On 01-11-2016 18:13, Emil Velikov wrote: > From: Emil Velikov <emil.velikov@xxxxxxxxxxxxx> > > Parsing config sysfs file wakes up the device. The latter of which may > be slow and isn't required to begin with. > > Reading through config is/was required since the revision is not > available by other means, although with a kernel patch in the way we can > 'cheat' temporarily. > > That should be fine, since no open-source project has ever used the > value. > > Cc: Michel Dänzer <michel.daenzer@xxxxxxx> > Cc: Mauro Santos <registo.mailling@xxxxxxxxx> > Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=98502 > Signed-off-by: Emil Velikov <emil.velikov@xxxxxxxxxxxxx> > --- > Mauro can you apply this against libdrm and rebuild it. You do _not_ > need to rebuild mesa afterwords. > > Thanks > --- > xf86drm.c | 50 +++++++++++++++++++++++++++++++++++--------------- > 1 file changed, 35 insertions(+), 15 deletions(-) > > diff --git a/xf86drm.c b/xf86drm.c > index 52add5e..5a5100c 100644 > --- a/xf86drm.c > +++ b/xf86drm.c > @@ -2950,25 +2950,45 @@ static int drmParsePciDeviceInfo(const char *d_name, > drmPciDeviceInfoPtr device) > { > #ifdef __linux__ > +#define ARRAY_SIZE(a) (sizeof(a) / sizeof((a)[0])) > + static const char *attrs[] = { > + "revision", /* XXX: make sure it's always first, see note below */ > + "vendor", > + "device", > + "subsystem_vendor", > + "subsystem_device", > + }; > char path[PATH_MAX + 1]; > - unsigned char config[64]; > - int fd, ret; > + unsigned int data[ARRAY_SIZE(attrs)]; > + FILE *fp; > + int ret; > > - snprintf(path, PATH_MAX, "/sys/class/drm/%s/device/config", d_name); > - fd = open(path, O_RDONLY); > - if (fd < 0) > - return -errno; > + for (unsigned i = 0; i < ARRAY_SIZE(attrs); i++) { > + snprintf(path, PATH_MAX, "/sys/class/drm/%s/device/%s", > + d_name, attrs[i]); > + fp = fopen(path, "r"); > + if (!fp) { > + /* Note: First we check the revision, since older kernels > + * may not have it. Default to zero in such cases. */ > + if (i == 0) { > + data[i] = 0; > + continue; > + } > + return -errno; > + } > > - ret = read(fd, config, sizeof(config)); > - close(fd); > - if (ret < 0) > - return -errno; > + ret = fscanf(fp, "%x", &data[i]); > + fclose(fp); > + if (ret != 1) > + return -errno; > + > + } > > - device->vendor_id = config[0] | (config[1] << 8); > - device->device_id = config[2] | (config[3] << 8); > - device->revision_id = config[8]; > - device->subvendor_id = config[44] | (config[45] << 8); > - device->subdevice_id = config[46] | (config[47] << 8); > + device->revision_id = data[0] & 0xff; > + device->vendor_id = data[1] & 0xffff; > + device->device_id = data[2] & 0xffff; > + device->subvendor_id = data[3] & 0xffff; > + device->subdevice_id = data[4] & 0xffff; > > return 0; > #else > I have applied this against libdrm 2.4.71 and I don't see any delays when starting firefox/chromium/thunderbird/glxgears. There is also no indication in dmesg that the dGPU is being reinitialized when starting the programs where I've detected the problem. -- Mauro Santos _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/dri-devel
