Re: [PATCH v2 4/9] thunderbolt: Add initial support for USB4

From: Nicholas Johnson
Date: Wed Dec 18 2019 - 04:35:08 EST


On Tue, Dec 17, 2019 at 03:33:40PM +0300, Mika Westerberg wrote:
> USB4 is the public specification based on Thunderbolt 3 protocol. There
> are some differences in register layouts and flows. In addition to PCIe
> and DP tunneling, USB4 supports tunneling of USB 3.x. USB4 is also
> backward compatible with Thunderbolt 3 (and older generations but the
> spec only talks about 3rd generation). USB4 compliant devices can be
> identified by checking USB4 version field in router configuration space.
>
> This patch adds initial support for USB4 compliant hosts and devices
> which enables following features provided by the existing functionality
> in the driver:
>
> - PCIe tunneling
> - Display Port tunneling
Nitpick: DisplayPort is a single word.

> - Host and device NVM firmware upgrade
> - P2P networking
>
> This brings the USB4 support to the same level that we already have for
> Thunderbolt 1, 2 and 3 devices.
>
> Note the spec talks about host and device "routers" but in the driver we
> still use term "switch" in most places. Both can be used interchangeably.
>
> Co-developed-by: Rajmohan Mani <rajmohan.mani@xxxxxxxxx>
> Signed-off-by: Rajmohan Mani <rajmohan.mani@xxxxxxxxx>
> Signed-off-by: Mika Westerberg <mika.westerberg@xxxxxxxxxxxxxxx>
> ---
> drivers/thunderbolt/Makefile | 2 +-
> drivers/thunderbolt/eeprom.c | 53 ++-
> drivers/thunderbolt/nhi.c | 3 +
> drivers/thunderbolt/nhi.h | 2 +
> drivers/thunderbolt/switch.c | 382 +++++++++++++-----
> drivers/thunderbolt/tb.c | 20 +-
> drivers/thunderbolt/tb.h | 36 ++
> drivers/thunderbolt/tb_regs.h | 36 +-
> drivers/thunderbolt/tunnel.c | 11 +-
> drivers/thunderbolt/usb4.c | 724 ++++++++++++++++++++++++++++++++++
> drivers/thunderbolt/xdomain.c | 6 +
> 11 files changed, 1158 insertions(+), 117 deletions(-)
> create mode 100644 drivers/thunderbolt/usb4.c
>
> diff --git a/drivers/thunderbolt/Makefile b/drivers/thunderbolt/Makefile
> index 001187c577bf..c0b2fd73dfbd 100644
> --- a/drivers/thunderbolt/Makefile
> +++ b/drivers/thunderbolt/Makefile
> @@ -1,4 +1,4 @@
> # SPDX-License-Identifier: GPL-2.0-only
> obj-${CONFIG_THUNDERBOLT} := thunderbolt.o
> thunderbolt-objs := nhi.o nhi_ops.o ctl.o tb.o switch.o cap.o path.o tunnel.o eeprom.o
> -thunderbolt-objs += domain.o dma_port.o icm.o property.o xdomain.o lc.o
> +thunderbolt-objs += domain.o dma_port.o icm.o property.o xdomain.o lc.o usb4.o
> diff --git a/drivers/thunderbolt/eeprom.c b/drivers/thunderbolt/eeprom.c
> index 540e0105bcc0..921d164b3f35 100644
> --- a/drivers/thunderbolt/eeprom.c
> +++ b/drivers/thunderbolt/eeprom.c
> @@ -487,6 +487,37 @@ static int tb_drom_copy_nvm(struct tb_switch *sw, u16 *size)
> return ret;
> }
>
> +static int usb4_copy_host_drom(struct tb_switch *sw, u16 *size)
> +{
> + int ret;
> +
> + ret = usb4_switch_drom_read(sw, 14, size, sizeof(*size));
> + if (ret)
> + return ret;
> +
> + /* Size includes CRC8 + UID + CRC32 */
> + *size += 1 + 8 + 4;
> + sw->drom = kzalloc(*size, GFP_KERNEL);
> + if (!sw->drom)
> + return -ENOMEM;
> +
> + ret = usb4_switch_drom_read(sw, 0, sw->drom, *size);
> + if (ret) {
> + kfree(sw->drom);
> + sw->drom = NULL;
> + }
> +
> + return ret;
> +}
> +
> +static int tb_drom_read_n(struct tb_switch *sw, u16 offset, u8 *val,
> + size_t count)
> +{
> + if (tb_switch_is_usb4(sw))
> + return usb4_switch_drom_read(sw, offset, val, count);
> + return tb_eeprom_read_n(sw, offset, val, count);
> +}
> +
> /**
> * tb_drom_read - copy drom to sw->drom and parse it
> */
> @@ -512,14 +543,26 @@ int tb_drom_read(struct tb_switch *sw)
> goto parse;
>
> /*
> - * The root switch contains only a dummy drom (header only,
> - * no entries). Hardcode the configuration here.
> + * USB4 hosts may support reading DROM through router
> + * operations.
> */
> - tb_drom_read_uid_only(sw, &sw->uid);
> + if (tb_switch_is_usb4(sw)) {
> + usb4_switch_read_uid(sw, &sw->uid);
> + if (!usb4_copy_host_drom(sw, &size))
> + goto parse;
> + } else {
> + /*
> + * The root switch contains only a dummy drom
> + * (header only, no entries). Hardcode the
> + * configuration here.
> + */
> + tb_drom_read_uid_only(sw, &sw->uid);
> + }
> +
> return 0;
> }
>
> - res = tb_eeprom_read_n(sw, 14, (u8 *) &size, 2);
> + res = tb_drom_read_n(sw, 14, (u8 *) &size, 2);
> if (res)
> return res;
> size &= 0x3ff;
> @@ -533,7 +576,7 @@ int tb_drom_read(struct tb_switch *sw)
> sw->drom = kzalloc(size, GFP_KERNEL);
> if (!sw->drom)
> return -ENOMEM;
> - res = tb_eeprom_read_n(sw, 0, sw->drom, size);
> + res = tb_drom_read_n(sw, 0, sw->drom, size);
> if (res)
> goto err;
>
> diff --git a/drivers/thunderbolt/nhi.c b/drivers/thunderbolt/nhi.c
> index 641b21b54460..1be491ecbb45 100644
> --- a/drivers/thunderbolt/nhi.c
> +++ b/drivers/thunderbolt/nhi.c
> @@ -1271,6 +1271,9 @@ static struct pci_device_id nhi_ids[] = {
> { PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_ICL_NHI1),
> .driver_data = (kernel_ulong_t)&icl_nhi_ops },
>
> + /* Any USB4 compliant host */
> + { PCI_DEVICE_CLASS(PCI_CLASS_SERIAL_USB_USB4, ~0) },
> +
> { 0,}
> };
>
> diff --git a/drivers/thunderbolt/nhi.h b/drivers/thunderbolt/nhi.h
> index b7b973949f8e..5d276ee9b38e 100644
> --- a/drivers/thunderbolt/nhi.h
> +++ b/drivers/thunderbolt/nhi.h
> @@ -74,4 +74,6 @@ extern const struct tb_nhi_ops icl_nhi_ops;
> #define PCI_DEVICE_ID_INTEL_ICL_NHI1 0x8a0d
> #define PCI_DEVICE_ID_INTEL_ICL_NHI0 0x8a17
>
> +#define PCI_CLASS_SERIAL_USB_USB4 0x0c0340
> +
> #endif
> diff --git a/drivers/thunderbolt/switch.c b/drivers/thunderbolt/switch.c
> index 9c72521cb298..c1d5cd7e0631 100644
> --- a/drivers/thunderbolt/switch.c
> +++ b/drivers/thunderbolt/switch.c
> @@ -163,10 +163,12 @@ static int nvm_validate_and_write(struct tb_switch *sw)
> image_size -= hdr_size;
> }
>
> + if (tb_switch_is_usb4(sw))
> + return usb4_switch_nvm_write(sw, 0, buf, image_size);
> return dma_port_flash_write(sw->dma_port, 0, buf, image_size);
> }
>
> -static int nvm_authenticate_host(struct tb_switch *sw)
> +static int nvm_authenticate_host_dma_port(struct tb_switch *sw)
> {
> int ret = 0;
>
> @@ -206,7 +208,7 @@ static int nvm_authenticate_host(struct tb_switch *sw)
> return ret;
> }
>
> -static int nvm_authenticate_device(struct tb_switch *sw)
> +static int nvm_authenticate_device_dma_port(struct tb_switch *sw)
> {
> int ret, retries = 10;
>
> @@ -251,6 +253,78 @@ static int nvm_authenticate_device(struct tb_switch *sw)
> return -ETIMEDOUT;
> }
>
> +static void nvm_authenticate_start_dma_port(struct tb_switch *sw)
> +{
> + struct pci_dev *root_port;
> +
> + /*
> + * During host router NVM upgrade we should not allow root port to
> + * go into D3cold because some root ports cannot trigger PME
> + * itself. To be on the safe side keep the root port in D0 during
> + * the whole upgrade process.
