From 5fd216bbb277b645109a889c489e13a7aafbc304 Mon Sep 17 00:00:00 2001 From: Bartlomiej Zolnierkiewicz Date: Wed, 16 May 2007 00:51:43 +0200 Subject: cs5530/sc1200: add ->udma_filter methods CS5530/SC1200 specifies that two drives on the same cable cannot mix UDMA/MDMA. Add {cs5530,sc1200}_udma_filter() to handle this. This also makes it possible to remove open-coded best DMA mode selection and use standard ide_use_dma()/ide_max_dma_mode() helpers. While at it bump version numbers. There should be no functionality changes caused by this patch. Signed-off-by: Bartlomiej Zolnierkiewicz --- drivers/ide/pci/cs5530.c | 120 +++++++++++++++++++++-------------------------- 1 file changed, 54 insertions(+), 66 deletions(-) (limited to 'drivers/ide/pci/cs5530.c') diff --git a/drivers/ide/pci/cs5530.c b/drivers/ide/pci/cs5530.c index b2d7c132ef4..845500115f3 100644 --- a/drivers/ide/pci/cs5530.c +++ b/drivers/ide/pci/cs5530.c @@ -1,10 +1,10 @@ /* - * linux/drivers/ide/pci/cs5530.c Version 0.7 Sept 10, 2002 + * linux/drivers/ide/pci/cs5530.c Version 0.71 Mar 10 2007 * * Copyright (C) 2000 Andre Hedrick - * Ditto of GNU General Public License. - * * Copyright (C) 2000 Mark Lord + * Copyright (C) 2007 Bartlomiej Zolnierkiewicz + * * May be copied or modified under the terms of the GNU General Public License * * Development of this chipset driver was funded @@ -88,79 +88,66 @@ static void cs5530_tuneproc (ide_drive_t *drive, u8 pio) /* pio=255 means "autot } /** - * cs5530_config_dma - select/set DMA and UDMA modes + * cs5530_udma_filter - UDMA filter + * @drive: drive + * + * cs5530_udma_filter() does UDMA mask filtering for the given drive + * taking into the consideration capabilities of the mate device. + * + * The CS5530 specifies that two drives sharing a cable cannot mix + * UDMA/MDMA. It has to be one or the other, for the pair, though + * different timings can still be chosen for each drive. We could + * set the appropriate timing bits on the fly, but that might be + * a bit confusing. So, for now we statically handle this requirement + * by looking at our mate drive to see what it is capable of, before + * choosing a mode for our own drive. + * + * Note: This relies on the fact we never fail from UDMA to MWDMA2 + * but instead drop to PIO. + */ + +static u8 cs5530_udma_filter(ide_drive_t *drive) +{ + ide_hwif_t *hwif = drive->hwif; + ide_drive_t *mate = &hwif->drives[(drive->dn & 1) ^ 1]; + struct hd_driveid *mateid = mate->id; + u8 mask = hwif->ultra_mask; + + if (mate->present == 0) + goto out; + + if ((mateid->capability & 1) && __ide_dma_bad_drive(mate) == 0) { + if ((mateid->field_valid & 4) && (mateid->dma_ultra & 7)) + goto out; + if ((mateid->field_valid & 2) && (mateid->dma_mword & 7)) + mask = 0; + } +out: + return mask; +} + +/** + * cs5530_config_dma - set DMA/UDMA mode * @drive: drive to tune * - * cs5530_config_dma() handles selection/setting of DMA/UDMA modes - * for both the chipset and drive. The CS5530 has limitations about - * mixing DMA/UDMA on the same cable. + * cs5530_config_dma() handles setting of DMA/UDMA mode + * for both the chipset and drive. */ - -static int cs5530_config_dma (ide_drive_t *drive) + +static int cs5530_config_dma(ide_drive_t *drive) { - int udma_ok = 1, mode = 0; - ide_hwif_t *hwif = HWIF(drive); - int unit = drive->select.b.unit; - ide_drive_t *mate = &hwif->drives[unit^1]; - struct hd_driveid *id = drive->id; - unsigned int reg, timings = 0; - unsigned long basereg; + ide_hwif_t *hwif = drive->hwif; + unsigned int reg, timings = 0; + unsigned long basereg; + u8 unit = drive->dn & 1, mode = 0; /* * Default to DMA-off in case we run into trouble here. */ hwif->dma_off_quietly(drive); - /* - * The CS5530 specifies that two drives sharing a cable cannot - * mix UDMA/MDMA. It has to be one or the other, for the pair, - * though different timings can still be chosen for each drive. - * We could set the appropriate timing bits on the fly, - * but that might be a bit confusing. So, for now we statically - * handle this requirement by looking at our mate drive to see - * what it is capable of, before choosing a mode for our own drive. - * - * Note: This relies on the fact we never fail from UDMA to MWDMA_2 - * but instead drop to PIO - */ - if (mate->present) { - struct hd_driveid *mateid = mate->id; - if (mateid && (mateid->capability & 1) && - !__ide_dma_bad_drive(mate)) { - if ((mateid->field_valid & 4) && - (mateid->dma_ultra & 7)) - udma_ok = 1; - else if ((mateid->field_valid & 2) && - (mateid->dma_mword & 7)) - udma_ok = 0; - else - udma_ok = 1; - } - } - - /* - * Now see what the current drive is capable of, - * selecting UDMA only if the mate said it was ok. - */ - if (id && (id->capability & 1) && drive->autodma && - !__ide_dma_bad_drive(drive)) { - if (udma_ok && (id->field_valid & 4) && (id->dma_ultra & 7)) { - if (id->dma_ultra & 4) - mode = XFER_UDMA_2; - else if (id->dma_ultra & 2) - mode = XFER_UDMA_1; - else if (id->dma_ultra & 1) - mode = XFER_UDMA_0; - } - if (!mode && (id->field_valid & 2) && (id->dma_mword & 7)) { - if (id->dma_mword & 4) - mode = XFER_MW_DMA_2; - else if (id->dma_mword & 2) - mode = XFER_MW_DMA_1; - else if (id->dma_mword & 1) - mode = XFER_MW_DMA_0; - } - } + if (ide_use_dma(drive)) + mode = ide_max_dma_mode(drive); /* * Tell the drive to switch to the new mode; abort on failure. @@ -332,6 +319,7 @@ static void __devinit init_hwif_cs5530 (ide_hwif_t *hwif) hwif->ultra_mask = 0x07; hwif->mwdma_mask = 0x07; + hwif->udma_filter = cs5530_udma_filter; hwif->ide_dma_check = &cs5530_config_dma; if (!noautodma) hwif->autodma = 1; -- cgit v1.2.3