Thread (19 messages) 19 messages, 4 authors, 2018-02-02

Re: [PATCH v6 4/6] iommu/arm-smmu: Add the device_link between masters and smmu

From: Vivek Gautam <hidden>
Date: 2018-02-01 08:53:11
Also in: dri-devel, linux-arm-msm, linux-iommu, linux-pm, lkml

Hi,


On 1/31/2018 6:39 PM, Robin Murphy wrote:
On 19/01/18 11:43, Vivek Gautam wrote:
quoted
From: Sricharan R <redacted>

Finally add the device link between the master device and
smmu, so that the smmu gets runtime enabled/disabled only when the
master needs it. This is done from add_device callback which gets
called once when the master is added to the smmu.
Don't we need to balance this with a device_link_del() in 
.remove_device (like exynos-iommu does)?
Right. Will add device_link_del() call. Thanks for pointing out.

regards
Vivek
Robin.
quoted
Signed-off-by: Sricharan R <redacted>
---
  drivers/iommu/arm-smmu.c | 11 +++++++++++
  1 file changed, 11 insertions(+)
diff --git a/drivers/iommu/arm-smmu.c b/drivers/iommu/arm-smmu.c
index 95478bfb182c..33bbcfedb896 100644
--- a/drivers/iommu/arm-smmu.c
+++ b/drivers/iommu/arm-smmu.c
@@ -1367,6 +1367,7 @@ static int arm_smmu_add_device(struct device *dev)
      struct arm_smmu_device *smmu;
      struct arm_smmu_master_cfg *cfg;
      struct iommu_fwspec *fwspec = dev->iommu_fwspec;
+    struct device_link *link;
      int i, ret;
        if (using_legacy_binding) {
@@ -1428,6 +1429,16 @@ static int arm_smmu_add_device(struct device 
*dev)
        pm_runtime_put_sync(smmu->dev);
  +    /*
+     * Establish the link between smmu and master, so that the
+     * smmu gets runtime enabled/disabled as per the master's
+     * needs.
+     */
+    link = device_link_add(dev, smmu->dev, DL_FLAG_PM_RUNTIME);
+    if (!link)
+        dev_warn(smmu->dev, "Unable to create device link between %s 
and %s\n",
+             dev_name(smmu->dev), dev_name(dev));
+
      return 0;
    out_cfg_free:
_______________________________________________
Freedreno mailing list
Freedreno@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/freedreno
Keyboard shortcuts
hback out one level
jnext message in thread
kprevious message in thread
ldrill in
Escclose help / fold thread tree
?toggle this help