> + */
> + root_port = pci_find_pcie_root_port(sw->tb->nhi->pdev);
> + if (root_port)
> + pm_runtime_get_noresume(&root_port->dev);
> +}
> +
> +static void nvm_authenticate_complete_dma_port(struct tb_switch *sw)
> +{
> + struct pci_dev *root_port;
> +
> + root_port = pci_find_pcie_root_port(sw->tb->nhi->pdev);
> + if (root_port)
> + pm_runtime_put(&root_port->dev);
> +}
> +
> +static inline bool nvm_readable(struct tb_switch *sw)
> +{
> + if (tb_switch_is_usb4(sw)) {
> + /*
> + * USB4 devices must support NVM operations but it is
> + * optional for hosts. Therefore we query the NVM sector
> + * size here and if it is supported assume NVM
> + * operations are implemented.
> + */
> + return usb4_switch_nvm_sector_size(sw) > 0;
> + }
> +
> + /* Thunderbolt 2 and 3 devices support NVM through DMA port */
> + return !!sw->dma_port;
> +}
> +
> +static inline bool nvm_upgradeable(struct tb_switch *sw)
> +{
> + if (sw->no_nvm_upgrade)
> + return false;
> + return nvm_readable(sw);
> +}
> +
> +static inline int nvm_read(struct tb_switch *sw, unsigned int address,
> + void *buf, size_t size)
> +{
> + if (tb_switch_is_usb4(sw))
> + return usb4_switch_nvm_read(sw, address, buf, size);
> + return dma_port_flash_read(sw->dma_port, address, buf, size);
> +}
> +
> +static int nvm_authenticate(struct tb_switch *sw)
> +{
> + int ret;
> +
> + if (tb_switch_is_usb4(sw))
> + return usb4_switch_nvm_authenticate(sw);
> +
> + if (!tb_route(sw)) {
> + nvm_authenticate_start_dma_port(sw);
> + ret = nvm_authenticate_host_dma_port(sw);
> + } else {
> + ret = nvm_authenticate_device_dma_port(sw);
> + }
> +
> + return ret;
> +}
> +
> static int tb_switch_nvm_read(void *priv, unsigned int offset, void *val,
> size_t bytes)
> {
> @@ -264,7 +338,7 @@ static int tb_switch_nvm_read(void *priv, unsigned int offset, void *val,
> goto out;
> }
>
> - ret = dma_port_flash_read(sw->dma_port, offset, val, bytes);
> + ret = nvm_read(sw, offset, val, bytes);
> mutex_unlock(&sw->tb->lock);
>
> out:
> @@ -341,9 +415,21 @@ static int tb_switch_nvm_add(struct tb_switch *sw)
> u32 val;
> int ret;
>
> - if (!sw->dma_port)
> + if (!nvm_readable(sw))
> return 0;
>
> + /*
> + * The NVM format of non-Intel hardware is not known so
> + * currently restrict NVM upgrade for Intel hardware. We may
> + * relax this in the future when we learn other NVM formats.
> + */
> + if (sw->config.vendor_id != PCI_VENDOR_ID_INTEL) {
> + dev_info(&sw->dev,
> + "NVM format of vendor %#x is not known, disabling NVM upgrade\n",
> + sw->config.vendor_id);
> + return 0;
> + }
> +
> nvm = kzalloc(sizeof(*nvm), GFP_KERNEL);
> if (!nvm)
> return -ENOMEM;
> @@ -358,8 +444,7 @@ static int tb_switch_nvm_add(struct tb_switch *sw)
> if (!sw->safe_mode) {
> u32 nvm_size, hdr_size;
>
> - ret = dma_port_flash_read(sw->dma_port, NVM_FLASH_SIZE, &val,
> - sizeof(val));
> + ret = nvm_read(sw, NVM_FLASH_SIZE, &val, sizeof(val));
> if (ret)
> goto err_ida;
>
> @@ -367,8 +452,7 @@ static int tb_switch_nvm_add(struct tb_switch *sw)
> nvm_size = (SZ_1M << (val & 7)) / 8;
> nvm_size = (nvm_size - hdr_size) / 2;
>
> - ret = dma_port_flash_read(sw->dma_port, NVM_VERSION, &val,
> - sizeof(val));
> + ret = nvm_read(sw, NVM_VERSION, &val, sizeof(val));
> if (ret)
> goto err_ida;
>
> @@ -619,6 +703,24 @@ int tb_port_clear_counter(struct tb_port *port, int counter)
> return tb_port_write(port, zero, TB_CFG_COUNTERS, 3 * counter, 3);
> }
>
> +/**
> + * tb_port_unlock() - Unlock downstream port
> + * @port: Port to unlock
> + *
> + * Needed for USB4 but can be called for any CIO/USB4 ports. Makes the
> + * downstream router accessible for CM.
> + */
> +int tb_port_unlock(struct tb_port *port)
> +{
> + if (tb_switch_is_icm(port->sw))
> + return 0;
> + if (!tb_port_is_null(port))
> + return -EINVAL;
> + if (tb_switch_is_usb4(port->sw))
> + return usb4_port_unlock(port);
> + return 0;
> +}
> +
> /**
> * tb_init_port() - initialize a port
> *
> @@ -650,6 +752,10 @@ static int tb_init_port(struct tb_port *port)
> port->cap_phy = cap;
> else
> tb_port_WARN(port, "non switch port without a PHY\n");
> +
> + cap = tb_port_find_cap(port, TB_PORT_CAP_USB4);
> + if (cap > 0)
> + port->cap_usb4 = cap;
> } else if (port->port != 0) {
> cap = tb_port_find_cap(port, TB_PORT_CAP_ADAP);
> if (cap > 0)
> @@ -1088,20 +1194,38 @@ int tb_dp_port_enable(struct tb_port *port, bool enable)
>
> /* switch utility functions */
>
> -static void tb_dump_switch(struct tb *tb, struct tb_regs_switch_header *sw)
> +static const char *tb_switch_generation_name(const struct tb_switch *sw)
> +{
> + switch (sw->generation) {
> + case 1:
> + return "Thunderbolt 1";
> + case 2:
> + return "Thunderbolt 2";
> + case 3:
> + return "Thunderbolt 3";
> + case 4:
> + return "USB4";
> + default:
> + return "Unknown";
> + }
> +}
> +
> +static void tb_dump_switch(const struct tb *tb, const struct tb_switch *sw)
> {
> - tb_dbg(tb, " Switch: %x:%x (Revision: %d, TB Version: %d)\n",
> - sw->vendor_id, sw->device_id, sw->revision,
> - sw->thunderbolt_version);
> - tb_dbg(tb, " Max Port Number: %d\n", sw->max_port_number);
> + const struct tb_regs_switch_header *regs = &sw->config;
> +
> + tb_dbg(tb, " %s Switch: %x:%x (Revision: %d, TB Version: %d)\n",
> + tb_switch_generation_name(sw), regs->vendor_id, regs->device_id,
> + regs->revision, regs->thunderbolt_version);
> + tb_dbg(tb, " Max Port Number: %d\n", regs->max_port_number);
> tb_dbg(tb, " Config:\n");
> tb_dbg(tb,
> " Upstream Port Number: %d Depth: %d Route String: %#llx Enabled: %d, PlugEventsDelay: %dms\n",
> - sw->upstream_port_number, sw->depth,
> - (((u64) sw->route_hi) << 32) | sw->route_lo,
> - sw->enabled, sw->plug_events_delay);
> + regs->upstream_port_number, regs->depth,
> + (((u64) regs->route_hi) << 32) | regs->route_lo,
> + regs->enabled, regs->plug_events_delay);
> tb_dbg(tb, " unknown1: %#x unknown4: %#x\n",
> - sw->__unknown1, sw->__unknown4);
> + regs->__unknown1, regs->__unknown4);
> }
>
> /**
> @@ -1148,6 +1272,10 @@ static int tb_plug_events_active(struct tb_switch *sw, bool active)
> if (res)
> return res;
>
> + /* Plug events are always enabled in USB4 */
> + if (tb_switch_is_usb4(sw))
> + return 0;
> +
> res = tb_sw_read(sw, &data, TB_CFG_SWITCH, sw->cap_plug_events + 1, 1);
> if (res)
> return res;
> @@ -1359,30 +1487,6 @@ static ssize_t lanes_show(struct device *dev, struct device_attribute *attr,
> static DEVICE_ATTR(rx_lanes, 0444, lanes_show, NULL);
> static DEVICE_ATTR(tx_lanes, 0444, lanes_show, NULL);
>
> -static void nvm_authenticate_start(struct tb_switch *sw)
> -{
> - struct pci_dev *root_port;
> -
> - /*
> - * During host router NVM upgrade we should not allow root port to
> - * go into D3cold because some root ports cannot trigger PME
> - * itself. To be on the safe side keep the root port in D0 during
> - * the whole upgrade process.
