From 5444a6f405618706eddbe1605ef8533b1b655764 Mon Sep 17 00:00:00 2001 From: Alan Cox Date: Mon, 27 Mar 2006 18:58:20 +0100 Subject: [PATCH] libata: Simplex and other mode filtering logic Add a field to the host_set called 'flags' (was host_set_flags changed to suit Jeff) Add a simplex_claimed field so we can remember who owns the DMA channel Add a ->mode_filter() hook to allow drivers to filter modes Add docs for mode_filter and set_mode Filter according to simplex state Filter cable in core This provides the needed framework to support all the mode rules found in the PATA world. The simplex filter deals with 'to spec' simplex DMA systems found in older chips. The cable filter avoids duplicating the same rules in each chip driver with PATA. Finally the mode filter is neccessary because drive/chip combinations have errata that forbid certain modes with some drives or types of ATA object. Drive speed setup remains per channel for now and the filters now use the framework Tejun put into place which cleans them up a lot from the older libata-pata patches. Signed-off-by: Alan Cox Signed-off-by: Jeff Garzik --- drivers/scsi/libata-core.c | 31 +++++++++++++++++++++++++++++-- 1 file changed, 29 insertions(+), 2 deletions(-) (limited to 'drivers/scsi') diff --git a/drivers/scsi/libata-core.c b/drivers/scsi/libata-core.c index 41659448a204..b1ddf40533b5 100644 --- a/drivers/scsi/libata-core.c +++ b/drivers/scsi/libata-core.c @@ -1818,7 +1818,7 @@ static void ata_host_set_dma(struct ata_port *ap) */ static void ata_set_mode(struct ata_port *ap) { - int i, rc; + int i, rc, used_dma = 0; /* step 1: calculate xfer_mask */ for (i = 0; i < ATA_MAX_DEVICES; i++) { @@ -1836,6 +1836,9 @@ static void ata_set_mode(struct ata_port *ap) dma_mask = ata_pack_xfermask(0, dev->mwdma_mask, dev->udma_mask); dev->pio_mode = ata_xfer_mask2mode(pio_mask); dev->dma_mode = ata_xfer_mask2mode(dma_mask); + + if (dev->dma_mode) + used_dma = 1; } /* step 2: always set host PIO timings */ @@ -1857,6 +1860,17 @@ static void ata_set_mode(struct ata_port *ap) goto err_out; } + /* + * Record simplex status. If we selected DMA then the other + * host channels are not permitted to do so. + */ + + if (used_dma && (ap->host_set->flags & ATA_HOST_SIMPLEX)) + ap->host_set->simplex_claimed = 1; + + /* + * Chip specific finalisation + */ if (ap->ops->post_set_mode) ap->ops->post_set_mode(ap); @@ -2646,13 +2660,14 @@ static int ata_dma_blacklisted(const struct ata_device *dev) */ static void ata_dev_xfermask(struct ata_port *ap, struct ata_device *dev) { + struct ata_host_set *hs = ap->host_set; unsigned long xfer_mask; int i; xfer_mask = ata_pack_xfermask(ap->pio_mask, ap->mwdma_mask, ap->udma_mask); - /* use port-wide xfermask for now */ + /* FIXME: Use port-wide xfermask for now */ for (i = 0; i < ATA_MAX_DEVICES; i++) { struct ata_device *d = &ap->device[i]; if (!ata_dev_present(d)) @@ -2662,12 +2677,23 @@ static void ata_dev_xfermask(struct ata_port *ap, struct ata_device *dev) xfer_mask &= ata_id_xfermask(d->id); if (ata_dma_blacklisted(d)) xfer_mask &= ~(ATA_MASK_MWDMA | ATA_MASK_UDMA); + /* Apply cable rule here. Don't apply it early because when + we handle hot plug the cable type can itself change */ + if (ap->cbl == ATA_CBL_PATA40) + xfer_mask &= ~(0xF8 << ATA_SHIFT_UDMA); } if (ata_dma_blacklisted(dev)) printk(KERN_WARNING "ata%u: dev %u is on DMA blacklist, " "disabling DMA\n", ap->id, dev->devno); + if (hs->flags & ATA_HOST_SIMPLEX) { + if (hs->simplex_claimed) + xfer_mask &= ~(ATA_MASK_MWDMA | ATA_MASK_UDMA); + } + if (ap->ops->mode_filter) + xfer_mask = ap->ops->mode_filter(ap, dev, xfer_mask); + ata_unpack_xfermask(xfer_mask, &dev->pio_mask, &dev->mwdma_mask, &dev->udma_mask); } @@ -4531,6 +4557,7 @@ int ata_device_add(const struct ata_probe_ent *ent) host_set->mmio_base = ent->mmio_base; host_set->private_data = ent->private_data; host_set->ops = ent->port_ops; + host_set->flags = ent->host_set_flags; /* register each port bound to this device */ for (i = 0; i < ent->n_ports; i++) { -- cgit v1.2.2