linux/arch/arm64/kernel/acpi_parking_protocol.c

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// SPDX-License-Identifier: GPL-2.0-only
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>
2016-01-26 19:10:38 +08:00
/*
* ARM64 ACPI Parking Protocol implementation
*
* Authors: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
* Mark Salter <msalter@redhat.com>
*/
#include <linux/acpi.h>
#include <linux/mm.h>
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>
2016-01-26 19:10:38 +08:00
#include <linux/types.h>
#include <asm/cpu_ops.h>
arm64: kernel: acpi: fix ioremap in ACPI parking protocol cpu_postboot When secondary cpus are booted through the ACPI parking protocol, the booted cpu should check that FW has correctly cleared its mailbox entry point value to make sure the boot process was correctly executed. The entry point check is carried in the cpu_ops->cpu_postboot method, that is executed by secondary cpus when entering the kernel with irqs disabled. The ACPI parking protocol cpu_ops maps/unmaps the mailboxes on the primary CPU to trigger secondary boot in the cpu_ops->cpu_boot method and on secondary processors to carry out FW checks on the booted CPU to verify the boot protocol was successfully executed in the cpu_ops->cpu_postboot method. Therefore, the cpu_ops->cpu_postboot method is forced to ioremap/unmap the mailboxes, which is wrong in that ioremap cannot be safely be carried out with irqs disabled. To fix this issue, this patch reshuffles the code so that the mailboxes are still mapped after the boot processor executes the cpu_ops->cpu_boot method for a given cpu, and the VA at which a mailbox is mapped for a given cpu is stashed in the per-cpu data struct so that secondary cpus can retrieve them in the cpu_ops->cpu_postboot and complete the required FW checks. Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> Reported-by: Itaru Kitayama <itaru.kitayama@riken.jp> Tested-by: Loc Ho <lho@apm.com> Tested-by: Itaru Kitayama <itaru.kitayama@riken.jp> Cc: Will Deacon <will.deacon@arm.com> Cc: Hanjun Guo <hanjun.guo@linaro.org> Cc: Loc Ho <lho@apm.com> Cc: Itaru Kitayama <itaru.kitayama@riken.jp> 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> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2016-02-26 19:50:12 +08:00
struct parking_protocol_mailbox {
__le32 cpu_id;
__le32 reserved;
__le64 entry_point;
};
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>
2016-01-26 19:10:38 +08:00
struct cpu_mailbox_entry {
arm64: kernel: acpi: fix ioremap in ACPI parking protocol cpu_postboot When secondary cpus are booted through the ACPI parking protocol, the booted cpu should check that FW has correctly cleared its mailbox entry point value to make sure the boot process was correctly executed. The entry point check is carried in the cpu_ops->cpu_postboot method, that is executed by secondary cpus when entering the kernel with irqs disabled. The ACPI parking protocol cpu_ops maps/unmaps the mailboxes on the primary CPU to trigger secondary boot in the cpu_ops->cpu_boot method and on secondary processors to carry out FW checks on the booted CPU to verify the boot protocol was successfully executed in the cpu_ops->cpu_postboot method. Therefore, the cpu_ops->cpu_postboot method is forced to ioremap/unmap the mailboxes, which is wrong in that ioremap cannot be safely be carried out with irqs disabled. To fix this issue, this patch reshuffles the code so that the mailboxes are still mapped after the boot processor executes the cpu_ops->cpu_boot method for a given cpu, and the VA at which a mailbox is mapped for a given cpu is stashed in the per-cpu data struct so that secondary cpus can retrieve them in the cpu_ops->cpu_postboot and complete the required FW checks. Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> Reported-by: Itaru Kitayama <itaru.kitayama@riken.jp> Tested-by: Loc Ho <lho@apm.com> Tested-by: Itaru Kitayama <itaru.kitayama@riken.jp> Cc: Will Deacon <will.deacon@arm.com> Cc: Hanjun Guo <hanjun.guo@linaro.org> Cc: Loc Ho <lho@apm.com> Cc: Itaru Kitayama <itaru.kitayama@riken.jp> 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> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2016-02-26 19:50:12 +08:00