> - */
> - root_port = pci_find_pcie_root_port(sw->tb->nhi->pdev);
> - if (root_port)
> - pm_runtime_get_noresume(&root_port->dev);
> -}
> -
> -static void nvm_authenticate_complete(struct tb_switch *sw)
> -{
> - struct pci_dev *root_port;
> -
> - root_port = pci_find_pcie_root_port(sw->tb->nhi->pdev);
> - if (root_port)
> - pm_runtime_put(&root_port->dev);
> -}
> -
> static ssize_t nvm_authenticate_show(struct device *dev,
> struct device_attribute *attr, char *buf)
> {
> @@ -1431,17 +1535,7 @@ static ssize_t nvm_authenticate_store(struct device *dev,
> goto exit_unlock;
>
> sw->nvm->authenticating = true;
> -
> - if (!tb_route(sw)) {
> - /*
> - * Keep root port from suspending as long as the
> - * NVM upgrade process is running.
> - */
> - nvm_authenticate_start(sw);
> - ret = nvm_authenticate_host(sw);
> - } else {
> - ret = nvm_authenticate_device(sw);
> - }
> + ret = nvm_authenticate(sw);
> }
>
> exit_unlock:
> @@ -1556,11 +1650,11 @@ static umode_t switch_attr_is_visible(struct kobject *kobj,
> return attr->mode;
> return 0;
> } else if (attr == &dev_attr_nvm_authenticate.attr) {
> - if (sw->dma_port && !sw->no_nvm_upgrade)
> + if (nvm_upgradeable(sw))
> return attr->mode;
> return 0;
> } else if (attr == &dev_attr_nvm_version.attr) {
> - if (sw->dma_port)
> + if (nvm_readable(sw))
> return attr->mode;
> return 0;
> } else if (attr == &dev_attr_boot.attr) {
> @@ -1672,6 +1766,9 @@ static int tb_switch_get_generation(struct tb_switch *sw)
> return 3;
>
> default:
> + if (tb_switch_is_usb4(sw))
> + return 4;
> +
> /*
> * For unknown switches assume generation to be 1 to be
> * on the safe side.
> @@ -1682,6 +1779,19 @@ static int tb_switch_get_generation(struct tb_switch *sw)
> }
> }
>
> +static bool tb_switch_exceeds_max_depth(const struct tb_switch *sw, int depth)
> +{
> + int max_depth;
> +
> + if (tb_switch_is_usb4(sw) ||
> + (sw->tb->root_switch && tb_switch_is_usb4(sw->tb->root_switch)))
> + max_depth = USB4_SWITCH_MAX_DEPTH;
> + else
> + max_depth = TB_SWITCH_MAX_DEPTH;
> +
> + return depth > max_depth;
> +}
> +
> /**
> * tb_switch_alloc() - allocate a switch
> * @tb: Pointer to the owning domain
> @@ -1703,10 +1813,16 @@ struct tb_switch *tb_switch_alloc(struct tb *tb, struct device *parent,
> int upstream_port;
> int i, ret, depth;
>
> - /* Make sure we do not exceed maximum topology limit */
> + /* Unlock the downstream port so we can access the switch below */
> + if (route) {
> + struct tb_switch *parent_sw = tb_to_switch(parent);
> + struct tb_port *down;
> +
> + down = tb_port_at(route, parent_sw);
> + tb_port_unlock(down);
> + }
> +
> depth = tb_route_length(route);
> - if (depth > TB_SWITCH_MAX_DEPTH)
> - return ERR_PTR(-EADDRNOTAVAIL);
>
> upstream_port = tb_cfg_get_upstream_port(tb->ctl, route);
> if (upstream_port < 0)
> @@ -1721,8 +1837,10 @@ struct tb_switch *tb_switch_alloc(struct tb *tb, struct device *parent,
> if (ret)
> goto err_free_sw_ports;
>
> + sw->generation = tb_switch_get_generation(sw);
> +
> tb_dbg(tb, "current switch config:\n");
> - tb_dump_switch(tb, &sw->config);
> + tb_dump_switch(tb, sw);
>
> /* configure switch */
> sw->config.upstream_port_number = upstream_port;
> @@ -1731,6 +1849,10 @@ struct tb_switch *tb_switch_alloc(struct tb *tb, struct device *parent,
> sw->config.route_lo = lower_32_bits(route);
> sw->config.enabled = 0;
>
> + /* Make sure we do not exceed maximum topology limit */
> + if (tb_switch_exceeds_max_depth(sw, depth))
> + return ERR_PTR(-EADDRNOTAVAIL);
> +
> /* initialize ports */
> sw->ports = kcalloc(sw->config.max_port_number + 1, sizeof(*sw->ports),
> GFP_KERNEL);
> @@ -1745,14 +1867,9 @@ struct tb_switch *tb_switch_alloc(struct tb *tb, struct device *parent,
> sw->ports[i].port = i;
> }
>
> - sw->generation = tb_switch_get_generation(sw);
> -
> ret = tb_switch_find_vse_cap(sw, TB_VSE_CAP_PLUG_EVENTS);
> - if (ret < 0) {
> - tb_sw_warn(sw, "cannot find TB_VSE_CAP_PLUG_EVENTS aborting\n");
> - goto err_free_sw_ports;
> - }
> - sw->cap_plug_events = ret;
> + if (ret > 0)
> + sw->cap_plug_events = ret;
>
> ret = tb_switch_find_vse_cap(sw, TB_VSE_CAP_LINK_CONTROLLER);
> if (ret > 0)
> @@ -1823,7 +1940,8 @@ tb_switch_alloc_safe_mode(struct tb *tb, struct device *parent, u64 route)
> *
> * Call this function before the switch is added to the system. It will
> * upload configuration to the switch and makes it available for the
> - * connection manager to use.
> + * connection manager to use. Can be called to the switch again after
> + * resume from low power states to re-initialize it.
> *
> * Return: %0 in case of success and negative errno in case of failure
> */
> @@ -1834,21 +1952,50 @@ int tb_switch_configure(struct tb_switch *sw)
> int ret;
>
> route = tb_route(sw);
> - tb_dbg(tb, "initializing Switch at %#llx (depth: %d, up port: %d)\n",
> - route, tb_route_length(route), sw->config.upstream_port_number);
>
> - if (sw->config.vendor_id != PCI_VENDOR_ID_INTEL)
> - tb_sw_warn(sw, "unknown switch vendor id %#x\n",
> - sw->config.vendor_id);
> + tb_dbg(tb, "%s Switch at %#llx (depth: %d, up port: %d)\n",
> + sw->config.enabled ? "restoring " : "initializing", route,
> + tb_route_length(route), sw->config.upstream_port_number);
>
> sw->config.enabled = 1;
>
> - /* upload configuration */
> - ret = tb_sw_write(sw, 1 + (u32 *)&sw->config, TB_CFG_SWITCH, 1, 3);
> - if (ret)
> - return ret;
> + if (tb_switch_is_usb4(sw)) {
> + /*
> + * For USB4 devices, we need to program the CM version
> + * accordingly so that it knows to expose all the
> + * additional capabilities.
