1 // SPDX-License-Identifier: GPL-2.0 2 3 #include "../cpuflags.h" 4 #include "../string.h" 5 #include "../io.h" 6 #include "error.h" 7 8 #include <vdso/limits.h> 9 #include <uapi/asm/vmx.h> 10 11 #include <asm/shared/tdx.h> 12 13 /* Called from __tdx_hypercall() for unrecoverable failure */ 14 void __tdx_hypercall_failed(void) 15 { 16 error("TDVMCALL failed. TDX module bug?"); 17 } 18 19 static inline unsigned int tdx_io_in(int size, u16 port) 20 { 21 struct tdx_hypercall_args args = { 22 .r10 = TDX_HYPERCALL_STANDARD, 23 .r11 = EXIT_REASON_IO_INSTRUCTION, 24 .r12 = size, 25 .r13 = 0, 26 .r14 = port, 27 }; 28 29 if (__tdx_hypercall(&args, TDX_HCALL_HAS_OUTPUT)) 30 return UINT_MAX; 31 32 return args.r11; 33 } 34 35 static inline void tdx_io_out(int size, u16 port, u32 value) 36 { 37 struct tdx_hypercall_args args = { 38 .r10 = TDX_HYPERCALL_STANDARD, 39 .r11 = EXIT_REASON_IO_INSTRUCTION, 40 .r12 = size, 41 .r13 = 1, 42 .r14 = port, 43 .r15 = value, 44 }; 45 46 __tdx_hypercall(&args, 0); 47 } 48 49 static inline u8 tdx_inb(u16 port) 50 { 51 return tdx_io_in(1, port); 52 } 53 54 static inline void tdx_outb(u8 value, u16 port) 55 { 56 tdx_io_out(1, port, value); 57 } 58 59 static inline void tdx_outw(u16 value, u16 port) 60 { 61 tdx_io_out(2, port, value); 62 } 63 64 void early_tdx_detect(void) 65 { 66 u32 eax, sig[3]; 67 68 cpuid_count(TDX_CPUID_LEAF_ID, 0, &eax, &sig[0], &sig[2], &sig[1]); 69 70 if (memcmp(TDX_IDENT, sig, sizeof(sig))) 71 return; 72 73 /* Use hypercalls instead of I/O instructions */ 74 pio_ops.f_inb = tdx_inb; 75 pio_ops.f_outb = tdx_outb; 76 pio_ops.f_outw = tdx_outw; 77 } 78