From patchwork Mon Sep 12 13:04:18 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Winkler, Tomas" X-Patchwork-Id: 9326459 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id BA3006048B for ; Mon, 12 Sep 2016 13:06:43 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id AB10F285B8 for ; Mon, 12 Sep 2016 13:06:43 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id A01F128DB3; Mon, 12 Sep 2016 13:06:43 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.9 required=2.0 tests=BAYES_00,RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from lists.sourceforge.net (lists.sourceforge.net [216.34.181.88]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id B17D428D9F for ; Mon, 12 Sep 2016 13:06:37 +0000 (UTC) Received: from localhost ([127.0.0.1] helo=sfs-ml-3.v29.ch3.sourceforge.com) by sfs-ml-3.v29.ch3.sourceforge.com with esmtp (Exim 4.76) (envelope-from ) id 1bjQwV-0006am-4N; Mon, 12 Sep 2016 13:06:35 +0000 Received: from sog-mx-2.v43.ch3.sourceforge.com ([172.29.43.192] helo=mx.sourceforge.net) by sfs-ml-3.v29.ch3.sourceforge.com with esmtp (Exim 4.76) (envelope-from ) id 1bjQwT-0006af-WE for tpmdd-devel@lists.sourceforge.net; Mon, 12 Sep 2016 13:06:34 +0000 Received-SPF: pass (sog-mx-2.v43.ch3.sourceforge.com: domain of intel.com designates 134.134.136.65 as permitted sender) client-ip=134.134.136.65; envelope-from=tomas.winkler@intel.com; helo=mga03.intel.com; Received: from mga03.intel.com ([134.134.136.65]) by sog-mx-2.v43.ch3.sourceforge.com with esmtps (TLSv1:AES256-SHA:256) (Exim 4.76) id 1bjQwQ-00017a-Hq for tpmdd-devel@lists.sourceforge.net; Mon, 12 Sep 2016 13:06:33 +0000 Received: from fmsmga005.fm.intel.com ([10.253.24.32]) by orsmga103.jf.intel.com with ESMTP; 12 Sep 2016 06:06:25 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.30,322,1470726000"; d="scan'208";a="7328830" Received: from twinkler-lnx.jer.intel.com ([10.12.87.167]) by fmsmga005.fm.intel.com with ESMTP; 12 Sep 2016 06:06:23 -0700 From: Tomas Winkler To: tpmdd-devel@lists.sourceforge.net, Jason Gunthorpe , Jarkko Sakkinen Date: Mon, 12 Sep 2016 16:04:18 +0300 Message-Id: <1473685461-6540-2-git-send-email-tomas.winkler@intel.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1473685461-6540-1-git-send-email-tomas.winkler@intel.com> References: <1473685461-6540-1-git-send-email-tomas.winkler@intel.com> X-Headers-End: 1bjQwQ-00017a-Hq Cc: linux-kernel@vger.kernel.org Subject: [tpmdd-devel] [PATCH v3 1/4] tpm/tpm_crb: implement tpm crb idle state X-BeenThere: tpmdd-devel@lists.sourceforge.net X-Mailman-Version: 2.1.9 Precedence: list List-Id: Tpm Device Driver maintainance List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Errors-To: tpmdd-devel-bounces@lists.sourceforge.net X-Virus-Scanned: ClamAV using ClamSMTP The register TPM_CRB_CTRL_REQ_x contains bits goIdle and cmdReady for SW to indicate that the device can enter or should exit the idle state. The legacy ACPI-start (SMI + DMA) based devices do not support these bits and the idle state management is not exposed to the host SW. Thus, this functionality only is enabled only for a CRB start (MMIO) based devices. Based on Jarkko Sakkinen oringal patch: 'tpm_crb: implement power tpm crb power management' Signed-off-by: Tomas Winkler Tested-by: Jarkko Sakkinen --- V2: do not export the functions via tpm ops V3: fix lower case corruption; adjust function documentation drivers/char/tpm/tpm_crb.c | 69 ++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 69 insertions(+) diff --git a/drivers/char/tpm/tpm_crb.c b/drivers/char/tpm/tpm_crb.c index 6e9d1bca712f..b6923a8b3ff7 100644 --- a/drivers/char/tpm/tpm_crb.c +++ b/drivers/char/tpm/tpm_crb.c @@ -83,6 +83,75 @@ struct crb_priv { u32 cmd_size; }; +/** + * crb_go_idle - request tpm crb device to go the idle state + * + * @dev: crb device + * @priv: crb private data + * + * Write CRB_CTRL_REQ_GO_IDLE to TPM_CRB_CTRL_REQ + * The device should respond within TIMEOUT_C by clearing the bit. + * Anyhow, we do not wait here as a consequent CMD_READY request + * will be handled correctly even if idle was not completed. + * + * The function does nothing for devices with ACPI-start method. + * + * Return: 0 always + */ +static int __maybe_unused crb_go_idle(struct device *dev, struct crb_priv *priv) +{ + if (priv->flags & CRB_FL_ACPI_START) + return 0; + + iowrite32(CRB_CTRL_REQ_GO_IDLE, &priv->cca->req); + /* we don't really care when this settles */ + + return 0; +} + +/** + * crb_cmd_ready - request tpm crb device to enter ready state + * + * @dev: crb device + * @priv: crb private data + * + * Write CRB_CTRL_REQ_CMD_READY to TPM_CRB_CTRL_REQ + * and poll till the device acknowledge it by clearing the bit. + * The device should respond within TIMEOUT_C. + * + * The function does nothing for devices with ACPI-start method + * + * Return: 0 on success -ETIME on timeout; + */ +static int __maybe_unused crb_cmd_ready(struct device *dev, + struct crb_priv *priv) +{ + ktime_t stop, start; + + if (priv->flags & CRB_FL_ACPI_START) + return 0; + + iowrite32(CRB_CTRL_REQ_CMD_READY, &priv->cca->req); + + start = ktime_get(); + stop = ktime_add(start, ms_to_ktime(TPM2_TIMEOUT_C)); + do { + if (!(ioread32(&priv->cca->req) & CRB_CTRL_REQ_CMD_READY)) { + dev_dbg(dev, "cmdReady in %lld usecs\n", + ktime_to_us(ktime_sub(ktime_get(), start))); + return 0; + } + usleep_range(50, 100); + } while (ktime_before(ktime_get(), stop)); + + if (ioread32(&priv->cca->req) & CRB_CTRL_REQ_CMD_READY) { + dev_warn(dev, "cmdReady timed out\n"); + return -ETIME; + } + + return 0; +} + static SIMPLE_DEV_PM_OPS(crb_pm, tpm_pm_suspend, tpm_pm_resume); static u8 crb_status(struct tpm_chip *chip)