> + */
> + sw->config.cmuv = USB4_VERSION_1_0;
> +
> + /* Enumerate the switch */
> + ret = tb_sw_write(sw, (u32 *)&sw->config + 1, TB_CFG_SWITCH,
> + ROUTER_CS_1, 4);
> + if (ret)
> + return ret;
>
> - ret = tb_lc_configure_link(sw);
> + ret = usb4_switch_setup(sw);
> + if (ret)
> + return ret;
> +
> + ret = usb4_switch_configure_link(sw);
> + } else {
> + if (sw->config.vendor_id != PCI_VENDOR_ID_INTEL)
> + tb_sw_warn(sw, "unknown switch vendor id %#x\n",
> + sw->config.vendor_id);
> +
> + if (!sw->cap_plug_events) {
> + tb_sw_warn(sw, "cannot find TB_VSE_CAP_PLUG_EVENTS aborting\n");
> + return -ENODEV;
> + }
> +
> + /* Enumerate the switch */
> + ret = tb_sw_write(sw, (u32 *)&sw->config + 1, TB_CFG_SWITCH,
> + ROUTER_CS_1, 3);
> + if (ret)
> + return ret;
> +
> + ret = tb_lc_configure_link(sw);
> + }
> if (ret)
> return ret;
>
> @@ -1857,18 +2004,32 @@ int tb_switch_configure(struct tb_switch *sw)
>
> static int tb_switch_set_uuid(struct tb_switch *sw)
> {
> + bool uid = false;
> u32 uuid[4];
> int ret;
>
> if (sw->uuid)
> return 0;
>
> - /*
> - * The newer controllers include fused UUID as part of link
> - * controller specific registers
> - */
> - ret = tb_lc_read_uuid(sw, uuid);
> - if (ret) {
> + if (tb_switch_is_usb4(sw)) {
> + ret = usb4_switch_read_uid(sw, &sw->uid);
> + if (ret)
> + return ret;
> + uid = true;
> + } else {
> + /*
> + * The newer controllers include fused UUID as part of
> + * link controller specific registers
> + */
> + ret = tb_lc_read_uuid(sw, uuid);
> + if (ret) {
> + if (ret != -EINVAL)
> + return ret;
> + uid = true;
> + }
> + }
> +
> + if (uid) {
> /*
> * ICM generates UUID based on UID and fills the upper
> * two words with ones. This is not strictly following
> @@ -1935,7 +2096,7 @@ static int tb_switch_add_dma_port(struct tb_switch *sw)
> nvm_get_auth_status(sw, &status);
> if (status) {
> if (!tb_route(sw))
> - nvm_authenticate_complete(sw);
> + nvm_authenticate_complete_dma_port(sw);
> return 0;
> }
>
> @@ -1950,7 +2111,7 @@ static int tb_switch_add_dma_port(struct tb_switch *sw)
>
> /* Now we can allow root port to suspend again */
> if (!tb_route(sw))
> - nvm_authenticate_complete(sw);
> + nvm_authenticate_complete_dma_port(sw);
>
> if (status) {
> tb_sw_info(sw, "switch flash authentication failed\n");
> @@ -2004,6 +2165,8 @@ static bool tb_switch_lane_bonding_possible(struct tb_switch *sw)
> if (!up->dual_link_port || !up->dual_link_port->remote)
> return false;
>
> + if (tb_switch_is_usb4(sw))
> + return usb4_switch_lane_bonding_possible(sw);
> return tb_lc_lane_bonding_possible(sw);
> }
>
> @@ -2240,7 +2403,11 @@ void tb_switch_remove(struct tb_switch *sw)
>
> if (!sw->is_unplugged)
> tb_plug_events_active(sw, false);
> - tb_lc_unconfigure_link(sw);
> +
> + if (tb_switch_is_usb4(sw))
> + usb4_switch_unconfigure_link(sw);
> + else
> + tb_lc_unconfigure_link(sw);
>
> tb_switch_nvm_remove(sw);
>
> @@ -2298,7 +2465,10 @@ int tb_switch_resume(struct tb_switch *sw)
> return err;
> }
>
> - err = tb_drom_read_uid_only(sw, &uid);
> + if (tb_switch_is_usb4(sw))
> + err = usb4_switch_read_uid(sw, &uid);
> + else
> + err = tb_drom_read_uid_only(sw, &uid);
> if (err) {
> tb_sw_warn(sw, "uid read failed\n");
> return err;
> @@ -2311,16 +2481,7 @@ int tb_switch_resume(struct tb_switch *sw)
> }
> }
>
> - /* upload configuration */
> - err = tb_sw_write(sw, 1 + (u32 *) &sw->config, TB_CFG_SWITCH, 1, 3);
> - if (err)
> - return err;
> -
> - err = tb_lc_configure_link(sw);
> - if (err)
> - return err;
> -
> - err = tb_plug_events_active(sw, true);
> + err = tb_switch_configure(sw);
> if (err)
> return err;
>
> @@ -2336,8 +2497,14 @@ int tb_switch_resume(struct tb_switch *sw)
> tb_sw_set_unplugged(port->remote->sw);
> else if (port->xdomain)
> port->xdomain->is_unplugged = true;
> - } else if (tb_port_has_remote(port)) {
> - if (tb_switch_resume(port->remote->sw)) {
> + } else if (tb_port_has_remote(port) || port->xdomain) {
> + /*
> + * Always unlock the port so the downstream
> + * switch/domain is accessible.
> + */
> + if (tb_port_unlock(port))
> + tb_port_warn(port, "failed to unlock port\n");
> + if (port->remote && tb_switch_resume(port->remote->sw)) {
> tb_port_warn(port,
> "lost during suspend, disconnecting\n");
> tb_sw_set_unplugged(port->remote->sw);
> @@ -2361,7 +2528,10 @@ void tb_switch_suspend(struct tb_switch *sw)
> tb_switch_suspend(port->remote->sw);
> }
>
> - tb_lc_set_sleep(sw);
> + if (tb_switch_is_usb4(sw))
> + usb4_switch_set_sleep(sw);
> + else
> + tb_lc_set_sleep(sw);
> }
>
> /**
> @@ -2374,6 +2544,8 @@ void tb_switch_suspend(struct tb_switch *sw)
> */
> bool tb_switch_query_dp_resource(struct tb_switch *sw, struct tb_port *in)
> {
> + if (tb_switch_is_usb4(sw))
> + return usb4_switch_query_dp_resource(sw, in);
> return tb_lc_dp_sink_query(sw, in);
> }
>
> @@ -2388,6 +2560,8 @@ bool tb_switch_query_dp_resource(struct tb_switch *sw, struct tb_port *in)
> */
> int tb_switch_alloc_dp_resource(struct tb_switch *sw, struct tb_port *in)
> {
> + if (tb_switch_is_usb4(sw))
> + return usb4_switch_alloc_dp_resource(sw, in);
> return tb_lc_dp_sink_alloc(sw, in);
> }
>
> @@ -2401,10 +2575,16 @@ int tb_switch_alloc_dp_resource(struct tb_switch *sw, struct tb_port *in)
> */
> void tb_switch_dealloc_dp_resource(struct tb_switch *sw, struct tb_port *in)
> {
> - if (tb_lc_dp_sink_dealloc(sw, in)) {
> + int ret;
> +
> + if (tb_switch_is_usb4(sw))
> + ret = usb4_switch_dealloc_dp_resource(sw, in);
> + else
> + ret = tb_lc_dp_sink_dealloc(sw, in);
> +
> + if (ret)
> tb_sw_warn(sw, "failed to de-allocate DP resource for port %d\n",
> in->port);
> - }
> }
>
> struct tb_sw_lookup {
> diff --git a/drivers/thunderbolt/tb.c b/drivers/thunderbolt/tb.c
> index e54d0d89a32d..6b99dcd1790c 100644
> --- a/drivers/thunderbolt/tb.c
> +++ b/drivers/thunderbolt/tb.c
> @@ -365,12 +365,15 @@ static struct tb_port *tb_find_unused_port(struct tb_switch *sw,
> static struct tb_port *tb_find_pcie_down(struct tb_switch *sw,
> const struct tb_port *port)
> {
> + struct tb_port *down = NULL;
> +
> /*
> * To keep plugging devices consistently in the same PCIe
> - * hierarchy, do mapping here for root switch downstream PCIe
> - * ports.
> + * hierarchy, do mapping here for switch downstream PCIe ports.
> */
> - if (!tb_route(sw)) {
> + if (tb_switch_is_usb4(sw)) {
> + down = usb4_switch_map_pcie_down(sw, port);
> + } else if (!tb_route(sw)) {
> int phy_port = tb_phy_port_from_link(port->port);
> int index;
>
> @@ -391,12 +394,17 @@ static struct tb_port *tb_find_pcie_down(struct tb_switch *sw,
> /* Validate the hard-coding */
> if (WARN_ON(index > sw->config.max_port_number))
> goto out;
> - if (WARN_ON(!tb_port_is_pcie_down(&sw->ports[index])))
> +
> + down = &sw->ports[index];
> + }
> +
> + if (down) {
> + if (WARN_ON(!tb_port_is_pcie_down(down)))
> goto out;
> - if (WARN_ON(tb_pci_port_is_enabled(&sw->ports[index])))
> + if (WARN_ON(tb_pci_port_is_enabled(down)))
> goto out;
>
> - return &sw->ports[index];
> + return down;
> }
>
> out:
> diff --git a/drivers/thunderbolt/tb.h b/drivers/thunderbolt/tb.h
> index ade1c7c77db1..0158f0e9858c 100644
> --- a/drivers/thunderbolt/tb.h
> +++ b/drivers/thunderbolt/tb.h
> @@ -44,6 +44,7 @@ struct tb_switch_nvm {
>
> #define TB_SWITCH_KEY_SIZE 32
> #define TB_SWITCH_MAX_DEPTH 6
> +#define USB4_SWITCH_MAX_DEPTH 5
>
> /**
> * struct tb_switch - a thunderbolt switch
> @@ -129,6 +130,7 @@ struct tb_switch {
> * @xdomain: Remote host (%NULL if not connected)
> * @cap_phy: Offset, zero if not found
> * @cap_adap: Offset of the adapter specific capability (%0 if not present)
> + * @cap_usb4: Offset to the USB4 port capability (%0 if not present)
> * @port: Port number on switch
> * @disabled: Disabled by eeprom
> * @bonded: true if the port is bonded (two lanes combined as one)
> @@ -146,6 +148,7 @@ struct tb_port {
> struct tb_xdomain *xdomain;
> int cap_phy;
> int cap_adap;
> + int cap_usb4;
> u8 port;
> bool disabled;
> bool bonded;
> @@ -637,6 +640,17 @@ static inline bool tb_switch_is_titan_ridge(const struct tb_switch *sw)
> }
> }
>
> +/**
> + * tb_switch_is_usb4() - Is the switch USB4 compliant
> + * @sw: Switch to check
> + *
> + * Returns true if the @sw is USB4 compliant router, false otherwise.
