Re: [PATCH 1/3] tpm_crb: map locality registers

From: Jason Gunthorpe
Date: Tue Oct 11 2016 - 13:02:42 EST


On Tue, Oct 11, 2016 at 12:23:04PM +0300, Jarkko Sakkinen wrote:
> In order to provide access to locality registers, this commits adds
> mapping of the head of the CRB registers, which are located right
> before the control area.

I think you should squash this into the prior patch, no sense in
changing all these lines twice

But looks better to me.

> - priv->cca = crb_map_res(dev, priv, &io_res, buf->control_address,
> - sizeof(struct crb_control_area));
> - if (IS_ERR(priv->cca))
> - return PTR_ERR(priv->cca);
> + if (priv->flags & CRB_FL_CRB_START) {
> + priv->regs_h = crb_map_res(dev, priv, &io_res, io_res.start,
> + sizeof(struct crb_regs_head));
> + if (IS_ERR(priv->regs_h))
> + return PTR_ERR(priv->regs_h);
> + }
> +
> + priv->regs_t = crb_map_res(dev, priv, &io_res, buf->control_address,
> + sizeof(struct crb_regs_tail));
> + if (IS_ERR(priv->regs_t))
> + return PTR_ERR(priv->regs_t);

So.. The ACPI IO region starts at the head area and continues to
include the control area, as one nice sane region - except for some
older stuff that puts the control area outside the ACPI IO region?

That makes a lot more sense..

Maybe chuck in a

if (priv->flags & CRB_FL_CRB_START) {
if (buf->control_address != io_res.start + sizeof(struct
crb_regs_head))
dev_warn(dev, FIRMWARE_BUG "Bad ACPI memory layout")

Jason