diff options
Diffstat (limited to 'drivers/nvmem/stm32-romem.c')
| -rw-r--r-- | drivers/nvmem/stm32-romem.c | 84 |
1 files changed, 81 insertions, 3 deletions
diff --git a/drivers/nvmem/stm32-romem.c b/drivers/nvmem/stm32-romem.c index d1d03c2ad081..ba779e26937a 100644 --- a/drivers/nvmem/stm32-romem.c +++ b/drivers/nvmem/stm32-romem.c @@ -11,6 +11,9 @@ #include <linux/module.h> #include <linux/nvmem-provider.h> #include <linux/of_device.h> +#include <linux/tee_drv.h> + +#include "stm32-bsec-optee-ta.h" /* BSEC secure service access from non-secure */ #define STM32_SMC_BSEC 0x82001003 @@ -25,12 +28,14 @@ struct stm32_romem_cfg { int size; u8 lower; + bool ta; }; struct stm32_romem_priv { void __iomem *base; struct nvmem_config cfg; u8 lower; + struct tee_context *ctx; }; static int stm32_romem_read(void *context, unsigned int offset, void *buf, @@ -138,12 +143,54 @@ static int stm32_bsec_write(void *context, unsigned int offset, void *buf, return 0; } +static int stm32_bsec_pta_read(void *context, unsigned int offset, void *buf, + size_t bytes) +{ + struct stm32_romem_priv *priv = context; + + return stm32_bsec_optee_ta_read(priv->ctx, offset, buf, bytes); +} + +static int stm32_bsec_pta_write(void *context, unsigned int offset, void *buf, + size_t bytes) +{ + struct stm32_romem_priv *priv = context; + + return stm32_bsec_optee_ta_write(priv->ctx, priv->lower, offset, buf, bytes); +} + +static bool stm32_bsec_smc_check(void) +{ + u32 val; + int ret; + + /* check that the OP-TEE support the BSEC SMC (legacy mode) */ + ret = stm32_bsec_smc(STM32_SMC_READ_SHADOW, 0, 0, &val); + + return !ret; +} + +static bool optee_presence_check(void) +{ + struct device_node *np; + bool tee_detected = false; + + /* check that the OP-TEE node is present and available. */ + np = of_find_compatible_node(NULL, NULL, "linaro,optee-tz"); + if (np && of_device_is_available(np)) + tee_detected = true; + of_node_put(np); + + return tee_detected; +} + static int stm32_romem_probe(struct platform_device *pdev) { const struct stm32_romem_cfg *cfg; struct device *dev = &pdev->dev; struct stm32_romem_priv *priv; struct resource *res; + int rc; priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL); if (!priv) @@ -173,15 +220,36 @@ static int stm32_romem_probe(struct platform_device *pdev) } else { priv->cfg.size = cfg->size; priv->lower = cfg->lower; - priv->cfg.reg_read = stm32_bsec_read; - priv->cfg.reg_write = stm32_bsec_write; + if (cfg->ta || optee_presence_check()) { + rc = stm32_bsec_optee_ta_open(&priv->ctx); + if (rc) { + /* wait for OP-TEE client driver to be up and ready */ + if (rc == -EPROBE_DEFER) + return -EPROBE_DEFER; + /* BSEC PTA is required or SMC not supported */ + if (cfg->ta || !stm32_bsec_smc_check()) + return rc; + } + } + if (priv->ctx) { + rc = devm_add_action_or_reset(dev, stm32_bsec_optee_ta_close, priv->ctx); + if (rc) { + dev_err(dev, "devm_add_action_or_reset() failed (%d)\n", rc); + return rc; + } + priv->cfg.reg_read = stm32_bsec_pta_read; + priv->cfg.reg_write = stm32_bsec_pta_write; + } else { + priv->cfg.reg_read = stm32_bsec_read; + priv->cfg.reg_write = stm32_bsec_write; + } } return PTR_ERR_OR_ZERO(devm_nvmem_register(dev, &priv->cfg)); } /* - * STM32MP15 BSEC OTP regions: 4096 OTP bits (with 3072 effective bits) + * STM32MP15/13 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 @@ -191,6 +259,13 @@ static int stm32_romem_probe(struct platform_device *pdev) static const struct stm32_romem_cfg stm32mp15_bsec_cfg = { .size = 384, .lower = 32, + .ta = false, +}; + +static const struct stm32_romem_cfg stm32mp13_bsec_cfg = { + .size = 384, + .lower = 32, + .ta = true, }; static const struct of_device_id stm32_romem_of_match[] = { @@ -198,7 +273,10 @@ static const struct of_device_id stm32_romem_of_match[] = { .compatible = "st,stm32mp15-bsec", .data = (void *)&stm32mp15_bsec_cfg, }, { + .compatible = "st,stm32mp13-bsec", + .data = (void *)&stm32mp13_bsec_cfg, }, + { /* sentinel */ }, }; MODULE_DEVICE_TABLE(of, stm32_romem_of_match); |