Merge tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux

Pull initial ACPI support for arm64 from Will Deacon:
 "This series introduces preliminary ACPI 5.1 support to the arm64
  kernel using the "hardware reduced" profile.  We don't support any
  peripherals yet, so it's fairly limited in scope:

   - MEMORY init (UEFI)

   - ACPI discovery (RSDP via UEFI)

   - CPU init (FADT)

   - GIC init (MADT)

   - SMP boot (MADT + PSCI)

   - ACPI Kconfig options (dependent on EXPERT)

  ACPI for arm64 has been in development for a while now and hardware
  has been available that can boot with either FDT or ACPI tables.  This
  has been made possible by both changes to the ACPI spec to cater for
  ARM-based machines (known as "hardware-reduced" in ACPI parlance) but
  also a Linaro-driven effort to get this supported on top of the Linux
  kernel.  This pull request is the result of that work.

  These changes allow us to initialise the CPUs, interrupt controller,
  and timers via ACPI tables, with memory information and cmdline coming
  from EFI.  We don't support a hybrid ACPI/FDT scheme.  Of course,
  there is still plenty of work to do (a serial console would be nice!)
  but I expect that to happen on a per-driver basis after this core
  series has been merged.

  Anyway, the diff stat here is fairly horrible, but splitting this up
  and merging it via all the different subsystems would have been
  extremely painful.  Instead, we've got all the relevant Acks in place
  and I've not seen anything other than trivial (Kconfig) conflicts in
  -next (for completeness, I've included my resolution below).  Nearly
  half of the insertions fall under Documentation/.

  So, we'll see how this goes.  Right now, it all depends on EXPERT and
  I fully expect people to use FDT by default for the immediate future"

* tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (31 commits)
  ARM64 / ACPI: make acpi_map_gic_cpu_interface() as void function
  ARM64 / ACPI: Ignore the return error value of acpi_map_gic_cpu_interface()
  ARM64 / ACPI: fix usage of acpi_map_gic_cpu_interface
  ARM64: kernel: acpi: honour acpi=force command line parameter
  ARM64: kernel: acpi: refactor ACPI tables init and checks
  ARM64: kernel: psci: let ACPI probe PSCI version
  ARM64: kernel: psci: factor out probe function
  ACPI: move arm64 GSI IRQ model to generic GSI IRQ layer
  ARM64 / ACPI: Don't unflatten device tree if acpi=force is passed
  ARM64 / ACPI: additions of ACPI documentation for arm64
  Documentation: ACPI for ARM64
  ARM64 / ACPI: Enable ARM64 in Kconfig
  XEN / ACPI: Make XEN ACPI depend on X86
  ARM64 / ACPI: Select ACPI_REDUCED_HARDWARE_ONLY if ACPI is enabled on ARM64
  clocksource / arch_timer: Parse GTDT to initialize arch timer
  irqchip: Add GICv2 specific ACPI boot support
  ARM64 / ACPI: Introduce ACPI_IRQ_MODEL_GIC and register device's gsi
  ACPI / processor: Make it possible to get CPU hardware ID via GICC
  ACPI / processor: Introduce phys_cpuid_t for CPU hardware ID
  ARM64 / ACPI: Parse MADT for SMP initialization
  ...

2 files changed, 107 insertions, 0 deletions

diff --git a/drivers/irqchip/irq-gic.c b/drivers/irqchip/irq-gic.c
index a6ce3476834e..7b315e385ba3 100644
--- a/drivers/irqchip/irq-gic.c
+++ b/drivers/irqchip/irq-gic.c
@@ -33,12 +33,14 @@
 #include <linux/of.h>
 #include <linux/of_address.h>
 #include <linux/of_irq.h>
+#include <linux/acpi.h>
 #include <linux/irqdomain.h>
 #include <linux/interrupt.h>
 #include <linux/percpu.h>
 #include <linux/slab.h>
 #include <linux/irqchip/chained_irq.h>
 #include <linux/irqchip/arm-gic.h>
+#include <linux/irqchip/arm-gic-acpi.h>
 
 #include <asm/cputype.h>
 #include <asm/irq.h>
@@ -1107,3 +1109,105 @@ IRQCHIP_DECLARE(msm_8660_qgic, "qcom,msm-8660-qgic", gic_of_init);
 IRQCHIP_DECLARE(msm_qgic2, "qcom,msm-qgic2", gic_of_init);
 
