On Mon, Sep 15, 2014 at 05:16:21PM +0100, Jon Masters wrote:

On 09/15/2014 11:01 AM, Catalin Marinas wrote:

quoted

On Fri, Sep 12, 2014 at 03:00:12PM +0100, Hanjun Guo wrote:

quoted

diff --git a/arch/arm64/kernel/acpi.c b/arch/arm64/kernel/acpi.c
index 5b3546b..9869377 100644
--- a/arch/arm64/kernel/acpi.c
+++ b/arch/arm64/kernel/acpi.c

@@ -23,6 +23,7 @@
 #include <linux/irqdomain.h>
 #include <linux/bootmem.h>
 #include <linux/smp.h>
+#include <linux/irqchip/arm-gic-acpi.h>
 
 #include <asm/cputype.h>
 #include <asm/cpu_ops.h>

@@ -312,6 +313,28 @@ void __init acpi_boot_table_init(void)
 		pr_err("Can't find FADT or error happened during parsing FADT\n");
 }
 
+void __init acpi_gic_init(void)
+{
+	struct acpi_table_header *table;
+	acpi_status status;
+	acpi_size tbl_size;
+	int err;
+
+	status = acpi_get_table_with_size(ACPI_SIG_MADT, 0, &table, &tbl_size);
+	if (ACPI_FAILURE(status)) {
+		const char *msg = acpi_format_exception(status);
+
+		pr_err("Failed to get MADT table, %s\n", msg);
+		return;
+	}
+
+	err = gic_v2_acpi_init(table);
+	if (err)
+		pr_err("Failed to initialize GIC IRQ controller");
+
+	early_acpi_os_unmap_memory((char *)table, tbl_size);
+}

Maybe this was discussed already but why does this function need to live
under arch/arm64? Isn't the driver code more appropriate?

Well there's two halves to this, right? There's the MADT parsing/setup,
which is architecture specific, and then there's the GIC irqchip
initialization which lives under drivers.

I think it gets worse, this function is called from irqchip_init(). I
would have been slightly happier if it was called from the arm64
init_IRQ(). But putting an ARM specific GIC initialisation call in a
generic irqchip_init() just looks weird. Can we do anything better here?

Jon.

-- 
Catalin