1 /*
2  * Copyright (c) 2008 Travis Geiselbrecht
3  *
4  * Permission is hereby granted, free of charge, to any person obtaining
5  * a copy of this software and associated documentation files
6  * (the "Software"), to deal in the Software without restriction,
7  * including without limitation the rights to use, copy, modify, merge,
8  * publish, distribute, sublicense, and/or sell copies of the Software,
9  * and to permit persons to whom the Software is furnished to do so,
10  * subject to the following conditions:
11  *
12  * The above copyright notice and this permission notice shall be
13  * included in all copies or substantial portions of the Software.
14  *
15  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
16  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
17  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
18  * IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
19  * CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
20  * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
21  * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
22  */
23 #ifndef __PLATFORM_H
24 #define __PLATFORM_H
25 
26 #include <sys/types.h>
27 #include <compiler.h>
28 
29 __BEGIN_CDECLS;
30 
31 typedef enum {
32     HALT_ACTION_HALT = 0,       // Spin forever.
33     HALT_ACTION_REBOOT,         // Reset the CPU.
34     HALT_ACTION_SHUTDOWN,       // Shutdown and power off.
35 } platform_halt_action;
36 
37 typedef enum {
38     HALT_REASON_UNKNOWN = 0,
39     HALT_REASON_POR,            // Cold-boot
40     HALT_REASON_HW_WATCHDOG,    // HW watchdog timer
41     HALT_REASON_LOWVOLTAGE,     // LV/Brownout condition
42     HALT_REASON_HIGHVOLTAGE,    // High voltage condition.
43     HALT_REASON_THERMAL,        // Thermal reason (probably overtemp)
44     HALT_REASON_OTHER_HW,       // Other hardware (platform) specific reason
45     HALT_REASON_SW_RESET,       // Generic Software Initiated Reboot
46     HALT_REASON_SW_WATCHDOG,    // Reboot triggered by a SW watchdog timer
47     HALT_REASON_SW_PANIC,       // Reboot triggered by a SW panic or ASSERT
48     HALT_REASON_SW_UPDATE,      // SW triggered reboot in order to begin firmware update
49 } platform_halt_reason;
50 
51 lk_time_t current_time(void);
52 lk_time_ns_t current_time_ns(void);
53 
54 /* super early platform initialization, before almost everything */
55 void platform_early_init(void);
56 
57 /* later init, after the kernel has come up */
58 void platform_init(void);
59 
60 /* called by the arch init code to get the platform to set up any mmu mappings it may need */
61 void platform_init_mmu_mappings(void);
62 
63 /* if the platform has knowledge of what caused the latest reboot, it can report
64  * it to applications with this function.  */
65 platform_halt_reason platform_get_reboot_reason(void);
66 
67 /* platform_halt is a method which is called from various places in the LK
68  * system, and may be implemented by platforms and called by applications.  This
69  * call represents the end of the life of SW for a device; there is no returning
70  * from this function.  Callers will provide a reason for the halt, and a
71  * suggested action for the platform to take, but it is the platform's
72  * responsibility to determine the final action taken.  For example, in the case
73  * of a failed ASSERT or a panic, LK will call platform halt and suggest a Halt
74  * action, but a release build on a platform with no debug channel may choose to
75  * reboot instead as there is no one to tell about the ASSERT, and no one
76  * waiting to debug the device in its halted state.  If not overloaded by the
77  * platform, the default behavior of platform halt will be to dprintf the
78  * reason, and then halt execution by turning off interrupts and spinning
79  * forever.
80  */
81 void platform_halt(platform_halt_action suggested_action,
82                    platform_halt_reason reason) __NO_RETURN;
83 
84 /* called during chain loading to make sure drivers and platform is put into a stopped state */
85 void platform_quiesce(void);
86 
87 /* called by LK idle thread to enter idle state. It is declared as WEAK
88  * (the default implementation is just calling arch_idle) and can be overridden
89  * by platform to implement platform specific handling.
90  */
91 void platform_idle(void);
92 
93 /* platform_early_halt is a simpler version of platform_halt() that can be
94  * called from any context, including early init and assembly with no stack.
95  */
96 void platform_early_halt(void) __NO_RETURN;
97 
98 /* called by LK thread_resched() and other functions in 'thread.c'.
99  * The purpose of this API is to set info in shared memory whenever the
100  * priority on a CPU changes. Such changes can occur when the current
101  * thread priority changes, or the scheduler switches to another
102  * thread, or when an IPI is sent to another CPU.
103  */
104 void platform_cpu_priority_set(uint32_t cpu_nr, uint32_t priority);
105 
106 __END_CDECLS;
107 
108 #endif
109