[PATCH 3.11 053/198] mei: me: read H_CSR after asserting reset

From: Luis Henriques
Date: Thu Jul 03 2014 - 06:09:52 EST


3.11.10.13 -stable review patch. If anyone has any objections, please let me know.

------------------

From: Tomas Winkler <tomas.winkler@xxxxxxxxx>

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@xxxxxxxxx>
Signed-off-by: Alexander Usyskin <alexander.usyskin@xxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
[ luis: backported to 3.11: adjusted context ]
Signed-off-by: Luis Henriques <luis.henriques@xxxxxxxxxxxxx>
---
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

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