On 7/10/2013 7:01 PM, Seungwon Jeon wrote:
On Tue, July 09, 2013, Sujit Reddy Thumma wrote:
Add runtime PM helpers to suspend/resume UFS controller at runtime.
Enable runtime PM by default for pci and platform drivers as the
initialized hardware can suspend if it is not used after bootup.
Signed-off-by: Sujit Reddy Thumma <sthumma@xxxxxxxxxxxxxx>
---
drivers/scsi/ufs/ufshcd-pci.c | 65 ++++++++++++++++++++++++++++++++++---
drivers/scsi/ufs/ufshcd-pltfrm.c | 51 +++++++++++++++++++++++++++++-
drivers/scsi/ufs/ufshcd.c | 8 +++++
3 files changed, 117 insertions(+), 7 deletions(-)
diff --git a/drivers/scsi/ufs/ufshcd-pci.c b/drivers/scsi/ufs/ufshcd-pci.c
index 48be39a..7bd8faa 100644
--- a/drivers/scsi/ufs/ufshcd-pci.c
+++ b/drivers/scsi/ufs/ufshcd-pci.c
@@ -35,6 +35,7 @@
#include "ufshcd.h"
#include <linux/pci.h>
+#include <linux/pm_runtime.h>
#ifdef CONFIG_PM
/**
@@ -44,7 +45,7 @@
*
* Returns -ENOSYS
*/
-static int ufshcd_pci_suspend(struct pci_dev *pdev, pm_message_t state)
+static int ufshcd_pci_suspend(struct device *dev)
{
/*
* TODO:
@@ -61,7 +62,7 @@ static int ufshcd_pci_suspend(struct pci_dev *pdev, pm_message_t state)
*
* Returns -ENOSYS
*/
-static int ufshcd_pci_resume(struct pci_dev *pdev)
+static int ufshcd_pci_resume(struct device *dev)
{
/*
* TODO:
@@ -71,8 +72,48 @@ static int ufshcd_pci_resume(struct pci_dev *pdev)
return -ENOSYS;
}
+#else
+#define ufshcd_pci_suspend NULL
+#define ufshcd_pci_resume NULL
#endif /* CONFIG_PM */
+#ifdef CONFIG_PM_RUNTIME
+static int ufshcd_pci_runtime_suspend(struct device *dev)
+{
+ struct pci_dev *pdev = container_of(dev, struct pci_dev, dev);
+ struct ufs_hba *hba = pci_get_drvdata(pdev);
Can be replaced:
struct ufs_hba *hba = dev_get_drvdata(dev);
Yes.
+
+ if (!hba)
+ return 0;
+
+ return ufshcd_runtime_suspend(hba);
+}
+static int ufshcd_pci_runtime_resume(struct device *dev)
+{
+ struct pci_dev *pdev = container_of(dev, struct pci_dev, dev);
+ struct ufs_hba *hba = pci_get_drvdata(pdev);
Same as above.
Okay.
+
+ if (!hba)
+ return 0;
+
+ return ufshcd_runtime_resume(hba);
+}
+static int ufshcd_pci_runtime_idle(struct device *dev)
+{
+ struct pci_dev *pdev = container_of(dev, struct pci_dev, dev);
+ struct ufs_hba *hba = pci_get_drvdata(pdev);
Same as above.
Okay.
