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WSL2-Linux-Kernel
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WSL2-Linux-Kernel/drivers/ide/ide-dma.c

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/*
* 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/module.h>
#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/timer.h>
#include <linux/mm.h>
#include <linux/interrupt.h>
#include <linux/pci.h>
#include <linux/init.h>
#include <linux/ide.h>
#include <linux/delay.h>
#include <linux/scatterlist.h>
#include <linux/dma-mapping.h>
#include <asm/io.h>
#include <asm/irq.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;
u8 stat = 0, dma_stat = 0;
dma_stat = hwif->dma_ops->dma_end(drive);
stat = hwif->tp_ops->read_status(hwif);
if (OK_STAT(stat,DRIVE_READY,drive->bad_wstat|DRQ_STAT)) {
if (!dma_stat) {
struct request *rq = HWGROUP(drive)->rq;
task_end_request(drive, rq, stat);
return ide_stopped;
}
printk(KERN_ERR "%s: dma_intr: bad DMA status (dma_stat=%x)\n",
drive->name, dma_stat);
}
return ide_error(drive, "dma_intr", stat);
}
EXPORT_SYMBOL_GPL(ide_dma_intr);
static int ide_dma_good_drive(ide_drive_t *drive)
{
return ide_in_drive_list(drive->id, drive_whitelist);
}
/**
* ide_build_sglist - map IDE scatter gather for DMA I/O
* @drive: the drive to build the DMA table for
* @rq: the request holding the sg list
*
* 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.
*/
int ide_build_sglist(ide_drive_t *drive, struct request *rq)
{
ide_hwif_t *hwif = HWIF(drive);
struct scatterlist *sg = hwif->sg_table;
ide_map_sg(drive, rq);
if (rq_data_dir(rq) == READ)
hwif->sg_dma_direction = DMA_FROM_DEVICE;
else
hwif->sg_dma_direction = DMA_TO_DEVICE;
return dma_map_sg(hwif->dev, sg, hwif->sg_nents,
hwif->sg_dma_direction);
}
EXPORT_SYMBOL_GPL(ide_build_sglist);
#ifdef CONFIG_BLK_DEV_IDEDMA_SFF
/**
* ide_build_dmatable - build IDE DMA table
*
* ide_build_dmatable() prepares a dma request. We map the command
* to get the pci bus addresses of the buffers and then build up
* the PRD table that the IDE layer wants to be fed. The code
* knows about the 64K wrap bug in the CS5530.
*
* Returns the number of built PRD entries if all went okay,
* returns 0 otherwise.
*
* May also be invoked from trm290.c
*/
int ide_build_dmatable (ide_drive_t *drive, struct request *rq)
{
ide_hwif_t *hwif = HWIF(drive);
__le32 *table = (__le32 *)hwif->dmatable_cpu;
unsigned int is_trm290 = (hwif->chipset == ide_trm290) ? 1 : 0;
unsigned int count = 0;
int i;
struct scatterlist *sg;
hwif->sg_nents = i = ide_build_sglist(drive, rq);
if (!i)
return 0;
sg = hwif->sg_table;
while (i) {
u32 cur_addr;
u32 cur_len;
cur_addr = sg_dma_address(sg);
cur_len = sg_dma_len(sg);
/*
* Fill in the dma table, without crossing any 64kB boundaries.
* Most hardware requires 16-bit alignment of all blocks,
* but the trm290 requires 32-bit alignment.
*/
while (cur_len) {
if (count++ >= PRD_ENTRIES) {
printk(KERN_ERR "%s: DMA table too small\n", drive->name);
goto use_pio_instead;
} else {
u32 xcount, bcount = 0x10000 - (cur_addr & 0xffff);
if (bcount > cur_len)
bcount = cur_len;
*table++ = cpu_to_le32(cur_addr);
xcount = bcount & 0xffff;
if (is_trm290)
xcount = ((xcount >> 2) - 1) << 16;
if (xcount == 0x0000) {
/*
* Most chipsets correctly interpret a length of 0x0000 as 64KB,
* but at least one (e.g. CS5530) misinterprets it as zero (!).
* So here we break the 64KB entry into two 32KB entries instead.
