diff options
Diffstat (limited to 'drivers/scsi/libata-bmdma.c')
| -rw-r--r-- | drivers/scsi/libata-bmdma.c | 234 |
1 files changed, 234 insertions, 0 deletions
diff --git a/drivers/scsi/libata-bmdma.c b/drivers/scsi/libata-bmdma.c index 96b4d2160df8..a00a78b30836 100644 --- a/drivers/scsi/libata-bmdma.c +++ b/drivers/scsi/libata-bmdma.c @@ -418,6 +418,240 @@ u8 ata_altstatus(struct ata_port *ap) return inb(ap->ioaddr.altstatus_addr); } +/** + * ata_bmdma_setup_mmio - Set up PCI IDE BMDMA transaction + * @qc: Info associated with this ATA transaction. + * + * LOCKING: + * spin_lock_irqsave(host_set lock) + */ + +static void ata_bmdma_setup_mmio (struct ata_queued_cmd *qc) +{ + struct ata_port *ap = qc->ap; + unsigned int rw = (qc->tf.flags & ATA_TFLAG_WRITE); + u8 dmactl; + void __iomem *mmio = (void __iomem *) ap->ioaddr.bmdma_addr; + + /* load PRD table addr. */ + mb(); /* make sure PRD table writes are visible to controller */ + writel(ap->prd_dma, mmio + ATA_DMA_TABLE_OFS); + + /* specify data direction, triple-check start bit is clear */ + dmactl = readb(mmio + ATA_DMA_CMD); + dmactl &= ~(ATA_DMA_WR | ATA_DMA_START); + if (!rw) + dmactl |= ATA_DMA_WR; + writeb(dmactl, mmio + ATA_DMA_CMD); + + /* issue r/w command */ + ap->ops->exec_command(ap, &qc->tf); +} + +/** + * ata_bmdma_start_mmio - Start a PCI IDE BMDMA transaction + * @qc: Info associated with this ATA transaction. + * + * LOCKING: + * spin_lock_irqsave(host_set lock) + */ + +static void ata_bmdma_start_mmio (struct ata_queued_cmd *qc) +{ + struct ata_port *ap = qc->ap; + void __iomem *mmio = (void __iomem *) ap->ioaddr.bmdma_addr; + u8 dmactl; + + /* start host DMA transaction */ + dmactl = readb(mmio + ATA_DMA_CMD); + writeb(dmactl | ATA_DMA_START, mmio + ATA_DMA_CMD); + + /* Strictly, one may wish to issue a readb() here, to + * flush the mmio write. However, control also passes + * to the hardware at this point, and it will interrupt + * us when we are to resume control. So, in effect, + * we don't care when the mmio write flushes. + * Further, a read of the DMA status register _immediately_ + * following the write may not be what certain flaky hardware + * is expected, so I think it is best to not add a readb() + * without first all the MMIO ATA cards/mobos. + * Or maybe I'm just being paranoid. + */ +} + +/** + * ata_bmdma_setup_pio - Set up PCI IDE BMDMA transaction (PIO) + * @qc: Info associated with this ATA transaction. + * + * LOCKING: + * spin_lock_irqsave(host_set lock) + */ + +static void ata_bmdma_setup_pio (struct ata_queued_cmd *qc) +{ + struct ata_port *ap = qc->ap; + unsigned int rw = (qc->tf.flags & ATA_TFLAG_WRITE); + u8 dmactl; + + /* load PRD table addr. */ + outl(ap->prd_dma, ap->ioaddr.bmdma_addr + ATA_DMA_TABLE_OFS); + + /* specify data direction, triple-check start bit is clear */ + dmactl = inb(ap->ioaddr.bmdma_addr + ATA_DMA_CMD); + dmactl &= ~(ATA_DMA_WR | ATA_DMA_START); + if (!rw) + dmactl |= ATA_DMA_WR; + outb(dmactl, ap->ioaddr.bmdma_addr + ATA_DMA_CMD); + + /* issue r/w command */ + ap->ops->exec_command(ap, &qc->tf); +} + +/** + * ata_bmdma_start_pio - Start a PCI IDE BMDMA transaction (PIO) + * @qc: Info associated with this ATA transaction. + * + * LOCKING: + * spin_lock_irqsave(host_set lock) + */ + +static void ata_bmdma_start_pio (struct ata_queued_cmd *qc) +{ + struct ata_port *ap = qc->ap; + u8 dmactl; + + /* start host DMA