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#ifndef __ARCH_ARM_ASM_H__

#define __ARCH_ARM_ASM_H__

/* Top nibble of the byte denotes irqs/fiqs disabled, ARM state */

#define ARM_MODE_MASK   0x1F

#define ARM_MODE_SVC    0x13

#define ARM_MODE_UND    0x1B

#define ARM_MODE_ABT    0x17

#define ARM_MODE_IRQ    0x12

#define ARM_MODE_FIQ    0x11

#define ARM_MODE_USR    0x10

#define ARM_MODE_SYS    0x1F

#define ARM_NOIRQ_SVC   0xD3

#define ARM_NOIRQ_UND   0xDB

#define ARM_NOIRQ_ABT   0xD7

#define ARM_NOIRQ_IRQ   0xD2

#define ARM_NOIRQ_FIQ   0xD1

#define ARM_NOIRQ_USR   0xD0

#define ARM_NOIRQ_SYS   0xDF

/* For enabling *clear* these bits */

#define ARM_IRQ_BIT     0x080

#define ARM_FIQ_BIT     0x040

#define ARM_A_BIT       0x100 /* Asynchronous abort */

/* Notes about ARM instructions:

 *

 * TST instruction:

 *

 * Essentially TST "AND"s two values and the result affects the Z (Zero bit)

 * in CPSR, which can be used for conditions. For example in:

 *

 *      TST r0, #VALUE

 *

 * If anding r0 and #VALUE results in a positive value (i.e. they have a

 * common bit set as 1) then Z bit is 0, which accounts for an NE (Not equal)

 * condition. Consequently, e.g. a BEQ instruction would be skipped and a BNE

 * would be executed.

 *

 * In the opposite case, r0 and #VALUE has no common bits, and anding them

 * results in 0. This means Z bit is 1, and any EQ instruction coming afterwards

 * would be executed.

 *

 * I have made this explanation here because I think the behaviour of the Z bit

 * is not very clear in TST. Normally Z bit is used for equivalence (e.g. CMP

 * instruction) but in TST case even if two values were equal the Z bit could

 * point to an NE or EQ condition depending on whether the values have non-zero

 * bits.

 */

#define dbg_stop_here()         __asm__ __volatile__ (  "bkpt   #0\n" :: )

#define BEGIN_PROC(name)                        \

    .global name;                               \

    .type   name,function;                      \

    .align;                                     \

name:

#define END_PROC(name)                          \

.fend_##name:                                   \

    .size   name,.fend_##name - name;

#endif /* __ARCH_ARM_ASM_H__ */