[Mesa-dev] [PATCH 2/2] loader: add optional /sys filesystem method for PCI identification.
Gary Wong
gtw at gnu.org
Wed May 21 21:01:15 PDT 2014
Introduce a simple PCI identification method of looking up the answer
the /sys filesystem (available on Linux). Attempted after libudev, but
before DRM.
Disabled by default (available only when the --enable-sysfs configure
option is specified).
Signed-off-by: Gary Wong <gtw at gnu.org>
---
configure.ac | 36 +++++++++++------
src/loader/loader.c | 112 ++++++++++++++++++++++++++++++++++++++++++++++++++++
2 files changed, 137 insertions(+), 11 deletions(-)
diff --git a/configure.ac b/configure.ac
index 4e4d761..95f0e16 100644
--- a/configure.ac
+++ b/configure.ac
@@ -818,14 +818,21 @@ fi
case "$host_os" in
linux*)
- need_libudev=yes ;;
+ need_pci_id=yes ;;
*)
- need_libudev=no ;;
+ need_pci_id=no ;;
esac
PKG_CHECK_MODULES([LIBUDEV], [libudev >= $LIBUDEV_REQUIRED],
have_libudev=yes, have_libudev=no)
+AC_ARG_ENABLE([sysfs],
+ [AS_HELP_STRING([--enable-sysfs],
+ [enable /sys PCI identification @<:@default=disabled@:>@])],
+ [have_sysfs="$enableval"],
+ [have_sysfs=no]
+)
+
if test "x$enable_dri" = xyes; then
if test "$enable_static" = yes; then
AC_MSG_ERROR([Cannot use static libraries for DRI drivers])
@@ -910,8 +917,15 @@ xyesno)
;;
esac
+have_pci_id=no
if test "$have_libudev" = yes; then
DEFINES="$DEFINES -DHAVE_LIBUDEV"
+ have_pci_id=yes
+fi
+
+if test "$have_sysfs" = yes; then
+ DEFINES="$DEFINES -DHAVE_SYSFS"
+ have_pci_id=yes
fi
# This is outside the case (above) so that it is invoked even for non-GLX
@@ -1013,8 +1027,8 @@ if test "x$enable_dri" = xyes; then
DEFINES="$DEFINES -DHAVE_DRI3"
fi
- if test "x$have_libudev" != xyes; then
- AC_MSG_ERROR([libudev-dev required for building DRI])
+ if test "x$have_pci_id" != xyes; then
+ AC_MSG_ERROR([libudev-dev or sysfs required for building DRI])
fi
case "$host_cpu" in
@@ -1183,8 +1197,8 @@ if test "x$enable_gbm" = xauto; then
esac
fi
if test "x$enable_gbm" = xyes; then
- if test "x$need_libudev$have_libudev" = xyesno; then
- AC_MSG_ERROR([gbm requires udev >= $LIBUDEV_REQUIRED])
+ if test "x$need_pci_id$have_pci_id" = xyesno; then
+ AC_MSG_ERROR([gbm requires udev >= $LIBUDEV_REQUIRED or sysfs])
fi
if test "x$enable_dri" = xyes; then
@@ -1202,7 +1216,7 @@ if test "x$enable_gbm" = xyes; then
fi
fi
AM_CONDITIONAL(HAVE_GBM, test "x$enable_gbm" = xyes)
-if test "x$need_libudev" = xyes; then
+if test "x$need_pci_id$have_libudev" = xyesyes; then
GBM_PC_REQ_PRIV="libudev >= $LIBUDEV_REQUIRED"
else
GBM_PC_REQ_PRIV=""
@@ -1491,9 +1505,9 @@ for plat in $egl_platforms; do
;;
esac
- case "$plat$need_libudev$have_libudev" in
+ case "$plat$need_pci_id$have_pci_id" in
waylandyesno|drmyesno)
- AC_MSG_ERROR([cannot build $plat platform without udev >= $LIBUDEV_REQUIRED]) ;;
+ AC_MSG_ERROR([cannot build $plat platform without udev >= $LIBUDEV_REQUIRED or sysfs]) ;;
esac
done
@@ -1766,8 +1780,8 @@ gallium_require_llvm() {
gallium_require_drm_loader() {
if test "x$enable_gallium_loader" = xyes; then
- if test "x$need_libudev$have_libudev" = xyesno; then
- AC_MSG_ERROR([Gallium drm loader requires libudev >= $LIBUDEV_REQUIRED])
+ if test "x$need_pci_id$have_pci_id" = xyesno; then