*/
if (count++ >= PRD_ENTRIES) {
printk(KERN_ERR "%s: DMA table too small\n", drive->name);
goto use_pio_instead;
}
*table++ = cpu_to_le32(0x8000);
*table++ = cpu_to_le32(cur_addr + 0x8000);
xcount = 0x8000;
}
*table++ = cpu_to_le32(xcount);
cur_addr += bcount;
cur_len -= bcount;
}
}
sg = sg_next(sg);
i--;
}
if (count) {
if (!is_trm290)
*--table |= cpu_to_le32(0x80000000);
return count;
}
printk(KERN_ERR "%s: empty DMA table?\n", drive->name);
use_pio_instead:
ide_destroy_dmatable(drive);
return 0; /* revert to PIO for this request */
}
EXPORT_SYMBOL_GPL(ide_build_dmatable);
#endif
/**
* ide_destroy_dmatable - 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_destroy_dmatable (ide_drive_t *drive)
{
ide_hwif_t *hwif = drive->hwif;
dma_unmap_sg(hwif->dev, hwif->sg_table, hwif->sg_nents,
hwif->sg_dma_direction);
}
EXPORT_SYMBOL_GPL(ide_destroy_dmatable);
#ifdef CONFIG_BLK_DEV_IDEDMA_SFF
/**
* config_drive_for_dma - attempt to activate IDE DMA
* @drive: the drive to place in DMA mode
*
* If the drive supports at least mode 2 DMA or UDMA of any kind
* then attempt to place it into DMA mode. Drives that are known to
* support DMA but predate the DMA properties or that are known
* to have DMA handling bugs are also set up appropriately based
* on the good/bad drive lists.
*/
static int config_drive_for_dma (ide_drive_t *drive)
{
ide_hwif_t *hwif = drive->hwif;
struct hd_driveid *id = drive->id;
if (drive->media != ide_disk) {
if (hwif->host_flags & IDE_HFLAG_NO_ATAPI_DMA)
return 0;
}
/*
* Enable DMA on any drive that has
* UltraDMA (mode 0/1/2/3/4/5/6) enabled
*/
if ((id->field_valid & 4) && ((id->dma_ultra >> 8) & 0x7f))
return 1;
/*
* Enable DMA on any drive that has mode2 DMA
* (multi or single) enabled
*/
if (id->field_valid & 2) /* regular DMA */
if ((id->dma_mword & 0x404) == 0x404 ||
(id->dma_1word & 0x404) == 0x404)
return 1;
/* Consult the list of known "good" drives */
if (ide_dma_good_drive(drive))
return 1;
return 0;
}
/**
* dma_timer_expiry - handle a DMA timeout
* @drive: Drive that timed out
*
* An IDE DMA transfer timed out. In the event of an error we ask
* the driver to resolve the problem, if a DMA transfer is still
* in progress we continue to wait (arguably we need to add a
* secondary 'I don't care what the drive thinks' timeout here)
* Finally if we have an interrupt we let it complete the I/O.
* But only one time - we clear expiry and if it's still not
* completed after WAIT_CMD, we error and retry in PIO.
* This can occur if an interrupt is lost or due to hang or bugs.
*/
static int dma_timer_expiry (ide_drive_t *drive)
{
ide_hwif_t *hwif = HWIF(drive);
u8 dma_stat = hwif->tp_ops->read_sff_dma_status(hwif);
printk(KERN_WARNING "%s: dma_timer_expiry: dma status == 0x%02x\n",
drive->name, dma_stat);
if ((dma_stat & 0x18) == 0x18) /* BUSY Stupid Early Timer !! */
return WAIT_CMD;
HWGROUP(drive)->expiry = NULL; /* one free ride for now */
/* 1 dmaing, 2 error, 4 intr */
if (dma_stat & 2) /* ERROR */
return -1;
if (dma_stat & 1) /* DMAing */
return WAIT_CMD;
if (dma_stat & 4) /* Got an Interrupt */
return WAIT_CMD;
return 0; /* Status is unknown -- reset the bus */
}
/**
* ide_dma_host_set - Enable/disable DMA on a host
* @drive: drive to control
*
* Enable/disable DMA on an IDE controller following generic
* bus-mastering IDE controller behaviour.
*/
void ide_dma_host_set(ide_drive_t *drive, int on)
{
ide_hwif_t *hwif = HWIF(drive);
u8 unit = (drive->select.b.unit & 0x01);
u8 dma_stat = hwif->tp_ops->read_sff_dma_status(hwif);
if (on)
dma_stat |= (1 << (5 + unit));
else
dma_stat &= ~(1 << (5 + unit));
if (hwif->host_flags & IDE_HFLAG_MMIO)
writeb(dma_stat,
(void __iomem *)(hwif->dma_base + ATA_DMA_STATUS));
else
outb(dma_stat, hwif->dma_base + ATA_DMA_STATUS);
}
EXPORT_SYMBOL_GPL(ide_dma_host_set);
#endif /* CONFIG_BLK_DEV_IDEDMA_SFF */
/**
* 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->using_dma = 0;
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->using_dma = 1;
ide_toggle_bounce(drive, 1);
drive->hwif->dma_ops->dma_host_set(drive, 1);
}
#ifdef CONFIG_BLK_DEV_IDEDMA_SFF
/**
* ide_dma_setup - begin a DMA phase
* @drive: target device
*
* Build an IDE DMA PRD (IDE speak for scatter gather table)
* and then set up the DMA transfer registers for a device
* that follows generic IDE PCI DMA behaviour. Controllers can
* override this function if they need to
*
* Returns 0 on success. If a PIO fallback is required then 1
* is returned.
