patch-2.4.2 linux/drivers/ide/ide-timing.h

• Lines: 280
• Date: Sat Feb 3 11:27:43 2001
• Orig file: v2.4.1/linux/drivers/ide/ide-timing.h
• Orig date: Wed Dec 31 16:00:00 1969

diff -u --recursive --new-file v2.4.1/linux/drivers/ide/ide-timing.h linux/drivers/ide/ide-timing.h
@@ -0,0 +1,279 @@
+#ifndef _IDE_TIMING_H
+#define _IDE_TIMING_H
+
+/*
+ * $Id: ide-timing.h,v 1.5 2001/01/15 21:48:56 vojtech Exp $
+ *
+ *  Copyright (c) 1999-2000 Vojtech Pavlik
+ *
+ *  Sponsored by SuSE
+ */
+
+/*
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ *
+ * Should you need to contact me, the author, you can do so either by
+ * e-mail - mail your message to <vojtech@suse.cz>, or by paper mail:
+ * Vojtech Pavlik, Ucitelska 1576, Prague 8, 182 00 Czech Republic
+ */
+
+#include <linux/hdreg.h>
+
+#ifndef XFER_PIO_5
+#define XFER_PIO_5		0x0d
+#define XFER_UDMA_SLOW		0x4f
+#endif
+
+struct ide_timing {
+	short mode;
+	short setup;	/* t1 */
+	short act8b;	/* t2 for 8-bit io */
+	short rec8b;	/* t2i for 8-bit io */
+	short cyc8b;	/* t0 for 8-bit io */
+	short active;	/* t2 or tD */
+	short recover;	/* t2i or tK */
+	short cycle;	/* t0 */
+	short udma;	/* t2CYCTYP/2 */
+};
+
+/*
+ * PIO 0-5, MWDMA 0-2 and UDMA 0-5 timings (in nanoseconds).
+ * These were taken from ATA/ATAPI-6 standard, rev 0a, except
+ * for PIO 5, which is a nonstandard extension.
+ */
+
+static struct ide_timing ide_timing[] = {
+
+	{ XFER_UDMA_5,     0,   0,   0,   0,   0,   0,   0,  20 },
+	{ XFER_UDMA_4,     0,   0,   0,   0,   0,   0,   0,  30 },
+	{ XFER_UDMA_3,     0,   0,   0,   0,   0,   0,   0,  45 },
+
+	{ XFER_UDMA_2,     0,   0,   0,   0,   0,   0,   0,  60 },
+	{ XFER_UDMA_1,     0,   0,   0,   0,   0,   0,   0,  80 },
+	{ XFER_UDMA_0,     0,   0,   0,   0,   0,   0,   0, 120 },
+
+	{ XFER_UDMA_SLOW,  0,   0,   0,   0,   0,   0,   0, 150 },
+                                          
+	{ XFER_MW_DMA_2,  25,   0,   0,   0,  70,  25, 120,   0 },
+	{ XFER_MW_DMA_1,  45,   0,   0,   0,  80,  50, 150,   0 },
+	{ XFER_MW_DMA_0,  60,   0,   0,   0, 215, 215, 480,   0 },
+                                          
+	{ XFER_SW_DMA_2,  60,   0,   0,   0, 120, 120, 240,   0 },
+	{ XFER_SW_DMA_1,  90,   0,   0,   0, 240, 240, 480,   0 },
+	{ XFER_SW_DMA_0, 120,   0,   0,   0, 480, 480, 960,   0 },
+
+	{ XFER_PIO_5,     20,  50,  30, 100,  50,  30, 100,   0 },
+	{ XFER_PIO_4,     25,  70,  25, 120,  70,  25, 120,   0 },
+	{ XFER_PIO_3,     30,  80,  70, 180,  80,  70, 180,   0 },
+
+	{ XFER_PIO_2,     30, 290,  40, 330, 100,  90, 240,   0 },
+	{ XFER_PIO_1,     50, 290,  93, 383, 125, 100, 383,   0 },
+	{ XFER_PIO_0,     70, 290, 240, 600, 165, 150, 600,   0 },
+
+	{ XFER_PIO_SLOW, 120, 290, 240, 960, 290, 240, 960,   0 },
+
+	{ -1 }
+};
+
+#define IDE_TIMING_SETUP	0x01
+#define IDE_TIMING_ACT8B	0x02
