[U-Boot] [PATCH] SPL: sunxi: don't force .BSS into DRAM

Andre Przywara andre.przywara at arm.com
Thu Jun 30 02:29:12 CEST 2016


Probably due to some (ill-founded) fear of a large BSS all sunxi boards
forced their SPL BSS section into DRAM.
This only works if there is no usage of a .BSS variable before the DRAM
is initialised.
The recent inclusion of tiny-printf breaks this assumption (it has two
variables in .BSS), so any early printf (printing a number) hangs a board.
This in particular breaks the (WIP) Pine64 SPL, which at the moment links
Allwinner's libdram library, trying to print debug information:
DRAM:DRAM driver version: V1.0
DRAM Type = <hangs>

As it turns out the normal BSS size for sunxi is about 256 Bytes, so we
can happily remove the symbols and the linker script part that was
forcing the section into DRAM and let the linker naturally put it into
SRAM.
Tested on BananaPi M1 and Pine64(-SPL), also buildman sunxi was happy.

Thanks to Siarhei for providing helpful hints!

Signed-off-by: Andre Przywara <andre.przywara at arm.com>
---

(and now with the list in CC: as well) ...

 arch/arm/cpu/armv7/sunxi/u-boot-spl.lds | 4 +---
 include/configs/sunxi-common.h          | 4 ----
 2 files changed, 1 insertion(+), 7 deletions(-)

diff --git a/arch/arm/cpu/armv7/sunxi/u-boot-spl.lds b/arch/arm/cpu/armv7/sunxi/u-boot-spl.lds
index 53f0cbd..a90404f 100644
--- a/arch/arm/cpu/armv7/sunxi/u-boot-spl.lds
+++ b/arch/arm/cpu/armv7/sunxi/u-boot-spl.lds
@@ -16,8 +16,6 @@
  */
 MEMORY { .sram : ORIGIN = CONFIG_SPL_TEXT_BASE,\
 		LENGTH = CONFIG_SPL_MAX_SIZE }
-MEMORY { .sdram : ORIGIN = CONFIG_SPL_BSS_START_ADDR, \
-		LENGTH = CONFIG_SPL_BSS_MAX_SIZE }
 
 OUTPUT_FORMAT("elf32-littlearm", "elf32-littlearm", "elf32-littlearm")
 OUTPUT_ARCH(arm)
@@ -54,5 +52,5 @@ SECTIONS
 		*(.bss*)
 		. = ALIGN(4);
 		__bss_end = .;
-	} > .sdram
+	} > .sram
 }
diff --git a/include/configs/sunxi-common.h b/include/configs/sunxi-common.h
index 94275a7..e3fe965 100644
--- a/include/configs/sunxi-common.h
+++ b/include/configs/sunxi-common.h
@@ -75,7 +75,6 @@
  * since it needs to fit in with the other values. By also #defining it
  * we get warnings if the Kconfig value mismatches. */
 #define CONFIG_SPL_STACK_R_ADDR		0x2fe00000
-#define CONFIG_SPL_BSS_START_ADDR	0x2ff80000
 #else
 #define SDRAM_OFFSET(x) 0x4##x
 #define CONFIG_SYS_SDRAM_BASE		0x40000000
@@ -86,11 +85,8 @@
  * since it needs to fit in with the other values. By also #defining it
  * we get warnings if the Kconfig value mismatches. */
 #define CONFIG_SPL_STACK_R_ADDR		0x4fe00000
-#define CONFIG_SPL_BSS_START_ADDR	0x4ff80000
 #endif
 
-#define CONFIG_SPL_BSS_MAX_SIZE		0x00080000 /* 512 KiB */
-
 #if defined(CONFIG_MACH_SUN9I) || defined(CONFIG_MACH_SUN50I)
 /*
  * The A80's A1 sram starts at 0x00010000 rather then at 0x00000000 and is
-- 
2.9.0



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