Hi,
On 27-08-18 20:47, Suman Tripathi wrote:
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 <stripathi@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: Rameshwar Prasad Sahu <rameshwar.sahu@xxxxxxxxxxxxxxxxxxx>
Thank you for the patch. 2 remarks:
1) The ata code is maintained by Jens Axboe (added to the Cc) now, this
is a very recent change, which still has to hit MAINTAINERS
2) See below
---
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,
Please do not remove const here, if you need to make a shared info struct
like this non const you are usually doing something wrong (see below).
@@ -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)
The normal way to get specific behavior for a specific ACPI HID is
to put the HID in the ahci_acpi_match table and use the acpi_device_id
field to pass some flags (or a pointer).
So the proper way to fix this is to do something like this:
1) Add:
static const struct ata_port_info ahci_port_info_nolpm = {
.flags = AHCI_FLAG_COMMON | ATA_FLAG_NO_LPM,
.pio_mask = ATA_PIO4,
.udma_mask = ATA_UDMA6,
.port_ops = &ahci_platform_ops,
};
2) Modify ahci_acpi_match table to:
static const struct acpi_device_id ahci_acpi_match[] = {
{ "APMC0D33", (unsigned long)&ahci_port_info_nolpm },
{ ACPI_DEVICE_CLASS(PCI_CLASS_STORAGE_SATA_AHCI, 0xffffff) },
{},
};
3) In ahci_probe() do:
const struct ata_port_info *port;
...
port = acpi_device_get_match_data(dev);
if (!port)
port = &ahci_port_info;
rc = ahci_platform_init_host(pdev, hpriv, port, &ahci_platform_sht);
Regards,
Hans
