| Nicolas Pitre | e8db288 | 2012-04-12 02:45:22 -0400 | [diff] [blame^] | 1 | /* |
| 2 | * arch/arm/common/mcpm_head.S -- kernel entry point for multi-cluster PM |
| 3 | * |
| 4 | * Created by: Nicolas Pitre, March 2012 |
| 5 | * Copyright: (C) 2012-2013 Linaro Limited |
| 6 | * |
| 7 | * This program is free software; you can redistribute it and/or modify |
| 8 | * it under the terms of the GNU General Public License version 2 as |
| 9 | * published by the Free Software Foundation. |
| 10 | */ |
| 11 | |
| 12 | #include <linux/linkage.h> |
| 13 | #include <asm/mcpm.h> |
| 14 | |
| 15 | .macro pr_dbg string |
| 16 | #if defined(CONFIG_DEBUG_LL) && defined(DEBUG) |
| 17 | b 1901f |
| 18 | 1902: .asciz "CPU" |
| 19 | 1903: .asciz " cluster" |
| 20 | 1904: .asciz ": \string" |
| 21 | .align |
| 22 | 1901: adr r0, 1902b |
| 23 | bl printascii |
| 24 | mov r0, r9 |
| 25 | bl printhex8 |
| 26 | adr r0, 1903b |
| 27 | bl printascii |
| 28 | mov r0, r10 |
| 29 | bl printhex8 |
| 30 | adr r0, 1904b |
| 31 | bl printascii |
| 32 | #endif |
| 33 | .endm |
| 34 | |
| 35 | .arm |
| 36 | .align |
| 37 | |
| 38 | ENTRY(mcpm_entry_point) |
| 39 | |
| 40 | THUMB( adr r12, BSYM(1f) ) |
| 41 | THUMB( bx r12 ) |
| 42 | THUMB( .thumb ) |
| 43 | 1: |
| 44 | mrc p15, 0, r0, c0, c0, 5 @ MPIDR |
| 45 | ubfx r9, r0, #0, #8 @ r9 = cpu |
| 46 | ubfx r10, r0, #8, #8 @ r10 = cluster |
| 47 | mov r3, #MAX_CPUS_PER_CLUSTER |
| 48 | mla r4, r3, r10, r9 @ r4 = canonical CPU index |
| 49 | cmp r4, #(MAX_CPUS_PER_CLUSTER * MAX_NR_CLUSTERS) |
| 50 | blo 2f |
| 51 | |
| 52 | /* We didn't expect this CPU. Try to cheaply make it quiet. */ |
| 53 | 1: wfi |
| 54 | wfe |
| 55 | b 1b |
| 56 | |
| 57 | 2: pr_dbg "kernel mcpm_entry_point\n" |
| 58 | |
| 59 | /* |
| 60 | * MMU is off so we need to get to mcpm_entry_vectors in a |
| 61 | * position independent way. |
| 62 | */ |
| 63 | adr r5, 3f |
| 64 | ldr r6, [r5] |
| 65 | add r6, r5, r6 @ r6 = mcpm_entry_vectors |
| 66 | |
| 67 | mcpm_entry_gated: |
| 68 | ldr r5, [r6, r4, lsl #2] @ r5 = CPU entry vector |
| 69 | cmp r5, #0 |
| 70 | wfeeq |
| 71 | beq mcpm_entry_gated |
| 72 | pr_dbg "released\n" |
| 73 | bx r5 |
| 74 | |
| 75 | .align 2 |
| 76 | |
| 77 | 3: .word mcpm_entry_vectors - . |
| 78 | |
| 79 | ENDPROC(mcpm_entry_point) |
| 80 | |
| 81 | .bss |
| 82 | .align 5 |
| 83 | |
| 84 | .type mcpm_entry_vectors, #object |
| 85 | ENTRY(mcpm_entry_vectors) |
| 86 | .space 4 * MAX_NR_CLUSTERS * MAX_CPUS_PER_CLUSTER |