1 // SPDX-License-Identifier: GPL-2.0+ 2 /* 3 * eFuse driver for Rockchip devices 4 * 5 * Copyright 2017, Theobroma Systems Design und Consulting GmbH 6 * Written by Philipp Tomsich <philipp.tomsich@theobroma-systems.com> 7 */ 8 9 #include <common.h> 10 #include <asm/io.h> 11 #include <command.h> 12 #include <display_options.h> 13 #include <dm.h> 14 #include <linux/bitops.h> 15 #include <linux/delay.h> 16 #include <misc.h> 17 18 #define RK3399_A_SHIFT 16 19 #define RK3399_A_MASK 0x3ff 20 #define RK3399_NFUSES 32 21 #define RK3399_BYTES_PER_FUSE 4 22 #define RK3399_STROBSFTSEL BIT(9) 23 #define RK3399_RSB BIT(7) 24 #define RK3399_PD BIT(5) 25 #define RK3399_PGENB BIT(3) 26 #define RK3399_LOAD BIT(2) 27 #define RK3399_STROBE BIT(1) 28 #define RK3399_CSB BIT(0) 29 30 struct rockchip_efuse_regs { 31 u32 ctrl; /* 0x00 efuse control register */ 32 u32 dout; /* 0x04 efuse data out register */ 33 u32 rf; /* 0x08 efuse redundancy bit used register */ 34 u32 _rsvd0; 35 u32 jtag_pass; /* 0x10 JTAG password */ 36 u32 strobe_finish_ctrl; 37 /* 0x14 efuse strobe finish control register */ 38 }; 39 40 struct rockchip_efuse_platdata { 41 void __iomem *base; 42 struct clk *clk; 43 }; 44 45 #if defined(DEBUG) 46 static int dump_efuses(cmd_tbl_t *cmdtp, int flag, 47 int argc, char * const argv[]) 48 { 49 /* 50 * N.B.: This function is tailored towards the RK3399 and assumes that 51 * there's always 32 fuses x 32 bits (i.e. 128 bytes of data) to 52 * be read. 53 */ 54 55 struct udevice *dev; 56 u8 fuses[128]; 57 int ret; 58 59 /* retrieve the device */ 60 ret = uclass_get_device_by_driver(UCLASS_MISC, 61 DM_GET_DRIVER(rockchip_efuse), &dev); 62 if (ret) { 63 printf("%s: no misc-device found\n", __func__); 64 return 0; 65 } 66 67 ret = misc_read(dev, 0, &fuses, sizeof(fuses)); 68 if (ret < 0) { 69 printf("%s: misc_read failed\n", __func__); 70 return 0; 71 } 72 73 printf("efuse-contents:\n"); 74 print_buffer(0, fuses, 1, 128, 16); 75 76 return 0; 77 } 78 79 U_BOOT_CMD( 80 rk3399_dump_efuses, 1, 1, dump_efuses, 81 "Dump the content of the efuses", 82 "" 83 ); 84 #endif 85 86 static int rockchip_rk3399_efuse_read(struct udevice *dev, int offset, 87 void *buf, int size) 88 { 89 struct rockchip_efuse_platdata *plat = dev_get_platdata(dev); 90 struct rockchip_efuse_regs *efuse = 91 (struct rockchip_efuse_regs *)plat->base; 92 93 unsigned int addr_start, addr_end, addr_offset; 94 u32 out_value; 95 u8 bytes[RK3399_NFUSES * RK3399_BYTES_PER_FUSE]; 96 int i = 0; 97 u32 addr; 98 99 addr_start = offset / RK3399_BYTES_PER_FUSE; 100 addr_offset = offset % RK3399_BYTES_PER_FUSE; 101 addr_end = DIV_ROUND_UP(offset + size, RK3399_BYTES_PER_FUSE); 102 103 /* cap to the size of the efuse block */ 104 if (addr_end > RK3399_NFUSES) 105 addr_end = RK3399_NFUSES; 106 107 writel(RK3399_LOAD | RK3399_PGENB | RK3399_STROBSFTSEL | RK3399_RSB, 108 &efuse->ctrl); 109 udelay(1); 110 for (addr = addr_start; addr < addr_end; addr++) { 111 setbits_le32(&efuse->ctrl, 112 RK3399_STROBE | (addr << RK3399_A_SHIFT)); 113 udelay(1); 114 out_value = readl(&efuse->dout); 115 clrbits_le32(&efuse->ctrl, RK3399_STROBE); 116 udelay(1); 117 118 memcpy(&bytes[i], &out_value, RK3399_BYTES_PER_FUSE); 119 i += RK3399_BYTES_PER_FUSE; 120 } 121 122 /* Switch to standby mode */ 123 writel(RK3399_PD | RK3399_CSB, &efuse->ctrl); 124 125 memcpy(buf, bytes + addr_offset, size); 126 127 return 0; 128 } 129 130 static int rockchip_efuse_read(struct udevice *dev, int offset, 131 void *buf, int size) 132 { 133 return rockchip_rk3399_efuse_read(dev, offset, buf, size); 134 } 135 136 static const struct misc_ops rockchip_efuse_ops = { 137 .read = rockchip_efuse_read, 138 }; 139 140 static int rockchip_efuse_ofdata_to_platdata(struct udevice *dev) 141 { 142 struct rockchip_efuse_platdata *plat = dev_get_platdata(dev); 143 144 plat->base = dev_read_addr_ptr(dev); 145 return 0; 146 } 147 148 static const struct udevice_id rockchip_efuse_ids[] = { 149 { .compatible = "rockchip,rk3399-efuse" }, 150 {} 151 }; 152 153 U_BOOT_DRIVER(rockchip_efuse) = { 154 .name = "rockchip_efuse", 155 .id = UCLASS_MISC, 156 .of_match = rockchip_efuse_ids, 157 .ofdata_to_platdata = rockchip_efuse_ofdata_to_platdata, 158 .platdata_auto_alloc_size = sizeof(struct rockchip_efuse_platdata), 159 .ops = &rockchip_efuse_ops, 160 }; 161