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soburikartben
soburi
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kartben
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drivers: entropy: add iproc_rng200 (rpi_5) random generator driver
Add driver for iproc_rng200 entropy generator. This device is used by rpi_5. Signed-off-by: TOKITA Hiroshi <tokita.hiroshi@gmail.com>
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‎boards/raspberrypi/rpi_5/rpi_5.dts

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zephyr,console = &uart10;
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zephyr,shell-uart = &uart10;
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zephyr,pcie-controller = &pcie1;
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zephyr,entropy = &rng;
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};
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leds {

‎drivers/entropy/CMakeLists.txt

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zephyr_library_sources_ifdef(CONFIG_USERSPACE entropy_handlers.c)
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# zephyr-keep-sorted-start
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zephyr_library_sources_ifdef(CONFIG_ENTROPY_BRCM_IPROC_RNG200 entropy_iproc_rng200.c)
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zephyr_library_sources_ifdef(CONFIG_ENTROPY_BT_HCI entropy_bt_hci.c)
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zephyr_library_sources_ifdef(CONFIG_ENTROPY_CC13XX_CC26XX_RNG entropy_cc13xx_cc26xx.c)
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zephyr_library_sources_ifdef(CONFIG_ENTROPY_ESP32_RNG entropy_esp32.c)

‎drivers/entropy/Kconfig

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@@ -26,6 +26,7 @@ source "drivers/entropy/Kconfig.bt_hci"
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source "drivers/entropy/Kconfig.cc13xx_cc26xx"
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source "drivers/entropy/Kconfig.esp32"
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source "drivers/entropy/Kconfig.gecko"
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source "drivers/entropy/Kconfig.iproc"
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source "drivers/entropy/Kconfig.litex"
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source "drivers/entropy/Kconfig.max32"
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source "drivers/entropy/Kconfig.maxq10xx"

‎drivers/entropy/Kconfig.iproc

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# Copyright (c) 2025 TOKITA Hiroshi
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# SPDX-License-Identifier: Apache-2.0
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config ENTROPY_BRCM_IPROC_RNG200
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bool "Broadcom iProc RNG200 driver"
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default y
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depends on DT_HAS_BRCM_IPROC_RNG200_ENABLED
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select ENTROPY_HAS_DRIVER
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help
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Enable the Broadcom iProc RNG200 random number generator