 #endif
+
+#ifdef CONFIG_ACPI
+static phys_addr_t dist_phy_base, cpu_phy_base __initdata;
+
+static int __init
+gic_acpi_parse_madt_cpu(struct acpi_subtable_header *header,
+                        const unsigned long end)
+{
+        struct acpi_madt_generic_interrupt *processor;
+        phys_addr_t gic_cpu_base;
+        static int cpu_base_assigned;
+
+        processor = (struct acpi_madt_generic_interrupt *)header;
+
+        if (BAD_MADT_ENTRY(processor, end))
+                return -EINVAL;
+
+        /*
+         * There is no support for non-banked GICv1/2 register in ACPI spec.
+         * All CPU interface addresses have to be the same.
+         */
+        gic_cpu_base = processor->base_address;
+        if (cpu_base_assigned && gic_cpu_base != cpu_phy_base)
+                return -EINVAL;
+
+        cpu_phy_base = gic_cpu_base;
+        cpu_base_assigned = 1;
+        return 0;
+}
+
+static int __init
+gic_acpi_parse_madt_distributor(struct acpi_subtable_header *header,
+                                const unsigned long end)
+{
+        struct acpi_madt_generic_distributor *dist;
+
+        dist = (struct acpi_madt_generic_distributor *)header;
+
+        if (BAD_MADT_ENTRY(dist, end))
+                return -EINVAL;
+
+        dist_phy_base = dist->base_address;
+        return 0;
+}
+
+int __init
+gic_v2_acpi_init(struct acpi_table_header *table)
+{
+        void __iomem *cpu_base, *dist_base;
+        int count;
+
+        /* Collect CPU base addresses */
+        count = acpi_parse_entries(ACPI_SIG_MADT,
+                                   sizeof(struct acpi_table_madt),
+                                   gic_acpi_parse_madt_cpu, table,
+                                   ACPI_MADT_TYPE_GENERIC_INTERRUPT, 0);
+        if (count <= 0) {
+                pr_err("No valid GICC entries exist\n");
+                return -EINVAL;
+        }
+
+        /*
+         * Find distributor base address. We expect one distributor entry since
+         * ACPI 5.1 spec neither support multi-GIC instances nor GIC cascade.
+         */
+        count = acpi_parse_entries(ACPI_SIG_MADT,
+                                   sizeof(struct acpi_table_madt),
+                                   gic_acpi_parse_madt_distributor, table,
+                                   ACPI_MADT_TYPE_GENERIC_DISTRIBUTOR, 0);
+        if (count <= 0) {
+                pr_err("No valid GICD entries exist\n");
+                return -EINVAL;
+        } else if (count > 1) {
+                pr_err("More than one GICD entry detected\n");
+                return -EINVAL;
+        }
+
+        cpu_base = ioremap(cpu_phy_base, ACPI_GIC_CPU_IF_MEM_SIZE);
+        if (!cpu_base) {
+                pr_err("Unable to map GICC registers\n");
+                return -ENOMEM;
+        }
+
+        dist_base = ioremap(dist_phy_base, ACPI_GICV2_DIST_MEM_SIZE);
+        if (!dist_base) {
+                pr_err("Unable to map GICD registers\n");
+                iounmap(cpu_base);
+                return -ENOMEM;
+        }
+
+        /*
+         * Initialize zero GIC instance (no multi-GIC support). Also, set GIC
+         * as default IRQ domain to allow for GSI registration and GSI to IRQ
+         * number translation (see acpi_register_gsi() and acpi_gsi_to_irq()).
+         */
+        gic_init_bases(0, -1, dist_base, cpu_base, 0, NULL);
+        irq_set_default_host(gic_data[0].domain);
+
+        acpi_irq_model = ACPI_IRQ_MODEL_GIC;
+        return 0;
+}
+#endif
diff --git a/drivers/irqchip/irqchip.c b/drivers/irqchip/irqchip.c
index 0fe2f718d81c..afd1af3dfe5a 100644
--- a/drivers/irqchip/irqchip.c
+++ b/drivers/irqchip/irqchip.c
@@ -8,6 +8,7 @@
  * warranty of any kind, whether express or implied.
  */
 
+#include <linux/acpi_irq.h>
 #include <linux/init.h>
 #include <linux/of_irq.h>
 #include <linux/irqchip.h>
@@ -26,4 +27,6 @@ extern struct of_device_id __irqchip_of_table[];
 void __init irqchip_init(void)
 {
         of_irq_init(__irqchip_of_table);
+
+        acpi_irq_init();
 }