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ide: rework the code for selecting the best DMA transfer mode (v3)

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Depends on the "ide: fix UDMA/MWDMA/SWDMA masks" patch.

* add ide_hwif_t.udma_filter hook for filtering UDMA mask
  (use it in alim15x3, hpt366, siimage and serverworks drivers)
* add ide_max_dma_mode() for finding best DMA mode for the device
  (loosely based on some older libata-core.c code)
* convert ide_dma_speed() users to use ide_max_dma_mode()
* make ide_rate_filter() take "ide_drive_t *drive" as an argument instead
  of "u8 mode" and teach it to how to use UDMA mask to do filtering
* use ide_rate_filter() in hpt366 driver
* remove no longer needed ide_dma_speed() and *_ratemask()
* unexport eighty_ninty_three()

v2:
* rename ->filter_udma_mask to ->udma_filter
  [ Suggested by Sergei Shtylyov <sshtylyov@ru.mvista.com>. ]

v3:
* updated for scc_pata driver (fixes XFER_UDMA_6 filtering for user-space
  originated transfer mode change requests when 100MHz clock is used)

Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
This commit is contained in:
Bartlomiej Zolnierkiewicz
2007-05-10 00:01:08 +02:00
parent 1813720723
commit 2d5eaa6dd7
27 changed files with 236 additions and 574 deletions
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74
drivers/ide/ide-dma.c
View File

@@ -705,6 +705,80 @@ int ide_use_dma(ide_drive_t *drive)
EXPORT_SYMBOL_GPL(ide_use_dma);
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)
{
struct hd_driveid *id = drive->id;
ide_hwif_t *hwif = drive->hwif;
unsigned int mask = 0;
switch(base) {
case XFER_UDMA_0:
if ((id->field_valid & 4) == 0)
break;
mask = id->dma_ultra & hwif->ultra_mask;
if (hwif->udma_filter)
mask &= hwif->udma_filter(drive);
if ((mask & 0x78) && (eighty_ninty_three(drive) == 0))
mask &= 0x07;
break;
case XFER_MW_DMA_0:
mask = id->dma_mword & hwif->mwdma_mask;
break;
case XFER_SW_DMA_0:
mask = id->dma_1word & hwif->swdma_mask;
break;
default:
BUG();
break;
}
return mask;
}
/**
* ide_max_dma_mode - compute DMA speed
* @drive: IDE device
*
* Checks the drive capabilities and returns the speed to use
* for the DMA transfer. Returns 0 if the drive is incapable
* of DMA transfers.
*/
u8 ide_max_dma_mode(ide_drive_t *drive)
{
ide_hwif_t *hwif = drive->hwif;
unsigned int mask;
int x, i;
u8 mode = 0;
if (drive->media != ide_disk && hwif->atapi_dma == 0)
return 0;
for (i = 0; i < ARRAY_SIZE(xfer_mode_bases); i++) {
mask = ide_get_mode_mask(drive, xfer_mode_bases[i]);
x = fls(mask) - 1;
if (x >= 0) {
mode = xfer_mode_bases[i] + x;
break;
}
}
printk(KERN_DEBUG "%s: selected mode 0x%x\n", drive->name, mode);
return mode;
}
EXPORT_SYMBOL_GPL(ide_max_dma_mode);
void ide_dma_verbose(ide_drive_t *drive)
{
struct hd_driveid *id = drive->id;