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OpenCloudOS-Kernel/arch/openrisc/include/asm/time.h

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openrisc: initial SMP support This patch introduces the SMP support for the OpenRISC architecture. The SMP architecture requires cores which have multi-core features which have been introduced a few years back including: - New SPRS SPR_COREID SPR_NUMCORES - Shadow SPRs - Atomic Instructions - Cache Coherency - A wired in IPI controller This patch adds all of the SMP specific changes to core infrastructure, it looks big but it needs to go all together as its hard to split this one up. Boot loader spinning of second cpu is not supported yet, it's assumed that Linux is booted straight after cpu reset. The bulk of these changes are trivial changes to refactor to use per cpu data structures throughout. The addition of the smp.c and changes in time.c are the changes. Some specific notes: MM changes ---------- The reason why this is created as an array, and not with DEFINE_PER_CPU is that doing it this way, we'll save a load in the tlb-miss handler (the load from __per_cpu_offset). TLB Flush --------- The SMP implementation of flush_tlb_* works by sending out a function-call IPI to all the non-local cpus by using the generic on_each_cpu() function. Currently, all flush_tlb_* functions will result in a flush_tlb_all(), which has always been the behaviour in the UP case. CPU INFO -------- This creates a per cpu cpuinfo struct and fills it out accordingly for each activated cpu. show_cpuinfo is also updated to reflect new version information in later versions of the spec. SMP API ------- This imitates the arm64 implementation by having a smp_cross_call callback that can be set by set_smp_cross_call to initiate an IPI and a handle_IPI function that is expected to be called from an IPI irqchip driver. Signed-off-by: Stefan Kristiansson <stefan.kristiansson@saunalahti.fi> [shorne@gmail.com: added cpu stop, checkpatch fixes, wrote commit message] Signed-off-by: Stafford Horne <shorne@gmail.com>
2014-05-12 02:49:34 +08:00
/*
* OpenRISC timer API
*
* Copyright (C) 2017 by Stafford Horne (shorne@gmail.com)
*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*/
#ifndef __ASM_OR1K_TIME_H
#define __ASM_OR1K_TIME_H
extern void openrisc_clockevent_init(void);
openrisc: add tick timer multi-core sync logic In case timers are not in sync when cpus start (i.e. hot plug / offset resets) we need to synchronize the secondary cpus internal timer with the main cpu. This is needed as in OpenRISC SMP there is only one clocksource registered which reads from the same ttcr register on each cpu. This synchronization routine heavily borrows from mips implementation that does something similar. Signed-off-by: Stafford Horne <shorne@gmail.com>
2017-07-07 05:06:30 +08:00
extern void openrisc_timer_set(unsigned long count);
extern void openrisc_timer_set_next(unsigned long delta);
#ifdef CONFIG_SMP
extern void synchronise_count_master(int cpu);
extern void synchronise_count_slave(int cpu);
#endif
openrisc: initial SMP support This patch introduces the SMP support for the OpenRISC architecture. The SMP architecture requires cores which have multi-core features which have been introduced a few years back including: - New SPRS SPR_COREID SPR_NUMCORES - Shadow SPRs - Atomic Instructions - Cache Coherency - A wired in IPI controller This patch adds all of the SMP specific changes to core infrastructure, it looks big but it needs to go all together as its hard to split this one up. Boot loader spinning of second cpu is not supported yet, it's assumed that Linux is booted straight after cpu reset. The bulk of these changes are trivial changes to refactor to use per cpu data structures throughout. The addition of the smp.c and changes in time.c are the changes. Some specific notes: MM changes ---------- The reason why this is created as an array, and not with DEFINE_PER_CPU is that doing it this way, we'll save a load in the tlb-miss handler (the load from __per_cpu_offset). TLB Flush --------- The SMP implementation of flush_tlb_* works by sending out a function-call IPI to all the non-local cpus by using the generic on_each_cpu() function. Currently, all flush_tlb_* functions will result in a flush_tlb_all(), which has always been the behaviour in the UP case. CPU INFO -------- This creates a per cpu cpuinfo struct and fills it out accordingly for each activated cpu. show_cpuinfo is also updated to reflect new version information in later versions of the spec. SMP API ------- This imitates the arm64 implementation by having a smp_cross_call callback that can be set by set_smp_cross_call to initiate an IPI and a handle_IPI function that is expected to be called from an IPI irqchip driver. Signed-off-by: Stefan Kristiansson <stefan.kristiansson@saunalahti.fi> [shorne@gmail.com: added cpu stop, checkpatch fixes, wrote commit message] Signed-off-by: Stafford Horne <shorne@gmail.com>
2014-05-12 02:49:34 +08:00
#endif /* __ASM_OR1K_TIME_H */