From: Gil Fine <gil.fine@xxxxxxxxxxxxxxx> commit cd0c1e582b055dea615001b8bd8eccaf6f69f7ce upstream. According to USB4 retimer specification, the process of firmware update sequence requires issuing a SET_INBOUND_SBTX port operation that later shall be followed by UNSET_INBOUND_SBTX port operation. This last step is not currently issued by the driver but it is necessary to make sure the retimers are put back to passthrough mode even during enumeration. If this step is missing the link may not come up properly after soft-reboot for example. For this reason issue UNSET_INBOUND_SBTX after SET_INBOUND_SBTX for enumeration and also when the NVM upgrade is run. Reported-by: Christian Schaubschläger <christian.schaubschlaeger@xxxxxx> Link: https://lore.kernel.org/linux-usb/b556f5ed-5ee8-9990-9910-afd60db93310@xxxxxx/ Cc: stable@xxxxxxxxxxxxxxx Signed-off-by: Gil Fine <gil.fine@xxxxxxxxxxxxxxx> Signed-off-by: Mika Westerberg <mika.westerberg@xxxxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/thunderbolt/retimer.c | 23 +++++++++++++++++++++-- drivers/thunderbolt/sb_regs.h | 1 + drivers/thunderbolt/tb.h | 1 + drivers/thunderbolt/usb4.c | 14 ++++++++++++++ 4 files changed, 37 insertions(+), 2 deletions(-) --- a/drivers/thunderbolt/retimer.c +++ b/drivers/thunderbolt/retimer.c @@ -208,6 +208,22 @@ static ssize_t nvm_authenticate_show(str return ret; } +static void tb_retimer_set_inbound_sbtx(struct tb_port *port) +{ + int i; + + for (i = 1; i <= TB_MAX_RETIMER_INDEX; i++) + usb4_port_retimer_set_inbound_sbtx(port, i); +} + +static void tb_retimer_unset_inbound_sbtx(struct tb_port *port) +{ + int i; + + for (i = TB_MAX_RETIMER_INDEX; i >= 1; i--) + usb4_port_retimer_unset_inbound_sbtx(port, i); +} + static ssize_t nvm_authenticate_store(struct device *dev, struct device_attribute *attr, const char *buf, size_t count) { @@ -234,6 +250,7 @@ static ssize_t nvm_authenticate_store(st rt->auth_status = 0; if (val) { + tb_retimer_set_inbound_sbtx(rt->port); if (val == AUTHENTICATE_ONLY) { ret = tb_retimer_nvm_authenticate(rt, true); } else { @@ -253,6 +270,7 @@ static ssize_t nvm_authenticate_store(st } exit_unlock: + tb_retimer_unset_inbound_sbtx(rt->port); mutex_unlock(&rt->tb->lock); exit_rpm: pm_runtime_mark_last_busy(&rt->dev); @@ -466,8 +484,7 @@ int tb_retimer_scan(struct tb_port *port * Enable sideband channel for each retimer. We can do this * regardless whether there is device connected or not. */ - for (i = 1; i <= TB_MAX_RETIMER_INDEX; i++) - usb4_port_retimer_set_inbound_sbtx(port, i); + tb_retimer_set_inbound_sbtx(port); /* * Before doing anything else, read the authentication status. @@ -490,6 +507,8 @@ int tb_retimer_scan(struct tb_port *port break; } + tb_retimer_unset_inbound_sbtx(port); + if (!last_idx) return 0; --- a/drivers/thunderbolt/sb_regs.h +++ b/drivers/thunderbolt/sb_regs.h @@ -20,6 +20,7 @@ enum usb4_sb_opcode { USB4_SB_OPCODE_ROUTER_OFFLINE = 0x4e45534c, /* "LSEN" */ USB4_SB_OPCODE_ENUMERATE_RETIMERS = 0x4d554e45, /* "ENUM" */ USB4_SB_OPCODE_SET_INBOUND_SBTX = 0x5055534c, /* "LSUP" */ + USB4_SB_OPCODE_UNSET_INBOUND_SBTX = 0x50555355, /* "USUP" */ USB4_SB_OPCODE_QUERY_LAST_RETIMER = 0x5453414c, /* "LAST" */ USB4_SB_OPCODE_GET_NVM_SECTOR_SIZE = 0x53534e47, /* "GNSS" */ USB4_SB_OPCODE_NVM_SET_OFFSET = 0x53504f42, /* "BOPS" */ --- a/drivers/thunderbolt/tb.h +++ b/drivers/thunderbolt/tb.h @@ -1080,6 +1080,7 @@ int usb4_port_router_online(struct tb_po int usb4_port_enumerate_retimers(struct tb_port *port); int usb4_port_retimer_set_inbound_sbtx(struct tb_port *port, u8 index); +int usb4_port_retimer_unset_inbound_sbtx(struct tb_port *port, u8 index); int usb4_port_retimer_read(struct tb_port *port, u8 index, u8 reg, void *buf, u8 size); int usb4_port_retimer_write(struct tb_port *port, u8 index, u8 reg, --- a/drivers/thunderbolt/usb4.c +++ b/drivers/thunderbolt/usb4.c @@ -1442,6 +1442,20 @@ int usb4_port_retimer_set_inbound_sbtx(s } /** + * usb4_port_retimer_unset_inbound_sbtx() - Disable sideband channel transactions + * @port: USB4 port + * @index: Retimer index + * + * Disables sideband channel transations on SBTX. The reverse of + * usb4_port_retimer_set_inbound_sbtx(). + */ +int usb4_port_retimer_unset_inbound_sbtx(struct tb_port *port, u8 index) +{ + return usb4_port_retimer_op(port, index, + USB4_SB_OPCODE_UNSET_INBOUND_SBTX, 500); +} + +/** * usb4_port_retimer_read() - Read from retimer sideband registers * @port: USB4 port * @index: Retimer index
