|  | # STM32 entropy generator driver configuration | 
|  |  | 
|  | # Copyright (c) 2017 Erwin Rol <erwin@erwinrol.com> | 
|  | # SPDX-License-Identifier: Apache-2.0 | 
|  |  | 
|  | menuconfig ENTROPY_STM32_RNG | 
|  | bool "STM32 RNG driver" | 
|  | default y | 
|  | depends on DT_HAS_ST_STM32_RNG_ENABLED | 
|  | select ENTROPY_HAS_DRIVER | 
|  | select USE_STM32_LL_RNG | 
|  | help | 
|  | This option enables the RNG processor, which is a entropy number | 
|  | generator, based on a continuous analog noise, that provides | 
|  | a entropy 32-bit value to the host when read. It is available for | 
|  | F4 (except STM32F401 & STM32F411), L4, F7, H7 and G4 series. | 
|  |  | 
|  | if ENTROPY_STM32_RNG | 
|  |  | 
|  | config ENTROPY_STM32_THR_POOL_SIZE | 
|  | int "Thread-mode random number pool size" | 
|  | range ENTROPY_STM32_THR_THRESHOLD 256 | 
|  | default 8 | 
|  | help | 
|  | Buffer length in bytes used to store entropy bytes generated by the | 
|  | hardware to make them ready for thread mode consumers. | 
|  | Please note, that size of the pool must be a power of 2. | 
|  |  | 
|  | config ENTROPY_STM32_THR_THRESHOLD | 
|  | int "Thread-mode random number pool low-water threshold" | 
|  | range 4 255 | 
|  | help | 
|  | Low water-mark threshold in bytes to trigger entropy generation for | 
|  | thread mode consumers. As soon as the number of available bytes in the | 
|  | buffer goes below this number hardware entropy generation will be | 
|  | started. | 
|  |  | 
|  | config ENTROPY_STM32_ISR_POOL_SIZE | 
|  | int "ISR-mode random number pool size" | 
|  | range ENTROPY_STM32_ISR_THRESHOLD 256 | 
|  | default 16 | 
|  | help | 
|  | Buffer length in bytes used to store entropy bytes generated by the | 
|  | hardware to make them ready for ISR consumers. | 
|  | Please note, that size of the pool must be a power of 2. | 
|  |  | 
|  | config ENTROPY_STM32_ISR_THRESHOLD | 
|  | int "ISR-mode random number pool low-water threshold" | 
|  | range 12 255 | 
|  | help | 
|  | Low water-mark threshold in bytes to trigger entropy generation for | 
|  | ISR consumers. As soon as the number of available bytes in the | 
|  | buffer goes below this number hardware entropy generation will be | 
|  | started. | 
|  |  | 
|  | config ENTROPY_STM32_CLK_CHECK | 
|  | bool "Runtime clock configuration check" | 
|  | default y | 
|  | help | 
|  | Enables a check on RNG clock configuration. Correct clock | 
|  | configuration depends on STM32 series. Check reference manual if an | 
|  | error is reported. | 
|  | This check assumes CED (Clock Error Detected) bit is enabled (when | 
|  | available, CED is enabeld by default). Disable this check if CED is | 
|  | disabled. | 
|  |  | 
|  | endif # ENTROPY_STM32_RNG |