GPU (OpenBSD): adds native GPU detection support

CMakeLists.txt

@@ -878,7 +878,7 @@ elseif(OpenBSD)
         src/detection/displayserver/linux/xlib.c
         src/detection/font/font_linux.c
         src/detection/gpu/gpu_pci.c
-        src/detection/gpu/gpu_general.c
+        src/detection/gpu/gpu_obsd.c
         src/detection/gtk_qt/gtk.c
         src/detection/host/host_obsd.c
         src/detection/lm/lm_nosupport.c

src/detection/gpu/gpu_obsd.c

@@ -0,0 +1,95 @@
+#include "gpu.h"
+#include "common/io/io.h"
+
+#include <sys/param.h>
+#include <sys/ioctl.h>
+#include <fcntl.h>
+#include <dev/pci/pcireg.h>
+#include <dev/pci/pcidevs.h>
+#include <sys/pciio.h>
+
+static inline int pciReadConf(int fd, uint32_t bus, uint32_t device, uint32_t func, uint32_t reg, uint32_t* result)
+{
+    struct pci_io bdfr = {
+        .pi_sel = {
+            .pc_bus = bus,
+            .pc_dev = device,
+            .pc_func = func,
+        },
+        .pi_reg = reg,
+        .pi_width = 4,
+    };
+
+    if (ioctl(fd, PCIOCREAD, &bdfr) == -1)
+        return -1;
+
+    *result = bdfr.pi_data;
+    return 0;
+}
+
+const char* ffDetectGPUImpl(FF_MAYBE_UNUSED const FFGPUOptions* options, FFlist* gpus)
+{
+    char pciDevPath[] = "/dev/pci0";
+    FF_AUTO_CLOSE_FD int pcifd = open(pciDevPath, O_RDONLY | O_CLOEXEC);
+    if (pcifd < 0)
+        return "open(\"/dev/pci0\", O_RDONLY | O_CLOEXEC) failed";
+
+    for (uint32_t bus = 0; bus <= 255; bus++)
+    {
+        for (uint32_t dev = 0; dev < 32; dev++)
+        {
+            uint32_t maxfuncs = 0;
+            for (uint32_t func = 0; func <= maxfuncs; func++)
+            {
+                uint32_t pciid, pciclass;
+                if (pciReadConf(pcifd, bus, dev, func, PCI_ID_REG, &pciid) != 0)
+                    continue;
+
+                if (PCI_VENDOR(pciid) == PCI_VENDOR_INVALID || PCI_VENDOR(pciid) == 0)
+                    continue;
+
+                if (pciReadConf(pcifd, bus, dev, func, PCI_CLASS_REG, &pciclass) != 0)
+                    continue;
+
+                if (func == 0)
+                {
+                    // For some reason, pciReadConf returns success even for non-existing devices.
+                    // So we need to check for `PCI_VENDOR(pciid) == PCI_VENDOR_INVALID` above to filter them out.
+                    uint32_t bhlcr;
+                    if (pciReadConf(pcifd, bus, dev, 0, PCI_BHLC_REG, &bhlcr) != 0)
+                        continue;
+
+                    if (PCI_HDRTYPE_MULTIFN(bhlcr)) maxfuncs = 7;
+                }
+
+                if (PCI_CLASS(pciclass) != PCI_CLASS_DISPLAY)
+                    continue;
+
+                if (func > 0 && PCI_SUBCLASS(pciclass) == PCI_SUBCLASS_DISPLAY_MISC)
+                    continue; // Likely an auxiliary display controller (#2034)
+
+                FFGPUResult* gpu = (FFGPUResult*)ffListAdd(gpus);
+                ffStrbufInitStatic(&gpu->vendor, ffGPUGetVendorString(PCI_VENDOR(pciid)));
+                ffStrbufInit(&gpu->name);
+                ffStrbufInit(&gpu->driver);
+                ffStrbufInitS(&gpu->platformApi, "/dev/pci0");
+                ffStrbufInit(&gpu->memoryType);
+                gpu->index = FF_GPU_INDEX_UNSET;
+                gpu->temperature = FF_GPU_TEMP_UNSET;
+                gpu->coreCount = FF_GPU_CORE_COUNT_UNSET;
+                gpu->coreUsage = FF_GPU_CORE_USAGE_UNSET;
+                gpu->type = FF_GPU_TYPE_UNKNOWN;
+                gpu->dedicated.total = gpu->dedicated.used = gpu->shared.total = gpu->shared.used = FF_GPU_VMEM_SIZE_UNSET;
+                gpu->deviceId = ffGPUPciAddr2Id(0, bus, dev, func);
+                gpu->frequency = FF_GPU_FREQUENCY_UNSET;
+
+                if (gpu->vendor.chars == FF_GPU_VENDOR_NAME_AMD)
+                    ffGPUQueryAmdGpuName(PCI_PRODUCT(pciid), PCI_REVISION(pciid), gpu);
+                if (gpu->name.length == 0)
+                    ffGPUFillVendorAndName(PCI_SUBCLASS(pciclass), PCI_VENDOR(pciid), PCI_PRODUCT(pciid), gpu);
+            }
+        }
+    }
+
+    return NULL;
+}