Changeset cfdeedc in mainline for kernel/arch/ppc32/src/exception.S

Timestamp:

2018-10-21T23:12:23Z (7 years ago)

Author:

Jiří Zárevúcky <zarevucky.jiri@…>

Branches:

lfn, master, serial, ticket/834-toolchain-update, topic/msim-upgrade, topic/simplify-dev-export

Children:

bf05c74

Parents:

d59718e

git-author:

Jiří Zárevúcky <zarevucky.jiri@…> (2018-10-21 22:53:48)

git-committer:

Jiří Zárevúcky <zarevucky.jiri@…> (2018-10-21 23:12:23)

Message:

Keep kernel in ELF format

By keeping kernel in an ELF file (instead of converting it to
a flat binary), we can use the information it contains, like
symbol table and debug info.

We can also later implement more advanced functionality, like
loading kernel at multiple discontiguous blocks, or loading
a position-independent kernel at a randomized address.

Currently the functionality is quite restricted, to keep changes
to a minimum. Code in boot/generic/src/kernel.c validates that
the kernel image was built with the same addresses as the boot
loader uses, giving an extra level of sanity checking compared
to a flat binary.

File:

• kernel/arch/ppc32/src/exception.S (modified) (18 diffs)

kernel/arch/ppc32/src/exception.S

@@ -126 +126 @@
 .endm
 
-.org 0x100
+// XXX: K_UNMAPPED_TEXT_START section starts at 0x100,
+// so all the following .org directives are relative to that.
+#define ABSOLUTE(x) ((x) - 0x100)
+
+.org ABSOLUTE(0x100)
 SYMBOL(exc_system_reset)
         CONTEXT_STORE
@@ -133 +137 @@
         b jump_to_kernel
 
-.org 0x200
+.org ABSOLUTE(0x200)
 SYMBOL(exc_machine_check)
         CONTEXT_STORE
@@ -140 +144 @@
         b jump_to_kernel
 
-.org 0x300
+.org ABSOLUTE(0x300)
 SYMBOL(exc_data_storage)
         CONTEXT_STORE
@@ -147 +151 @@
         b jump_to_kernel
 
-.org 0x400
+.org ABSOLUTE(0x400)
 SYMBOL(exc_instruction_storage)
         CONTEXT_STORE
@@ -154 +158 @@
         b jump_to_kernel
 
-.org 0x500
+.org ABSOLUTE(0x500)
 SYMBOL(exc_external)
         CONTEXT_STORE
@@ -161 +165 @@
         b jump_to_kernel
 
-.org 0x600
+.org ABSOLUTE(0x600)
 SYMBOL(exc_alignment)
         CONTEXT_STORE
@@ -168 +172 @@
         b jump_to_kernel
 
-.org 0x700
+.org ABSOLUTE(0x700)
 SYMBOL(exc_program)
         CONTEXT_STORE
@@ -175 +179 @@
         b jump_to_kernel
 
-.org 0x800
+.org ABSOLUTE(0x800)
 SYMBOL(exc_fp_unavailable)
         CONTEXT_STORE
@@ -182 +186 @@
         b jump_to_kernel
 
-.org 0x900
+.org ABSOLUTE(0x900)
 SYMBOL(exc_decrementer)
         CONTEXT_STORE
@@ -189 +193 @@
         b jump_to_kernel
 
-.org 0xa00
+.org ABSOLUTE(0xa00)
 SYMBOL(exc_reserved0)
         CONTEXT_STORE
@@ -196 +200 @@
         b jump_to_kernel
 
-.org 0xb00
+.org ABSOLUTE(0xb00)
 SYMBOL(exc_reserved1)
         CONTEXT_STORE
@@ -203 +207 @@
         b jump_to_kernel
 
-.org 0xc00
+.org ABSOLUTE(0xc00)
 SYMBOL(exc_syscall)
         CONTEXT_STORE
@@ -209 +213 @@
         b jump_to_kernel_syscall
 
-.org 0xd00
+.org ABSOLUTE(0xd00)
 SYMBOL(exc_trace)
         CONTEXT_STORE
@@ -216 +220 @@
         b jump_to_kernel
 
-.org 0x1000
+.org ABSOLUTE(0x1000)
 SYMBOL(exc_itlb_miss)
         CONTEXT_STORE
@@ -223 +227 @@
         b jump_to_kernel
 
-.org 0x1100
+.org ABSOLUTE(0x1100)
 SYMBOL(exc_dtlb_miss_load)
         CONTEXT_STORE
@@ -230 +234 @@
         b jump_to_kernel
 
-.org 0x1200
+.org ABSOLUTE(0x1200)
 SYMBOL(exc_dtlb_miss_store)
         CONTEXT_STORE
@@ -237 +241 @@
         b jump_to_kernel
 
-.org 0x4000
+.org ABSOLUTE(0x4000)
 jump_to_kernel:
         mfsrr1 r5
@@ -289 +293 @@
         addis sp, sp, 0x8000
         rfi
+
+/* Rest is for stack. */
+
+.org ABSOLUTE(0x8000)