On 2014-8-19 2:34, Sudeep Holla wrote:

On 04/08/14 16:28, Hanjun Guo wrote:

quoted

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.

Originally-by: Amit Daniel Kachhap [off-list ref]
Signed-off-by: Hanjun Guo <redacted>
---
  arch/arm64/kernel/acpi.c |   73 ++++++++++++++++++++++++++++++++++++++++++++++
  drivers/acpi/bus.c       |    3 ++
  include/linux/acpi.h     |    1 +
  3 files changed, 77 insertions(+)

diff --git a/arch/arm64/kernel/acpi.c b/arch/arm64/kernel/acpi.c
index ac7ab34..621ced8 100644
--- a/arch/arm64/kernel/acpi.c
+++ b/arch/arm64/kernel/acpi.c

@@ -34,6 +34,12 @@ EXPORT_SYMBOL(acpi_pci_disabled);
  static int enabled_cpus;    /* Processors (GICC) with enabled flag in MADT */

  /*
+ * 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.
   */

@@ -169,6 +175,73 @@ static int __init

acpi_parse_madt_gic_cpu_interface_entries(void)
      return 0;
  }

+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);
+

Not sure if acpi_gsi_to_irq and acpi_{,un}register_gsi belong here.
These are GIC specific and should belong to GIC driver IMO.

I think we can keep them here as GSI is ACPI specific and they are
not GIC init related.

Thanks
Hanjun