ARM64: kernel: unify ACPI and DT cpus initialization

The code that initializes cpus on arm64 is currently split in two
different code paths that carry out DT and ACPI cpus initialization.

Most of the code executing SMP initialization is common and should
be merged to reduce discrepancies between ACPI and DT initialization
and to have code initializing cpus in a single common place in the
kernel.

This patch refactors arm64 SMP cpus initialization code to merge
ACPI and DT boot paths in a common file and to create sanity
checks that can be reused by both boot methods.

Current code assumes PSCI is the only available boot method
when arm64 boots with ACPI; this can be easily extended if/when
the ACPI parking protocol is merged into the kernel.

Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Acked-by: Hanjun Guo <hanjun.guo@linaro.org>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Tested-by: Hanjun Guo <hanjun.guo@linaro.org>
Tested-by: Mark Rutland <mark.rutland@arm.com> [DT]
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>

1 files changed, 0 insertions, 124 deletions

diff --git a/arch/arm64/kernel/acpi.c b/arch/arm64/kernel/acpi.c
index 945cc1fb3c78..732f57b8731b 100644
--- a/arch/arm64/kernel/acpi.c
+++ b/arch/arm64/kernel/acpi.c
@@ -36,12 +36,6 @@ EXPORT_SYMBOL(acpi_disabled);
 int acpi_pci_disabled = 1;	/* skip ACPI PCI scan and IRQ initialization */
 EXPORT_SYMBOL(acpi_pci_disabled);
 
-/* Processors with enabled flag and sane MPIDR */
-static int enabled_cpus;
-
-/* Boot CPU is valid or not in MADT */
-static bool bootcpu_valid  __initdata;
-
 static bool param_acpi_off __initdata;
 static bool param_acpi_force __initdata;
 
@@ -95,124 +89,6 @@ void __init __acpi_unmap_table(char *map, unsigned long size)
 	early_memunmap(map, size);
 }
 
-/**
- * acpi_map_gic_cpu_interface - generates a logical cpu number
- * and map to MPIDR represented by GICC structure
- */
-static void __init
-acpi_map_gic_cpu_interface(struct acpi_madt_generic_interrupt *processor)
-{
-	int i;
-	u64 mpidr = processor->arm_mpidr & MPIDR_HWID_BITMASK;
-	bool enabled = !!(processor->flags & ACPI_MADT_ENABLED);
-
-	if (mpidr == INVALID_HWID) {
-		pr_info("Skip MADT cpu entry with invalid MPIDR\n");
-		return;
-	}
-
-	total_cpus++;
-	if (!enabled)
-		return;
-
-	if (enabled_cpus >=  NR_CPUS) {
-		pr_warn("NR_CPUS limit of %d reached, Processor %d/0x%llx ignored.\n",
-			NR_CPUS, total_cpus, mpidr);
-		return;
-	}
-
-	/* Check if GICC structure of boot CPU is available in the MADT */
-	if (cpu_logical_map(0) == mpidr) {
-		if (bootcpu_valid) {
-			pr_err("Firmware bug, duplicate CPU MPIDR: 0x%llx in MADT\n",
-			       mpidr);
-			return;
-		}
-
-		bootcpu_valid = true;
-	}
-
-	/*
-	 * Duplicate MPIDRs are a recipe for disaster. Scan
-	 * all initialized entries and check for
-	 * duplicates. If any is found just ignore the CPU.
-	 */
-	for (i = 1; i < enabled_cpus; i++) {
-		if (cpu_logical_map(i) == mpidr) {
-			pr_err("Firmware bug, duplicate CPU MPIDR: 0x%llx in MADT\n",
-			       mpidr);
-			return;
-		}
-	}
-
-	if (!acpi_psci_present())
-		return;
-
-	cpu_ops[enabled_cpus] = cpu_get_ops("psci");
-	/* CPU 0 was already initialized */
-	if (enabled_cpus) {
-		if (!cpu_ops[enabled_cpus])
-			return;
-
-		if (cpu_ops[enabled_cpus]->cpu_init(enabled_cpus))
-			return;
-
-		/* map the logical cpu id to cpu MPIDR */
-		cpu_logical_map(enabled_cpus) = mpidr;
-	}
-
-	enabled_cpus++;
-}
-
-static int __init
-acpi_parse_gic_cpu_interface(struct acpi_subtable_header *header,
-				const unsigned long end)
-{
-	struct acpi_madt_generic_interrupt *processor;
-
-	processor = (struct acpi_madt_generic_interrupt *)header;
-
-	if (BAD_MADT_ENTRY(processor, end))
-		return -EINVAL;
-
-	acpi_table_print_madt_entry(header);
-	acpi_map_gic_cpu_interface(processor);
-	return 0;
-}
-
-/* Parse GIC cpu interface entries in MADT for SMP init */
-void __init acpi_init_cpus(void)
-{
-	int count, i;
-
-	/*
-	 * do a partial walk of MADT to determine how many CPUs
-	 * we have including disabled CPUs, and get information
-	 * we need for SMP init
-	 */
-	count = acpi_table_parse_madt(ACPI_MADT_TYPE_GENERIC_INTERRUPT,
-			acpi_parse_gic_cpu_interface, 0);
-
-	if (!count) {
-		pr_err("No GIC CPU interface entries present\n");
-		return;
-	} else if (count < 0) {
-		pr_err("Error parsing GIC CPU interface entry\n");
-		return;
-	}
-
-	if (!bootcpu_valid) {
-		pr_err("MADT missing boot CPU MPIDR, not enabling secondaries\n");
-		return;
-	}
-
-	for (i = 0; i < enabled_cpus; i++)
-		set_cpu_possible(i, true);
-
-	/* Make boot-up look pretty */
-	pr_info("%d CPUs enabled, %d CPUs total\n", enabled_cpus, total_cpus);
-}
-
 /*
  * acpi_fadt_sanity_check() - Check FADT presence and carry out sanity
  *			      checks on it