diff options
Diffstat (limited to 'drivers/thunderbolt/switch.c')
-rw-r--r-- | drivers/thunderbolt/switch.c | 294 |
1 files changed, 252 insertions, 42 deletions
diff --git a/drivers/thunderbolt/switch.c b/drivers/thunderbolt/switch.c index 9bd13ea87c9c..e09ac36f71a7 100644 --- a/drivers/thunderbolt/switch.c +++ b/drivers/thunderbolt/switch.c @@ -941,6 +941,22 @@ int tb_port_get_link_generation(struct tb_port *port) } } +static const char *width_name(enum tb_link_width width) +{ + switch (width) { + case TB_LINK_WIDTH_SINGLE: + return "symmetric, single lane"; + case TB_LINK_WIDTH_DUAL: + return "symmetric, dual lanes"; + case TB_LINK_WIDTH_ASYM_TX: + return "asymmetric, 3 transmitters, 1 receiver"; + case TB_LINK_WIDTH_ASYM_RX: + return "asymmetric, 3 receivers, 1 transmitter"; + default: + return "unknown"; + } +} + /** * tb_port_get_link_width() - Get current link width * @port: Port to check (USB4 or CIO) @@ -966,8 +982,15 @@ int tb_port_get_link_width(struct tb_port *port) LANE_ADP_CS_1_CURRENT_WIDTH_SHIFT; } -static bool tb_port_is_width_supported(struct tb_port *port, - unsigned int width_mask) +/** + * tb_port_width_supported() - Is the given link width supported + * @port: Port to check + * @width: Widths to check (bitmask) + * + * Can be called to any lane adapter. Checks if given @width is + * supported by the hardware and returns %true if it is. + */ +bool tb_port_width_supported(struct tb_port *port, unsigned int width) { u32 phy, widths; int ret; @@ -975,15 +998,23 @@ static bool tb_port_is_width_supported(struct tb_port *port, if (!port->cap_phy) return false; + if (width & (TB_LINK_WIDTH_ASYM_TX | TB_LINK_WIDTH_ASYM_RX)) { + if (tb_port_get_link_generation(port) < 4 || + !usb4_port_asym_supported(port)) + return false; + } + ret = tb_port_read(port, &phy, TB_CFG_PORT, port->cap_phy + LANE_ADP_CS_0, 1); if (ret) return false; - widths = (phy & LANE_ADP_CS_0_SUPPORTED_WIDTH_MASK) >> - LANE_ADP_CS_0_SUPPORTED_WIDTH_SHIFT; - - return widths & width_mask; + /* + * The field encoding is the same as &enum tb_link_width (which is + * passed to @width). + */ + widths = FIELD_GET(LANE_ADP_CS_0_SUPPORTED_WIDTH_MASK, phy); + return widths & width; } /** @@ -1018,10 +1049,18 @@ int tb_port_set_link_width(struct tb_port *port, enum tb_link_width width) val |= LANE_ADP_CS_1_TARGET_WIDTH_SINGLE << LANE_ADP_CS_1_TARGET_WIDTH_SHIFT; break; + case TB_LINK_WIDTH_DUAL: + if (tb_port_get_link_generation(port) >= 4) + return usb4_port_asym_set_link_width(port, width); val |= LANE_ADP_CS_1_TARGET_WIDTH_DUAL << LANE_ADP_CS_1_TARGET_WIDTH_SHIFT; break; + + case TB_LINK_WIDTH_ASYM_TX: + case TB_LINK_WIDTH_ASYM_RX: + return usb4_port_asym_set_link_width(port, width); + default: return -EINVAL; } @@ -1146,7 +1185,7 @@ void tb_port_lane_bonding_disable(struct tb_port *port) /** * tb_port_wait_for_link_width() - Wait until link reaches specific width * @port: Port to wait for - * @width_mask: Expected link width mask + * @width: Expected link width (bitmask) * @timeout_msec: Timeout in ms how long to wait * * Should be used after both ends of the link have been bonded (or @@ -1155,14 +1194,14 @@ void tb_port_lane_bonding_disable(struct tb_port *port) * within the given timeout, %0 if it did. Can be passed a mask of * expected widths and succeeds if any of the widths is reached. */ -int tb_port_wait_for_link_width(struct tb_port *port, unsigned int width_mask, +int tb_port_wait_for_link_width(struct tb_port *port, unsigned int width, int timeout_msec) { ktime_t timeout = ktime_add_ms(ktime_get(), timeout_msec); int ret; /* Gen 4 link does not support single lane */ - if ((width_mask & TB_LINK_WIDTH_SINGLE) && + if ((width & TB_LINK_WIDTH_SINGLE) && tb_port_get_link_generation(port) >= 4) return -EOPNOTSUPP; @@ -1176,7 +1215,7 @@ int