From 46150305f28b0e5b9e8dbdb6182ed1caac33051c Mon Sep 17 00:00:00 2001
From: sebastian-dev <dev.sebastian@grams.de>
Date: Mon, 8 Feb 2021 10:50:06 +0100
Subject: [PATCH] AMD Ryzen, wrong CPU Core Enumeration (#376)

Thanks to @sebastian-dev
---
 .../Hardware/Cpu/Amd10Cpu.cs                  |  6 -----
 .../Hardware/Cpu/Amd17Cpu.cs                  | 23 +++++++++----------
 2 files changed, 11 insertions(+), 18 deletions(-)

diff --git a/LibreHardwareMonitorLib/Hardware/Cpu/Amd10Cpu.cs b/LibreHardwareMonitorLib/Hardware/Cpu/Amd10Cpu.cs
index 5d847b5..dc573be 100644
--- a/LibreHardwareMonitorLib/Hardware/Cpu/Amd10Cpu.cs
+++ b/LibreHardwareMonitorLib/Hardware/Cpu/Amd10Cpu.cs
@@ -125,11 +125,6 @@ namespace LibreHardwareMonitor.Hardware.CPU
                     }
                     break;
                 }
-                case 0x17:
-                {
-                    miscellaneousControlDeviceId = FAMILY_17H_MODEL_00_MISC_CONTROL_DEVICE_ID;
-                    break;
-                }
                 default:
                 {
                     miscellaneousControlDeviceId = 0;
@@ -565,7 +560,6 @@ namespace LibreHardwareMonitor.Hardware.CPU
         private const ushort FAMILY_15H_MODEL_70_MISC_CONTROL_DEVICE_ID = 0x15B3;
         private const ushort FAMILY_16H_MODEL_00_MISC_CONTROL_DEVICE_ID = 0x1533;
         private const ushort FAMILY_16H_MODEL_30_MISC_CONTROL_DEVICE_ID = 0x1583;
-        private const ushort FAMILY_17H_MODEL_00_MISC_CONTROL_DEVICE_ID = 0x1577;
 
         // ReSharper restore InconsistentNaming
     }
diff --git a/LibreHardwareMonitorLib/Hardware/Cpu/Amd17Cpu.cs b/LibreHardwareMonitorLib/Hardware/Cpu/Amd17Cpu.cs
index 22e5810..282da54 100644
--- a/LibreHardwareMonitorLib/Hardware/Cpu/Amd17Cpu.cs
+++ b/LibreHardwareMonitorLib/Hardware/Cpu/Amd17Cpu.cs
@@ -28,10 +28,8 @@ namespace LibreHardwareMonitor.Hardware.CPU
             _processor = new Processor(this);
 
             // add all numa nodes
-            const int initialCoreId = 1_000_000_000;
-
-            int coreId = 1;
-            int lastCoreId = initialCoreId;
+            int coreId = 0;
+            int lastCoreId = -1; //invalid id
 
             // Ryzen 3000's skip some core ids.
             // So start at 1 and count upwards when the read core changes.
@@ -39,22 +37,23 @@ namespace LibreHardwareMonitor.Hardware.CPU
             {
                 CpuId thread = cpu[0];
 
-                // coreID
-                // Register ..1E_1, [7:0]
+                // CPUID_Fn8000001E_EBX, Register ..1E_1, [7:0]
+                // threads per core =  CPUID_Fn8000001E_EBX[15:8] + 1
+                // CoreId: core ID =  CPUID_Fn8000001E_EBX[7:0]
                 int coreIdRead = (int)(thread.ExtData[0x1e, 1] & 0xff);
 
-                // nodeID
-                // Register ..1E_2, [7:0]
+                // CPUID_Fn8000001E_ECX, Node Identifiers, Register ..1E_2
+                // NodesPerProcessor =  CPUID_Fn8000001E_ECX[10:8]
+                // nodeID =  CPUID_Fn8000001E_ECX[7:0]
                 int nodeId = (int)(thread.ExtData[0x1e, 2] & 0xff);
 
-                _processor.AppendThread(thread, nodeId, coreId);
-
-                if (lastCoreId != initialCoreId && coreIdRead != lastCoreId)
+                if (coreIdRead != lastCoreId)
                 {
                     coreId++;
                 }
-
                 lastCoreId = coreIdRead;
+
+                _processor.AppendThread(thread, nodeId, coreId);
             }
 
             Update();