hwinfo: Make byAddress() ignore non-MMIO devices

1 files changed, 12 insertions, 1 deletions

diff --git a/src/hwinfo.zig b/src/hwinfo.zig
index 8e937c2..649f7c6 100644
--- a/src/hwinfo.zig
+++ b/src/hwinfo.zig
@@ -42,6 +42,16 @@ pub const DevKind = enum(u32) {
             else => false,
         };
     }
+
+    pub fn isMemoryMapped(self: DevKind) bool {
+        return switch (self) {
+            .cpus => false,
+            .plic => true,
+            .pcie => true,
+            .pci => true,
+            _ => false,
+        };
+    }
 };
 
 pub const Dev = extern struct {
@@ -132,6 +142,7 @@ pub fn byAddress(reg_addr: usize, only_user_manageable: bool) !?Dev {
     var it = try iterator();
     while (it.next()) |device| {
         const authorized = !only_user_manageable or device.kind.isUserManageable();
-        if (device.reg.addr == reg_addr and authorized) return device;
+        const eligible = device.kind.isMemoryMapped() and authorized;
+        if (device.reg.addr == reg_addr and eligible) return device;
     } else return null;
 }