> + */
> +static inline bool tb_switch_is_usb4(const struct tb_switch *sw)
> +{
> + return sw->config.thunderbolt_version == USB4_VERSION_1_0;
> +}
> +
> /**
> * tb_switch_is_icm() - Is the switch handled by ICM firmware
> * @sw: Switch to check
> @@ -662,6 +676,7 @@ int tb_wait_for_port(struct tb_port *port, bool wait_if_unplugged);
> int tb_port_add_nfc_credits(struct tb_port *port, int credits);
> int tb_port_set_initial_credits(struct tb_port *port, u32 credits);
> int tb_port_clear_counter(struct tb_port *port, int counter);
> +int tb_port_unlock(struct tb_port *port);
> int tb_port_alloc_in_hopid(struct tb_port *port, int hopid, int max_hopid);
> void tb_port_release_in_hopid(struct tb_port *port, int hopid);
> int tb_port_alloc_out_hopid(struct tb_port *port, int hopid, int max_hopid);
> @@ -736,4 +751,25 @@ void tb_xdomain_remove(struct tb_xdomain *xd);
> struct tb_xdomain *tb_xdomain_find_by_link_depth(struct tb *tb, u8 link,
> u8 depth);
>
> +int usb4_switch_setup(struct tb_switch *sw);
> +int usb4_switch_read_uid(struct tb_switch *sw, u64 *uid);
> +int usb4_switch_drom_read(struct tb_switch *sw, unsigned int address, void *buf,
> + size_t size);
> +int usb4_switch_configure_link(struct tb_switch *sw);
> +void usb4_switch_unconfigure_link(struct tb_switch *sw);
> +bool usb4_switch_lane_bonding_possible(struct tb_switch *sw);
> +int usb4_switch_set_sleep(struct tb_switch *sw);
> +int usb4_switch_nvm_sector_size(struct tb_switch *sw);
> +int usb4_switch_nvm_read(struct tb_switch *sw, unsigned int address, void *buf,
> + size_t size);
> +int usb4_switch_nvm_write(struct tb_switch *sw, unsigned int address,
> + const void *buf, size_t size);
> +int usb4_switch_nvm_authenticate(struct tb_switch *sw);
> +bool usb4_switch_query_dp_resource(struct tb_switch *sw, struct tb_port *in);
> +int usb4_switch_alloc_dp_resource(struct tb_switch *sw, struct tb_port *in);
> +int usb4_switch_dealloc_dp_resource(struct tb_switch *sw, struct tb_port *in);
> +struct tb_port *usb4_switch_map_pcie_down(struct tb_switch *sw,
> + const struct tb_port *port);
> +
> +int usb4_port_unlock(struct tb_port *port);
> #endif
> diff --git a/drivers/thunderbolt/tb_regs.h b/drivers/thunderbolt/tb_regs.h
> index 7ee45b73c7f7..47f73f992412 100644
> --- a/drivers/thunderbolt/tb_regs.h
> +++ b/drivers/thunderbolt/tb_regs.h
> @@ -41,6 +41,7 @@ enum tb_port_cap {
> TB_PORT_CAP_TIME1 = 0x03,
> TB_PORT_CAP_ADAP = 0x04,
> TB_PORT_CAP_VSE = 0x05,
> + TB_PORT_CAP_USB4 = 0x06,
> };
>
> enum tb_port_state {
> @@ -164,10 +165,36 @@ struct tb_regs_switch_header {
> * milliseconds. Writing 0x00 is interpreted
> * as 255ms.
> */
> - u32 __unknown4:16;
> + u32 cmuv:8;
> + u32 __unknown4:8;
> u32 thunderbolt_version:8;
> } __packed;
>
> +/* USB4 version 1.0 */
> +#define USB4_VERSION_1_0 0x20
> +
> +#define ROUTER_CS_1 0x01
> +#define ROUTER_CS_4 0x04
> +#define ROUTER_CS_5 0x05
> +#define ROUTER_CS_5_SLP BIT(0)
> +#define ROUTER_CS_5_C3S BIT(23)
> +#define ROUTER_CS_5_PTO BIT(24)
> +#define ROUTER_CS_5_HCO BIT(26)
> +#define ROUTER_CS_5_CV BIT(31)
> +#define ROUTER_CS_6 0x06
> +#define ROUTER_CS_6_SLPR BIT(0)
> +#define ROUTER_CS_6_TNS BIT(1)
> +#define ROUTER_CS_6_HCI BIT(18)
> +#define ROUTER_CS_6_CR BIT(25)
> +#define ROUTER_CS_7 0x07
> +#define ROUTER_CS_9 0x09
> +#define ROUTER_CS_25 0x19
> +#define ROUTER_CS_26 0x1a
> +#define ROUTER_CS_26_STATUS_MASK GENMASK(29, 24)
> +#define ROUTER_CS_26_STATUS_SHIFT 24
> +#define ROUTER_CS_26_ONS BIT(30)
> +#define ROUTER_CS_26_OV BIT(31)
> +
> enum tb_port_type {
> TB_TYPE_INACTIVE = 0x000000,
> TB_TYPE_PORT = 0x000001,
> @@ -216,6 +243,7 @@ struct tb_regs_port_header {
> #define ADP_CS_4_NFC_BUFFERS_MASK GENMASK(9, 0)
> #define ADP_CS_4_TOTAL_BUFFERS_MASK GENMASK(29, 20)
> #define ADP_CS_4_TOTAL_BUFFERS_SHIFT 20
> +#define ADP_CS_4_LCK BIT(31)
> #define ADP_CS_5 0x05
> #define ADP_CS_5_LCA_MASK GENMASK(28, 22)
> #define ADP_CS_5_LCA_SHIFT 22
> @@ -237,6 +265,12 @@ struct tb_regs_port_header {
> #define LANE_ADP_CS_1_CURRENT_WIDTH_MASK GENMASK(25, 20)
> #define LANE_ADP_CS_1_CURRENT_WIDTH_SHIFT 20
>
> +/* USB4 port registers */
> +#define PORT_CS_18 0x12
> +#define PORT_CS_18_BE BIT(8)
> +#define PORT_CS_19 0x13
> +#define PORT_CS_19_PC BIT(3)
> +
> /* Display Port adapter registers */
Nitpick: DisplayPort is a single word.

