Detect AMD GPU info via sysfs and block old cards

This wires up some new logic to start using sysfs to discover AMD GPU
information and detects old cards we can't yet support so we can fallback to CPU mode.

gpu/amd.go

+package gpu
+
+import (
+	"bufio"
+	"fmt"
+	"io"
+	"log/slog"
+	"os"
+	"path/filepath"
+	"strconv"
+	"strings"
+)
+
+// TODO - windows vs. non-windows vs darwin
+
+// Discovery logic for AMD/ROCm GPUs
+
+const (
+	DriverVersionFile     = "/sys/module/amdgpu/version"
+	GPUPropertiesFileGlob = "/sys/class/kfd/kfd/topology/nodes/*/properties"
+	// TODO probably break these down per GPU to make the logic simpler
+	GPUTotalMemoryFileGlob = "/sys/class/kfd/kfd/topology/nodes/*/mem_banks/*/properties" // size_in_bytes line
+	GPUUsedMemoryFileGlob  = "/sys/class/kfd/kfd/topology/nodes/*/mem_banks/*/used_memory"
+)
+
+func AMDDetected() bool {
+	_, err := AMDDriverVersion()
+	return err == nil
+}
+
+func AMDDriverVersion() (string, error) {
+	_, err := os.Stat(DriverVersionFile)
+	if err != nil {
+		return "", err
+	}
+	fp, err := os.Open(DriverVersionFile)
+	if err != nil {
+		return "", err
+	}
+	defer fp.Close()
+	verString, err := io.ReadAll(fp)
+	if err != nil {
+		return "", err
+	}
+	return strings.TrimSpace(string(verString)), nil
+}
+
+func AMDGFXVersions() []Version {
+	res := []Version{}
+	matches, _ := filepath.Glob(GPUPropertiesFileGlob)
+	for _, match := range matches {
+		fp, err := os.Open(match)
+		if err != nil {
+			slog.Debug(fmt.Sprintf("failed to open sysfs node file %s: %s", match, err))
+			continue
+		}
+		defer fp.Close()
+
+		scanner := bufio.NewScanner(fp)
+		// optionally, resize scanner's capacity for lines over 64K, see next example
+		for scanner.Scan() {
+			line := strings.TrimSpace(scanner.Text())
+			if strings.HasPrefix(line, "gfx_target_version") {
+				ver := strings.Fields(line)
+				if len(ver) != 2 || len(ver[1]) < 5 {
+					slog.Debug("malformed " + line)
+					continue
+				}
+				l := len(ver[1])
+				patch, err1 := strconv.ParseUint(ver[1][l-2:l], 10, 32)
+				minor, err2 := strconv.ParseUint(ver[1][l-4:l-2], 10, 32)
+				major, err3 := strconv.ParseUint(ver[1][:l-4], 10, 32)
+				if err1 != nil || err2 != nil || err3 != nil {
+					slog.Debug("malformed int " + line)
+					continue
+				}
+
+				res = append(res, Version{
+					Major: uint(major),
+					Minor: uint(minor),
+					Patch: uint(patch),
+				})
+			}
+		}
+	}
+	return res
+}
+
+func (v Version) ToGFXString() string {
+	return fmt.Sprintf("gfx%d%d%d", v.Major, v.Minor, v.Patch)
+}

