1 /* 2 * Copyright (c) 2017-2022, Arm Limited and Contributors. All rights reserved. 3 * 4 * SPDX-License-Identifier: BSD-3-Clause 5 */ 6 7 #include <stdbool.h> 8 9 #include <arch.h> 10 #include <arch_features.h> 11 #include <arch_helpers.h> 12 #include <lib/el3_runtime/pubsub.h> 13 #include <lib/extensions/spe.h> 14 psb_csync(void)15static inline void psb_csync(void) 16 { 17 /* 18 * The assembler does not yet understand the psb csync mnemonic 19 * so use the equivalent hint instruction. 20 */ 21 __asm__ volatile("hint #17"); 22 } 23 spe_enable(bool el2_unused)24void spe_enable(bool el2_unused) 25 { 26 uint64_t v; 27 28 if (el2_unused) { 29 /* 30 * MDCR_EL2.TPMS (ARM v8.2): Do not trap statistical 31 * profiling controls to EL2. 32 * 33 * MDCR_EL2.E2PB (ARM v8.2): SPE enabled in Non-secure 34 * state. Accesses to profiling buffer controls at 35 * Non-secure EL1 are not trapped to EL2. 36 */ 37 v = read_mdcr_el2(); 38 v &= ~MDCR_EL2_TPMS; 39 v |= MDCR_EL2_E2PB(MDCR_EL2_E2PB_EL1); 40 write_mdcr_el2(v); 41 } 42 43 /* 44 * MDCR_EL2.NSPB (ARM v8.2): SPE enabled in Non-secure state 45 * and disabled in secure state. Accesses to SPE registers at 46 * S-EL1 generate trap exceptions to EL3. 47 * 48 * MDCR_EL3.EnPMSN (ARM v8.7): Do not trap access to PMSNEVFR_EL1 49 * register at NS-EL1 or NS-EL2 to EL3 if FEAT_SPEv1p2 is implemented. 50 * Setting this bit to 1 doesn't have any effect on it when 51 * FEAT_SPEv1p2 not implemented. 52 */ 53 v = read_mdcr_el3(); 54 v |= MDCR_NSPB(MDCR_NSPB_EL1) | MDCR_EnPMSN_BIT; 55 write_mdcr_el3(v); 56 } 57 spe_disable(void)58void spe_disable(void) 59 { 60 uint64_t v; 61 62 /* Drain buffered data */ 63 psb_csync(); 64 dsbnsh(); 65 66 /* Disable profiling buffer */ 67 v = read_pmblimitr_el1(); 68 v &= ~(1ULL << 0); 69 write_pmblimitr_el1(v); 70 isb(); 71 } 72 spe_drain_buffers_hook(const void * arg)73static void *spe_drain_buffers_hook(const void *arg) 74 { 75 if (!is_feat_spe_supported()) 76 return (void *)-1; 77 78 /* Drain buffered data */ 79 psb_csync(); 80 dsbnsh(); 81 82 return (void *)0; 83 } 84 85 SUBSCRIBE_TO_EVENT(cm_entering_secure_world, spe_drain_buffers_hook); 86
