/***********************license start*************** * Author: Cavium Networks * * Contact: support@caviumnetworks.com * This file is part of the OCTEON SDK * * Copyright (c) 2003-2008 Cavium Networks * * This file is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License, Version 2, as * published by the Free Software Foundation. * * This file is distributed in the hope that it will be useful, but * AS-IS and WITHOUT ANY WARRANTY; without even the implied warranty * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE, TITLE, or * NONINFRINGEMENT. See the GNU General Public License for more * details. * * You should have received a copy of the GNU General Public License * along with this file; if not, write to the Free Software * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA * or visit http://www.gnu.org/licenses/. * * This file may also be available under a different license from Cavium. * Contact Cavium Networks for more information ***********************license end**************************************/ /* * Implementation of the Level 2 Cache (L2C) control, measurement, and * debugging facilities. */ #include #include #include /* * This spinlock is used internally to ensure that only one core is * performing certain L2 operations at a time. * * NOTE: This only protects calls from within a single application - * if multiple applications or operating systems are running, then it * is up to the user program to coordinate between them. */ static cvmx_spinlock_t cvmx_l2c_spinlock; static inline int l2_size_half(void) { uint64_t val = cvmx_read_csr(CVMX_L2D_FUS3); return !!(val & (1ull << 34)); } int cvmx_l2c_get_core_way_partition(uint32_t core) { uint32_t field; /* Validate the core number */ if (core >= cvmx_octeon_num_cores()) return -1; /* * Use the lower two bits of the coreNumber to determine the * bit offset of the UMSK[] field in the L2C_SPAR register. */ field = (core & 0x3) * 8; /* * Return the UMSK[] field from the appropriate L2C_SPAR * register based on the coreNumber. */ switch (core & 0xC) { case 0x0: return (cvmx_read_csr(CVMX_L2C_SPAR0) & (0xFF << field)) >> field; case 0x4: return (cvmx_read_csr(CVMX_L2C_SPAR1) & (0xFF << field)) >> field; case 0x8: return (cvmx_read_csr(CVMX_L2C_SPAR2) & (0xFF << field)) >> field; case 0xC: return (cvmx_read_csr(CVMX_L2C_SPAR3) & (0xFF << field)) >> field; } return 0; } int cvmx_l2c_set_core_way_partition(uint32_t core, uint32_t mask) { uint32_t field; uint32_t valid_mask; valid_mask = (0x1 << cvmx_l2c_get_num_assoc()) - 1; mask &= valid_mask; /* A UMSK setting which blocks all L2C Ways is an error. */ if (mask == valid_mask) return -1; /* Validate the core number */ if (core >= cvmx_octeon_num_cores()) return -1; /* Check to make sure current mask & new mask don't block all ways */ if (((mask | cvmx_l2c_get_core_way_partition(core)) & valid_mask) == valid_mask) return -1; /* Use the lower two bits of core to determine the bit offset of the * UMSK[] field in the L2C_SPAR register. */ field = (core & 0x3) * 8; /* Assign the new