On Tue, Oct 01, 2019 at 02:38:20PM +0300, Mika Westerberg wrote:
> Titan Ridge devices and newer need an additional connection manager
> handshake in order to do proper Display Port tunneling so implement it
> here.
>
> Signed-off-by: Mika Westerberg <mika.westerberg@xxxxxxxxxxxxxxx>
> ---
> drivers/thunderbolt/tb_regs.h | 3 +++
> drivers/thunderbolt/tunnel.c | 44 +++++++++++++++++++++++++++++++++++
> 2 files changed, 47 insertions(+)
>
> diff --git a/drivers/thunderbolt/tb_regs.h b/drivers/thunderbolt/tb_regs.h
> index 3a39490a954b..8d11b4a2d552 100644
> --- a/drivers/thunderbolt/tb_regs.h
> +++ b/drivers/thunderbolt/tb_regs.h
> @@ -252,6 +252,9 @@ struct tb_regs_port_header {
> #define ADP_DP_CS_3_HDPC BIT(9)
> #define DP_LOCAL_CAP 0x04
> #define DP_REMOTE_CAP 0x05
> +#define DP_STATUS_CTRL 0x06
> +#define DP_STATUS_CTRL_CMHS BIT(25)
> +#define DP_STATUS_CTRL_UF BIT(26)
>
> /* PCIe adapter registers */
> #define ADP_PCIE_CS_0 0x00
> diff --git a/drivers/thunderbolt/tunnel.c b/drivers/thunderbolt/tunnel.c
> index 3353396e0806..369800110e5e 100644
> --- a/drivers/thunderbolt/tunnel.c
> +++ b/drivers/thunderbolt/tunnel.c
> @@ -6,6 +6,7 @@
> * Copyright (C) 2019, Intel Corporation
> */
>
> +#include <linux/delay.h>
> #include <linux/slab.h>
> #include <linux/list.h>
>
> @@ -242,6 +243,41 @@ struct tb_tunnel *tb_tunnel_alloc_pci(struct tb *tb, struct tb_port *up,
> return tunnel;
> }
>
> +static int tb_dp_cm_handshake(struct tb_port *in, struct tb_port *out)
> +{
> + int timeout = 10;
> + u32 val;
> + int ret;
> +
> + /* Both ends need to support this */
> + if (!tb_switch_is_tr(in->sw) || !tb_switch_is_tr(out->sw))
> + return 0;
So if the ends are both "Titan Ridge", matches your changelog text, but
where is the "and newer" comment being checked here?
thanks,
greg k-h