*/
int ide_dma_setup(ide_drive_t *drive)
{
ide_hwif_t *hwif = drive->hwif;
struct request *rq = HWGROUP(drive)->rq;
unsigned int reading;
u8 mmio = (hwif->host_flags & IDE_HFLAG_MMIO) ? 1 : 0;
u8 dma_stat;
if (rq_data_dir(rq))
reading = 0;
else
reading = 1 << 3;
/* fall back to pio! */
if (!ide_build_dmatable(drive, rq)) {
ide_map_sg(drive, rq);
return 1;
}
/* PRD table */
if (hwif->host_flags & IDE_HFLAG_MMIO)
writel(hwif->dmatable_dma,
(void __iomem *)(hwif->dma_base + ATA_DMA_TABLE_OFS));
else
outl(hwif->dmatable_dma, hwif->dma_base + ATA_DMA_TABLE_OFS);
/* specify r/w */
if (mmio)
writeb(reading, (void __iomem *)(hwif->dma_base + ATA_DMA_CMD));
else
outb(reading, hwif->dma_base + ATA_DMA_CMD);
/* read DMA status for INTR & ERROR flags */
dma_stat = hwif->tp_ops->read_sff_dma_status(hwif);
/* clear INTR & ERROR flags */
if (mmio)
writeb(dma_stat | 6,
(void __iomem *)(hwif->dma_base + ATA_DMA_STATUS));
else
outb(dma_stat | 6, hwif->dma_base + ATA_DMA_STATUS);
drive->waiting_for_dma = 1;
return 0;
}
EXPORT_SYMBOL_GPL(ide_dma_setup);
void ide_dma_exec_cmd(ide_drive_t *drive, u8 command)
{
/* issue cmd to drive */
ide_execute_command(drive, command, &ide_dma_intr, 2*WAIT_CMD, dma_timer_expiry);
}
EXPORT_SYMBOL_GPL(ide_dma_exec_cmd);
void ide_dma_start(ide_drive_t *drive)
{
ide_hwif_t *hwif = drive->hwif;
u8 dma_cmd;
/* Note that this is done *after* the cmd has
* been issued to the drive, as per the BM-IDE spec.
* The Promise Ultra33 doesn't work correctly when
* we do this part before issuing the drive cmd.
*/
if (hwif->host_flags & IDE_HFLAG_MMIO) {
dma_cmd = readb((void __iomem *)(hwif->dma_base + ATA_DMA_CMD));
/* start DMA */
writeb(dma_cmd | 1,
(void __iomem *)(hwif->dma_base + ATA_DMA_CMD));
} else {
dma_cmd = inb(hwif->dma_base + ATA_DMA_CMD);
outb(dma_cmd | 1, hwif->dma_base + ATA_DMA_CMD);
}
hwif->dma = 1;
wmb();
}
EXPORT_SYMBOL_GPL(ide_dma_start);
/* returns 1 on error, 0 otherwise */
int __ide_dma_end (ide_drive_t *drive)
{
ide_hwif_t *hwif = drive->hwif;
u8 mmio = (hwif->host_flags & IDE_HFLAG_MMIO) ? 1 : 0;
u8 dma_stat = 0, dma_cmd = 0;
drive->waiting_for_dma = 0;
if (mmio) {
/* get DMA command mode */
dma_cmd = readb((void __iomem *)(hwif->dma_base + ATA_DMA_CMD));
/* stop DMA */
writeb(dma_cmd & ~1,
(void __iomem *)(hwif->dma_base + ATA_DMA_CMD));
} else {
dma_cmd = inb(hwif->dma_base + ATA_DMA_CMD);
outb(dma_cmd & ~1, hwif->dma_base + ATA_DMA_CMD);
}
/* get DMA status */
dma_stat = hwif->tp_ops->read_sff_dma_status(hwif);
if (mmio)
/* clear the INTR & ERROR bits */
writeb(dma_stat | 6,
(void __iomem *)(hwif->dma_base + ATA_DMA_STATUS));
else
outb(dma_stat | 6, hwif->dma_base + ATA_DMA_STATUS);
/* purge DMA mappings */
ide_destroy_dmatable(drive);
/* verify good DMA status */
hwif->dma = 0;
wmb();
return (dma_stat & 7) != 4 ? (0x10 | dma_stat) : 0;
}
EXPORT_SYMBOL(__ide_dma_end);
/* returns 1 if dma irq issued, 0 otherwise */
int ide_dma_test_irq(ide_drive_t *drive)
{
ide_hwif_t *hwif = HWIF(drive);
u8 dma_stat = hwif->tp_ops->read_sff_dma_status(hwif);
/* return 1 if INTR asserted */
if ((dma_stat & 4) == 4)
return 1;
if (!drive->waiting_for_dma)
printk(KERN_WARNING "%s: (%s) called while not waiting\n",
drive->name, __func__);
return 0;
}
EXPORT_SYMBOL_GPL(ide_dma_test_irq);
#else
static inline int config_drive_for_dma(ide_drive_t *drive) { return 0; }
