From: Jan Viktorin <vikto...@rehivetech.com>
Default implementation which scans the sysfs platform devices hierarchy.
For each device, extract the ueven and convert into rte_soc_device.
The information populated can then be used in probe to match against
the drivers registered.
Signed-off-by: Jan Viktorin <viktorin at rehivetech.com>
[Shreyansh: restructure commit to be an optional implementation]
Signed-off-by: Shreyansh Jain <shreyansh.jain at nxp.com>
--
v5:
- Update rte_eal_soc_scan to rte_eal_soc_scan_platform_bus
- Fix comments over scan and match functions
---
lib/librte_eal/common/include/rte_soc.h | 16 +-
lib/librte_eal/linuxapp/eal/eal_soc.c | 315 ++++++++++++++++++++++++++++++++
2 files changed, 329 insertions(+), 2 deletions(-)
diff --git a/lib/librte_eal/common/include/rte_soc.h
b/lib/librte_eal/common/include/rte_soc.h
index 38f897d..8be3db7 100644
--- a/lib/librte_eal/common/include/rte_soc.h
+++ b/lib/librte_eal/common/include/rte_soc.h
@@ -64,7 +64,10 @@ TAILQ_HEAD(soc_driver_list, rte_soc_driver); /**< SoC
drivers in D-linked Q. */
TAILQ_HEAD(soc_device_list, rte_soc_device); /**< SoC devices in D-linked Q. */
struct rte_soc_id {
- const char *compatible; /**< OF compatible specification */
+ union {
+ const char *compatible; /**< OF compatible specification */
+ char *_compatible;
+ };
uint64_t priv_data; /**< SoC Driver specific data */
};
@@ -200,7 +203,16 @@ rte_eal_parse_soc_spec(const char *spec, struct
rte_soc_addr *addr)
}
/**
- * Default function for matching the Soc driver with device. Each driver can
+ * Helper function for scanning for new SoC devices on platform bus.
+ *
+ * @return
+ * 0 on success
+ * !0 on failure to scan
+ */
+int rte_eal_soc_scan_platform_bus(void);
+
+/**
+ * Helper function for matching the Soc driver with device. Each driver can
* either use this function or define their own soc matching function.
* This function relies on the compatible string extracted from sysfs. But,
* a SoC might have different way of identifying its devices. Such SoC can
diff --git a/lib/librte_eal/linuxapp/eal/eal_soc.c
b/lib/librte_eal/linuxapp/eal/eal_soc.c
index 3929a76..d8dfe97 100644
--- a/lib/librte_eal/linuxapp/eal/eal_soc.c
+++ b/lib/librte_eal/linuxapp/eal/eal_soc.c
@@ -48,6 +48,321 @@
#include <eal_filesystem.h>
#include <eal_private.h>
+/** Pathname of SoC devices directory. */
+#define SYSFS_SOC_DEVICES "/sys/bus/platform/devices"
+
+static const char *
+soc_get_sysfs_path(void)
+{
+ const char *path = NULL;
+
+ path = getenv("SYSFS_SOC_DEVICES");
+ if (path == NULL)
+ return SYSFS_SOC_DEVICES;
+
+ return path;
+}
+
+static char *
+dev_read_uevent(const char *dirname)
+{
+ char filename[PATH_MAX];
+ struct stat st;
+ char *buf;
+ ssize_t total = 0;
+ int fd;
+
+ snprintf(filename, sizeof(filename), "%s/uevent", dirname);
+ fd = open(filename, O_RDONLY);
+ if (fd < 0) {
+ RTE_LOG(WARNING, EAL, "Failed to open file %s\n", filename);
+ return strdup("");
+ }
+
+ if (fstat(fd, &st) < 0) {
+ RTE_LOG(ERR, EAL, "Failed to stat file %s\n", filename);
+ close(fd);
+ return NULL;
+ }
+
+ if (st.st_size == 0) {
+ close(fd);
+ return strdup("");
+ }
+
+ buf = malloc(st.st_size + 1);
+ if (buf == NULL) {
+ RTE_LOG(ERR, EAL, "Failed to alloc memory to read %s\n",
+ filename);
+ close(fd);
+ return NULL;
+ }
+
+ while (total < st.st_size) {
+ ssize_t rlen = read(fd, buf + total, st.st_size - total);
