_REG);
+	HWIF(drive)->OUTB(taskfile->high_cylinder, IDE_HCYL_REG);
+	HWIF(drive)->OUTB(taskfile->device_head, IDE_SELECT_REG);
+	HWIF(drive)->OUTB(taskfile->command, IDE_COMMAND_REG);
+#endif /* CONFIG_IDE_TASKFILE_IO */
+
+	switch(rq->cmd) {
+	case READ:
+#ifndef CONFIG_IDE_TASKFILE_IO
+		HWIF(drive)->OUTB(PROMISE_READ, IDE_COMMAND_REG);
+#endif /* CONFIG_IDE_TASKFILE_IO */
+/*
+ * The card's behaviour is odd at this point. If the data is
+ * available, DRQ will be true, and no interrupt will be
+ * generated by the card. If this is the case, we need to call the 
+ * "interrupt" handler (promise_read_intr) directly. Otherwise, if
+ * an interrupt is going to occur, bit0 of the SELECT register will
+ * be high, so we can set the handler the just return and be interrupted.
+ * If neither of these is the case, we wait for up to 50ms (badly I'm
+ * afraid!) until one of them is.
+ */
+		timeout = jiffies + HZ/20; /* 50ms wait */
+		do {
+			stat = HWIF(drive)->INB(IDE_STATUS_REG);
+			if (stat & DRQ_STAT) {
+				udelay(1);
+				return promise_read_intr(drive);
+			}
+			if (HWIF(drive)->INB(IDE_SELECT_REG) & 0x01) {
+#ifdef DEBUG_READ
+				printk(KERN_DEBUG "%s: read: waiting for "
+						"interrupt\n", drive->name);
+#endif /* DEBUG_READ */
+				ide_set_handler(drive,
+						&promise_read_intr,
+						WAIT_CMD,
+						NULL);
+				return ide_started;
+			}
+			udelay(1);
+		} while (time_before(jiffies, timeout));
+
+		printk(KERN_ERR "%s: reading: No DRQ and not "
+				"waiting - Odd!\n", drive->name);
+		return ide_stopped;
+	case WRITE:
+#ifndef CONFIG_IDE_TASKFILE_IO
+		HWIF(drive)->OUTB(PROMISE_WRITE, IDE_COMMAND_REG);
+#endif /* CONFIG_IDE_TASKFILE_IO */
+		if (ide_wait_stat(&startstop, drive, DATA_READY,
+				drive->bad_wstat, WAIT_DRQ)) {
+			printk(KERN_ERR "%s: no DRQ after issuing "
+				"PROMISE_WRITE\n", drive->name);
+			return startstop;
+	    	}
+		if (!drive->unmask)
+			local_irq_disable();
+		HWGROUP(drive)->wrq = *rq; /* scratchpad */
+		return promise_write(drive);
+	default:
+		printk("KERN_WARNING %s: bad command: %d\n",
+			drive->name, rq->cmd);
+		DRIVER(drive)->end_request(drive, 0);
+		return ide_stopped;
+	}
+}
+
+static ide_startstop_t promise_rw_disk (ide_drive_t *drive, struct request *rq, unsigned long block)
+{
+	/* The four drives on the two logical (one physical) interfaces
+	   are distinguished by writing the drive number (0-3) to the
+	   Feature register.
+	   FIXME: Is promise_selectproc now redundant??
+	*/
+	int drive_number = (HWIF(drive)->channel << 1) + drive->select.b.unit;
+#ifndef CONFIG_IDE_TASKFILE_IO
+	ide_hwif_t *hwif = HWIF(drive);
+
+	BUG_ON(rq->nr_sectors > 127);
+
+	if (IDE_CONTROL_REG)
+		hwif->OUTB(drive->ctl, IDE_CONTROL_REG);
+
+#ifdef DEBUG
+	printk("%s: %sing: LBAsect=%ld, sectors=%ld, "
+		"buffer=0x%08lx\n", drive->name,
+		(rq->cmd==READ)?"read":"writ", block,
+		rq->nr_sectors, (unsigned long) rq->buffer);
+#endif
+	hwif->OUTB(drive_number, IDE_FEATURE_REG);
+	hwif->OUTB(rq->nr_sectors, IDE_NSECTOR_REG);
+	hwif->OUTB(block,IDE_SECTOR_REG);
+	hwif->OUTB(block>>=8,IDE_LCYL_REG);
+	hwif->OUTB(block>>=8,IDE_HCYL_REG);
+	hwif->OUTB(((block>>8)&0x0f)|drive->select.all,IDE_SELECT_REG);
+
+	return do_pdc4030_io(drive, rq);
+
+#else /* CONFIG_IDE_TASKFILE_IO */
+
+	struct hd_drive_task_hdr	taskfile;
+	ide_task_t			args;
+
+	memset(&taskfile, 0, sizeof(struct hd_drive_task_hdr));
+
+	taskfile.feature	= drive_number;
+	taskfile.sector_count	= rq->nr_sectors;
+	taskfile.sector_number	= block;
+	taskfile.low_cylinder	= (block>>=8);
+	taskfile.high_cylinder	= (block>>=8);
+	taskfile.device_head	= ((block>>8)&0x0f)|drive->select.all;
+	taskfile.command	= (rq->cmd==READ)?PROMISE_READ:PROMISE_WRITE;
+
+	memcpy(args.tfRegister, &taskfile, sizeof(struct hd_drive_task_hdr));
+	memset(args.hobRegister, 0, sizeof(struct hd_drive_hob_hdr));
+	/* We can't call ide_cmd_type_parser here, since it won't understand
+	   our command, but that doesn't matter, since we don't use the
+	   generic interrupt handlers either. Setup the bits of args that we
+	   do need.
+	*/
+	args.handler		= NULL;
+	args.rq			= (struct request *) rq;
+	rq->special		= (ide_task_t *)&args;
+
+	return do_pdc4030_io(drive, &args);
+#endif /* CONFIG_IDE_TASKFILE_IO */
+}
FUNET's LINUX-ADM group, linux-adm@nic.funet.fi
TCL-scripts by Sam Shen (who was at: slshen@lbl.gov)