1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
|
/*
* Copyright (c) 2014-2023, Arm Limited and Contributors. All rights reserved.
*
* SPDX-License-Identifier: BSD-3-Clause
*/
#include <asm_macros.S>
#include <assert_macros.S>
#include <lib/psci/psci.h>
#include <platform_def.h>
.globl psci_do_pwrdown_cache_maintenance
.globl psci_do_pwrup_cache_maintenance
.globl psci_power_down_wfi
/* -----------------------------------------------------------------------
* void psci_do_pwrdown_cache_maintenance(unsigned int power level);
*
* This function performs cache maintenance for the specified power
* level. The levels of cache affected are determined by the power
* level which is passed as the argument i.e. level 0 results
* in a flush of the L1 cache. Both the L1 and L2 caches are flushed
* for a higher power level.
*
* Additionally, this function also ensures that stack memory is correctly
* flushed out to avoid coherency issues due to a change in its memory
* attributes after the data cache is disabled.
* -----------------------------------------------------------------------
*/
func psci_do_pwrdown_cache_maintenance
stp x29, x30, [sp,#-16]!
stp x19, x20, [sp,#-16]!
/* ---------------------------------------------
* Invoke CPU-specific power down operations for
* the appropriate level
* ---------------------------------------------
*/
bl prepare_cpu_pwr_dwn
/* ---------------------------------------------
* Do stack maintenance by flushing the used
* stack to the main memory and invalidating the
* remainder.
* ---------------------------------------------
*/
bl plat_get_my_stack
/* ---------------------------------------------
* Calculate and store the size of the used
* stack memory in x1.
* ---------------------------------------------
*/
mov x19, x0
mov x1, sp
sub x1, x0, x1
mov x0, sp
bl flush_dcache_range
/* ---------------------------------------------
* Calculate and store the size of the unused
* stack memory in x1. Calculate and store the
* stack base address in x0.
* ---------------------------------------------
*/
sub x0, x19, #PLATFORM_STACK_SIZE
sub x1, sp, x0
bl inv_dcache_range
ldp x19, x20, [sp], #16
ldp x29, x30, [sp], #16
ret
endfunc psci_do_pwrdown_cache_maintenance
/* -----------------------------------------------------------------------
* void psci_do_pwrup_cache_maintenance(void);
*
* This function performs cache maintenance after this cpu is powered up.
* Currently, this involves managing the used stack memory before turning
* on the data cache.
* -----------------------------------------------------------------------
*/
func psci_do_pwrup_cache_maintenance
stp x29, x30, [sp,#-16]!
/* ---------------------------------------------
* Ensure any inflight stack writes have made it
* to main memory.
* ---------------------------------------------
*/
dmb st
/* ---------------------------------------------
* Calculate and store the size of the used
* stack memory in x1. Calculate and store the
* stack base address in x0.
* ---------------------------------------------
*/
bl plat_get_my_stack
mov x1, sp
sub x1, x0, x1
mov x0, sp
bl inv_dcache_range
/* ---------------------------------------------
* Enable the data cache.
* ---------------------------------------------
*/
mrs x0, sctlr_el3
orr x0, x0, #SCTLR_C_BIT
msr sctlr_el3, x0
isb
ldp x29, x30, [sp], #16
ret
endfunc psci_do_pwrup_cache_maintenance
/* -----------------------------------------------------------------------
* void psci_power_down_wfi(void);
* This function is called to indicate to the power controller that it
* is safe to power down this cpu. It should not exit the wfi and will
* be released from reset upon power up.
* -----------------------------------------------------------------------
*/
func psci_power_down_wfi
#if ERRATA_A510_2684597
bl apply_cpu_pwr_dwn_errata
#endif
dsb sy // ensure write buffer empty
1:
wfi
b 1b
endfunc psci_power_down_wfi
|
