[3.11.y.z extended stable] Patch "mei: me: read H_CSR after asserting reset" has been added to staging queue

[Luis Henriques]

This is a note to let you know that I have just added a patch titled

    mei: me: read H_CSR after asserting reset

to the linux-3.11.y-queue branch of the 3.11.y.z extended stable tree 
which can be found at:

 http://kernel.ubuntu.com/git?p=ubuntu/linux.git;a=shortlog;h=refs/heads/linux-3.11.y-queue

If you, or anyone else, feels it should not be added to this tree, please 
reply to this email.

For more information about the 3.11.y.z tree, see
https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable

Thanks.
-Luis

------

>From e51c8c238e0755898a68dd0dd458ec7ad4a24aba Mon Sep 17 00:00:00 2001
From: Tomas Winkler <tomas.winkler at intel.com>
Date: Mon, 12 May 2014 12:19:41 +0300
Subject: mei: me: read H_CSR after asserting reset

commit c40765d919d25d2d44d99c4ce39e48808f137e1e upstream.

According the spec the host should read H_CSR again
after asserting reset H_RST to ensure that reset was
read by the firmware

Signed-off-by: Tomas Winkler <tomas.winkler at intel.com>
Signed-off-by: Alexander Usyskin <alexander.usyskin at intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh at linuxfoundation.org>
[ luis: backported to 3.11: adjusted context ]
Signed-off-by: Luis Henriques <luis.henriques at canonical.com>
---
 drivers/misc/mei/hw-me.c | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/drivers/misc/mei/hw-me.c b/drivers/misc/mei/hw-me.c
index 6cba26d9465f..e2ca1574d22a 100644
--- a/drivers/misc/mei/hw-me.c
+++ b/drivers/misc/mei/hw-me.c
@@ -186,6 +186,18 @@ static int mei_me_hw_reset(struct mei_device *dev, bool intr_enable)
 	dev->recvd_hw_ready = false;
 	mei_me_reg_write(hw, H_CSR, hcsr);

+	/*
+	 * Host reads the H_CSR once to ensure that the
+	 * posted write to H_CSR completes.
+	 */
+	hcsr = mei_hcsr_read(hw);
+
+	if ((hcsr & H_RST) == 0)
+		dev_warn(&dev->pdev->dev, "H_RST is not set = 0x%08X", hcsr);
+
+	if ((hcsr & H_RDY) == H_RDY)
+		dev_warn(&dev->pdev->dev, "H_RDY is not cleared 0x%08X", hcsr);
+
 	if (dev->dev_state == MEI_DEV_POWER_DOWN)
 		mei_me_hw_reset_release(dev);

--
1.9.1