Validate EEPROM after writing it

Signed-off-by: Daniel Schaefer <dhs@frame.work>

Author: JohnAZoidberg

framework_lib/src/chromium_ec/mod.rs

@@ -1526,6 +1526,24 @@ impl CrosEc {
         return_val
     }
 
+    pub fn validate_gpu_descriptor(&self, reference_desc: &[u8]) -> EcResult<bool> {
+        let current_desc = self.read_gpu_descriptor()?;
+        let max_len = core::cmp::max(current_desc.len(), reference_desc.len());
+        let mut valid = true;
+        for i in 0..max_len {
+            let expected = reference_desc.get(i);
+            let actual = current_desc.get(i);
+            if expected != actual {
+                println!(
+                    "  Offset 0x{:04X}: expected {:02X?}, got {:02X?}",
+                    i, expected, actual
+                );
+                valid = false;
+            }
+        }
+        Ok(valid)
+    }
+
     pub fn read_gpu_descriptor(&self) -> EcResult<Vec<u8>> {
         let header = self.read_gpu_desc_header()?;
         if header.magic != [0x32, 0xAC, 0x00, 0x00] {

framework_lib/src/commandline/mod.rs

@@ -1807,7 +1807,15 @@ pub fn run_with_args(args: &Cli, _allupdate: bool) -> i32 {
                 println!("  Size:       {:>20} KB", data.len() / 1024);
                 let res = ec.set_gpu_descriptor(&data, args.dry_run);
                 match res {
-                    Ok(()) => println!("GPU Descriptor successfully written"),
+                    Ok(()) => {
+                        println!("GPU Descriptor successfully written");
+                        println!("Validating GPU Descriptor...");
+                        match ec.validate_gpu_descriptor(&data) {
+                            Ok(true) => println!("  Validation passed"),
+                            Ok(false) => println!("  Validation FAILED: read-back mismatch"),
+                            Err(err) => println!("  Validation error: {:?}", err),
+                        }
+                    }
                     Err(err) => println!("GPU Descriptor write failed with error:  {:?}", err),
                 }
             }