+ if (rlen < 0) {
+ if (errno == EINTR)
+ continue;
+
+ RTE_LOG(ERR, EAL, "Failed to read file %s\n", filename);
+
+ free(buf);
+ close(fd);
+ return NULL;
+ }
+ if (rlen == 0) /* EOF */
+ break;
+
+ total += rlen;
+ }
+
+ buf[total] = '\0';
+ close(fd);
+
+ return buf;
+}
+
+static const char *
+dev_uevent_find(const char *uevent, const char *key)
+{
+ const size_t keylen = strlen(key);
+ const size_t total = strlen(uevent);
+ const char *p = uevent;
+
+ /* check whether it is the first key */
+ if (!strncmp(uevent, key, keylen))
+ return uevent + keylen;
+
+ /* check 2nd key or further... */
+ do {
+ p = strstr(p, key);
+ if (p == NULL)
+ break;
+
+ if (p[-1] == '\n') /* check we are at a new line */
+ return p + keylen;
+
+ p += keylen; /* skip this one */
+ } while (p - uevent < (ptrdiff_t) total);
+
+ return NULL;
+}
+
+static char *
+strdup_until_nl(const char *p)
+{
+ const char *nl = strchr(p, '\n');
+ if (nl == NULL)
+ return strdup(p); /* no newline, copy until '\0' */
+
+ return strndup(p, nl - p);
+}
+
+static int
+dev_parse_uevent(struct rte_soc_device *dev, const char *uevent)
+{
+ const char *of;
+ const char *compat_n;
+ char *err;
+ long n;
+ char compat[strlen("OF_COMPATIBLE_NNNN=")];
+ long i;
+
+ of = dev_uevent_find(uevent, "OF_FULLNAME=");
+ if (of == NULL)
+ return 1; /* don't care about this device */
+
+ dev->addr.fdt_path = strdup_until_nl(of);
+ if (dev->addr.fdt_path == NULL) {
+ RTE_LOG(ERR, PMD,
+ "Failed to alloc memory for fdt_path\n");
+ return -1;
+ }
+
+ RTE_LOG(DEBUG, EAL, "Detected device %s (%s)\n",
+ dev->addr.name, dev->addr.fdt_path);
+
+ compat_n = dev_uevent_find(uevent, "OF_COMPATIBLE_N=");
+ if (compat_n == NULL) {
+ RTE_LOG(ERR, EAL, "No OF_COMPATIBLE_N found\n");
+ return -1;
+ }
+
+ n = strtoul(compat_n, &err, 0);
+ if (*err != '\n' && err != NULL) {
+ RTE_LOG(ERR, EAL, "Failed to parse OF_COMPATIBLE_N: %.10s\n",
+ err);
+ goto fail_fdt_path;
+ }
+
+ if (n == 0)
+ return 1; /* cannot match anything */
+ if (n > 9999) { /* match NNNN */
+ RTE_LOG(ERR, EAL, "OF_COMPATIBLE_N is invalid: %ld\n", n);
+ goto fail_fdt_path;
+ }
+
+ dev->id = calloc(n + 1, sizeof(*dev->id));
+ if (dev->id == NULL) {
+ RTE_LOG(ERR, PMD, "Failed to alloc memory for ID\n");
+ free(dev->addr.fdt_path);
+ return -1;
+ }
+
+ for (i = 0; i < n; ++i) {
+ snprintf(compat, sizeof(compat), "OF_COMPATIBLE_%lu=", i);
+ const char *val;
+
+ val = dev_uevent_find(uevent, compat);
+ if (val == NULL) {
+ RTE_LOG(ERR, EAL, "%s was not found\n", compat);
+ goto fail_id;
+ }
+
+ dev->id[i]._compatible = strdup_until_nl(val);
+ if (dev->id[i]._compatible == NULL) {
+ RTE_LOG(ERR, PMD,
+ "Failed to alloc memory for compatible\n");
+ goto fail_id;
+ }
+
+ RTE_LOG(DEBUG, EAL, " compatible: %s\n",
+ dev->id[i].compatible);
+ }
+
+ dev->id[n]._compatible = NULL; /* mark last one */
+
+ return 0;
+
+fail_id:
+ while (i-- >= 0)
+ free(dev->id[i]._compatible);
+ free(dev->id);
+fail_fdt_path:
+ free(dev->addr.fdt_path);
+ return -1;
+}
+
+static void
+dev_content_free(struct rte_soc_device *dev)
+{
+ int i;
+
+ if (dev->addr.fdt_path)
+ free(dev->addr.fdt_path);
+
+ if (dev->id != NULL) {
+ for (i = 0; dev->id[i]._compatible; ++i)
+ free(dev->id[i]._compatible);
+
+ free(dev->id);
+ dev->id = NULL;
+ }
+}
+
+/**
+ * Scan one SoC sysfs entry, and fill the devices list from it.