‎drivers/entropy/entropy_iproc_rng200.c

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/*
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* Copyright (c) 2025 TOKITA Hiroshi
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*
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* SPDX-License-Identifier: Apache-2.0
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*/
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#define DT_DRV_COMPAT brcm_iproc_rng200
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#include <zephyr/logging/log.h>
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LOG_MODULE_REGISTER(iproc_rng200_entropy, CONFIG_ENTROPY_LOG_LEVEL);
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#include <zephyr/device.h>
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#include <zephyr/drivers/entropy.h>
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#include <errno.h>
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#include <zephyr/init.h>
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#include <zephyr/kernel.h>
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#define IPROC_RNG200_CTRL_OFFS 0x00
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#define IPROC_RNG200_RNG_RESET_OFFS 0x04
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#define IPROC_RNG200_RBG_RESET_OFFS 0x08
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#define IPROC_RNG200_RESERVED1_OFFS 0x0c
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#define IPROC_RNG200_RESERVED2_OFFS 0x10
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#define IPROC_RNG200_RESERVED3_OFFS 0x14
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#define IPROC_RNG200_INT_STATUS_OFFS 0x18
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#define IPROC_RNG200_RESERVED4_OFFS 0x1c
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#define IPROC_RNG200_FIFO_DATA_OFFS 0x20
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#define IPROC_RNG200_FIFO_COUNT_OFFS 0x24
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#define IPROC_RNG200_CTRL_RBG_EN BIT(0)
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#define IPROC_RNG200_RESET_EN BIT(0)
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#define IPROC_RNG200_INT_STATUS_NIST_FAIL BIT(5)
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#define IPROC_RNG200_INT_STATUS_MASTER_FAIL_LOCKOUT BIT(31)
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#define IPROC_RNG200_CTRL_RBG_EN_MASK BIT_MASK(13)
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#define IPROC_RNG200_FIFO_COUNT_MASK BIT_MASK(8)
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/* time needed to fill fifo when empty */
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#define IPROC_RNG200_FIFO_REFILL_TIME_USEC 40
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#define IPROC_RNG200_FIFO_REFILL_MAX_RETRIES 5
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#define DEV_CFG(dev) ((const struct iproc_rng200_config *)(dev)->config)
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#define DEV_DATA(dev) ((struct iproc_rng200_data *)(dev)->data)
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struct iproc_rng200_config {
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DEVICE_MMIO_NAMED_ROM(base_addr);
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};
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struct iproc_rng200_data {
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DEVICE_MMIO_NAMED_RAM(base_addr);
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struct k_mutex mutex;
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};
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static int iproc_rng200_driver_init(const struct device *dev)
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{
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struct iproc_rng200_data *const data = dev->data;
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k_mutex_init(&data->mutex);
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DEVICE_MMIO_NAMED_MAP(dev, base_addr, K_MEM_CACHE_NONE);
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const mem_addr_t base = DEVICE_MMIO_NAMED_GET(dev, base_addr);
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const uint32_t val =
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sys_read32(base + IPROC_RNG200_CTRL_OFFS) & IPROC_RNG200_CTRL_RBG_EN_MASK;
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sys_write32(val & ~IPROC_RNG200_CTRL_RBG_EN, base + IPROC_RNG200_CTRL_OFFS);
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return 0;
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}
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static int iproc_rng200_driver_get_entropy(const struct device *dev, uint8_t *buffer,
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uint16_t length)
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{
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const mem_addr_t base = DEVICE_MMIO_NAMED_GET(dev, base_addr);
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const uint32_t word_count = DIV_ROUND_UP(length, 4);
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struct iproc_rng200_data *const data = dev->data;
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uint32_t retries_left;
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uint32_t random_word;
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for (uint32_t i = 0; i < word_count; i++) {
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retries_left = IPROC_RNG200_FIFO_REFILL_MAX_RETRIES;
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k_mutex_lock(&data->mutex, K_FOREVER);
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while (true) {
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const uint32_t status = sys_read32(base + IPROC_RNG200_INT_STATUS_OFFS);
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uint32_t val;
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if (status & (IPROC_RNG200_INT_STATUS_MASTER_FAIL_LOCKOUT |
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IPROC_RNG200_INT_STATUS_NIST_FAIL)) {
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sys_write32(0xFFFFFFFF, base + IPROC_RNG200_INT_STATUS_OFFS);
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val = sys_read32(base + IPROC_RNG200_RNG_RESET_OFFS);
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sys_write32(val | IPROC_RNG200_RESET_EN,
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base + IPROC_RNG200_RNG_RESET_OFFS);
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val = sys_read32(base + IPROC_RNG200_RBG_RESET_OFFS);
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sys_write32(val | IPROC_RNG200_RESET_EN,
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base + IPROC_RNG200_RBG_RESET_OFFS);
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val = sys_read32(base + IPROC_RNG200_RNG_RESET_OFFS);
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sys_write32(val & ~IPROC_RNG200_RESET_EN,
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base + IPROC_RNG200_RNG_RESET_OFFS);
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val = sys_read32(base + IPROC_RNG200_RBG_RESET_OFFS);
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sys_write32(val & ~IPROC_RNG200_RESET_EN,
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base + IPROC_RNG200_RBG_RESET_OFFS);
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}
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/* make sure fifo has at least one random word */
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const uint32_t fcnt = sys_read32(base + IPROC_RNG200_FIFO_COUNT_OFFS);
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if ((fcnt & IPROC_RNG200_FIFO_COUNT_MASK) > 0) {
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/* get new random word */
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random_word = sys_read32(base + IPROC_RNG200_FIFO_DATA_OFFS);
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break;
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}
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/* currently no random values available, thus wait */
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retries_left--;
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if (!retries_left) {
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/* number of retries exhausted, give up */
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k_mutex_unlock(&data->mutex);
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return -ETIMEDOUT;
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}
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k_sleep(K_USEC(IPROC_RNG200_FIFO_REFILL_TIME_USEC));
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}
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k_mutex_unlock(&data->mutex);
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memcpy(&buffer[i * 4], &random_word, MIN(length, 4));
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length -= 4;
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}
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return 0;
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}
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static DEVICE_API(entropy, iproc_rng200_entropy_api) = {
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.get_entropy = iproc_rng200_driver_get_entropy,
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};
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#define IPROC_RNG200_INIT(n) \
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static const struct iproc_rng200_config iproc_rng200_##n##_cfg = { \
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DEVICE_MMIO_NAMED_ROM_INIT(base_addr, DT_DRV_INST(n)), \
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}; \
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static struct iproc_rng200_data iproc_rng200_##n##_data; \
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\
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DEVICE_DT_INST_DEFINE(n, iproc_rng200_driver_init, NULL, &iproc_rng200_##n##_data, \
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&iproc_rng200_##n##_cfg, PRE_KERNEL_1, CONFIG_ENTROPY_INIT_PRIORITY, \
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&iproc_rng200_entropy_api);
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DT_INST_FOREACH_STATUS_OKAY(IPROC_RNG200_INIT)

‎dts/arm64/broadcom/bcm2712.dtsi

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status = "okay";
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};
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rng: rng@107d208000 {
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compatible = "brcm,iproc-rng200";
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reg = <0x10 0x7d208000 0x28>;
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status = "okay";
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};
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gpio2@107d517c00 {
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compatible = "simple-bus";
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reg = <0x10 0x7d517c00 0x40>;

‎dts/bindings/rng/brcm,iproc-rng200.yaml

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# Copyright (c) 2025 TOKITA Hiroshi
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# SPDX-License-Identifier: Apache-2.0
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description: Broadcom iProc RNG200 Random Number Generator
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compatible: "brcm,iproc-rng200"
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include: base.yaml
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properties:
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reg:
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required: true

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