> #define ADP_DP_CS_0 0x00
> #define ADP_DP_CS_0_VIDEO_HOPID_MASK GENMASK(26, 16)
> diff --git a/drivers/thunderbolt/tunnel.c b/drivers/thunderbolt/tunnel.c
> index 0d3463c4e24a..21d266a76b7d 100644
> --- a/drivers/thunderbolt/tunnel.c
> +++ b/drivers/thunderbolt/tunnel.c
> @@ -243,6 +243,12 @@ struct tb_tunnel *tb_tunnel_alloc_pci(struct tb *tb, struct tb_port *up,
> return tunnel;
> }
>
> +static bool tb_dp_is_usb4(const struct tb_switch *sw)
> +{
> + /* Titan Ridge DP adapters need the same treatment as USB4 */
> + return tb_switch_is_usb4(sw) || tb_switch_is_titan_ridge(sw);
> +}
> +
> static int tb_dp_cm_handshake(struct tb_port *in, struct tb_port *out)
> {
> int timeout = 10;
> @@ -250,8 +256,7 @@ static int tb_dp_cm_handshake(struct tb_port *in, struct tb_port *out)
> int ret;
>
> /* Both ends need to support this */
> - if (!tb_switch_is_titan_ridge(in->sw) ||
> - !tb_switch_is_titan_ridge(out->sw))
> + if (!tb_dp_is_usb4(in->sw) || !tb_dp_is_usb4(out->sw))
> return 0;
>
> ret = tb_port_read(out, &val, TB_CFG_PORT,
> @@ -531,7 +536,7 @@ static int tb_dp_consumed_bandwidth(struct tb_tunnel *tunnel)
> u32 val, rate = 0, lanes = 0;
> int ret;
>
> - if (tb_switch_is_titan_ridge(sw)) {
> + if (tb_dp_is_usb4(sw)) {
> int timeout = 10;
>
> /*
> diff --git a/drivers/thunderbolt/usb4.c b/drivers/thunderbolt/usb4.c
> new file mode 100644
> index 000000000000..b84c74346d2b
> --- /dev/null
> +++ b/drivers/thunderbolt/usb4.c
> @@ -0,0 +1,724 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * USB4 specific functionality
> + *
> + * Copyright (C) 2019, Intel Corporation
> + * Authors: Mika Westerberg <mika.westerberg@xxxxxxxxxxxxxxx>
> + * Rajmohan Mani <rajmohan.mani@xxxxxxxxx>
> + */
> +
> +#include <linux/delay.h>
> +#include <linux/ktime.h>
> +
> +#include "tb.h"
> +
> +#define USB4_DATA_DWORDS 16
> +#define USB4_DATA_RETRIES 3
> +
> +enum usb4_switch_op {
> + USB4_SWITCH_OP_QUERY_DP_RESOURCE = 0x10,
> + USB4_SWITCH_OP_ALLOC_DP_RESOURCE = 0x11,
> + USB4_SWITCH_OP_DEALLOC_DP_RESOURCE = 0x12,
> + USB4_SWITCH_OP_NVM_WRITE = 0x20,
> + USB4_SWITCH_OP_NVM_AUTH = 0x21,
> + USB4_SWITCH_OP_NVM_READ = 0x22,
> + USB4_SWITCH_OP_NVM_SET_OFFSET = 0x23,
> + USB4_SWITCH_OP_DROM_READ = 0x24,
> + USB4_SWITCH_OP_NVM_SECTOR_SIZE = 0x25,
> +};
> +
> +#define USB4_NVM_READ_OFFSET_MASK GENMASK(23, 2)
> +#define USB4_NVM_READ_OFFSET_SHIFT 2
> +#define USB4_NVM_READ_LENGTH_MASK GENMASK(27, 24)
> +#define USB4_NVM_READ_LENGTH_SHIFT 24
> +
> +#define USB4_NVM_SET_OFFSET_MASK USB4_NVM_READ_OFFSET_MASK
> +#define USB4_NVM_SET_OFFSET_SHIFT USB4_NVM_READ_OFFSET_SHIFT
> +
> +#define USB4_DROM_ADDRESS_MASK GENMASK(14, 2)
> +#define USB4_DROM_ADDRESS_SHIFT 2
> +#define USB4_DROM_SIZE_MASK GENMASK(19, 15)
> +#define USB4_DROM_SIZE_SHIFT 15
> +
> +#define USB4_NVM_SECTOR_SIZE_MASK GENMASK(23, 0)
> +
> +typedef int (*read_block_fn)(struct tb_switch *, unsigned int, void *, size_t);
> +typedef int (*write_block_fn)(struct tb_switch *, const void *, size_t);
> +
> +static int usb4_switch_wait_for_bit(struct tb_switch *sw, u32 offset, u32 bit,
> + u32 value, int timeout_msec)
> +{
> + ktime_t timeout = ktime_add_ms(ktime_get(), timeout_msec);
> +
> + do {
> + u32 val;
> + int ret;
> +
> + ret = tb_sw_read(sw, &val, TB_CFG_SWITCH, offset, 1);
> + if (ret)
> + return ret;
> +
> + if ((val & bit) == value)
> + return 0;
> +
> + usleep_range(50, 100);
> + } while (ktime_before(ktime_get(), timeout));
> +
> + return -ETIMEDOUT;
> +}
> +
> +static int usb4_switch_op_read_data(struct tb_switch *sw, void *data,
> + size_t dwords)
> +{
> + if (dwords > USB4_DATA_DWORDS)
> + return -EINVAL;
> +
> + return tb_sw_read(sw, data, TB_CFG_SWITCH, ROUTER_CS_9, dwords);
> +}
> +
> +static int usb4_switch_op_write_data(struct tb_switch *sw, const void *data,
> + size_t dwords)
> +{
> + if (dwords > USB4_DATA_DWORDS)
> + return -EINVAL;
> +
> + return tb_sw_write(sw, data, TB_CFG_SWITCH, ROUTER_CS_9, dwords);
> +}
> +
> +static int usb4_switch_op_read_metadata(struct tb_switch *sw, u32 *metadata)
> +{
> + return tb_sw_read(sw, metadata, TB_CFG_SWITCH, ROUTER_CS_25, 1);
> +}
> +
> +static int usb4_switch_op_write_metadata(struct tb_switch *sw, u32 metadata)
> +{
> + return tb_sw_write(sw, &metadata, TB_CFG_SWITCH, ROUTER_CS_25, 1);
> +}
> +
> +static int usb4_switch_do_read_data(struct tb_switch *sw, u16 address,
> + void *buf, size_t size, read_block_fn read_block)
> +{
> + unsigned int retries = USB4_DATA_RETRIES;
> + unsigned int offset;
> +
> + offset = address & 3;
> + address = address & ~3;
> +
> + do {
> + size_t nbytes = min_t(size_t, size, USB4_DATA_DWORDS * 4);
> + unsigned int dwaddress, dwords;
> + u8 data[USB4_DATA_DWORDS * 4];
> + int ret;
> +
> + dwaddress = address / 4;
> + dwords = ALIGN(nbytes, 4) / 4;
> +
> + ret = read_block(sw, dwaddress, data, dwords);
> + if (ret) {
> + if (ret == -ETIMEDOUT) {
> + if (retries--)
> + continue;
> + ret = -EIO;
> + }
> + return ret;
> + }
> +
> + memcpy(buf, data + offset, nbytes);
> +
> + size -= nbytes;
> + address += nbytes;
> + buf += nbytes;
> + } while (size > 0);
> +
> + return 0;
> +}
> +
> +static int usb4_switch_do_write_data(struct tb_switch *sw, u16 address,
> + const void *buf, size_t size, write_block_fn write_next_block)
> +{
> + unsigned int retries = USB4_DATA_RETRIES;
> + unsigned int offset;
> +
> + offset = address & 3;
> + address = address & ~3;
> +
> + do {
> + u32 nbytes = min_t(u32, size, USB4_DATA_DWORDS * 4);
> + u8 data[USB4_DATA_DWORDS * 4];
> + int ret;
> +
> + memcpy(data + offset, buf, nbytes);
> +
> + ret = write_next_block(sw, data, nbytes / 4);
> + if (ret) {
> + if (ret == -ETIMEDOUT) {
> + if (retries--)
> + continue;
> + ret = -EIO;
> + }
> + return ret;
> + }
> +
> + size -= nbytes;
> + address += nbytes;
> + buf += nbytes;
> + } while (size > 0);
> +
> + return 0;
> +}
> +
> +static int usb4_switch_op(struct tb_switch *sw, u16 opcode, u8 *status)
> +{
> + u32 val;
> + int ret;
> +
> + val = opcode | ROUTER_CS_26_OV;
> + ret = tb_sw_write(sw, &val, TB_CFG_SWITCH, ROUTER_CS_26, 1);
> + if (ret)
> + return ret;
> +
> + ret = usb4_switch_wait_for_bit(sw, ROUTER_CS_26, ROUTER_CS_26_OV, 0, 500);
> + if (ret)
> + return ret;
> +
> + ret = tb_sw_read(sw, &val, TB_CFG_SWITCH, ROUTER_CS_26, 1);
> + if (val & ROUTER_CS_26_ONS)
> + return -EOPNOTSUPP;
> +
> + *status = (val & ROUTER_CS_26_STATUS_MASK) >> ROUTER_CS_26_STATUS_SHIFT;
> + return 0;
> +}
> +
> +/**
> + * usb4_switch_setup() - Additional setup for USB4 device
> + * @sw: USB4 router to setup
> + *
> + * USB4 routers need additional settings in order to enable all the
> + * tunneling. This function enables USB and PCIe tunneling if it can be
> + * enabled (e.g the parent switch also supports them). If USB tunneling
> + * is not available for some reason (like that there is Thunderbolt 3
> + * switch upstream) then the internal xHCI controller is enabled
> + * instead.
