diff options
Diffstat (limited to 'drivers/thunderbolt/acpi.c')
| -rw-r--r-- | drivers/thunderbolt/acpi.c | 386 |
1 files changed, 386 insertions, 0 deletions
diff --git a/drivers/thunderbolt/acpi.c b/drivers/thunderbolt/acpi.c new file mode 100644 index 000000000..7a8adf5ad --- /dev/null +++ b/drivers/thunderbolt/acpi.c @@ -0,0 +1,386 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * ACPI support + * + * Copyright (C) 2020, Intel Corporation + * Author: Mika Westerberg <mika.westerberg@linux.intel.com> + */ + +#include <linux/acpi.h> +#include <linux/pm_runtime.h> + +#include "tb.h" + +static acpi_status tb_acpi_add_link(acpi_handle handle, u32 level, void *data, + void **return_value) +{ + struct acpi_device *adev = acpi_fetch_acpi_dev(handle); + struct fwnode_reference_args args; + struct fwnode_handle *fwnode; + struct tb_nhi *nhi = data; + struct pci_dev *pdev; + struct device *dev; + int ret; + + if (!adev) + return AE_OK; + + fwnode = acpi_fwnode_handle(adev); + ret = fwnode_property_get_reference_args(fwnode, "usb4-host-interface", + NULL, 0, 0, &args); + if (ret) + return AE_OK; + + /* It needs to reference this NHI */ + if (dev_fwnode(&nhi->pdev->dev) != args.fwnode) + goto out_put; + + /* + * Try to find physical device walking upwards to the hierarcy. + * We need to do this because the xHCI driver might not yet be + * bound so the USB3 SuperSpeed ports are not yet created. + */ + dev = acpi_get_first_physical_node(adev); + while (!dev) { + adev = acpi_dev_parent(adev); + if (!adev) + break; + dev = acpi_get_first_physical_node(adev); + } + + if (!dev) + goto out_put; + + /* + * Check that the device is PCIe. This is because USB3 + * SuperSpeed ports have this property and they are not power + * managed with the xHCI and the SuperSpeed hub so we create the + * link from xHCI instead. + */ + while (dev && !dev_is_pci(dev)) + dev = dev->parent; + + if (!dev) + goto out_put; + + /* + * Check that this actually matches the type of device we + * expect. It should either be xHCI or PCIe root/downstream + * port. + */ + pdev = to_pci_dev(dev); + if (pdev->class == PCI_CLASS_SERIAL_USB_XHCI || + (pci_is_pcie(pdev) && + (pci_pcie_type(pdev) == PCI_EXP_TYPE_ROOT_PORT || + pci_pcie_type(pdev) == PCI_EXP_TYPE_DOWNSTREAM))) { + const struct device_link *link; + + /* + * Make them both active first to make sure the NHI does + * not runtime suspend before the consumer. The + * pm_runtime_put() below then allows the consumer to + * runtime suspend again (which then allows NHI runtime + * suspend too now that the device link is established). + */ + pm_runtime_get_sync(&pdev->dev); + + link = device_link_add(&pdev->dev, &nhi->pdev->dev, + DL_FLAG_AUTOREMOVE_SUPPLIER | + DL_FLAG_RPM_ACTIVE | + DL_FLAG_PM_RUNTIME); + if (link) { + dev_dbg(&nhi->pdev->dev, "created link from %s\n", + dev_name(&pdev->dev)); + } else { + dev_warn(&nhi->pdev->dev, "device link creation from %s failed\n", + dev_name(&pdev->dev)); + } + + pm_runtime_put(&pdev->dev); + } + +out_put: + fwnode_handle_put(args.fwnode); + return AE_OK; +} + +/** + * tb_acpi_add_links() - Add device links based on ACPI description + * @nhi: Pointer to NHI + * + * Goes over ACPI namespace finding tunneled ports that reference to + * @nhi ACPI node. For each reference a device link is added. The link + * is automatically removed by the driver core. + */ +void tb_acpi_add_links(struct tb_nhi *nhi) +{ + acpi_status status; + + if (!has_acpi_companion(&nhi->pdev->dev)) + return; + + /* + * Find all devices that have usb4-host-controller interface + * property that references to this NHI. + */ + status = acpi_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT, 32, + tb_acpi_add_link, NULL, nhi, NULL); + if (ACPI_FAILURE(status)) + dev_warn(&nhi->pdev->dev, "failed to enumerate tunneled ports\n"); +} + +/** + * tb_acpi_is_native() - Did the platform grant native TBT/USB4 control + * + * Returns %true if the platform granted OS native control over + * TBT/USB4. In this case software based connection manager can be used, + * otherwise there is firmware based connection manager running. + */ +bool tb_acpi_is_native(void) +{ + return osc_sb_native_usb4_support_confirmed && + osc_sb_native_usb4_control; +} + +/** + * tb_acpi_may_tunnel_usb3() - Is USB3 tunneling allowed by the platform + * + * When software based connection manager is used, this function + * returns %true if platform allows native USB3 tunneling. + */ +bool tb_acpi_may_tunnel_usb3(void) +{ + if (tb_acpi_is_native()) + return osc_sb_native_usb4_control & OSC_USB_USB3_TUNNELING; + return true; +} + +/** + * tb_acpi_may_tunnel_dp() - Is DisplayPort tunneling allowed by the platform + * + * When software based connection manager is used, this function + * returns %true if platform allows native DP tunneling. + */ +bool tb_acpi_may_tunnel_dp(void) +{ + if (tb_acpi_is_native()) + return osc_sb_native_usb4_control & OSC_USB_DP_TUNNELING; + return true; +} + +/** + * tb_acpi_may_tunnel_pcie() - Is PCIe tunneling allowed by the platform + * + * When software based connection manager is used, this function + * returns %true if platform allows native PCIe tunneling. + */ +bool tb_acpi_may_tunnel_pcie(void) +{ + if (tb_acpi_is_native()) + return osc_sb_native_usb4_control & OSC_USB_PCIE_TUNNELING; + return true; +} + +/** + * tb_acpi_is_xdomain_allowed() - Are XDomain connections allowed + * + * When software based connection manager is used, this function + * returns %true if platform allows XDomain connections. + */ +bool tb_acpi_is_xdomain_allowed(void) +{ + if (tb_acpi_is_native()) + return osc_sb_native_usb4_control & OSC_USB_XDOMAIN; + return true; +} + +/* UUID for retimer _DSM: e0053122-795b-4122-8a5e-57be1d26acb3 */ +static const guid_t retimer_dsm_guid = + GUID_INIT(0xe0053122, 0x795b, 0x4122, + 0x8a, 0x5e, 0x57, 0xbe, 0x1d, 0x26, 0xac, 0xb3); + +#define RETIMER_DSM_QUERY_ONLINE_STATE 1 +#define RETIMER_DSM_SET_ONLINE_STATE 2 + +static int tb_acpi_retimer_set_power(struct tb_port *port, bool power) +{ + struct usb4_port *usb4 = port->usb4; + union acpi_object argv4[2]; + struct acpi_device *adev; + union acpi_object *obj; + int ret; + + if (!usb4->can_offline) + return 0; + + adev = ACPI_COMPANION(&usb4->dev); + if (WARN_ON(!adev)) + return 0; + + /* Check if we are already powered on (and in correct mode) */ + obj = acpi_evaluate_dsm_typed(adev->handle, &retimer_dsm_guid, 1, + RETIMER_DSM_QUERY_ONLINE_STATE, NULL, + ACPI_TYPE_INTEGER); + if (!obj) { + tb_port_warn(port, "ACPI: query online _DSM failed\n"); + return -EIO; + } + + ret = obj->integer.value; + ACPI_FREE(obj); + + if (power == ret) + return 0; + + tb_port_dbg(port, "ACPI: calling _DSM to power %s retimers\n", + power ? "on" : "off"); + + argv4[0].type = ACPI_TYPE_PACKAGE; + argv4[0].package.count = 1; + argv4[0].package.elements = &argv4[1]; + argv4[1].integer.type = ACPI_TYPE_INTEGER; + argv4[1].integer.value = power; + + obj = acpi_evaluate_dsm_typed(adev->handle, &retimer_dsm_guid, 1, + RETIMER_DSM_SET_ONLINE_STATE, argv4, + ACPI_TYPE_INTEGER); + if (!obj) { + tb_port_warn(port, + "ACPI: set online state _DSM evaluation failed\n"); + return -EIO; + } + + ret = obj->integer.value; + ACPI_FREE(obj); + + if (ret >= 0) { + if (power) + return ret == 1 ? 