+ * We require to have the uevent file with records: OF_FULLNAME and
+ * OF_COMPATIBLE array (with at least one entry). Otherwise, such device
+ * is skipped.
+ */
+static int
+soc_scan_one(const char *dirname, const char *name)
+{
+ struct rte_soc_device *dev;
+ char *uevent;
+ int ret;
+
+ uevent = dev_read_uevent(dirname);
+ if (uevent == NULL)
+ return -1;
+
+ if (uevent[0] == '\0') {
+ /* ignore directory without uevent file */
+ free(uevent);
+ return 1;
+ }
+
+ dev = malloc(sizeof(*dev) + strlen(name) + 1);
+ if (dev == NULL) {
+ RTE_LOG(ERR, PMD, "Failed to alloc memory for %s\n", name);
+ free(uevent);
+ return -1;
+ }
+
+ memset(dev, 0, sizeof(*dev));
+ dev->addr.name = (char *) (dev + 1);
+ strcpy(dev->addr.name, name);
+
+ ret = dev_parse_uevent(dev, uevent);
+ if (ret)
+ goto fail;
+ free(uevent); /* not needed anymore */
+
+ /* device is valid, add in list (sorted) */
+ if (TAILQ_EMPTY(&soc_device_list)) {
+ TAILQ_INSERT_TAIL(&soc_device_list, dev, next);
+ } else {
+ struct rte_soc_device *dev2;
+
+ TAILQ_FOREACH(dev2, &soc_device_list, next) {
+ ret = rte_eal_compare_soc_addr(&dev->addr, &dev2->addr);
+ if (ret > 0)
+ continue;
+
+ if (ret < 0) {
+ TAILQ_INSERT_BEFORE(dev2, dev, next);
+ } else { /* already registered */
+ dev_content_free(dev2);
+ dev2->addr.fdt_path = dev->addr.fdt_path;
+ dev2->id = dev->id;
+ free(dev);
+ }
+ return 0;
+ }
+ TAILQ_INSERT_TAIL(&soc_device_list, dev, next);
+ }
+
+ return 0;
+
+fail:
+ free(uevent);
+ dev_content_free(dev);
+ free(dev);
+ return ret;
+}
+
+int
+rte_eal_soc_scan_platform_bus(void)
+{
+ struct dirent *e;
+ DIR *dir;
+ char dirname[PATH_MAX];
+
+ dir = opendir(soc_get_sysfs_path());
+ if (dir == NULL) {
+ RTE_LOG(ERR, EAL, "%s(): opendir failed: %s\n",
+ __func__, strerror(errno));
+ return -1;
+ }
+
+ while ((e = readdir(dir)) != NULL) {
+ if (e->d_name[0] == '.')
+ continue;
+
+ snprintf(dirname, sizeof(dirname), "%s/%s",
+ soc_get_sysfs_path(), e->d_name);
+ if (soc_scan_one(dirname, e->d_name) < 0)
+ goto error;
+ }
+ closedir(dir);
+ return 0;
+
+error:
+ closedir(dir);
+ return -1;
+}
+
/* Init the SoC EAL subsystem */
int
rte_eal_soc_init(void)
--
2.7.4