> + */
> +int usb4_switch_setup(struct tb_switch *sw)
> +{
> + struct tb_switch *parent;
> + bool tbt3, xhci;
> + u32 val = 0;
> + int ret;
> +
> + if (!tb_route(sw))
> + return 0;
> +
> + ret = tb_sw_read(sw, &val, TB_CFG_SWITCH, ROUTER_CS_6, 1);
> + if (ret)
> + return ret;
> +
> + xhci = val & ROUTER_CS_6_HCI;
> + tbt3 = !(val & ROUTER_CS_6_TNS);
> +
> + tb_sw_dbg(sw, "TBT3 support: %s, xHCI: %s\n",
> + tbt3 ? "yes" : "no", xhci ? "yes" : "no");
> +
> + ret = tb_sw_read(sw, &val, TB_CFG_SWITCH, ROUTER_CS_5, 1);
> + if (ret)
> + return ret;
> +
> + parent = tb_switch_parent(sw);
> +
> + /* Only enable PCIe tunneling if the parent router supports it */
> + if (tb_switch_find_port(parent, TB_TYPE_PCIE_DOWN)) {
> + val |= ROUTER_CS_5_PTO;
> + /* xHCI can be enabled if PCIe tunneling is supported */
> + if (xhci & ROUTER_CS_6_HCI)
> + val |= ROUTER_CS_5_HCO;
> + }
> +
> + /* TBT3 supported by the CM */
> + val |= ROUTER_CS_5_C3S;
> + /* Tunneling configuration is ready now */
> + val |= ROUTER_CS_5_CV;
> +
> + ret = tb_sw_write(sw, &val, TB_CFG_SWITCH, ROUTER_CS_5, 1);
> + if (ret)
> + return ret;
> +
> + return usb4_switch_wait_for_bit(sw, ROUTER_CS_6, ROUTER_CS_6_CR,
> + ROUTER_CS_6_CR, 50);
> +}
> +
> +/**
> + * usb4_switch_read_uid() - Read UID from USB4 router
> + * @sw: USB4 router
> + *
> + * Reads 64-bit UID from USB4 router config space.
> + */
> +int usb4_switch_read_uid(struct tb_switch *sw, u64 *uid)
> +{
> + return tb_sw_read(sw, uid, TB_CFG_SWITCH, ROUTER_CS_7, 2);
> +}
> +
> +static int usb4_switch_drom_read_block(struct tb_switch *sw,
> + unsigned int dwaddress, void *buf,
> + size_t dwords)
> +{
> + u8 status = 0;
> + u32 metadata;
> + int ret;
> +
> + metadata = (dwords << USB4_DROM_SIZE_SHIFT) & USB4_DROM_SIZE_MASK;
> + metadata |= (dwaddress << USB4_DROM_ADDRESS_SHIFT) &
> + USB4_DROM_ADDRESS_MASK;
> +
> + ret = usb4_switch_op_write_metadata(sw, metadata);
> + if (ret)
> + return ret;
> +
> + ret = usb4_switch_op(sw, USB4_SWITCH_OP_DROM_READ, &status);
> + if (ret)
> + return ret;
> +
> + if (status)
> + return -EIO;
> +
> + return usb4_switch_op_read_data(sw, buf, dwords);
> +}
> +
> +/**
> + * usb4_switch_drom_read() - Read arbitrary bytes from USB4 router DROM
> + * @sw: USB4 router
> + *
> + * Uses USB4 router operations to read router DROM. For devices this
> + * should always work but for hosts it may return %-EOPNOTSUPP in which
> + * case the host router does not have DROM.
> + */
> +int usb4_switch_drom_read(struct tb_switch *sw, unsigned int address, void *buf,
> + size_t size)
> +{
> + return usb4_switch_do_read_data(sw, address, buf, size,
> + usb4_switch_drom_read_block);
> +}
> +
> +static int usb4_set_port_configured(struct tb_port *port, bool configured)
> +{
> + int ret;
> + u32 val;
> +
> + ret = tb_port_read(port, &val, TB_CFG_PORT,
> + port->cap_usb4 + PORT_CS_19, 1);
> + if (ret)
> + return ret;
> +
> + if (configured)
> + val |= PORT_CS_19_PC;
> + else
> + val &= ~PORT_CS_19_PC;
> +
> + return tb_port_write(port, &val, TB_CFG_PORT,
> + port->cap_usb4 + PORT_CS_19, 1);
> +}
> +
> +/**
> + * usb4_switch_configure_link() - Set upstream USB4 link configured
> + * @sw: USB4 router
> + *
> + * Sets the upstream USB4 link to be configured for power management
> + * purposes.
> + */
> +int usb4_switch_configure_link(struct tb_switch *sw)
> +{
> + struct tb_port *up;
> +
> + if (!tb_route(sw))
> + return 0;
> +
> + up = tb_upstream_port(sw);
> + return usb4_set_port_configured(up, true);
> +}
> +
> +/**
> + * usb4_switch_unconfigure_link() - Un-set upstream USB4 link configuration
> + * @sw: USB4 router
> + *
> + * Reverse of usb4_switch_configure_link().
> + */
> +void usb4_switch_unconfigure_link(struct tb_switch *sw)
> +{
> + struct tb_port *up;
> +
> + if (sw->is_unplugged || !tb_route(sw))
> + return;
> +
> + up = tb_upstream_port(sw);
> + usb4_set_port_configured(up, false);
> +}
> +
> +/**
> + * usb4_switch_lane_bonding_possible() - Are conditions met for lane bonding
> + * @sw: USB4 router
> + *
> + * Checks whether conditions are met so that lane bonding can be
> + * established with the upstream router. Call only for device routers.
> + */
> +bool usb4_switch_lane_bonding_possible(struct tb_switch *sw)
> +{
> + struct tb_port *up;
> + int ret;
> + u32 val;
> +
> + up = tb_upstream_port(sw);
> + ret = tb_port_read(up, &val, TB_CFG_PORT, up->cap_usb4 + PORT_CS_18, 1);
> + if (ret)
> + return false;
> +
> + return !!(val & PORT_CS_18_BE);
> +}
> +
> +/**
> + * usb4_switch_set_sleep() - Prepare the router to enter sleep
> + * @sw: USB4 router
> + *
> + * Enables wakes and sets sleep bit for the router. Returns when the
> + * router sleep ready bit has been asserted.
> + */
> +int usb4_switch_set_sleep(struct tb_switch *sw)
> +{
> + int ret;
> + u32 val;
> +
> + /* Set sleep bit and wait for sleep ready to be asserted */
> + ret = tb_sw_read(sw, &val, TB_CFG_SWITCH, ROUTER_CS_5, 1);
> + if (ret)
> + return ret;
> +
> + val |= ROUTER_CS_5_SLP;
> +
> + ret = tb_sw_write(sw, &val, TB_CFG_SWITCH, ROUTER_CS_5, 1);
> + if (ret)
> + return ret;
> +
> + return usb4_switch_wait_for_bit(sw, ROUTER_CS_6, ROUTER_CS_6_SLPR,
> + ROUTER_CS_6_SLPR, 500);
> +}
> +
> +/**
> + * usb4_switch_nvm_sector_size() - Return router NVM sector size
> + * @sw: USB4 router
> + *
> + * If the router supports NVM operations this function returns the NVM
> + * sector size in bytes. If NVM operations are not supported returns
> + * %-EOPNOTSUPP.
> + */
> +int usb4_switch_nvm_sector_size(struct tb_switch *sw)
> +{
> + u32 metadata;
> + u8 status;
> + int ret;
> +
> + ret = usb4_switch_op(sw, USB4_SWITCH_OP_NVM_SECTOR_SIZE, &status);
> + if (ret)
> + return ret;
> +
> + if (status)
> + return status == 0x2 ? -EOPNOTSUPP : -EIO;
> +
> + ret = usb4_switch_op_read_metadata(sw, &metadata);
> + if (ret)
> + return ret;
> +
> + return metadata & USB4_NVM_SECTOR_SIZE_MASK;
> +}
> +
> +static int usb4_switch_nvm_read_block(struct tb_switch *sw,
> + unsigned int dwaddress, void *buf, size_t dwords)
> +{
> + u8 status = 0;
> + u32 metadata;
> + int ret;
> +
> + metadata = (dwords << USB4_NVM_READ_LENGTH_SHIFT) &
> + USB4_NVM_READ_LENGTH_MASK;
> + metadata |= (dwaddress << USB4_NVM_READ_OFFSET_SHIFT) &
> + USB4_NVM_READ_OFFSET_MASK;
> +
> + ret = usb4_switch_op_write_metadata(sw, metadata);
> + if (ret)
> + return ret;
> +
> + ret = usb4_switch_op(sw, USB4_SWITCH_OP_NVM_READ, &status);
> + if (ret)
> + return ret;
> +
> + if (status)
> + return -EIO;
> +
> + return usb4_switch_op_read_data(sw, buf, dwords);
> +}
> +
> +/**
> + * usb4_switch_nvm_read() - Read arbitrary bytes from router NVM
> + * @sw: USB4 router
> + * @address: Starting address in bytes
> + * @buf: Read data is placed here
> + * @size: How many bytes to read
> + *
> + * Reads NVM contents of the router. If NVM is not supported returns
> + * %-EOPNOTSUPP.
