[ARM] nommu: start-up code
This patch adds nommu version start-up code head-nommu.S.
The common part of the start-up codes is moved to head-common.S.
Signed-off-by: Hyok S. Choi <hyok.choi@samsung.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
diff --git a/arch/arm/kernel/head-nommu.S b/arch/arm/kernel/head-nommu.S
new file mode 100644
index 0000000..b093ab8
--- /dev/null
+++ b/arch/arm/kernel/head-nommu.S
@@ -0,0 +1,83 @@
+/*
+ * linux/arch/arm/kernel/head-nommu.S
+ *
+ * Copyright (C) 1994-2002 Russell King
+ * Copyright (C) 2003-2006 Hyok S. Choi
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * Common kernel startup code (non-paged MM)
+ * for 32-bit CPUs which has a process ID register(CP15).
+ *
+ */
+#include <linux/config.h>
+#include <linux/linkage.h>
+#include <linux/init.h>
+
+#include <asm/assembler.h>
+#include <asm/mach-types.h>
+#include <asm/procinfo.h>
+#include <asm/ptrace.h>
+#include <asm/constants.h>
+#include <asm/system.h>
+
+#define PROCINFO_INITFUNC 12
+
+/*
+ * Kernel startup entry point.
+ * ---------------------------
+ *
+ * This is normally called from the decompressor code. The requirements
+ * are: MMU = off, D-cache = off, I-cache = dont care, r0 = 0,
+ * r1 = machine nr.
+ *
+ * See linux/arch/arm/tools/mach-types for the complete list of machine
+ * numbers for r1.
+ *
+ */
+ __INIT
+ .type stext, %function
+ENTRY(stext)
+ msr cpsr_c, #PSR_F_BIT | PSR_I_BIT | MODE_SVC @ ensure svc mode
+ @ and irqs disabled
+ mrc p15, 0, r9, c0, c0 @ get processor id
+ bl __lookup_processor_type @ r5=procinfo r9=cpuid
+ movs r10, r5 @ invalid processor (r5=0)?
+ beq __error_p @ yes, error 'p'
+ bl __lookup_machine_type @ r5=machinfo
+ movs r8, r5 @ invalid machine (r5=0)?
+ beq __error_a @ yes, error 'a'
+
+ ldr r13, __switch_data @ address to jump to after
+ @ the initialization is done
+ adr lr, __after_proc_init @ return (PIC) address
+ add pc, r10, #PROCINFO_INITFUNC
+
+/*
+ * Set the Control Register and Read the process ID.
+ */
+ .type __after_proc_init, %function
+__after_proc_init:
+ mrc p15, 0, r0, c1, c0, 0 @ read control reg
+#ifdef CONFIG_ALIGNMENT_TRAP
+ orr r0, r0, #CR_A
+#else
+ bic r0, r0, #CR_A
+#endif
+#ifdef CONFIG_CPU_DCACHE_DISABLE
+ bic r0, r0, #CR_C
+#endif
+#ifdef CONFIG_CPU_BPREDICT_DISABLE
+ bic r0, r0, #CR_Z
+#endif
+#ifdef CONFIG_CPU_ICACHE_DISABLE
+ bic r0, r0, #CR_I
+#endif
+ mcr p15, 0, r0, c1, c0, 0 @ write control reg
+
+ mov pc, r13 @ clear the BSS and jump
+ @ to start_kernel
+
+#include "head-common.S"
