51 lines
981 B
ArmAsm
51 lines
981 B
ArmAsm
/*
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** gint:core:vbr - Assembler-level VBR management
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*/
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.global _gint_setvbr
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.text
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.align 2
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/* gint_setvbr()
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Changes the VBR address and the calls the configuration function while
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interrupts are disabled. The configuration function must change either the
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priority registers or the interrupt masks, and make sure that all the
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interrupts that it leaves enabled are handled by the new VBR handlers.
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@arg vbr New VBR address (uint32_t)
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@arg configure Configuration function (void -> void)
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Returns the previous VBR address. */
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_gint_setvbr:
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mov.l r9, @-r15
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mov.l r8, @-r15
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sts.l pr, @-r15
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mov #1, r8
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mov #28, r0
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shld r0, r8
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/* Block all interrupts */
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stc sr, r0
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or r8, r0
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ldc r0, sr
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/* Set the new VBR address */
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stc vbr, r9
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ldc r4, vbr
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/* Call the configuration function */
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jsr @r5
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nop
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/* Enable interrupts again */
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stc sr, r0
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not r8, r8
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and r8, r0
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ldc r0, sr
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lds.l @r15+, pr
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mov.l @r15+, r8
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mov r9, r0
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rts
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mov.l @r15+, r9
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