#endif /* CONFIG_BLK_DEV_IDEDMA_SFF */
int __ide_dma_bad_drive (ide_drive_t *drive)
{
struct hd_driveid *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, id->model);
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)
{
struct hd_driveid *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->field_valid & 4) == 0)
break;
if (port_ops && port_ops->udma_filter)
mask = port_ops->udma_filter(drive);
else
mask = hwif->ultra_mask;
mask &= id->dma_ultra;
/*
* 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:
if ((id->field_valid & 2) == 0)
break;
if (port_ops && port_ops->mdma_filter)
mask = port_ops->mdma_filter(drive);
else
mask = hwif->mwdma_mask;
mask &= id->dma_mword;
break;
case XFER_SW_DMA_0:
if (id->field_valid & 2) {
mask = id->dma_1word & hwif->swdma_mask;
} else if (id->tDMA) {
/*
* ide_fix_driveid() doesn't convert ->tDMA to the
* CPU endianness so we need to do it here
*/
u8 mode = le16_to_cpu(id->tDMA);
/*
* 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) & 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->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;
}
EXPORT_SYMBOL_GPL(ide_find_dma_mode);
static int ide_tune_dma(ide_drive_t *drive)
{
ide_hwif_t *hwif = drive->hwif;
u8 speed;
if (drive->nodma || (drive->id->capability & 1) == 0)
return 0;
/* consult the list of known "bad" drives */
if (__ide_dma_bad_drive(drive))
return 0;
if (ide_id_dma_bug(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_id_dma_bug(ide_drive_t *drive)
{
struct hd_driveid *id = drive->id;
if (id->field_valid & 4) {
if ((id->dma_ultra >> 8) && (id->dma_mword >> 8))
goto err_out;
} else if (id->field_valid & 2) {
if ((id->dma_mword >> 8) && (id->dma_1word >> 8))
goto err_out;
}
return 0;
err_out:
printk(KERN_ERR "%s: bad DMA info in identify block\n", drive->name);
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);
}
#ifdef CONFIG_BLK_DEV_IDEDMA_SFF
void ide_dma_lost_irq (ide_drive_t *drive)
{
printk("%s: DMA interrupt recovery\n", drive->name);
}
EXPORT_SYMBOL(ide_dma_lost_irq);
void ide_dma_timeout (ide_drive_t *drive)
{
ide_hwif_t *hwif = HWIF(drive);
printk(KERN_ERR "%s: timeout waiting for DMA\n", drive->name);
if (hwif->dma_ops->dma_test_irq(drive))
return;
hwif->dma_ops->dma_end(drive);
}
EXPORT_SYMBOL(ide_dma_timeout);
void ide_release_dma_engine(ide_hwif_t *hwif)
{
if (hwif->dmatable_cpu) {
struct pci_dev *pdev = to_pci_dev(hwif->dev);
pci_free_consistent(pdev, PRD_ENTRIES * PRD_BYTES,
hwif->dmatable_cpu, hwif->dmatable_dma);
hwif->dmatable_cpu = NULL;
}
}
int ide_allocate_dma_engine(ide_hwif_t *hwif)
{
struct pci_dev *pdev = to_pci_dev(hwif->dev);
hwif->dmatable_cpu = pci_alloc_consistent(pdev,
PRD_ENTRIES * PRD_BYTES,
&hwif->dmatable_dma);
if (hwif->dmatable_cpu)
return 0;
printk(KERN_ERR "%s: -- Error, unable to allocate DMA table.\n",
hwif->name);
return 1;
}
EXPORT_SYMBOL_GPL(ide_allocate_dma_engine);
const struct ide_dma_ops sff_dma_ops = {
.dma_host_set = ide_dma_host_set,
.dma_setup = ide_dma_setup,
.dma_exec_cmd = ide_dma_exec_cmd,
.dma_start = ide_dma_start,
.dma_end = __ide_dma_end,
.dma_test_irq = ide_dma_test_irq,
.dma_timeout = ide_dma_timeout,
.dma_lost_irq = ide_dma_lost_irq,
};
EXPORT_SYMBOL_GPL(sff_dma_ops);
#endif /* CONFIG_BLK_DEV_IDEDMA_SFF */
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