mask setting to the UMSK[] field in the appropriate * L2C_SPAR register based on the core_num. * */ switch (core & 0xC) { case 0x0: cvmx_write_csr(CVMX_L2C_SPAR0, (cvmx_read_csr(CVMX_L2C_SPAR0) & ~(0xFF << field)) | mask << field); break; case 0x4: cvmx_write_csr(CVMX_L2C_SPAR1, (cvmx_read_csr(CVMX_L2C_SPAR1) & ~(0xFF << field)) | mask << field); break; case 0x8: cvmx_write_csr(CVMX_L2C_SPAR2, (cvmx_read_csr(CVMX_L2C_SPAR2) & ~(0xFF << field)) | mask << field); break; case 0xC: cvmx_write_csr(CVMX_L2C_SPAR3, (cvmx_read_csr(CVMX_L2C_SPAR3) & ~(0xFF << field)) | mask << field); break; } return 0; } int cvmx_l2c_set_hw_way_partition(uint32_t mask) { uint32_t valid_mask; valid_mask = 0xff; if (OCTEON_IS_MODEL(OCTEON_CN58XX) || OCTEON_IS_MODEL(OCTEON_CN38XX)) { if (l2_size_half()) valid_mask = 0xf; } else if (l2_size_half()) valid_mask = 0x3; mask &= valid_mask; /* A UMSK setting which blocks all L2C Ways is an error. */ if (mask == valid_mask) return -1; /* Check to make sure current mask & new mask don't block all ways */ if (((mask | cvmx_l2c_get_hw_way_partition()) & valid_mask) == valid_mask) return -1; cvmx_write_csr(CVMX_L2C_SPAR4, (cvmx_read_csr(CVMX_L2C_SPAR4) & ~0xFF) | mask); return 0; } int cvmx_l2c_get_hw_way_partition(void) { return cvmx_read_csr(CVMX_L2C_SPAR4) & (0xFF); } void cvmx_l2c_config_perf(uint32_t counter, enum cvmx_l2c_event event, uint32_t clear_on_read) { union cvmx_l2c_pfctl pfctl; pfctl.u64 = cvmx_read_csr(CVMX_L2C_PFCTL); switch (counter) { case 0: pfctl.s.cnt0sel = event; pfctl.s.cnt0ena = 1; if (!cvmx_octeon_is_pass1()) pfctl.s.cnt0rdclr = clear_on_read; break; case 1: pfctl.s.cnt1sel = event; pfctl.s.cnt1ena = 1; if (!cvmx_octeon_is_pass1()) pfctl.s.cnt1rdclr = clear_on_read; break; case 2: pfctl.s.cnt2sel = event; pfctl.s.cnt2ena = 1; if (!cvmx_octeon_is_pass1()) pfctl.s.cnt2rdclr = clear_on_read; break; case 3: default: pfctl.s.cnt3sel = event; pfctl.s.cnt3ena = 1; if (!cvmx_octeon_is_pass1()) pfctl.s.cnt3rdclr = clear_on_read; break; } cvmx_write_csr(CVMX_L2C_PFCTL, pfctl.u64); } uint64_t cvmx_l2c_read_perf(uint32_t counter) { switch (counter) { case 0: return cvmx_read_csr(CVMX_L2C_PFC0); case 1: return cvmx_read_csr(CVMX_L2C_PFC1); case 2: return cvmx_read_csr(CVMX_L2C_PFC2); case 3: default: return cvmx_read_csr(CVMX_L2C_PFC3); } } /** * @INTERNAL * Helper function use to fault in cache lines for L2 cache locking * * @addr: Address of base of memory region to read into L2 cache * @len: Length (in bytes) of region to fault in */ static void fault_in(uint64_t addr, int len) { volatile char *ptr; volatile char dummy; /* * Adjust addr and length so we get all cache lines even for * small ranges spanning two cache lines */ len += addr & CVMX_CACHE_LINE_MASK; addr &= ~CVMX_CACHE_LINE_MASK; ptr = (volatile char *)cvmx_phys_to_ptr(addr); /* * Invalidate L1 cache to make sure all loads result in data * being in L2. */ CVMX_DCACHE_INVALIDATE; while (len > 0) { dummy += *ptr; len -= CVMX_CACHE_LINE_SIZE; ptr += CVMX_CACHE_LINE_SIZE; } } int cvmx_l2c_lock_line(uint64_t