diff options
Diffstat (limited to 'drivers/ide/ide-dma.c')
-rw-r--r-- | drivers/ide/ide-dma.c | 553 |
1 files changed, 553 insertions, 0 deletions
diff --git a/drivers/ide/ide-dma.c b/drivers/ide/ide-dma.c new file mode 100644 index 000000000..17a65ac56 --- /dev/null +++ b/drivers/ide/ide-dma.c @@ -0,0 +1,553 @@ +/* + * IDE DMA support (including IDE PCI BM-DMA). + * + * Copyright (C) 1995-1998 Mark Lord + * Copyright (C) 1999-2000 Andre Hedrick <andre@linux-ide.org> + * Copyright (C) 2004, 2007 Bartlomiej Zolnierkiewicz + * + * May be copied or modified under the terms of the GNU General Public License + * + * DMA is supported for all IDE devices (disk drives, cdroms, tapes, floppies). + */ + +/* + * Special Thanks to Mark for his Six years of work. + */ + +/* + * Thanks to "Christopher J. Reimer" <reimer@doe.carleton.ca> for + * fixing the problem with the BIOS on some Acer motherboards. + * + * Thanks to "Benoit Poulot-Cazajous" <poulot@chorus.fr> for testing + * "TX" chipset compatibility and for providing patches for the "TX" chipset. + * + * Thanks to Christian Brunner <chb@muc.de> for taking a good first crack + * at generic DMA -- his patches were referred to when preparing this code. + * + * Most importantly, thanks to Robert Bringman <rob@mars.trion.com> + * for supplying a Promise UDMA board & WD UDMA drive for this work! + */ + +#include <linux/types.h> +#include <linux/gfp.h> +#include <linux/kernel.h> +#include <linux/export.h> +#include <linux/ide.h> +#include <linux/scatterlist.h> +#include <linux/dma-mapping.h> + +static const struct drive_list_entry drive_whitelist[] = { + { "Micropolis 2112A" , NULL }, + { "CONNER CTMA 4000" , NULL }, + { "CONNER CTT8000-A" , NULL }, + { "ST34342A" , NULL }, + { NULL , NULL } +}; + +static const struct drive_list_entry drive_blacklist[] = { + { "WDC AC11000H" , NULL }, + { "WDC AC22100H" , NULL }, + { "WDC AC32500H" , NULL }, + { "WDC AC33100H" , NULL }, + { "WDC AC31600H" , NULL }, + { "WDC AC32100H" , "24.09P07" }, + { "WDC AC23200L" , "21.10N21" }, + { "Compaq CRD-8241B" , NULL }, + { "CRD-8400B" , NULL }, + { "CRD-8480B", NULL }, + { "CRD-8482B", NULL }, + { "CRD-84" , NULL }, + { "SanDisk SDP3B" , NULL }, + { "SanDisk SDP3B-64" , NULL }, + { "SANYO CD-ROM CRD" , NULL }, + { "HITACHI CDR-8" , NULL }, + { "HITACHI CDR-8335" , NULL }, + { "HITACHI CDR-8435" , NULL }, + { "Toshiba CD-ROM XM-6202B" , NULL }, + { "TOSHIBA CD-ROM XM-1702BC", NULL }, + { "CD-532E-A" , NULL }, + { "E-IDE CD-ROM CR-840", NULL }, + { "CD-ROM Drive/F5A", NULL }, + { "WPI CDD-820", NULL }, + { "SAMSUNG CD-ROM SC-148C", NULL }, + { "SAMSUNG CD-ROM SC", NULL }, + { "ATAPI CD-ROM DRIVE 40X MAXIMUM", NULL }, + { "_NEC DV5800A", NULL }, + { "SAMSUNG CD-ROM SN-124", "N001" }, + { "Seagate STT20000A", NULL }, + { "CD-ROM CDR_U200", "1.09" }, + { NULL , NULL } + +}; + +/** + * ide_dma_intr - IDE DMA interrupt handler + * @drive: the drive the interrupt is for + * + * Handle an interrupt completing a read/write DMA transfer on an + * IDE device + */ + +ide_startstop_t ide_dma_intr(ide_drive_t *drive) +{ + ide_hwif_t *hwif = drive->hwif; + struct ide_cmd *cmd = &hwif->cmd; + u8 stat = 0, dma_stat = 0; + + drive->waiting_for_dma = 0; + dma_stat = hwif->dma_ops->dma_end(drive); + ide_dma_unmap_sg(drive, cmd); + stat = hwif->tp_ops->read_status(hwif); + + if (OK_STAT(stat, DRIVE_READY, drive->bad_wstat | ATA_DRQ)) { + if (!dma_stat) { + if ((cmd->tf_flags & IDE_TFLAG_FS) == 0) + ide_finish_cmd(drive, cmd, stat); + else + ide_complete_rq(drive, 