[RFT v2 22/24] x86, irq: Use hierarchy irqdomain to manage DMAR interrupts

From: Jiang Liu
Date: Fri Sep 26 2014 - 10:03:24 EST


Enhance DMAR code to support hierarchy irqdomain, it helps to make
the architecture more clear.

Signed-off-by: Jiang Liu <jiang.liu@xxxxxxxxxxxxxxx>
---
arch/x86/include/asm/hw_irq.h | 7 +++
arch/x86/kernel/apic/msi.c | 129 +++++++++++++++++++++++++++++++----------
2 files changed, 106 insertions(+), 30 deletions(-)

diff --git a/arch/x86/include/asm/hw_irq.h b/arch/x86/include/asm/hw_irq.h
index a5d3b1c46b30..7ed68ce5929a 100644
--- a/arch/x86/include/asm/hw_irq.h
+++ b/arch/x86/include/asm/hw_irq.h
@@ -121,6 +121,7 @@ enum irq_alloc_type {
X86_IRQ_ALLOC_TYPE_HPET,
X86_IRQ_ALLOC_TYPE_MSI,
X86_IRQ_ALLOC_TYPE_MSIX,
+ X86_IRQ_ALLOC_TYPE_DMAR,
};

struct irq_alloc_info {
@@ -149,6 +150,12 @@ struct irq_alloc_info {
u32 ioapic_polarity : 1;
};
#endif
+#ifdef CONFIG_DMAR_TABLE
+ struct {
+ int dmar_id;
+ void *dmar_data;
+ };
+#endif
};
};

diff --git a/arch/x86/kernel/apic/msi.c b/arch/x86/kernel/apic/msi.c
index 08b6d1987ea6..409638b3918a 100644
--- a/arch/x86/kernel/apic/msi.c
+++ b/arch/x86/kernel/apic/msi.c
@@ -69,6 +69,9 @@ static void msi_update_msg(struct msi_msg *msg, struct irq_data *irq_data)
msg->data |= MSI_DATA_VECTOR(cfg->vector);
msg->address_lo &= ~MSI_ADDR_DEST_ID_MASK;
msg->address_lo |= MSI_ADDR_DEST_ID(cfg->dest_apicid);
+ if (x2apic_enabled())
+ msg->address_hi = MSI_ADDR_BASE_HI |
+ MSI_ADDR_EXT_DEST_ID(cfg->dest_apicid);
}

static bool msi_irq_remapped(struct irq_data *irq_data)
@@ -298,58 +301,124 @@ static int
dmar_msi_set_affinity(struct irq_data *data, const struct cpumask *mask,
bool force)
{
- struct irq_cfg *cfg = irqd_cfg(data);
- unsigned int dest, irq = data->irq;
+ struct irq_data *parent = data->parent_data;
struct msi_msg msg;
int ret;

- ret = apic_set_affinity(data, mask, &dest);
- if (ret)
- return ret;
-
- dmar_msi_read(irq, &msg);
-
- msg.data &= ~MSI_DATA_VECTOR_MASK;
- msg.data |= MSI_DATA_VECTOR(cfg->vector);
- msg.address_lo &= ~MSI_ADDR_DEST_ID_MASK;
- msg.address_lo |= MSI_ADDR_DEST_ID(dest);
- msg.address_hi = MSI_ADDR_BASE_HI | MSI_ADDR_EXT_DEST_ID(dest);
-
- dmar_msi_write(irq, &msg);
+ ret = parent->chip->irq_set_affinity(parent, mask, force);
+ if (ret >= 0) {
+ dmar_msi_read(data->irq, &msg);
+ msi_update_msg(&msg, data);
+ dmar_msi_write(data->irq, &msg);
+ }

- return IRQ_SET_MASK_OK_NOCOPY;
+ return ret;
}

static struct irq_chip dmar_msi_type = {
.name = "DMAR_MSI",
.irq_unmask = dmar_msi_unmask,
.irq_mask = dmar_msi_mask,
- .irq_ack = apic_ack_edge,
+ .irq_ack = irq_chip_ack_parent,
.irq_set_affinity = dmar_msi_set_affinity,
- .irq_retrigger = apic_retrigger_irq,
+ .irq_retrigger = irq_chip_retrigger_hierarchy,
};

