diff options
Diffstat (limited to 'drivers/nvmem/stm32-romem.c')
| -rw-r--r-- | drivers/nvmem/stm32-romem.c | 27 |
1 files changed, 21 insertions, 6 deletions
diff --git a/drivers/nvmem/stm32-romem.c b/drivers/nvmem/stm32-romem.c index 354be526897f..d1d03c2ad081 100644 --- a/drivers/nvmem/stm32-romem.c +++ b/drivers/nvmem/stm32-romem.c @@ -19,19 +19,18 @@ #define STM32_SMC_WRITE_SHADOW 0x03 #define STM32_SMC_READ_OTP 0x04 -/* shadow registers offest */ +/* shadow registers offset */ #define STM32MP15_BSEC_DATA0 0x200 -/* 32 (x 32-bits) lower shadow registers */ -#define STM32MP15_BSEC_NUM_LOWER 32 - struct stm32_romem_cfg { int size; + u8 lower; }; struct stm32_romem_priv { void __iomem *base; struct nvmem_config cfg; + u8 lower; }; static int stm32_romem_read(void *context, unsigned int offset, void *buf, @@ -85,7 +84,7 @@ static int stm32_bsec_read(void *context, unsigned int offset, void *buf, for (i = roffset; (i < roffset + rbytes); i += 4) { u32 otp = i >> 2; - if (otp < STM32MP15_BSEC_NUM_LOWER) { + if (otp < priv->lower) { /* read lower data from shadow registers */ val = readl_relaxed( priv->base + STM32MP15_BSEC_DATA0 + i); @@ -133,6 +132,9 @@ static int stm32_bsec_write(void *context, unsigned int offset, void *buf, } } + if (offset + bytes >= priv->lower * 4) + dev_warn(dev, "Update of upper OTPs with ECC protection (word programming, only once)\n"); + return 0; } @@ -158,6 +160,9 @@ static int stm32_romem_probe(struct platform_device *pdev) priv->cfg.dev = dev; priv->cfg.priv = priv; priv->cfg.owner = THIS_MODULE; + priv->cfg.type = NVMEM_TYPE_OTP; + + priv->lower = 0; cfg = (const struct stm32_romem_cfg *) of_match_device(dev->driver->of_match_table, dev)->data; @@ -167,6 +172,7 @@ static int stm32_romem_probe(struct platform_device *pdev) priv->cfg.reg_read = stm32_romem_read; } else { priv->cfg.size = cfg->size; + priv->lower = cfg->lower; priv->cfg.reg_read = stm32_bsec_read; priv->cfg.reg_write = stm32_bsec_write; } @@ -174,8 +180,17 @@ static int stm32_romem_probe(struct platform_device *pdev) return PTR_ERR_OR_ZERO(devm_nvmem_register(dev, &priv->cfg)); } +/* + * STM32MP15 BSEC OTP regions: 4096 OTP bits (with 3072 effective bits) + * => 96 x 32-bits data words + * - Lower: 1K bits, 2:1 redundancy, incremental bit programming + * => 32 (x 32-bits) lower shadow registers = words 0 to 31 + * - Upper: 2K bits, ECC protection, word programming only + * => 64 (x 32-bits) = words 32 to 95 + */ static const struct stm32_romem_cfg stm32mp15_bsec_cfg = { - .size = 384, /* 96 x 32-bits data words */ + .size = 384, + .lower = 32, }; static const struct of_device_id stm32_romem_of_match[] = { |