Re: [PATCH V2 2/9] PCI: Add TPH related register definition

From: Bjorn Helgaas
Date: Fri Jun 07 2024 - 12:42:26 EST


On Fri, May 31, 2024 at 04:38:34PM -0500, Wei Huang wrote:
> Linux has some basic, but incomplete, definition for the TPH Requester
> capability registers. Also the control registers of TPH Requester and
> the TPH Completer are missing. This patch adds all required definitions
> to support TPH enablement.

s/This patch adds/Add/

> +#define PCI_EXP_DEVCAP2_TPH_COMP_SHIFT 12
> +#define PCI_EXP_DEVCAP2_TPH_COMP_NONE 0x0 /* None */
> +#define PCI_EXP_DEVCAP2_TPH_COMP_TPH_ONLY 0x1 /* TPH only */
> +#define PCI_EXP_DEVCAP2_TPH_COMP_TPH_AND_EXT 0x3 /* TPH and Extended TPH */

Drop the _SHIFT definitions and use FIELD_GET() and FIELD_PREP()
instead.

> /* TPH Requester */
> #define PCI_TPH_CAP 4 /* capability register */
> +#define PCI_TPH_CAP_NO_ST 0x1 /* no ST mode supported */
> +#define PCI_TPH_CAP_NO_ST_SHIFT 0x0 /* no ST mode supported shift */

Drop _SHIFT and show full register width for PCI_TPH_CAP_NO_ST, e.g.,

#define PCI_TPH_CAP_NO_ST 0x00000001

The existing PCI_TPH_CAP_* definitions don't follow that convention,
but the rest of the file does, and this should match.