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>
This commit is contained in:
TOKITA Hiroshi 2025-05-02 14:12:21 +09:00 committed by Benjamin Cabé
commit 431f202732
7 changed files with 183 additions and 0 deletions

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@ -24,6 +24,7 @@
zephyr,console = &uart10;
zephyr,shell-uart = &uart10;
zephyr,pcie-controller = &pcie1;
zephyr,entropy = &rng;
};
leds {

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@ -16,6 +16,7 @@ endif()
zephyr_library_sources_ifdef(CONFIG_USERSPACE entropy_handlers.c)
# zephyr-keep-sorted-start
zephyr_library_sources_ifdef(CONFIG_ENTROPY_BRCM_IPROC_RNG200 entropy_iproc_rng200.c)
zephyr_library_sources_ifdef(CONFIG_ENTROPY_BT_HCI entropy_bt_hci.c)
zephyr_library_sources_ifdef(CONFIG_ENTROPY_CC13XX_CC26XX_RNG entropy_cc13xx_cc26xx.c)
zephyr_library_sources_ifdef(CONFIG_ENTROPY_ESP32_RNG entropy_esp32.c)

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

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@ -0,0 +1,10 @@
# Copyright (c) 2025 TOKITA Hiroshi
# SPDX-License-Identifier: Apache-2.0
config ENTROPY_BRCM_IPROC_RNG200
bool "Broadcom iProc RNG200 driver"
default y
depends on DT_HAS_BRCM_IPROC_RNG200_ENABLED
select ENTROPY_HAS_DRIVER
help
Enable the Broadcom iProc RNG200 random number generator

