ARM64 / ACPI: Introduce ACPI_IRQ_MODEL_GIC and register device's gsi

Introduce ACPI_IRQ_MODEL_GIC which is needed for ARM64 as GIC is
used, and then register device's gsi with the core IRQ subsystem.

acpi_register_gsi() is similar to DT based irq_of_parse_and_map(),
since gsi is unique in the system, so use hwirq number directly
for the mapping.

We are going to implement stacked domains when GICv2m, GICv3, ITS
support are added.

CC: Marc Zyngier <marc.zyngier@arm.com>
Originally-by: Amit Daniel Kachhap <amit.daniel@samsung.com>
Tested-by: Suravee Suthikulpanit <Suravee.Suthikulpanit@amd.com>
Tested-by: Yijing Wang <wangyijing@huawei.com>
Tested-by: Mark Langsdorf <mlangsdo@redhat.com>
Tested-by: Jon Masters <jcm@redhat.com>
Tested-by: Timur Tabi <timur@codeaurora.org>
Tested-by: Robert Richter <rrichter@cavium.com>
Acked-by: Robert Richter <rrichter@cavium.com>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Grant Likely <grant.likely@linaro.org>
Signed-off-by: Hanjun Guo <hanjun.guo@linaro.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>

diff --git a/arch/arm64/kernel/acpi.c b/arch/arm64/kernel/acpi.c
index c9203c0..dec6f8a 100644 (file)
--- a/arch/arm64/kernel/acpi.c
+++ b/arch/arm64/kernel/acpi.c
@@ -75,6 +75,12 @@ static int __init dt_scan_depth1_nodes(unsigned long node,
        return 0;
 }
 
+/*
+ * Since we're on ARM, the default interrupt routing model
+ * clearly has to be GIC.
+ */
+enum acpi_irq_model_id acpi_irq_model = ACPI_IRQ_MODEL_GIC;
+
 /*
  * __acpi_map_table() will be called before page_init(), so early_ioremap()
  * or early_memremap() should be called here to for ACPI table mapping.
@@ -218,6 +224,73 @@ void __init acpi_init_cpus(void)
        pr_info("%d CPUs enabled, %d CPUs total\n", enabled_cpus, total_cpus);
 }
 
+int acpi_gsi_to_irq(u32 gsi, unsigned int *irq)
+{
+       *irq = irq_find_mapping(NULL, gsi);
+
+       return 0;
+}
+EXPORT_SYMBOL_GPL(acpi_gsi_to_irq);
+
+/*
+ * success: return IRQ number (>0)
+ * failure: return =< 0
+ */
+int acpi_register_gsi(struct device *dev, u32 gsi, int trigger, int polarity)
+{
+       unsigned int irq;
+       unsigned int irq_type;
+
+       /*
+        * ACPI have no bindings to indicate SPI or PPI, so we
+        * use different mappings from DT in ACPI.
+        *
+        * For FDT
+        * PPI interrupt: in the range [0, 15];
+        * SPI interrupt: in the range [0, 987];
+        *
+        * For ACPI, GSI should be unique so using
+        * the hwirq directly for the mapping:
+        * PPI interrupt: in the range [16, 31];
+        * SPI interrupt: in the range [32, 1019];
+        */
+
+       if (trigger == ACPI_EDGE_SENSITIVE &&
+                               polarity == ACPI_ACTIVE_LOW)
+               irq_type = IRQ_TYPE_EDGE_FALLING;
+       else if (trigger == ACPI_EDGE_SENSITIVE &&
+                               polarity == ACPI_ACTIVE_HIGH)
+               irq_type = IRQ_TYPE_EDGE_RISING;
+       else if (trigger == ACPI_LEVEL_SENSITIVE &&
+                               polarity == ACPI_ACTIVE_LOW)
+               irq_type = IRQ_TYPE_LEVEL_LOW;
+       else if (trigger == ACPI_LEVEL_SENSITIVE &&
+                               polarity == ACPI_ACTIVE_HIGH)
+               irq_type = IRQ_TYPE_LEVEL_HIGH;
+       else
+               irq_type = IRQ_TYPE_NONE;
+
+       /*
+        * Since only one GIC is supported in ACPI 5.0, we can
+        * create mapping refer to the default domain
+        */
+       irq = irq_create_mapping(NULL, gsi);
+       if (!irq)
+               return irq;
+
+       /* Set irq type if specified and different than the current one */
+       if (irq_type != IRQ_TYPE_NONE &&
+               irq_type != irq_get_trigger_type(irq))
+               irq_set_irq_type(irq, irq_type);
+       return irq;
+}
+EXPORT_SYMBOL_GPL(acpi_register_gsi);
+
+void acpi_unregister_gsi(u32 gsi)
+{
+}
+EXPORT_SYMBOL_GPL(acpi_unregister_gsi);
+
 static int __init acpi_parse_fadt(struct acpi_table_header *table)
 {
        struct acpi_table_fadt *fadt = (struct acpi_table_fadt *)table;

diff --git a/drivers/acpi/bus.c b/drivers/acpi/bus.c
index 8b67bd0..c412fdb 100644 (file)
--- a/drivers/acpi/bus.c
+++ b/drivers/acpi/bus.c
@@ -448,6 +448,9 @@ static int __init acpi_bus_init_irq(void)
        case ACPI_IRQ_MODEL_IOSAPIC:
                message = "IOSAPIC";
                break;
+       case ACPI_IRQ_MODEL_GIC:
+               message = "GIC";
+               break;
        case ACPI_IRQ_MODEL_PLATFORM:
                message = "platform specific model";
                break;

diff --git a/include/linux/acpi.h b/include/linux/acpi.h
index 6ec33c5..de4e86f 100644 (file)
--- a/include/linux/acpi.h
+++ b/include/linux/acpi.h
@@ -73,6 +73,7 @@ enum acpi_irq_model_id {
        ACPI_IRQ_MODEL_IOAPIC,
        ACPI_IRQ_MODEL_IOSAPIC,
        ACPI_IRQ_MODEL_PLATFORM,
+       ACPI_IRQ_MODEL_GIC,
        ACPI_IRQ_MODEL_COUNT
 };