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Release 4.14 drivers/ide/ide-timings.c

Directory: drivers/ide
/*
 *  Copyright (c) 1999-2001 Vojtech Pavlik
 *  Copyright (c) 2007-2008 Bartlomiej Zolnierkiewicz
 *
 * 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/kernel.h>
#include <linux/ide.h>
#include <linux/module.h>

/*
 * 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_MW_DMA_4,  25,   0,   0,   0,  55,  20,  80,   0 },
	{ XFER_MW_DMA_3,  25,   0,   0,   0,  65,  25, 100,   0 },
	{ 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_6,     10,  55,  20,  80,  55,  20,  80,   0 },
	{ XFER_PIO_5,     15,  65,  25, 100,  65,  25, 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 },

	{ 0xff }
};


struct ide_timing *ide_timing_find_mode(u8 speed) { struct ide_timing *t; for (t = ide_timing; t->mode != speed; t++) if (t->mode == 0xff) return NULL; return t; }

Contributors

PersonTokensPropCommitsCommitProp
Bartlomiej Zolnierkiewicz44100.00%1100.00%
Total44100.00%1100.00%

EXPORT_SYMBOL_GPL(ide_timing_find_mode);
u16 ide_pio_cycle_time(ide_drive_t *drive, u8 pio) { u16 *id = drive->id; struct ide_timing *t = ide_timing_find_mode(XFER_PIO_0 + pio); u16 cycle = 0; if (id[ATA_ID_FIELD_VALID] & 2) { if (ata_id_has_iordy(drive->id)) cycle = id[ATA_ID_EIDE_PIO_IORDY]; else cycle = id[ATA_ID_EIDE_PIO]; /* conservative "downgrade" for all pre-ATA2 drives */ if (pio < 3 && cycle < t->cycle) cycle = 0; /* use standard timing */ /* Use the standard timing for the CF specific modes too */ if (pio > 4 && ata_id_is_cfa(id)) cycle = 0; } return cycle ? cycle : t->cycle; }

Contributors

PersonTokensPropCommitsCommitProp
Bartlomiej Zolnierkiewicz9986.09%375.00%
Sergei Shtylyov1613.91%125.00%
Total115100.00%4100.00%

EXPORT_SYMBOL_GPL(ide_pio_cycle_time); #define ENOUGH(v, unit) (((v) - 1) / (unit) + 1) #define EZ(v, unit) ((v) ? ENOUGH((v) * 1000, unit) : 0)
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); }

Contributors

PersonTokensPropCommitsCommitProp
Jens Axboe126100.00%1100.00%
Total126100.00%1100.00%


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); }

Contributors

PersonTokensPropCommitsCommitProp
Jens Axboe18495.83%150.00%
Clemens Buchacher84.17%150.00%
Total192100.00%2100.00%

EXPORT_SYMBOL_GPL(ide_timing_merge);
int ide_timing_compute(ide_drive_t *drive, u8 speed, struct ide_timing *t, int T, int UT) { u16 *id = drive->id; struct ide_timing *s, p; /* * Find the mode. */ s = ide_timing_find_mode(speed); if (s == NULL) return -EINVAL; /* * Copy the timing from the table. */ *t = *s; /* * If the drive is an EIDE drive, it can tell us it needs extended * PIO/MWDMA cycle timing. */ if (id[ATA_ID_FIELD_VALID] & 2) { /* EIDE drive */ memset(&p, 0, sizeof(p)); if (speed >= XFER_PIO_0 && speed < XFER_SW_DMA_0) { if (speed <= XFER_PIO_2) p.cycle = p.cyc8b = id[ATA_ID_EIDE_PIO]; else if ((speed <= XFER_PIO_4) || (speed == XFER_PIO_5 && !ata_id_is_cfa(id))) p.cycle = p.cyc8b = id[ATA_ID_EIDE_PIO_IORDY]; } else if (speed >= XFER_MW_DMA_0 && speed <= XFER_MW_DMA_2) p.cycle = id[ATA_ID_EIDE_DMA_MIN]; ide_timing_merge(&p, t, t, IDE_TIMING_CYCLE | IDE_TIMING_CYC8B); } /* * Convert the timing to bus clock counts. */ ide_timing_quantize(t, 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 current PIO timing. */ if (speed >= XFER_SW_DMA_0) { ide_timing_compute(drive, drive->pio_mode, &p, T, UT); ide_timing_merge(&p, t, t, IDE_TIMING_ALL); } /* * Lengthen 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; }

Contributors

PersonTokensPropCommitsCommitProp
Jens Axboe25775.37%19.09%
Bartlomiej Zolnierkiewicz6318.48%872.73%
Sergei Shtylyov216.16%218.18%
Total341100.00%11100.00%

EXPORT_SYMBOL_GPL(ide_timing_compute);

Overall Contributors

PersonTokensPropCommitsCommitProp
Jens Axboe99174.01%16.25%
Bartlomiej Zolnierkiewicz23417.48%1168.75%
Sergei Shtylyov1027.62%212.50%
Clemens Buchacher110.82%16.25%
Arnd Bergmann10.07%16.25%
Total1339100.00%16100.00%
Directory: drivers/ide
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