From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jarkko Sakkinen Subject: Re: [PATCH 3/3] tpm/tpm_crb: cache cmd_size register value. Date: Thu, 8 Sep 2016 14:00:34 +0300 Message-ID: <20160908110034.GC4712@intel.com> References: <1473247953-24617-1-git-send-email-tomas.winkler@intel.com> <1473247953-24617-4-git-send-email-tomas.winkler@intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Content-Disposition: inline In-Reply-To: <1473247953-24617-4-git-send-email-tomas.winkler-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: tpmdd-devel-bounces-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org To: Tomas Winkler Cc: tpmdd-devel-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org List-Id: tpmdd-devel@lists.sourceforge.net On Wed, Sep 07, 2016 at 02:32:33PM +0300, Tomas Winkler wrote: > Instead of expensive register access on retrieving cmd_size > on each send, save the value during initialization in the private > context. The value doesn't change. > > Signed-off-by: Tomas Winkler Reviewed-by: Jarkko Sakkinen /Jarkko > --- > drivers/char/tpm/tpm_crb.c | 10 +++++----- > 1 file changed, 5 insertions(+), 5 deletions(-) > > diff --git a/drivers/char/tpm/tpm_crb.c b/drivers/char/tpm/tpm_crb.c > index cf9aab698dfe..f8c9d587029b 100644 > --- a/drivers/char/tpm/tpm_crb.c > +++ b/drivers/char/tpm/tpm_crb.c > @@ -81,6 +81,7 @@ struct crb_priv { > struct crb_control_area __iomem *cca; > u8 __iomem *cmd; > u8 __iomem *rsp; > + u32 cmd_size; > }; > > /** > @@ -217,11 +218,9 @@ static int crb_send(struct tpm_chip *chip, u8 *buf, size_t len) > struct crb_priv *priv = dev_get_drvdata(&chip->dev); > int rc = 0; > > - if (len > ioread32(&priv->cca->cmd_size)) { > - dev_err(&chip->dev, > - "invalid command count value %x %zx\n", > - (unsigned int) len, > - (size_t) ioread32(&priv->cca->cmd_size)); > + if (len > priv->cmd_size) { > + dev_err(&chip->dev, "invalid command count value %zd %d\n", > + len, priv->cmd_size); > return -E2BIG; > } > > @@ -374,6 +373,7 @@ static int crb_map_io(struct acpi_device *device, struct crb_priv *priv, > ret = PTR_ERR(priv->cmd); > goto out; > } > + priv->cmd_size = cmd_size; > > memcpy_fromio(&rsp_pa, &priv->cca->rsp_pa, 8); > rsp_pa = le64_to_cpu(rsp_pa); > -- > 2.7.4 > ------------------------------------------------------------------------------