Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
diff --git a/arch/v850/kernel/head.S b/arch/v850/kernel/head.S
new file mode 100644
index 0000000..c490b93
--- /dev/null
+++ b/arch/v850/kernel/head.S
@@ -0,0 +1,128 @@
+/*
+ * arch/v850/kernel/head.S -- Lowest-level startup code
+ *
+ * Copyright (C) 2001,02,03 NEC Electronics Corporation
+ * Copyright (C) 2001,02,03 Miles Bader <miles@gnu.org>
+ *
+ * This file is subject to the terms and conditions of the GNU General
+ * Public License. See the file COPYING in the main directory of this
+ * archive for more details.
+ *
+ * Written by Miles Bader <miles@gnu.org>
+ */
+
+#include <asm/clinkage.h>
+#include <asm/current.h>
+#include <asm/entry.h>
+#include <asm/thread_info.h>
+#include <asm/irq.h>
+
+
+/* Make a slightly more convenient alias for C_SYMBOL_NAME. */
+#define CSYM C_SYMBOL_NAME
+
+
+ .text
+
+ // Define `mach_early_init' as a weak symbol
+ .global CSYM(mach_early_init)
+ .weak CSYM(mach_early_init)
+
+C_ENTRY(start):
+ // Make sure interrupts are turned off, just in case
+ di
+
+#ifdef CONFIG_RESET_GUARD
+ // See if we got here via an unexpected reset
+ ld.w RESET_GUARD, r19 // Check current value of reset guard
+ mov RESET_GUARD_ACTIVE, r20
+ cmp r19, r20
+ bne 1f // Guard was not active
+
+ // If we get here, the reset guard was active. Load up some
+ // interesting values as arguments, and jump to the handler.
+ st.w r0, RESET_GUARD // Allow further resets to succeed
+ mov lp, r6 // Arg 0: return address
+ ld.b KM, r7 // Arg 1: kernel mode
+ mov sp, r9 // Arg 3: stack pointer
+ ld.w KSP, r19 // maybe switch to kernel stack
+ cmp r7, r0 // see if already in kernel mode
+ cmov z, r19, sp, sp // and switch to kernel stack if not
+ GET_CURRENT_TASK(r8) // Arg 2: task pointer
+ jr CSYM(unexpected_reset)
+
+1: st.w r20, RESET_GUARD // Turn on reset guard
+#endif /* CONFIG_RESET_GUARD */
+
+ // Setup a temporary stack for doing pre-initialization function calls.
+ //
+ // We can't use the initial kernel stack, because (1) it may be
+ // located in memory we're not allowed to touch, and (2) since
+ // it's in the data segment, calling memcpy to initialize that
+ // area from ROM will overwrite memcpy's return address.
+ mov hilo(CSYM(_init_stack_end) - 4), sp
+
+ // See if there's a platform-specific early-initialization routine
+ // defined; it's a weak symbol, so it will have an address of zero if
+ // there's not.
+ mov hilo(CSYM(mach_early_init)), r6
+ cmp r6, r0
+ bz 3f
+
+ // There is one, so call it. If this function is written in C, it
+ // should be very careful -- the stack pointer is valid, but very
+ // little else is (e.g., bss is not zeroed yet, and initialized data
+ // hasn't been).
+ jarl 2f, lp // first figure out return address
+2: add 3f - ., lp
+ jmp [r6] // do call
+3:
+
+#ifdef CONFIG_ROM_KERNEL
+ // Copy the data area from ROM to RAM
+ mov hilo(CSYM(_rom_copy_dst_start)), r6
+ mov hilo(CSYM(_rom_copy_src_start)), r7
+ mov hilo(CSYM(_rom_copy_dst_end)), r8
+ sub r6, r8
+ jarl CSYM(memcpy), lp
+#endif
+
+ // Load the initial thread's stack, and current task pointer (in r16)
+ mov hilo(CSYM(init_thread_union)), r19
+ movea THREAD_SIZE, r19, sp
+ ld.w TI_TASK[r19], CURRENT_TASK
+
+#ifdef CONFIG_TIME_BOOTUP
+ /* This stuff must come after mach_early_init, because interrupts may
+ not work until after its been called. */
+ jarl CSYM(highres_timer_reset), lp
+ jarl CSYM(highres_timer_start), lp
+#endif
+
+ // Kernel stack pointer save location
+ st.w sp, KSP
+
+ // Assert that we're in `kernel mode'
+ mov 1, r19
+ st.w r19, KM
+
+#ifdef CONFIG_ZERO_BSS
+ // Zero bss area, since we can't rely upon any loader to do so
+ mov hilo(CSYM(_sbss)), r6
+ mov r0, r7
+ mov hilo(CSYM(_ebss)), r8
+ sub r6, r8
+ jarl CSYM(memset), lp
+#endif
+
+ // What happens if the main kernel function returns (it shouldn't)
+ mov hilo(CSYM(machine_halt)), lp
+
+ // Start the linux kernel. We use an indirect jump to get extra
+ // range, because on some platforms this initial startup code
+ // (and the associated platform-specific code in mach_early_init)
+ // are located far away from the main kernel, e.g. so that they
+ // can initialize RAM first and copy the kernel or something.
+ mov hilo(CSYM(start_kernel)), r12
+ jmp [r12]
+C_END(start)