1 /* 2 * R-Car Generation 2 support 3 * 4 * Copyright (C) 2013 Renesas Solutions Corp. 5 * Copyright (C) 2013 Magnus Damm 6 * Copyright (C) 2014 Ulrich Hecht 7 * 8 * This program is free software; you can redistribute it and/or modify 9 * it under the terms of the GNU General Public License as published by 10 * the Free Software Foundation; version 2 of the License. 11 * 12 * This program is distributed in the hope that it will be useful, 13 * but WITHOUT ANY WARRANTY; without even the implied warranty of 14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 15 * GNU General Public License for more details. 16 */ 17 18 #include <linux/clk-provider.h> 19 #include <linux/clocksource.h> 20 #include <linux/device.h> 21 #include <linux/dma-contiguous.h> 22 #include <linux/io.h> 23 #include <linux/kernel.h> 24 #include <linux/memblock.h> 25 #include <linux/of.h> 26 #include <linux/of_fdt.h> 27 #include <linux/of_platform.h> 28 #include <asm/mach/arch.h> 29 #include "common.h" 30 #include "rcar-gen2.h" 31 32 static const struct of_device_id cpg_matches[] __initconst = { 33 { .compatible = "renesas,rcar-gen2-cpg-clocks", }, 34 { .compatible = "renesas,r8a7743-cpg-mssr", .data = "extal" }, 35 { .compatible = "renesas,r8a7790-cpg-mssr", .data = "extal" }, 36 { .compatible = "renesas,r8a7791-cpg-mssr", .data = "extal" }, 37 { .compatible = "renesas,r8a7793-cpg-mssr", .data = "extal" }, 38 { /* sentinel */ } 39 }; 40 41 static unsigned int __init get_extal_freq(void) 42 { 43 const struct of_device_id *match; 44 struct device_node *cpg, *extal; 45 u32 freq = 20000000; 46 int idx = 0; 47 48 cpg = of_find_matching_node_and_match(NULL, cpg_matches, &match); 49 if (!cpg) 50 return freq; 51 52 if (match->data) 53 idx = of_property_match_string(cpg, "clock-names", match->data); 54 extal = of_parse_phandle(cpg, "clocks", idx); 55 of_node_put(cpg); 56 if (!extal) 57 return freq; 58 59 of_property_read_u32(extal, "clock-frequency", &freq); 60 of_node_put(extal); 61 return freq; 62 } 63 64 #define CNTCR 0 65 #define CNTFID0 0x20 66 67 void __init rcar_gen2_timer_init(void) 68 { 69 #ifdef CONFIG_ARM_ARCH_TIMER 70 void __iomem *base; 71 u32 freq; 72 73 if (of_machine_is_compatible("renesas,r8a7745") || 74 of_machine_is_compatible("renesas,r8a7792") || 75 of_machine_is_compatible("renesas,r8a7794")) { 76 freq = 260000000 / 8; /* ZS / 8 */ 77 /* CNTVOFF has to be initialized either from non-secure 78 * Hypervisor mode or secure Monitor mode with SCR.NS==1. 79 * If TrustZone is enabled then it should be handled by the 80 * secure code. 81 */ 82 asm volatile( 83 " cps 0x16\n" 84 " mrc p15, 0, r1, c1, c1, 0\n" 85 " orr r0, r1, #1\n" 86 " mcr p15, 0, r0, c1, c1, 0\n" 87 " isb\n" 88 " mov r0, #0\n" 89 " mcrr p15, 4, r0, r0, c14\n" 90 " isb\n" 91 " mcr p15, 0, r1, c1, c1, 0\n" 92 " isb\n" 93 " cps 0x13\n" 94 : : : "r0", "r1"); 95 } else { 96 /* At Linux boot time the r8a7790 arch timer comes up 97 * with the counter disabled. Moreover, it may also report 98 * a potentially incorrect fixed 13 MHz frequency. To be 99 * correct these registers need to be updated to use the 100 * frequency EXTAL / 2. 