Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753390AbcLFSlj (ORCPT ); Tue, 6 Dec 2016 13:41:39 -0500 Received: from mga11.intel.com ([192.55.52.93]:13971 "EHLO mga11.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751845AbcLFSlg (ORCPT ); Tue, 6 Dec 2016 13:41:36 -0500 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.33,310,1477983600"; d="scan'208";a="39662052" Date: Tue, 6 Dec 2016 20:41:16 +0200 From: Jarkko Sakkinen To: "Winkler, Tomas" Cc: Peter Huewe , "linux-security-module@vger.kernel.org" , "moderated list:TPM DEVICE DRIVER" , open list Subject: Re: [tpmdd-devel] [PATCH v2 3/3] tpm_crb: request and relinquish locality 0 Message-ID: <20161206184116.dprqkia5bjpcpwim@intel.com> References: <20161203175213.10210-1-jarkko.sakkinen@linux.intel.com> <20161203175213.10210-4-jarkko.sakkinen@linux.intel.com> <20161203184207.5vjrxqowfodni73m@intel.com> <5B8DA87D05A7694D9FA63FD143655C1B54337027@hasmsx108.ger.corp.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <5B8DA87D05A7694D9FA63FD143655C1B54337027@hasmsx108.ger.corp.intel.com> Organization: Intel Finland Oy - BIC 0357606-4 - Westendinkatu 7, 02160 Espoo User-Agent: Mutt/1.6.2-neo (2016-08-21) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 4146 Lines: 114 On Mon, Dec 05, 2016 at 09:51:42PM +0000, Winkler, Tomas wrote: > > > > CC linux-security-module > > > > On Sat, Dec 03, 2016 at 07:52:13PM +0200, Jarkko Sakkinen wrote: > > > Request and relinquish locality for the driver use in order to be a > > > better citizen in a multi locality environment like TXT. The locality > > > is requested and relinquished as part of going into and waking up from > > > idle. > > > This has nothing to do with power management, please note, that this is run via runtime_pm handlers, > which can be disabled via sysfs and actually on server platforms runtime pm is not relevant, > while you cannot disable locality acquire/relinquish flow. > > NACK Good point. I'll move it as part of tpm_transmit() /Jarkko > > > Signed-off-by: Jarkko Sakkinen > > > --- > > > drivers/char/tpm/tpm_crb.c | 36 ++++++++++++++++++++++++------------ > > > 1 file changed, 24 insertions(+), 12 deletions(-) > > > > > > diff --git a/drivers/char/tpm/tpm_crb.c b/drivers/char/tpm/tpm_crb.c > > > index f986d02..f6e0beb 100644 > > > --- a/drivers/char/tpm/tpm_crb.c > > > +++ b/drivers/char/tpm/tpm_crb.c > > > @@ -34,6 +34,15 @@ enum crb_defaults { > > > CRB_ACPI_START_INDEX = 1, > > > }; > > > > > > +enum crb_loc_ctrl { > > > + CRB_LOC_CTRL_REQUEST_ACCESS = BIT(0), > > > + CRB_LOC_CTRL_RELINQUISH = BIT(1), > > > +}; > > > + > > > +enum crb_loc_state { > > > + CRB_LOC_STATE_LOC_ASSIGNED = BIT(1), > > > +}; > > > + > > > enum crb_ctrl_req { > > > CRB_CTRL_REQ_CMD_READY = BIT(0), > > > CRB_CTRL_REQ_GO_IDLE = BIT(1), > > > @@ -101,12 +110,8 @@ struct crb_priv { > > > * @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. > > > + * Put device to the idle state and relinquish locality. The function > > > + does > > > + * nothing for devices with the ACPI-start method. > > > * > > > * Return: 0 always > > > */ > > > @@ -115,6 +120,7 @@ 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_LOC_CTRL_RELINQUISH, &priv->regs_h->loc_ctrl); > This is misleading this has nothing to do with go idle, what is the > > > iowrite32(CRB_CTRL_REQ_GO_IDLE, &priv->regs_t->ctrl_req); > > > /* we don't really care when this settles */ > > > > > > @@ -146,11 +152,8 @@ static bool crb_wait_for_reg_32(u32 __iomem *reg, > > u32 mask, u32 value, > > > * @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 > > > + * Try to wake up the device and request locality. The function does > > > + nothing > > > + * for devices with the ACPI-start method. > > > * > > > * Return: 0 on success -ETIME on timeout; > > > */ > > > @@ -165,7 +168,16 @@ static int __maybe_unused crb_cmd_ready(struct > > device *dev, > > > CRB_CTRL_REQ_CMD_READY /* mask */, > > > 0, /* value */ > > > TPM2_TIMEOUT_C)) { > > > - dev_warn(dev, "cmdReady timed out\n"); > > > + dev_warn(dev, "TPM_CRB_CTRL_REQ_x.cmdReady timed > > out\n"); > We are always in locality 0 here, right? > > > > + return -ETIME; > > > + } > > > + > > > + iowrite32(CRB_LOC_CTRL_REQUEST_ACCESS, &priv->regs_h- > > >loc_ctrl); > > > + if (!crb_wait_for_reg_32(&priv->regs_h->loc_state, > > > + CRB_LOC_STATE_LOC_ASSIGNED, /* mask */ > > > + CRB_LOC_STATE_LOC_ASSIGNED, /* value */ > > > + TPM2_TIMEOUT_C)) { > > > + dev_warn(dev, "TPM_LOC_STATE_x.requestAccess timed > > out\n"); > > > > > return -ETIME; > > > } > >