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@ -0,0 +1,152 @@
/*
* Copyright (c) 2025 TOKITA Hiroshi
*
* SPDX-License-Identifier: Apache-2.0
*/
#define DT_DRV_COMPAT brcm_iproc_rng200
#include <zephyr/logging/log.h>
LOG_MODULE_REGISTER(iproc_rng200_entropy, CONFIG_ENTROPY_LOG_LEVEL);
#include <zephyr/device.h>
#include <zephyr/drivers/entropy.h>
#include <errno.h>
#include <zephyr/init.h>
#include <zephyr/kernel.h>
#define IPROC_RNG200_CTRL_OFFS 0x00
#define IPROC_RNG200_RNG_RESET_OFFS 0x04
#define IPROC_RNG200_RBG_RESET_OFFS 0x08
#define IPROC_RNG200_RESERVED1_OFFS 0x0c
#define IPROC_RNG200_RESERVED2_OFFS 0x10
#define IPROC_RNG200_RESERVED3_OFFS 0x14
#define IPROC_RNG200_INT_STATUS_OFFS 0x18
#define IPROC_RNG200_RESERVED4_OFFS 0x1c
#define IPROC_RNG200_FIFO_DATA_OFFS 0x20
#define IPROC_RNG200_FIFO_COUNT_OFFS 0x24
#define IPROC_RNG200_CTRL_RBG_EN BIT(0)
#define IPROC_RNG200_RESET_EN BIT(0)
#define IPROC_RNG200_INT_STATUS_NIST_FAIL BIT(5)
#define IPROC_RNG200_INT_STATUS_MASTER_FAIL_LOCKOUT BIT(31)
#define IPROC_RNG200_CTRL_RBG_EN_MASK BIT_MASK(13)
#define IPROC_RNG200_FIFO_COUNT_MASK BIT_MASK(8)
/* time needed to fill fifo when empty */
#define IPROC_RNG200_FIFO_REFILL_TIME_USEC 40
#define IPROC_RNG200_FIFO_REFILL_MAX_RETRIES 5
#define DEV_CFG(dev) ((const struct iproc_rng200_config *)(dev)->config)
#define DEV_DATA(dev) ((struct iproc_rng200_data *)(dev)->data)
struct iproc_rng200_config {
DEVICE_MMIO_NAMED_ROM(base_addr);
};
struct iproc_rng200_data {
DEVICE_MMIO_NAMED_RAM(base_addr);
struct k_mutex mutex;
};
static int iproc_rng200_driver_init(const struct device *dev)
{
struct iproc_rng200_data *const data = dev->data;
k_mutex_init(&data->mutex);
DEVICE_MMIO_NAMED_MAP(dev, base_addr, K_MEM_CACHE_NONE);
const mem_addr_t base = DEVICE_MMIO_NAMED_GET(dev, base_addr);
const uint32_t val =
sys_read32(base + IPROC_RNG200_CTRL_OFFS) & IPROC_RNG200_CTRL_RBG_EN_MASK;
sys_write32(val & ~IPROC_RNG200_CTRL_RBG_EN, base + IPROC_RNG200_CTRL_OFFS);
return 0;
}
static int iproc_rng200_driver_get_entropy(const struct device *dev, uint8_t *buffer,
uint16_t length)
{
const mem_addr_t base = DEVICE_MMIO_NAMED_GET(dev, base_addr);
const uint32_t word_count = DIV_ROUND_UP(length, 4);
struct iproc_rng200_data *const data = dev->data;
uint32_t retries_left;
uint32_t random_word;
for (uint32_t i = 0; i < word_count; i++) {
retries_left = IPROC_RNG200_FIFO_REFILL_MAX_RETRIES;
k_mutex_lock(&data->mutex, K_FOREVER);
while (true) {
const uint32_t status = sys_read32(base + IPROC_RNG200_INT_STATUS_OFFS);
uint32_t val;
if (status & (IPROC_RNG200_INT_STATUS_MASTER_FAIL_LOCKOUT |
IPROC_RNG200_INT_STATUS_NIST_FAIL)) {
sys_write32(0xFFFFFFFF, base + IPROC_RNG200_INT_STATUS_OFFS);
val = sys_read32(base + IPROC_RNG200_RNG_RESET_OFFS);
sys_write32(val | IPROC_RNG200_RESET_EN,
base + IPROC_RNG200_RNG_RESET_OFFS);
val = sys_read32(base + IPROC_RNG200_RBG_RESET_OFFS);
sys_write32(val | IPROC_RNG200_RESET_EN,
base + IPROC_RNG200_RBG_RESET_OFFS);
val = sys_read32(base + IPROC_RNG200_RNG_RESET_OFFS);
sys_write32(val & ~IPROC_RNG200_RESET_EN,
base + IPROC_RNG200_RNG_RESET_OFFS);
val = sys_read32(base + IPROC_RNG200_RBG_RESET_OFFS);
sys_write32(val & ~IPROC_RNG200_RESET_EN,
base + IPROC_RNG200_RBG_RESET_OFFS);
}
/* make sure fifo has at least one random word */
const uint32_t fcnt = sys_read32(base + IPROC_RNG200_FIFO_COUNT_OFFS);
if ((fcnt & IPROC_RNG200_FIFO_COUNT_MASK) > 0) {
/* get new random word */
random_word = sys_read32(base + IPROC_RNG200_FIFO_DATA_OFFS);
break;
}
/* currently no random values available, thus wait */
retries_left--;
if (!retries_left) {
/* number of retries exhausted, give up */
k_mutex_unlock(&data->mutex);
return -ETIMEDOUT;
}
k_sleep(K_USEC(IPROC_RNG200_FIFO_REFILL_TIME_USEC));
}
k_mutex_unlock(&data->mutex);
memcpy(&buffer[i * 4], &random_word, MIN(length, 4));
length -= 4;
}
return 0;
}
static DEVICE_API(entropy, iproc_rng200_entropy_api) = {
.get_entropy = iproc_rng200_driver_get_entropy,
};
#define IPROC_RNG200_INIT(n) \
static const struct iproc_rng200_config iproc_rng200_##n##_cfg = { \
DEVICE_MMIO_NAMED_ROM_INIT(base_addr, DT_DRV_INST(n)), \
}; \
static struct iproc_rng200_data iproc_rng200_##n##_data; \
\
DEVICE_DT_INST_DEFINE(n, iproc_rng200_driver_init, NULL, &iproc_rng200_##n##_data, \
&iproc_rng200_##n##_cfg, PRE_KERNEL_1, CONFIG_ENTROPY_INIT_PRIORITY, \
&iproc_rng200_entropy_api);
DT_INST_FOREACH_STATUS_OKAY(IPROC_RNG200_INIT)

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@ -52,6 +52,12 @@
status = "okay";
};
rng: rng@107d208000 {
compatible = "brcm,iproc-rng200";
reg = <0x10 0x7d208000 0x28>;
status = "okay";
};
gpio2@107d517c00 {
compatible = "simple-bus";
reg = <0x10 0x7d517c00 0x40>;

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@ -0,0 +1,12 @@
# Copyright (c) 2025 TOKITA Hiroshi
# SPDX-License-Identifier: Apache-2.0
description: Broadcom iProc RNG200 Random Number Generator
compatible: "brcm,iproc-rng200"
include: base.yaml
properties:
reg:
required: true