| Chris Metcalf | 18aecc2 | 2011-05-04 14:38:26 -0400 | [diff] [blame] | 1 | /* | 
|  | 2 | * Copyright 2011 Tilera Corporation. All Rights Reserved. | 
|  | 3 | * | 
|  | 4 | *   This program is free software; you can redistribute it and/or | 
|  | 5 | *   modify it under the terms of the GNU General Public License | 
|  | 6 | *   as published by the Free Software Foundation, version 2. | 
|  | 7 | * | 
|  | 8 | *   This program is distributed in the hope that it will be useful, but | 
|  | 9 | *   WITHOUT ANY WARRANTY; without even the implied warranty of | 
|  | 10 | *   MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or | 
|  | 11 | *   NON INFRINGEMENT.  See the GNU General Public License for | 
|  | 12 | *   more details. | 
|  | 13 | * | 
|  | 14 | * This routine is a helper for migrating the home of a set of pages to | 
|  | 15 | * a new cpu.  See the documentation in homecache.c for more information. | 
|  | 16 | */ | 
|  | 17 |  | 
|  | 18 | #include <linux/linkage.h> | 
|  | 19 | #include <linux/threads.h> | 
|  | 20 | #include <asm/page.h> | 
|  | 21 | #include <asm/thread_info.h> | 
|  | 22 | #include <asm/types.h> | 
|  | 23 | #include <asm/asm-offsets.h> | 
|  | 24 | #include <hv/hypervisor.h> | 
|  | 25 |  | 
|  | 26 | .text | 
|  | 27 |  | 
|  | 28 | /* | 
|  | 29 | * First, some definitions that apply to all the code in the file. | 
|  | 30 | */ | 
|  | 31 |  | 
|  | 32 | /* Locals (caller-save) */ | 
|  | 33 | #define r_tmp		r10 | 
|  | 34 | #define r_save_sp	r11 | 
|  | 35 |  | 
|  | 36 | /* What we save where in the stack frame; must include all callee-saves. */ | 
|  | 37 | #define FRAME_SP	8 | 
|  | 38 | #define FRAME_R30	16 | 
|  | 39 | #define FRAME_R31	24 | 
|  | 40 | #define FRAME_R32	32 | 
|  | 41 | #define FRAME_R33	40 | 
|  | 42 | #define FRAME_SIZE	48 | 
|  | 43 |  | 
|  | 44 |  | 
|  | 45 |  | 
|  | 46 |  | 
|  | 47 | /* | 
|  | 48 | * On entry: | 
|  | 49 | * | 
|  | 50 | *   r0 the new context PA to install (moved to r_context) | 
|  | 51 | *   r1 PTE to use for context access (moved to r_access) | 
|  | 52 | *   r2 ASID to use for new context (moved to r_asid) | 
|  | 53 | *   r3 pointer to cpumask with just this cpu set in it (r_my_cpumask) | 
|  | 54 | */ | 
|  | 55 |  | 
|  | 56 | /* Arguments (caller-save) */ | 
|  | 57 | #define r_context_in	r0 | 
|  | 58 | #define r_access_in	r1 | 
|  | 59 | #define r_asid_in	r2 | 
|  | 60 | #define r_my_cpumask	r3 | 
|  | 61 |  | 
|  | 62 | /* Locals (callee-save); must not be more than FRAME_xxx above. */ | 
|  | 63 | #define r_save_ics	r30 | 
|  | 64 | #define r_context	r31 | 
|  | 65 | #define r_access	r32 | 
|  | 66 | #define r_asid		r33 | 
|  | 67 |  | 
|  | 68 | /* | 
|  | 69 | * Caller-save locals and frame constants are the same as | 
|  | 70 | * for homecache_migrate_stack_and_flush. | 
|  | 71 | */ | 
|  | 72 |  | 
|  | 73 | STD_ENTRY(flush_and_install_context) | 
|  | 74 | /* | 
|  | 75 | * Create a stack frame; we can't touch it once we flush the | 
|  | 76 | * cache until we install the new page table and flush the TLB. | 
|  | 77 | */ | 
|  | 78 | { | 
|  | 79 | move r_save_sp, sp | 
|  | 80 | st sp, lr | 
|  | 81 | addi sp, sp, -FRAME_SIZE | 
