1 /* SPDX-License-Identifier: GPL-2.0 */ 2 #ifndef BOOT_IO_H 3 #define BOOT_IO_H 4 5 #include <asm/shared/io.h> 6 7 #undef inb 8 #undef inw 9 #undef inl 10 #undef outb 11 #undef outw 12 #undef outl 13 14 struct port_io_ops { 15 u8 (*f_inb)(u16 port); 16 void (*f_outb)(u8 v, u16 port); 17 void (*f_outw)(u16 v, u16 port); 18 }; 19 20 extern struct port_io_ops pio_ops; 21 22 /* 23 * Use the normal I/O instructions by default. 24 * TDX guests override these to use hypercalls. 25 */ init_default_io_ops(void)26 static inline void init_default_io_ops(void) 27 { 28 pio_ops.f_inb = __inb; 29 pio_ops.f_outb = __outb; 30 pio_ops.f_outw = __outw; 31 } 32 33 /* 34 * Redirect port I/O operations via pio_ops callbacks. 35 * TDX guests override these callbacks with TDX-specific helpers. 36 */ 37 #define inb pio_ops.f_inb 38 #define outb pio_ops.f_outb 39 #define outw pio_ops.f_outw 40 41 #endif 42