ref(linker): split lma and vma of data sec for non unified plats

The linker script sets the .data section’s LMA (load address) to
_data_lma_start, which is always after .rodata. For non-unified memory,
it moves the location counter to PLAT_DATA_MEM before defining .data, so
the VMA (virtual address at runtime) is in the data memory region, while
the section is still loaded from _data_lma_start. This logic ensures that
on platforms with split code/data memories, .data is loaded from one region
(LMA) but placed at a different runtime address (VMA). On unified memory,
both addresses are the same.

Signed-off-by: Daniel Oliveira <[email protected]>

Author: danielRep

src/linker.ld

@@ -30,9 +30,15 @@ SECTIONS
 		*(.rdata .rodata .rodata.*)
 	}
 
-    . = ALIGN(PAGE_SIZE); /* start RW sections in separate page */
-	
-	.data : {
+	. = ALIGN(PAGE_SIZE); /* start RW sections in separate page */
+	_data_lma_start = .;
+
+#ifdef MEM_NON_UNIFIED
+	. = PLAT_DATA_MEM;	/* Changed location counter to VMA address */
+	_data_vma_start = .;
+#endif
+
+	.data : AT (_data_lma_start){
 		*(.data .data.*)
         PROVIDE(__global_pointer$ = . + 0x800);
 		*(.sdata .sdata.* .sdata2.*)
@@ -51,15 +57,27 @@ SECTIONS
 
     . = ALIGN(PAGE_SIZE);
     _image_load_end = .;
+#ifdef MEM_NON_UNIFIED
+	/* Save the current location counter (VMA) and switch to LMA for .vm_images */
+	_vma_before_vm_images = .;
+    _image_load_end = _data_lma_start + (_image_load_end - _data_vma_start);
+	. = _image_load_end;
+#endif
 
 	/* Sections to be allocated only in physical memory, not in VA space */
 
-	.vm_images : SUBALIGN(PAGE_SIZE) {
-		_vm_image_start = .;
-		KEEP(*(.vm_image*))
-	}
+    .vm_images : AT(_image_load_end) SUBALIGN(PAGE_SIZE) {
+        _vm_image_start = .;
+        KEEP(*(.vm_image*))
+    }
+
+#ifdef MEM_NON_UNIFIED
+    /* Restore the location counter (VMA) */
+    . = _vma_before_vm_images;
+#endif
+
 	. = ALIGN(PAGE_SIZE);
-	_vm_image_end = .;
+	_vm_image_end = _vm_image_start + SIZEOF(.vm_images);
     _image_noload_start = .;
     extra_allocated_phys_mem = _image_noload_start - _image_load_end;