[PATCH] ata: Disable AHCI ALPM feature for Ampere Computing eMAG SATA

[Suman Tripathi]

Due to hardware errata, Ampere Computing eMAG SATA can't support
AHCI ALPM feature. This patch disables the AHCI ALPM feature for
eMAG SATA.

Signed-off-by: Suman Tripathi <stripa...@amperecomputing.com>
Signed-off-by: Rameshwar Prasad Sahu <rameshwar.s...@amperecomputing.com>
---
 drivers/ata/ahci_platform.c | 13 ++++++++++++-
 1 file changed, 12 insertions(+), 1 deletion(-)

diff --git a/drivers/ata/ahci_platform.c b/drivers/ata/ahci_platform.c
index 99f9a89..0d0233e 100644
--- a/drivers/ata/ahci_platform.c
+++ b/drivers/ata/ahci_platform.c
@@ -26,7 +26,7 @@

 #define DRV_NAME "ahci"

-static const struct ata_port_info ahci_port_info = {
+static struct ata_port_info ahci_port_info = {
        .flags          = AHCI_FLAG_COMMON,
        .pio_mask       = ATA_PIO4,
        .udma_mask      = ATA_UDMA6,
@@ -41,6 +41,8 @@ static int ahci_probe(struct platform_device *pdev)
 {
        struct device *dev = &pdev->dev;
        struct ahci_host_priv *hpriv;
+       struct acpi_device_info *info;
+       acpi_status status;
        int rc;

        hpriv = ahci_platform_get_resources(pdev);
@@ -57,6 +59,15 @@ static int ahci_probe(struct platform_device *pdev)
        if (of_device_is_compatible(dev->of_node, "hisilicon,hisi-ahci"))
                hpriv->flags |= AHCI_HFLAG_NO_FBS | AHCI_HFLAG_NO_NCQ;

+       status = acpi_get_object_info(ACPI_HANDLE(dev), &info);
+       if (ACPI_SUCCESS(status)) {
+               if (info->valid & ACPI_VALID_HID) {
+                       if (!strcmp("APMC0D33", info->hardware_id.string))
+                               ahci_port_info.flags |= ATA_FLAG_NO_LPM;
+               }
+               ACPI_FREE(info);
+       }
+
        rc = ahci_platform_init_host(pdev, hpriv, &ahci_port_info,
                                     &ahci_platform_sht);
        if (rc)
--
1.8.3.1