|  | 82 | } | 
|  | 83 | addi r_tmp, sp, FRAME_SP | 
|  | 84 | { | 
|  | 85 | st r_tmp, r_save_sp | 
|  | 86 | addi r_tmp, sp, FRAME_R30 | 
|  | 87 | } | 
|  | 88 | { | 
|  | 89 | st r_tmp, r30 | 
|  | 90 | addi r_tmp, sp, FRAME_R31 | 
|  | 91 | } | 
|  | 92 | { | 
|  | 93 | st r_tmp, r31 | 
|  | 94 | addi r_tmp, sp, FRAME_R32 | 
|  | 95 | } | 
|  | 96 | { | 
|  | 97 | st r_tmp, r32 | 
|  | 98 | addi r_tmp, sp, FRAME_R33 | 
|  | 99 | } | 
|  | 100 | st r_tmp, r33 | 
|  | 101 |  | 
|  | 102 | /* Move some arguments to callee-save registers. */ | 
|  | 103 | { | 
|  | 104 | move r_context, r_context_in | 
|  | 105 | move r_access, r_access_in | 
|  | 106 | } | 
|  | 107 | move r_asid, r_asid_in | 
|  | 108 |  | 
|  | 109 | /* Disable interrupts, since we can't use our stack. */ | 
|  | 110 | { | 
|  | 111 | mfspr r_save_ics, INTERRUPT_CRITICAL_SECTION | 
|  | 112 | movei r_tmp, 1 | 
|  | 113 | } | 
|  | 114 | mtspr INTERRUPT_CRITICAL_SECTION, r_tmp | 
|  | 115 |  | 
|  | 116 | /* First, flush our L2 cache. */ | 
|  | 117 | { | 
|  | 118 | move r0, zero  /* cache_pa */ | 
|  | 119 | moveli r1, hw2_last(HV_FLUSH_EVICT_L2)  /* cache_control */ | 
|  | 120 | } | 
|  | 121 | { | 
|  | 122 | shl16insli r1, r1, hw1(HV_FLUSH_EVICT_L2) | 
|  | 123 | move r2, r_my_cpumask  /* cache_cpumask */ | 
|  | 124 | } | 
|  | 125 | { | 
|  | 126 | shl16insli r1, r1, hw0(HV_FLUSH_EVICT_L2) | 
|  | 127 | move r3, zero  /* tlb_va */ | 
|  | 128 | } | 
|  | 129 | { | 
|  | 130 | move r4, zero  /* tlb_length */ | 
|  | 131 | move r5, zero  /* tlb_pgsize */ | 
|  | 132 | } | 
|  | 133 | { | 
|  | 134 | move r6, zero  /* tlb_cpumask */ | 
|  | 135 | move r7, zero  /* asids */ | 
|  | 136 | } | 
|  | 137 | { | 
|  | 138 | move r8, zero  /* asidcount */ | 
|  | 139 | jal hv_flush_remote | 
|  | 140 | } | 
|  | 141 | bnez r0, 1f | 
|  | 142 |  | 
|  | 143 | /* Now install the new page table. */ | 
|  | 144 | { | 
|  | 145 | move r0, r_context | 
|  | 146 | move r1, r_access | 
|  | 147 | } | 
|  | 148 | { | 
|  | 149 | move r2, r_asid | 
|  | 150 | movei r3, HV_CTX_DIRECTIO | 
|  | 151 | } | 
|  | 152 | jal hv_install_context | 
|  | 153 | bnez r0, 1f | 
|  | 154 |  | 
|  | 155 | /* Finally, flush the TLB. */ | 
|  | 156 | { | 
|  | 157 | movei r0, 0   /* preserve_global */ | 
|  | 158 | jal hv_flush_all | 
|  | 159 | } | 
|  | 160 |  | 
|  | 161 | 1:      /* Reset interrupts back how they were before. */ | 
|  | 162 | mtspr INTERRUPT_CRITICAL_SECTION, r_save_ics | 
|  | 163 |  | 
|  | 164 | /* Restore the callee-saved registers and return. */ | 
|  | 165 | addli lr, sp, FRAME_SIZE | 
|  | 166 | { | 
|  | 167 | ld lr, lr | 
|  | 168 | addli r_tmp, sp, FRAME_R30 | 
|  | 169 | } | 
|  | 170 | { | 
|  | 171 | ld r30, r_tmp | 
|  | 172 | addli r_tmp, sp, FRAME_R31 | 
|  | 173 | } | 
|  | 174 | { | 
|  | 175 | ld r31, r_tmp | 
|  | 176 | addli r_tmp, sp, FRAME_R32 | 
|  | 177 | } | 
|  | 178 | { | 
|  | 179 | ld r32, r_tmp | 
|  | 180 | addli r_tmp, sp, FRAME_R33 | 
|  | 181 | } | 
|  | 182 | { | 
|  | 183 | ld r33, r_tmp | 
|  | 184 | addi sp, sp, FRAME_SIZE | 
|  | 185 | } | 
|  | 186 | jrp lr | 
|  | 187 | STD_ENDPROC(flush_and_install_context) |