101 */ 102 freq = get_extal_freq() / 2; 103 } 104 105 /* Remap "armgcnt address map" space */ 106 base = ioremap(0xe6080000, PAGE_SIZE); 107 108 /* 109 * Update the timer if it is either not running, or is not at the 110 * right frequency. The timer is only configurable in secure mode 111 * so this avoids an abort if the loader started the timer and 112 * entered the kernel in non-secure mode. 113 */ 114 115 if ((ioread32(base + CNTCR) & 1) == 0 || 116 ioread32(base + CNTFID0) != freq) { 117 /* Update registers with correct frequency */ 118 iowrite32(freq, base + CNTFID0); 119 asm volatile("mcr p15, 0, %0, c14, c0, 0" : : "r" (freq)); 120 121 /* make sure arch timer is started by setting bit 0 of CNTCR */ 122 iowrite32(1, base + CNTCR); 123 } 124 125 iounmap(base); 126 #endif /* CONFIG_ARM_ARCH_TIMER */ 127 128 of_clk_init(NULL); 129 timer_probe(); 130 } 131 132 struct memory_reserve_config { 133 u64 reserved; 134 u64 base, size; 135 }; 136 137 static int __init rcar_gen2_scan_mem(unsigned long node, const char *uname, 138 int depth, void *data) 139 { 140 const char *type = of_get_flat_dt_prop(node, "device_type", NULL); 141 const __be32 *reg, *endp; 142 int l; 143 struct memory_reserve_config *mrc = data; 144 u64 lpae_start = 1ULL << 32; 145 146 /* We are scanning "memory" nodes only */ 147 if (type == NULL || strcmp(type, "memory")) 148 return 0; 149 150 reg = of_get_flat_dt_prop(node, "linux,usable-memory", &l); 151 if (reg == NULL) 152 reg = of_get_flat_dt_prop(node, "reg", &l); 153 if (reg == NULL) 154 return 0; 155 156 endp = reg + (l / sizeof(__be32)); 157 while ((endp - reg) >= (dt_root_addr_cells + dt_root_size_cells)) { 158 u64 base, size; 159 160 base = dt_mem_next_cell(dt_root_addr_cells, ®); 161 size = dt_mem_next_cell(dt_root_size_cells, ®); 162 163 if (base >= lpae_start) 164 continue; 165 166 if ((base + size) >= lpae_start) 167 size = lpae_start - base; 168 169 if (size < mrc->reserved) 170 continue; 171 172 if (base < mrc->base) 173 continue; 174 175 /* keep the area at top near the 32-bit legacy limit */ 176 mrc->base = base + size - mrc->reserved; 177 mrc->size = mrc->reserved; 178 } 179 180 return 0; 181 } 182 183 void __init rcar_gen2_reserve(void) 184 { 185 struct memory_reserve_config mrc; 186 187 /* reserve 256 MiB at the top of the physical legacy 32-bit space */ 188 memset(&mrc, 0, sizeof(mrc)); 189 mrc.reserved = SZ_256M; 190 191 of_scan_flat_dt(rcar_gen2_scan_mem, &mrc); 192 #ifdef CONFIG_DMA_CMA 193 if (mrc.size && memblock_is_region_memory(mrc.base, mrc.size)) { 194 static struct cma *rcar_gen2_dma_contiguous; 195 196 dma_contiguous_reserve_area(mrc.size, mrc.base, 0, 197 &rcar_gen2_dma_contiguous, true); 198 } 199 #endif 200 } 201 202 static const char * const rcar_gen2_boards_compat_dt[] __initconst = { 203 /* 204 * R8A7790 and R8A7791 can't be handled here as long as they need SMP 205 * initialization fallback. 206 */ 207 "renesas,r8a7792", 208 "renesas,r8a7793", 209 "renesas,r8a7794", 210 NULL, 211 }; 212 213 DT_MACHINE_START(RCAR_GEN2_DT, "Generic R-Car Gen2 (Flattened Device Tree)") 214 .init_early = shmobile_init_delay, 215 .init_late = shmobile_init_late, 216 .init_time = rcar_gen2_timer_init, 217 .reserve = rcar_gen2_reserve, 218 .dt_compat = rcar_gen2_boards_compat_dt, 219 MACHINE_END 220 221 static const char * const rz_g1_boards_compat_dt[] __initconst = { 222 "renesas,r8a7743", 223 "renesas,r8a7745", 224 NULL, 225 }; 226 227 DT_MACHINE_START(RZ_G1_DT, "Generic RZ/G1 (Flattened Device Tree)") 228 .init_early = shmobile_init_delay, 229 .init_late = shmobile_init_late, 230 .init_time = rcar_gen2_timer_init, 231 .reserve = rcar_gen2_reserve, 232 .dt_compat = rz_g1_boards_compat_dt, 233 MACHINE_END 234