arm-trusted-firmware/bl31/bl31_context_mgmt.c

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/*
PSCI: Introduce new platform and CM helper APIs This patch introduces new platform APIs and context management helper APIs to support the new topology framework based on linear core position. This framework will be introduced in the follwoing patch and it removes the assumption that the MPIDR based affinity levels map directly to levels in a power domain tree. The new platforms APIs and context management helpers based on core position are as described below: * plat_my_core_pos() and plat_core_pos_by_mpidr() These 2 new mandatory platform APIs are meant to replace the existing 'platform_get_core_pos()' API. The 'plat_my_core_pos()' API returns the linear index of the calling core and 'plat_core_pos_by_mpidr()' returns the linear index of a core specified by its MPIDR. The latter API will also validate the MPIDR passed as an argument and will return an error code (-1) if an invalid MPIDR is passed as the argument. This enables the caller to safely convert an MPIDR of another core to its linear index without querying the PSCI topology tree e.g. during a call to PSCI CPU_ON. Since the 'plat_core_pos_by_mpidr()' API verifies an MPIDR, which is always platform specific, it is no longer possible to maintain a default implementation of this API. Also it might not be possible for a platform port to verify an MPIDR before the C runtime has been setup or the topology has been initialized. This would prevent 'plat_core_pos_by_mpidr()' from being callable prior to topology setup. As a result, the generic Trusted Firmware code does not call this API before the topology setup has been done. The 'plat_my_core_pos' API should be able to run without a C runtime. Since this API needs to return a core position which is equal to the one returned by 'plat_core_pos_by_mpidr()' API for the corresponding MPIDR, this too cannot have default implementation and is a mandatory API for platform ports. These APIs will be implemented by the ARM reference platform ports later in the patch stack. * plat_get_my_stack() and plat_set_my_stack() These APIs are the stack management APIs which set/return stack addresses appropriate for the calling core. These replace the 'platform_get_stack()' and 'platform_set_stack()' APIs. A default weak MP version and a global UP version of these APIs are provided for the platforms. * Context management helpers based on linear core position A set of new context management(CM) helpers viz cm_get_context_by_index(), cm_set_context_by_index(), cm_init_my_context() and cm_init_context_by_index() are defined which are meant to replace the old helpers which took MPIDR as argument. The old CM helpers are implemented based on the new helpers to allow for code consolidation and will be deprecated once the switch to the new framework is done. Change-Id: I89758632b370c2812973a4b2efdd9b81a41f9b69
2015-04-09 13:40:55 +01:00
* Copyright (c) 2013-2015, ARM Limited and Contributors. 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 <bl31.h>
#include <context.h>
#include <context_mgmt.h>
#include <cpu_data.h>
#include <platform.h>
/*******************************************************************************
* This function returns a pointer to the most recent 'cpu_context' structure
* for the calling CPU that was set as the context for the specified security
* state. NULL is returned if no such structure has been specified.
******************************************************************************/
void *cm_get_context(uint32_t security_state)
{
assert(security_state <= NON_SECURE);
return get_cpu_data(cpu_context[security_state]);
}
/*******************************************************************************
* This function sets the pointer to the current 'cpu_context' structure for the
* specified security state for the calling CPU
******************************************************************************/
void cm_set_context(void *context, uint32_t security_state)
{
assert(security_state <= NON_SECURE);
set_cpu_data(cpu_context[security_state], context);
}
/*******************************************************************************
* This function returns a pointer to the most recent 'cpu_context' structure
* for the CPU identified by `cpu_idx` that was set as the context for the
* specified security state. NULL is returned if no such structure has been
* specified.
******************************************************************************/
void *cm_get_context_by_index(unsigned int cpu_idx,
unsigned int security_state)
{
assert(sec_state_is_valid(security_state));
return get_cpu_data_by_index(cpu_idx, cpu_context[security_state]);
}
/*******************************************************************************
* This function sets the pointer to the current 'cpu_context' structure for the
* specified security state for the CPU identified by CPU index.
******************************************************************************/
void cm_set_context_by_index(unsigned int cpu_idx, void *context,
unsigned int security_state)
{
assert(sec_state_is_valid(security_state));
set_cpu_data_by_index(cpu_idx, cpu_context[security_state], context);
}
#if !ERROR_DEPRECATED
/*
* These context management helpers are deprecated but are maintained for use
* by SPDs which have not migrated to the new API. If ERROR_DEPRECATED
* is enabled, these are excluded from the build so as to force users to
* migrate to the new API.
*/
/*******************************************************************************
* This function returns a pointer to the most recent 'cpu_context' structure
* for the CPU identified by MPIDR that was set as the context for the specified
* security state. NULL is returned if no such structure has been specified.
******************************************************************************/
void *cm_get_context_by_mpidr(uint64_t mpidr, uint32_t security_state)
{
assert(sec_state_is_valid(security_state));
return cm_get_context_by_index(platform_get_core_pos(mpidr), security_state);
}
/*******************************************************************************
* This function sets the pointer to the current 'cpu_context' structure for the
* specified security state for the CPU identified by MPIDR
******************************************************************************/
void cm_set_context_by_mpidr(uint64_t mpidr, void *context, uint32_t security_state)
{
assert(sec_state_is_valid(security_state));
cm_set_context_by_index(platform_get_core_pos(mpidr),
context, security_state);
}
/*******************************************************************************
* The following function provides a compatibility function for SPDs using the
* existing cm library routines. This function is expected to be invoked for
* initializing the cpu_context for the CPU specified by MPIDR for first use.
******************************************************************************/
void cm_init_context(unsigned long mpidr, const entry_point_info_t *ep)
{
if ((mpidr & MPIDR_AFFINITY_MASK) ==
(read_mpidr_el1() & MPIDR_AFFINITY_MASK))
cm_init_my_context(ep);
else
cm_init_context_by_index(platform_get_core_pos(mpidr), ep);
}
#endif