diff options
author | Achin Gupta <achin.gupta@arm.com> | 2013-10-25 09:08:21 +0100 |
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committer | James Morrissey <james.morrissey@arm.com> | 2013-10-25 09:37:16 +0100 |
commit | 4f6ad66ae9fcc8bcb3b0fcee10b7ab1ffcaf1a56 (patch) | |
tree | 475db5d74370cb62b02afab0900774955a59702f /lib/sync | |
download | arm-trusted-firmware-4f6ad66ae9fcc8bcb3b0fcee10b7ab1ffcaf1a56.tar.gz |
ARMv8 Trusted Firmware release v0.2v0.2
Diffstat (limited to 'lib/sync')
-rw-r--r-- | lib/sync/locks/bakery/bakery_lock.c | 104 | ||||
-rw-r--r-- | lib/sync/locks/exclusive/spinlock.S | 50 |
2 files changed, 154 insertions, 0 deletions
diff --git a/lib/sync/locks/bakery/bakery_lock.c b/lib/sync/locks/bakery/bakery_lock.c new file mode 100644 index 0000000..d3c780c --- /dev/null +++ b/lib/sync/locks/bakery/bakery_lock.c @@ -0,0 +1,104 @@ +/* + * Copyright (c) 2013, ARM Limited. All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions are met: + * + * Redistributions of source code must retain the above copyright notice, this + * list of conditions and the following disclaimer. + * + * Redistributions in binary form must reproduce the above copyright notice, + * this list of conditions and the following disclaimer in the documentation + * and/or other materials provided with the distribution. + * + * Neither the name of ARM nor the names of its contributors may be used + * to endorse or promote products derived from this software without specific + * prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" + * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE + * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR + * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF + * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS + * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN + * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) + * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE + * POSSIBILITY OF SUCH DAMAGE. + */ + +#include <assert.h> +#include <string.h> + +#include <bakery_lock.h> + +#define assert_bakery_entry_valid(entry, bakery) do { \ + assert(bakery); \ + assert(entry < BAKERY_LOCK_MAX_CPUS); \ +} while(0) + +void bakery_lock_init(bakery_lock * bakery) +{ + assert(bakery); + memset(bakery, 0, sizeof(*bakery)); + bakery->owner = NO_OWNER; +} + +void bakery_lock_get(unsigned long mpidr, bakery_lock * bakery) +{ + unsigned int i, max = 0, my_full_number, his_full_number, entry; + + entry = platform_get_core_pos(mpidr); + + assert_bakery_entry_valid(entry, bakery); + + // Catch recursive attempts to take the lock under the same entry: + assert(bakery->owner != entry); + + // Get a ticket + bakery->entering[entry] = 1; + for (i = 0; i < BAKERY_LOCK_MAX_CPUS; ++i) { + if (bakery->number[i] > max) { + max = bakery->number[i]; + } + } + ++max; + bakery->number[entry] = max; + bakery->entering[entry] = 0; + + // Wait for our turn + my_full_number = (max << 8) + entry; + for (i = 0; i < BAKERY_LOCK_MAX_CPUS; ++i) { + while (bakery->entering[i]) ; /* Wait */ + do { + his_full_number = bakery->number[i]; + if (his_full_number) { + his_full_number = (his_full_number << 8) + i; + } + } + while (his_full_number && (his_full_number < my_full_number)); + } + + bakery->owner = entry; +} + +void bakery_lock_release(unsigned long mpidr, bakery_lock * bakery) +{ + unsigned int entry = platform_get_core_pos(mpidr); + + assert_bakery_entry_valid(entry, bakery); + assert(bakery_lock_held(entry, bakery)); + + bakery->owner = NO_OWNER; + bakery->number[entry] = 0; +} + +int bakery_lock_held(unsigned long mpidr, const bakery_lock * bakery) +{ + unsigned int entry = platform_get_core_pos(mpidr); + + assert_bakery_entry_valid(entry, bakery); + + return bakery->owner == entry; +} diff --git a/lib/sync/locks/exclusive/spinlock.S b/lib/sync/locks/exclusive/spinlock.S new file mode 100644 index 0000000..4269d95 --- /dev/null +++ b/lib/sync/locks/exclusive/spinlock.S @@ -0,0 +1,50 @@ +/* + * Copyright (c) 2013, ARM Limited. All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions are met: + * + * Redistributions of source code must retain the above copyright notice, this + * list of conditions and the following disclaimer. + * + * Redistributions in binary form must reproduce the above copyright notice, + * this list of conditions and the following disclaimer in the documentation + * and/or other materials provided with the distribution. + * + * Neither the name of ARM nor the names of its contributors may be used + * to endorse or promote products derived from this software without specific + * prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" + * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE + * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR + * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF + * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS + * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN + * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) + * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE + * POSSIBILITY OF SUCH DAMAGE. + */ + + .globl spin_lock + .globl spin_unlock + + + .section .text, "ax"; + +spin_lock:; .type spin_lock, %function + mov w2, #1 + sevl +l1: wfe +l2: ldaxr w1, [x0] + cbnz w1, l1 + stxr w1, w2, [x0] + cbnz w1, l2 + ret + + +spin_unlock:; .type spin_unlock, %function + stlr wzr, [x0] + ret |