From e879a709de0210802ba14243a168d632cb7ab527 Mon Sep 17 00:00:00 2001 From: Mika Westerberg Date: Thu, 11 Oct 2018 12:33:08 +0300 Subject: [PATCH] thunderbolt: Configure lanes when switch is initialized Thunderbolt 2 devices and beyond need to have additional bits set in link controller specific registers. This includes two bits in LC_SX_CTRL that tell the link controller which lane is connected and whether it is upstream facing or not. Signed-off-by: Mika Westerberg --- drivers/thunderbolt/lc.c | 114 ++++++++++++++++++++++++++++++++++ drivers/thunderbolt/switch.c | 9 +++ drivers/thunderbolt/tb.h | 2 + drivers/thunderbolt/tb_regs.h | 11 ++++ 4 files changed, 136 insertions(+) diff --git a/drivers/thunderbolt/lc.c b/drivers/thunderbolt/lc.c index 2134a55ed837..a5dddf176546 100644 --- a/drivers/thunderbolt/lc.c +++ b/drivers/thunderbolt/lc.c @@ -19,3 +19,117 @@ int tb_lc_read_uuid(struct tb_switch *sw, u32 *uuid) return -EINVAL; return tb_sw_read(sw, uuid, TB_CFG_SWITCH, sw->cap_lc + TB_LC_FUSE, 4); } + +static int read_lc_desc(struct tb_switch *sw, u32 *desc) +{ + if (!sw->cap_lc) + return -EINVAL; + return tb_sw_read(sw, desc, TB_CFG_SWITCH, sw->cap_lc + TB_LC_DESC, 1); +} + +static int find_port_lc_cap(struct tb_port *port) +{ + struct tb_switch *sw = port->sw; + int start, phys, ret, size; + u32 desc; + + ret = read_lc_desc(sw, &desc); + if (ret) + return ret; + + /* Start of port LC registers */ + start = (desc & TB_LC_DESC_SIZE_MASK) >> TB_LC_DESC_SIZE_SHIFT; + size = (desc & TB_LC_DESC_PORT_SIZE_MASK) >> TB_LC_DESC_PORT_SIZE_SHIFT; + phys = tb_phy_port_from_link(port->port); + + return sw->cap_lc + start + phys * size; +} + +static int tb_lc_configure_lane(struct tb_port *port, bool configure) +{ + bool upstream = tb_is_upstream_port(port); + struct tb_switch *sw = port->sw; + u32 ctrl, lane; + int cap, ret; + + if (sw->generation < 2) + return 0; + + cap = find_port_lc_cap(port); + if (cap < 0) + return cap; + + ret = tb_sw_read(sw, &ctrl, TB_CFG_SWITCH, cap + TB_LC_SX_CTRL, 1); + if (ret) + return ret; + + /* Resolve correct lane */ + if (port->port % 2) + lane = TB_LC_SX_CTRL_L1C; + else + lane = TB_LC_SX_CTRL_L2C; + + if (configure) { + ctrl |= lane; + if (upstream) + ctrl |= TB_LC_SX_CTRL_UPSTREAM; + } else { + ctrl &= ~lane; + if (upstream) + ctrl &= ~TB_LC_SX_CTRL_UPSTREAM; + } + + return tb_sw_write(sw, &ctrl, TB_CFG_SWITCH, cap + TB_LC_SX_CTRL, 1); +} + +/** + * tb_lc_configure_link() - Let LC know about configured link + * @sw: Switch that is being added + * + * Informs LC of both parent switch and @sw that there is established + * link between the two. + */ +int tb_lc_configure_link(struct tb_switch *sw) +{ + struct tb_port *up, *down; + int ret; + + if (!sw->config.enabled || !tb_route(sw)) + return 0; + + up = tb_upstream_port(sw); + down = tb_port_at(tb_route(sw), tb_to_switch(sw->dev.parent)); + + /* Configure parent link toward this switch */ + ret = tb_lc_configure_lane(down, true); + if (ret) + return ret; + + /* Configure upstream link from this switch to the parent */ + ret = tb_lc_configure_lane(up, true); + if (ret) + tb_lc_configure_lane(down, false); + + return ret; +} + +/** + * tb_lc_unconfigure_link() - Let LC know about unconfigured link + * @sw: Switch to unconfigure + * + * Informs LC of both parent switch and @sw that the link between the + * two does not exist anymore. + */ +void tb_lc_unconfigure_link(struct tb_switch *sw) +{ + struct tb_port *up, *down; + + if (sw->is_unplugged || !sw->config.enabled || !tb_route(sw)) + return; + + up = tb_upstream_port(sw); + down = tb_port_at(tb_route(sw), tb_to_switch(sw->dev.parent)); + + tb_lc_configure_lane(up, false); + tb_lc_configure_lane(down, false); +} diff --git a/drivers/thunderbolt/switch.c b/drivers/thunderbolt/switch.c index 63ff4c753d89..dd218dc4781b 100644 --- a/drivers/thunderbolt/switch.c +++ b/drivers/thunderbolt/switch.c @@ -1276,6 +1276,10 @@ int tb_switch_configure(struct tb_switch *sw) if (ret) return ret; + ret = tb_lc_configure_link(sw); + if (ret) + return ret; + return tb_plug_events_active(sw, true); } @@ -1486,6 +1490,7 @@ void tb_switch_remove(struct tb_switch *sw) if (!sw->is_unplugged) tb_plug_events_active(sw, false); + tb_lc_unconfigure_link(sw); tb_switch_nvm_remove(sw); @@ -1545,6 +1550,10 @@ int tb_switch_resume(struct tb_switch *sw) if (err) return err; + err = tb_lc_configure_link(sw); + if (err) + return err; + err = tb_plug_events_active(sw, true); if (err) return err; diff --git a/drivers/thunderbolt/tb.h b/drivers/thunderbolt/tb.h index e52d39b25266..69e0534224d8 100644 --- a/drivers/thunderbolt/tb.h +++ b/drivers/thunderbolt/tb.h @@ -465,6 +465,8 @@ int tb_drom_read(struct tb_switch *sw); int tb_drom_read_uid_only(struct tb_switch *sw, u64 *uid); int tb_lc_read_uuid(struct tb_switch *sw, u32 *uuid); +int tb_lc_configure_link(struct tb_switch *sw); +void tb_lc_unconfigure_link(struct tb_switch *sw); static inline int tb_route_length(u64 route) { diff --git a/drivers/thunderbolt/tb_regs.h b/drivers/thunderbolt/tb_regs.h index 4895ae9f0b40..e0f867dad5cf 100644 --- a/drivers/thunderbolt/tb_regs.h +++ b/drivers/thunderbolt/tb_regs.h @@ -238,6 +238,17 @@ struct tb_regs_hop { } __packed; /* Common link controller registers */ +#define TB_LC_DESC 0x02 +#define TB_LC_DESC_SIZE_SHIFT 8 +#define TB_LC_DESC_SIZE_MASK GENMASK(15, 8) +#define TB_LC_DESC_PORT_SIZE_SHIFT 16 +#define TB_LC_DESC_PORT_SIZE_MASK GENMASK(27, 16) #define TB_LC_FUSE 0x03 +/* Link controller registers */ +#define TB_LC_SX_CTRL 0x96 +#define TB_LC_SX_CTRL_L1C BIT(16) +#define TB_LC_SX_CTRL_L2C BIT(20) +#define TB_LC_SX_CTRL_UPSTREAM BIT(30) + #endif -- 2.30.2