diff options
| author | Tejun Heo <htejun@gmail.com> | 2007-11-19 16:03:44 +0900 |
|---|---|---|
| committer | Jeff Garzik <jeff@garzik.org> | 2008-01-23 05:24:10 -0500 |
| commit | 49f290903935612aadab3899a4aca884c1140348 (patch) | |
| tree | 93e98e81a7d359c679ce081295d939be948c1c80 /drivers/ata/ahci.c | |
| parent | 51dbd490614e6228e9b2b198bd4f5f76ef961059 (diff) | |
ahci: update PCS programming
For intel ones, ahci unconditionally OR'd 0xf to PCS. This isn't
correct for the following cases.
* ich6/7m's which only implement P0 and P2 (0xf works fine tho)
* ich8/9's which have six ports and needs 0x3f to enable all ports
This patch updates PCS programming such that...
* port_map determined by ahci_save_initial_config() is OR'd instead of 0xf
* PCS is updated only if necessary (there are turned off enable bits)
port_map is determined from PORTS_IMPL PCI register which is
implemented as write or write-once register. If the register isn't
programmed, ahci automatically generates it from number of ports,
which is good enough for PCS programming. ICH6/7M are probably the
only ones where non-contiguous enable bits are necessary && PORTS_IMPL
isn't programmed properly but they're proven to work reliably with 0xf
anyway.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Diffstat (limited to 'drivers/ata/ahci.c')
| -rw-r--r-- | drivers/ata/ahci.c | 7 |
1 files changed, 5 insertions, 2 deletions
diff --git a/drivers/ata/ahci.c b/drivers/ata/ahci.c index 54f38c21dd9..ef5e6b6e6e6 100644 --- a/drivers/ata/ahci.c +++ b/drivers/ata/ahci.c @@ -1036,6 +1036,7 @@ static int ahci_deinit_port(struct ata_port *ap, const char **emsg) static int ahci_reset_controller(struct ata_host *host) { struct pci_dev *pdev = to_pci_dev(host->dev); + struct ahci_host_priv *hpriv = host->private_data; void __iomem *mmio = host->iomap[AHCI_PCI_BAR]; u32 tmp; @@ -1078,8 +1079,10 @@ static int ahci_reset_controller(struct ata_host *host) /* configure PCS */ pci_read_config_word(pdev, 0x92, &tmp16); - tmp16 |= 0xf; - pci_write_config_word(pdev, 0x92, tmp16); + if ((tmp16 & hpriv->port_map) != hpriv->port_map) { + tmp16 |= hpriv->port_map; + pci_write_config_word(pdev, 0x92, tmp16); + } } return 0; |