[PATCH libdrm 06/10] xf86drm: Add drmDevice support for virtio_gpu
Emil Velikov
emil.l.velikov at gmail.com
Mon Jun 25 17:36:22 UTC 2018
From: Emil Velikov <emil.velikov at collabora.com>
The GPU almost exclusively lives on the PCI bus, so we expose it as a
normal PCI one.
This allows any existing drmDevice users to work without any changes.
One could wonder why a separate typeset is not introduced, alike say
host1x. Unlike host1x the PCI/platform distinction for virtio provides
no extra information. Plus needed we can add the separate set at a later
stage.
Here are a couple of 'features' that virtio seems to be missing:
- provides extra information on top the plaform devices
- supports a range of GPU devices
- is considered hardware description (DT)
Signed-off-by: Emil Velikov <emil.velikov at collabora.com>
---
xf86drm.c | 13 ++++++++++++-
1 file changed, 12 insertions(+), 1 deletion(-)
diff --git a/xf86drm.c b/xf86drm.c
index 8ccd528f..b847ea26 100644
--- a/xf86drm.c
+++ b/xf86drm.c
@@ -2954,6 +2954,9 @@ sysfs_uevent_get(const char *path, const char *fmt, ...)
}
#endif
+/* Little white lie to avoid major rework of the existing code */
+#define DRM_BUS_VIRTIO 0x10
+
static int drmParseSubsystemType(int maj, int min)
{
#ifdef __linux__
@@ -2983,6 +2986,9 @@ static int drmParseSubsystemType(int maj, int min)
if (strncmp(name, "/host1x", 7) == 0)
return DRM_BUS_HOST1X;
+ if (strncmp(name, "/virtio", 7) == 0)
+ return DRM_BUS_VIRTIO;
+
return -EINVAL;
#elif defined(__OpenBSD__)
return DRM_BUS_PCI;
@@ -2996,7 +3002,7 @@ static char *
get_real_pci_path(int maj, int min)
{
char path[PATH_MAX + 1];
- char *real_path = malloc(PATH_MAX);
+ char *term, *real_path = malloc(PATH_MAX);
if (!real_path)
return NULL;
@@ -3007,6 +3013,10 @@ get_real_pci_path(int maj, int min)
return NULL;
}
+ term = strrchr(real_path, '/');
+ if (term && strncmp(term, "/virtio", 7) == 0)
+ *term = 0;
+
return real_path;
}
@@ -3744,6 +3754,7 @@ process_device(drmDevicePtr *device, const char *d_name,
switch (subsystem_type) {
case DRM_BUS_PCI:
+ case DRM_BUS_VIRTIO:
return drmProcessPciDevice(device, node, node_type, maj, min,
fetch_deviceinfo, flags);
case DRM_BUS_USB:
--
2.18.0
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