+#define IDE_TIMING_REC8B	0x04
+#define IDE_TIMING_CYC8B	0x08
+#define IDE_TIMING_8BIT		0x0e
+#define IDE_TIMING_ACTIVE	0x10
+#define IDE_TIMING_RECOVER	0x20
+#define IDE_TIMING_CYCLE	0x40
+#define IDE_TIMING_UDMA		0x80
+#define IDE_TIMING_ALL		0xff
+
+#define MIN(a,b)	((a)<(b)?(a):(b))
+#define MAX(a,b)	((a)>(b)?(a):(b))
+#define FIT(v,min,max)	MAX(MIN(v,max),min)
+#define ENOUGH(v,unit)	(((v)-1)/(unit)+1)
+#define EZ(v,unit)	((v)?ENOUGH(v,unit):0)
+
+#define XFER_MODE	0xf0
+#define XFER_UDMA_100	0x44
+#define XFER_UDMA_66	0x42
+#define XFER_UDMA	0x40
+#define XFER_MWDMA	0x20
+#define XFER_SWDMA	0x10
+#define XFER_EPIO	0x01
+#define XFER_PIO	0x00
+
+static short ide_find_best_mode(ide_drive_t *drive, int map)
+{
+	struct hd_driveid *id = drive->id;
+	short best = 0;
+
+	if (!id)
+		return XFER_PIO_SLOW;
+
+	if ((map & XFER_UDMA) && (id->field_valid & 4)) {	/* Want UDMA and UDMA bitmap valid */
+
+		if ((map & XFER_UDMA_100) == XFER_UDMA_100)
+			if ((best = (id->dma_ultra & 0x0020) ? XFER_UDMA_5 : 0)) return best;
+
+		if ((map & XFER_UDMA_66) == XFER_UDMA_66)
+			if ((best = (id->dma_ultra & 0x0010) ? XFER_UDMA_4 :
+                	    	    (id->dma_ultra & 0x0008) ? XFER_UDMA_3 : 0)) return best;
+
+                if ((best = (id->dma_ultra & 0x0004) ? XFER_UDMA_2 :
+                	    (id->dma_ultra & 0x0002) ? XFER_UDMA_1 :
+                	    (id->dma_ultra & 0x0001) ? XFER_UDMA_0 : 0)) return best;
+	}
+
+	if ((map & XFER_MWDMA) && (id->field_valid & 2)) {	/* Want MWDMA and drive has EIDE fields */
+
+		if ((best = (id->dma_mword & 0x0004) ? XFER_MW_DMA_2 :
+                	    (id->dma_mword & 0x0002) ? XFER_MW_DMA_1 :
+                	    (id->dma_mword & 0x0001) ? XFER_MW_DMA_0 : 0)) return best;
+	}
+
+	if (map & XFER_SWDMA) {					/* Want SWDMA */
+
+ 		if (id->field_valid & 2) {			/* EIDE SWDMA */
+
+			if ((best = (id->dma_1word & 0x0004) ? XFER_SW_DMA_2 :
+      				    (id->dma_1word & 0x0002) ? XFER_SW_DMA_1 :
+				    (id->dma_1word & 0x0001) ? XFER_SW_DMA_0 : 0)) return best;
+		}
+
+		if (id->capability & 1) {			/* Pre-EIDE style SWDMA */
+
+			if ((best = (id->tDMA == 2) ? XFER_SW_DMA_2 :
+				    (id->tDMA == 1) ? XFER_SW_DMA_1 :
+				    (id->tDMA == 0) ? XFER_SW_DMA_0 : 0)) return best;
+		}
+	}
+
+
+	if ((map & XFER_EPIO) && (id->field_valid & 2)) {	/* EIDE PIO modes */
+
+		if ((best = (drive->id->eide_pio_modes & 4) ? XFER_PIO_5 :
+			    (drive->id->eide_pio_modes & 2) ? XFER_PIO_4 :
+			    (drive->id->eide_pio_modes & 1) ? XFER_PIO_3 : 0)) return best;
+	}
+	
+	return  (drive->id->tPIO == 2) ? XFER_PIO_2 :
+		(drive->id->tPIO == 1) ? XFER_PIO_1 :
+		(drive->id->tPIO == 0) ? XFER_PIO_0 : XFER_PIO_SLOW;
+}
+
+static void ide_timing_quantize(struct ide_timing *t, struct ide_timing *q, int T, int UT)
+{
+	q->setup   = EZ(t->setup,   T);
