omap: mbox: save, restore and off support

- Fix an issue related with the offsets of the registers
- Each user (Ducati, Tesla ...) should not have its own ctx
memory since the mbox module is one for all of them. A share
ctx is created to store the needed registers when saving.
- save_context function is saving just the irqs per user
currently that is the only thing needed.
- restore_context function is restoring just the irqs per user.
mbox_startup function is setting all the rest of the register
to the original state.
- Add a pm_qos constraint when calling the first get and release
it when the last put is calling, this is to support off mode.

Change-Id: I90cd5a8baa2c6343b6f3701a6accf14d5fcc3cf9
Signed-off-by: Miguel Vadillo <vadillo@ti.com>

1 files changed, 18 insertions, 2 deletions

diff --git a/arch/arm/plat-omap/mailbox.c b/arch/arm/plat-omap/mailbox.c
index 5eda382..a80e424 100644
--- a/arch/arm/plat-omap/mailbox.c
+++ b/arch/arm/plat-omap/mailbox.c
@@ -29,6 +29,7 @@
 #include <linux/kfifo.h>
 #include <linux/err.h>
 #include <linux/notifier.h>
+#include <linux/pm_qos_params.h>
 
 #include <plat/mailbox.h>
 
@@ -36,6 +37,10 @@ static struct omap_mbox **mboxes;
 
 static int mbox_configured;
 static DEFINE_MUTEX(mbox_configured_lock);
+struct pm_qos_request_list mbox_qos_request;
+
+#define SET_MPU_CORE_CONSTRAINT 10
+#define CLEAR_MPU_CORE_CONSTRAINT -1
 
 static unsigned int mbox_kfifo_size = CONFIG_OMAP_MBOX_KFIFO_SIZE;
 module_param(mbox_kfifo_size, uint, S_IRUGO);
@@ -251,6 +256,8 @@ static int omap_mbox_startup(struct omap_mbox *mbox)
 
 	mutex_lock(&mbox_configured_lock);
 	if (!mbox_configured++) {
+		pm_qos_update_request(&mbox_qos_request,
+					SET_MPU_CORE_CONSTRAINT);
 		if (likely(mbox->ops->startup)) {
 			ret = mbox->ops->startup(mbox);
 			if (unlikely(ret))
@@ -294,7 +301,9 @@ fail_request_irq:
 		mbox->ops->shutdown(mbox);
 	mbox->use_count--;
 fail_startup:
-	mbox_configured--;
+	if (!--mbox_configured)
+		pm_qos_update_request(&mbox_qos_request,
+					 CLEAR_MPU_CORE_CONSTRAINT);
 	mutex_unlock(&mbox_configured_lock);
 	return ret;
 }
@@ -312,8 +321,11 @@ static void omap_mbox_fini(struct omap_mbox *mbox)
 	}
 
 	if (likely(mbox->ops->shutdown)) {
-		if (!--mbox_configured)
+		if (!--mbox_configured) {
 			mbox->ops->shutdown(mbox);
+			pm_qos_update_request(&mbox_qos_request,
+						CLEAR_MPU_CORE_CONSTRAINT);
+		}
 	}
 
 	mutex_unlock(&mbox_configured_lock);
@@ -396,6 +408,7 @@ int omap_mbox_unregister(void)
 
 	for (i = 0; mboxes[i]; i++)
 		device_unregister(mboxes[i]->dev);
+
 	mboxes = NULL;
 	return 0;
 }
@@ -414,6 +427,8 @@ static int __init omap_mbox_init(void)
 	mbox_kfifo_size = max_t(unsigned int, mbox_kfifo_size,
 							sizeof(mbox_msg_t));
 
+	pm_qos_add_request(&mbox_qos_request, PM_QOS_CPU_DMA_LATENCY,
+						PM_QOS_DEFAULT_VALUE);
 	return 0;
 }
 subsys_initcall(omap_mbox_init);
@@ -421,6 +436,7 @@ subsys_initcall(omap_mbox_init);
 static void __exit omap_mbox_exit(void)
 {
 	class_unregister(&omap_mbox_class);
+	pm_qos_remove_request(&mbox_qos_request);
 }
 module_exit(omap_mbox_exit);