-int dmar_alloc_hwirq(int id, int node, void *arg)
+static int dmar_domain_alloc(struct irq_domain *domain, unsigned int virq,
+ unsigned int nr_irqs, void *arg)
+{
+ struct irq_alloc_info *info = arg;
+ int ret;
+
+ if (nr_irqs > 1 || !info || info->type != X86_IRQ_ALLOC_TYPE_DMAR)
+ return -EINVAL;
+ if (irq_find_mapping(domain, info->dmar_id)) {
+ pr_warn("IRQ for DMAR%d already exists.\n", info->dmar_id);
+ return -EEXIST;
+ }
+
+ ret = irq_domain_alloc_irqs_parent(domain, virq, nr_irqs, arg);
+ if (ret >= 0) {
+ irq_domain_set_hwirq_and_chip(domain, virq, info->dmar_id,
+ &dmar_msi_type, NULL);
+ irq_set_handler_data(virq, info->dmar_data);
+ __irq_set_handler(virq, handle_edge_irq, 0, "edge");
+ }
+
+ return ret;
+}
+
+static void dmar_domain_free(struct irq_domain *domain, unsigned int virq,
+ unsigned int nr_irqs)
+{
+ BUG_ON(nr_irqs > 1);
+ msi_reset_irq_data_and_handler(domain, virq);
+ irq_domain_free_irqs_parent(domain, virq, nr_irqs);
+}
+
+static int dmar_domain_activate(struct irq_domain *domain,
+ struct irq_data *irq_data)
+{
+ struct msi_msg msg;
+
+ native_compose_msi_msg(irqd_cfg(irq_data), &msg);
+ dmar_msi_write(irq_data->irq, &msg);
+
+ return 0;
+}
+
+static int dmar_domain_deactivate(struct irq_domain *domain,
+ struct irq_data *irq_data)
{
- int irq;
struct msi_msg msg;

- irq = irq_domain_alloc_irqs(NULL, 1, node, NULL);
- if (irq > 0) {
- irq_set_handler_data(irq, arg);
- irq_set_chip_and_handler_name(irq, &dmar_msi_type,
- handle_edge_irq, "edge");
- native_compose_msi_msg(irq_cfg(irq), &msg);
- dmar_msi_write(irq, &msg);
+ memset(&msg, 0, sizeof(msg));
+ dmar_msi_write(irq_data->irq, &msg);
+
+ return 0;
+}
+
+static struct irq_domain_ops dmar_domain_ops = {
+ .alloc = dmar_domain_alloc,
+ .free = dmar_domain_free,
+ .activate = dmar_domain_activate,
+ .deactivate = dmar_domain_deactivate,
+};
+
+static struct irq_domain *dmar_get_irq_domain(void)
+{
+ static struct irq_domain *dmar_domain;
+ static DEFINE_MUTEX(dmar_lock);
+
+ mutex_lock(&dmar_lock);
+ if (dmar_domain == NULL) {
+ dmar_domain = irq_domain_add_tree(NULL, &dmar_domain_ops, NULL);
+ if (dmar_domain)
+ dmar_domain->parent = x86_vector_domain;
}
+ mutex_unlock(&dmar_lock);
+
+ return dmar_domain;
+}
+
+int dmar_alloc_hwirq(int id, int node, void *arg)
+{
+ struct irq_domain *domain = dmar_get_irq_domain();
+ struct irq_alloc_info info;
+
+ if (!domain)
+ return -1;
+
+ init_irq_alloc_info(&info, NULL);
+ info.type = X86_IRQ_ALLOC_TYPE_DMAR;
+ info.dmar_id = id;
+ info.dmar_data = arg;

- return irq;
+ return irq_domain_alloc_irqs(domain, 1, node, &info);
}

void dmar_free_hwirq(int irq)
{
- irq_set_handler_data(irq, NULL);
- irq_set_handler(irq, NULL);
irq_domain_free_irqs(irq, 1);
}
#endif
--
1.7.10.4

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