[POWERPC] PS3: os-area workqueue processing

Add a workqueue to the PS3 os-area support.  This is needed to
support writing updates to flash memory and to update the /proc
device tree entries from the timer tick interrupt context.

Signed-off-by: Geoff Levand <geoffrey.levand@am.sony.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>

1 files changed, 23 insertions, 0 deletions

diff --git a/arch/powerpc/platforms/ps3/os-area.c b/arch/powerpc/platforms/ps3/os-area.c
index f5112248802b..db311a147c28 100644
--- a/arch/powerpc/platforms/ps3/os-area.c
+++ b/arch/powerpc/platforms/ps3/os-area.c
@@ -20,6 +20,7 @@
 
 #include <linux/kernel.h>
 #include <linux/io.h>
+#include <linux/workqueue.h>
 
 #include <asm/lmb.h>
 
@@ -187,6 +188,28 @@ static int __init verify_header(const struct os_area_header *header)
 }
 
 /**
+ * os_area_queue_work_handler - Asynchronous write handler.
+ *
+ * An asynchronous write for flash memory and the device tree.  Do not
+ * call directly, use os_area_queue_work().
+ */
+
+static void os_area_queue_work_handler(struct work_struct *work)
+{
+	pr_debug(" -> %s:%d\n", __func__, __LINE__);
+
+	pr_debug(" <- %s:%d\n", __func__, __LINE__);
+}
+
+static void os_area_queue_work(void)
+{
+	static DECLARE_WORK(q, os_area_queue_work_handler);
+
+	wmb();
+	schedule_work(&q);
+}
+
+/**
  * ps3_os_area_save_params - Copy data from os area mirror to @saved_params.
  *
  * For the convenience of the guest, the HV makes a copy of the os area in