// QEMU's `-M virt` exposes no GPIO controller — the BCM2711 GPIO // matrix is a Pi specialty. The kernel still imports // `src/trace/pl011_uart.zig`, which carries Pi-specific // GPIO-pin-mux calls (extern fn gpio_pin_set_func / gpio_pin_enable) // for the secondary tracing UART; these no-op exports satisfy those // symbols. No virt code path invokes them at runtime. export fn gpio_pin_set_func(pin u8, func u8) void { _ = pin _ = func } export fn gpio_pin_enable(pin u8) void { _ = pin }