[PATCH 3.10 39/46] mei: me: read H_CSR after asserting reset

Greg Kroah-Hartman
2014-07-04T22:25:39Z

From: Tomas Winkler <tomas.winkler@intel.com>

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@intel.com>
Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
drivers/misc/mei/hw-me.c | 14 +++++++++++++-
1 file changed, 13 insertions(+), 1 deletion(-)

--- a/drivers/misc/mei/hw-me.c
+++ b/drivers/misc/mei/hw-me.c
@@ -186,7 +186,19 @@ static void mei_me_hw_reset(struct mei_d
dev->recvd_hw_ready = false;
mei_me_reg_write(hw, H_CSR, hcsr);

- if (dev->dev_state == MEI_DEV_POWER_DOWN)
+ /*
+ * 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 (intr_enable == false)
mei_me_hw_reset_release(dev);

dev_dbg(&dev->pdev->dev, "current HCSR = 0x%08x.\n", mei_hcsr_read(hw));