+ AC_MSG_ERROR([Gallium drm loader requires libudev >= $LIBUDEV_REQUIRED or sysfs])
fi
if test "x$have_libdrm" != xyes; then
AC_MSG_ERROR([Gallium drm loader requires libdrm >= $LIBDRM_REQUIRED])
diff --git a/src/loader/loader.c b/src/loader/loader.c
index 52be706..0f26265 100644
--- a/src/loader/loader.c
+++ b/src/loader/loader.c
@@ -71,6 +71,10 @@
#include <assert.h>
#include <dlfcn.h>
#endif
+#ifdef HAVE_SYSFS
+#include <sys/stat.h>
+#include <sys/types.h>
+#endif
#include "loader.h"
#ifndef __NOT_HAVE_DRM_H
@@ -212,6 +216,66 @@ out:
}
#endif
+#if defined(HAVE_SYSFS)
+static int
+dev_node_from_fd(int fd, unsigned int *maj, unsigned int *min)
+{
+ struct stat buf;
+
+ if (fstat(fd, &buf) < 0) {
+ log_(_LOADER_WARNING, "MESA-LOADER: failed to stat fd %d\n", fd);
+ return -1;
+ }
+
+ if (!S_ISCHR(buf.st_mode)) {
+ log_(_LOADER_WARNING, "MESA-LOADER: fd %d not a character device\n", fd);
+ return -1;
+ }
+
+ *maj = major(buf.st_rdev);
+ *min = minor(buf.st_rdev);
+
+ return 0;
+}
+
+static int
+sysfs_get_pci_id_for_fd(int fd, int *vendor_id, int *chip_id)
+{
+ unsigned int maj, min;
+ FILE *f;
+ char buf[0x40];
+
+ if (dev_node_from_fd(fd, &maj, &min) < 0) {
+ *chip_id = -1;
+ return 0;
+ }
+
+ snprintf(buf, sizeof(buf), "/sys/dev/char/%d:%d/device/vendor", maj, min);
+ if (!(f = fopen(buf, "r"))) {
+ *chip_id = -1;
+ return 0;
+ }
+ if (fscanf(f, "%x", vendor_id) != 1) {
+ *chip_id = -1;
+ fclose(f);
+ return 0;
+ }
+ fclose(f);
+ snprintf(buf, sizeof(buf), "/sys/dev/char/%d:%d/device/device", maj, min);
+ if (!(f = fopen(buf, "r"))) {
+ *chip_id = -1;
+ return 0;
+ }
+ if (fscanf(f, "%x", chip_id) != 1) {
+ *chip_id = -1;
+ fclose(f);
+ return 0;
+ }
+ fclose(f);
+ return 1;
+}
+#endif
+
#if !defined(__NOT_HAVE_DRM_H)
/* for i915 */
#include <i915_drm.h>
@@ -291,6 +355,10 @@ loader_get_pci_id_for_fd(int fd, int *vendor_id, int *chip_id)
if (libudev_get_pci_id_for_fd(fd, vendor_id, chip_id))
return 1;
#endif
+#if HAVE_SYSFS
+ if (sysfs_get_pci_id_for_fd(fd, vendor_id, chip_id))
+ return 1;
+#endif
#if !defined(__NOT_HAVE_DRM_H)
if (drm_get_pci_id_for_fd(fd, vendor_id, chip_id))
return 1;
@@ -332,6 +400,46 @@ out:
#endif
+#if HAVE_SYSFS
+static char *
+sysfs_get_device_name_for_fd(int fd)
+{
+ char *device_name = NULL;
+ unsigned int maj, min;
+ FILE *f;
+ char buf[0x40];
+ static const char match[9] = "\0DEVNAME=";
+ int expected = 1;
+
+ if (dev_node_from_fd(fd, &maj, &min) < 0)
+ return NULL;
+
+ snprintf(buf, sizeof(buf), "/sys/dev/char/%d:%d/uevent", maj, min);
+ if (!(f = fopen(buf, "r")))
+ return NULL;
+
+ while (expected < sizeof(match)) {
+ int c = getc(f);
+
+ if (c == EOF) {
+ fclose(f);
+ return NULL;
+ } else if (c == match[expected] )
+ expected++;
+ else
+ expected = 0;
+ }
+
+ strcpy(buf, "/dev/");
+ if (fgets(buf + 5, sizeof(buf) - 5, f))
+ device_name = strdup(buf);
+
+ fclose(f);
+ return device_name;
+}
+#endif
+
+
char *
loader_get_device_name_for_fd(int fd)
{
@@ -341,6 +449,10 @@ loader_get_device_name_for_fd(int fd)
if ((result = libudev_get_device_name_for_fd(fd)))
return result;
#endif
+#if HAVE_SYSFS
+ if ((result = sysfs_get_device_name_for_fd(fd)))
+ return result;
+#endif
return result;
}
--
1.9.2
More information about the mesa-dev
mailing list