1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * R-Car Generation 2 support 4 * 5 * Copyright (C) 2013 Renesas Solutions Corp. 6 * Copyright (C) 2013 Magnus Damm 7 * Copyright (C) 2014 Ulrich Hecht 8 */ 9 10 #include <linux/clocksource.h> 11 #include <linux/io.h> 12 #include <linux/kernel.h> 13 #include <linux/memblock.h> 14 #include <linux/of.h> 15 #include <linux/of_clk.h> 16 #include <linux/psci.h> 17 #include <asm/mach/arch.h> 18 #include <asm/secure_cntvoff.h> 19 #include "common.h" 20 21 static const struct of_device_id cpg_matches[] __initconst = { 22 { .compatible = "renesas,r8a7742-cpg-mssr", .data = "extal" }, 23 { .compatible = "renesas,r8a7743-cpg-mssr", .data = "extal" }, 24 { .compatible = "renesas,r8a7744-cpg-mssr", .data = "extal" }, 25 { .compatible = "renesas,r8a7790-cpg-mssr", .data = "extal" }, 26 { .compatible = "renesas,r8a7791-cpg-mssr", .data = "extal" }, 27 { .compatible = "renesas,r8a7793-cpg-mssr", .data = "extal" }, 28 { /* sentinel */ } 29 }; 30 31 static unsigned int __init get_extal_freq(void) 32 { 33 const struct of_device_id *match; 34 struct device_node *cpg, *extal; 35 u32 freq = 20000000; 36 int idx = 0; 37 38 cpg = of_find_matching_node_and_match(NULL, cpg_matches, &match); 39 if (!cpg) 40 return freq; 41 42 if (match->data) 43 idx = of_property_match_string(cpg, "clock-names", match->data); 44 extal = of_parse_phandle(cpg, "clocks", idx); 45 of_node_put(cpg); 46 if (!extal) 47 return freq; 48 49 of_property_read_u32(extal, "clock-frequency", &freq); 50 of_node_put(extal); 51 return freq; 52 } 53 54 #define CNTCR 0 55 #define CNTFID0 0x20 56 57 static void __init rcar_gen2_timer_init(void) 58 { 59 bool need_update = true; 60 void __iomem *base; 61 u32 freq; 62 63 /* 64 * If PSCI is available then most likely we are running on PSCI-enabled 65 * U-Boot which, we assume, has already taken care of resetting CNTVOFF 66 * and updating counter module before switching to non-secure mode 67 * and we don't need to. 68 */ 69 #ifdef CONFIG_ARM_PSCI_FW 70 if (psci_ops.cpu_on) 71 need_update = false; 72 #endif 73 74 if (need_update == false) 75 goto skip_update; 76 77 secure_cntvoff_init(); 78 79 if (of_machine_is_compatible("renesas,r8a7745") || 80 of_machine_is_compatible("renesas,r8a77470") || 81 of_machine_is_compatible("renesas,r8a7792") || 82 of_machine_is_compatible("renesas,r8a7794")) { 83 freq = 260000000 / 8; /* ZS / 8 */ 84 } else { 85 /* At Linux boot time the r8a7790 arch timer comes up 86 * with the counter disabled. Moreover, it may also report 87 * a potentially incorrect fixed 13 MHz frequency. To be 88 * correct these registers need to be updated to use the 89 * frequency EXTAL / 2. 90 */ 91 freq = get_extal_freq() / 2; 92 } 93 94 /* Remap "armgcnt address map" space */ 95 base = ioremap(0xe6080000, PAGE_SIZE); 96 97 /* 98 * Update the timer if it is either not running, or is not at the 99 * right frequency. The timer is only configurable in secure mode 100 * so this avoids an abort if the loader started the timer and 101 * entered the kernel in non-secure mode. 102 */ 103 104 if ((ioread32(base + CNTCR) & 1) == 0 || 105 ioread32(base + CNTFID0) != freq) { 106 /* Update registers with correct frequency */ 107 iowrite32(freq, base + CNTFID0); 108 asm volatile("mcr p15, 0, %0, c14, c0, 0" : : "r" (freq)); 109 110 /* make sure arch timer is started by setting bit 0 of CNTCR */ 111 iowrite32(1, base + CNTCR); 112 } 113 114 iounmap(base); 115 116 skip_update: 117 of_clk_init(NULL); 118 timer_probe(); 119 } 120 121 static const char * const rcar_gen2_boards_compat_dt[] __initconst = { 122 "renesas,r8a7790", 123 "renesas,r8a7791", 124 "renesas,r8a7792", 125 "renesas,r8a7793", 126 "renesas,r8a7794", 127 NULL 128 }; 129 130 DT_MACHINE_START(RCAR_GEN2_DT, "Generic R-Car Gen2 (Flattened Device Tree)") 131 .init_late = shmobile_init_late, 132 .init_time = rcar_gen2_timer_init, 133 .dt_compat = rcar_gen2_boards_compat_dt, 134 MACHINE_END 135 136 static const char * const rz_g1_boards_compat_dt[] __initconst = { 137 "renesas,r8a7742", 138 "renesas,r8a7743", 139 "renesas,r8a7744", 140 "renesas,r8a7745", 141 "renesas,r8a77470", 142 NULL 143 }; 144 145 DT_MACHINE_START(RZ_G1_DT, "Generic RZ/G1 (Flattened Device Tree)") 146 .init_late = shmobile_init_late, 147 .init_time = rcar_gen2_timer_init, 148 .dt_compat = rz_g1_boards_compat_dt, 149 MACHINE_END 150