[PATCH 2/2] nvme: add quirk to not call disable function when suspending

From: AceLan Kao
Date: Mon Nov 05 2018 - 21:04:32 EST


Call nvme_dev_disable() function leads to the power consumption goes
up to 2.2 Watt during suspend-to-idle, and from SK hynix FE, they
suggest us to use its own APST feature to do the power management during
s2idle.
After D3 is diabled and nvme_dev_disable() is not called while
suspending, the power consumption drops to 0.77 Watt during s2idle.

Signed-off-by: AceLan Kao <acelan.kao@xxxxxxxxxxxxx>
---
drivers/nvme/host/nvme.h | 5 +++++
drivers/nvme/host/pci.c | 8 +++++++-
2 files changed, 12 insertions(+), 1 deletion(-)

diff --git a/drivers/nvme/host/nvme.h b/drivers/nvme/host/nvme.h
index cee79cb388af..35d260a4cf46 100644
--- a/drivers/nvme/host/nvme.h
+++ b/drivers/nvme/host/nvme.h
@@ -90,6 +90,11 @@ enum nvme_quirks {
* Set MEDIUM priority on SQ creation
*/
NVME_QUIRK_MEDIUM_PRIO_SQ = (1 << 7),
+
+ /*
+ * Do not disable nvme when suspending(s2idle)
+ */
+ NVME_QUIRK_NO_DISABLE = (1 << 8),
};

/*
diff --git a/drivers/nvme/host/pci.c b/drivers/nvme/host/pci.c
index c33bb201b884..586f3516e36b 100644
--- a/drivers/nvme/host/pci.c
+++ b/drivers/nvme/host/pci.c
@@ -31,6 +31,7 @@
#include <linux/io-64-nonatomic-lo-hi.h>
#include <linux/sed-opal.h>
#include <linux/pci-p2pdma.h>
+#include <linux/suspend.h>

#include "nvme.h"

@@ -2612,8 +2613,11 @@ static int nvme_suspend(struct device *dev)
{
struct pci_dev *pdev = to_pci_dev(dev);
struct nvme_dev *ndev = pci_get_drvdata(pdev);
+ struct nvme_ctrl *ctrl = &ndev->ctrl;
+
+ if (!(pm_suspend_via_s2idle() && (ctrl->quirks & NVME_QUIRK_NO_DISABLE)))
+ nvme_dev_disable(ndev, true);

- nvme_dev_disable(ndev, true);
return 0;
}

@@ -2716,6 +2720,8 @@ static const struct pci_device_id nvme_id_table[] = {
.driver_data = NVME_QUIRK_LIGHTNVM, },
{ PCI_DEVICE(0x1d1d, 0x2601), /* CNEX Granby */
.driver_data = NVME_QUIRK_LIGHTNVM, },
+ { PCI_DEVICE(0x1c5c, 0x1527), /* Sk Hynix */
+ .driver_data = NVME_QUIRK_NO_DISABLE, },
{ PCI_DEVICE_CLASS(PCI_CLASS_STORAGE_EXPRESS, 0xffffff) },
{ PCI_DEVICE(PCI_VENDOR_ID_APPLE, 0x2001) },
{ PCI_DEVICE(PCI_VENDOR_ID_APPLE, 0x2003) },
--
2.17.1