On 14.12.20 17:24, matthias.bgg@kernel.org wrote:
From: Matthias Brugger mbrugger@suse.com
Add support for random number generator RNG200. This is for example found on RPi4.
Signed-off-by: Matthias Brugger mbrugger@suse.com
drivers/rng/Kconfig | 6 ++ drivers/rng/Makefile | 1 + drivers/rng/iproc_rng200.c | 186 +++++++++++++++++++++++++++++++++++++ 3 files changed, 193 insertions(+) create mode 100644 drivers/rng/iproc_rng200.c
diff --git a/drivers/rng/Kconfig b/drivers/rng/Kconfig index 11001c8ae7..94915d45b3 100644 --- a/drivers/rng/Kconfig +++ b/drivers/rng/Kconfig @@ -46,4 +46,10 @@ config RNG_ROCKCHIP Enable random number generator for rockchip.This driver is support rng module of crypto v1 and crypto v2.
+config RNG_IPROC200
- bool "Broadcom iProc RNG200 random number generator"
- depends on DM_RNG
Should this depend on CONFIG_ARCH_BCM283X too?
Best regards
Heinrich
- default n
- help
Enable random number generator for RPI4.endif diff --git a/drivers/rng/Makefile b/drivers/rng/Makefile index 8953406882..39f7ee3f03 100644 --- a/drivers/rng/Makefile +++ b/drivers/rng/Makefile @@ -9,3 +9,4 @@ obj-$(CONFIG_RNG_SANDBOX) += sandbox_rng.o obj-$(CONFIG_RNG_MSM) += msm_rng.o obj-$(CONFIG_RNG_STM32MP1) += stm32mp1_rng.o obj-$(CONFIG_RNG_ROCKCHIP) += rockchip_rng.o +obj-$(CONFIG_RNG_IPROC200) += iproc_rng200.o diff --git a/drivers/rng/iproc_rng200.c b/drivers/rng/iproc_rng200.c new file mode 100644 index 0000000000..1063f43953 --- /dev/null +++ b/drivers/rng/iproc_rng200.c @@ -0,0 +1,186 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/*
- Copyright 2020, Matthias Brugger mbrugger@suse.com
- Driver for Raspberry Pi hardware random number generator
- */
+#include <common.h> +#include <dm.h> +#include <linux/delay.h> +#include <rng.h> +#include <asm/io.h>
+#define usleep_range(a, b) udelay((b))
+#define RNG_CTRL_OFFSET 0x00 +#define RNG_CTRL_RNG_RBGEN_MASK 0x00001FFF +#define RNG_CTRL_RNG_RBGEN_ENABLE 0x00000001 +#define RNG_CTRL_RNG_RBGEN_DISABLE 0x00000000
+#define RNG_SOFT_RESET_OFFSET 0x04 +#define RNG_SOFT_RESET 0x00000001
+#define RBG_SOFT_RESET_OFFSET 0x08 +#define RBG_SOFT_RESET 0x00000001
+#define RNG_INT_STATUS_OFFSET 0x18 +#define RNG_INT_STATUS_MASTER_FAIL_LOCKOUT_IRQ_MASK 0x80000000 +#define RNG_INT_STATUS_NIST_FAIL_IRQ_MASK 0x00000020
+#define RNG_FIFO_DATA_OFFSET 0x20
+#define RNG_FIFO_COUNT_OFFSET 0x24 +#define RNG_FIFO_COUNT_RNG_FIFO_COUNT_MASK 0x000000FF
+struct iproc_rng200_platdata {
- fdt_addr_t base;
+};
+static void iproc_rng200_enable(struct iproc_rng200_platdata *pdata, bool enable) +{
- fdt_addr_t rng_base = pdata->base;
- u32 val;
- val = readl(rng_base + RNG_CTRL_OFFSET);
- val &= ~RNG_CTRL_RNG_RBGEN_MASK;
- if (enable)
val |= RNG_CTRL_RNG_RBGEN_ENABLE;- else
val &= ~RNG_CTRL_RNG_RBGEN_ENABLE;- writel(val, rng_base + RNG_CTRL_OFFSET);
+}
+static void iproc_rng200_restart(struct iproc_rng200_platdata *pdata) +{
- fdt_addr_t rng_base = pdata->base;
- u32 val;
- iproc_rng200_enable(pdata, false);
