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 shmobile_init_cntvoff(); 74 75 if (of_machine_is_compatible("renesas,r8a7745") || 76 of_machine_is_compatible("renesas,r8a7792") || 77 of_machine_is_compatible("renesas,r8a7794")) { 78 freq = 260000000 / 8; /* ZS / 8 */ 79 } else { 80 /* At Linux boot time the r8a7790 arch timer comes up 81 * with the counter disabled. Moreover, it may also report 82 * a potentially incorrect fixed 13 MHz frequency. To be 83 * correct these registers need to be updated to use the 84 * frequency EXTAL / 2. 85 */ 86 freq = get_extal_freq() / 2; 87 } 88 89 /* Remap "armgcnt address map" space */ 90 base = ioremap(0xe6080000, PAGE_SIZE); 91 92 /* 93 * Update the timer if it is either not running, or is not at the 94 * right frequency. The timer is only configurable in secure mode 95 * so this avoids an abort if the loader started the timer and 96 * entered the kernel in non-secure mode. 97 */ 98 99 if ((ioread32(base + CNTCR) & 1) == 0 || 100 ioread32(base + CNTFID0) != freq) { 101 /* Update registers with correct frequency */ 102 iowrite32(freq, base + CNTFID0); 103 asm volatile("mcr p15, 0, %0, c14, c0, 0" : : "r" (freq)); 104 105 /* make sure arch timer is started by setting bit 0 of CNTCR */ 106 iowrite32(1, base + CNTCR); 107 } 108 109 iounmap(base); 110 #endif /* CONFIG_ARM_ARCH_TIMER */ 111 112 of_clk_init(NULL); 113 timer_probe(); 114 } 115 116 struct memory_reserve_config { 117 u64 reserved; 118 u64 base, size; 119 }; 120 121 static int __init rcar_gen2_scan_mem(unsigned long node, const char *uname, 122 int depth, void *data) 123 { 124 const char *type = of_get_flat_dt_prop(node, "device_type", NULL); 125 const __be32 *reg, *endp; 126 int l; 127 struct memory_reserve_config *mrc = data; 128 u64 lpae_start = 1ULL << 32; 129 130 /* We are scanning "memory" nodes only */ 131 if (type == NULL || strcmp(type, "memory")) 132 return 0; 133 134 reg = of_get_flat_dt_prop(node, "linux,usable-memory", &l); 135 if (reg == NULL) 136 reg = of_get_flat_dt_prop(node, "reg", &l); 137 if (reg == NULL) 138 return 0; 139 140 endp = reg + (l / sizeof(__be32)); 141 while ((endp - reg) >= (dt_root_addr_cells + dt_root_size_cells)) { 142 u64 base, size; 143 144 base = dt_mem_next_cell(dt_root_addr_cells, ®); 145 size = dt_mem_next_cell(dt_root_size_cells, ®); 146 147 if (base >= lpae_start) 148 continue; 149 150 if ((base + size) >= lpae_start) 151 size = lpae_start - base; 152 153 if (size < mrc->reserved) 154 continue; 155 156 if (base < mrc->base) 157 continue; 158 159 /* keep the area at top near the 32-bit legacy limit */ 160 mrc->base = base + size - mrc->reserved; 161 mrc->size = mrc->reserved; 162 } 163 164 return 0; 165 } 166 167 void __init rcar_gen2_reserve(void) 168 { 169 struct memory_reserve_config mrc; 170 171 /* reserve 256 MiB at the top of the physical legacy 32-bit space */ 172 memset(&mrc, 0, sizeof(mrc)); 173 mrc.reserved = SZ_256M; 174 175 of_scan_flat_dt(rcar_gen2_scan_mem, &mrc); 176 #ifdef CONFIG_DMA_CMA 177 if (mrc.size && memblock_is_region_memory(mrc.base, mrc.size)) { 178 static struct cma *rcar_gen2_dma_contiguous; 179 180 dma_contiguous_reserve_area(mrc.size, mrc.base, 0, 181 &rcar_gen2_dma_contiguous, true); 182 } 183 #endif 184 } 185 186 static const char * const rcar_gen2_boards_compat_dt[] __initconst = { 187 /* 188 * R8A7790 and R8A7791 can't be handled here as long as they need SMP 189 * initialization fallback. 190 */ 191 "renesas,r8a7792", 192 "renesas,r8a7793", 193 "renesas,r8a7794", 194 NULL, 195 }; 196 197 DT_MACHINE_START(RCAR_GEN2_DT, "Generic R-Car Gen2 (Flattened Device Tree)") 198 .init_early = shmobile_init_delay, 199 .init_late = shmobile_init_late, 200 .init_time = rcar_gen2_timer_init, 201 .reserve = rcar_gen2_reserve, 202 .dt_compat = rcar_gen2_boards_compat_dt, 203 MACHINE_END 204 205 static const char * const rz_g1_boards_compat_dt[] __initconst = { 206 "renesas,r8a7743", 207 "renesas,r8a7745", 208 NULL, 209 }; 210 211 DT_MACHINE_START(RZ_G1_DT, "Generic RZ/G1 (Flattened Device Tree)") 212 .init_early = shmobile_init_delay, 213 .init_late = shmobile_init_late, 214 .init_time = rcar_gen2_timer_init, 215 .reserve = rcar_gen2_reserve, 216 .dt_compat = rz_g1_boards_compat_dt, 217 MACHINE_END 218