[PATCH v23 5/6] of: Support more than one crash kernel regions for kexec -s

[Zhen Lei]

When "crashkernel=X,high" is used, there may be two crash regions:
high=crashk_res and low=crashk_low_res. But now the syscall
kexec_file_load() only add crashk_res into "linux,usable-memory-range",
this may cause the second kernel to have no available dma memory.

Fix it like kexec tool do for option -c, add both 'high' and 'low' regions
into the dtb.

Signed-off-by: Zhen Lei <thunder.leizhen@xxxxxxxxxx>
---
 drivers/of/kexec.c | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/drivers/of/kexec.c b/drivers/of/kexec.c
index b9bd1cff179388c..8d374cc552be5f2 100644
--- a/drivers/of/kexec.c
+++ b/drivers/of/kexec.c
@@ -386,6 +386,15 @@ void *of_kexec_alloc_and_setup_fdt(const struct kimage *image,
 				crashk_res.end - crashk_res.start + 1);
 		if (ret)
 			goto out;
+
+		if (crashk_low_res.end) {
+			ret = fdt_appendprop_addrrange(fdt, 0, chosen_node,
+					"linux,usable-memory-range",
+					crashk_low_res.start,
+					crashk_low_res.end - crashk_low_res.start + 1);
+			if (ret)
+				goto out;
+		}
 	}
 
 	/* add bootargs */
-- 
2.25.1