0, + blk_rq_sectors(cmd->rq) << 9); + return ide_stopped; + } + printk(KERN_ERR "%s: %s: bad DMA status (0x%02x)\n", + drive->name, __func__, dma_stat); + } + return ide_error(drive, "dma_intr", stat); +} + +int ide_dma_good_drive(ide_drive_t *drive) +{ + return ide_in_drive_list(drive->id, drive_whitelist); +} + +/** + * ide_dma_map_sg - map IDE scatter gather for DMA I/O + * @drive: the drive to map the DMA table for + * @cmd: command + * + * Perform the DMA mapping magic necessary to access the source or + * target buffers of a request via DMA. The lower layers of the + * kernel provide the necessary cache management so that we can + * operate in a portable fashion. + */ + +static int ide_dma_map_sg(ide_drive_t *drive, struct ide_cmd *cmd) +{ + ide_hwif_t *hwif = drive->hwif; + struct scatterlist *sg = hwif->sg_table; + int i; + + if (cmd->tf_flags & IDE_TFLAG_WRITE) + cmd->sg_dma_direction = DMA_TO_DEVICE; + else + cmd->sg_dma_direction = DMA_FROM_DEVICE; + + i = dma_map_sg(hwif->dev, sg, cmd->sg_nents, cmd->sg_dma_direction); + if (i) { + cmd->orig_sg_nents = cmd->sg_nents; + cmd->sg_nents = i; + } + + return i; +} + +/** + * ide_dma_unmap_sg - clean up DMA mapping + * @drive: The drive to unmap + * + * Teardown mappings after DMA has completed. This must be called + * after the completion of each use of ide_build_dmatable and before + * the next use of ide_build_dmatable. Failure to do so will cause + * an oops as only one mapping can be live for each target at a given + * time. + */ + +void ide_dma_unmap_sg(ide_drive_t *drive, struct ide_cmd *cmd) +{ + ide_hwif_t *hwif = drive->hwif; + + dma_unmap_sg(hwif->dev, hwif->sg_table, cmd->orig_sg_nents, + cmd->sg_dma_direction); +} +EXPORT_SYMBOL_GPL(ide_dma_unmap_sg); + +/** + * ide_dma_off_quietly - Generic DMA kill + * @drive: drive to control + * + * Turn off the current DMA on this IDE controller. + */ + +void ide_dma_off_quietly(ide_drive_t *drive) +{ + drive->dev_flags &= ~IDE_DFLAG_USING_DMA; + ide_toggle_bounce(drive, 0); + + drive->hwif->dma_ops->dma_host_set(drive, 0); +} +EXPORT_SYMBOL(ide_dma_off_quietly); + +/** + * ide_dma_off - disable DMA on a device + * @drive: drive to disable DMA on + * + * Disable IDE DMA for a device on this IDE controller. + * Inform the user that DMA has been disabled. + */ + +void ide_dma_off(ide_drive_t *drive) +{ + printk(KERN_INFO "%s: DMA disabled\n", drive->name); + ide_dma_off_quietly(drive); +} +EXPORT_SYMBOL(ide_dma_off); + +/** + * ide_dma_on - Enable DMA on a device + * @drive: drive to enable DMA on + * + * Enable IDE DMA for a device on this IDE controller. + */ + +void ide_dma_on(ide_drive_t *drive) +{ + drive->dev_flags |= IDE_DFLAG_USING_DMA; + ide_toggle_bounce(drive, 1); + + drive->hwif->dma_ops->dma_host_set(drive, 1); +} + +int __ide_dma_bad_drive(ide_drive_t *drive) +{ + u16 *id = drive->id; + + int blacklist = ide_in_drive_list(id, drive_blacklist); + if (blacklist) { + printk(KERN_WARNING "%s: Disabling (U)DMA for %s (blacklisted)\n", + drive->name, (char *)&id[ATA_ID_PROD]); + return blacklist; + } + return 0; +} +EXPORT_SYMBOL(__ide_dma_bad_drive); + +static const u8 xfer_mode_bases[] = { + XFER_UDMA_0, + XFER_MW_DMA_0, + XFER_SW_DMA_0, +}; + +static unsigned int ide_get_mode_mask(ide_drive_t *drive, u8 base, u8 req_mode) +{ + u16 *id = drive->id; + ide_hwif_t *hwif = drive->hwif; + const struct ide_port_ops *port_ops = hwif->port_ops; + unsigned int mask = 0; + + switch (base) { + case XFER_UDMA_0: + if ((id[ATA_ID_FIELD_VALID] & 