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+title: Raspberry 5 baremetal detect board
+keywords:raspi5,asm,c,kernel,arm64
+
+# Raspberry 5 baremetal detect board
+
+Baremetal code snippet on how to detect what raspi board you are running on
+
+```c
+int  get_raspi_board()
+{
+    unsigned int reg;
+    int ret=0;
+
+    /* read the system register */
+#if __aarch64__
+    asm volatile ("mrs %x0, midr_el1" : "=r" (reg));
+#else
+    asm volatile ("mrc p15,0,%0,c0,c0,0" : "=r" (reg));
+#endif
+
+    /* get the PartNum, detect board and MMIO base address */
+    switch ((reg >> 4) & 0xFFF) {
+        case 0xB76: 
+        	ret=1;
+        	break;
+        case 0xC07: 
+        	ret=2;
+        	break;
+        case 0xD03: 
+        	ret=3; 
+        	break;
+        case 0xD08: 
+        	ret=4; 
+        	break;
+        case 0xD0B:
+        	ret=5;
+        default: 
+        	break;
+    }
+    return ret;
+}
+
+```
+
+## Links
+
+[1] https://wiki.osdev.org/Detecting_Raspberry_Pi_Board  
+[2] [/writeup/raspberry5_baremetal_helloworld.md](/writeup/raspberry5_baremetal_helloworld.md)  
+[3] https://github.com/DSERIOUSGUY/HobOS/blob/main/mmio.c  
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