omap iommu: add functionality to get TLB miss interrupt

In order to enable TLB miss interrupt, the TWL should be
disabled. This patch provides the functionality to get the
MMU fault interrupt for a TLB miss in the cases where the
users are working with the locked TLB entries and with TWL
disabled.
New interface is added to select twl and to enable TLB miss
interrupt.

Signed-off-by: Hari Kanigeri <h-kanigeri2@ti.com>
Signed-off-by: Ramesh Gupta <grgupta@ti.com>
Signed-off-by: Hiroshi Doyu <Hiroshi.DOYU@nokia.com>

1 files changed, 17 insertions, 0 deletions

diff --git a/arch/arm/plat-omap/iommu.c b/arch/arm/plat-omap/iommu.c
index 341c48179ee0..688ae66bb8fc 100644
--- a/arch/arm/plat-omap/iommu.c
+++ b/arch/arm/plat-omap/iommu.c
@@ -370,6 +370,23 @@ void flush_iotlb_all(struct iommu *obj)
 }
 EXPORT_SYMBOL_GPL(flush_iotlb_all);
 
+/**
+ * iommu_set_twl - enable/disable table walking logic
+ * @obj:        target iommu
+ * @on:         enable/disable
+ *
+ * Function used to enable/disable TWL. If one wants to work
+ * exclusively with locked TLB entries and receive notifications
+ * for TLB miss then call this function to disable TWL.
+ */
+void iommu_set_twl(struct iommu *obj, bool on)
+{
+        clk_enable(obj->clk);
+        arch_iommu->set_twl(obj, on);
+        clk_disable(obj->clk);
+}
+EXPORT_SYMBOL_GPL(iommu_set_twl);
+
 #if defined(CONFIG_OMAP_IOMMU_DEBUG_MODULE)
 
 ssize_t iommu_dump_ctx(struct iommu *obj, char *buf, ssize_t bytes)