Intel Titan Ridge does not disable AUX timers when it gets SET_CONFIG with SET_LTTPR_MODE set which makes DP tunneling to fail. For this reason disable LTTPR on Titan Ridge device side. Signed-off-by: Mika Westerberg <mika.westerberg@xxxxxxxxxxxxxxx> --- drivers/thunderbolt/tb_regs.h | 1 + drivers/thunderbolt/tunnel.c | 10 ++++++++++ 2 files changed, 11 insertions(+) diff --git a/drivers/thunderbolt/tb_regs.h b/drivers/thunderbolt/tb_regs.h index dc00cbd69d36..70795a2aa9bb 100644 --- a/drivers/thunderbolt/tb_regs.h +++ b/drivers/thunderbolt/tb_regs.h @@ -389,6 +389,7 @@ struct tb_regs_port_header { #define DP_COMMON_CAP_1_LANE 0x0 #define DP_COMMON_CAP_2_LANES 0x1 #define DP_COMMON_CAP_4_LANES 0x2 +#define DP_COMMON_CAP_LTTPR_NS BIT(27) #define DP_COMMON_CAP_DPRX_DONE BIT(31) /* PCIe adapter registers */ diff --git a/drivers/thunderbolt/tunnel.c b/drivers/thunderbolt/tunnel.c index a473cc7d9a8d..118742ec93ed 100644 --- a/drivers/thunderbolt/tunnel.c +++ b/drivers/thunderbolt/tunnel.c @@ -580,6 +580,16 @@ static int tb_dp_xchg_caps(struct tb_tunnel *tunnel) out_dp_cap = tb_dp_cap_set_lanes(out_dp_cap, new_lanes); } + /* + * Titan Ridge does not disable AUX timers when it gets + * SET_CONFIG with SET_LTTPR_MODE set. This causes problems with + * DP tunneling. + */ + if (tb_route(out->sw) && tb_switch_is_titan_ridge(out->sw)) { + out_dp_cap |= DP_COMMON_CAP_LTTPR_NS; + tb_port_dbg(out, "disabling LTTPR\n"); + } + return tb_port_write(in, &out_dp_cap, TB_CFG_PORT, in->cap_adap + DP_REMOTE_CAP, 1); } -- 2.34.1