Hello.
Tejun Heo wrote:
Okay, here's another try at fixing the detection bug. I went through
intel ich docs and compared with the ide piix driver. This patch
fixes the following problems.
diff --git a/drivers/ata/ata_piix.c b/drivers/ata/ata_piix.c
index c6bf1a3..51f55a0 100644
--- a/drivers/ata/ata_piix.c
+++ b/drivers/ata/ata_piix.c
@@ -728,8 +728,14 @@ static void piix_set_piomode (struct ata_port *ap, struct ata_device *adev)
if (adev->class == ATA_DEV_ATA)
control |= 4; /* PPE enable */
+ /* PIO configuration clears DTE unconditionally. It will be
+ * programmed in set_dmamode which is guaranteed to be called
+ * after set_piomode if any DMA mode is available.
+ */
Actually, I think ata_timing_merge() should just be performed when setting
MWDMA mode... This should be the right thing to do in most cases (however,
this hardware has some complications in the form of only 2-bit wide
active/recovery counts and 2 fast timing bank select bits)...
pci_read_config_word(dev, master_port, &master_data);
if (is_slave) {
+ /* clear TIME1|IE1|PPE1|DTE1 */
+ master_data &= 0xff0f;
Yeah, I've fixed this oversight in piix.c...
/* Enable SITRE (seperate slave timing register) */
master_data |= 0x4000;
/* enable PPE1, IE1 and TIME1 as needed */
@@ -737,12 +743,14 @@ static void piix_set_piomode (struct ata_port *ap, struct ata_device *adev)
pci_read_config_byte(dev, slave_port, &slave_data);
slave_data &= (ap->port_no ? 0x0f : 0xf0);
/* Load the timing nibble for this slave */
- slave_data |= ((timings[pio][0] << 2) | timings[pio][1]) << (ap->port_no ? 4 : 0);
+ slave_data |= ((timings[pio][0] << 2) | timings[pio][1])
+ << (ap->port_no ? 4 : 0);
} else {
- /* Master keeps the bits in a different format */
- master_data &= 0xccf8;
+ /* clear ISP|RCT|TIME0|IE0|PPE0|DTE0 */
+ master_data &= 0xccf0;
/* Enable PPE, IE and TIME as appropriate */
master_data |= control;
+ /* load ISP and RCT */
master_data |=
(timings[pio][0] << 12) |
(timings[pio][1] << 8);
@@ -859,7 +867,7 @@ static void do_pata_set_dmamode (struct ata_port *ap, struct ata_device *adev, i
master_data &= 0xFF4F; /* Mask out IORDY|TIME1|DMAONLY */
master_data |= control << 4;
pci_read_config_byte(dev, 0x44, &slave_data);
- slave_data &= (0x0F + 0xE1 * ap->port_no);
+ slave_data &= (ap->port_no ? 0x0f : 0xf0);
/* Load the matching timing */
slave_data |= ((timings[pio][0] << 2) | timings[pio][1]) << (ap->port_no ? 4 : 0);
pci_write_config_byte(dev, 0x44, slave_data);
@@ -871,8 +879,11 @@ static void do_pata_set_dmamode (struct ata_port *ap, struct ata_device *adev, i
(timings[pio][0] << 12) |
(timings[pio][1] << 8);
}
- udma_enable &= ~(1 << devid);
- pci_write_config_word(dev, master_port, master_data);
+
+ if (ap->udma_mask) {
+ udma_enable &= ~(1 << devid);
+ pci_write_config_word(dev, master_port, master_data);
+ }
I've also noticed that this is done at the end of piix_set_piomode() and I
see no reason why. Isn't it just a leftover from the piix.c brokenness? This
driver coupled PIO and UDMA timing updates for no conceivable reason?
MBR, Sergei
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