On 3/6/24 6:20 PM, Alexey Kardashevskiy wrote:
> PCIe r6.1, sec 6.30.1.1 defines a "DOE Discovery Version" field in
> the DOE Discovery Request Data Object Contents (3rd DW) as:
>
> 15:8 DOE Discovery Version – must be 02h if the Capability Version in
> the Data Object Exchange Extended Capability is 02h or greater.
Does this change fix any functional issue? If yes, please add Fixes:
tag and probably CC stable?
>
> Add support for the version on devices with the DOE v2 capability.
>
> Signed-off-by: Alexey Kardashevskiy <aik@xxxxxxx>
> ---
Change wise looks fine to me.
Reviewed-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@xxxxxxxxxxxxxxx>
> Changes:
> v3:
> * updated subject line
> * dropped "DISCOVER_" from the new field macro
>
> v2:
> * added the section number to the commit log
> ---
> include/uapi/linux/pci_regs.h | 1 +
> drivers/pci/doe.c | 11 ++++++++---
> 2 files changed, 9 insertions(+), 3 deletions(-)
>
> diff --git a/include/uapi/linux/pci_regs.h b/include/uapi/linux/pci_regs.h
> index a39193213ff2..fbca743b2b86 100644
> --- a/include/uapi/linux/pci_regs.h
> +++ b/include/uapi/linux/pci_regs.h
> @@ -1144,6 +1144,7 @@
> #define PCI_DOE_DATA_OBJECT_HEADER_2_LENGTH 0x0003ffff
>
> #define PCI_DOE_DATA_OBJECT_DISC_REQ_3_INDEX 0x000000ff
> +#define PCI_DOE_DATA_OBJECT_DISC_REQ_3_VER 0x0000ff00
> #define PCI_DOE_DATA_OBJECT_DISC_RSP_3_VID 0x0000ffff
> #define PCI_DOE_DATA_OBJECT_DISC_RSP_3_PROTOCOL 0x00ff0000
> #define PCI_DOE_DATA_OBJECT_DISC_RSP_3_NEXT_INDEX 0xff000000
> diff --git a/drivers/pci/doe.c b/drivers/pci/doe.c
> index 61f0531d2b1d..c94c2b0767f3 100644
> --- a/drivers/pci/doe.c
> +++ b/drivers/pci/doe.c
> @@ -381,11 +381,13 @@ static void pci_doe_task_complete(struct pci_doe_task *task)
> complete(task->private);
> }
>
> -static int pci_doe_discovery(struct pci_doe_mb *doe_mb, u8 *index, u16 *vid,
> +static int pci_doe_discovery(struct pci_doe_mb *doe_mb, u8 capver, u8 *index, u16 *vid,
> u8 *protocol)
> {
> u32 request_pl = FIELD_PREP(PCI_DOE_DATA_OBJECT_DISC_REQ_3_INDEX,
> - *index);
> + *index) |
> + FIELD_PREP(PCI_DOE_DATA_OBJECT_DISC_REQ_3_VER,
> + (capver >= 2) ? 2 : 0);
> __le32 request_pl_le = cpu_to_le32(request_pl);
> __le32 response_pl_le;
> u32 response_pl;
> @@ -419,13 +421,16 @@ static int pci_doe_cache_protocols(struct pci_doe_mb *doe_mb)
> {
> u8 index = 0;
> u8 xa_idx = 0;
> + u32 hdr = 0;
> +
> + pci_read_config_dword(doe_mb->pdev, doe_mb->cap_offset, &hdr);
>
> do {
> int rc;
> u16 vid;
> u8 prot;
>
> - rc = pci_doe_discovery(doe_mb, &index, &vid, &prot);
> + rc = pci_doe_discovery(doe_mb, PCI_EXT_CAP_VER(hdr), &index, &vid, &prot);
> if (rc)
> return rc;
>
--
Sathyanarayanan Kuppuswamy
Linux Kernel Developer
