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gerrit.cesnet.cz / github / trini / u-boot / dbd6fcfbe2331b953784ba972f66cb3df3e50ab2 / . / arch / arm / mach-exynos / sec_boot.S
blob: dfc3455929ef1b716a562d129858898769a27cd4 [file] [log] [blame]
Akshay Saraswat67a06522015-02-20 13:27:15 +0530[diff] [blame]1/*
2 * Copyright (C) 2013 Samsung Electronics
3 * Akshay Saraswat <akshay.s@samsung.com>
4 *
5 * SPDX-License-Identifier: GPL-2.0+
6 */
7
8#include <config.h>
9#include <asm/arch/cpu.h>
10
11 .globl relocate_wait_code
12relocate_wait_code:
13 adr r0, code_base @ r0: source address (start)
14 adr r1, code_end @ r1: source address (end)
15 ldr r2, =0x02073000 @ r2: target address
161:
17 ldmia r0!, {r3-r6}
18 stmia r2!, {r3-r6}
19 cmp r0, r1
20 blt 1b
21 b code_end
22 .ltorg
23/*
24 * Secondary core waits here until Primary wake it up.
25 * Below code is copied to CONFIG_EXYNOS_RELOCATE_CODE_BASE.
26 * This is a workaround code which is supposed to act as a
27 * substitute/supplement to the iROM code.
28 *
29 * This workaround code is relocated to the address 0x02073000
30 * because that comes out to be the last 4KB of the iRAM
31 * (Base Address - 0x02020000, Limit Address - 0x020740000).
32 *
33 * U-boot and kernel are aware of this code and flags by the simple
34 * fact that we are implementing a workaround in the last 4KB
35 * of the iRAM and we have already defined these flag and address
36 * values in both kernel and U-boot for our use.
37 */
38code_base:
39 b 1f
40/*
41 * These addresses are being used as flags in u-boot and kernel.
42 *
43 * Jump address for resume and flag to check for resume/reset:
44 * Resume address - 0x2073008
45 * Resume flag - 0x207300C
46 *
47 * Jump address for cluster switching:
48 * Switch address - 0x2073018
49 *
50 * Jump address for core hotplug:
51 * Hotplug address - 0x207301C
52 *
53 * Jump address for C2 state (Reserved for future not being used right now):
54 * C2 address - 0x2073024
55 *
56 * Managed per core status for the active cluster:
57 * CPU0 state - 0x2073028
58 * CPU1 state - 0x207302C
59 * CPU2 state - 0x2073030
60 * CPU3 state - 0x2073034
61 *
62 * Managed per core GIC status for the active cluster:
63 * CPU0 gic state - 0x2073038
64 * CPU1 gic state - 0x207303C
65 * CPU2 gic state - 0x2073040
66 * CPU3 gic state - 0x2073044
67 *
68 * Logic of the code:
69 * Step-1: Read current CPU status.
70 * Step-2: If it's a resume then continue, else jump to step 4.
71 * Step-3: Clear inform1 PMU register and jump to inform0 value.
72 * Step-4: If it's a switch, C2 or reset, get the hotplug address.
73 * Step-5: If address is not available, enter WFE.
74 * Step-6: If address is available, jump to that address.
75 */
76 nop @ for backward compatibility
77 .word 0x0 @ REG0: RESUME_ADDR
78 .word 0x0 @ REG1: RESUME_FLAG
79 .word 0x0 @ REG2
80 .word 0x0 @ REG3
81_switch_addr:
82 .word 0x0 @ REG4: SWITCH_ADDR
83_hotplug_addr:
84 .word 0x0 @ REG5: CPU1_BOOT_REG
85 .word 0x0 @ REG6
86_c2_addr:
87 .word 0x0 @ REG7: REG_C2_ADDR
88_cpu_state:
89 .word 0x1 @ CPU0_STATE : RESET
90 .word 0x2 @ CPU1_STATE : SECONDARY RESET
91 .word 0x2 @ CPU2_STATE : SECONDARY RESET
92 .word 0x2 @ CPU3_STATE : SECONDARY RESET
93_gic_state:
94 .word 0x0 @ CPU0 - GICD_IGROUPR0
95 .word 0x0 @ CPU1 - GICD_IGROUPR0
96 .word 0x0 @ CPU2 - GICD_IGROUPR0
97 .word 0x0 @ CPU3 - GICD_IGROUPR0
981:
99 adr r0, _cpu_state
100 mrc p15, 0, r7, c0, c0, 5 @ read MPIDR
101 and r7, r7, #0xf @ r7 = cpu id
102/* Read the current cpu state */
103 ldr r10, [r0, r7, lsl #2]
104svc_entry:
105 tst r10, #(1 << 4)
106 adrne r0, _switch_addr
107 bne wait_for_addr
108/* Clear INFORM1 */
109 ldr r0, =(0x10040000 + 0x804)
110 ldr r1, [r0]
111 cmp r1, #0x0
112 movne r1, #0x0
113 strne r1, [r0]
114/* Get INFORM0 */
115 ldrne r1, =(0x10040000 + 0x800)
116 ldrne pc, [r1]
117 tst r10, #(1 << 0)
118 ldrne pc, =0x23e00000
119 adr r0, _hotplug_addr
120wait_for_addr:
121 ldr r1, [r0]
122 cmp r1, #0x0
123 bxne r1
124 wfe
125 b wait_for_addr
126 .ltorg
127code_end:
128 mov pc, lr