0 : -EBUSY; + return 0; + } + + tb_port_warn(port, "ACPI: set online state _DSM failed with error %d\n", ret); + return -EIO; +} + +/** + * tb_acpi_power_on_retimers() - Call platform to power on retimers + * @port: USB4 port + * + * Calls platform to turn on power to all retimers behind this USB4 + * port. After this function returns successfully the caller can + * continue with the normal retimer flows (as specified in the USB4 + * spec). Note if this returns %-EBUSY it means the type-C port is in + * non-USB4/TBT mode (there is non-USB4/TBT device connected). + * + * This should only be called if the USB4/TBT link is not up. + * + * Returns %0 on success. + */ +int tb_acpi_power_on_retimers(struct tb_port *port) +{ + return tb_acpi_retimer_set_power(port, true); +} + +/** + * tb_acpi_power_off_retimers() - Call platform to power off retimers + * @port: USB4 port + * + * This is the opposite of tb_acpi_power_on_retimers(). After returning + * successfully the normal operations with the @port can continue. + * + * Returns %0 on success. + */ +int tb_acpi_power_off_retimers(struct tb_port *port) +{ + return tb_acpi_retimer_set_power(port, false); +} + +static bool tb_acpi_bus_match(struct device *dev) +{ + return tb_is_switch(dev) || tb_is_usb4_port_device(dev); +} + +static struct acpi_device *tb_acpi_switch_find_companion(struct tb_switch *sw) +{ + struct acpi_device *adev = NULL; + struct tb_switch *parent_sw; + + /* + * Device routers exists under the downstream facing USB4 port + * of the parent router. Their _ADR is always 0. + */ + parent_sw = tb_switch_parent(sw); + if (parent_sw) { + struct tb_port *port = tb_port_at(tb_route(sw), parent_sw); + struct acpi_device *port_adev; + + port_adev = acpi_find_child_by_adr(ACPI_COMPANION(&parent_sw->dev), + port->port); + if (port_adev) + adev = acpi_find_child_device(port_adev, 0, false); + } else { + struct tb_nhi *nhi = sw->tb->nhi; + struct acpi_device *parent_adev; + + parent_adev = ACPI_COMPANION(&nhi->pdev->dev); + if (parent_adev) + adev = acpi_find_child_device(parent_adev, 0, false); + } + + return adev; +} + +static struct acpi_device *tb_acpi_find_companion(struct device *dev) +{ + /* + * The Thunderbolt/USB4 hierarchy looks like following: + * + * Device (NHI) + * Device (HR) // Host router _ADR == 0 + * Device (DFP0) // Downstream port _ADR == lane 0 adapter + * Device (DR) // Device router _ADR == 0 + * Device (UFP) // Upstream port _ADR == lane 0 adapter + * Device (DFP1) // Downstream port _ADR == lane 0 adapter number + * + * At the moment we bind the host router to the corresponding + * Linux device. + */ + if (tb_is_switch(dev)) + return tb_acpi_switch_find_companion(tb_to_switch(dev)); + else if (tb_is_usb4_port_device(dev)) + return acpi_find_child_by_adr(ACPI_COMPANION(dev->parent), + tb_to_usb4_port_device(dev)->port->port); + return NULL; +} + +static void tb_acpi_setup(struct device *dev) +{ + struct acpi_device *adev = ACPI_COMPANION(dev); + struct usb4_port *usb4 = tb_to_usb4_port_device(dev); + + if (!adev || !usb4) + return; + + if (acpi_check_dsm(adev->handle, &retimer_dsm_guid, 1, + BIT(RETIMER_DSM_QUERY_ONLINE_STATE) | + BIT(RETIMER_DSM_SET_ONLINE_STATE))) + usb4->can_offline = true; +} + +static struct acpi_bus_type tb_acpi_bus = { + .name = "thunderbolt", + .match = tb_acpi_bus_match, + .find_companion = tb_acpi_find_companion, + .setup = tb_acpi_setup, +}; + +int tb_acpi_init(void) +{ + return register_acpi_bus_type(&tb_acpi_bus); +} + +void tb_acpi_exit(void) +{ + unregister_acpi_bus_type(&tb_acpi_bus); +} |