1 /* $NetBSD: ibm4xx_460ex_l2.c,v 1.1 2026/06/19 18:55:23 rkujawa Exp $ */ 2 3 /* 4 * Copyright (c) 2026 The NetBSD Foundation, Inc. 5 * All rights reserved. 6 * 7 * This code is derived from software contributed to The NetBSD Foundation 8 * by Radoslaw Kujawa. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 20 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 21 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 22 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 23 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 24 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 25 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 26 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 27 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 28 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 29 * POSSIBILITY OF SUCH DAMAGE. 30 */ 31 32 /* 33 * AMCC PPC460EX on-chip 256KB L2 cache support 34 */ 35 36 #include <sys/cdefs.h> 37 __KERNEL_RCSID(0, "$NetBSD: ibm4xx_460ex_l2.c,v 1.1 2026/06/19 18:55:23 rkujawa Exp $"); 38 39 #include "opt_ppc4xx.h" 40 41 #include <sys/param.h> 42 #include <sys/systm.h> 43 #include <sys/intr.h> 44 45 #define _POWERPC_BUS_DMA_PRIVATE 46 #include <sys/bus.h> 47 48 #include <powerpc/ibm4xx/cpu.h> 49 #include <powerpc/ibm4xx/amcc460ex.h> 50 #include <powerpc/ibm4xx/ibm4xx_460ex_l2.h> 51 52 #define L2_LINE_SIZE 32 53 #define L2_WAYS 4 54 #define L2_SIZE (256 * 1024) 55 #define L2_INDEX_SPAN (L2_SIZE / L2_WAYS) /* 64KB */ 56 57 bool ibm4xx_460ex_l2_enabled = false; 58 uint32_t ibm4xx_460ex_l2_cfg; 59 60 /* 61 * Build the L2C0_ADDR val for an invalidate command 62 */ 63 static inline uint32_t 64 ibm4xx_460ex_l2_addr(bus_addr_t pa) 65 { 66 return (uint32_t)pa & 0xfffffff0; 67 } 68 69 /* 70 * Invalidate the L2 lines backing the (offset, offset+len) window 71 */ 72 static void 73 ibm4xx_460ex_l2_invalidate(bus_dma_tag_t t, bus_dmamap_t map, 74 bus_addr_t offset, bus_size_t len) 75 { 76 const bus_dma_segment_t *ds = map->dm_segs; 77 int s; 78 79 if (len == 0) 80 return; 81 82 s = splhigh(); 83 84 if (len >= L2_INDEX_SPAN) { 85 /* Window sweeps every index: one whole-cache invalidate. */ 86 mtdcr(DCR_L2C0_ADDR, 0); 87 mtdcr(DCR_L2C0_CMD, L2C_CMD_HCC); 88 while ((mfdcr(DCR_L2C0_SR) & L2C_SR_CC) == 0) 89 ; 90 __asm volatile ("msync" ::: "memory"); 91 splx(s); 92 return; 93 } 94 95 /* Skip leading amount. */ 96 while (offset >= ds->ds_len) { 97 offset -= ds->ds_len; 98 ds++; 99 } 100 for (; len > 0; ds++, offset = 0) { 101 bus_size_t seglen = ds->ds_len - offset; 102 bus_addr_t addr = BUS_MEM_TO_PHYS(t, ds->ds_addr) + offset; 103 bus_addr_t lineoff, epa; 104 105 if (seglen > len) 106 seglen = len; 107 len -= seglen; 108 KASSERT(ds < &map->dm_segs[map->dm_nsegs]); 109 110 /* Realign to cache-line boundaries. */ 111 lineoff = addr & (L2_LINE_SIZE - 1); 112 seglen += lineoff; 113 addr -= lineoff; 114 115 for (epa = addr + seglen; addr < epa; addr += L2_LINE_SIZE) { 116 mtdcr(DCR_L2C0_ADDR, ibm4xx_460ex_l2_addr(addr)); 117 mtdcr(DCR_L2C0_CMD, L2C_CMD_INV); 118 while ((mfdcr(DCR_L2C0_SR) & L2C_SR_CC) == 0) 119 ; 120 } 121 } 122 __asm volatile ("msync" ::: "memory"); 123 splx(s); 124 } 125 126 /* 127 * Private bus_dma sync for the USB controllers. 