diff options
Diffstat (limited to 'drivers/st/iwdg')
| -rw-r--r-- | drivers/st/iwdg/stm32_iwdg.c | 157 |
1 files changed, 157 insertions, 0 deletions
diff --git a/drivers/st/iwdg/stm32_iwdg.c b/drivers/st/iwdg/stm32_iwdg.c new file mode 100644 index 0000000..74451d7 --- /dev/null +++ b/drivers/st/iwdg/stm32_iwdg.c @@ -0,0 +1,157 @@ +/* + * Copyright (c) 2017-2021, STMicroelectronics - All Rights Reserved + * + * SPDX-License-Identifier: BSD-3-Clause + */ + +#include <assert.h> +#include <errno.h> +#include <string.h> + +#include <libfdt.h> + +#include <platform_def.h> + +#include <arch_helpers.h> +#include <common/debug.h> +#include <drivers/arm/gicv2.h> +#include <drivers/clk.h> +#include <drivers/delay_timer.h> +#include <drivers/st/stm32_iwdg.h> +#include <drivers/st/stm32mp_clkfunc.h> +#include <lib/mmio.h> +#include <lib/utils.h> +#include <plat/common/platform.h> + +/* IWDG registers offsets */ +#define IWDG_KR_OFFSET 0x00U + +/* Registers values */ +#define IWDG_KR_RELOAD_KEY 0xAAAA + +struct stm32_iwdg_instance { + uintptr_t base; + unsigned long clock; + uint8_t flags; + int num_irq; +}; + +static struct stm32_iwdg_instance stm32_iwdg[IWDG_MAX_INSTANCE]; + +static int stm32_iwdg_get_dt_node(struct dt_node_info *info, int offset) +{ + int node; + + node = dt_get_node(info, offset, DT_IWDG_COMPAT); + if (node < 0) { + if (offset == -1) { + VERBOSE("%s: No IDWG found\n", __func__); + } + return -FDT_ERR_NOTFOUND; + } + + return node; +} + +void stm32_iwdg_refresh(void) +{ + uint8_t i; + + for (i = 0U; i < IWDG_MAX_INSTANCE; i++) { + struct stm32_iwdg_instance *iwdg = &stm32_iwdg[i]; + + /* 0x00000000 is not a valid address for IWDG peripherals */ + if (iwdg->base != 0U) { + clk_enable(iwdg->clock); + + mmio_write_32(iwdg->base + IWDG_KR_OFFSET, + IWDG_KR_RELOAD_KEY); + + clk_disable(iwdg->clock); + } + } +} + +int stm32_iwdg_init(void) +{ + int node = -1; + struct dt_node_info dt_info; + void *fdt; + uint32_t __unused count = 0; + + if (fdt_get_address(&fdt) == 0) { + panic(); + } + + for (node = stm32_iwdg_get_dt_node(&dt_info, node); + node != -FDT_ERR_NOTFOUND; + node = stm32_iwdg_get_dt_node(&dt_info, node)) { + struct stm32_iwdg_instance *iwdg; + uint32_t hw_init; + uint32_t idx; + + count++; + + idx = stm32_iwdg_get_instance(dt_info.base); + iwdg = &stm32_iwdg[idx]; + iwdg->base = dt_info.base; + iwdg->clock = (unsigned long)dt_info.clock; + + /* DT can specify low power cases */ + if (fdt_getprop(fdt, node, "stm32,enable-on-stop", NULL) == + NULL) { + iwdg->flags |= IWDG_DISABLE_ON_STOP; + } + + if (fdt_getprop(fdt, node, "stm32,enable-on-standby", NULL) == + NULL) { + iwdg->flags |= IWDG_DISABLE_ON_STANDBY; + } + + /* Explicit list of supported bit flags */ + hw_init = stm32_iwdg_get_otp_config(idx); + + if ((hw_init & IWDG_HW_ENABLED) != 0) { + if (dt_info.status == DT_DISABLED) { + ERROR("OTP enabled but iwdg%u DT-disabled\n", + idx + 1U); + panic(); + } + iwdg->flags |= IWDG_HW_ENABLED; + } + + if (dt_info.status == DT_DISABLED) { + zeromem((void *)iwdg, + sizeof(struct stm32_iwdg_instance)); + continue; + } + + if ((hw_init & IWDG_DISABLE_ON_STOP) != 0) { + iwdg->flags |= IWDG_DISABLE_ON_STOP; + } + + if ((hw_init & IWDG_DISABLE_ON_STANDBY) != 0) { + iwdg->flags |= IWDG_DISABLE_ON_STANDBY; + } + + VERBOSE("IWDG%u found, %ssecure\n", idx + 1U, + ((dt_info.status & DT_NON_SECURE) != 0) ? + "non-" : ""); + + if ((dt_info.status & DT_NON_SECURE) != 0) { + stm32mp_register_non_secure_periph_iomem(iwdg->base); + } else { + stm32mp_register_secure_periph_iomem(iwdg->base); + } + +#if defined(IMAGE_BL2) + if (stm32_iwdg_shadow_update(idx, iwdg->flags) != BSEC_OK) { + return -1; + } +#endif + } + + VERBOSE("%u IWDG instance%s found\n", count, (count > 1U) ? "s" : ""); + + return 0; +} |