Commit ec8162b3 authored by Sanath S's avatar Sanath S Committed by Mika Westerberg
Browse files

thunderbolt: Make tb_switch_reset() support Thunderbolt 2, 3 and USB4 routers 



Currently tb_switch_reset() only did something for Thunderbolt 1
devices. Expand this to support all generations, including USB4, and
both host and device routers.

Signed-off-by: default avatarSanath S <Sanath.S@amd.com>
Signed-off-by: default avatarMika Westerberg <mika.westerberg@linux.intel.com>
parent b35c1d7b

drivers/thunderbolt/switch.c

+109 −14
Original line number Diff line number Diff line
@@ -1538,21 +1538,51 @@ static void tb_dump_switch(const struct tb *tb, const struct tb_switch *sw) 
	       regs->__unknown1, regs->__unknown4);

}



/**

 * tb_switch_reset() - reconfigure route, enable and send TB_CFG_PKG_RESET

 * @sw: Switch to reset

 *

 * Return: Returns 0 on success or an error code on failure.

 */

int tb_switch_reset(struct tb_switch *sw)

static int tb_switch_reset_host(struct tb_switch *sw)

{

	struct tb_cfg_result res;

	if (sw->generation > 1) {

		struct tb_port *port;



	if (sw->generation > 1)

		return 0;

		tb_switch_for_each_port(sw, port) {

			int i, ret;



			/*

			 * For lane adapters we issue downstream port

			 * reset and clear up path config spaces.

			 *

			 * For protocol adapters we disable the path and

			 * clear path config space one by one (from 8 to

			 * Max Input HopID of the adapter).

			 */

			if (tb_port_is_null(port) && !tb_is_upstream_port(port)) {

				ret = tb_port_reset(port);

				if (ret)

					return ret;

			} else if (tb_port_is_usb3_down(port) ||

				   tb_port_is_usb3_up(port)) {

				tb_usb3_port_enable(port, false);

			} else if (tb_port_is_dpin(port) ||

				   tb_port_is_dpout(port)) {

				tb_dp_port_enable(port, false);

			} else if (tb_port_is_pcie_down(port) ||

				   tb_port_is_pcie_up(port)) {

				tb_pci_port_enable(port, false);

			} else {

				continue;

			}



	tb_sw_dbg(sw, "resetting switch\n");

			/* Cleanup path config space of protocol adapter */

			for (i = TB_PATH_MIN_HOPID;

			     i <= port->config.max_in_hop_id; i++) {

				ret = tb_path_deactivate_hop(port, i);

				if (ret)

					return ret;

			}

		}

	} else {

		struct tb_cfg_result res;



		/* Thunderbolt 1 uses the "reset" config space packet */

		res.err = tb_sw_write(sw, ((u32 *) &sw->config) + 2,

				      TB_CFG_SWITCH, 2, 2);

		if (res.err)
@@ -1560,9 +1590,74 @@ int tb_switch_reset(struct tb_switch *sw) 
		res = tb_cfg_reset(sw->tb->ctl, tb_route(sw));

		if (res.err > 0)

			return -EIO;

		else if (res.err < 0)

			return res.err;

	}



	return 0;

}



static int tb_switch_reset_device(struct tb_switch *sw)

{

	return tb_port_reset(tb_switch_downstream_port(sw));

}



static bool tb_switch_enumerated(struct tb_switch *sw)

{

	u32 val;

	int ret;



	/*

	 * Read directly from the hardware because we use this also

	 * during system sleep where sw->config.enabled is already set

	 * by us.

	 */

	ret = tb_sw_read(sw, &val, TB_CFG_SWITCH, ROUTER_CS_3, 1);

	if (ret)

		return false;



	return !!(val & ROUTER_CS_3_V);

}



/**

 * tb_switch_reset() - Perform reset to the router

 * @sw: Router to reset

 *

 * Issues reset to the router @sw. Can be used for any router. For host

 * routers, resets all the downstream ports and cleans up path config

 * spaces accordingly. For device routers issues downstream port reset

 * through the parent router, so as side effect there will be unplug

 * soon after this is finished.

 *

 * If the router is not enumerated does nothing.

 *

 * Returns %0 on success or negative errno in case of failure.

 */

int tb_switch_reset(struct tb_switch *sw)

{

	int ret;



	/*

	 * We cannot access the port config spaces unless the router is

	 * already enumerated. If the router is not enumerated it is

	 * equal to being reset so we can skip that here.

	 */

	if (!tb_switch_enumerated(sw))

		return 0;



	tb_sw_dbg(sw, "resetting\n");



	if (tb_route(sw))

		ret = tb_switch_reset_device(sw);

	else

		ret = tb_switch_reset_host(sw);



	if (ret)

		tb_sw_warn(sw, "failed to reset\n");



	return ret;

}



/**

 * tb_switch_wait_for_bit() - Wait for specified value of bits in offset

 * @sw: Router to read the offset value from

drivers/thunderbolt/tb_regs.h

+2 −0
Original line number Diff line number Diff line
@@ -194,6 +194,8 @@ struct tb_regs_switch_header { 
#define USB4_VERSION_MAJOR_MASK			GENMASK(7, 5)



#define ROUTER_CS_1				0x01

#define ROUTER_CS_3				0x03

#define ROUTER_CS_3_V				BIT(31)

#define ROUTER_CS_4				0x04

/* Used with the router cmuv field */

#define ROUTER_CS_4_CMUV_V1			0x10