128 */ 129 static void 130 ibm4xx_460ex_l2_dmamap_sync(bus_dma_tag_t t, bus_dmamap_t map, 131 bus_addr_t offset, bus_size_t len, int ops) 132 { 133 if (ibm4xx_460ex_l2_enabled && (ops & BUS_DMASYNC_POSTREAD) != 0) 134 ibm4xx_460ex_l2_invalidate(t, map, offset, len); 135 _bus_dmamap_sync(t, map, offset, len, ops); 136 } 137 138 /* 139 * A clone of ibm4xx_default_bus_dma_tag sync overriden 140 */ 141 struct powerpc_bus_dma_tag ibm4xx_460ex_l2_bus_dma_tag = { 142 0, 0, 143 _bus_dmamap_create, 144 _bus_dmamap_destroy, 145 _bus_dmamap_load, 146 _bus_dmamap_load_mbuf, 147 _bus_dmamap_load_uio, 148 _bus_dmamap_load_raw, 149 _bus_dmamap_unload, 150 ibm4xx_460ex_l2_dmamap_sync, 151 _bus_dmamem_alloc, 152 _bus_dmamem_free, 153 _bus_dmamem_map, 154 _bus_dmamem_unmap, 155 _bus_dmamem_mmap, 156 _bus_dma_phys_to_bus_mem_generic, 157 _bus_dma_bus_mem_to_phys_generic, 158 }; 159 160 bus_dma_tag_t 161 ibm4xx_460ex_l2_dmatag(void) 162 { 163 return &ibm4xx_460ex_l2_bus_dma_tag; 164 } 165 166 void 167 ibm4xx_460ex_l2cache_enable(u_int memsize) 168 { 169 uint32_t snpsz; 170 u_int code; 171 172 /* Hand the SRAM0 data arrays back from the SRAM controller. */ 173 mtdcr(DCR_SRAM0_SB0CR, 0); 174 mtdcr(DCR_SRAM0_SB1CR, 0); 175 mtdcr(DCR_SRAM0_SB2CR, 0); 176 mtdcr(DCR_SRAM0_SB3CR, 0); 177 178 /* RDBW is required; switch the array into L2 mode. */ 179 mtdcr(DCR_L2C0_CFG, L2C_CFG_RDBW | L2C_CFG_L2M | L2C_CFG_SS_256KB); 180 181 /* Reset the tag array with the hardware clear command. */ 182 mtdcr(DCR_L2C0_ADDR, 0); 183 mtdcr(DCR_L2C0_CMD, L2C_CMD_HCC); 184 while ((mfdcr(DCR_L2C0_SR) & L2C_SR_CC) == 0) 185 ; 186 /* Clear any latched cache- and tag-parity errors. */ 187 mtdcr(DCR_L2C0_CMD, L2C_CMD_CCP); 188 while ((mfdcr(DCR_L2C0_SR) & L2C_SR_CC) == 0) 189 ; 190 mtdcr(DCR_L2C0_CMD, L2C_CMD_CTE); 191 while ((mfdcr(DCR_L2C0_SR) & L2C_SR_CC) == 0) 192 ; 193 __asm volatile ("msync" ::: "memory"); 194 195 /* 196 * Program snoop region 0 to cover all of DRAM on the LL segment! 197 */ 198 snpsz = 0x100000; /* 1MB, the smallest snoop region */ 199 code = 0; 200 while (snpsz < memsize) { 201 snpsz <<= 1; 202 code++; 203 } 204 mtdcr(DCR_L2C0_SNP0, (code << L2C_SNP_SSR_SHIFT) | L2C_SNP_ESR); 205 mtdcr(DCR_L2C0_SNP1, 0); 206 207 /* Enable instruction- and data-side L2 caching. */ 208 mtdcr(DCR_L2C0_CFG, L2C_CFG_RDBW | L2C_CFG_L2M | L2C_CFG_SS_256KB | 209 L2C_CFG_FRAN | L2C_CFG_SNPCI | L2C_CFG_ICU | L2C_CFG_DCU); 210 __asm volatile ("msync" ::: "memory"); 211 212 /* Read back so the caller can confirm what actually stuck. */ 213 ibm4xx_460ex_l2_cfg = mfdcr(DCR_L2C0_CFG); 214 if (ibm4xx_460ex_l2_cfg & L2C_CFG_L2M) 215 ibm4xx_460ex_l2_enabled = true; 216 } 217 218
Indexes created Tue Jul 07 00:25:39 UTC 2026