remoteproc: Introduce custom dump function for each remoteproc segment

Introduce custom dump function and private data per remoteproc dump
segment. The dump function is responsible for filling the device memory
segment associated with coredump

Signed-off-by: Sibi Sankar <sibis@codeaurora.org>
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>

drivers/remoteproc/remoteproc_core.c

@@ -1508,14 +1508,18 @@ static void rproc_coredump(struct rproc *rproc)
 		phdr->p_flags = PF_R | PF_W | PF_X;
 		phdr->p_align = 0;
 
-		ptr = rproc_da_to_va(rproc, segment->da, segment->size);
-		if (!ptr) {
-			dev_err(&rproc->dev,
-				"invalid coredump segment (%pad, %zu)\n",
-				&segment->da, segment->size);
-			memset(data + offset, 0xff, segment->size);
+		if (segment->dump) {
+			segment->dump(rproc, segment, data + offset);
 		} else {
-			memcpy(data + offset, ptr, segment->size);
+			ptr = rproc_da_to_va(rproc, segment->da, segment->size);
+			if (!ptr) {
+				dev_err(&rproc->dev,
+					"invalid coredump segment (%pad, %zu)\n",
+					&segment->da, segment->size);
+				memset(data + offset, 0xff, segment->size);
+			} else {
+				memcpy(data + offset, ptr, segment->size);
+			}
 		}
 
 		offset += phdr->p_filesz;

include/linux/remoteproc.h

@@ -412,6 +412,9 @@ enum rproc_crash_type {
  * @node:	list node related to the rproc segment list
  * @da:		device address of the segment
  * @size:	size of the segment
+ * @priv:	private data associated with the dump_segment
+ * @dump:	custom dump function to fill device memory segment associated
+ *		with coredump
  */
 struct rproc_dump_segment {
 	struct list_head node;
@@ -419,6 +422,9 @@ struct rproc_dump_segment {
 	dma_addr_t da;
 	size_t size;
 
+	void *priv;
+	void (*dump)(struct rproc *rproc, struct rproc_dump_segment *segment,
+		     void *dest);
 	loff_t offset;
 };