tb_port_wait_for_link_width(struct tb_port *port, unsigned int width_mask, */ if (ret != -EACCES) return ret; - } else if (ret & width_mask) { + } else if (ret & width) { return 0; } @@ -2720,6 +2759,38 @@ static int tb_switch_update_link_attributes(struct tb_switch *sw) return 0; } +/* Must be called after tb_switch_update_link_attributes() */ +static void tb_switch_link_init(struct tb_switch *sw) +{ + struct tb_port *up, *down; + bool bonded; + + if (!tb_route(sw) || tb_switch_is_icm(sw)) + return; + + tb_sw_dbg(sw, "current link speed %u.0 Gb/s\n", sw->link_speed); + tb_sw_dbg(sw, "current link width %s\n", width_name(sw->link_width)); + + bonded = sw->link_width >= TB_LINK_WIDTH_DUAL; + + /* + * Gen 4 links come up as bonded so update the port structures + * accordingly. + */ + up = tb_upstream_port(sw); + down = tb_switch_downstream_port(sw); + + up->bonded = bonded; + if (up->dual_link_port) + up->dual_link_port->bonded = bonded; + tb_port_update_credits(up); + + down->bonded = bonded; + if (down->dual_link_port) + down->dual_link_port->bonded = bonded; + tb_port_update_credits(down); +} + /** * tb_switch_lane_bonding_enable() - Enable lane bonding * @sw: Switch to enable lane bonding @@ -2728,24 +2799,20 @@ static int tb_switch_update_link_attributes(struct tb_switch *sw) * switch. If conditions are correct and both switches support the feature, * lanes are bonded. It is safe to call this to any switch. */ -int tb_switch_lane_bonding_enable(struct tb_switch *sw) +static int tb_switch_lane_bonding_enable(struct tb_switch *sw) { struct tb_port *up, *down; - u64 route = tb_route(sw); - unsigned int width_mask; + unsigned int width; int ret; - if (!route) - return 0; - if (!tb_switch_lane_bonding_possible(sw)) return 0; up = tb_upstream_port(sw); down = tb_switch_downstream_port(sw); - if (!tb_port_is_width_supported(up, TB_LINK_WIDTH_DUAL) || - !tb_port_is_width_supported(down, TB_LINK_WIDTH_DUAL)) + if (!tb_port_width_supported(up, TB_LINK_WIDTH_DUAL) || + !tb_port_width_supported(down, TB_LINK_WIDTH_DUAL)) return 0; ret = tb_port_lane_bonding_enable(up); @@ -2762,21 +2829,10 @@ int tb_switch_lane_bonding_enable(struct tb_switch *sw) } /* Any of the widths are all bonded */ - width_mask = TB_LINK_WIDTH_DUAL | TB_LINK_WIDTH_ASYM_TX | - TB_LINK_WIDTH_ASYM_RX; + width = TB_LINK_WIDTH_DUAL | TB_LINK_WIDTH_ASYM_TX | + TB_LINK_WIDTH_ASYM_RX; - ret = tb_port_wait_for_link_width(down, width_mask, 100); - if (ret) { - tb_port_warn(down, "timeout enabling lane bonding\n"); - return ret; - } - - tb_port_update_credits(down); - tb_port_update_credits(up); - tb_switch_update_link_attributes(sw); - - tb_sw_dbg(sw, "lane bonding enabled\n"); - return ret; + return tb_port_wait_for_link_width(down, width, 100); } /** @@ -2786,20 +2842,27 @@ int tb_switch_lane_bonding_enable(struct tb_switch *sw) * Disables lane bonding between @sw and parent. This can be called even * if lanes were not bonded originally. */ -void tb_switch_lane_bonding_disable(struct tb_switch *sw) +static int tb_switch_lane_bonding_disable(struct tb_switch *sw) { struct tb_port *up, *down; int ret; - if (!tb_route(sw)) - return; - up = tb_upstream_port(sw); if (!up->bonded) - return; + return 0; - down = tb_switch_downstream_port(sw); + /* + * If the link is Gen 4 there is no way to switch the link to + * two single lane links so avoid that here. Also don't bother + * if the link is not up anymore (sw is unplugged). + */ + ret = tb_port_get_link_generation(up); + if (ret < 0) + return ret; + if (ret >= 4) + return -EOPNOTSUPP; + down = tb_switch_downstream_port(sw); tb_port_lane_bonding_disable(up); tb_port_lane_bonding_disable(down); @@ -2807,15 +2870,160 @@ void tb_switch_lane_bonding_disable(struct tb_switch *sw) * It is fine if we get other errors as the router might