> + */
> +int usb4_switch_nvm_read(struct tb_switch *sw, unsigned int address, void *buf,
> + size_t size)
> +{
> + return usb4_switch_do_read_data(sw, address, buf, size,
> + usb4_switch_nvm_read_block);
> +}
> +
> +static int usb4_switch_nvm_set_offset(struct tb_switch *sw,
> + unsigned int address)
> +{
> + u32 metadata, dwaddress;
> + u8 status = 0;
> + int ret;
> +
> + dwaddress = address / 4;
> + metadata = (dwaddress << USB4_NVM_SET_OFFSET_SHIFT) &
> + USB4_NVM_SET_OFFSET_MASK;
> +
> + ret = usb4_switch_op_write_metadata(sw, metadata);
> + if (ret)
> + return ret;
> +
> + ret = usb4_switch_op(sw, USB4_SWITCH_OP_NVM_SET_OFFSET, &status);
> + if (ret)
> + return ret;
> +
> + return status ? -EIO : 0;
> +}
> +
> +static int usb4_switch_nvm_write_next_block(struct tb_switch *sw,
> + const void *buf, size_t dwords)
> +{
> + u8 status;
> + int ret;
> +
> + ret = usb4_switch_op_write_data(sw, buf, dwords);
> + if (ret)
> + return ret;
> +
> + ret = usb4_switch_op(sw, USB4_SWITCH_OP_NVM_WRITE, &status);
> + if (ret)
> + return ret;
> +
> + return status ? -EIO : 0;
> +}
> +
> +/**
> + * usb4_switch_nvm_write() - Write to the router NVM
> + * @sw: USB4 router
> + * @address: Start address where to write in bytes
> + * @buf: Pointer to the data to write
> + * @size: Size of @buf in bytes
> + *
> + * Writes @buf to the router NVM using USB4 router operations. If NVM
> + * write is not supported returns %-EOPNOTSUPP.
> + */
> +int usb4_switch_nvm_write(struct tb_switch *sw, unsigned int address,
> + const void *buf, size_t size)
> +{
> + int ret;
> +
> + ret = usb4_switch_nvm_set_offset(sw, address);
> + if (ret)
> + return ret;
> +
> + return usb4_switch_do_write_data(sw, address, buf, size,
> + usb4_switch_nvm_write_next_block);
> +}
> +
> +/**
> + * usb4_switch_nvm_authenticate() - Authenticate new NVM
> + * @sw: USB4 router
> + *
> + * After the new NVM has been written via usb4_switch_nvm_write(), this
> + * function triggers NVM authentication process. If the authentication
> + * is successful the router is power cycled and the new NVM starts
> + * running. In case of failure returns negative errno.
> + */
> +int usb4_switch_nvm_authenticate(struct tb_switch *sw)
> +{
> + u8 status = 0;
> + int ret;
> +
> + ret = usb4_switch_op(sw, USB4_SWITCH_OP_NVM_AUTH, &status);
> + if (ret)
> + return ret;
> +
> + switch (status) {
> + case 0x0:
> + tb_sw_dbg(sw, "NVM authentication successful\n");
> + return 0;
> + case 0x1:
> + return -EINVAL;
> + case 0x2:
> + return -EAGAIN;
> + case 0x3:
> + return -EOPNOTSUPP;
> + default:
> + return -EIO;
> + }
> +}
> +
> +/**
> + * usb4_switch_query_dp_resource() - Query availability of DP IN resource
> + * @sw: USB4 router
> + * @in: DP IN adapter
> + *
> + * For DP tunneling this function can be used to query availability of
> + * DP IN resource. Returns true if the resource is available for DP
> + * tunneling, false otherwise.
> + */
> +bool usb4_switch_query_dp_resource(struct tb_switch *sw, struct tb_port *in)
> +{
> + u8 status;
> + int ret;
> +
> + ret = usb4_switch_op_write_metadata(sw, in->port);
> + if (ret)
> + return false;
> +
> + ret = usb4_switch_op(sw, USB4_SWITCH_OP_QUERY_DP_RESOURCE, &status);
> + /*
> + * If DP resource allocation is not supported assume it is
> + * always available.
> + */
> + if (ret == -EOPNOTSUPP)
> + return true;
> + else if (ret)
> + return false;
> +
> + return !status;
> +}
> +
> +/**
> + * usb4_switch_alloc_dp_resource() - Allocate DP IN resource
> + * @sw: USB4 router
> + * @in: DP IN adapter
> + *
> + * Allocates DP IN resource for DP tunneling using USB4 router
> + * operations. If the resource was allocated returns %0. Otherwise
> + * returns negative errno, in particular %-EBUSY if the resource is
> + * already allocated.
> + */
> +int usb4_switch_alloc_dp_resource(struct tb_switch *sw, struct tb_port *in)
> +{
> + u8 status;
> + int ret;
> +
> + ret = usb4_switch_op_write_metadata(sw, in->port);
> + if (ret)
> + return ret;
> +
> + ret = usb4_switch_op(sw, USB4_SWITCH_OP_ALLOC_DP_RESOURCE, &status);
> + if (ret == -EOPNOTSUPP)
> + return 0;
> + else if (ret)
> + return ret;
> +
> + return status ? -EBUSY : 0;
> +}
> +
> +/**
> + * usb4_switch_dealloc_dp_resource() - Releases allocated DP IN resource
> + * @sw: USB4 router
> + * @in: DP IN adapter
> + *
> + * Releases the previously allocated DP IN resource.
> + */
> +int usb4_switch_dealloc_dp_resource(struct tb_switch *sw, struct tb_port *in)
> +{
> + u8 status;
> + int ret;
> +
> + ret = usb4_switch_op_write_metadata(sw, in->port);
> + if (ret)
> + return ret;
> +
> + ret = usb4_switch_op(sw, USB4_SWITCH_OP_DEALLOC_DP_RESOURCE, &status);
> + if (ret == -EOPNOTSUPP)
> + return 0;
> + else if (ret)
> + return ret;
> +
> + return status ? -EIO : 0;
> +}
> +
> +static int usb4_port_idx(const struct tb_switch *sw, const struct tb_port *port)
> +{
> + struct tb_port *p;
> + int usb4_idx = 0;
> +
> + /* Assume port is primary */
> + tb_switch_for_each_port(sw, p) {
> + if (!tb_port_is_null(p))
> + continue;
> + if (tb_is_upstream_port(p))
> + continue;
> + if (!p->link_nr) {
> + if (p == port)
> + break;
> + usb4_idx++;
> + }
> + }
> +
> + return usb4_idx;
> +}
> +
> +/**
> + * usb4_switch_map_pcie_down() - Map USB4 port to a PCIe downstream adapter
> + * @sw: USB4 router
> + * @port: USB4 port
> + *
> + * USB4 routers have direct mapping between USB4 ports and PCIe
> + * downstream adapters where the PCIe topology is extended. This
> + * function returns the corresponding downstream PCIe adapter or %NULL
> + * if no such mapping was possible.
> + */
> +struct tb_port *usb4_switch_map_pcie_down(struct tb_switch *sw,
> + const struct tb_port *port)
> +{
> + int usb4_idx = usb4_port_idx(sw, port);
> + struct tb_port *p;
> + int pcie_idx = 0;
> +
> + /* Find PCIe down port matching usb4_port */
> + tb_switch_for_each_port(sw, p) {
> + if (!tb_port_is_pcie_down(p))
> + continue;
> +
> + if (pcie_idx == usb4_idx && !tb_pci_port_is_enabled(p))
> + return p;
> +
> + pcie_idx++;
> + }
> +
> + return NULL;
> +}
> +
> +/**
> + * usb4_port_unlock() - Unlock USB4 downstream port
> + * @port: USB4 port to unlock
> + *
> + * Unlocks USB4 downstream port so that the connection manager can
> + * access the router below this port.
> + */
> +int usb4_port_unlock(struct tb_port *port)
> +{
> + int ret;
> + u32 val;
> +
> + ret = tb_port_read(port, &val, TB_CFG_PORT, ADP_CS_4, 1);
> + if (ret)
> + return ret;
> +
> + val &= ~ADP_CS_4_LCK;
> + return tb_port_write(port, &val, TB_CFG_PORT, ADP_CS_4, 1);
> +}
> diff --git a/drivers/thunderbolt/xdomain.c b/drivers/thunderbolt/xdomain.c
> index 880d784398a3..053f918e00e8 100644
> --- a/drivers/thunderbolt/xdomain.c
> +++ b/drivers/thunderbolt/xdomain.c
> @@ -1220,7 +1220,13 @@ struct tb_xdomain *tb_xdomain_alloc(struct tb *tb, struct device *parent,
> u64 route, const uuid_t *local_uuid,
> const uuid_t *remote_uuid)
> {
> + struct tb_switch *parent_sw = tb_to_switch(parent);
> struct tb_xdomain *xd;
> + struct tb_port *down;
> +
> + /* Make sure the downstream domain is accessible */
> + down = tb_port_at(route, parent_sw);
> + tb_port_unlock(down);
>
> xd = kzalloc(sizeof(*xd), GFP_KERNEL);
> if (!xd)
> --
> 2.24.0
>

Kind regards,
Nicholas