Use VA start and end linker symbols instead of length (d0k3#865)

GerbilSoft · Jun 19, 2024 · 7b6b478 · 7b6b478
1 parent eee63dd
commit 7b6b478
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Showing 3 changed files with 12 additions and 10 deletions.
diff --git a/arm11/link.ld b/arm11/link.ld
@@ -16,7 +16,7 @@ SECTIONS
         __text_va = ABSOLUTE(.);
         *(.text*)
         . = ALIGN(4K);
-        __text_len = . - __text_va;
+        __text_va_end = .;
     } >AXIWRAM
 
     .data : ALIGN(4K)
@@ -25,7 +25,7 @@ SECTIONS
         __data_va = ABSOLUTE(.);
         *(.data*)
         . = ALIGN(4K);
-        __data_len = . - __data_va;
+        __data_va_end = .;
     } >AXIWRAM
 
     .rodata : ALIGN(4K)
@@ -34,7 +34,7 @@ SECTIONS
         __rodata_va = ABSOLUTE(.);
         *(.rodata*)
         . = ALIGN(4K);
-        __rodata_len = . - __rodata_va;
+        __rodata_va_end = .;
     } >AXIWRAM
 
     .shared (NOLOAD) : ALIGN(4K)
@@ -43,7 +43,7 @@ SECTIONS
         __shared_va = ABSOLUTE(.);
         *(.shared*)
         . = ALIGN(4K);
-        __shared_len = . - __shared_va;
+        __shared_va_end = .;
     } >AXIWRAM
 
     .bss (NOLOAD) : ALIGN(4K)
@@ -52,6 +52,6 @@ SECTIONS
         __bss_va = ABSOLUTE(.);
         *(.bss*)
         . = ALIGN(4K);
-        __bss_len = . - __bss_va;
+        __bss_va_end = .;
     } >AXIWRAM
 }
diff --git a/arm11/source/boot.s b/arm11/source/boot.s
@@ -76,10 +76,12 @@ __boot:
     b 1b
 
 corezero_start:
-    @ assume __bss_len is 128 byte aligned
+    @ assumes the .bss section size is 128 byte aligned (or zero)
     ldr r0, =__bss_pa
-    ldr r1, =__bss_len
-    add r1, r0, r1
+    ldr r1, =__bss_va_end   @ calculate the length of .bss using the VA start and end
+    ldr r2, =__bss_va
+    sub r1, r1, r2
+    add r1, r0, r1          @ fixup to be PA start and end
     mov r2, #0
     mov r3, #0
     mov r4, #0

diff --git a/arm11/source/system/sections.h b/arm11/source/system/sections.h
@@ -20,7 +20,7 @@
 
 #include <types.h>
 
-#define DEF_SECT_(n)	extern u32 __##n##_pa, __##n##_va, __##n##_len;
+#define DEF_SECT_(n)	extern u32 __##n##_pa, __##n##_va, __##n##_va_end;
 DEF_SECT_(text)
 DEF_SECT_(data)
 DEF_SECT_(rodata)
@@ -30,6 +30,6 @@ DEF_SECT_(shared)
 
 #define SECTION_VA(n)	((u32)&__##n##_va)
 #define SECTION_PA(n)	((u32)&__##n##_pa)
-#define SECTION_LEN(n)	((u32)&__##n##_len)
+#define SECTION_LEN(n)	(((u32)(&__##n##_va_end) - (u32)(&__##n##_va)))
 
 #define SECTION_TRI(n)	SECTION_VA(n), SECTION_PA(n), SECTION_LEN(n)