struct parking_protocol_mailbox __iomem *mailbox;
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>
2016-01-26 19:10:38 +08:00
phys_addr_t mailbox_addr;
u8 version;
u8 gic_cpu_id;
};
static struct cpu_mailbox_entry cpu_mailbox_entries[NR_CPUS];
void __init acpi_set_mailbox_entry(int cpu,
struct acpi_madt_generic_interrupt *p)
{
struct cpu_mailbox_entry *cpu_entry = &cpu_mailbox_entries[cpu];
cpu_entry->mailbox_addr = p->parked_address;
cpu_entry->version = p->parking_version;
cpu_entry->gic_cpu_id = p->cpu_interface_number;
}
bool acpi_parking_protocol_valid(int cpu)
{
struct cpu_mailbox_entry *cpu_entry = &cpu_mailbox_entries[cpu];
return cpu_entry->mailbox_addr && cpu_entry->version;
}
static int acpi_parking_protocol_cpu_init(unsigned int cpu)
{
pr_debug("%s: ACPI parked addr=%llx\n", __func__,
cpu_mailbox_entries[cpu].mailbox_addr);
return 0;
}
static int acpi_parking_protocol_cpu_prepare(unsigned int cpu)
{
return 0;
}
static int acpi_parking_protocol_cpu_boot(unsigned int cpu)
{
struct cpu_mailbox_entry *cpu_entry = &cpu_mailbox_entries[cpu];
struct parking_protocol_mailbox __iomem *mailbox;
u32 cpu_id;
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>
2016-01-26 19:10:38 +08:00
/*
* Map mailbox memory with attribute device nGnRE (ie ioremap -
* this deviates from the parking protocol specifications since
* the mailboxes are required to be mapped nGnRnE; the attribute
* discrepancy is harmless insofar as the protocol specification
* is concerned).
* If the mailbox is mistakenly allocated in the linear mapping
* by FW ioremap will fail since the mapping will be prevented
* by the kernel (it clashes with the linear mapping attributes
* specifications).
*/
mailbox = ioremap(cpu_entry->mailbox_addr, sizeof(*mailbox));
if (!mailbox)
return -EIO;
cpu_id = readl_relaxed(&mailbox->cpu_id);
/*
* Check if firmware has set-up the mailbox entry properly
* before kickstarting the respective cpu.
*/
if (cpu_id != ~0U) {
iounmap(mailbox);
return -ENXIO;
}
arm64: kernel: acpi: fix ioremap in ACPI parking protocol cpu_postboot When secondary cpus are booted through the ACPI parking protocol, the booted cpu should check that FW has correctly cleared its mailbox entry point value to make sure the boot process was correctly executed. The entry point check is carried in the cpu_ops->cpu_postboot method, that is executed by secondary cpus when entering the kernel with irqs disabled. The ACPI parking protocol cpu_ops maps/unmaps the mailboxes on the primary CPU to trigger secondary boot in the cpu_ops->cpu_boot method and on secondary processors to carry out FW checks on the booted CPU to verify the boot protocol was successfully executed in the cpu_ops->cpu_postboot method. Therefore, the cpu_ops->cpu_postboot method is forced to ioremap/unmap the mailboxes, which is wrong in that ioremap cannot be safely be carried out with irqs disabled. To fix this issue, this patch reshuffles the code so that the mailboxes are still mapped after the boot processor executes the cpu_ops->cpu_boot method for a given cpu, and the VA at which a mailbox is mapped for a given cpu is stashed in the per-cpu data struct so that secondary cpus can retrieve them in the cpu_ops->cpu_postboot and complete the required FW checks. Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> Reported-by: Itaru Kitayama <itaru.kitayama@riken.jp> Tested-by: Loc Ho <lho@apm.com> Tested-by: Itaru Kitayama <itaru.kitayama@riken.jp> Cc: Will Deacon <will.deacon@arm.com> Cc: Hanjun Guo <hanjun.guo@linaro.org> Cc: Loc Ho <lho@apm.com> Cc: Itaru Kitayama <itaru.kitayama@riken.jp> 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> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2016-02-26 19:50:12 +08:00
/*
* stash the mailbox address mapping to use it for further FW
* checks in the postboot method
*/
cpu_entry->mailbox = mailbox;
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>
2016-01-26 19:10:38 +08:00
/*
* We write the entry point and cpu id as LE regardless of the
* native endianness of the kernel. Therefore, any boot-loaders
* that read this address need to convert this address to the
* Boot-Loader's endianness before jumping.
