[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>
This commit is contained in:
Alan Cox 2009-02-11 13:08:41 -08:00 committed by Jeff Garzik
parent 6be96ac15e
commit c48052cc36

View file

@ -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 @@ static int amd_pre_reset(struct ata_link *link, unsigned long deadline)
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};
@ -157,6 +164,40 @@ static int amd_cable_detect(struct ata_port *ap)
return ATA_CBL_PATA40;
}
/**
* 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
@ -167,21 +208,25 @@ static int amd_cable_detect(struct ata_port *ap)
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 @@ static struct ata_port_operations nv133_port_ops = {
.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 @@ static int amd_init_one(struct pci_dev *pdev, const struct pci_device_id *id)
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 @@ static int amd_reinit_one(struct pci_dev *pdev)
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;
}