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
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
|
/*
* Copyright (c) 2016, ARM Limited and Contributors. All rights reserved.
*
* SPDX-License-Identifier: BSD-3-Clause
*/
#include <arch_helpers.h>
#include <assert.h>
#include <css_pm.h>
#include <debug.h>
#include <plat_arm.h>
#include "../scpi/css_scpi.h"
#include "css_scp.h"
/*
* This file implements the SCP power management functions using SCPI protocol.
*/
/*
* Helper function to inform power down state to SCP.
*/
void css_scp_suspend(const psci_power_state_t *target_state)
{
uint32_t cluster_state = scpi_power_on;
uint32_t system_state = scpi_power_on;
/* Check if power down at system power domain level is requested */
if (CSS_SYSTEM_PWR_STATE(target_state) == ARM_LOCAL_STATE_OFF)
system_state = scpi_power_retention;
/* Cluster is to be turned off, so disable coherency */
if (CSS_CLUSTER_PWR_STATE(target_state) == ARM_LOCAL_STATE_OFF)
cluster_state = scpi_power_off;
/*
* Ask the SCP to power down the appropriate components depending upon
* their state.
*/
scpi_set_css_power_state(read_mpidr_el1(),
scpi_power_off,
cluster_state,
system_state);
}
/*
* Helper function to turn off a CPU power domain and its parent power domains
* if applicable. Since SCPI doesn't differentiate between OFF and suspend, we
* call the suspend helper here.
*/
void css_scp_off(const psci_power_state_t *target_state)
{
css_scp_suspend(target_state);
}
/*
* Helper function to turn ON a CPU power domain and its parent power domains
* if applicable.
*/
void css_scp_on(u_register_t mpidr)
{
/*
* SCP takes care of powering up parent power domains so we
* only need to care about level 0
*/
scpi_set_css_power_state(mpidr, scpi_power_on, scpi_power_on,
scpi_power_on);
}
/*
* Helper function to get the power state of a power domain node as reported
* by the SCP.
*/
int css_scp_get_power_state(u_register_t mpidr, unsigned int power_level)
{
int rc, element;
unsigned int cpu_state, cluster_state;
/*
* The format of 'power_level' is implementation-defined, but 0 must
* mean a CPU. We also allow 1 to denote the cluster
*/
if (power_level != ARM_PWR_LVL0 && power_level != ARM_PWR_LVL1)
return PSCI_E_INVALID_PARAMS;
/* Query SCP */
rc = scpi_get_css_power_state(mpidr, &cpu_state, &cluster_state);
if (rc != 0)
return PSCI_E_INVALID_PARAMS;
/* Map power states of CPU and cluster to expected PSCI return codes */
if (power_level == ARM_PWR_LVL0) {
/*
* The CPU state returned by SCP is an 8-bit bit mask
* corresponding to each CPU in the cluster
*/
#if ARM_PLAT_MT
/*
* The current SCPI driver only caters for single-threaded
* platforms. Hence we ignore the thread ID (which is always 0)
* for such platforms.
*/
element = (mpidr >> MPIDR_AFF1_SHIFT) & MPIDR_AFFLVL_MASK;
#else
element = mpidr & MPIDR_AFFLVL_MASK;
#endif /* ARM_PLAT_MT */
return CSS_CPU_PWR_STATE(cpu_state, element) ==
CSS_CPU_PWR_STATE_ON ? HW_ON : HW_OFF;
} else {
assert(cluster_state == CSS_CLUSTER_PWR_STATE_ON ||
cluster_state == CSS_CLUSTER_PWR_STATE_OFF);
return cluster_state == CSS_CLUSTER_PWR_STATE_ON ? HW_ON :
HW_OFF;
}
}
/*
* Helper function to shutdown the system via SCPI.
*/
void __dead2 css_scp_sys_shutdown(void)
{
uint32_t response;
/*
* Disable GIC CPU interface to prevent pending interrupt
* from waking up the AP from WFI.
*/
plat_arm_gic_cpuif_disable();
/* Send the power down request to the SCP */
response = scpi_sys_power_state(scpi_system_shutdown);
if (response != SCP_OK) {
ERROR("CSS System Off: SCP error %u.\n", response);
panic();
}
wfi();
ERROR("CSS System Off: operation not handled.\n");
panic();
}
/*
* Helper function to reset the system via SCPI.
*/
void __dead2 css_scp_sys_reboot(void)
{
uint32_t response;
/*
* Disable GIC CPU interface to prevent pending interrupt
* from waking up the AP from WFI.
*/
plat_arm_gic_cpuif_disable();
/* Send the system reset request to the SCP */
response = scpi_sys_power_state(scpi_system_reboot);
if (response != SCP_OK) {
ERROR("CSS System Reset: SCP error %u.\n", response);
panic();
}
wfi();
ERROR("CSS System Reset: operation not handled.\n");
panic();
}
|
