1 // SPDX-License-Identifier: GPL-2.0+
3 * Copyright (C) 2015-2016 Reinhard Pfau <reinhard.pfau@gdsys.cc>
10 #include <asm/arch/cpu.h>
11 #include <asm/arch/efuse.h>
12 #include <asm/arch/soc.h>
13 #include <linux/mbus.h>
15 #if defined(CONFIG_MVEBU_EFUSE_FAKE)
21 #define MBUS_EFUSE_BASE 0xF6000000
22 #define MBUS_EFUSE_SIZE BIT(20)
24 #define MVEBU_EFUSE_CONTROL (MVEBU_REGISTER(0xE4008))
27 MVEBU_EFUSE_CTRL_PROGRAM_ENABLE = (1 << 31),
30 struct mvebu_hd_efuse {
38 static struct mvebu_hd_efuse *efuses =
39 (struct mvebu_hd_efuse *)(MBUS_EFUSE_BASE + 0xF9000);
41 static struct mvebu_hd_efuse efuses[EFUSE_LINE_MAX + 1];
44 static int efuse_initialised;
46 static struct mvebu_hd_efuse *get_efuse_line(int nr)
48 if (nr < 0 || nr > 63 || !efuse_initialised)
54 static void enable_efuse_program(void)
57 setbits_le32(MVEBU_EFUSE_CONTROL, MVEBU_EFUSE_CTRL_PROGRAM_ENABLE);
61 static void disable_efuse_program(void)
64 clrbits_le32(MVEBU_EFUSE_CONTROL, MVEBU_EFUSE_CTRL_PROGRAM_ENABLE);
68 static int do_prog_efuse(struct mvebu_hd_efuse *efuse,
69 struct efuse_val *new_val, u32 mask0, u32 mask1)
73 val.dwords.d[0] = readl(&efuse->bits_31_0);
74 val.dwords.d[1] = readl(&efuse->bits_63_32);
75 val.lock = readl(&efuse->bit64);
80 val.dwords.d[0] |= (new_val->dwords.d[0] & mask0);
81 val.dwords.d[1] |= (new_val->dwords.d[1] & mask1);
82 val.lock |= new_val->lock;
84 writel(val.dwords.d[0], &efuse->bits_31_0);
86 writel(val.dwords.d[1], &efuse->bits_63_32);
88 writel(val.lock, &efuse->bit64);
94 static int prog_efuse(int nr, struct efuse_val *new_val, u32 mask0, u32 mask1)
96 struct mvebu_hd_efuse *efuse;
99 res = mvebu_efuse_init_hw();
103 efuse = get_efuse_line(nr);
110 /* only write a fuse line with lock bit */
114 /* according to specs ECC protection bits must be 0 on write */
115 if (new_val->bytes.d[7] & 0xFE)
118 if (!new_val->dwords.d[0] && !new_val->dwords.d[1] && (mask0 | mask1))
121 enable_efuse_program();
123 res = do_prog_efuse(efuse, new_val, mask0, mask1);
125 disable_efuse_program();
130 int mvebu_efuse_init_hw(void)
134 if (efuse_initialised)
137 ret = mvebu_mbus_add_window_by_id(
138 CPU_TARGET_SATA23_DFX, 0xA, MBUS_EFUSE_BASE, MBUS_EFUSE_SIZE);
143 efuse_initialised = 1;
148 int mvebu_read_efuse(int nr, struct efuse_val *val)
150 struct mvebu_hd_efuse *efuse;
153 res = mvebu_efuse_init_hw();
157 efuse = get_efuse_line(nr);
164 val->dwords.d[0] = readl(&efuse->bits_31_0);
165 val->dwords.d[1] = readl(&efuse->bits_63_32);
166 val->lock = readl(&efuse->bit64);
170 int mvebu_write_efuse(int nr, struct efuse_val *val)
172 return prog_efuse(nr, val, ~0, ~0);
175 int mvebu_lock_efuse(int nr)
177 struct efuse_val val = {
181 return prog_efuse(nr, &val, 0, 0);
185 * wrapper funcs providing the fuse API
187 * we use the following mapping:
188 * "bank" -> eFuse line
189 * "word" -> 0: bits 0-31
194 static struct efuse_val prog_val;
195 static int valid_prog_words;
197 int fuse_read(u32 bank, u32 word, u32 *val)
199 struct efuse_val fuse_line;
202 if (bank < EFUSE_LINE_MIN || bank > EFUSE_LINE_MAX || word > 2)
205 res = mvebu_read_efuse(bank, &fuse_line);
210 *val = fuse_line.dwords.d[word];
212 *val = fuse_line.lock;
217 int fuse_sense(u32 bank, u32 word, u32 *val)
223 int fuse_prog(u32 bank, u32 word, u32 val)
228 * NOTE: Fuse line should be written as whole.
229 * So how can we do that with this API?
230 * For now: remember values for word == 0 and word == 1 and write the
231 * whole line when word == 2.
232 * This implies that we always require all 3 fuse prog cmds (one for
233 * for each word) to write a single fuse line.
234 * Exception is a single write to word 2 which will lock the fuse line.
236 * Hope that will be OK.
239 if (bank < EFUSE_LINE_MIN || bank > EFUSE_LINE_MAX || word > 2)
243 prog_val.dwords.d[word] = val;
244 valid_prog_words |= (1 << word);
245 } else if ((valid_prog_words & 3) == 0 && val) {
246 res = mvebu_lock_efuse(bank);
247 valid_prog_words = 0;
248 } else if ((valid_prog_words & 3) != 3 || !val) {
251 prog_val.lock = val != 0;
252 res = mvebu_write_efuse(bank, &prog_val);
253 valid_prog_words = 0;
259 int fuse_override(u32 bank, u32 word, u32 val)