--- /dev/null
+/*
+ * 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;
+}
Code Review / kvmfornfv.git / blobdiff