*/
writeq_relaxed(__pa_symbol(function_nocfi(secondary_entry)),
&mailbox->entry_point);
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>
2016-01-26 19:10:38 +08:00
writel_relaxed(cpu_entry->gic_cpu_id, &mailbox->cpu_id);
arch_send_wakeup_ipi_mask(cpumask_of(cpu));
return 0;
}
static void acpi_parking_protocol_cpu_postboot(void)
{
int cpu = smp_processor_id();
struct cpu_mailbox_entry *cpu_entry = &cpu_mailbox_entries[cpu];
arm64: kernel: acpi: fix ioremap in ACPI parking protocol cpu_postboot When secondary cpus are booted through the ACPI parking protocol, the booted cpu should check that FW has correctly cleared its mailbox entry point value to make sure the boot process was correctly executed. The entry point check is carried in the cpu_ops->cpu_postboot method, that is executed by secondary cpus when entering the kernel with irqs disabled. The ACPI parking protocol cpu_ops maps/unmaps the mailboxes on the primary CPU to trigger secondary boot in the cpu_ops->cpu_boot method and on secondary processors to carry out FW checks on the booted CPU to verify the boot protocol was successfully executed in the cpu_ops->cpu_postboot method. Therefore, the cpu_ops->cpu_postboot method is forced to ioremap/unmap the mailboxes, which is wrong in that ioremap cannot be safely be carried out with irqs disabled. To fix this issue, this patch reshuffles the code so that the mailboxes are still mapped after the boot processor executes the cpu_ops->cpu_boot method for a given cpu, and the VA at which a mailbox is mapped for a given cpu is stashed in the per-cpu data struct so that secondary cpus can retrieve them in the cpu_ops->cpu_postboot and complete the required FW checks. Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> Reported-by: Itaru Kitayama <itaru.kitayama@riken.jp> Tested-by: Loc Ho <lho@apm.com> Tested-by: Itaru Kitayama <itaru.kitayama@riken.jp> Cc: Will Deacon <will.deacon@arm.com> Cc: Hanjun Guo <hanjun.guo@linaro.org> Cc: Loc Ho <lho@apm.com> Cc: Itaru Kitayama <itaru.kitayama@riken.jp> 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> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2016-02-26 19:50:12 +08:00
struct parking_protocol_mailbox __iomem *mailbox = cpu_entry->mailbox;
u64 entry_point;
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>
2016-01-26 19:10:38 +08:00
entry_point = readq_relaxed(&mailbox->entry_point);
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>
2016-01-26 19:10:38 +08:00
/*
* Check if firmware has cleared the entry_point as expected
* by the protocol specification.
*/
WARN_ON(entry_point);
}
const struct cpu_operations acpi_parking_protocol_ops = {
.name = "parking-protocol",
.cpu_init = acpi_parking_protocol_cpu_init,
.cpu_prepare = acpi_parking_protocol_cpu_prepare,
.cpu_boot = acpi_parking_protocol_cpu_boot,
.cpu_postboot = acpi_parking_protocol_cpu_postboot
};