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authorAlan Cox <alan@lxorguk.ukuu.org.uk>2007-06-07 19:19:15 +0400
committerJeff Garzik <jeff@garzik.org>2007-06-10 06:40:28 +0400
commitd92e74d353345d19f762e9501a50b0a5f43f7ba8 (patch)
tree9a526823ddba8dd8cd07bb5d918acf7c5e820db7 /drivers/ata/libata-sff.c
parent0522b2869d89b095bf417c8cc6fa404842e91903 (diff)
downloadlinux-d92e74d353345d19f762e9501a50b0a5f43f7ba8.tar.xz
libata-core/sff: Fix multiple assumptions about DMA
The ata IRQ ack functions are only used when debugging. Unfortunately almost every controller that calls them can cause crashes in some configurations as there are missing checks for bmdma presence. In addition ata_port_start insists of installing DMA buffers and pad buffers for controllers regardless. The SFF controllers actually need to make that decision dynamically at controller setup time and all need the same helper - so we add ata_sff_port_start. Future patches will switch the SFF drivers to use this. Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Jeff Garzik <jeff@garzik.org>
Diffstat (limited to 'drivers/ata/libata-sff.c')
-rw-r--r--drivers/ata/libata-sff.c37
1 files changed, 29 insertions, 8 deletions
diff --git a/drivers/ata/libata-sff.c b/drivers/ata/libata-sff.c
index e35d13466c69..ce84805ba5f1 100644
--- a/drivers/ata/libata-sff.c
+++ b/drivers/ata/libata-sff.c
@@ -80,25 +80,25 @@ u8 ata_dummy_irq_on (struct ata_port *ap) { return 0; }
u8 ata_irq_ack(struct ata_port *ap, unsigned int chk_drq)
{
unsigned int bits = chk_drq ? ATA_BUSY | ATA_DRQ : ATA_BUSY;
- u8 host_stat, post_stat, status;
+ u8 host_stat = 0, post_stat = 0, status;
status = ata_busy_wait(ap, bits, 1000);
if (status & bits)
if (ata_msg_err(ap))
printk(KERN_ERR "abnormal status 0x%X\n", status);
- /* get controller status; clear intr, err bits */
- host_stat = ioread8(ap->ioaddr.bmdma_addr + ATA_DMA_STATUS);
- iowrite8(host_stat | ATA_DMA_INTR | ATA_DMA_ERR,
- ap->ioaddr.bmdma_addr + ATA_DMA_STATUS);
-
- post_stat = ioread8(ap->ioaddr.bmdma_addr + ATA_DMA_STATUS);
+ if (ap->ioaddr.bmdma_addr) {
+ /* get controller status; clear intr, err bits */
+ host_stat = ioread8(ap->ioaddr.bmdma_addr + ATA_DMA_STATUS);
+ iowrite8(host_stat | ATA_DMA_INTR | ATA_DMA_ERR,
+ ap->ioaddr.bmdma_addr + ATA_DMA_STATUS);
+ post_stat = ioread8(ap->ioaddr.bmdma_addr + ATA_DMA_STATUS);
+ }
if (ata_msg_intr(ap))
printk(KERN_INFO "%s: irq ack: host_stat 0x%X, new host_stat 0x%X, drv_stat 0x%X\n",
__FUNCTION__,
host_stat, post_stat, status);
-
return status;
}
@@ -516,6 +516,27 @@ void ata_bmdma_post_internal_cmd(struct ata_queued_cmd *qc)
ata_bmdma_stop(qc);
}
+/**
+ * ata_sff_port_start - Set port up for dma.
+ * @ap: Port to initialize
+ *
+ * Called just after data structures for each port are
+ * initialized. Allocates space for PRD table if the device
+ * is DMA capable SFF.
+ *
+ * May be used as the port_start() entry in ata_port_operations.
+ *
+ * LOCKING:
+ * Inherited from caller.
+ */
+
+int ata_sff_port_start(struct ata_port *ap)
+{
+ if (ap->ioaddr.bmdma_addr)
+ return ata_port_start(ap);
+ return 0;
+}
+
#ifdef CONFIG_PCI
static int ata_resources_present(struct pci_dev *pdev, int port)