1 /**
2  * \file
3  * \brief Utilities, amd64 version
4  */
5 /*
6  * (c) 2008-2009 Adam Lackorzynski <adam@os.inf.tu-dresden.de>,
7  *               Alexander Warg <warg@os.inf.tu-dresden.de>,
8  *               Torsten Frenzel <frenzel@os.inf.tu-dresden.de>
9  *     economic rights: Technische Universität Dresden (Germany)
10  * This file is part of TUD:OS and distributed under the terms of the
11  * GNU Lesser General Public License 2.1.
12  * Please see the COPYING-LGPL-2.1 file for details.
13  */
14 #ifndef __UTIL_H
15 #define __UTIL_H
16 
17 #include <l4/sys/types.h>
18 #include <l4/sys/compiler.h>
19 #include <l4/sys/ipc.h>
20 
21 EXTERN_C_BEGIN
22 
23 /** Calculate l4 timeouts
24  * \param mus	time in microseconds. Special cases:
25  *		- 0 - > timeout 0
26  *		- ~0U -> timeout NEVER
27  * \return the corresponding l4_timeout value
28  */
29 L4_CV l4_timeout_s l4util_micros2l4to(unsigned int mus) L4_NOTHROW;
30 
31 /** Suspend thread for a period of \a ms milliseconds
32  * \param ms Time in milliseconds
33  */
34 L4_CV void l4_sleep(int ms) L4_NOTHROW;
35 
36 /* Suspend thread for a period of \a us microseconds.
37  * \param us Time in microseconds
38  * WARNING: This function is mostly bogus since the timer resolution of
39  *          current L4 implementations is about 1ms! */
40 L4_CV void l4_usleep(int us) L4_NOTHROW;
41 
42 /**
43  * \brief Go sleep and never wake up.
44  * \ingroup l4util_api
45  *
46  */
47 L4_INLINE void l4_sleep_forever(void) L4_NOTHROW __attribute__((noreturn));
48 
49 L4_INLINE void
l4_sleep_forever(void)50 l4_sleep_forever(void) L4_NOTHROW
51 {
52   for (;;)
53     l4_ipc_sleep(L4_IPC_NEVER);
54 }
55 
56 /** Touch data areas to force mapping read-only */
57 static inline void
l4_touch_ro(const void * addr,unsigned size)58 l4_touch_ro(const void*addr, unsigned size) L4_NOTHROW
59 {
60   const char *bptr, *eptr;
61 
62   bptr = (const char*)(((l4_addr_t)addr) & L4_PAGEMASK);
63   eptr = (const char*)(((l4_addr_t)addr+size-1) & L4_PAGEMASK);
64   for(;bptr<=eptr;bptr+=L4_PAGESIZE){
65     asm volatile("or	%0,%%rax \n"
66                  :
67                  : "m" (*(const unsigned*)bptr)
68                  : "rax" );
69   }
70 }
71 
72 
73 /** Touch data areas to force mapping read-write */
74 static inline void
l4_touch_rw(const void * addr,unsigned size)75 l4_touch_rw(const void*addr, unsigned size) L4_NOTHROW
76 {
77   const char *bptr, *eptr;
78 
79   bptr = (const char*)(((l4_addr_t)addr) & L4_PAGEMASK);
80   eptr = (const char*)(((l4_addr_t)addr+size-1) & L4_PAGEMASK);
81   for(;bptr<=eptr;bptr+=L4_PAGESIZE){
82     asm volatile("orb	$0,%0 \n"
83                  :
84                  : "m" (*(const unsigned*)bptr)
85                  );
86   }
87 }
88 
89 EXTERN_C_END
90 
91 #endif
92 
93