linux-kernel - [char-misc 3.11] mei: me: fix hardware reset flow

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [day] [month] [year] [list]

Message-Id: <1375173718-9982-1-git-send-email-tomas.winkler@intel.com>
Date:	Tue, 30 Jul 2013 11:41:58 +0300
From:	Tomas Winkler <tomas.winkler@...el.com>
To:	gregkh@...uxfoundation.org
Cc:	arnd@...db.de, linux-kernel@...r.kernel.org,
	Tomas Winkler <tomas.winkler@...el.com>,
	Shuah Khan <huah.kh@...sung.com>,
	Konstantin Khlebnikov <khlebnikov@...nvz.org>
Subject: [char-misc 3.11] mei: me: fix hardware reset flow

Both H_IS and H_IE needs to be set to receive H_RDY 
interrupt

1. Assert H_IS to clear the interrupts during hw reset
and use mei_me_reg_write instead of mei_hcsr_set as the later
strips down the H_IS

2. fix interrupt disablement embarrassing typo
  hcsr |= ~H_IE -> hcsr &= ~H_IE;
this will remove the unwanted interrupt on power down

3. remove useless debug print outs

Cc: Shuah Khan <huah.kh@...sung.com>
Cc: Konstantin Khlebnikov <khlebnikov@...nvz.org>
Signed-off-by: Tomas Winkler <tomas.winkler@...el.com>
---

Hope this finally resolve the ME reset issue

 drivers/misc/mei/hw-me.c | 9 +++------
 1 file changed, 3 insertions(+), 6 deletions(-)

diff --git a/drivers/misc/mei/hw-me.c b/drivers/misc/mei/hw-me.c
index b22c7e2..3412adc 100644
--- a/drivers/misc/mei/hw-me.c
+++ b/drivers/misc/mei/hw-me.c
@@ -176,21 +176,18 @@ static int mei_me_hw_reset(struct mei_device *dev, bool intr_enable)
 	struct mei_me_hw *hw = to_me_hw(dev);
 	u32 hcsr = mei_hcsr_read(hw);
 
-	dev_dbg(&dev->pdev->dev, "before reset HCSR = 0x%08x.\n", hcsr);
-
-	hcsr |= (H_RST | H_IG);
+	hcsr |= H_RST | H_IG | H_IS;
 
 	if (intr_enable)
 		hcsr |= H_IE;
 	else
-		hcsr |= ~H_IE;
+		hcsr &= ~H_IE;
 
-	mei_hcsr_set(hw, hcsr);
+	mei_me_reg_write(hw, H_CSR, hcsr);
 
 	if (dev->dev_state == MEI_DEV_POWER_DOWN)
 		mei_me_hw_reset_release(dev);
 
-	dev_dbg(&dev->pdev->dev, "current HCSR = 0x%08x.\n", mei_hcsr_read(hw));
 	return 0;
 }
 
-- 
1.8.1.2

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/