Messages in this thread | | | Date | Mon, 25 Apr 2011 14:26:17 +0400 | From | Sergei Shtylyov <> | Subject | Re: [PATCH 1/1] libata: ahci_start_engine compliant to AHCI spec |
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Hello.
On 23-04-2011 10:58, Jian Peng wrote:
> At the end of section 10.1 of AHCI spec (rev 1.3), it states
> Software shall not set PxCMD.ST to 1 until it is determined that > a functoinal device is present on the port as determined by > PxTFD.STS.BSY=0, PxTFD.STS.DRQ=0 and PxSSTS.DET=3h
> Even though most AHCI host controller works without this check,
"Most" requires plural noun, no?
> specific controller will fail under this condition.
> Signed-off-by: Jian Peng<jipeng2005@gmail.com> [...]
> diff --git a/drivers/ata/libahci.c b/drivers/ata/libahci.c > index 26d4523..83ed544 100644 > --- a/drivers/ata/libahci.c > +++ b/drivers/ata/libahci.c > @@ -539,6 +539,27 @@ void ahci_start_engine(struct ata_port *ap) > { > void __iomem *port_mmio = ahci_port_base(ap); > u32 tmp; > + u8 status; > + > + status = readl(port_mmio + PORT_TFDATA) & 0xFF;
Masking is not necessary.
> + > + /* > + * At end of section 10.1 of AHCI spec (rev 1.3), it states > + * Software shall not set PxCMD.ST to 1 until it is determined > + * that a functoinal device is present on the port as determined by > + * PxTFD.STS.BSY=0, PxTFD.STS.DRQ=0 and PxSSTS.DET=3h > + * > + * Even though most AHCI host controllers work without this check,
Same about grammar here.
> + * specific controller will fail under this condition > + */ > + if (status& (ATA_BUSY | ATA_DRQ)) > + return; > + else {
{} should be used on both branches, according to CodingStyle.
WBR, Sergei
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