[Fwd: Re: [PATCH] tpm: interrupt clear fix]

[Kylene Jo Hall <kjhall@us.ibm.com>]

-------- Forwarded Message --------
From: Kylene Jo Hall <kjhall@us.ibm.com>
To: linux-os (Dick Johnson) <linux-os@analogic.com>
Cc: linux-kernel <linux-kernel@vger.kernel.org>, TPM Device Driver List
<tpmdd-devel@lists.sourceforge.net>, akpm@osdl.org
Subject: Re: [PATCH] tpm: interrupt clear fix
Date: Thu, 13 Jul 2006 12:24:36 -0700
Under stress testing I found that the interrupt is not always cleared.
This is a bug and this patch should go into 2.6.18 and 2.6.17.x.

On Thu, 2006-07-13 at 07:45 -0400, linux-os (Dick Johnson) wrote:

> PCI devices need a final read to flush all pending writes. Whatever
> mb() does, just hides the problem.


Signed-off-by: Kylene Hall <kjhall@us.ibm.com>
---

--- linux-2.6.18-rc1/drivers/char/tpm/tpm_tis.c	2006-07-13 14:46:39.727500500 -0500
+++ linux-2.6.18-rc1-tpm/drivers/char/tpm/tpm_tis.c	2006-07-13 14:47:33.878884750 -0500
@@ -424,6 +424,7 @@ static irqreturn_t tis_int_handler(int i
 	iowrite32(interrupt,
 		  chip->vendor.iobase +
 		  TPM_INT_STATUS(chip->vendor.locality));
+	ioread32(chip->vendor.iobase + TPM_INT_STATUS(chip->vendor.locality));
 	return IRQ_HANDLED;
 }