The FIC supports either a (single) wired output, or generation of an MSI-X
interrupt per input (for cases where it is embedded in a PCIe device,
hence, allowing the PCIe drivers to call this API).
This patch introduces the support for allowing the configuration of MSI-X
instead of a wire interrupt.
Signed-off-by: Talel Shenhar <ta...@amazon.com>
---
drivers/irqchip/irq-al-fic.c | 48 +++++++++++++++++++++++++++++++++++++++---
include/linux/irqchip/al-fic.h | 2 ++
2 files changed, 47 insertions(+), 3 deletions(-)
diff --git a/drivers/irqchip/irq-al-fic.c b/drivers/irqchip/irq-al-fic.c
index d881d42..e49b912 100644
--- a/drivers/irqchip/irq-al-fic.c
+++ b/drivers/irqchip/irq-al-fic.c
@@ -19,6 +19,7 @@
#define AL_FIC_MASK 0x10
#define AL_FIC_CONTROL 0x28
+#define CONTROL_AUTO_CLEAR BIT(2)
#define CONTROL_TRIGGER_RISING BIT(3)
#define CONTROL_MASK_MSI_X BIT(5)
@@ -193,9 +194,11 @@ struct irq_domain *al_fic_wire_get_domain(struct al_fic
*fic)
}
EXPORT_SYMBOL_GPL(al_fic_wire_get_domain);
-static void al_fic_hw_init(struct al_fic *fic)
+static void al_fic_hw_init(struct al_fic *fic,
+ int use_msi)
{
- u32 control = CONTROL_MASK_MSI_X;
+ u32 control = (use_msi ? (CONTROL_AUTO_CLEAR | CONTROL_TRIGGER_RISING) :
+ CONTROL_MASK_MSI_X);
/* mask out all interrupts */
writel(0xFFFFFFFF, fic->base + AL_FIC_MASK);
@@ -240,7 +243,7 @@ struct al_fic *al_fic_wire_init(struct device_node *node,
fic->parent_irq = parent_irq;
fic->name = (name ?: "al-fic-wire");
- al_fic_hw_init(fic);
+ al_fic_hw_init(fic, false);
ret = al_fic_register(node, fic);
if (ret) {
@@ -260,6 +263,45 @@ struct al_fic *al_fic_wire_init(struct device_node *node,
EXPORT_SYMBOL_GPL(al_fic_wire_init);
/**
+ * al_fic_msi_x_init() - initialize and configure fic in msi-x mode
+ * @base: mmio to fic register
+ * @name: name of the fic
+ *
+ * This API will configure the fic hardware to to work in msi-x mode.
+ * msi-x fic is to be configured for fics that are embedded inside AL PCIE EP.
+ * Those kind of fic are aware of the fact that they live inside PCIE and
+ * familiar with the MSI-X table which is configured as part of
+ * pci_enable_msix_range() and friends.
+ * Interrupt can be generated based on a positive edge or level - configuration
+ * is to be determined based on connected hardware to this fic.
+ *
+ * Returns pointer to fic context or ERR_PTR in case of error.
+ */
+struct al_fic *al_fic_msi_x_init(void __iomem *base,
+ const char *name)
+{
+ struct al_fic *fic;
+
+ if (!base)
+ return ERR_PTR(-EINVAL);
+
+ fic = kzalloc(sizeof(*fic), GFP_KERNEL);
+ if (!fic)
+ return ERR_PTR(-ENOMEM);
+
+ fic->base = base;
+ fic->name = (name ?: "al-fic-full-fledged");
+
+ al_fic_hw_init(fic, true);
+
+ pr_debug("%s initialized successfully in Full-Fledged mode\n",
+ fic->name);
+
+ return fic;
+}
+EXPORT_SYMBOL_GPL(al_fic_msi_x_init);
+
+/**
* al_fic_cleanup() - free all resources allocated by fic
* @fic: pointer to fic context
*
diff --git a/include/linux/irqchip/al-fic.h b/include/linux/irqchip/al-fic.h
index 0833749..a2e89ff 100644
--- a/include/linux/irqchip/al-fic.h
+++ b/include/linux/irqchip/al-fic.h
@@ -16,6 +16,8 @@ struct al_fic *al_fic_wire_init(struct device_node *node,
void __iomem *base,
const char *name,
unsigned int parent_irq);
+struct al_fic *al_fic_msi_x_init(void __iomem *base,
+ const char *name);
int al_fic_cleanup(struct al_fic *fic);
#endif
--
2.7.4
