The platform bus currently matches a DPDK driver to a device only by comparing the kernel driver name bound to the device against the DPDK driver name. Devices bound to the generic vfio-platform kernel driver all report the same driver name, which carries no device identity, so a specific DPDK driver cannot claim its device this way.
Add of_device_is_compatible(), which reads the device-tree "compatible" strings exposed under the device's of_node in sysfs and compares them against a requested string. platform_bus_match() now falls back to matching the DPDK driver name or its alias against these compatible strings, letting a driver bind to a device identified by its device-tree "compatible" value. Signed-off-by: Gagandeep Singh <[email protected]> Acked-by: Chengwen Feng <[email protected]> --- doc/guides/rel_notes/release_26_11.rst | 9 +++++ drivers/bus/platform/platform.c | 49 +++++++++++++++++++++++++- 2 files changed, 57 insertions(+), 1 deletion(-) diff --git a/doc/guides/rel_notes/release_26_11.rst b/doc/guides/rel_notes/release_26_11.rst index f93a5ab960..c44b4de604 100644 --- a/doc/guides/rel_notes/release_26_11.rst +++ b/doc/guides/rel_notes/release_26_11.rst @@ -20,6 +20,15 @@ DPDK Release 26.11 ninja -C build doc xdg-open build/doc/guides/html/rel_notes/release_26_11.html +* **bus/platform: match devices by device-tree compatible string.** + + The platform bus now matches DPDK drivers against the device-tree + ``compatible`` sysfs strings exposed by each platform device, in + addition to the existing kernel driver name and device name checks. + This allows drivers to be probed by DT compatible string when the + kernel driver is the generic ``vfio-platform``, which carries no + device identity in its name. + New Features ------------ diff --git a/drivers/bus/platform/platform.c b/drivers/bus/platform/platform.c index 950306e2d9..c684177d32 100644 --- a/drivers/bus/platform/platform.c +++ b/drivers/bus/platform/platform.c @@ -1,5 +1,6 @@ /* SPDX-License-Identifier: BSD-3-Clause * Copyright(C) 2023 Marvell. + * Copyright 2026 NXP */ #include <uapi/linux/vfio.h> @@ -230,6 +231,41 @@ of_resource_name(const char *dev_name, int index) return NULL; } +/* + * Check whether any of the NUL-separated device-tree "compatible" strings + * exposed by the platform device matches the given string. + */ +static bool +of_device_is_compatible(const char *dev_name, const char *compat) +{ + char path[PATH_MAX], buf[BUFSIZ] = { }; + const char *s; + FILE *f; + size_t len; + + if (compat == NULL) + return false; + + snprintf(path, sizeof(path), PLATFORM_BUS_DEVICES_PATH "/%s/of_node/compatible", dev_name); + f = fopen(path, "r"); + if (f == NULL) + return false; + + /* Read the raw contents, preserving embedded NULL separators. */ + len = fread(buf, 1, sizeof(buf) - 1, f); + fclose(f); + if (len == 0) + return false; + + /* Bound the walk by the read length: some kernels omit the trailing NULL. */ + for (s = buf; s < buf + len; s += strlen(s) + 1) { + if (!strcmp(s, compat)) + return true; + } + + return false; +} + static int device_map_resources(struct rte_platform_device *pdev, unsigned int num) { @@ -393,7 +429,18 @@ platform_bus_match(const struct rte_driver *drv, const struct rte_device *dev) } /* match by device name */ - if (!strcmp(pdev->name, pdrv->driver.name)) + if (!strcmp(pdev->name, pdrv->driver.name)) { + match = true; + goto out; + } + + /* + * The generic vfio-platform kernel driver name carries no device + * identity, so fall back to matching the device-tree "compatible" + * strings against the DPDK driver name or alias. + */ + if (of_device_is_compatible(pdev->name, pdrv->driver.name) || + of_device_is_compatible(pdev->name, pdrv->driver.alias)) match = true; out: -- 2.25.1
