elf loader: The rproc elf loading problem

The elf loader assumes that the last ELF program segment will always
be a LOAD type segment. I deduce this from the fact that the elf_load()
function, when loading the remote ELF sections during the
RPROC_LOADER_READY_TO_LOAD stage, compares the last load segment num
to the total ELF sections to determine if the loading is complete and
it can move to the next stage RPROC_LOADER_POST_DATA_LOAD. If the last
program segment in the ELF is not of type LOAD, the last loaded LOAD
segment never equals total ELF sections. This creates an error
condition and the firmware loading fails. This patch fixes this issue
by comparing the last loaded LOAD segment number with the max LOAD
segment number in the ELF.

Signed-off-by: Umair Khan <umair_khan@mentor.com>

lib/remoteproc/elf_loader.c

@@ -571,20 +571,24 @@ int elf_load(struct remoteproc *rproc,
 		nsegment = *load_state & ELF_NEXT_SEGMENT_MASK;
 		phdr = elf_next_load_segment(*img_info, &nsegment, da,
 					     noffset, &nsize, &nsegmsize);
-		if (!phdr) {
-			metal_log(METAL_LOG_DEBUG, "cannot find more segment\r\n");
-			*load_state = (*load_state & (~ELF_NEXT_SEGMENT_MASK)) |
-				      (nsegment & ELF_NEXT_SEGMENT_MASK);
-			return *load_state;
-		}
+
+		phnums = elf_phnum(*img_info);
+		if (phdr) {
 		*nlen = nsize;
 		*nmemsize = nsegmsize;
-		phnums = elf_phnum(*img_info);
-		metal_log(METAL_LOG_DEBUG, "segment: %d, total segs %d\r\n",
-			  nsegment, phnums);
+			metal_log(METAL_LOG_DEBUG, "segment: %d, total segs %d\r\n", nsegment, phnums);
+		}
+
 		if (nsegment == phnums) {
+			if (phdr) {
 			*load_state = (*load_state & (~RPROC_LOADER_MASK)) |
 				      RPROC_LOADER_POST_DATA_LOAD;
+			} else {
+ 			        metal_log(METAL_LOG_DEBUG, "no more segment to load\r\n");
+				*load_state = (*load_state & (~RPROC_LOADER_MASK)) |
+				      RPROC_LOADER_LOAD_COMPLETE;
+				      *da = RPROC_LOAD_ANYADDR;
+			}
 		}
 		*load_state = (*load_state & (~ELF_NEXT_SEGMENT_MASK)) |
 			      (nsegment & ELF_NEXT_SEGMENT_MASK);