+
+ if (!hba)
+ return 0;
+
+ return ufshcd_runtime_idle(hba);
+}
+#else /* !CONFIG_PM_RUNTIME */
+#define ufshcd_pci_runtime_suspend NULL
+#define ufshcd_pci_runtime_resume NULL
+#define ufshcd_pci_runtime_idle NULL
+#endif /* CONFIG_PM_RUNTIME */
+
/**
* ufshcd_pci_shutdown - main function to put the controller in reset state
* @pdev: pointer to PCI device handle
@@ -91,6 +132,9 @@ static void ufshcd_pci_remove(struct pci_dev *pdev)
{
struct ufs_hba *hba = pci_get_drvdata(pdev);
+ pm_runtime_forbid(&pdev->dev);
+ pm_runtime_get_noresume(&pdev->dev);
+
disable_irq(pdev->irq);
ufshcd_remove(hba);
pci_release_regions(pdev);
@@ -168,6 +212,8 @@ ufshcd_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id)
}
pci_set_drvdata(pdev, hba);
+ pm_runtime_put_noidle(&pdev->dev);
+ pm_runtime_allow(&pdev->dev);
return 0;
@@ -182,6 +228,14 @@ out_error:
return err;
}
+static const struct dev_pm_ops ufshcd_pci_pm_ops = {
+ .suspend = ufshcd_pci_suspend,
+ .resume = ufshcd_pci_resume,
+ .runtime_suspend = ufshcd_pci_runtime_suspend,
+ .runtime_resume = ufshcd_pci_runtime_resume,
+ .runtime_idle = ufshcd_pci_runtime_idle,
+};
+
static DEFINE_PCI_DEVICE_TABLE(ufshcd_pci_tbl) = {
{ PCI_VENDOR_ID_SAMSUNG, 0xC00C, PCI_ANY_ID, PCI_ANY_ID, 0, 0, 0 },
{ } /* terminate list */
@@ -195,10 +249,9 @@ static struct pci_driver ufshcd_pci_driver = {
.probe = ufshcd_pci_probe,
.remove = ufshcd_pci_remove,
.shutdown = ufshcd_pci_shutdown,
-#ifdef CONFIG_PM
- .suspend = ufshcd_pci_suspend,
- .resume = ufshcd_pci_resume,
-#endif
+ .driver = {
+ .pm = &ufshcd_pci_pm_ops
+ },
};
module_pci_driver(ufshcd_pci_driver);
diff --git a/drivers/scsi/ufs/ufshcd-pltfrm.c b/drivers/scsi/ufs/ufshcd-pltfrm.c
index c42db40..b1f2605 100644
--- a/drivers/scsi/ufs/ufshcd-pltfrm.c
+++ b/drivers/scsi/ufs/ufshcd-pltfrm.c
@@ -34,6 +34,7 @@
*/
#include <linux/platform_device.h>
+#include <linux/pm_runtime.h>
#include "ufshcd.h"
@@ -87,6 +88,43 @@ static int ufshcd_pltfrm_resume(struct device *dev)
#define ufshcd_pltfrm_resume NULL
#endif
+#ifdef CONFIG_PM_RUNTIME
+static int ufshcd_pltfrm_runtime_suspend(struct device *dev)
+{
+ struct platform_device *pdev = to_platform_device(dev);
+ struct ufs_hba *hba = platform_get_drvdata(pdev);
Same as above.
Okay.
+
+ if (!hba)
+ return 0;
+
+ return ufshcd_runtime_suspend(hba);
+}
+static int ufshcd_pltfrm_runtime_resume(struct device *dev)
+{
+ struct platform_device *pdev = to_platform_device(dev);
+ struct ufs_hba *hba = platform_get_drvdata(pdev);
Same as above.
Okay.
+
+ if (!hba)
+ return 0;
+
+ return ufshcd_runtime_resume(hba);
+}
+static int ufshcd_pltfrm_runtime_idle(struct device *dev)
+{
+ struct platform_device *pdev = to_platform_device(dev);
+ struct ufs_hba *hba = platform_get_drvdata(pdev);
Same as above.
Okay.
+
+ if (!hba)
+ return 0;
+
+ return ufshcd_runtime_idle(hba);
+}
+#else /* !CONFIG_PM_RUNTIME */
+#define ufshcd_pltfrm_runtime_suspend NULL
+#define ufshcd_pltfrm_runtime_resume NULL
+#define ufshcd_pltfrm_runtime_idle NULL
+#endif /* CONFIG_PM_RUNTIME */
+
/**
* ufshcd_pltfrm_probe - probe routine of the driver
* @pdev: pointer to Platform device handle
@@ -122,14 +160,20 @@ static int ufshcd_pltfrm_probe(struct platform_device *pdev)
goto out;
}
+ pm_runtime_set_active(&pdev->dev);
+ pm_runtime_enable(&pdev->dev);
+
err = ufshcd_init(dev, &hba, mmio_base, irq);
if (err) {
dev_err(dev, "Intialization failed\n");
- goto out;
+ goto out_disable_rpm;
}
platform_set_drvdata(pdev, hba);
+out_disable_rpm:
+ pm_runtime_disable(&pdev->dev);
+ pm_runtime_set_suspended(&pdev->dev);
out:
return err;
}
@@ -144,6 +188,8 @@ static int ufshcd_pltfrm_remove(struct platform_device *pdev)
{
struct ufs_hba *hba = platform_get_drvdata(pdev);
+ pm_runtime_get_sync(&(pdev)->dev);
+
disable_irq(hba->irq);
ufshcd_remove(hba);
return 0;
@@ -157,6 +203,9 @@ static const struct of_device_id ufs_of_match[] = {
static const struct dev_pm_ops ufshcd_dev_pm_ops = {
.suspend = ufshcd_pltfrm_suspend,
.resume = ufshcd_pltfrm_resume,
+ .runtime_suspend = ufshcd_pltfrm_runtime_suspend,
+ .runtime_resume = ufshcd_pltfrm_runtime_resume,
+ .runtime_idle = ufshcd_pltfrm_runtime_idle,
};
static struct platform_driver ufshcd_pltfrm_driver = {
diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
index a25de66..af7d01d 100644
--- a/drivers/scsi/ufs/ufshcd.c
+++ b/drivers/scsi/ufs/ufshcd.c
@@ -2230,6 +2230,7 @@ static void ufshcd_exception_event_handler(struct work_struct *work)
u32 status = 0;
hba = container_of(work, struct ufs_hba, eeh_work);
+ pm_runtime_get_sync(hba->dev);
err = ufshcd_get_ee_status(hba, &status);
if (err) {
dev_err(hba->dev, "%s: failed to get exception status %d\n",
@@ -2245,6 +2246,7 @@ static void ufshcd_exception_event_handler(struct work_struct *work)
__func__, err);
}
out:
+ pm_runtime_put_sync(hba->dev);
In ufshcd_urgent_bkops, ufshcd_enable_auto_bkops will be executed.
