driver: misc: imx8ulp: Add fuse driver for imx8ulp

This driver uses FSB to read some fuses, but not support program fuse.
It only works in SPL (secure mode), u-boot needs traps to ATF to
read them.

Some fuses can read from S400 API and others are from FSB.
Also support program some fuses via S400 API

Signed-off-by: Ye Li <ye.li@nxp.com>

diff --git a/drivers/misc/imx8ulp/Makefile b/drivers/misc/imx8ulp/Makefile
index 1d79241..927cc55 100644 (file)
--- a/drivers/misc/imx8ulp/Makefile
+++ b/drivers/misc/imx8ulp/Makefile
@@ -1,3 +1,4 @@
 # SPDX-License-Identifier: GPL-2.0+
 
 obj-y += s400_api.o imx8ulp_mu.o
+obj-$(CONFIG_CMD_FUSE) += fuse.o

diff --git a/drivers/misc/imx8ulp/fuse.c b/drivers/misc/imx8ulp/fuse.c
new file mode 100644 (file)
index 0000000..d1feb62
--- /dev/null
+++ b/drivers/misc/imx8ulp/fuse.c
@@ -0,0 +1,198 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright 2020 NXP
+ */
+
+#include <common.h>
+#include <console.h>
+#include <errno.h>
+#include <fuse.h>
+#include <asm/arch/sys_proto.h>
+#include <asm/arch/imx-regs.h>
+#include <env.h>
+#include <asm/arch/s400_api.h>
+#include <asm/global_data.h>
+
+DECLARE_GLOBAL_DATA_PTR;
+
+#define FUSE_BANKS     64
+#define WORDS_PER_BANKS 8
+
+struct fsb_map_entry {
+       s32 fuse_bank;
+       u32 fuse_words;
+       bool redundancy;
+};
+
+struct s400_map_entry {
+       s32 fuse_bank;
+       u32 fuse_words;
+       u32 fuse_offset;
+       u32 s400_index;
+};
+
+struct fsb_map_entry fsb_mapping_table[] = {
+       { 3, 8 },
+       { 4, 8 },
+       { 5, 8 },
+       { 6, 8 },
+       { -1, 48 }, /* Reserve 48 words */
+       { 8,  4, true },
+       { 24, 4, true },
+       { 26, 4, true },
+       { 27, 4, true },
+       { 28, 8 },
+       { 29, 8 },
+       { 30, 8 },
+       { 31, 8 },
+       { 37, 8 },
+       { 38, 8 },
+       { 39, 8 },
+       { 40, 8 },
+       { 41, 8 },
+       { 42, 8 },
+       { 43, 8 },
+       { 44, 8 },
+       { 45, 8 },
+       { 46, 8 },
+};
+
+struct s400_map_entry s400_api_mapping_table[] = {
+       { 1, 8 },       /* LOCK */
+       { 2, 8 },       /* ECID */
+       { 7, 4, 0, 1 }, /* OTP_UNIQ_ID */
+       { 23, 1, 4, 2 }, /* OTFAD */
+};
+
+static s32 map_fsb_fuse_index(u32 bank, u32 word, bool *redundancy)
+{
+       s32 size = ARRAY_SIZE(fsb_mapping_table);
+       s32 i, word_pos = 0;
+
+       /* map the fuse from ocotp fuse map to FSB*/
+       for (i = 0; i < size; i++) {
+               if (fsb_mapping_table[i].fuse_bank != -1 &&
+                   fsb_mapping_table[i].fuse_bank == bank) {
+                       break;
+               }
+
+               word_pos += fsb_mapping_table[i].fuse_words;
+       }
+
+       if (i == size)
+               return -1; /* Failed to find */
+
+       if (fsb_mapping_table[i].redundancy) {
+               *redundancy = true;
+               return (word >> 1) + word_pos;
+       }
+
+       *redundancy = false;
+       return word + word_pos;
+}
+
+static s32 map_s400_fuse_index(u32 bank, u32 word)
+{
+       s32 size = ARRAY_SIZE(s400_api_mapping_table);
+       s32 i;
+
+       /* map the fuse from ocotp fuse map to FSB*/
+       for (i = 0; i < size; i++) {
+               if (s400_api_mapping_table[i].fuse_bank != -1 &&
+                   s400_api_mapping_table[i].fuse_bank == bank) {
+                       if (word >= s400_api_mapping_table[i].fuse_offset &&
+                           word < (s400_api_mapping_table[i].fuse_offset +
+                           s400_api_mapping_table[i].fuse_words))
+                               break;
+               }
+       }
+
+       if (i == size)
+               return -1; /* Failed to find */
+
+       if (s400_api_mapping_table[i].s400_index != 0)
+               return s400_api_mapping_table[i].s400_index;
+
+       return s400_api_mapping_table[i].fuse_bank * 8 + word;
+}
+
+int fuse_sense(u32 bank, u32 word, u32 *val)
+{
+       s32 word_index;
+       bool redundancy;
+
+       if (bank >= FUSE_BANKS || word >= WORDS_PER_BANKS || !val)
+               return -EINVAL;
+
+       word_index = map_fsb_fuse_index(bank, word, &redundancy);
+       if (word_index >= 0) {
+               *val = readl((ulong)FSB_BASE_ADDR + 0x800 + (word_index << 2));
+               if (redundancy)
+                       *val = (*val >> ((word % 2) * 16)) & 0xFFFF;
+
+               return 0;
+       }
+
+       word_index = map_s400_fuse_index(bank, word);
+       if (word_index >= 0) {
+               u32 data[4];
+               u32 res, size = 4;
+               int ret;
+
+               /* Only UID return 4 words */
+               if (word_index != 1)
+                       size = 1;
+
+               ret = ahab_read_common_fuse(word_index, data, size, &res);
+               if (ret) {
+                       printf("ahab read fuse failed %d, 0x%x\n", ret, res);
+                       return ret;
+               }
+
+               if (word_index == 1) {
+                       *val = data[word]; /* UID */
+               } else if (word_index == 2) {
+                       /*
+                        * OTFAD 3 bits as follow:
+                        * bit 0: OTFAD_ENABLE
+                        * bit 1: OTFAD_DISABLE_OVERRIDE
+                        * bit 2: KEY_BLOB_EN
+                        */
+                       *val = data[0] << 3;
+               } else {
+                       *val = data[0];
+               }
+
+               return 0;
+       }
+
+       return -ENOENT;
+}
+
+int fuse_read(u32 bank, u32 word, u32 *val)
+{
+       return fuse_sense(bank, word, val);
+}
+
+int fuse_prog(u32 bank, u32 word, u32 val)
+{
+       u32 res;
+       int ret;
+
+       if (bank >= FUSE_BANKS || word >= WORDS_PER_BANKS || !val)
+               return -EINVAL;
+
+       ret = ahab_write_fuse((bank * 8 + word), val, false, &res);
+       if (ret) {
+               printf("ahab write fuse failed %d, 0x%x\n", ret, res);
+               return ret;
+       }
+
+       return 0;
+}
+
+int fuse_override(u32 bank, u32 word, u32 val)
+{
+       printf("Override fuse to i.MX8ULP in u-boot is forbidden\n");
+       return -EPERM;
+}