gpu/gpu.go

@@ -149,43 +149,63 @@ func GetGPUInfo() GpuInfo {
 				slog.Info(fmt.Sprintf("CUDA GPU is too old. Falling back to CPU mode. Compute Capability detected: %d.%d", cc.major, cc.minor))
 			}
 		}
-	} else if gpuHandles.rocm != nil && (cpuVariant != "" || runtime.GOARCH != "amd64") {
-		C.rocm_check_vram(*gpuHandles.rocm, &memInfo)
-		if memInfo.err != nil {
-			slog.Info(fmt.Sprintf("error looking up ROCm GPU memory: %s", C.GoString(memInfo.err)))
-			C.free(unsafe.Pointer(memInfo.err))
-		} else if memInfo.igpu_index >= 0 && memInfo.count == 1 {
-			// Only one GPU detected and it appears to be an integrated GPU - skip it
-			slog.Info("ROCm unsupported integrated GPU detected")
-		} else if memInfo.count > 0 {
-			if memInfo.igpu_index >= 0 {
-				// We have multiple GPUs reported, and one of them is an integrated GPU
-				// so we have to set the env var to bypass it
-				// If the user has specified their own ROCR_VISIBLE_DEVICES, don't clobber it
-				val := os.Getenv("ROCR_VISIBLE_DEVICES")
-				if val == "" {
-					devices := []string{}
-					for i := 0; i < int(memInfo.count); i++ {
-						if i == int(memInfo.igpu_index) {
-							continue
+	} else if AMDDetected() && gpuHandles.rocm != nil && (cpuVariant != "" || runtime.GOARCH != "amd64") {
+		ver, err := AMDDriverVersion()
+		if err == nil {
+			slog.Info("AMD Driver: " + ver)
+		}
+		gfx := AMDGFXVersions()
+		tooOld := false
+		for _, v := range gfx {
+			if v.Major < 9 {
+				slog.Info("AMD GPU too old, falling back to CPU " + v.ToGFXString())
+				tooOld = true
+				break
+			}
+
+			// TODO - remap gfx strings for unsupporetd minor/patch versions to supported for the same major
+			// e.g. gfx1034 works if we map it to gfx1030 at runtime
+
+		}
+		if !tooOld {
+			// TODO - this algo can be shifted over to use sysfs instead of the rocm info library...
+			C.rocm_check_vram(*gpuHandles.rocm, &memInfo)
+			if memInfo.err != nil {
+				slog.Info(fmt.Sprintf("error looking up ROCm GPU memory: %s", C.GoString(memInfo.err)))
+				C.free(unsafe.Pointer(memInfo.err))
+			} else if memInfo.igpu_index >= 0 && memInfo.count == 1 {
+				// Only one GPU detected and it appears to be an integrated GPU - skip it
+				slog.Info("ROCm unsupported integrated GPU detected")
+			} else if memInfo.count > 0 {
+				if memInfo.igpu_index >= 0 {
+					// We have multiple GPUs reported, and one of them is an integrated GPU
+					// so we have to set the env var to bypass it
+					// If the user has specified their own ROCR_VISIBLE_DEVICES, don't clobber it
+					val := os.Getenv("ROCR_VISIBLE_DEVICES")
+					if val == "" {
+						devices := []string{}
+						for i := 0; i < int(memInfo.count); i++ {
+							if i == int(memInfo.igpu_index) {
+								continue
+							}
+							devices = append(devices, strconv.Itoa(i))
 						}
-						devices = append(devices, strconv.Itoa(i))
+						val = strings.Join(devices, ",")
+						os.Setenv("ROCR_VISIBLE_DEVICES", val)
 					}
-					val = strings.Join(devices, ",")
-					os.Setenv("ROCR_VISIBLE_DEVICES", val)
+					slog.Info(fmt.Sprintf("ROCm integrated GPU detected - ROCR_VISIBLE_DEVICES=%s", val))
 				}
-				slog.Info(fmt.Sprintf("ROCm integrated GPU detected - ROCR_VISIBLE_DEVICES=%s", val))
-			}
-			resp.Library = "rocm"
-			var version C.rocm_version_resp_t
-			C.rocm_get_version(*gpuHandles.rocm, &version)
-			verString := C.GoString(version.str)
-			if version.status == 0 {
-				resp.Variant = "v" + verString
-			} else {
-				slog.Info(fmt.Sprintf("failed to look up ROCm version: %s", verString))
+				resp.Library = "rocm"
+				var version C.rocm_version_resp_t
+				C.rocm_get_version(*gpuHandles.rocm, &version)
+				verString := C.GoString(version.str)
+				if version.status == 0 {
+					resp.Variant = "v" + verString
+				} else {
+					slog.Info(fmt.Sprintf("failed to look up ROCm version: %s", verString))
+				}
+				C.free(unsafe.Pointer(version.str))
 			}
-			C.free(unsafe.Pointer(version.str))
 		}
 	}
 	if resp.Library == "" {

gpu/types.go

@@ -16,3 +16,9 @@ type GpuInfo struct {
 
 	// TODO add other useful attributes about the card here for discovery information
 }
+
+type Version struct {
+	Major uint
+	Minor uint
+	Patch uint
+}

llm/generate/gen_linux.sh

@@ -21,7 +21,6 @@ amdGPUs() {
         return
     fi
     GPU_LIST=(
-        "gfx803"
         "gfx900"
         "gfx906:xnack-"
         "gfx908:xnack-"

llm/payload_common.go

@@ -90,6 +90,7 @@ func getDynLibs(gpuInfo gpu.GpuInfo) []string {
 	if len(dynLibs) == 0 {
 		dynLibs = []string{availableDynLibs["cpu"]}
 	}
+	slog.Debug(fmt.Sprintf("ordered list of LLM libraries to try %v", dynLibs))
 	return dynLibs
 }