From 5febf432df1cfa5b25d99b54c32103fafbdd0eb9 Mon Sep 17 00:00:00 2001 From: Miguel Ojeda Date: Sun, 16 Aug 2026 15:32:33 +0200 Subject: kbuild: rust: keep Rust objects out of Clang LTO with inline helpers Under `CONFIG_LTO_CLANG` + `CONFIG_RUST_INLINE_HELPERS`, one may hit `objtool` errors such as: vmlinux.o: error: objtool: _R..._3Gsp4boot+0xd6a: can't find jump dest instruction at .text._R..._3Gsp4boot+0x1dfd The reason is that in such builds, the Clang invocation that compiles the combined Rust plus helpers bitcode emits LLVM bitcode (again) -- the final code generation happens in the linker's LTO step, which the `-mllvm` trap options passed to Clang do not reach. This, in turn, means that unreachable traps are missing, and the impossible paths do not merely fallthrough to the next symbol, but past the end of their own section, since LTO builds place each function in its own section. Thus filter `CC_FLAGS_LTO` out of the Clang invocation, so that it always emits machine code directly, with the traps in place. Assisted-by: LLM Cc: Gary Guo Cc: Boqun Feng Cc: Alice Ryhl Cc: Matthew Maurer Cc: Josh Poimboeuf Cc: Peter Zijlstra Cc: stable@vger.kernel.org Fixes: 3a2486cc1da5 ("kbuild: rust: provide an option to inline C helpers into Rust") Acked-by: Gary Guo Link: https://patch.msgid.link/20260816133233.197500-2-ojeda@kernel.org Signed-off-by: Miguel Ojeda --- drivers/soundwire/slave.c | 286 ++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 286 insertions(+) create mode 100644 drivers/soundwire/slave.c (limited to 'drivers/soundwire/slave.c') diff --git a/drivers/soundwire/slave.c b/drivers/soundwire/slave.c new file mode 100644 index 000000000..e0c49cbcb --- /dev/null +++ b/drivers/soundwire/slave.c @@ -0,0 +1,286 @@ +// SPDX-License-Identifier: (GPL-2.0 OR BSD-3-Clause) +// Copyright(c) 2015-17 Intel Corporation. + +#include +#include +#include +#include +#include +#include "bus.h" +#include "sysfs_local.h" + +static void sdw_slave_release(struct device *dev) +{ + struct sdw_slave *slave = dev_to_sdw_dev(dev); + + of_node_put(slave->dev.of_node); + mutex_destroy(&slave->sdw_dev_lock); + kfree(slave); +} + +const struct device_type sdw_slave_type = { + .name = "sdw_slave", + .release = sdw_slave_release, + .uevent = sdw_slave_uevent, +}; +EXPORT_SYMBOL_GPL(sdw_slave_type); + +int sdw_slave_add(struct sdw_bus *bus, + struct sdw_slave_id *id, struct fwnode_handle *fwnode) +{ + struct sdw_slave *slave; + int ret; + int i; + + slave = kzalloc_obj(*slave); + if (!slave) + return -ENOMEM; + + /* Initialize data structure */ + memcpy(&slave->id, id, sizeof(*id)); + slave->dev.parent = bus->dev; + slave->dev.fwnode = fwnode; + + if (id->unique_id == SDW_IGNORED_UNIQUE_ID) { + /* name shall be sdw:ctrl:link:mfg:part:class */ + dev_set_name(&slave->dev, "sdw:%01x:%01x:%04x:%04x:%02x", + bus->controller_id, bus->link_id, id->mfg_id, id->part_id, + id->class_id); + } else { + /* name shall be sdw:ctrl:link:mfg:part:class:unique */ + dev_set_name(&slave->dev, "sdw:%01x:%01x:%04x:%04x:%02x:%01x", + bus->controller_id, bus->link_id, id->mfg_id, id->part_id, + id->class_id, id->unique_id); + } + + slave->dev.bus = &sdw_bus_type; + slave->dev.of_node = of_node_get(to_of_node(fwnode)); + slave->dev.type = &sdw_slave_type; + slave->dev.groups = sdw_slave_status_attr_groups; + slave->bus = bus; + slave->status = SDW_SLAVE_UNATTACHED; + init_completion(&slave->enumeration_complete); + init_completion(&slave->initialization_complete); + slave->dev_num = 0; + slave->probed = false; + slave->first_interrupt_done = false; + mutex_init(&slave->sdw_dev_lock); + + for (i = 0; i < SDW_MAX_PORTS; i++) + init_completion(&slave->port_ready[i]); + + mutex_lock(&bus->bus_lock); + list_add_tail(&slave->node, &bus->slaves); + mutex_unlock(&bus->bus_lock); + + /* + * The Soundwire driver probe may optionally register SDCA + * sub-devices, one per Function. This means the information + * on the SDCA revision and the number/type of Functions need + * to be extracted from platform firmware before the SoundWire + * driver probe, and as a consequence before the SoundWire + * device_register() below. + */ + sdca_lookup_interface_revision(slave); + sdca_lookup_functions(slave); + + ret = device_register(&slave->dev); + if (ret) { + dev_err(bus->dev, "Failed to add slave: ret %d\n", ret); + + /* + * On err, don't free but drop ref as this will be freed + * when release method is invoked. + */ + mutex_lock(&bus->bus_lock); + list_del(&slave->node); + mutex_unlock(&bus->bus_lock); + put_device(&slave->dev); + + return ret; + } + sdw_slave_debugfs_init(slave); + + return ret; +} +EXPORT_SYMBOL(sdw_slave_add); + +#if IS_ENABLED(CONFIG_ACPI) + +static bool find_slave(struct sdw_bus *bus, + struct acpi_device *adev, + struct sdw_slave_id *id) +{ + unsigned int link_id; + u64 addr; + int ret; + + if (acpi_bus_get_status(adev) || !acpi_dev_ready_for_enumeration(adev)) + return false; + + ret = acpi_get_local_u64_address(adev->handle, &addr); + if (ret < 0) + return false; + + if (bus->ops->override_adr) + addr = bus->ops->override_adr(bus, addr); + + if (!addr) + return false; + + /* Extract link id from ADR, Bit 51 to 48 (included) */ + link_id = SDW_DISCO_LINK_ID(addr); + + /* Check for link_id match */ + if (link_id != bus->link_id) + return false; + + sdw_extract_slave_id(bus, addr, id); + + return true; +} + +struct sdw_acpi_child_walk_data { + struct sdw_bus *bus; + struct acpi_device *adev; + struct sdw_slave_id id; + bool ignore_unique_id; +}; + +static int sdw_acpi_check_duplicate(struct acpi_device *adev, void *data) +{ + struct sdw_acpi_child_walk_data *cwd = data; + struct sdw_bus *bus = cwd->bus; + struct sdw_slave_id id; + + if (adev == cwd->adev) + return 0; + + if (!find_slave(bus, adev, &id)) + return 0; + + if (cwd->id.sdw_version != id.sdw_version || cwd->id.mfg_id != id.mfg_id || + cwd->id.part_id != id.part_id || cwd->id.class_id != id.class_id) + return 0; + + if (cwd->id.unique_id != id.unique_id) { + dev_dbg(bus->dev, + "Valid unique IDs 0x%x 0x%x for Slave mfg_id 0x%04x, part_id 0x%04x\n", + cwd->id.unique_id, id.unique_id, cwd->id.mfg_id, + cwd->id.part_id); + cwd->ignore_unique_id = false; + return 0; + } + + dev_err(bus->dev, + "Invalid unique IDs 0x%x 0x%x for Slave mfg_id 0x%04x, part_id 0x%04x\n", + cwd->id.unique_id, id.unique_id, cwd->id.mfg_id, cwd->id.part_id); + return -ENODEV; +} + +static int sdw_acpi_find_one(struct acpi_device *adev, void *data) +{ + struct sdw_bus *bus = data; + struct sdw_acpi_child_walk_data cwd = { + .bus = bus, + .adev = adev, + .ignore_unique_id = true, + }; + int ret; + + if (!find_slave(bus, adev, &cwd.id)) + return 0; + + /* Brute-force O(N^2) search for duplicates. */ + ret = acpi_dev_for_each_child(ACPI_COMPANION(bus->dev), + sdw_acpi_check_duplicate, &cwd); + if (ret) + return ret; + + if (cwd.ignore_unique_id) + cwd.id.unique_id = SDW_IGNORED_UNIQUE_ID; + + /* Ignore errors and continue. */ + sdw_slave_add(bus, &cwd.id, acpi_fwnode_handle(adev)); + return 0; +} + +/* + * sdw_acpi_find_slaves() - Find Slave devices in Master ACPI node + * @bus: SDW bus instance + * + * Scans Master ACPI node for SDW child Slave devices and registers it. + */ +int sdw_acpi_find_slaves(struct sdw_bus *bus) +{ + struct acpi_device *parent; + + parent = ACPI_COMPANION(bus->dev); + if (!parent) { + dev_err(bus->dev, "Can't find parent for acpi bind\n"); + return -ENODEV; + } + + return acpi_dev_for_each_child(parent, sdw_acpi_find_one, bus); +} + +#endif + +/* + * sdw_of_find_slaves() - Find Slave devices in master device tree node + * @bus: SDW bus instance + * + * Scans Master DT node for SDW child Slave devices and registers it. + */ +int sdw_of_find_slaves(struct sdw_bus *bus) +{ + struct device *dev = bus->dev; + struct device_node *node; + + for_each_child_of_node(bus->dev->of_node, node) { + int link_id, ret, len; + unsigned int sdw_version; + const char *compat = NULL; + struct sdw_slave_id id; + const __be32 *addr; + + ret = of_property_read_string(node, "compatible", &compat); + if (ret) + continue; + + ret = sscanf(compat, "sdw%01x%04hx%04hx%02hhx", &sdw_version, + &id.mfg_id, &id.part_id, &id.class_id); + + if (ret != 4) { + dev_err(dev, "Invalid compatible string found %s\n", + compat); + continue; + } + + addr = of_get_property(node, "reg", &len); + if (!addr || (len < 2 * sizeof(u32))) { + dev_err(dev, "Invalid Link and Instance ID\n"); + continue; + } + + link_id = be32_to_cpup(addr++); + id.unique_id = be32_to_cpup(addr); + id.sdw_version = sdw_version; + + /* Check for link_id match */ + if (link_id != bus->link_id) + continue; + + sdw_slave_add(bus, &id, of_fwnode_handle(node)); + } + + return 0; +} + +struct device *of_sdw_find_device_by_node(struct device_node *np) +{ + return bus_find_device_by_of_node(&sdw_bus_type, np); +} +EXPORT_SYMBOL_GPL(of_sdw_find_device_by_node); + +MODULE_IMPORT_NS("SND_SOC_SDCA"); -- cgit v1.3.1