4) == 0) + break; + mask = id[ATA_ID_UDMA_MODES]; + if (port_ops && port_ops->udma_filter) + mask &= port_ops->udma_filter(drive); + else + mask &= hwif->ultra_mask; + + /* + * avoid false cable warning from eighty_ninty_three() + */ + if (req_mode > XFER_UDMA_2) { + if ((mask & 0x78) && (eighty_ninty_three(drive) == 0)) + mask &= 0x07; + } + break; + case XFER_MW_DMA_0: + mask = id[ATA_ID_MWDMA_MODES]; + + /* Also look for the CF specific MWDMA modes... */ + if (ata_id_is_cfa(id) && (id[ATA_ID_CFA_MODES] & 0x38)) { + u8 mode = ((id[ATA_ID_CFA_MODES] & 0x38) >> 3) - 1; + + mask |= ((2 << mode) - 1) << 3; + } + + if (port_ops && port_ops->mdma_filter) + mask &= port_ops->mdma_filter(drive); + else + mask &= hwif->mwdma_mask; + break; + case XFER_SW_DMA_0: + mask = id[ATA_ID_SWDMA_MODES]; + if (!(mask & ATA_SWDMA2) && (id[ATA_ID_OLD_DMA_MODES] >> 8)) { + u8 mode = id[ATA_ID_OLD_DMA_MODES] >> 8; + + /* + * if the mode is valid convert it to the mask + * (the maximum allowed mode is XFER_SW_DMA_2) + */ + if (mode <= 2) + mask = (2 << mode) - 1; + } + mask &= hwif->swdma_mask; + break; + default: + BUG(); + break; + } + + return mask; +} + +/** + * ide_find_dma_mode - compute DMA speed + * @drive: IDE device + * @req_mode: requested mode + * + * Checks the drive/host capabilities and finds the speed to use for + * the DMA transfer. The speed is then limited by the requested mode. + * + * Returns 0 if the drive/host combination is incapable of DMA transfers + * or if the requested mode is not a DMA mode. + */ + +u8 ide_find_dma_mode(ide_drive_t *drive, u8 req_mode) +{ + ide_hwif_t *hwif = drive->hwif; + unsigned int mask; + int x, i; + u8 mode = 0; + + if (drive->media != ide_disk) { + if (hwif->host_flags & IDE_HFLAG_NO_ATAPI_DMA) + return 0; + } + + for (i = 0; i < ARRAY_SIZE(xfer_mode_bases); i++) { + if (req_mode < xfer_mode_bases[i]) + continue; + mask = ide_get_mode_mask(drive, xfer_mode_bases[i], req_mode); + x = fls(mask) - 1; + if (x >= 0) { + mode = xfer_mode_bases[i] + x; + break; + } + } + + if (hwif->chipset == ide_acorn && mode == 0) { + /* + * is this correct? + */ + if (ide_dma_good_drive(drive) && + drive->id[ATA_ID_EIDE_DMA_TIME] < 150) + mode = XFER_MW_DMA_1; + } + + mode = min(mode, req_mode); + + printk(KERN_INFO "%s: %s mode selected\n", drive->name, + mode ? ide_xfer_verbose(mode) : "no DMA"); + + return mode; +} + +static int ide_tune_dma(ide_drive_t *drive) +{ + ide_hwif_t *hwif = drive->hwif; + u8 speed; + + if (ata_id_has_dma(drive->id) == 0 || + (drive->dev_flags & IDE_DFLAG_NODMA)) + return 0; + + /* consult the list of known "bad" drives */ + if (__ide_dma_bad_drive(drive)) + return 0; + + if (hwif->host_flags & IDE_HFLAG_TRUST_BIOS_FOR_DMA) + return config_drive_for_dma(drive); + + speed = ide_max_dma_mode(drive); + + if (!speed) + return 0; + + if (ide_set_dma_mode(drive, speed)) + return 0; + + return 1; +} + +static int ide_dma_check(ide_drive_t *drive) +{ + ide_hwif_t *hwif = drive->hwif; + + if (ide_tune_dma(drive)) + return 0; + + /* TODO: always do PIO fallback */ + if (hwif->host_flags & IDE_HFLAG_TRUST_BIOS_FOR_DMA) + return -1; + + ide_set_max_pio(drive); + + return -1; +} + +int ide_set_dma(ide_drive_t *drive) +{ + int rc; + + /* + * Force DMAing for the beginning of the check. + * Some chipsets appear to do interesting + * things, if not checked and cleared. + * PARANOIA!!! + */ + ide_dma_off_quietly(drive); + + rc = ide_dma_check(drive); + if (rc) + return rc; + + ide_dma_on(drive); + + return 0; +} + +void