Lines Matching refs:in
12 algorithm in use.
28 means that we need some coordination in order to ensure that critical
37 methods of coordination are required in order to guarantee safe
40 The mechanism presented in this document describes a coherent memory
77 level. A CPU in this state is not necessarily being used
86 Each CPU has one of these states assigned to it at any point in time.
87 The CPU states are described in the "CPU state" section, below.
91 to introduce additional states in order to avoid races between different
92 CPUs in the cluster simultaneously modifying the state. The cluster-
93 level states are described in the "Cluster state" section.
95 To help distinguish the CPU states from cluster states in this
103 In this algorithm, each individual core in a multi-core processor is
105 therefore, a CPU can only be doing one thing at a single point in time.
109 The algorithm defines the following states for each CPU in the system:
160 A CPU cannot start participating in hardware coherency until the
162 then the CPU will wait in the CPU_COMING_UP state until the
168 The CPU's parent cluster must be in CLUSTER_UP.
178 start participating in local coherency.
189 The CPU remains in this state until an explicit policy decision
201 While in this state, the CPU exits coherency, including any
225 In order to enable safe coordination in such situations, it is important
243 The different pairings of these states results in six possible
273 be decided in advance by some other means. Refer to the section
282 INBOUND_NOT_COMING_UP (corresponding to GOING_DOWN in the basic
284 COMING_UP in the basic model). The second path avoids cluster
287 CLUSTER_UP/INBOUND_COMING_UP is equivalent to UP in the basic
294 The next state in each case is notated
320 in order to achieve this.
323 setup to enable other CPUs in the cluster to enter coherency
337 enabled for the cluster. Other CPUs in the cluster can safely
355 enabled for the cluster. Other CPUs in the cluster can safely
358 The cluster will remain in this state until a policy decision is
372 must wait in this state until all CPUs in the cluster are in the
375 When all CPUs are in the CPU_DOWN state, the cluster can be torn
408 come online in the meantime and is trying to set up the cluster
417 in the CLUSTER_DOWN state; the inbound CPU will
421 unnecessary teardown and setup operations in situations where
466 Because CPUs may power up asynchronously in response to external wake-up
473 coherency controls in the bus fabric.
475 The current implementation in mcpm_head.S uses a separate mutual exclusion
476 mechanism to do this arbitration. This mechanism is documented in
477 detail in vlocks.txt.
496 low-level power-up code in mcpm_head.S. This could
497 involve CPU-specific setup code, but in the current
502 and from there to CLUSTER_DOWN or back to CLUSTER_UP (in
510 the low-level power-up code in mcpm_head.S. This
528 Originally created and documented by Dave Martin for Linaro Limited, in
533 License, as defined in linux/COPYING.