[libata] pata_amd: program FIFO
With 32bit PIO we can use the posted write buffers, but only for 32bit I/O
cycles. This means we must disable the FIFO for ATAPI where a final 16bit
cycle may occur.
Rework the FIFO logic so that we disable the FIFO then selectively
re-enable it when we set the timings on AMD devices. Also fix a case
where we scribbled on PCI config 0x41 of Nvidia chips when we shouldn't.
Signed-off-by: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
diff --git a/drivers/ata/pata_amd.c b/drivers/ata/pata_amd.c
index 63719ab9e..115b1cd 100644
--- a/drivers/ata/pata_amd.c
+++ b/drivers/ata/pata_amd.c
@@ -24,7 +24,7 @@
#include <linux/libata.h>
#define DRV_NAME "pata_amd"
-#define DRV_VERSION "0.3.11"
+#define DRV_VERSION "0.4.1"
/**
* timing_setup - shared timing computation and load
@@ -145,6 +145,13 @@
return ata_sff_prereset(link, deadline);
}
+/**
+ * amd_cable_detect - report cable type
+ * @ap: port
+ *
+ * AMD controller/BIOS setups record the cable type in word 0x42
+ */
+
static int amd_cable_detect(struct ata_port *ap)
{
static const u32 bitmask[2] = {0x03, 0x0C};
@@ -158,6 +165,40 @@
}
/**
+ * amd_fifo_setup - set the PIO FIFO for ATA/ATAPI
+ * @ap: ATA interface
+ * @adev: ATA device
+ *
+ * Set the PCI fifo for this device according to the devices present
+ * on the bus at this point in time. We need to turn the post write buffer
+ * off for ATAPI devices as we may need to issue a word sized write to the
+ * device as the final I/O
+ */
+
+static void amd_fifo_setup(struct ata_port *ap)
+{
+ struct ata_device *adev;
+ struct pci_dev *pdev = to_pci_dev(ap->host->dev);
+ static const u8 fifobit[2] = { 0xC0, 0x30};
+ u8 fifo = fifobit[ap->port_no];
+ u8 r;
+
+
+ ata_for_each_dev(adev, &ap->link, ENABLED) {
+ if (adev->class == ATA_DEV_ATAPI)
+ fifo = 0;
+ }
+ if (pdev->device == PCI_DEVICE_ID_AMD_VIPER_7411) /* FIFO is broken */
+ fifo = 0;
+
+ /* On the later chips the read prefetch bits become no-op bits */
+ pci_read_config_byte(pdev, 0x41, &r);
+ r &= ~fifobit[ap->port_no];
+ r |= fifo;
+ pci_write_config_byte(pdev, 0x41, r);
+}
+
+/**
* amd33_set_piomode - set initial PIO mode data
* @ap: ATA interface
* @adev: ATA device
@@ -167,21 +208,25 @@
static void amd33_set_piomode(struct ata_port *ap, struct ata_device *adev)
{
+ amd_fifo_setup(ap);
timing_setup(ap, adev, 0x40, adev->pio_mode, 1);
}
static void amd66_set_piomode(struct ata_port *ap, struct ata_device *adev)
{
+ amd_fifo_setup(ap);
timing_setup(ap, adev, 0x40, adev->pio_mode, 2);
}
static void amd100_set_piomode(struct ata_port *ap, struct ata_device *adev)
{
+ amd_fifo_setup(ap);
timing_setup(ap, adev, 0x40, adev->pio_mode, 3);
}
static void amd133_set_piomode(struct ata_port *ap, struct ata_device *adev)
{
+ amd_fifo_setup(ap);
timing_setup(ap, adev, 0x40, adev->pio_mode, 4);
}
@@ -397,6 +442,16 @@
.set_dmamode = nv133_set_dmamode,
};
+static void amd_clear_fifo(struct pci_dev *pdev)
+{
+ u8 fifo;
+ /* Disable the FIFO, the FIFO logic will re-enable it as
+ appropriate */
+ pci_read_config_byte(pdev, 0x41, &fifo);
+ fifo &= 0x0F;
+ pci_write_config_byte(pdev, 0x41, fifo);
+}
+
static int amd_init_one(struct pci_dev *pdev, const struct pci_device_id *id)
{
static const struct ata_port_info info[10] = {
@@ -503,14 +558,8 @@
if (type < 3)
ata_pci_bmdma_clear_simplex(pdev);
-
- /* Check for AMD7411 */
- if (type == 3)
- /* FIFO is broken */
- pci_write_config_byte(pdev, 0x41, fifo & 0x0F);
- else
- pci_write_config_byte(pdev, 0x41, fifo | 0xF0);
-
+ if (pdev->vendor == PCI_VENDOR_ID_AMD)
+ amd_clear_fifo(pdev);
/* Cable detection on Nvidia chips doesn't work too well,
* cache BIOS programmed UDMA mode.
*/
@@ -536,18 +585,11 @@
return rc;
if (pdev->vendor == PCI_VENDOR_ID_AMD) {
- u8 fifo;
- pci_read_config_byte(pdev, 0x41, &fifo);
- if (pdev->device == PCI_DEVICE_ID_AMD_VIPER_7411)
- /* FIFO is broken */
- pci_write_config_byte(pdev, 0x41, fifo & 0x0F);
- else
- pci_write_config_byte(pdev, 0x41, fifo | 0xF0);
+ amd_clear_fifo(pdev);
if (pdev->device == PCI_DEVICE_ID_AMD_VIPER_7409 ||
pdev->device == PCI_DEVICE_ID_AMD_COBRA_7401)
ata_pci_bmdma_clear_simplex(pdev);
}
-
ata_host_resume(host);
return 0;
}