ahci: disable DEVSLP for Intel Valleyview

On Intel Valleyview SoC, SATA device sleep is not reliable. When
DEVSLP is attempted on certain SSDs, port_devslp write would fail
and result in malfunction of AHCI controller. AHCI controller may
be not shown in PCI enumeration after reset. Complete power source
removal may be required to recover from this failure. So we blacklist
this device and override host device reported capabilities such that
device LPM will only attempt slumber but not DEVSLP.

Signed-off-by: Jacob Pan <jacob.jun.pan@linux.intel.com>
Acked-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Tejun Heo <tj@kernel.org>

diff --git a/drivers/ata/ahci.c b/drivers/ata/ahci.c
index 71e15b73513d22ed2bf5ac34afec9b5f42679fe7..60707814a84b19e2581d6309c2a17d4823d1e015 100644 (file)
--- a/drivers/ata/ahci.c
+++ b/drivers/ata/ahci.c
@@ -1115,6 +1115,17 @@ static bool ahci_broken_online(struct pci_dev *pdev)
        return pdev->bus->number == (val >> 8) && pdev->devfn == (val & 0xff);
 }
 
+static bool ahci_broken_devslp(struct pci_dev *pdev)
+{
+       /* device with broken DEVSLP but still showing SDS capability */
+       static const struct pci_device_id ids[] = {
+               { PCI_VDEVICE(INTEL, 0x0f23)}, /* Valleyview SoC */
+               {}
+       };
+
+       return pci_match_id(ids, pdev);
+}
+
 #ifdef CONFIG_ATA_ACPI
 static void ahci_gtf_filter_workaround(struct ata_host *host)
 {
@@ -1364,6 +1375,10 @@ static int ahci_init_one(struct pci_dev *pdev, const struct pci_device_id *ent)
 
        hpriv->mmio = pcim_iomap_table(pdev)[ahci_pci_bar];
 
+       /* must set flag prior to save config in order to take effect */
+       if (ahci_broken_devslp(pdev))
+               hpriv->flags |= AHCI_HFLAG_NO_DEVSLP;
+
        /* save initial config */
        ahci_pci_save_initial_config(pdev, hpriv);
 

diff --git a/drivers/ata/ahci.h b/drivers/ata/ahci.h
index b5eb886da22635c3c76775bc0ef6374af3464b98..af63c75c20011e10d76be66edb27d595cb47978c 100644 (file)
--- a/drivers/ata/ahci.h
+++ b/drivers/ata/ahci.h
@@ -236,6 +236,7 @@ enum {
                                                        port start (wait until
                                                        error-handling stage) */
        AHCI_HFLAG_MULTI_MSI            = (1 << 16), /* multiple PCI MSIs */
+       AHCI_HFLAG_NO_DEVSLP            = (1 << 17), /* no device sleep */
 
        /* ap->flags bits */
 

diff --git a/drivers/ata/libahci.c b/drivers/ata/libahci.c
index 6bd4f660b4e15966ca2c351b4501c0521491de32..b9861453fc8148612a740418f5fee3088d7b65a1 100644 (file)
--- a/drivers/ata/libahci.c
+++ b/drivers/ata/libahci.c
@@ -452,6 +452,13 @@ void ahci_save_initial_config(struct device *dev,
                cap &= ~HOST_CAP_SNTF;
        }
 
+       if ((cap2 & HOST_CAP2_SDS) && (hpriv->flags & AHCI_HFLAG_NO_DEVSLP)) {
+               dev_info(dev,
+                        "controller can't do DEVSLP, turning off\n");
+               cap2 &= ~HOST_CAP2_SDS;
+               cap2 &= ~HOST_CAP2_SADM;
+       }
+
        if (!(cap & HOST_CAP_FBS) && (hpriv->flags & AHCI_HFLAG_YES_FBS)) {
                dev_info(dev, "controller can do FBS, turning on CAP_FBS\n");
                cap |= HOST_CAP_FBS;