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Diffstat (limited to 'arch/x86/boot/compressed/tdx.c')
-rw-r--r--arch/x86/boot/compressed/tdx.c77
1 files changed, 77 insertions, 0 deletions
diff --git a/arch/x86/boot/compressed/tdx.c b/arch/x86/boot/compressed/tdx.c
new file mode 100644
index 000000000000..918a7606f53c
--- /dev/null
+++ b/arch/x86/boot/compressed/tdx.c
@@ -0,0 +1,77 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#include "../cpuflags.h"
+#include "../string.h"
+#include "../io.h"
+#include "error.h"
+
+#include <vdso/limits.h>
+#include <uapi/asm/vmx.h>
+
+#include <asm/shared/tdx.h>
+
+/* Called from __tdx_hypercall() for unrecoverable failure */
+void __tdx_hypercall_failed(void)
+{
+ error("TDVMCALL failed. TDX module bug?");
+}
+
+static inline unsigned int tdx_io_in(int size, u16 port)
+{
+ struct tdx_hypercall_args args = {
+ .r10 = TDX_HYPERCALL_STANDARD,
+ .r11 = EXIT_REASON_IO_INSTRUCTION,
+ .r12 = size,
+ .r13 = 0,
+ .r14 = port,
+ };
+
+ if (__tdx_hypercall(&args, TDX_HCALL_HAS_OUTPUT))
+ return UINT_MAX;
+
+ return args.r11;
+}
+
+static inline void tdx_io_out(int size, u16 port, u32 value)
+{
+ struct tdx_hypercall_args args = {
+ .r10 = TDX_HYPERCALL_STANDARD,
+ .r11 = EXIT_REASON_IO_INSTRUCTION,
+ .r12 = size,
+ .r13 = 1,
+ .r14 = port,
+ .r15 = value,
+ };
+
+ __tdx_hypercall(&args, 0);
+}
+
+static inline u8 tdx_inb(u16 port)
+{
+ return tdx_io_in(1, port);
+}
+
+static inline void tdx_outb(u8 value, u16 port)
+{
+ tdx_io_out(1, port, value);
+}
+
+static inline void tdx_outw(u16 value, u16 port)
+{
+ tdx_io_out(2, port, value);
+}
+
+void early_tdx_detect(void)
+{
+ u32 eax, sig[3];
+
+ cpuid_count(TDX_CPUID_LEAF_ID, 0, &eax, &sig[0], &sig[2], &sig[1]);
+
+ if (memcmp(TDX_IDENT, sig, sizeof(sig)))
+ return;
+
+ /* Use hypercalls instead of I/O instructions */
+ pio_ops.f_inb = tdx_inb;
+ pio_ops.f_outb = tdx_outb;
+ pio_ops.f_outw = tdx_outw;
+}