ide_check_dma_crc(ide_drive_t *drive) +{ + u8 mode; + + ide_dma_off_quietly(drive); + drive->crc_count = 0; + mode = drive->current_speed; + /* + * Don't try non Ultra-DMA modes without iCRC's. Force the + * device to PIO and make the user enable SWDMA/MWDMA modes. + */ + if (mode > XFER_UDMA_0 && mode <= XFER_UDMA_7) + mode--; + else + mode = XFER_PIO_4; + ide_set_xfer_rate(drive, mode); + if (drive->current_speed >= XFER_SW_DMA_0) + ide_dma_on(drive); +} + +void ide_dma_lost_irq(ide_drive_t *drive) +{ + printk(KERN_ERR "%s: DMA interrupt recovery\n", drive->name); +} +EXPORT_SYMBOL_GPL(ide_dma_lost_irq); + +/* + * un-busy the port etc, and clear any pending DMA status. we want to + * retry the current request in pio mode instead of risking tossing it + * all away + */ +ide_startstop_t ide_dma_timeout_retry(ide_drive_t *drive, int error) +{ + ide_hwif_t *hwif = drive->hwif; + const struct ide_dma_ops *dma_ops = hwif->dma_ops; + struct ide_cmd *cmd = &hwif->cmd; + ide_startstop_t ret = ide_stopped; + + /* + * end current dma transaction + */ + + if (error < 0) { + printk(KERN_WARNING "%s: DMA timeout error\n", drive->name); + drive->waiting_for_dma = 0; + (void)dma_ops->dma_end(drive); + ide_dma_unmap_sg(drive, cmd); + ret = ide_error(drive, "dma timeout error", + hwif->tp_ops->read_status(hwif)); + } else { + printk(KERN_WARNING "%s: DMA timeout retry\n", drive->name); + if (dma_ops->dma_clear) + dma_ops->dma_clear(drive); + printk(KERN_ERR "%s: timeout waiting for DMA\n", drive->name); + if (dma_ops->dma_test_irq(drive) == 0) { + ide_dump_status(drive, "DMA timeout", + hwif->tp_ops->read_status(hwif)); + drive->waiting_for_dma = 0; + (void)dma_ops->dma_end(drive); + ide_dma_unmap_sg(drive, cmd); + } + } + + /* + * disable dma for now, but remember that we did so because of + * a timeout -- we'll reenable after we finish this next request + * (or rather the first chunk of it) in pio. + */ + drive->dev_flags |= IDE_DFLAG_DMA_PIO_RETRY; + drive->retry_pio++; + ide_dma_off_quietly(drive); + + /* + * make sure request is sane + */ + if (hwif->rq) + hwif->rq->errors = 0; + return ret; +} + +void ide_release_dma_engine(ide_hwif_t *hwif) +{ + if (hwif->dmatable_cpu) { + int prd_size = hwif->prd_max_nents * hwif->prd_ent_size; + + dma_free_coherent(hwif->dev, prd_size, + hwif->dmatable_cpu, hwif->dmatable_dma); + hwif->dmatable_cpu = NULL; + } +} +EXPORT_SYMBOL_GPL(ide_release_dma_engine); + +int ide_allocate_dma_engine(ide_hwif_t *hwif) +{ + int prd_size; + + if (hwif->prd_max_nents == 0) + hwif->prd_max_nents = PRD_ENTRIES; + if (hwif->prd_ent_size == 0) + hwif->prd_ent_size = PRD_BYTES; + + prd_size = hwif->prd_max_nents * hwif->prd_ent_size; + + hwif->dmatable_cpu = dma_alloc_coherent(hwif->dev, prd_size, + &hwif->dmatable_dma, + GFP_ATOMIC); + if (hwif->dmatable_cpu == NULL) { + printk(KERN_ERR "%s: unable to allocate PRD table\n", + hwif->name); + return -ENOMEM; + } + + return 0; +} +EXPORT_SYMBOL_GPL(ide_allocate_dma_engine); + +int ide_dma_prepare(ide_drive_t *drive, struct ide_cmd *cmd) +{ + const struct ide_dma_ops *dma_ops = drive->hwif->dma_ops; + + if ((drive->dev_flags & IDE_DFLAG_USING_DMA) == 0 || + (dma_ops->dma_check && dma_ops->dma_check(drive, cmd))) + goto out; + ide_map_sg(drive, cmd); + if (ide_dma_map_sg(drive, cmd) == 0) + goto out_map; + if (dma_ops->dma_setup(drive, cmd)) + goto out_dma_unmap; + drive->waiting_for_dma = 1; + return 0; +out_dma_unmap: + ide_dma_unmap_sg(drive, cmd); +out_map: + ide_map_sg(drive, cmd); +out: + return 1; +} |