shim: Rework pause functions and add read_counter()

Signed-off-by: Peter Jones <pjones@redhat.com>
Upstream-commit-id: fc6b0bca84e

include/asm.h

@@ -0,0 +1,59 @@
+/*
+ * asm.h
+ * Copyright 2018 Peter Jones <pjones@redhat.com>
+ */
+
+#ifndef SHIM_ASM_H_
+#define SHIM_ASM_H_
+
+#define __stringify_1(x...)     #x
+#define __stringify(x...)       __stringify_1(x)
+
+static inline uint64_t read_counter(void)
+{
+        uint64_t val;
+#if defined (__x86_64__)
+        unsigned long low, high;
+        __asm__ __volatile__("rdtsc" : "=a" (low), "=d" (high));
+        val = (low) | (high) << 32;
+#elif defined(__i386__) || defined(__i686__)
+        __asm__ __volatile__("rdtsc" : "=A" (val));
+#elif defined(__aarch64__)
+        __asm__ __volatile__ ("mrs %0, pmccntr_el0" : "=r" (val));
+#elif defined(__arm__)
+        __asm__ __volatile__ ("mrc p15, 0, %0, c9, c13, 0" : "=r" (val));
+#else
+#error unsupported arch
+#endif
+        return val;
+}
+
+#if defined(__x86_64__) || defined(__i386__) || defined(__i686__)
+static inline void pause(void)
+{
+	__asm__ __volatile__("pause");
+}
+#elif defined(__aarch64__)
+static inline void pause(void)
+{
+		__asm__ __volatile__("wfi");
+}
+#else
+static inline void pause(void)
+{
+        uint64_t a, b;
+        int x;
+        extern void msleep(unsigned long msecs);
+
+        a = read_counter();
+        for (x = 0; x < 1000; x++) {
+                msleep(1000);
+                b = read_counter();
+                if (a != b)
+                        break;
+        }
+}
+#endif
+
+#endif /* !SHIM_ASM_H_ */
+// vim:fenc=utf-8:tw=75:et

