[kvm-unit-tests PATCH v3 13/18] arm64: Simplify efi_mem_init

[Andrew Jones <andrew.jones@linux.dev>]

Reduce the EFI mem_map loop to only setting flags and finding the
largest free memory region. Then, apply memregions_split() for
the code/data region split (which requires ensuring _etext is
page aligned). Finally, do the rest of the things that used to be
done in the EFI mem_map loop in a separate mem_region loop.

Reviewed-by: Nikos Nikoleris <nikos.nikoleris@arm.com>
Signed-off-by: Andrew Jones <andrew.jones@linux.dev>
---
 arm/efi/elf_aarch64_efi.lds |  1 +
 lib/arm/setup.c             | 45 +++++++++++++++++--------------------
 2 files changed, 21 insertions(+), 25 deletions(-)

diff --git a/arm/efi/elf_aarch64_efi.lds b/arm/efi/elf_aarch64_efi.lds
index 836d98255d88..7a4192b77900 100644
--- a/arm/efi/elf_aarch64_efi.lds
+++ b/arm/efi/elf_aarch64_efi.lds
@@ -13,6 +13,7 @@ SECTIONS
     *(.rodata*)
     . = ALIGN(16);
   }
+  . = ALIGN(4096);
   _etext = .;
   _text_size = . - _text;
   .dynamic  : { *(.dynamic) }
diff --git a/lib/arm/setup.c b/lib/arm/setup.c
index 7f2043907634..b8c88b5bf011 100644
--- a/lib/arm/setup.c
+++ b/lib/arm/setup.c
@@ -301,9 +301,7 @@ static efi_status_t efi_mem_init(efi_bootinfo_t *efi_bootinfo)
 	struct efi_boot_memmap *map = &(efi_bootinfo->mem_map);
 	efi_memory_desc_t *buffer = *map->map;
 	efi_memory_desc_t *d = NULL;
-	struct mem_region r;
-	uintptr_t text = (uintptr_t)&_text, etext = ALIGN((uintptr_t)&_etext, 4096);
-	uintptr_t data = (uintptr_t)&_data, edata = ALIGN((uintptr_t)&_edata, 4096);
+	struct mem_region r, *code, *data;
 	const void *fdt = efi_bootinfo->fdt;
 
 	/*
@@ -337,21 +335,7 @@ static efi_status_t efi_mem_init(efi_bootinfo_t *efi_bootinfo)
 			r.flags = MR_F_IO;
 			break;
 		case EFI_LOADER_CODE:
-			if (r.start <= text && r.end > text) {
-				/* This is the unit test region. Flag the code separately. */
-				phys_addr_t tmp = r.end;
-
-				assert(etext <= data);
-				assert(edata <= r.end);
-				r.flags = MR_F_CODE;
-				r.end = data;
-				memregions_add(&r);
-				r.start = data;
-				r.end = tmp;
-				r.flags = 0;
-			} else {
-				r.flags = MR_F_RESERVED;
-			}
+			r.flags = MR_F_CODE;
 			break;
 		case EFI_CONVENTIONAL_MEMORY:
 			if (free_mem_pages < d->num_pages) {
@@ -361,15 +345,27 @@ static efi_status_t efi_mem_init(efi_bootinfo_t *efi_bootinfo)
 			break;
 		}
 
-		if (!(r.flags & MR_F_IO)) {
-			if (r.start < __phys_offset)
-				__phys_offset = r.start;
-			if (r.end > __phys_end)
-				__phys_end = r.end;
-		}
 		memregions_add(&r);
 	}
 
+	memregions_split((unsigned long)&_etext, &code, &data);
+	assert(code && (code->flags & MR_F_CODE));
+	if (data)
+		data->flags &= ~MR_F_CODE;
+
+	for (struct mem_region *m = mem_regions; m->end; ++m) {
+		if (m != code && (m->flags & MR_F_CODE))
+			m->flags = MR_F_RESERVED;
+
+		if (!(m->flags & MR_F_IO)) {
+			if (m->start < __phys_offset)
+				__phys_offset = m->start;
+			if (m->end > __phys_end)
+				__phys_end = m->end;
+		}
+	}
+	__phys_end &= PHYS_MASK;
+
 	if (fdt) {
 		unsigned long old_start = free_mem_start;
 		void *freemem = (void *)free_mem_start;
@@ -380,7 +376,6 @@ static efi_status_t efi_mem_init(efi_bootinfo_t *efi_bootinfo)
 		free_mem_pages = (free_mem_start - old_start) >> EFI_PAGE_SHIFT;
 	}
 
-	__phys_end &= PHYS_MASK;
 	asm_mmu_disable();
 
 	if (free_mem_pages == 0)
-- 
2.44.0