linux/arch/arm64/include/asm/hardirq.h
Lorenzo Pieralisi 5e89c55e4e arm64: kernel: implement ACPI parking protocol
The SBBR and ACPI specifications allow ACPI based systems that do not
implement PSCI (eg systems with no EL3) to boot through the ACPI parking
protocol specification[1].

This patch implements the ACPI parking protocol CPU operations, and adds
code that eases parsing the parking protocol data structures to the
ARM64 SMP initializion carried out at the same time as cpus enumeration.

To wake-up the CPUs from the parked state, this patch implements a
wakeup IPI for ARM64 (ie arch_send_wakeup_ipi_mask()) that mirrors the
ARM one, so that a specific IPI is sent for wake-up purpose in order
to distinguish it from other IPI sources.

Given the current ACPI MADT parsing API, the patch implements a glue
layer that helps passing MADT GICC data structure from SMP initialization
code to the parking protocol implementation somewhat overriding the CPU
operations interfaces. This to avoid creating a completely trasparent
DT/ACPI CPU operations layer that would require creating opaque
structure handling for CPUs data (DT represents CPU through DT nodes, ACPI
through static MADT table entries), which seems overkill given that ACPI
on ARM64 mandates only two booting protocols (PSCI and parking protocol),
so there is no need for further protocol additions.

Based on the original work by Mark Salter <msalter@redhat.com>

[1] https://acpica.org/sites/acpica/files/MP%20Startup%20for%20ARM%20platforms.docx

Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Tested-by: Loc Ho <lho@apm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Hanjun Guo <hanjun.guo@linaro.org>
Cc: Sudeep Holla <sudeep.holla@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mark Salter <msalter@redhat.com>
Cc: Al Stone <ahs3@redhat.com>
[catalin.marinas@arm.com: Added WARN_ONCE(!acpi_parking_protocol_valid() on the IPI]
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2016-02-16 15:12:32 +00:00

47 lines
1.3 KiB
C

/*
* 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_HARDIRQ_H
#define __ASM_HARDIRQ_H
#include <linux/cache.h>
#include <linux/threads.h>
#include <asm/irq.h>
#define NR_IPI 6
typedef struct {
unsigned int __softirq_pending;
unsigned int ipi_irqs[NR_IPI];
} ____cacheline_aligned irq_cpustat_t;
#include <linux/irq_cpustat.h> /* Standard mappings for irq_cpustat_t above */
#define __inc_irq_stat(cpu, member) __IRQ_STAT(cpu, member)++
#define __get_irq_stat(cpu, member) __IRQ_STAT(cpu, member)
u64 smp_irq_stat_cpu(unsigned int cpu);
#define arch_irq_stat_cpu smp_irq_stat_cpu
#define __ARCH_IRQ_EXIT_IRQS_DISABLED 1
static inline void ack_bad_irq(unsigned int irq)
{
extern unsigned long irq_err_count;
irq_err_count++;
}
#endif /* __ASM_HARDIRQ_H */