video: tegra: host: use runtime pm for clock management

- use runtime pm for clock management of host1x
and its clients thus replacing ACM
- start a delayed worker after disabling the clock
if module supports power gating
- in its timeout handler power gate the module after saving
its context for next submit
- use auto-suspend mode of runtime pm for clock management
- pm core seems to keep a ref count on runtime pm thus
we cannot use runtime pm's usage_count as an idicator
of module idle during suspend
- do not use runtime pm call-backs during system suspend.
instead manage the clocks directly for context save of
modules that support it
- enable runtime pm only during boot-up as pm core disables
it before suspending the device and enables it after resume

for bug 887332

Change-Id: I3b30643e8e75c13684cf4edaaae4429c3a18d6eb
Signed-off-by: Mayuresh Kulkarni <mkulkarni@nvidia.com>
Reviewed-on: http://git-master/r/79186
Reviewed-by: Terje Bergstrom <tbergstrom@nvidia.com>

1 files changed, 25 insertions, 3 deletions

diff --git a/drivers/video/tegra/host/dev.c b/drivers/video/tegra/host/dev.c
index 4cd1e4eaf843..c75448021484 100644
--- a/drivers/video/tegra/host/dev.c
+++ b/drivers/video/tegra/host/dev.c
@@ -35,7 +35,7 @@
 #include <linux/hrtimer.h>
 #define CREATE_TRACE_POINTS
 #include <trace/events/nvhost.h>
-
+#include <linux/pm_runtime.h>
 #include <linux/io.h>
 
 #include <linux/nvhost.h>
@@ -984,20 +984,24 @@ static int __devinit nvhost_probe(struct platform_device *pdev)
 	if (err)
 		goto fail;
 
+	pm_runtime_enable(&hostdev.dev);
 	err = nvhost_module_init(&hostdev);
 	if (err)
 		goto fail;
 
 	for (i = 0; i < host->nb_channels; i++) {
 		struct nvhost_channel *ch = &host->channels[i];
+		pm_runtime_enable(&ch->dev->dev);
 		nvhost_module_init(ch->dev);
 	}
 
 	platform_set_drvdata(pdev, host);
 
-	clk_enable(host->dev->clk[0]);
+	for (i = 0; i < host->dev->num_clks; i++)
+		clk_enable(host->dev->clk[i]);
 	nvhost_syncpt_reset(&host->syncpt);
-	clk_disable(host->dev->clk[0]);
+	for (i = 0; i < host->dev->num_clks; i++)
+		clk_disable(host->dev->clk[i]);
 
 	nvhost_debug_init(host);
 
@@ -1038,7 +1042,25 @@ static int nvhost_suspend(struct platform_device *pdev, pm_message_t state)
 
 static int nvhost_resume(struct platform_device *pdev)
 {
+	int i;
+	struct nvhost_master *host = platform_get_drvdata(pdev);
+
 	dev_info(&pdev->dev, "resuming\n");
+
+	for (i = 0; i < host->dev->num_clks; i++)
+		clk_enable(host->dev->clk[i]);
+	if (host->dev->finalize_poweron)
+		host->dev->finalize_poweron(host->dev);
+	for (i = 0; i < host->dev->num_clks; i++)
+		clk_disable(host->dev->clk[i]);
+
+	/* enable runtime pm for host1x */
+	nvhost_module_resume(host->dev);
+
+	/* enable runtime pm for clients */
+	for (i = 0; i < host->nb_channels; i++)
+		nvhost_module_resume(host->channels[i].dev);
+
 	return 0;
 }