On Fri, Sep 21 2007, Peer Chen wrote: > According to the description of section 5.2.2.1 and 10.1.2 of AHCI specification rev1_1/rev1_2, GHC.HR shall only be set to ¡®1¡¯ > by software when GHC.AE is set to ¡®1¡¯. > > Signed-off-by: Peer Chen <peerchen@xxxxxxxxx> > --- > --- linux-2.6.23-rc7/drivers/ata/ahci.c.orig 2007-09-20 11:01:55.000000000 -0400 > +++ linux-2.6.23-rc7/drivers/ata/ahci.c 2007-09-20 11:07:31.000000000 -0400 > @@ -834,6 +834,10 @@ static int ahci_reset_controller(struct > void __iomem *mmio = host->iomap[AHCI_PCI_BAR]; > u32 tmp; > > + /* turn on AHCI mode before controller reset*/ > + writel(HOST_AHCI_EN, mmio + HOST_CTL); > + (void) readl(mmio + HOST_CTL); /* flush */ > + > /* global controller reset */ > tmp = readl(mmio + HOST_CTL); > if ((tmp & HOST_RESET) == 0) { I appreciate the readl() flushes, but in this particular case we end up reading the exact offset again below. -- Jens Axboe - To unsubscribe from this list: send the line "unsubscribe linux-ide" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html