1 files changed, 75 insertions, 0 deletions
diff --git a/lib/i386-io-access.h b/lib/i386-io-access.h
new file mode 100644
index 0000000..8b1ad5f
--- /dev/null
+++ b/lib/i386-io-access.h
@@ -0,0 +1,75 @@
+/*
+ *	The PCI Library -- Compiler-specific wrappers around x86 I/O port access instructions
+ *
+ *	Copyright (c) 2023 Pali Rohár <pali@kernel.org>
+ *
+ *	Can be freely distributed and used under the terms of the GNU GPL v2+
+ *
+ *	SPDX-License-Identifier: GPL-2.0-or-later
+ */
+
+#if defined(__GNUC__)
+
+static inline unsigned char
+intel_inb(unsigned short int port)
+{
+  unsigned char value;
+  asm volatile ("inb %w1, %0" : "=a" (value) : "Nd" (port));
+  return value;
+}
+
+static inline unsigned short int
+intel_inw(unsigned short int port)
+{
+  unsigned short value;
+  asm volatile ("inw %w1, %0" : "=a" (value) : "Nd" (port));
+  return value;
+}
+
+static inline unsigned int
+intel_inl(unsigned short int port)
+{
+  u32 value;
+  asm volatile ("inl %w1, %0" : "=a" (value) : "Nd" (port));
+  return value;
+}
+
+static inline void
+intel_outb(unsigned char value, unsigned short int port)
+{
+  asm volatile ("outb %b0, %w1" : : "a" (value), "Nd" (port));
+}
+
+static inline void
+intel_outw(unsigned short int value, unsigned short int port)
+{
+  asm volatile ("outw %w0, %w1" : : "a" (value), "Nd" (port));
+}
+
+static inline void
+intel_outl(u32 value, unsigned short int port)
+{
+  asm volatile ("outl %0, %w1" : : "a" (value), "Nd" (port));
+}
+
+#elif defined(_MSC_VER)
+
+#pragma intrinsic(_outp)
+#pragma intrinsic(_outpw)
+#pragma intrinsic(_outpd)
+#pragma intrinsic(_inp)
+#pragma intrinsic(_inpw)
+#pragma intrinsic(_inpd)
+
+#define intel_outb(x, y) _outp(y, x)
+#define intel_outw(x, y) _outpw(y, x)
+#define intel_outl(x, y) _outpd(y, x)
+#define intel_inb(x) _inp(x)
+#define intel_inw(x) _inpw(x)
+#define intel_inl(x) _inpd(x)
+
+#else
+
+#error Do not know how to access I/O ports on this compiler
+
+#endif