+	q->act8b   = EZ(t->act8b,   T);
+	q->rec8b   = EZ(t->rec8b,   T);
+	q->cyc8b   = EZ(t->cyc8b,   T);
+	q->active  = EZ(t->active,  T);
+	q->recover = EZ(t->recover, T);
+	q->cycle   = EZ(t->cycle,   T);
+	q->udma    = EZ(t->udma,   UT);
+}
+
+static void ide_timing_merge(struct ide_timing *a, struct ide_timing *b, struct ide_timing *m, unsigned int what)
+{
+	if (what & IDE_TIMING_SETUP  ) m->setup   = MAX(a->setup,   b->setup);
+	if (what & IDE_TIMING_ACT8B  ) m->act8b   = MAX(a->act8b,   b->act8b);
+	if (what & IDE_TIMING_REC8B  ) m->rec8b   = MAX(a->rec8b,   b->rec8b);
+	if (what & IDE_TIMING_CYC8B  ) m->cyc8b   = MAX(a->cyc8b,   b->cyc8b);
+	if (what & IDE_TIMING_ACTIVE ) m->active  = MAX(a->active,  b->active);
+	if (what & IDE_TIMING_RECOVER) m->recover = MAX(a->recover, b->recover);
+	if (what & IDE_TIMING_CYCLE  ) m->cycle   = MAX(a->cycle,   b->cycle);
+	if (what & IDE_TIMING_UDMA   ) m->udma    = MAX(a->udma,    b->udma);
+}
+
+static struct ide_timing* ide_timing_find_mode(short speed)
+{
+	struct ide_timing *t;
+
+	for (t = ide_timing; t->mode != speed; t++)
+		if (t->mode < 0)
+			return NULL;
+	return t; 
+}
+
+static int ide_timing_compute(ide_drive_t *drive, short speed, struct ide_timing *t, int T, int UT)
+{
+	struct hd_driveid *id = drive->id;
+	struct ide_timing *s, p;
+
+/*
+ * Find the mode.
+ */
+
+	if (!(s = ide_timing_find_mode(speed)))
+		return -EINVAL;
+
+/*
+ * If the drive is an EIDE drive, it can tell us it needs extended
+ * PIO/MWDMA cycle timing.
+ */
+
+	if (id && id->field_valid & 2) {	/* EIDE drive */
+
+		memset(&p, 0, sizeof(p));
+
+		switch (speed & XFER_MODE) {
+
+			case XFER_PIO:
+				if (speed <= XFER_PIO_2) p.cycle = p.cyc8b = id->eide_pio;
+						    else p.cycle = p.cyc8b = id->eide_pio_iordy;
+				break;
+
+			case XFER_MWDMA:
+				p.cycle = id->eide_dma_min;
+				break;
+		}
+
+		ide_timing_merge(&p, t, t, IDE_TIMING_CYCLE | IDE_TIMING_CYC8B);
+	}
+
+/*
+ * Convert the timing to bus clock counts.
+ */
+
+	ide_timing_quantize(s, t, T, UT);
+
+/*
+ * Even in DMA/UDMA modes we still use PIO access for IDENTIFY, S.M.A.R.T
+ * and some other commands. We have to ensure that the DMA cycle timing is
+ * slower/equal than the fastest PIO timing.
+ */
+
+	if ((speed & XFER_MODE) != XFER_PIO) {
+		ide_timing_compute(drive, ide_find_best_mode(drive, XFER_PIO | XFER_EPIO), &p, T, UT);
+		ide_timing_merge(&p, t, t, IDE_TIMING_ALL);
+	}
+
+/*
+ * Lenghten active & recovery time so that cycle time is correct.
+ */
+
+	if (t->act8b + t->rec8b < t->cyc8b) {
+		t->act8b += (t->cyc8b - (t->act8b + t->rec8b)) / 2;
+		t->rec8b = t->cyc8b - t->act8b;
+	}
+
+	if (t->active + t->recover < t->cycle) {
+		t->active += (t->cycle - (t->active + t->recover)) / 2;
+		t->recover = t->cycle - t->active;
+	}
+
+	return 0;
+}
+
+#endif