Large reorganization.

What was in core/ is now moved to arch/stm34l4xxx/peripherals.  This new
directory is *supposed to* to contain raw header files defining just the
pertinent register structures for the various peripherals.  Peripheral
management belongs somewhere in the new `kern/..` directories. This is
not completely the case at the moment, so more refactoring needs to be
done.

What was sitting in the root has now been moved into the kern/
directory. The kern/ directory is to contain everything else
other than raw device register definitions. The root of the kern/
tree is reserved for standard library-esque headers.

The kern/<peripheral> directory contains management systems for that
peripheral. (At the moment DMA is the only peripheral with a decent
management system.) Preferably these peripheral systems should only
include their correlating header in arch/stm34l4xxx/peripherals, and
use other management systems for handling other peripherals rather
than manipulating their raw registers directly. (Though this ideal
will require much more critical mass of management systems.)

1 files changed, 50 insertions, 0 deletions

diff --git a/02-usart/include/kern/common.h b/02-usart/include/kern/common.h
new file mode 100644
index 0000000..653279e
--- /dev/null
+++ b/02-usart/include/kern/common.h
@@ -0,0 +1,50 @@
+#ifndef COMMON__H
+#define COMMON__H
+
+#include <stdint.h>
+#include <stddef.h>
+#include <assert.h>
+
+#define WEAK __attribute__((weak))
+#define NORETURN __attribute__((noreturn))
+
+#ifndef static_assert
+#define static_assert(a, b)
+#endif
+
+/* Define __IO to be volatile if it's not already. */
+#ifndef __IO
+#define __IO volatile
+#endif
+
+#define CTZ(n) __builtin_ctz(n)
+
+#define bool int
+#ifndef __cplusplus
+#define true 1
+#define false 0
+#endif
+
+#define PACKED __attribute__((packed))
+#define BIT(n) (1 << (n))
+
+#define RESERVED_CONCAT_IMPL(x, y) x ## y
+#define RESERVED_MACRO_CONCAT(x, y) RESERVED_CONCAT_IMPL(x, y)
+#define RESERVED(n) \
+  bits_t RESERVED_MACRO_CONCAT(_r, __COUNTER__) :n
+  
+#define RESERVE(type) \
+  __IO type RESERVED_MACRO_CONCAT(_r, __COUNTER__)
+
+#define ptr2reg(ptr) \
+  ((uint32_t) (ptrdiff_t) (ptr))
+
+typedef __IO uint32_t bits_t;
+
+#define regset(reg, mask, val) \
+  ((reg) = ((reg) & ~mask) | (val << CTZ(mask)))
+
+#define regget(reg, mask) \
+  (((reg) & mask) >> (CTZ(mask)))
+
+#endif /* COMMON_H */