Re: [PATCH 3/5] irqchip/gic-v2: Parse and export virtual GIC information

[Julien Grall]

On 08/02/16 18:30, Marc Zyngier wrote:
Julien,

Hi Marc,

On 08/02/16 16:47, Julien Grall wrote:

[...]

+static void __init gic_of_setup_kvm_info(struct device_node *node)
+{
+       int ret;
+       struct resource r;
+       unsigned int irq;
+
+       gic_v2_kvm_info.type = GIC_V2;
+
+       irq = irq_of_parse_and_map(node, 0);
+       if (!irq)
+               gic_v2_kvm_info.maint_irq = -1;

Please don't do that. 0 *is* the value for an invalid interrupt, and
this is what you should expose here. Same for GICv3.

I decided to use -1, because the function acpi_register_gsi is returning 
a negative value when an error occurred.

AFAICT, returning 0 would be a valid value for acpi_register_gsi.

+       else
+               gic_v2_kvm_info.maint_irq = irq;
+
+       ret = of_address_to_resource(node, 2, &r);
+       if (!ret) {
+               gic_v2_kvm_info.vctrl_base = r.start;
+               gic_v2_kvm_info.vctrl_size = resource_size(&r);
+       }
+
+       ret = of_address_to_resource(node, 3, &r);
+       if (!ret) {
+               if (!PAGE_ALIGNED(r.start))
+                       pr_warn("GICV physical address 0x%llx not page 
aligned\n",
+                               (unsigned long long)r.start);
+               else if (!PAGE_ALIGNED(resource_size(&r)))
+                       pr_warn("GICV size 0x%llx not a multiple of page size 
0x%lx\n",
+                               (unsigned long long)resource_size(&r),
+                               PAGE_SIZE);
+               else {
+                       gic_v2_kvm_info.vcpu_base = r.start;
+                       gic_v2_kvm_info.vcpu_size = resource_size(&r);

This tends to make me think that this should actually be a proper
resource, and not a set of arbitrary fields.

I will give a look.

[..]

@@ -1270,6 +1338,12 @@ gic_acpi_parse_madt_cpu(struct acpi_subtable_header 
*header,
                return -EINVAL;

        cpu_phy_base = gic_cpu_base;
+       acpi_data.maint_irq = processor->vgic_interrupt;
+       acpi_data.maint_irq_mode = (processor->flags & ACPI_MADT_VGIC_IRQ_MODE) 
?
+                                   ACPI_EDGE_SENSITIVE : ACPI_LEVEL_SENSITIVE;
+       acpi_data.vctrl_base = processor->gich_base_address;
+       acpi_data.vcpu_base = processor->gicv_base_address;
+

Maybe you can now move all the ACPI data into this acpi_data structure?
This would allow for slightly less clutter...

Good idea, I will do it in the next version.

[...]


Thanks,

Regards,

--
Julien Grall