[PATCH 08/10] riscv: Update linker scripts to ensure appended device tree is aligned

[Tom Rini]

With commit 0535e46d55d7 ("scripts/dtc: Update to upstream version
v1.7.2-35-g52f07dcca47c") it is now a fatal error to U-Boot if our
device tree is not 8-byte aligned. In commit f613a6e15ef7 ("ARM: OMAP2+:
Pad SPL binary to 8-byte alignment before DTB") Beleswar Padhi explains
that we must have ALIGN(x) statements inside of a section to ensure that
padding is included and not simply that the linker address counter is
incremented. To that end, this patch:
- Aligns the final section before _end (for U-Boot) or _image_binary_end
  (for xPL phases) by 8-bytes by adding '. = ALIGN(8);' to the final
  section before the symbol.
- Remove a now-spurious  '. = ALIGN(x);' statement that was intended to
  provide the above alignments.
- Ensure that we do have alignment by adding an ASSERT so that when not
  aligned we fail to link (and explain why).

Signed-off-by: Tom Rini <trini at konsulko.com>
---
Cc: Ilias Apalodimas <ilias.apalodimas at linaro.org>
Cc: Leo <ycliang at andestech.com>
Cc: Marek Vasut <marek.vasut+renesas at mailbox.org>
Cc: Richard Henderson <richard.henderson at linaro.org>
Cc: Rick Chen <rick at andestech.com>
---
 arch/riscv/cpu/u-boot-spl.lds | 4 ++++
 arch/riscv/cpu/u-boot.lds     | 5 +++--
 2 files changed, 7 insertions(+), 2 deletions(-)

diff --git a/arch/riscv/cpu/u-boot-spl.lds b/arch/riscv/cpu/u-boot-spl.lds
index 0717833df556..35de28db8f3a 100644
--- a/arch/riscv/cpu/u-boot-spl.lds
+++ b/arch/riscv/cpu/u-boot-spl.lds
@@ -43,6 +43,7 @@ SECTIONS
 		__binman_sym_start = .;
 		KEEP(*(SORT(.binman_sym*)));
 		__binman_sym_end = .;
+		. = ALIGN(8);
 	} > .spl_mem
 
 	_end = .;
@@ -56,3 +57,6 @@ SECTIONS
 		__bss_end = .;
 	} > .bss_mem
 }
+
+ASSERT(_image_binary_end % 8 == 0, \
+       "_image_binary_end must be 8-byte aligned for device tree");
diff --git a/arch/riscv/cpu/u-boot.lds b/arch/riscv/cpu/u-boot.lds
index b11ea8b56d25..c299c00fa298 100644
--- a/arch/riscv/cpu/u-boot.lds
+++ b/arch/riscv/cpu/u-boot.lds
@@ -73,10 +73,9 @@ SECTIONS
 		__dyn_sym_start = .;
 		*(.dynsym)
 		__dyn_sym_end = .;
+		. = ALIGN(8);
 	}
 
-	. = ALIGN(8);
-
 	_end = .;
 
 	.bss : {
@@ -86,3 +85,5 @@ SECTIONS
 		__bss_end = .;
 	}
 }
+
+ASSERT(_end % 8 == 0, "_end must be 8-byte aligned for device tree");
-- 
2.43.0