have * been unplugged. */ - ret = tb_port_wait_for_link_width(down, TB_LINK_WIDTH_SINGLE, 100); - if (ret == -ETIMEDOUT) - tb_sw_warn(sw, "timeout disabling lane bonding\n"); + return tb_port_wait_for_link_width(down, TB_LINK_WIDTH_SINGLE, 100); +} + +static int tb_switch_asym_enable(struct tb_switch *sw, enum tb_link_width width) +{ + struct tb_port *up, *down, *port; + enum tb_link_width down_width; + int ret; + + up = tb_upstream_port(sw); + down = tb_switch_downstream_port(sw); + + if (width == TB_LINK_WIDTH_ASYM_TX) { + down_width = TB_LINK_WIDTH_ASYM_RX; + port = down; + } else { + down_width = TB_LINK_WIDTH_ASYM_TX; + port = up; + } + + ret = tb_port_set_link_width(up, width); + if (ret) + return ret; + + ret = tb_port_set_link_width(down, down_width); + if (ret) + return ret; + + /* + * Initiate the change in the router that one of its TX lanes is + * changing to RX but do so only if there is an actual change. + */ + if (sw->link_width != width) { + ret = usb4_port_asym_start(port); + if (ret) + return ret; + + ret = tb_port_wait_for_link_width(up, width, 100); + if (ret) + return ret; + } + + sw->link_width = width; + return 0; +} + +static int tb_switch_asym_disable(struct tb_switch *sw) +{ + struct tb_port *up, *down; + int ret; + + up = tb_upstream_port(sw); + down = tb_switch_downstream_port(sw); + + ret = tb_port_set_link_width(up, TB_LINK_WIDTH_DUAL); + if (ret) + return ret; + + ret = tb_port_set_link_width(down, TB_LINK_WIDTH_DUAL); + if (ret) + return ret; + + /* + * Initiate the change in the router that has three TX lanes and + * is changing one of its TX lanes to RX but only if there is a + * change in the link width. + */ + if (sw->link_width > TB_LINK_WIDTH_DUAL) { + if (sw->link_width == TB_LINK_WIDTH_ASYM_TX) + ret = usb4_port_asym_start(up); + else + ret = usb4_port_asym_start(down); + if (ret) + return ret; + + ret = tb_port_wait_for_link_width(up, TB_LINK_WIDTH_DUAL, 100); + if (ret) + return ret; + } + + sw->link_width = TB_LINK_WIDTH_DUAL; + return 0; +} + +/** + * tb_switch_set_link_width() - Configure router link width + * @sw: Router to configure + * @width: The new link width + * + * Set device router link width to @width from router upstream port + * perspective. Supports also asymmetric links if the routers boths side + * of the link supports it. + * + * Does nothing for host router. + * + * Returns %0 in case of success, negative errno otherwise. + */ +int tb_switch_set_link_width(struct tb_switch *sw, enum tb_link_width width) +{ + struct tb_port *up, *down; + int ret = 0; + + if (!tb_route(sw)) + return 0; + + up = tb_upstream_port(sw); + down = tb_switch_downstream_port(sw); + + switch (width) { + case TB_LINK_WIDTH_SINGLE: + ret = tb_switch_lane_bonding_disable(sw); + break; + + case TB_LINK_WIDTH_DUAL: + if (sw->link_width == TB_LINK_WIDTH_ASYM_TX || + sw->link_width == TB_LINK_WIDTH_ASYM_RX) { + ret = tb_switch_asym_disable(sw); + if (ret) + break; + } + ret = tb_switch_lane_bonding_enable(sw); + break; + + case TB_LINK_WIDTH_ASYM_TX: + case TB_LINK_WIDTH_ASYM_RX: + ret = tb_switch_asym_enable(sw, width); + break; + } + + switch (ret) { + case 0: + break; + + case -ETIMEDOUT: + tb_sw_warn(sw, "timeout changing link width\n"); + return ret; + + case -ENOTCONN: + case -EOPNOTSUPP: + case -ENODEV: + return ret; + + default: + tb_sw_dbg(sw, "failed to change link width: %d\n", ret); + return ret; + } tb_port_update_credits(down); tb_port_update_credits(up); + tb_switch_update_link_attributes(sw); - tb_sw_dbg(sw, "lane bonding disabled\n"); + tb_sw_dbg(sw, "link width set to %s\n", width_name(width)); + return ret; } /** @@ -2975,6 +3183,8 @@ int tb_switch_add(struct tb_switch *sw) if (ret) return ret; + tb_switch_link_init(sw); + ret = tb_switch_clx_init(sw); if (ret) return ret; |