blob: 805136537e75898939d7a73219baf68ad21a33c2 [file] [log] [blame]
/* CMSE wrapper function used to save, clear and restore callee saved registers
for cmse_nonsecure_call's.
Copyright (C) 2016-2022 Free Software Foundation, Inc.
Contributed by ARM Ltd.
This file is free software; you can redistribute it and/or modify it
under the terms of the GNU General Public License as published by the
Free Software Foundation; either version 3, or (at your option) any
later version.
This file is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of
General Public License for more details.
Under Section 7 of GPL version 3, you are granted additional
permissions described in the GCC Runtime Library Exception, version
3.1, as published by the Free Software Foundation.
You should have received a copy of the GNU General Public License and
a copy of the GCC Runtime Library Exception along with this program;
see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
<>. */
.syntax unified
#ifdef __ARM_PCS_VFP
# if (__ARM_FP & 0x8) || (__ARM_FEATURE_MVE & 1)
.fpu fpv5-d16
# else
.fpu fpv4-sp-d16
# endif
.global __gnu_cmse_nonsecure_call
#if defined(__ARM_ARCH_8M_MAIN__)
push {r5-r11,lr}
mov r7, r4
mov r8, r4
mov r9, r4
mov r10, r4
mov r11, r4
mov ip, r4
/* Save and clear callee-saved registers only if we are dealing with hard float
ABI. The unused caller-saved registers have already been cleared by GCC
generated code. */
#ifdef __ARM_PCS_VFP
vpush.f64 {d8-d15}
mov r5, #0
vmov d8, r5, r5
#if __ARM_FP & 0x04
vmov s18, s19, r5, r5
vmov s20, s21, r5, r5
vmov s22, s23, r5, r5
vmov s24, s25, r5, r5
vmov s26, s27, r5, r5
vmov s28, s29, r5, r5
vmov s30, s31, r5, r5
#elif (__ARM_FP & 0x8) || (__ARM_FEATURE_MVE & 1)
vmov.f64 d9, d8
vmov.f64 d10, d8
vmov.f64 d11, d8
vmov.f64 d12, d8
vmov.f64 d13, d8
vmov.f64 d14, d8
vmov.f64 d15, d8
#error "Half precision implementation not supported."
/* Clear the cumulative exception-status bits (0-4,7) and the
condition code bits (28-31) of the FPSCR. */
vmrs r5, fpscr
movw r6, #65376
movt r6, #4095
ands r5, r6
vmsr fpscr, r5
/* We are not dealing with hard float ABI, so we can safely use the vlstm and
vlldm instructions without needing to preserve the registers used for
argument passing. */
sub sp, sp, #0x88 /* Reserve stack space to save all floating point
registers, including FPSCR. */
vlstm sp /* Lazy store and clearance of d0-d16 and FPSCR. */
#endif /* __ARM_PCS_VFP */
/* Make sure to clear the 'GE' bits of the APSR register if 32-bit SIMD
instructions are available. */
#if defined(__ARM_FEATURE_SIMD32)
msr APSR_nzcvqg, r4
msr APSR_nzcvq, r4
mov r5, r4
mov r6, r4
blxns r4
#ifdef __ARM_PCS_VFP
vpop.f64 {d8-d15}
/* VLLDM erratum mitigation sequence. */
mrs r5, control
tst r5, #8 /* CONTROL_S.SFPA */
it ne
.inst.w 0xeeb00a40 /* vmovne s0, s0 */
vlldm sp /* Lazy restore of d0-d16 and FPSCR. */
add sp, sp, #0x88 /* Free space used to save floating point registers. */
#endif /* __ARM_PCS_VFP */
pop {r5-r11, pc}
#elif defined (__ARM_ARCH_8M_BASE__)
push {r5-r7, lr}
mov r5, r8
mov r6, r9
mov r7, r10
push {r5-r7}
mov r5, r11
push {r5}
mov r5, r4
mov r6, r4
mov r7, r4
mov r8, r4
mov r9, r4
mov r10, r4
mov r11, r4
mov ip, r4
msr APSR_nzcvq, r4
blxns r4
pop {r5}
mov r11, r5
pop {r5-r7}
mov r10, r7
mov r9, r6
mov r8, r5
pop {r5-r7, pc}
#error "This should only be used for armv8-m base- and mainline."