arm-trusted-firmware/lib/cpus/aarch64/dsu_helpers.S

61 lines
1.4 KiB
ArmAsm

/*
* Copyright (c) 2018, ARM Limited and Contributors. All rights reserved.
*
* SPDX-License-Identifier: BSD-3-Clause
*/
#include <asm_macros.S>
#include <dsu_def.h>
#include <errata_report.h>
/*
* DSU erratum 936184
* Check the DSU variant, revision and configuration to determine if the
* erratum applies. This erratum was fixed in r2p0.
*
* This function is called from both assembly and C environment. So it
* follows AAPCS.
*
* Clobbers: x0-x3
*/
.globl check_errata_dsu_936184
.globl errata_dsu_936184_wa
func check_errata_dsu_936184
mov x2, #ERRATA_NOT_APPLIES
mov x3, #ERRATA_APPLIES
/* Erratum applies only if ACP interface is present in DSU */
mov x0, x2
mrs x1, CLUSTERCFR_EL1
ubfx x1, x1, #CLUSTERCFR_ACP_SHIFT, #1
cbz x1, 1f
/* If ACP is present, check if DSU is older than r2p0 */
mrs x1, CLUSTERIDR_EL1
/* DSU variant and revision bitfields in CLUSTERIDR are adjacent */
ubfx x0, x1, #CLUSTERIDR_REV_SHIFT,\
#(CLUSTERIDR_REV_BITS + CLUSTERIDR_VAR_BITS)
mov x1, #(0x2 << CLUSTERIDR_REV_BITS)
cmp x0, x1
csel x0, x2, x3, hs
1:
ret
endfunc check_errata_dsu_936184
func errata_dsu_936184_wa
mov x20, x30
bl check_errata_dsu_936184
cbz x0, 1f
/* If erratum applies, we set a mask to a DSU control register */
mrs x0, CLUSTERACTLR_EL1
ldr x1, =DSU_ERRATA_936184_MASK
orr x0, x0, x1
msr CLUSTERACTLR_EL1, x0
isb
1:
ret x20
endfunc errata_dsu_936184_wa