Thumb-2: Implementation of the unified start-up and exceptions code
This patch implements the ARM/Thumb-2 unified kernel start-up and
exception handling code.
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
diff --git a/arch/arm/kernel/setup.c b/arch/arm/kernel/setup.c
index bc5e412..d4d4f77 100644
--- a/arch/arm/kernel/setup.c
+++ b/arch/arm/kernel/setup.c
@@ -25,6 +25,7 @@
#include <linux/smp.h>
#include <linux/fs.h>
+#include <asm/unified.h>
#include <asm/cpu.h>
#include <asm/cputype.h>
#include <asm/elf.h>
@@ -327,25 +328,38 @@
}
/*
+ * Define the placement constraint for the inline asm directive below.
+ * In Thumb-2, msr with an immediate value is not allowed.
+ */
+#ifdef CONFIG_THUMB2_KERNEL
+#define PLC "r"
+#else
+#define PLC "I"
+#endif
+
+ /*
* setup stacks for re-entrant exception handlers
*/
__asm__ (
"msr cpsr_c, %1\n\t"
- "add sp, %0, %2\n\t"
+ "add r14, %0, %2\n\t"
+ "mov sp, r14\n\t"
"msr cpsr_c, %3\n\t"
- "add sp, %0, %4\n\t"
+ "add r14, %0, %4\n\t"
+ "mov sp, r14\n\t"
"msr cpsr_c, %5\n\t"
- "add sp, %0, %6\n\t"
+ "add r14, %0, %6\n\t"
+ "mov sp, r14\n\t"
"msr cpsr_c, %7"
:
: "r" (stk),
- "I" (PSR_F_BIT | PSR_I_BIT | IRQ_MODE),
+ PLC (PSR_F_BIT | PSR_I_BIT | IRQ_MODE),
"I" (offsetof(struct stack, irq[0])),
- "I" (PSR_F_BIT | PSR_I_BIT | ABT_MODE),
+ PLC (PSR_F_BIT | PSR_I_BIT | ABT_MODE),
"I" (offsetof(struct stack, abt[0])),
- "I" (PSR_F_BIT | PSR_I_BIT | UND_MODE),
+ PLC (PSR_F_BIT | PSR_I_BIT | UND_MODE),
"I" (offsetof(struct stack, und[0])),
- "I" (PSR_F_BIT | PSR_I_BIT | SVC_MODE)
+ PLC (PSR_F_BIT | PSR_I_BIT | SVC_MODE)
: "r14");
}
