SoC: sdm845: find and save KASLR to env variables
KASLR address is needed to boot fully functional Android.
KASLR is set by primary bootloader, and since u-boot is used
as a secondary bootloader(replacing kernel) on sdm845 platform,
KASLR may be found by comparing memory chunks at relocaddr over
supposed KASLR range.
Signed-off-by: Dzmitry Sankouski <dsankouski@gmail.com>
Reviewed-by: Ramon Fried <rfried.dev@gmail.com>
diff --git a/arch/arm/mach-snapdragon/init_sdm845.c b/arch/arm/mach-snapdragon/init_sdm845.c
index 5f53c21..1f88502 100644
--- a/arch/arm/mach-snapdragon/init_sdm845.c
+++ b/arch/arm/mach-snapdragon/init_sdm845.c
@@ -78,5 +78,23 @@
env_set("key_power", "0");
}
+ /*
+ * search for kaslr address, set by primary bootloader by searching first
+ * 0x100 relocated bytes at u-boot's initial load address range
+ */
+ uintptr_t start = gd->ram_base;
+ uintptr_t end = start + 0x800000;
+ u8 *addr = (u8 *)start;
+ phys_addr_t *relocaddr = (phys_addr_t *)gd->relocaddr;
+ u32 block_size = 0x1000;
+
+ while (memcmp(addr, relocaddr, 0x100) && (uintptr_t)addr < end)
+ addr += block_size;
+
+ if ((uintptr_t)addr >= end)
+ printf("KASLR not found in range 0x%lx - 0x%lx", start, end);
+ else
+ env_set_addr("KASLR", addr);
+
return 0;
}