addr) { int retval = 0; union cvmx_l2c_dbg l2cdbg; union cvmx_l2c_lckbase lckbase; union cvmx_l2c_lckoff lckoff; union cvmx_l2t_err l2t_err; l2cdbg.u64 = 0; lckbase.u64 = 0; lckoff.u64 = 0; cvmx_spinlock_lock(&cvmx_l2c_spinlock); /* Clear l2t error bits if set */ l2t_err.u64 = cvmx_read_csr(CVMX_L2T_ERR); l2t_err.s.lckerr = 1; l2t_err.s.lckerr2 = 1; cvmx_write_csr(CVMX_L2T_ERR, l2t_err.u64); addr &= ~CVMX_CACHE_LINE_MASK; /* Set this core as debug core */ l2cdbg.s.ppnum = cvmx_get_core_num(); CVMX_SYNC; cvmx_write_csr(CVMX_L2C_DBG, l2cdbg.u64); cvmx_read_csr(CVMX_L2C_DBG); lckoff.s.lck_offset = 0; /* Only lock 1 line at a time */ cvmx_write_csr(CVMX_L2C_LCKOFF, lckoff.u64); cvmx_read_csr(CVMX_L2C_LCKOFF); if (((union cvmx_l2c_cfg) (cvmx_read_csr(CVMX_L2C_CFG))).s.idxalias) { int alias_shift = CVMX_L2C_IDX_ADDR_SHIFT + 2 * CVMX_L2_SET_BITS - 1; uint64_t addr_tmp = addr ^ (addr & ((1 << alias_shift) - 1)) >> CVMX_L2_SET_BITS; lckbase.s.lck_base = addr_tmp >> 7; } else { lckbase.s.lck_base = addr >> 7; } lckbase.s.lck_ena = 1; cvmx_write_csr(CVMX_L2C_LCKBASE, lckbase.u64); cvmx_read_csr(CVMX_L2C_LCKBASE); /* Make sure it gets there */ fault_in(addr, CVMX_CACHE_LINE_SIZE); lckbase.s.lck_ena = 0; cvmx_write_csr(CVMX_L2C_LCKBASE, lckbase.u64); cvmx_read_csr(CVMX_L2C_LCKBASE); /* Make sure it gets there */ /* Stop being debug core */ cvmx_write_csr(CVMX_L2C_DBG, 0); cvmx_read_csr(CVMX_L2C_DBG); l2t_err.u64 = cvmx_read_csr(CVMX_L2T_ERR); if (l2t_err.s.lckerr || l2t_err.s.lckerr2) retval = 1; /* We were unable to lock the line */ cvmx_spinlock_unlock(&cvmx_l2c_spinlock); return retval; } int cvmx_l2c_lock_mem_region(uint64_t start, uint64_t len) { int retval = 0; /* Round start/end to cache line boundaries */ len += start & CVMX_CACHE_LINE_MASK; start &= ~CVMX_CACHE_LINE_MASK; len = (len + CVMX_CACHE_LINE_MASK) & ~CVMX_CACHE_LINE_MASK; while (len) { retval += cvmx_l2c_lock_line(start); start += CVMX_CACHE_LINE_SIZE; len -= CVMX_CACHE_LINE_SIZE; } return retval; } void cvmx_l2c_flush(void) { uint64_t assoc, set; uint64_t n_assoc, n_set; union cvmx_l2c_dbg l2cdbg; cvmx_spinlock_lock(&cvmx_l2c_spinlock); l2cdbg.u64 = 0; if (!OCTEON_IS_MODEL(OCTEON_CN30XX)) l2cdbg.s.ppnum = cvmx_get_core_num(); l2cdbg.s.finv = 1; n_set = CVMX_L2_SETS; n_assoc = l2_size_half() ? (CVMX_L2_ASSOC / 2) : CVMX_L2_ASSOC; for (set = 0; set < n_set; set++) { for (assoc = 0; assoc < n_assoc; assoc++) { l2cdbg.s.set = assoc; /* Enter debug mode, and make sure all other ** writes complete before we enter debug ** mode */ CVMX_SYNCW; cvmx_write_csr(CVMX_L2C_DBG, l2cdbg.u64); cvmx_read_csr(CVMX_L2C_DBG); CVMX_PREPARE_FOR_STORE(CVMX_ADD_SEG (CVMX_MIPS_SPACE_XKPHYS, set * CVMX_CACHE_LINE_SIZE), 0); CVMX_SYNCW; /* Push STF out to L2 */ /* Exit debug mode */ CVMX_SYNC; cvmx_write_csr(CVMX_L2C_DBG, 0); cvmx_read_csr(CVMX_L2C_DBG); } } cvmx_spinlock_unlock(&cvmx_l2c_spinlock); } int cvmx_l2c_unlock_line(uint64_t address) { int assoc; union cvmx_l2c_tag tag; union cvmx_l2c_dbg l2cdbg; uint32_t tag_addr; uint32_t index = cvmx_l2c_address_to_index(address); cvmx_spinlock_lock(&cvmx_l2c_spinlock); /* Compute portion of address that is stored in tag */ tag_addr = ((address >> CVMX_L2C_TAG_ADDR_ALIAS_SHIFT) & ((1 << CVMX_L2C_TAG_ADDR_ALIAS_SHIFT) - 1)); for (assoc = 0; assoc < CVMX_L2_ASSOC; assoc++) { tag = cvmx_get_l2c_tag(assoc, index); if (tag.s.V && (tag.s.addr == tag_addr)) { l2cdbg.u64 = 0; l2cdbg.s.ppnum = cvmx_get_core_num(); l2cdbg.s.set = assoc; l2cdbg.s.finv = 1; CVMX_SYNC; /* Enter debug mode */ cvmx_write_csr(CVMX_L2C_DBG, l2cdbg.u64); cvmx_read_csr(CVMX_L2C_DBG); CVMX_PREPARE_FOR_STORE(CVMX_ADD_SEG (CVMX_MIPS_SPACE_XKPHYS, address), 0); CVMX_SYNC; /* Exit debug mode */ cvmx_write_csr(CVMX_L2C_DBG, 0); cvmx_read_csr(CVMX_L2C_DBG); cvmx_spinlock_unlock(&cvmx_l2c_spinlock); return tag.s.L; } } cvmx_spinlock_unlock(&cvmx_l2c_spinlock); return 0; } int cvmx_l2c_unlock_mem_region(uint64_t start, uint64_t len) { int num_unlocked = 0; /* Round start/end to cache line boundaries */ len += start & CVMX_CACHE_LINE_MASK; start &= ~CVMX_CACHE_LINE_MASK; len = (len + CVMX_CACHE_LINE_MASK) & ~CVMX_CACHE_LINE_MASK; while (len > 0) { num_unlocked += cvmx_l2c_unlock_line(start); start += CVMX_CACHE_LINE_SIZE; len -= CVMX_CACHE_LINE_SIZE; } return num_unlocked; } /* * Internal l2c tag types. These are converted to a generic structure * that can be used on all chips. */ union __cvmx_l2c_tag { uint64_t u64; struct cvmx_l2c_tag_cn50xx { uint64_t reserved:40; uint64_t V:1; /* Line valid */ uint64_t D:1; /* Line dirty */ uint64_t L:1; /* Line locked */ uint64_t U:1; /* Use, LRU eviction */ uint64_t addr:20; /* Phys mem addr (33..14) */ } cn50xx; struct cvmx_l2c_tag_cn30xx { uint64_t reserved:41; uint64_t V:1; /* Line valid */ uint64_t D:1; /* Line dirty */ uint64_t L:1; /* Line locked */ uint64_t U:1; /* Use, LRU eviction */ uint64_t addr:19; /* Phys mem addr (33..15) */ } cn30xx; struct cvmx_l2c_tag_cn31xx { uint64_t reserved:42; uint64_t V:1; /* Line valid */ uint64_t D:1; /* Line dirty */ uint64_t L:1; /* Line locked */ uint64_t U:1; /* Use, LRU eviction */ uint64_t addr:18; /* Phys mem addr (33..16) */ } cn31xx; struct cvmx_l2c_tag_cn38xx { uint64_t reserved:43; uint64_t V:1; /* Line valid */ uint64_t D:1; /* Line dirty */ uint64_t L:1; /* Line locked */ uint64_t U:1; /* Use, LRU eviction */ uint64_t addr:17; /* Phys mem addr (33..17) */ } cn38xx; struct cvmx_l2c_tag_cn58xx { uint64_t reserved:44; uint64_t V:1; /* Line valid */ uint64_t D:1; /* Line dirty */ uint64_t L:1; /* Line locked */ uint64_t U:1; /* Use, LRU eviction */ uint64_t addr:16; /* Phys mem addr (33..18) */ } cn58xx; struct cvmx_l2c_tag_cn58xx cn56xx; /* 2048 sets */ struct cvmx_l2c_tag_cn31xx cn52xx; /* 512 sets */ }; /** * @INTERNAL * Function to read a L2C tag. This code make the current core * the 'debug core' for the L2. This code must only be executed by * 1 core at a time. * * @assoc: Association (way) of the tag to dump * @index: Index of the cacheline * * Returns The Octeon model specific tag structure. This is * translated by a wrapper function to a generic form that