libsel4platsupport: Add mini IRQ interface
The new mini IRQ interface covers the common use case where there's only
a few interrupts to manage and these can fit into a single
notification's badge space. This also avoids the unneeded complexity
that the standard IRQ interface offers.
diff --git a/libsel4platsupport/include/sel4platsupport/irq.h b/libsel4platsupport/include/sel4platsupport/irq.h
index d0426e3..2d40c79 100644
--- a/libsel4platsupport/include/sel4platsupport/irq.h
+++ b/libsel4platsupport/include/sel4platsupport/irq.h
@@ -39,10 +39,12 @@
* notification instance */
#define MAX_INTERRUPTS_TO_NOTIFICATIONS seL4_BadgeBits
+#define MINI_IRQ_INTERFACE_NTFN_ID 0
+
typedef int ntfn_id_t;
/*
- * NOTE: This implementation of the platsuport IRQ interface is not thread-safe.
+ * NOTE: These implementations of the platsupport IRQ interface is not thread-safe.
*/
/*
@@ -66,6 +68,32 @@
ps_malloc_ops_t *malloc_ops);
/*
+ * Initialises a 'mini' IRQ interface.
+ *
+ * It functions similar to the larger IRQ interface except that this interface
+ * only manages one notification. This is useful for situations in which you
+ * have an application which manages only a few devices and do not want the
+ * extra features like being able to pair specific interrupts with specific
+ * notifications and possibly use specific bits of a notification's badge
+ * space.
+ *
+ * Only functions 'sel4platsupport_irq_(handle/wait/poll)' can be used with
+ * this interface.
+ *
+ * You can expect the notification ID of this interface to be
+ * 'MINI_IRQ_INTERFACE_NTFN_ID'.
+ *
+ * @param irq_ops Interface to fill in
+ * @param vka A VKA interface that must remain valid for the lifetime of the interface
+ * @param simple A simple interface that must remain valid for the lifetime of the interface
+ * @param malloc_ops Malloc interface that is used to allocate memory for the IRQ interface
+ * @param ntfn Notification that the IRQ interface can used to pair interrupts with
+ * @param usable_mask Mask of bits that can be used for badging
+ */
+int sel4platsupport_new_mini_irq_ops(ps_irq_ops_t *irq_ops, vka_t *vka, simple_t *simple,
+ ps_malloc_ops_t *malloc_ops, seL4_CPtr ntfn, seL4_Word usable_mask);
+
+/*
* The following functions are not intended to be used by drivers.
*
* They are intended to be used by the applications which wrap around the drivers.
diff --git a/libsel4platsupport/src/irq.c b/libsel4platsupport/src/irq.c
index fef4948..f7bbc73 100644
--- a/libsel4platsupport/src/irq.c
+++ b/libsel4platsupport/src/irq.c
@@ -30,6 +30,11 @@
#define UNPAIRED_ID -1
#define UNALLOCATED_BADGE_INDEX -1
+typedef enum irq_iface_type {
+ STANDARD_IFACE,
+ MINI_IFACE
+} irq_iface_type_t;
+
typedef struct {
/* These are always non-empty if this particular IRQ ID is in use */
bool allocated;
@@ -63,6 +68,7 @@
} ntfn_entry_t;
typedef struct {
+ irq_iface_type_t iface_type;
size_t num_registered_irqs;
size_t num_allocated_ntfns;
@@ -343,7 +349,7 @@
}
static irq_cookie_t *new_irq_ops_common(vka_t *vka, simple_t *simple, irq_interface_config_t irq_config,
- ps_malloc_ops_t *malloc_ops)
+ ps_malloc_ops_t *malloc_ops, irq_iface_type_t iface_type)
{
int err = 0;
@@ -393,6 +399,7 @@
goto error;
}
+ cookie->iface_type = iface_type;
cookie->simple = simple;
cookie->vka = vka;
cookie->malloc_ops = malloc_ops;
@@ -484,6 +491,29 @@
return irq_register_common(irq_cookie, irq, callback, callback_data);
}
+/* The register function for the mini IRQ interface */
+static irq_id_t sel4platsupport_irq_register_mini(void *cookie, ps_irq_t irq, irq_callback_fn_t callback,
+ void *callback_data)
+{
+ irq_cookie_t *irq_cookie = cookie;