include/compiler.h

@@ -0,0 +1,156 @@
+/*
+ * compiler.h
+ * Copyright 2019 Peter Jones <pjones@redhat.com>
+ */
+
+#ifndef COMPILER_H_
+#define COMPILER_H_
+
+#ifndef UNUSED
+#define UNUSED __attribute__((__unused__))
+#endif
+#ifndef HIDDEN
+#define HIDDEN __attribute__((__visibility__ ("hidden")))
+#endif
+#ifndef PUBLIC
+#define PUBLIC __attribute__((__visibility__ ("default")))
+#endif
+#ifndef DESTRUCTOR
+#define DESTRUCTOR __attribute__((destructor))
+#endif
+#ifndef CONSTRUCTOR
+#define CONSTRUCTOR __attribute__((constructor))
+#endif
+#ifndef ALIAS
+#define ALIAS(x) __attribute__((weak, alias (#x)))
+#endif
+#ifndef NONNULL
+#endif
+#define NONNULL(first, args...) __attribute__((__nonnull__(first, ## args)))
+#ifndef PRINTF
+#define PRINTF(first, args...) __attribute__((__format__(printf, first, ## args)))
+#endif
+#ifndef FLATTEN
+#define FLATTEN __attribute__((__flatten__))
+#endif
+#ifndef PACKED
+#define PACKED __attribute__((__packed__))
+#endif
+#ifndef VERSION
+#define VERSION(sym, ver) __asm__(".symver " # sym "," # ver)
+#endif
+#ifndef NORETURN
+#define NORETURN __attribute__((__noreturn__))
+#endif
+#ifndef ALIGNED
+#define ALIGNED(n) __attribute__((__aligned__(n)))
+#endif
+#ifndef CLEANUP_FUNC
+#define CLEANUP_FUNC(x) __attribute__((__cleanup__(x)))
+#endif
+#ifndef USED
+#define USED __attribute__((__used__))
+#endif
+#ifndef SECTION
+#define SECTION(x) __attribute__((__section__(x)))
+#endif
+#ifndef OPTIMIZE
+#define OPTIMIZE(x) __attribute__((__optimize__(x)))
+#endif
+
+#ifndef __CONCAT
+#define __CONCAT3(a, b, c) a ## b ## c
+#endif
+#ifndef CAT
+#define CAT(a, b) __CONCAT(a, b)
+#endif
+#ifndef CAT3
+#define CAT3(a, b, c) __CONCAT3(a, b, c)
+#endif
+#ifndef STRING
+#define STRING(x) __STRING(x)
+#endif
+
+#ifndef WRITE_ONCE
+#define WRITE_ONCE(var, val) \
+        (*((volatile typeof(val) *)(&(var))) = (val))
+#endif
+
+#ifndef READ_ONCE
+#define READ_ONCE(var) (*((volatile typeof(var) *)(&(var))))
+#endif
+
+#ifndef likely
+#define likely(x)	__builtin_expect(!!(x), 1)
+#endif
+
+#ifndef unlikely
+#define unlikely(x)	__builtin_expect(!!(x), 0)
+#endif
+
+/* Are two types/vars the same type (ignoring qualifiers)? */
+#ifndef __same_type
+#define __same_type(a, b) __builtin_types_compatible_p(typeof(a), typeof(b))
+#endif
+
+/* Compile time object size, -1 for unknown */
+#ifndef __compiletime_object_size
+# define __compiletime_object_size(obj) -1
+#endif
+#ifndef __compiletime_warning
+# define __compiletime_warning(message)
+#endif
+#ifndef __compiletime_error
+# define __compiletime_error(message)
+#endif
+
+#ifndef __compiletime_assert
+#define __compiletime_assert(condition, msg, prefix, suffix)		\
+	do {								\
+		extern void prefix ## suffix(void) __compiletime_error(msg); \
+		if (!(condition))					\
+			prefix ## suffix();				\
+	} while (0)
+#endif
+
+#ifndef _compiletime_assert
+#define _compiletime_assert(condition, msg, prefix, suffix) \
+	__compiletime_assert(condition, msg, prefix, suffix)
+#endif
+
+/**
+ * compiletime_assert - break build and emit msg if condition is false
+ * @condition: a compile-time constant condition to check
+ * @msg:       a message to emit if condition is false
+ *
+ * In tradition of POSIX assert, this macro will break the build if the
+ * supplied condition is *false*, emitting the supplied error message if the
+ * compiler has support to do so.
+ */
+#ifndef compiletime_assert
+#define compiletime_assert(condition, msg) \
+	_compiletime_assert(condition, msg, __compiletime_assert_, __LINE__)
+#endif
+
+/**
+ * BUILD_BUG_ON_MSG - break compile if a condition is true & emit supplied
+ *		      error message.
+ * @condition: the condition which the compiler should know is false.
+ *
+ * See BUILD_BUG_ON for description.
+ */
+#ifndef BUILD_BUG_ON_MSG
+#define BUILD_BUG_ON_MSG(cond, msg) compiletime_assert(!(cond), msg)
+#endif
+
+#ifndef ALIGN
+#define __ALIGN_MASK(x, mask)   (((x) + (mask)) & ~(mask))
+#define __ALIGN(x, a)           __ALIGN_MASK(x, (typeof(x))(a) - 1)
+#define ALIGN(x, a)             __ALIGN((x), (a))
+#endif
+#ifndef ALIGN_DOWN
+#define ALIGN_DOWN(x, a)        __ALIGN((x) - ((a) - 1), (a))
+#endif
+
+#endif /* !COMPILER_H_ */
+// vim:fenc=utf-8:tw=75:et

shim.c

@@ -2543,16 +2543,14 @@ debug_hook(void)
 #if defined(__x86_64__) || defined(__i386__) || defined(__i686__)
 		if (x > 4294967294ULL)
 			break;
-		__asm__ __volatile__("pause");
 #elif defined(__aarch64__)
 		if (x > 1000)
 			break;
-		__asm__ __volatile__("wfi");
 #else
 		if (x > 12000)
 			break;
-		msleep(5000);
 #endif
+		pause();
 	}
 	x = 1;
 }

shim.h

@@ -97,6 +97,7 @@
 #define FALLBACK L"\\fb" EFI_ARCH L".efi"
 #define MOK_MANAGER L"\\mm" EFI_ARCH L".efi"
 
+#include "include/asm.h"
 #include "include/configtable.h"
 #include "include/console.h"
 #include "include/crypt_blowfish.h"