35 lines
1.1 KiB
ArmAsm
35 lines
1.1 KiB
ArmAsm
#include "config.h"
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/* On native platform we protect ourself by disabling interrupts
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* then we check current processor mode. If we are called
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* from exception we need to save state and switch to SYS and
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* after obtaining SP we restore everything from saved state.
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*
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* On RaaA we are called in USER mode most probably and
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* cpsr mangling is restricted. We simply copy SP value
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* in this situation
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*/
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.section .text
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.type __get_sp,%function
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.global __get_sp
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__get_sp:
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#if (CONFIG_PLATFORM & PLATFORM_NATIVE)
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mrs r1, cpsr /* save current state */
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orr r0, r1, #0xc0
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msr cpsr_c, r0 /* disable IRQ and FIQ */
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and r0, r1, #0x1f /* get current mode */
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cmp r0, #0x1f /* are we in sys mode? */
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beq get_sp
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call_from_exception:
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mrs r0, spsr /* get saved state */
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and r0, r0, #0x1f /* get mode bits */
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orr r0, r0, #0xc0 /* no FIQ no IRQ */
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msr cpsr_c, r0 /* change mode */
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get_sp:
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#endif
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mov r0, sp /* get SP */
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#if (CONFIG_PLATFORM & PLATFORM_NATIVE)
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msr cpsr_c, r1 /* restore mode */
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#endif
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bx lr
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.size __get_sp, . - __get_sp
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