transaction */ + dmactl = inb(ap->ioaddr.bmdma_addr + ATA_DMA_CMD); + outb(dmactl | ATA_DMA_START, + ap->ioaddr.bmdma_addr + ATA_DMA_CMD); +} + + +/** + * ata_bmdma_start - Start a PCI IDE BMDMA transaction + * @qc: Info associated with this ATA transaction. + * + * Writes the ATA_DMA_START flag to the DMA command register. + * + * May be used as the bmdma_start() entry in ata_port_operations. + * + * LOCKING: + * spin_lock_irqsave(host_set lock) + */ +void ata_bmdma_start(struct ata_queued_cmd *qc) +{ + if (qc->ap->flags & ATA_FLAG_MMIO) + ata_bmdma_start_mmio(qc); + else + ata_bmdma_start_pio(qc); +} + + +/** + * ata_bmdma_setup - Set up PCI IDE BMDMA transaction + * @qc: Info associated with this ATA transaction. + * + * Writes address of PRD table to device's PRD Table Address + * register, sets the DMA control register, and calls + * ops->exec_command() to start the transfer. + * + * May be used as the bmdma_setup() entry in ata_port_operations. + * + * LOCKING: + * spin_lock_irqsave(host_set lock) + */ +void ata_bmdma_setup(struct ata_queued_cmd *qc) +{ + if (qc->ap->flags & ATA_FLAG_MMIO) + ata_bmdma_setup_mmio(qc); + else + ata_bmdma_setup_pio(qc); +} + + +/** + * ata_bmdma_irq_clear - Clear PCI IDE BMDMA interrupt. + * @ap: Port associated with this ATA transaction. + * + * Clear interrupt and error flags in DMA status register. + * + * May be used as the irq_clear() entry in ata_port_operations. + * + * LOCKING: + * spin_lock_irqsave(host_set lock) + */ + +void ata_bmdma_irq_clear(struct ata_port *ap) +{ + if (!ap->ioaddr.bmdma_addr) + return; + + if (ap->flags & ATA_FLAG_MMIO) { + void __iomem *mmio = + ((void __iomem *) ap->ioaddr.bmdma_addr) + ATA_DMA_STATUS; + writeb(readb(mmio), mmio); + } else { + unsigned long addr = ap->ioaddr.bmdma_addr + ATA_DMA_STATUS; + outb(inb(addr), addr); + } +} + + +/** + * ata_bmdma_status - Read PCI IDE BMDMA status + * @ap: Port associated with this ATA transaction. + * + * Read and return BMDMA status register. + * + * May be used as the bmdma_status() entry in ata_port_operations. + * + * LOCKING: + * spin_lock_irqsave(host_set lock) + */ + +u8 ata_bmdma_status(struct ata_port *ap) +{ + u8 host_stat; + if (ap->flags & ATA_FLAG_MMIO) { + void __iomem *mmio = (void __iomem *) ap->ioaddr.bmdma_addr; + host_stat = readb(mmio + ATA_DMA_STATUS); + } else + host_stat = inb(ap->ioaddr.bmdma_addr + ATA_DMA_STATUS); + return host_stat; +} + + +/** + * ata_bmdma_stop - Stop PCI IDE BMDMA transfer + * @qc: Command we are ending DMA for + * + * Clears the ATA_DMA_START flag in the dma control register + * + * May be used as the bmdma_stop() entry in ata_port_operations. + * + * LOCKING: + * spin_lock_irqsave(host_set lock) + */ + +void ata_bmdma_stop(struct ata_queued_cmd *qc) +{ + struct ata_port *ap = qc->ap; + if (ap->flags & ATA_FLAG_MMIO) { + void __iomem *mmio = (void __iomem *) ap->ioaddr.bmdma_addr; + + /* clear start/stop bit */ + writeb(readb(mmio + ATA_DMA_CMD) & ~ATA_DMA_START, + mmio + ATA_DMA_CMD); + } else { + /* clear start/stop bit */ + outb(inb(ap->ioaddr.bmdma_addr + ATA_DMA_CMD) & ~ATA_DMA_START, + ap->ioaddr.bmdma_addr + ATA_DMA_CMD); + } + + /* one-PIO-cycle guaranteed wait, per spec, for HDMA1:0 transition */ + ata_altstatus(ap); /* dummy read */ +} + #ifdef CONFIG_PCI static struct ata_probe_ent * ata_probe_ent_alloc(struct device *dev, const struct ata_port_info *port) |