From: Wei Chen <wei.chen@xxxxxxx>
This helper will be used very frequently for devices to
get their interrupts.
Signed-off-by: Wei Chen <wei.chen@xxxxxxx>
Signed-off-by: Jia He <justin.he@xxxxxxx>
---
plat/drivers/include/ofw/fdt.h | 20 ++++++++++++++++++++
plat/drivers/ofw/fdt.c | 33 +++++++++++++++++++++++++++++++++
2 files changed, 53 insertions(+)
diff --git a/plat/drivers/include/ofw/fdt.h b/plat/drivers/include/ofw/fdt.h
index aaa32c6..50df70d 100644
--- a/plat/drivers/include/ofw/fdt.h
+++ b/plat/drivers/include/ofw/fdt.h
@@ -138,4 +138,24 @@ int fdt_get_address(const void *fdt, int nodeoffset,
uint32_t index,
*/
int fdt_node_offset_by_compatible_list(const void *fdt, int startoffset,
const char * const compatibles[]);
+
+/**
+ * fdt_get_interrupt - retrieve device interrupt of a given index
+ * @fdt: pointer to the device tree blob
+ * @nodeoffset: offset of the node to find the address for
+ * @index: the index of interrupt we want to retrieve
+ * @size: interrupt cell size in fdt32_t
+ * @prop: return the pointer to property
+ * returns:
+ * 0 on success , < 0 on failed
+ * -FDT_ERR_NOTFOUND, node does not have named property
+ * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
+ * -FDT_ERR_BADMAGIC,
+ * -FDT_ERR_BADVERSION,
+ * -FDT_ERR_BADSTATE,
+ * -FDT_ERR_BADSTRUCTURE,
+ * -FDT_ERR_TRUNCATED, standard meanings
+ */
+int fdt_get_interrupt(const void *fdt, int nodeoffset,
+ uint32_t index, int *size, fdt32_t **prop);
#endif
diff --git a/plat/drivers/ofw/fdt.c b/plat/drivers/ofw/fdt.c
index 683dd60..795e77a 100644
--- a/plat/drivers/ofw/fdt.c
+++ b/plat/drivers/ofw/fdt.c
@@ -277,3 +277,36 @@ int fdt_node_offset_by_compatible_list(const void *fdt,
int startoffset,
return -FDT_ERR_NOTFOUND;
}
+
+int fdt_get_interrupt(const void *fdt, int nodeoffset,
+ uint32_t index, int *size, fdt32_t **prop)
+{
+ int nintr, len, term_size;
+ const void *regs;
+
+ UK_ASSERT(size && prop);
+
+ nintr = fdt_interrupt_cells(fdt, nodeoffset);
+ if (nintr < 0 || nintr >= FDT_MAX_NCELLS)
+ return -FDT_ERR_BADNCELLS;
+
+ /* "interrupts-extended" is not supported */
+ regs = fdt_getprop(fdt, nodeoffset, "interrupts-extended", &len);
+ if (regs) {
+ uk_pr_warn("interrupts multiple parents is not supported\n");
+ return -FDT_ERR_INTERNAL;
+ }
+
+ /*
+ * Interrupt content must cover the index specific irq information.
+ */
+ regs = fdt_getprop(fdt, nodeoffset, "interrupts", &len);
+ term_size = sizeof(fdt32_t) * nintr;
+ if (regs == NULL || (uint32_t)len < term_size * (index + 1))
+ return -FDT_ERR_NOTFOUND;
+
+ *size = nintr;
+ *prop = (fdt32_t *)(regs + term_size * index);
+
+ return 0;
+}
