diff options
Diffstat (limited to 'drivers/ide/ide-timing.h')
-rw-r--r-- | drivers/ide/ide-timing.h | 281 |
1 files changed, 281 insertions, 0 deletions
diff --git a/drivers/ide/ide-timing.h b/drivers/ide/ide-timing.h new file mode 100644 index 000000000000..c1196ce15b4d --- /dev/null +++ b/drivers/ide/ide-timing.h @@ -0,0 +1,281 @@ +#ifndef _IDE_TIMING_H +#define _IDE_TIMING_H + +/* + * $Id: ide-timing.h,v 1.6 2001/12/23 22:47:56 vojtech Exp $ + * + * Copyright (c) 1999-2001 Vojtech Pavlik + */ + +/* + * 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@ucw.cz>, or by paper mail: + * Vojtech Pavlik, Simunkova 1594, Prague 8, 182 00 Czech Republic + */ + +#include <linux/hdreg.h> + +#define XFER_PIO_5 0x0d +#define XFER_UDMA_SLOW 0x4f + +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 0-6 timings (in nanoseconds). + * These were taken from ATA/ATAPI-6 standard, rev 0a, except + * for PIO 5, which is a nonstandard extension and UDMA6, which + * is currently supported only by Maxtor drives. + */ + +static struct ide_timing ide_timing[] = { + + { XFER_UDMA_6, 0, 0, 0, 0, 0, 0, 0, 15 }, + { 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_133 0x48 +#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_133) == XFER_UDMA_133) + if ((best = (id->dma_ultra & 0x0040) ? XFER_UDMA_6 : 0)) return best; + + 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 * 1000, T); + q->act8b = EZ(t->act8b * 1000, T); + q->rec8b = EZ(t->rec8b * 1000, T); + q->cyc8b = EZ(t->cyc8b * 1000, T); + q->active = EZ(t->active * 1000, T); + q->recover = EZ(t->recover * 1000, T); + q->cycle = EZ(t->cycle * 1000, T); + q->udma = EZ(t->udma * 1000, 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 |