[PATCH 4/4] xilinx: common: Change bootm_size variable setting

[Michal Simek]

Linux kernel for arm32 requires dtb and initrd to be placed in low memory
to work properly. This requirement is described in chapter 4b) and 5) in
Linux documentation (Documentation/arm/booting.rst).

There is an issue on arm32 with 2GB of memory that bootm_size is bigger
than Linux lowmem (for example with VMSPLIT_3G). That's why limit bootm
size on these systems not to be above 768MB.

Signed-off-by: Michal Simek <michal.simek at xilinx.com>
---

 board/xilinx/common/board.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/board/xilinx/common/board.c b/board/xilinx/common/board.c
index 581c88ad49a4..eab389d049f2 100644
--- a/board/xilinx/common/board.c
+++ b/board/xilinx/common/board.c
@@ -78,11 +78,15 @@ void *board_fdt_blob_setup(void)
 int board_late_init_xilinx(void)
 {
 	u32 ret = 0;
+	phys_size_t bootm_size = gd->ram_size;
+
+	if (CONFIG_IS_ENABLED(ARCH_ZYNQ))
+		bootm_size = min(bootm_size, (phys_size_t)(SZ_512M + SZ_256M));
 
 	ret |= env_set_hex("script_offset_f", CONFIG_BOOT_SCRIPT_OFFSET);
 
 	ret |= env_set_addr("bootm_low", (void *)gd->ram_base);
-	ret |= env_set_addr("bootm_size", (void *)gd->ram_size);
+	ret |= env_set_addr("bootm_size", (void *)bootm_size);
 
 	if (ret)
 		printf("%s: Saving run time variables FAILED\n", __func__);
-- 
2.28.0