ZynqMP: revert WOLFBOOT_ORIGIN to 0x8000000

The previous commit moved WOLFBOOT_ORIGIN from 0x8000000 to 0x10000000
to match the linker script, but WOLFBOOT_LOAD_ADDRESS is also 0x10000000.
This causes wolfBoot to overwrite itself when loading the firmware image
(32MB FIT written to 0x10000000 overwrites wolfBoot's .text at the same
address mid-read, hanging the boot).

Revert to 0x8000000 (128MB, same as U-Boot) and update linker script to
match. WOLFBOOT_LOAD_ADDRESS at 0x10000000 is safely above wolfBoot's
2MB footprint at 0x8000000-0x8200000.

Author: dgarske

config/examples/zynqmp_sdcard.config

@@ -103,8 +103,10 @@ CFLAGS_EXTRA+=-DLINUX_BOOTARGS_ROOT=\"/dev/mmcblk0p4\"
 # ============================================================================
 # Boot Memory Layout
 # ============================================================================
-# wolfBoot runs from DDR at 0x10000000 (loaded by BL31; see hal/zynq.ld).
-WOLFBOOT_ORIGIN=0x10000000
+# wolfBoot runs from DDR at 0x8000000 (128MB, same as U-Boot, loaded via BL31).
+# Must match the ORIGIN in hal/zynq.ld. WOLFBOOT_LOAD_ADDRESS must be above
+# this region (wolfBoot is ~2MB) to avoid self-overwrite during firmware load.
+WOLFBOOT_ORIGIN=0x8000000
 
 # Load Partition to RAM Address (Linux kernel loads here)
 WOLFBOOT_LOAD_ADDRESS?=0x10000000

hal/zynq.ld

@@ -13,21 +13,12 @@ MEMORY
 {
    /* psu_ddr_0_MEM_0 : ORIGIN = 0x0, LENGTH = 0x80000000 */
    /* wolfBoot DDR location (2MB reserved):
-    *   Loaded by FSBL/BL31 to DDR at 0x10000000 (256MB). Must be above
-    *   the OS kernel load region: for FIT images whose "load" address is
-    *   0x00200000 (typical for AArch64 kernels) and whose payload
-    *   approaches or exceeds ~126MB, the kernel memcpy into 0x00200000..
-    *   sweeps across 0x08000000 and would clobber wolfBoot if linked
-    *   there. Same address used for QSPI and SD card boot.
-    *
-    *   WOLFBOOT_LOAD_ADDRESS (signed-image staging base) also defaults to
-    *   0x10000000 on the SD-card config. The overlap with wolfBoot's own
-    *   2MB text region is safe because wolfBoot completes the verify and
-    *   jump sequence from I-cache; the I-cache is only invalidated inside
-    *   el2_flush_and_disable_mmu, immediately before control transfers to
-    *   the loaded kernel (which no longer needs wolfBoot's .text).
+    *   Loaded by FSBL/BL31 to DDR at 0x8000000 (128MB, same as U-Boot).
+    *   WOLFBOOT_LOAD_ADDRESS (signed-image staging area) must be above
+    *   this region to avoid overwriting wolfBoot during firmware load.
+    *   Must match WOLFBOOT_ORIGIN in the target .config.
     */
-   psu_ddr_0_MEM_0 : ORIGIN = 0x10000000, LENGTH = 0x200000
+   psu_ddr_0_MEM_0 : ORIGIN = 0x8000000, LENGTH = 0x200000
    psu_ddr_1_MEM_0 : ORIGIN = 0x800000000, LENGTH = 0x80000000
    psu_ocm_ram_0_MEM_0 : ORIGIN = 0xFFFC0000, LENGTH = 0x40000
    psu_qspi_linear_0_MEM_0 : ORIGIN = 0xC0000000, LENGTH = 0x20000000