2021-06-18 02:38:21

by David E. Box

Subject: [PATCH 1/4] PCI: Add #defines for accessing PCIE DVSEC fields

Add #defines for accessing Vendor ID, Revision, Length, and ID offsets
in the Designated Vendor Specific Extended Capability (DVSEC). Defined
in PCIe r5.0, sec 7.9.6.

Signed-off-by: David E. Box <[email protected]>
---
include/uapi/linux/pci_regs.h | 4 ++++
1 file changed, 4 insertions(+)

diff --git a/include/uapi/linux/pci_regs.h b/include/uapi/linux/pci_regs.h
index e709ae8235e7..57ee51f19283 100644
--- a/include/uapi/linux/pci_regs.h
+++ b/include/uapi/linux/pci_regs.h
@@ -1080,7 +1080,11 @@

/* Designated Vendor-Specific (DVSEC, PCI_EXT_CAP_ID_DVSEC) */
#define PCI_DVSEC_HEADER1 0x4 /* Designated Vendor-Specific Header1 */
+#define PCI_DVSEC_HEADER1_VID(x) ((x) & 0xffff)
+#define PCI_DVSEC_HEADER1_REV(x) (((x) >> 16) & 0xf)
+#define PCI_DVSEC_HEADER1_LEN(x) (((x) >> 20) & 0xfff)
#define PCI_DVSEC_HEADER2 0x8 /* Designated Vendor-Specific Header2 */
+#define PCI_DVSEC_HEADER2_ID(x) ((x) & 0xffff)

/* Data Link Feature */
#define PCI_DLF_CAP 0x04 /* Capabilities Register */
--
2.25.1

2021-06-22 15:06:15

by Bjorn Helgaas

Subject: Re: [PATCH 1/4] PCI: Add #defines for accessing PCIE DVSEC fields

[+cc Dan, Jonathan]

On Thu, Jun 17, 2021 at 02:54:05PM -0700, David E. Box wrote:
> Add #defines for accessing Vendor ID, Revision, Length, and ID offsets
> in the Designated Vendor Specific Extended Capability (DVSEC). Defined
> in PCIe r5.0, sec 7.9.6.
>
> Signed-off-by: David E. Box <[email protected]>

Acked-by: Bjorn Helgaas <[email protected]>

I don't have time right now to really look at the
intel_extended_caps.c patch [1], but I wonder if there's anything
there that could be abstracted and shared with CXL, etc? If not, no
worries.

[1] https://lore.kernel.org/r/[email protected]

> ---
> include/uapi/linux/pci_regs.h | 4 ++++
> 1 file changed, 4 insertions(+)
>
> diff --git a/include/uapi/linux/pci_regs.h b/include/uapi/linux/pci_regs.h
> index e709ae8235e7..57ee51f19283 100644
> --- a/include/uapi/linux/pci_regs.h
> +++ b/include/uapi/linux/pci_regs.h
> @@ -1080,7 +1080,11 @@
>
> /* Designated Vendor-Specific (DVSEC, PCI_EXT_CAP_ID_DVSEC) */
> #define PCI_DVSEC_HEADER1 0x4 /* Designated Vendor-Specific Header1 */
> +#define PCI_DVSEC_HEADER1_VID(x) ((x) & 0xffff)
> +#define PCI_DVSEC_HEADER1_REV(x) (((x) >> 16) & 0xf)
> +#define PCI_DVSEC_HEADER1_LEN(x) (((x) >> 20) & 0xfff)
> #define PCI_DVSEC_HEADER2 0x8 /* Designated Vendor-Specific Header2 */
> +#define PCI_DVSEC_HEADER2_ID(x) ((x) & 0xffff)
>
> /* Data Link Feature */
> #define PCI_DLF_CAP 0x04 /* Capabilities Register */
> --
> 2.25.1
>