diff --git a/drivers/ata/ahci.h b/drivers/ata/ahci.h index a4faa438889c..a44c75d4c284 100644 --- a/drivers/ata/ahci.h +++ b/drivers/ata/ahci.h @@ -250,6 +250,7 @@ enum { AHCI_HFLAG_MULTI_MSI = 0, AHCI_HFLAG_MULTI_MSIX = 0, #endif + AHCI_HFLAG_WAKE_BEFORE_STOP = (1 << 22), /* wake before DMA stop */ /* ap->flags bits */ diff --git a/drivers/ata/ahci_brcmstb.c b/drivers/ata/ahci_brcmstb.c index b36cae2fd04b..e87bcec0fd7c 100644 --- a/drivers/ata/ahci_brcmstb.c +++ b/drivers/ata/ahci_brcmstb.c @@ -317,6 +317,7 @@ static int brcm_ahci_probe(struct platform_device *pdev) if (IS_ERR(hpriv)) return PTR_ERR(hpriv); hpriv->plat_data = priv; + hpriv->flags = AHCI_HFLAG_WAKE_BEFORE_STOP; brcm_sata_alpm_init(hpriv); diff --git a/drivers/ata/libahci.c b/drivers/ata/libahci.c index d61740e78d6d..284a176076f5 100644 --- a/drivers/ata/libahci.c +++ b/drivers/ata/libahci.c @@ -593,8 +593,22 @@ EXPORT_SYMBOL_GPL(ahci_start_engine); int ahci_stop_engine(struct ata_port *ap) { void __iomem *port_mmio = ahci_port_base(ap); + struct ahci_host_priv *hpriv = ap->host->private_data; u32 tmp; + /* + * On some controllers, stopping a port's DMA engine while the port + * is in ALPM state (partial or slumber) results in failures on + * subsequent DMA engine starts. For those controllers, put the + * port back in active state before stopping its DMA engine. + */ + if ((hpriv->flags & AHCI_HFLAG_WAKE_BEFORE_STOP) && + (ap->link.lpm_policy > ATA_LPM_MAX_POWER) && + ahci_set_lpm(&ap->link, ATA_LPM_MAX_POWER, ATA_LPM_WAKE_ONLY)) { + dev_err(ap->host->dev, "Failed to wake up port before engine stop\n"); + return -EIO; + } + tmp = readl(port_mmio + PORT_CMD); /* check if the HBA is idle */ @@ -689,6 +703,9 @@ static int ahci_set_lpm(struct ata_link *link, enum ata_lpm_policy policy, void __iomem *port_mmio = ahci_port_base(ap); if (policy != ATA_LPM_MAX_POWER) { + /* wakeup flag only applies to the max power policy */ + hints &= ~ATA_LPM_WAKE_ONLY; + /* * Disable interrupts on Phy Ready. This keeps us from * getting woken up due to spurious phy ready @@ -704,7 +721,8 @@ static int ahci_set_lpm(struct ata_link *link, enum ata_lpm_policy policy, u32 cmd = readl(port_mmio + PORT_CMD); if (policy == ATA_LPM_MAX_POWER || !(hints & ATA_LPM_HIPM)) { - cmd &= ~(PORT_CMD_ASP | PORT_CMD_ALPE); + if (!(hints & ATA_LPM_WAKE_ONLY)) + cmd &= ~(PORT_CMD_ASP | PORT_CMD_ALPE); cmd |= PORT_CMD_ICC_ACTIVE; writel(cmd, port_mmio + PORT_CMD); @@ -712,6 +730,9 @@ static int ahci_set_lpm(struct ata_link *link, enum ata_lpm_policy policy, /* wait 10ms to be sure we've come out of LPM state */ ata_msleep(ap, 10); + + if (hints & ATA_LPM_WAKE_ONLY) + return 0; } else { cmd |= PORT_CMD_ALPE; if (policy == ATA_LPM_MIN_POWER) diff --git a/include/linux/libata.h b/include/linux/libata.h index 851821bfd553..bec2abbd7ab2 100644 --- a/include/linux/libata.h +++ b/include/linux/libata.h @@ -526,6 +526,7 @@ enum ata_lpm_policy { enum ata_lpm_hints { ATA_LPM_EMPTY = (1 << 0), /* port empty/probing */ ATA_LPM_HIPM = (1 << 1), /* may use HIPM */ + ATA_LPM_WAKE_ONLY = (1 << 2), /* only wake up link */ }; /* forward declarations */