- /* Clear all interrupt status */
- writel(0xFFFFFFFFUL, rng_base + RNG_INT_STATUS_OFFSET);
- /* Reset RNG and RBG */
- val = readl(rng_base + RBG_SOFT_RESET_OFFSET);
- val |= RBG_SOFT_RESET;
- writel(val, rng_base + RBG_SOFT_RESET_OFFSET);
- val = readl(rng_base + RNG_SOFT_RESET_OFFSET);
- val |= RNG_SOFT_RESET;
- writel(val, rng_base + RNG_SOFT_RESET_OFFSET);
- val = readl(rng_base + RNG_SOFT_RESET_OFFSET);
- val &= ~RNG_SOFT_RESET;
- writel(val, rng_base + RNG_SOFT_RESET_OFFSET);
- val = readl(rng_base + RBG_SOFT_RESET_OFFSET);
- val &= ~RBG_SOFT_RESET;
- writel(val, rng_base + RBG_SOFT_RESET_OFFSET);
- iproc_rng200_enable(pdata, true);
+}
+static int iproc_rng200_read(struct udevice *dev, void *data, size_t len) +{
- struct iproc_rng200_platdata *priv = dev_get_platdata(dev);
- char *buf = (char *)data;
- u32 num_remaining = len;
- u32 status;
- #define MAX_RESETS_PER_READ 1
- u32 num_resets = 0;
- while (num_remaining > 0) {
/* Is RNG sane? If not, reset it. */status = readl(priv->base + RNG_INT_STATUS_OFFSET);if ((status & (RNG_INT_STATUS_MASTER_FAIL_LOCKOUT_IRQ_MASK |RNG_INT_STATUS_NIST_FAIL_IRQ_MASK)) != 0) {if (num_resets >= MAX_RESETS_PER_READ)return len - num_remaining;iproc_rng200_restart(priv);num_resets++;}/* Are there any random numbers available? */if ((readl(priv->base + RNG_FIFO_COUNT_OFFSET) &RNG_FIFO_COUNT_RNG_FIFO_COUNT_MASK) > 0) {if (num_remaining >= sizeof(u32)) {/* Buffer has room to store entire word */*(u32 *)buf = readl(priv->base +RNG_FIFO_DATA_OFFSET);buf += sizeof(u32);num_remaining -= sizeof(u32);} else {/* Buffer can only store partial word */u32 rnd_number = readl(priv->base +RNG_FIFO_DATA_OFFSET);memcpy(buf, &rnd_number, num_remaining);buf += num_remaining;num_remaining = 0;}} else {/* Can wait, give others chance to run */usleep_range(min(num_remaining * 10, 500U), 500);}- }
- return 0;
+}
+static int iproc_rng200_probe(struct udevice *dev) +{
- struct iproc_rng200_platdata *priv = dev_get_platdata(dev);
- iproc_rng200_enable(priv, true);
- return 0;
+}
+static int iproc_rng200_remove(struct udevice *dev) +{
- struct iproc_rng200_platdata *priv = dev_get_platdata(dev);
- iproc_rng200_enable(priv, false);
- return 0;
+}
+static int iproc_rng200_ofdata_to_platdata(struct udevice *dev) +{
- struct iproc_rng200_platdata *pdata = dev_get_platdata(dev);
- pdata->base = dev_read_addr(dev);
- if (!pdata->base)
return -ENODEV;- return 0;
+}
+static const struct dm_rng_ops iproc_rng200_ops = {
- .read = iproc_rng200_read,
+};
+static const struct udevice_id iproc_rng200_rng_match[] = {
- { .compatible = "brcm,bcm2711-rng200", },
- { .compatible = "brcm,iproc-rng200", },
- {},
+};
+U_BOOT_DRIVER(iproc_rng200_rng) = {
- .name = "iproc_rng200-rng",
- .id = UCLASS_RNG,
- .of_match = iproc_rng200_rng_match,
- .ops = &iproc_rng200_ops,
- .probe = iproc_rng200_probe,
- .remove = iproc_rng200_remove,
- .platdata_auto_alloc_size = sizeof(struct iproc_rng200_platdata),
- .ofdata_to_platdata = iproc_rng200_ofdata_to_platdata,
+};