From aa77ea0e43dc5bb0c1dcc9bad76afaa7faca8cab Mon Sep 17 00:00:00 2001 From: Tomas Winkler Date: Mon, 12 Sep 2016 13:52:10 +0300 Subject: [PATCH] tpm/tpm_crb: cache cmd_size register value. 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 Tested-by: Jarkko Sakkinen Signed-off-by: Jarkko Sakkinen --- 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 e76a8ee..18b5b83 100644 --- a/drivers/char/tpm/tpm_crb.c +++ b/drivers/char/tpm/tpm_crb.c @@ -80,6 +80,7 @@ struct crb_priv { struct crb_control_area __iomem *cca; u8 __iomem *cmd; u8 __iomem *rsp; + u32 cmd_size; }; static SIMPLE_DEV_PM_OPS(crb_pm, tpm_pm_suspend, tpm_pm_resume); @@ -146,11 +147,9 @@ static int crb_send(struct tpm_chip *chip, u8 *buf, size_t len) */ iowrite32(0, &priv->cca->cancel); - 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; } @@ -301,6 +300,7 @@ static int crb_map_io(struct acpi_device *device, struct crb_priv *priv, dev_err(dev, FW_BUG "overlapping command and response buffer sizes are not identical"); return -EINVAL; } + priv->cmd_size = cmd_size; priv->rsp = priv->cmd; return 0; -- 2.7.4