That should be still fine. We have necessary checks in
ufshcd_enable_auto_bkops() to skip enabling if already enabled.
return;
}
@@ -2257,9 +2259,11 @@ static void ufshcd_fatal_err_handler(struct work_struct *work)
struct ufs_hba *hba;
hba = container_of(work, struct ufs_hba, feh_workq);
+ pm_runtime_get_sync(hba->dev);
/* check if reset is already in progress */
if (hba->ufshcd_state != UFSHCD_STATE_RESET)
ufshcd_do_reset(hba);
+ pm_runtime_put_sync(hba->dev);
}
/**
@@ -2562,6 +2566,7 @@ static void ufshcd_async_scan(void *data, async_cookie_t cookie)
hba->auto_bkops_enabled = false;
In the end of 'ufshcd_init', pm_runtime_get_sync is called, hence auto_bkops_enabled may has false.
'auto_bkops_enabled = false' is needed?
The device may undergo reset before this, and so the internal device
flag may be reset to default (which is auto bkops enabled). The two
steps here - auto_bkops_enabled = false and ufshcd_enabled_auto_bkops()
ensure that s/w variables are aligned with h/w state.
ufshcd_enable_auto_bkops(hba);
Should 'ufshcd_enable_auto_bkops' be done here?
Not really needed. But just to make sure that bootloader didn't mess
up with it and the s/w variables are still pointing that auto_bkops is
disabled.
scsi_scan_host(hba->host);
+ pm_runtime_put_sync(hba->dev);
Practically, after pm_runtime_put_sync, ufshcd_enable_auto_bkops will be executed.
Then, it's duplication of ufshcd_enable_auto_bkops?
ufshcd_enable_auto_bkops is already done above.
ufshcd_enable_auto_bkops() has necessary checks to make sure that we
are not re-enabling if already enabled.
One thing to note here is that pm_runtime_get_sync() and put_sync()
are independent of the bkops status. The runtime PM make sures that
after device idle'd suspend is triggered. What we do in suspend routine
is not of a concern. Moreover, pm_runtime_get_sync() calls are just
dummy calls when CONFIG_RUNTIME_PM is disabled so we can't assume
anything with that and make the sequence complex.
And actual routine of scsi_scan_host performs asynchronously.
That means it's not completed. So, pm_runtime_put_sync looks like improper here.
After this operation, the device is sure to respond to any command
including those required for bkops. So put_sync is proper here.
If there is any new command issued to the controller as part
of scsi_scan_host() and the host is already suspended it will be
resumed, we are not breaking the parent-child relation ship so any new
device when added as a child triggers runtime resume for parent (if
suspended).
out:
return;
}
@@ -2783,6 +2788,9 @@ int ufshcd_init(struct device *dev, struct ufs_hba **hba_handle,
*hba_handle = hba;
+ /* Hold auto suspend until async scan completes */
What's meaning of comment?
We haven't yet initialized the device so runtime PM suspned/resume may
fail. Until async scan is scheduled we take PM reference count to make
sure device is not suspended inbetween.
Thanks,
Seungwon Jeon
+ pm_runtime_get_sync(dev);
+
async_schedule(ufshcd_async_scan, hba);
return 0;
--
QUALCOMM INDIA, on behalf of Qualcomm Innovation Center, Inc. is a member
of Code Aurora Forum, hosted by The Linux Foundation.
--
To unsubscribe from this list: send the line "unsubscribe linux-scsi" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
--
Regards,
Sujit
--
To unsubscribe from this list: send the line "unsubscribe linux-scsi" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
