linux_dsm_epyc7002/arch/arm64/include/asm/proc-fns.h
Lorenzo Pieralisi 6732bc65c2 arm64: kernel: suspend/resume registers save/restore
Power management software requires the kernel to save and restore
CPU registers while going through suspend and resume operations
triggered by kernel subsystems like CPU idle and suspend to RAM.

This patch implements code that provides save and restore mechanism
for the arm v8 implementation. Memory for the context is passed as
parameter to both cpu_do_suspend and cpu_do_resume functions, and allows
the callers to implement context allocation as they deem fit.

The registers that are saved and restored correspond to the registers set
actually required by the kernel to be up and running which represents a
subset of v8 ISA.

Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
2013-12-16 17:17:31 +00:00

54 lines
1.6 KiB
C

/*
* Based on arch/arm/include/asm/proc-fns.h
*
* Copyright (C) 1997-1999 Russell King
* Copyright (C) 2000 Deep Blue Solutions Ltd
* Copyright (C) 2012 ARM Ltd.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#ifndef __ASM_PROCFNS_H
#define __ASM_PROCFNS_H
#ifdef __KERNEL__
#ifndef __ASSEMBLY__
#include <asm/page.h>
struct mm_struct;
struct cpu_suspend_ctx;
extern void cpu_cache_off(void);
extern void cpu_do_idle(void);
extern void cpu_do_switch_mm(unsigned long pgd_phys, struct mm_struct *mm);
extern void cpu_reset(unsigned long addr) __attribute__((noreturn));
extern void cpu_do_suspend(struct cpu_suspend_ctx *ptr);
extern u64 cpu_do_resume(phys_addr_t ptr, u64 idmap_ttbr);
#include <asm/memory.h>
#define cpu_switch_mm(pgd,mm) cpu_do_switch_mm(virt_to_phys(pgd),mm)
#define cpu_get_pgd() \
({ \
unsigned long pg; \
asm("mrs %0, ttbr0_el1\n" \
: "=r" (pg)); \
pg &= ~0xffff000000003ffful; \
(pgd_t *)phys_to_virt(pg); \
})
#endif /* __ASSEMBLY__ */
#endif /* __KERNEL__ */
#endif /* __ASM_PROCFNS_H */