+
+ irq_id_t assigned_id = irq_register_common(irq_cookie, irq, callback, callback_data);
+ if (assigned_id < 0) {
+ /* Contains the error code if < 0 */
+ return assigned_id;
+ }
+
+ /* Pair this IRQ with the only notification */
+ int error = irq_set_ntfn_common(irq_cookie, MINI_IRQ_INTERFACE_NTFN_ID, assigned_id, NULL);
+ if (error) {
+ ZF_LOGF_IF(sel4platsupport_irq_unregister(irq_cookie, assigned_id),
+ "Failed to clean-up a failed operation");
+ return error;
+ }
+
+ return assigned_id;
+}
+
static int sel4platsupport_irq_acknowledge(void *ack_data)
{
if (!ack_data) {
@@ -531,7 +561,7 @@
return -EINVAL;
}
- irq_cookie_t *cookie = new_irq_ops_common(vka, simple, irq_config, malloc_ops);
+ irq_cookie_t *cookie = new_irq_ops_common(vka, simple, irq_config, malloc_ops, STANDARD_IFACE);
if (!cookie) {
return -ENOMEM;
}
@@ -544,6 +574,40 @@
return 0;
}
+int sel4platsupport_new_mini_irq_ops(ps_irq_ops_t *irq_ops, vka_t *vka, simple_t *simple,
+ ps_malloc_ops_t *malloc_ops, seL4_CPtr ntfn, seL4_Word usable_mask)
+{
+ if (!irq_ops || !vka || !simple || !malloc_ops || !usable_mask) {
+ return -EINVAL;
+ }
+
+ if (ntfn == seL4_CapNull) {
+ return -EINVAL;
+ }
+
+ /* Get the number of bits that we can use in the badge,
+ * this is the amount of interrupts that can be registered at a given time */
+ size_t bits_in_mask = POPCOUNTL(usable_mask);
+
+ /* max_ntfn_ids is kinda irrelevant in the mini interface, but set it anyway */
+ irq_interface_config_t irq_config = { .max_irq_ids = bits_in_mask, .max_ntfn_ids = 1 };
+
+ irq_cookie_t *cookie = new_irq_ops_common(vka, simple, irq_config, malloc_ops, MINI_IFACE);
+ if (!cookie) {
+ return -ENOMEM;
+ }
+
+ /* Fill in the actual IRQ ops structure now */
+ irq_ops->cookie = (void *) cookie;
+ irq_ops->irq_register_fn = sel4platsupport_irq_register_mini;
+ irq_ops->irq_unregister_fn = sel4platsupport_irq_unregister;
+
+ /* Provide the ntfn */
+ provide_ntfn_common(cookie, ntfn, usable_mask, MINI_IRQ_INTERFACE_NTFN_ID);
+
+ return 0;
+}
+
ntfn_id_t sel4platsupport_irq_provide_ntfn(ps_irq_ops_t *irq_ops, seL4_CPtr ntfn, seL4_Word usable_mask)
{
if (!irq_ops || ntfn == seL4_CapNull || !usable_mask) {
@@ -552,6 +616,11 @@
irq_cookie_t *irq_cookie = irq_ops->cookie;
+ if (irq_cookie->iface_type == MINI_IFACE) {
+ ZF_LOGE("Trying to use %s with the mini IRQ Interface", __func__);
+ return -EPERM;
+ }
+
if (check_ntfn_id_all_allocated(irq_cookie)) {
return -EMFILE;
}
@@ -575,6 +644,11 @@
irq_cookie_t *irq_cookie = irq_ops->cookie;
+ if (irq_cookie->iface_type == MINI_IFACE) {
+ ZF_LOGE("Trying to use %s with the mini IRQ Interface", __func__);
+ return -EPERM;
+ }
+
if (check_ntfn_id_all_allocated(irq_cookie)) {
return -EMFILE;
}
@@ -597,6 +671,11 @@
irq_cookie_t *irq_cookie = irq_ops->cookie;
+ if (irq_cookie->iface_type == MINI_IFACE) {
+ ZF_LOGE("Trying to use %s with the mini IRQ Interface", __func__);
+ return -EPERM;
+ }
+
if (!check_ntfn_id_is_valid(irq_cookie, ntfn_id)) {
return -EINVAL;
}
@@ -648,6 +727,11 @@
irq_cookie_t *irq_cookie = irq_ops->cookie;
+ if (irq_cookie->iface_type == MINI_IFACE) {
+ ZF_LOGE("Trying to use %s with the mini IRQ Interface", __func__);
+ return -EPERM;
+ }
+
if (!check_ntfn_id_is_valid(irq_cookie, ntfn_id) ||
!check_ntfn_id_is_allocated(irq_cookie, ntfn_id)) {
return -EINVAL;
@@ -669,6 +753,11 @@
irq_cookie_t *irq_cookie = irq_ops->cookie;
+ if (irq_cookie->iface_type == MINI_IFACE) {
+ ZF_LOGE("Trying to use %s with the mini IRQ Interface", __func__);
+ return -EPERM;
+ }
+
if (!check_irq_id_is_valid(irq_cookie, irq_id) ||
!check_irq_id_is_allocated(irq_cookie, irq_id)) {
return -EINVAL;