is * easier for applications to use. */ static union __cvmx_l2c_tag __read_l2_tag(uint64_t assoc, uint64_t index) { uint64_t debug_tag_addr = (((1ULL << 63) | (index << 7)) + 96); uint64_t core = cvmx_get_core_num(); union __cvmx_l2c_tag tag_val; uint64_t dbg_addr = CVMX_L2C_DBG; unsigned long flags; union cvmx_l2c_dbg debug_val; debug_val.u64 = 0; /* * For low core count parts, the core number is always small enough * to stay in the correct field and not set any reserved bits. */ debug_val.s.ppnum = core; debug_val.s.l2t = 1; debug_val.s.set = assoc; /* * Make sure core is quiet (no prefetches, etc.) before * entering debug mode. */ CVMX_SYNC; /* Flush L1 to make sure debug load misses L1 */ CVMX_DCACHE_INVALIDATE; local_irq_save(flags); /* * The following must be done in assembly as when in debug * mode all data loads from L2 return special debug data, not * normal memory contents. Also, interrupts must be * disabled, since if an interrupt occurs while in debug mode * the ISR will get debug data from all its memory reads * instead of the contents of memory */ asm volatile (".set push \n" " .set mips64 \n" " .set noreorder \n" /* Enter debug mode, wait for store */ " sd %[dbg_val], 0(%[dbg_addr]) \n" " ld $0, 0(%[dbg_addr]) \n" /* Read L2C tag data */ " ld %[tag_val], 0(%[tag_addr]) \n" /* Exit debug mode, wait for store */ " sd $0, 0(%[dbg_addr]) \n" " ld $0, 0(%[dbg_addr]) \n" /* Invalidate dcache to discard debug data */ " cache 9, 0($0) \n" " .set pop" : [tag_val] "=r"(tag_val.u64) : [dbg_addr] "r"(dbg_addr), [dbg_val] "r"(debug_val.u64), [tag_addr] "r"(debug_tag_addr) : "memory"); local_irq_restore(flags); return tag_val; } union cvmx_l2c_tag cvmx_l2c_get_tag(uint32_t association, uint32_t index) { union __cvmx_l2c_tag tmp_tag; union cvmx_l2c_tag tag; tag.u64 = 0; if ((int)association >= cvmx_l2c_get_num_assoc()) { cvmx_dprintf ("ERROR: cvmx_get_l2c_tag association out of range\n"); return tag; } if ((int)index >= cvmx_l2c_get_num_sets()) { cvmx_dprintf("ERROR: cvmx_get_l2c_tag " "index out of range (arg: %d, max: %d\n", index, cvmx_l2c_get_num_sets()); return tag; } /* __read_l2_tag is intended for internal use only */ tmp_tag = __read_l2_tag(association, index); /* * Convert all tag structure types to generic version, as it * can represent all models. */ if (OCTEON_IS_MODEL(OCTEON_CN58XX) || OCTEON_IS_MODEL(OCTEON_CN56XX)) { tag.s.V = tmp_tag.cn58xx.V; tag.s.D = tmp_tag.cn58xx.D; tag.s.L = tmp_tag.cn58xx.L; tag.s.U = tmp_tag.cn58xx.U; tag.s.addr = tmp_tag.cn58xx.addr; } else if (OCTEON_IS_MODEL(OCTEON_CN38XX)) { tag.s.V = tmp_tag.cn38xx.V; tag.s.D = tmp_tag.cn38xx.D; tag.s.L = tmp_tag.cn38xx.L; tag.s.U = tmp_tag.cn38xx.U; tag.s.addr = tmp_tag.cn38xx.addr; } else if (OCTEON_IS_MODEL(OCTEON_CN31XX) || OCTEON_IS_MODEL(OCTEON_CN52XX)) { tag.s.V = tmp_tag.cn31xx.V; tag.s.D = tmp_tag.cn31xx.D; tag.s.L = tmp_tag.cn31xx.L; tag.s.U = tmp_tag.cn31xx.U; tag.s.addr = tmp_tag.cn31xx.addr; } else if (OCTEON_IS_MODEL(OCTEON_CN30XX)) { tag.s.V = tmp_tag.cn30xx.V; tag.s.D = tmp_tag.cn30xx.D; tag.s.L = tmp_tag.cn30xx.L; tag.s.U = tmp_tag.cn30xx.U; tag.s.addr = tmp_tag.cn30xx.addr; } else if (OCTEON_IS_MODEL(OCTEON_CN50XX)) { tag.s.V = tmp_tag.cn50xx.V; tag.s.D = tmp_tag.cn50xx.D; tag.s.L = tmp_tag.cn50xx.L; tag.s.U = tmp_tag.cn50xx.U; tag.s.addr = tmp_tag.cn50xx.addr; } else { cvmx_dprintf("Unsupported OCTEON Model in %s\n", __func__); } return tag; } uint32_t cvmx_l2c_address_to_index(uint64_t addr) { uint64_t idx = addr >> CVMX_L2C_IDX_ADDR_SHIFT; union cvmx_l2c_cfg l2c_cfg; l2c_cfg.u64 = cvmx_read_csr(CVMX_L2C_CFG); if (l2c_cfg.s.idxalias) { idx ^= ((addr & CVMX_L2C_ALIAS_MASK) >> CVMX_L2C_TAG_ADDR_ALIAS_SHIFT); } idx &= CVMX_L2C_IDX_MASK; return idx; } int cvmx_l2c_get_cache_size_bytes(void) { return cvmx_l2c_get_num_sets() * cvmx_l2c_get_num_assoc() * CVMX_CACHE_LINE_SIZE; } /** * Return log base 2 of the number of sets in the L2 cache * Returns */ int cvmx_l2c_get_set_bits(void) { int l2_set_bits; if (OCTEON_IS_MODEL(OCTEON_CN56XX) || OCTEON_IS_MODEL(OCTEON_CN58XX)) l2_set_bits = 11; /* 2048 sets */ else if (OCTEON_IS_MODEL(OCTEON_CN38XX)) l2_set_bits = 10; /* 1024 sets */ else if (OCTEON_IS_MODEL(OCTEON_CN31XX) || OCTEON_IS_MODEL(OCTEON_CN52XX)) l2_set_bits = 9; /* 512 sets */ else if (OCTEON_IS_MODEL(OCTEON_CN30XX)) l2_set_bits = 8; /* 256 sets */ else if (OCTEON_IS_MODEL(OCTEON_CN50XX)) l2_set_bits = 7; /* 128 sets */ else { cvmx_dprintf("Unsupported OCTEON Model in %s\n", __func__); l2_set_bits = 11; /* 2048 sets */ } return l2_set_bits; } /* Return the number of sets in the L2 Cache */ int cvmx_l2c_get_num_sets(void) { return 1 << cvmx_l2c_get_set_bits(); } /* Return the number of associations in the L2 Cache */ int cvmx_l2c_get_num_assoc(void) { int l2_assoc; if (OCTEON_IS_MODEL(OCTEON_CN56XX) || OCTEON_IS_MODEL(OCTEON_CN52XX) || OCTEON_IS_MODEL(OCTEON_CN58XX) || OCTEON_IS_MODEL(OCTEON_CN50XX) || OCTEON_IS_MODEL(OCTEON_CN38XX)) l2_assoc = 8; else if (OCTEON_IS_MODEL(OCTEON_CN31XX) || OCTEON_IS_MODEL(OCTEON_CN30XX)) l2_assoc = 4; else { cvmx_dprintf("Unsupported OCTEON Model in %s\n", __func__); l2_assoc = 8; } /* Check to see if part of the cache is disabled */ if (cvmx_fuse_read(265)) l2_assoc = l2_assoc >> 2; else if (cvmx_fuse_read(264)) l2_assoc = l2_assoc >> 1; return l2_assoc; } /** * Flush a line from the L2 cache * This should only be called from one core at a time, as this routine * sets the core to the 'debug' core in order to flush the line. * * @assoc: Association (or way) to flush * @index: Index to flush */ void cvmx_l2c_flush_line(uint32_t assoc, uint32_t index) { union cvmx_l2c_dbg l2cdbg; l2cdbg.u64 = 0; l2cdbg.s.ppnum = cvmx_get_core_num(); l2cdbg.s.finv = 1; l2cdbg.s.set = assoc; /* * Enter debug mode, and make sure all other writes complete * before we enter debug mode. */ asm volatile ("sync" : : : "memory"); cvmx_write_csr(CVMX_L2C_DBG, l2cdbg.u64); cvmx_read_csr(CVMX_L2C_DBG); CVMX_PREPARE_FOR_STORE(((1ULL << 63) + (index) * 128), 0); /* Exit debug mode */ asm volatile ("sync" : : : "memory"); cvmx_write_csr(CVMX_L2C_DBG, 0); cvmx_read_csr(CVMX_L2C_DBG); }