SYSLINK:ipu-pm: Refactor ipu-pm module and fix suspend/resume

Also has compiler warning fix in AUXCLK request function

syslink: ipu_pm: refactor and cleanup functions

Including:
- ipu_pm module code was a reviewed and reworked to remove
  redundant code, simplify and enhance the implementation.
- Change ipu_notifications to receive proc_id.
- Add IOMMU_FAULT notifier callback function.
- Function to release all resources when IOMMU_FAULT event
  is received or when detaching, this is called in a
  workqueue to avoid calling context problems in the case of
  the FAULT event and called directly in the case of detaching.
- Add the possibility to select the SRC_CLK when requesting
  a gptimer.
- Add pr_debug traces for debugging purpose:
  Previosly all the errors when requesting/releasing
  resources were just reported to IPU using notify_event
  in the payload. Now kernel is printing errors/warnings/
  debug messages and also reporting the error back to IPU.
  This is needed because IPU could be dead and not able to
  see/print the error ipu_pm is reporting.

Change-Id: I22614bafc7cb7e3070d5bf565be6138fca5a809b
Signed-off-by: Miguel Vadillo <[email protected]>

syslink: ipu_pm: fix suspend/resume when no IPU image loaded

ipu_pm_drv_suspend and _resume were trying to notify ipu for
suspend/resume without cheking if an image was loaded leading
to an error in the suspend path.

Checking the handle to each proc before sending the notification
is avoiding this.

Suspend/resume is working now with/without an image loaded in IPU.

Change-Id: I55aca1674b1cdffba9fb3247e7da605b4082a521
Signed-off-by: Miguel Vadillo <[email protected]>

SYSLINK: IPU-PM: clean up warning in AUXCLK request function

clean up clk_disable( ) warning in AUXCLK request function:
ipu_pm_get_aux_clk( ).

Change-Id: I6bcc41e220f80f4e248bef65b3ed0fc379451d98
Signed-off-by: Paul Hunt <[email protected]>

SYSLINK: IPU-PM: restore IOMMU during ipu pm detach and mmu close

The IPU PM during the Ducati hibernation is shutting down the
IOMMU. If the User process that is using IOMMU is killed when the
Ducati is in hibernation state, the board hangs due to access to IOMMU during
resource cleanup.

The issue was observed when the Syslink daemon is killed with Ducati in
hibernation.

Change-Id: Ia5bd05fe382488c33ac858657f05aee9e22a48ee
Signed-off-by: Hari Kanigeri <[email protected]>

Author: Miguel Vadillo

arch/arm/mach-omap2/ipu_dev.c

@@ -41,14 +41,14 @@ static char *hwmod_state_strings[] = {
 	"_HWMOD_STATE_IDLE",
 	"_HWMOD_STATE_DISABLED",
 };
-static void print_hwmod_state(struct omap_hwmod *oh)
+static void print_hwmod_state(struct omap_hwmod *oh, char *desc)
 {
 	u32 _state = (u32) oh->_state;
-	pr_info("HWMOD name = %s\n", oh->name);
+	pr_debug("HWMOD name = %s\n", oh->name);
 	if (_state > _HWMOD_STATE_LAST)
 		WARN(1, "Illegal hwmod _state = %d\n", _state);
 	else
-		pr_info("state = %s\n", hwmod_state_strings[_state]);
+		pr_debug("%s state = %s\n", desc, hwmod_state_strings[_state]);
 }
 
 inline int ipu_pm_module_start(unsigned rsrc)
@@ -58,11 +58,11 @@ inline int ipu_pm_module_start(unsigned rsrc)
 
 	pd = ipupm_get_plat_data();
 
-	print_hwmod_state(pd[rsrc].oh);
+	print_hwmod_state(pd[rsrc].oh, "Previous");
 	ret = omap_device_enable(pd[rsrc].pdev);
 	if (ret)
 		pr_err("device enable failed %s", pd[rsrc].oh_name);
-
+	print_hwmod_state(pd[rsrc].oh, "New");
 	return ret;
 }
 EXPORT_SYMBOL(ipu_pm_module_start);
@@ -74,8 +74,10 @@ inline int ipu_pm_module_stop(unsigned rsrc)
 
 	pd = ipupm_get_plat_data();
 
-	print_hwmod_state(pd[rsrc].oh);
+	print_hwmod_state(pd[rsrc].oh, "Previous");
 	ret = omap_device_shutdown(pd[rsrc].pdev);
+	print_hwmod_state(pd[rsrc].oh, "New");
+
 	if (ret)
 		pr_err("device disable failed %s", pd[rsrc].oh_name);
 

arch/arm/mach-omap2/ipu_drv.c

@@ -201,24 +201,32 @@ static int ipu_pm_drv_suspend(struct device *dev)
 		 * BIOS timers could be saved locally or on Ducati
 		 */
 
-		/* call our notification function */
-		retval = ipu_pm_notifications(PM_SUSPEND, NULL);
-
 		/* FIXME: Currently sending SUSPEND is enough to send
 		 * Ducati to hibernate, save ctx can be called at this
 		 * point to save ctx and reset remote procs
 		 * Currently the save ctx process can be called using
 		 * which ever proc_id, maybe this will change when
 		 * Tesla support is added.
 		 */
-		/* sysm3 is handling hibernation of ducati currently */
-		ipu_pm_save_ctx(SYS_M3);
+		/* call notification function */
+		if (ipu_pm_get_handle(APP_M3)) {
+			retval = ipu_pm_notifications(APP_M3, PM_SUSPEND, NULL);
+			if (retval)
+				goto error;
+		}
+		if (ipu_pm_get_handle(SYS_M3)) {
+			retval = ipu_pm_notifications(SYS_M3, PM_SUSPEND, NULL);
+			if (retval)
+				goto error;
+			/* sysm3 is handling hibernation of ducati currently */
+			ipu_pm_save_ctx(SYS_M3);
+		}
 
 		/* return result, should be zero if all Ducati clients
 		 * returned zero else fail code
 		 */
 	}
-
+error:
 	return retval;
 }
 
@@ -234,13 +242,22 @@ static int ipu_pm_drv_resume(struct device *dev)
 		 */
 
 		/* call our notification function */
-		retval = ipu_pm_notifications(PM_RESUME, NULL);
+		if (ipu_pm_get_handle(APP_M3)) {
+			retval = ipu_pm_notifications(APP_M3, PM_RESUME, NULL);
+			if (retval)
+				goto error;
+		}
+		if (ipu_pm_get_handle(SYS_M3)) {
+			retval = ipu_pm_notifications(SYS_M3, PM_RESUME, NULL);
+			if (retval)
+				goto error;
+		}
 
 		/* return result, should be zero if all Ducati clients
 		 * returned zero else fail code
 		 */
 	}
-
+error:
 	return retval;
 }
 

drivers/dsp/syslink/devh/44xx/devh44xx.c

@@ -122,7 +122,8 @@ static int devh44xx_notifier_call(struct notifier_block *nb,
 		err = mutex_lock_interruptible(&local_gate);
 		if (err)
 			goto exit;
-		err = ipu_pm_notifications(PM_PID_DEATH, (void *)my_pid);
+		err = ipu_pm_notifications(APP_M3, PM_PID_DEATH,
+								(void *)my_pid);
 		if (err) {
 			pinfo->brd_state = DEVH_BRDST_ERROR;
 			if (!strcmp(pdata->name, "SysM3")) {