[OE-core] [meta-oe][PATCH RESEND] devicetree.bbclass: don't pad DT overlays

[lucaceresoli77 at gmail.com]

From: Luca Ceresoli <luca at lucaceresoli.net>

By default the devicetree class adds padding to the generated .dtb
files, which can be needed by the bootloader. However it also pads
.dtbo files, which is not useful.

Don't apply padding to the overlay devicetrees.

To achieve this:

 * move "-p ${DT_PADDING_SIZE}" to a new variable, DTB_BFLAGS (B for
   "base")
 * add "-p 0" to DTC_OFLAGS to disable padding for overlays

Cc: Nathan Rossi <nathan at nathanrossi.com>
Signed-off-by: Luca Ceresoli <luca at lucaceresoli.net>
---

Resending from a gmail account due to ongoing issues between my
provider and lists.openembedded.org.

---
 meta/classes/devicetree.bbclass | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/meta/classes/devicetree.bbclass b/meta/classes/devicetree.bbclass
index dbc83f2a1d98..8fe5a5ed795c 100644
--- a/meta/classes/devicetree.bbclass
+++ b/meta/classes/devicetree.bbclass
@@ -55,9 +55,10 @@ DT_RESERVED_MAP ??= "8"
 DT_BOOT_CPU[doc] = "The boot cpu, defaults to 0"
 DT_BOOT_CPU ??= "0"
 
-DTC_FLAGS ?= "-R ${DT_RESERVED_MAP} -p ${DT_PADDING_SIZE} -b ${DT_BOOT_CPU}"
+DTC_FLAGS ?= "-R ${DT_RESERVED_MAP} -b ${DT_BOOT_CPU}"
 DTC_PPFLAGS ?= "-nostdinc -undef -D__DTS__ -x assembler-with-cpp"
-DTC_OFLAGS ?= "-@ -H epapr"
+DTC_BFLAGS ?= "-p ${DT_PADDING_SIZE}"
+DTC_OFLAGS ?= "-p 0 -@ -H epapr"
 
 python () {
     if d.getVar("KERNEL_INCLUDE"):
@@ -106,6 +107,8 @@ def devicetree_compile(dtspath, includes, d):
     dtcargs = ["dtc"] + (d.getVar("DTC_FLAGS") or "").split()
     if isoverlay:
         dtcargs += (d.getVar("DTC_OFLAGS") or "").split()
+    else:
+        dtcargs += (d.getVar("DTC_BFLAGS") or "").split()
     for i in includes:
         dtcargs += ["-i", i]
     dtcargs += ["-o", "{0}.{1}".format(dtname, "dtbo" if isoverlay else "dtb")]
-- 
2.17.1