1/* 2 * Copyright (C) 2012 - Virtual Open Systems and Columbia University 3 * Author: Christoffer Dall <c.dall@virtualopensystems.com> 4 * 5 * This program is free software; you can redistribute it and/or modify 6 * it under the terms of the GNU General Public License version 2 as 7 * published by the Free Software Foundation. 8 * 9 * This program is distributed in the hope that it will be useful, 10 * but WITHOUT ANY WARRANTY; without even the implied warranty of 11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 12 * GNU General Public License for more details. 13 * 14 * You should have received a copy of the GNU General Public License 15 * along with this program. If not, see <http://www.gnu.org/licenses/>. 16 */ 17 18#include <linux/linkage.h> 19#include <asm/vfpmacros.h> 20 21 .text 22 .pushsection .hyp.text, "ax" 23 24/* void __vfp_save_state(struct vfp_hard_struct *vfp); */ 25ENTRY(__vfp_save_state) 26 push {r4, r5} 27 VFPFMRX r1, FPEXC 28 29 @ Make sure *really* VFP is enabled so we can touch the registers. 30 orr r5, r1, #FPEXC_EN 31 tst r5, #FPEXC_EX @ Check for VFP Subarchitecture 32 bic r5, r5, #FPEXC_EX @ FPEXC_EX disable 33 VFPFMXR FPEXC, r5 34 isb 35 36 VFPFMRX r2, FPSCR 37 beq 1f 38 39 @ If FPEXC_EX is 0, then FPINST/FPINST2 reads are upredictable, so 40 @ we only need to save them if FPEXC_EX is set. 41 VFPFMRX r3, FPINST 42 tst r5, #FPEXC_FP2V 43 VFPFMRX r4, FPINST2, ne @ vmrsne 441: 45 VFPFSTMIA r0, r5 @ Save VFP registers 46 stm r0, {r1-r4} @ Save FPEXC, FPSCR, FPINST, FPINST2 47 pop {r4, r5} 48 bx lr 49ENDPROC(__vfp_save_state) 50 51/* void __vfp_restore_state(struct vfp_hard_struct *vfp); 52 * Assume FPEXC_EN is on and FPEXC_EX is off */ 53ENTRY(__vfp_restore_state) 54 VFPFLDMIA r0, r1 @ Load VFP registers 55 ldm r0, {r0-r3} @ Load FPEXC, FPSCR, FPINST, FPINST2 56 57 VFPFMXR FPSCR, r1 58 tst r0, #FPEXC_EX @ Check for VFP Subarchitecture 59 beq 1f 60 VFPFMXR FPINST, r2 61 tst r0, #FPEXC_FP2V 62 VFPFMXR FPINST2, r3, ne 631: 64 VFPFMXR FPEXC, r0 @ FPEXC (last, in case !EN) 65 bx lr 66ENDPROC(__vfp_restore_state) 67 68 .popsection 69