diff options
Diffstat (limited to 'arch/arm/mach-tegra/sleep-t30.S')
-rw-r--r-- | arch/arm/mach-tegra/sleep-t30.S | 107 |
1 files changed, 107 insertions, 0 deletions
diff --git a/arch/arm/mach-tegra/sleep-t30.S b/arch/arm/mach-tegra/sleep-t30.S new file mode 100644 index 000000000000..777d9cee8b90 --- /dev/null +++ b/arch/arm/mach-tegra/sleep-t30.S | |||
@@ -0,0 +1,107 @@ | |||
1 | /* | ||
2 | * Copyright (c) 2012, NVIDIA Corporation. All rights reserved. | ||
3 | * | ||
4 | * This program is free software; you can redistribute it and/or modify it | ||
5 | * under the terms and conditions of the GNU General Public License, | ||
6 | * version 2, as published by the Free Software Foundation. | ||
7 | * | ||
8 | * This program is distributed in the hope it will be useful, but WITHOUT | ||
9 | * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or | ||
10 | * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for | ||
11 | * more details. | ||
12 | * | ||
13 | * You should have received a copy of the GNU General Public License | ||
14 | * along with this program. If not, see <http://www.gnu.org/licenses/>. | ||
15 | */ | ||
16 | |||
17 | #include <linux/linkage.h> | ||
18 | |||
19 | #include <asm/assembler.h> | ||
20 | |||
21 | #include <mach/iomap.h> | ||
22 | |||
23 | #include "sleep.h" | ||
24 | #include "flowctrl.h" | ||
25 | |||
26 | #define TEGRA30_POWER_HOTPLUG_SHUTDOWN (1 << 27) /* Hotplug shutdown */ | ||
27 | |||
28 | #if defined(CONFIG_HOTPLUG_CPU) || defined(CONFIG_PM_SLEEP) | ||
29 | /* | ||
30 | * tegra30_hotplug_shutdown(void) | ||
31 | * | ||
32 | * Powergates the current CPU. | ||
33 | * Should never return. | ||
34 | */ | ||
35 | ENTRY(tegra30_hotplug_shutdown) | ||
36 | /* Turn off SMP coherency */ | ||
37 | exit_smp r4, r5 | ||
38 | |||
39 | /* Powergate this CPU */ | ||
40 | mov r0, #TEGRA30_POWER_HOTPLUG_SHUTDOWN | ||
41 | bl tegra30_cpu_shutdown | ||
42 | mov pc, lr @ should never get here | ||
43 | ENDPROC(tegra30_hotplug_shutdown) | ||
44 | |||
45 | /* | ||
46 | * tegra30_cpu_shutdown(unsigned long flags) | ||
47 | * | ||
48 | * Puts the current CPU in wait-for-event mode on the flow controller | ||
49 | * and powergates it -- flags (in R0) indicate the request type. | ||
50 | * Must never be called for CPU 0. | ||
51 | * | ||
52 | * corrupts r0-r4, r12 | ||
53 | */ | ||
54 | ENTRY(tegra30_cpu_shutdown) | ||
55 | cpu_id r3 | ||
56 | cmp r3, #0 | ||
57 | moveq pc, lr @ Must never be called for CPU 0 | ||
58 | |||
59 | ldr r12, =TEGRA_FLOW_CTRL_VIRT | ||
60 | cpu_to_csr_reg r1, r3 | ||
61 | add r1, r1, r12 @ virtual CSR address for this CPU | ||
62 | cpu_to_halt_reg r2, r3 | ||
63 | add r2, r2, r12 @ virtual HALT_EVENTS address for this CPU | ||
64 | |||
65 | /* | ||
66 | * Clear this CPU's "event" and "interrupt" flags and power gate | ||
67 | * it when halting but not before it is in the "WFE" state. | ||
68 | */ | ||
69 | movw r12, \ | ||
70 | FLOW_CTRL_CSR_INTR_FLAG | FLOW_CTRL_CSR_EVENT_FLAG | \ | ||
71 | FLOW_CTRL_CSR_ENABLE | ||
72 | mov r4, #(1 << 4) | ||
73 | orr r12, r12, r4, lsl r3 | ||
74 | str r12, [r1] | ||
75 | |||
76 | /* Halt this CPU. */ | ||
77 | mov r3, #0x400 | ||
78 | delay_1: | ||
79 | subs r3, r3, #1 @ delay as a part of wfe war. | ||
80 | bge delay_1; | ||
81 | cpsid a @ disable imprecise aborts. | ||
82 | ldr r3, [r1] @ read CSR | ||
83 | str r3, [r1] @ clear CSR | ||
84 | tst r0, #TEGRA30_POWER_HOTPLUG_SHUTDOWN | ||
85 | movne r3, #FLOW_CTRL_WAITEVENT @ For hotplug | ||
86 | str r3, [r2] | ||
87 | ldr r0, [r2] | ||
88 | b wfe_war | ||
89 | |||
90 | __cpu_reset_again: | ||
91 | dsb | ||
92 | .align 5 | ||
93 | wfe @ CPU should be power gated here | ||
94 | wfe_war: | ||
95 | b __cpu_reset_again | ||
96 | |||
97 | /* | ||
98 | * 38 nop's, which fills reset of wfe cache line and | ||
99 | * 4 more cachelines with nop | ||
100 | */ | ||
101 | .rept 38 | ||
102 | nop | ||
103 | .endr | ||
104 | b . @ should never get here | ||
105 | |||
106 | ENDPROC(tegra30_cpu_shutdown) | ||
107 | #endif | ||