Have you enabled the NEON unit? It is disabled out of reset and hast to be enabled in your start-up code. Something like:; Enable Access to CP10 and CP11; --------------------------------; This is done by adjusting the contents of the CP15 Coproccesor Access Control Register (CACR) MRC p15, 0, r1, c1, c0, 2 ; Read CACR into r1 ORR r1, r1, #(0xf << 20) ; Enable full access for p10 & p11 MCR p15, 0, r1, c1, c0, 2 ; Write back into CACR MOV r1, #0 ISB ; Enable the VFP; ------------------- MOV r0, #0x40000000 VMSR FPEXC, r0
; Enable Access to CP10 and CP11; --------------------------------; This is done by adjusting the contents of the CP15 Coproccesor Access Control Register (CACR) MRC p15, 0, r1, c1, c0, 2 ; Read CACR into r1 ORR r1, r1, #(0xf << 20) ; Enable full access for p10 & p11 MCR p15, 0, r1, c1, c0, 2 ; Write back into CACR MOV r1, #0 ISB ; Enable the VFP; ------------------- MOV r0, #0x40000000 VMSR FPEXC, r0