Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752149Ab3CRJGd (ORCPT ); Mon, 18 Mar 2013 05:06:33 -0400 Received: from smtp1.infineon.com ([203.161.181.8]:53097 "EHLO smtp1.infineon.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751585Ab3CRJGa convert rfc822-to-8bit (ORCPT ); Mon, 18 Mar 2013 05:06:30 -0400 X-Greylist: delayed 610 seconds by postgrey-1.27 at vger.kernel.org; Mon, 18 Mar 2013 05:06:30 EDT X-SBRS: None From: To: , CC: , , , Subject: RE: [tpmdd-devel] [PATCH] TPM: Retry SaveState command in suspend path Thread-Topic: [tpmdd-devel] [PATCH] TPM: Retry SaveState command in suspend path Thread-Index: AQHOI2IV2QjzRpkQ5kWpgc++qInY+pirJHYw Date: Mon, 18 Mar 2013 08:56:12 +0000 Message-ID: <74A44E99E3274B4CB570415926B37D4413DE67@MUCSE501.eu.infineon.com> References: <1363557399-11822-1-git-send-email-dlaurie@chromium.org> In-Reply-To: <1363557399-11822-1-git-send-email-dlaurie@chromium.org> Accept-Language: de-DE, en-US Content-Language: de-DE X-MS-Has-Attach: X-MS-TNEF-Correlator: x-originating-ip: [172.23.8.248] Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 8BIT MIME-Version: 1.0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1149 Lines: 36 Hi > The TPM is too busy to respond to the command immediately, but the > command could be resubmitted at a later time. The TPM MAY return > TPM_RETRY for any command at any time. > It can take several seconds before the TPM will respond again. I measured a typical time between 3 and 4 seconds and the timeout is set at a safe 5 seconds. > I tested a variety of TPMs from Infineon, Nuvoton, Atmel, and STMicro but was only able to reproduce this with LPC and I2C TPMs from Infineon. Yes, our TPMs respond with TPM_RETRY if the time between two TPM_SaveState is too short to prevent wear leveling. If I remember correctly the internal timer is set to 5sec. As you've already said this is compliant with the TCG specification. Nevertheless, the patch looks good to me. Reviewed-by: Peter Huewe Acked-by: Peter Huewe Thanks, Peter -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/