[igt-dev] [PATCH i-g-t v5 1/5] lib/igt_device: add igt_device_get_pci_addr by fd

Daniel Mrzyglod
2019-05-09T12:39:26Z

From: Michał Winiarski <michal.winiarski@intel.com>

This function get us pci address based by fd.
It allows us to make things a little bit more generic.
Also, we now require fd rather than doing guesswork when it comes to pci address.

v4: close sysfs fd
Signed-off-by: Michał Winiarski <michal.winiarski@intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Daniel Mrzyglod <daniel.t.mrzyglod@intel.com>
---
lib/igt_device.c | 124 +++++++++++++++++++++++++++++++++++++++++++++++
lib/igt_device.h | 1 +
2 files changed, 125 insertions(+)

diff --git a/lib/igt_device.c b/lib/igt_device.c
index 08f39c8b..88f35cad 100644
--- a/lib/igt_device.c
+++ b/lib/igt_device.c
@@ -21,11 +21,14 @@
* IN THE SOFTWARE.
*
*/
+#include <sys/types.h>
+#include <fcntl.h>

#include <sys/stat.h>
#include <sys/sysmacros.h>
#include "igt.h"
#include "igt_device.h"
+#include "igt_sysfs.h"

int __igt_device_set_master(int fd)
{
@@ -103,3 +106,124 @@ int igt_device_get_card_index(int fd)

return minor(st.st_rdev);
}
+
+#define IGT_DEV_PATH_LEN 80
+
+static bool igt_device_is_pci(int fd)
+{
+ char path[IGT_DEV_PATH_LEN];
+ char *subsystem;
+ int sysfs;
+ int len;
+
+ sysfs = igt_sysfs_open(fd);
+ if (sysfs == -1)
+ return false;
+
+ len = readlinkat(sysfs, "device/subsystem", path, sizeof(path) - 1);
+ close(sysfs);
+ if (len == -1)
+ return false;
+ path[len] = '\0';
+
+ subsystem = strrchr(path, '/');
+ if (!subsystem)
+ return false;
+
+ return strcmp(subsystem, "/pci") == 0;
+}
+
+struct igt_pci_addr {
+ unsigned int domain;
+ unsigned int bus;
+ unsigned int device;
+ unsigned int function;
+};
+
+static int igt_device_get_pci_addr(int fd, struct igt_pci_addr *pci)
+{
+ char path[IGT_DEV_PATH_LEN];
+ char *buf;
+ int sysfs;
+ int len;
+
+ if (!igt_device_is_pci(fd))
+ return -ENODEV;
+
+ sysfs = igt_sysfs_open(fd);
+ if (sysfs == -1)
+ return -ENOENT;
+
+ len = readlinkat(sysfs, "device", path, sizeof(path) - 1);
+ close(sysfs);
+ if (len == -1)
+ return -ENOENT;
+ path[len] = '\0';
+
+ buf = strrchr(path, '/');
+ if (!buf)
+ return -ENOENT;
+
+ if (sscanf(buf, "/%4x:%2x:%2x.%2x",
+ &pci->domain, &pci->bus,
+ &pci->device, &pci->function) != 4) {
+ igt_warn("Unable to extract PCI device address from '%s'\n", buf);
+ return -ENOENT;
+ }
+
+ return 0;
+}
+
+static struct pci_device *__igt_device_get_pci_device(int fd)
+{
+ struct igt_pci_addr pci_addr;
+ struct pci_device *pci_dev;
+
+ if (igt_device_get_pci_addr(fd, &pci_addr)) {
+ igt_warn("Unable to find device PCI address\n");
+ return NULL;
+ }
+
+ if (pci_system_init()) {
+ igt_warn("Couldn't initialize PCI system\n");
+ return NULL;
+ }
+
+ pci_dev = pci_device_find_by_slot(pci_addr.domain,
+ pci_addr.bus,
+ pci_addr.device,
+ pci_addr.function);
+ if (!pci_dev) {
+ igt_warn("Couldn't find PCI device %04x:%02x:%02x:%02x\n",
+ pci_addr.domain, pci_addr.bus,
+ pci_addr.device, pci_addr.function);
+ return NULL;
+ }
+
+ if (pci_device_probe(pci_dev)) {
+ igt_warn("Couldn't probe PCI device\n");
+ return NULL;
+ }
+
+ return pci_dev;
+}
+
+/**
+ * igt_device_get_pci_device:
+ *
+ * @fd: the device
+ *
+ * Looks up the main graphics pci device using libpciaccess.
+ *
+ * Returns:
+ * The pci_device, skips the test on any failures.
+ */
+struct pci_device *igt_device_get_pci_device(int fd)
+{
+ struct pci_device *pci_dev;
+
+ pci_dev = __igt_device_get_pci_device(fd);
+ igt_require(pci_dev);
+
+ return pci_dev;
+}
diff --git a/lib/igt_device.h b/lib/igt_device.h
index 9d7dc2c3..278ba7a9 100644
--- a/lib/igt_device.h
+++ b/lib/igt_device.h
@@ -32,5 +32,6 @@ int __igt_device_drop_master(int fd);
void igt_device_drop_master(int fd);

int igt_device_get_card_index(int fd);
+struct pci_device *igt_device_get_pci_device(int fd);

#endif /* __IGT_DEVICE_H__ */