omap: iommu: program constraints based on platform data

IOMMU driver requests and releases constraints in iommu_get
and iommu_put respectively. These constraints are actually
needed only on OMAP4 and beyond for sub-systems that have
an AMMU. The current driver code has these values hard-coded
for all the chips.

A new platform data field has been added now for the constraints
values, and this allows the values to be programmed based on
the OMAP chip and also allow a unique value if needed for each
iommu instance.

The logic in IOMMU driver code is adjusted to request the
constraints only if the relevant platform data field is set.

Change-Id: Iab18cbdde1d7fa7507dbff0b9512c8577b42fefd
Signed-off-by: Subramaniam C.A <subramaniam.ca@ti.com>
Signed-off-by: Suman Anna <s-anna@ti.com>

2 files changed, 19 insertions, 15 deletions

diff --git a/arch/arm/plat-omap/include/plat/iommu.h b/arch/arm/plat-omap/include/plat/iommu.h
index ed33ddf..59bc69c 100644
--- a/arch/arm/plat-omap/include/plat/iommu.h
+++ b/arch/arm/plat-omap/include/plat/iommu.h
@@ -56,6 +56,7 @@ struct iommu {
 	u32 da_end;
 	struct platform_device *pdev;
 	struct pm_qos_request_list *qos_request;
+	unsigned int pm_constraint;
 	void *secure_ttb;
 	bool secure_mode;
 };
@@ -114,6 +115,7 @@ struct iommu_platform_data {
 	u32 da_start;
 	u32 da_end;
 	int irq;
+	unsigned int pm_constraint;
 	void __iomem *io_base;
 };
 
diff --git a/arch/arm/plat-omap/iommu.c b/arch/arm/plat-omap/iommu.c
index f82db49..b3c575c 100644
--- a/arch/arm/plat-omap/iommu.c
+++ b/arch/arm/plat-omap/iommu.c
@@ -31,10 +31,6 @@
 	     (__i < (n)) && (cr = __iotlb_read_cr((obj), __i), true);	\
 	     __i++)
 
-#define SET_MPU_CORE_CONSTRAINT	10
-#define SET_DSP_CONSTRAINT	10
-#define CLEAR_CONSTRAINT	-1
-
 /* accommodate the difference between omap1 and omap2/3 */
 static const struct iommu_functions *arch_iommu;
 
@@ -857,13 +853,13 @@ static void _set_latency_cstr(struct iommu *obj, bool set)
 {
 	int val;
 
-	if (!strcmp(obj->name, "ducati")) {
-		val = set ? SET_MPU_CORE_CONSTRAINT : CLEAR_CONSTRAINT;
+	val = set ? obj->pm_constraint : PM_QOS_DEFAULT_VALUE;
+	if (!strcmp(obj->name, "ducati"))
 		pm_qos_update_request(obj->qos_request, val);
-	} else if (!strcmp(obj->name, "tesla")) {
-		val = set ? SET_DSP_CONSTRAINT : CLEAR_CONSTRAINT;
-		omap_pm_set_max_dev_wakeup_lat(obj->dev, obj->dev, val);
-	}
+	else if (!strcmp(obj->name, "tesla"))
+		omap_pm_set_max_dev_wakeup_lat(obj->dev,
+				obj->dev, val);
+
 	return;
 }
 
@@ -887,12 +883,13 @@ struct iommu *iommu_get(const char *name)
 	mutex_lock(&obj->iommu_lock);
 
 	if (obj->refcount++ == 0) {
-		_set_latency_cstr(obj, true);
+		if (obj->pm_constraint)
+			_set_latency_cstr(obj, true);
+
 		err = iommu_enable(obj);
-		if (err) {
-			_set_latency_cstr(obj, false);
+		if (err)
 			goto err_enable;
-		}
+
 		flush_iotlb_all(obj);
 	}
 
@@ -908,6 +905,9 @@ err_module:
 	if (obj->refcount == 1)
 		iommu_disable(obj);
 err_enable:
+	if (obj->pm_constraint)
+		_set_latency_cstr(obj, false);
+
 	obj->refcount--;
 	mutex_unlock(&obj->iommu_lock);
 	return ERR_PTR(err);
@@ -933,7 +933,8 @@ void iommu_put(struct iommu *obj)
 
 	if (--obj->refcount == 0) {
 		iommu_disable(obj);
-		_set_latency_cstr(obj, false);
+		if (obj->pm_constraint)
+			_set_latency_cstr(obj, false);
 	}
 
 	module_put(obj->owner);
@@ -1016,6 +1017,7 @@ static int __devinit omap_iommu_probe(struct platform_device *pdev)
 	obj->ctx = (void *)obj + sizeof(*obj);
 	obj->da_start = pdata->da_start;
 	obj->da_end = pdata->da_end;
+	obj->pm_constraint = pdata->pm_constraint;
 
 	mutex_init(&obj->iommu_lock);
 	mutex_init(&obj->mmap_lock);