rockchip: rng: Add a driver for random number generator(rng) device
Add a driver for the rng device found on rockchip platforms.
Support rng module of crypto v1 and crypto v2.
Signed-off-by: Lin Jinhan <troy.lin@rock-chips.com>
Tested-by: Peter Robinson <pbrobinson@gmail.com>
Reviewed-by: Kever Yang <kever.yang@rock-chips.com>
diff --git a/drivers/rng/Kconfig b/drivers/rng/Kconfig
index edb6152..e4b22d7 100644
--- a/drivers/rng/Kconfig
+++ b/drivers/rng/Kconfig
@@ -31,4 +31,12 @@
help
Enable STM32MP1 rng driver.
+config RNG_ROCKCHIP
+ bool "Enable random number generator for rockchip crypto rng"
+ depends on ARCH_ROCKCHIP && DM_RNG
+ default n
+ help
+ Enable random number generator for rockchip.This driver is
+ support rng module of crypto v1 and crypto v2.
+
endif
diff --git a/drivers/rng/Makefile b/drivers/rng/Makefile
index 6a8a667..44a0003 100644
--- a/drivers/rng/Makefile
+++ b/drivers/rng/Makefile
@@ -7,3 +7,4 @@
obj-$(CONFIG_RNG_MESON) += meson-rng.o
obj-$(CONFIG_RNG_SANDBOX) += sandbox_rng.o
obj-$(CONFIG_RNG_STM32MP1) += stm32mp1_rng.o
+obj-$(CONFIG_RNG_ROCKCHIP) += rockchip_rng.o
diff --git a/drivers/rng/rockchip_rng.c b/drivers/rng/rockchip_rng.c
new file mode 100644
index 0000000..47fb140
--- /dev/null
+++ b/drivers/rng/rockchip_rng.c
@@ -0,0 +1,224 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2020 Fuzhou Rockchip Electronics Co., Ltd
+ */
+#include <asm/arch-rockchip/hardware.h>
+#include <asm/io.h>
+#include <common.h>
+#include <dm.h>
+#include <linux/iopoll.h>
+#include <linux/string.h>
+#include <rng.h>
+
+#define RK_HW_RNG_MAX 32
+
+#define _SBF(s, v) ((v) << (s))
+
+/* start of CRYPTO V1 register define */
+#define CRYPTO_V1_CTRL 0x0008
+#define CRYPTO_V1_RNG_START BIT(8)
+#define CRYPTO_V1_RNG_FLUSH BIT(9)
+
+#define CRYPTO_V1_TRNG_CTRL 0x0200
+#define CRYPTO_V1_OSC_ENABLE BIT(16)
+#define CRYPTO_V1_TRNG_SAMPLE_PERIOD(x) (x)
+
+#define CRYPTO_V1_TRNG_DOUT_0 0x0204
+/* end of CRYPTO V1 register define */
+
+/* start of CRYPTO V2 register define */
+#define CRYPTO_V2_RNG_CTL 0x0400
+#define CRYPTO_V2_RNG_64_BIT_LEN _SBF(4, 0x00)
+#define CRYPTO_V2_RNG_128_BIT_LEN _SBF(4, 0x01)
+#define CRYPTO_V2_RNG_192_BIT_LEN _SBF(4, 0x02)
+#define CRYPTO_V2_RNG_256_BIT_LEN _SBF(4, 0x03)
+#define CRYPTO_V2_RNG_FATESY_SOC_RING _SBF(2, 0x00)
+#define CRYPTO_V2_RNG_SLOWER_SOC_RING_0 _SBF(2, 0x01)
+#define CRYPTO_V2_RNG_SLOWER_SOC_RING_1 _SBF(2, 0x02)
+#define CRYPTO_V2_RNG_SLOWEST_SOC_RING _SBF(2, 0x03)
+#define CRYPTO_V2_RNG_ENABLE BIT(1)
+#define CRYPTO_V2_RNG_START BIT(0)
+#define CRYPTO_V2_RNG_SAMPLE_CNT 0x0404
+#define CRYPTO_V2_RNG_DOUT_0 0x0410
+/* end of CRYPTO V2 register define */
+
+#define RK_RNG_TIME_OUT 50000 /* max 50ms */
+
+struct rk_rng_soc_data {
+ int (*rk_rng_read)(struct udevice *dev, void *data, size_t len);
+};
+
+struct rk_rng_platdata {
+ fdt_addr_t base;
+ struct rk_rng_soc_data *soc_data;
+};
+
+static int rk_rng_read_regs(fdt_addr_t addr, void *buf, size_t size)
+{
+ u32 count = RK_HW_RNG_MAX / sizeof(u32);
+ u32 reg, tmp_len;
+
+ if (size > RK_HW_RNG_MAX)
+ return -EINVAL;
+
+ while (size && count) {
+ reg = readl(addr);
+ tmp_len = min(size, sizeof(u32));
+ memcpy(buf, ®, tmp_len);
+ addr += sizeof(u32);
+ buf += tmp_len;
+ size -= tmp_len;
+ count--;
+ }
+
+ return 0;
+}
+
+static int rk_v1_rng_read(struct udevice *dev, void *data, size_t len)
+{
+ struct rk_rng_platdata *pdata = dev_get_priv(dev);
+ u32 reg = 0;
+ int retval;
+
+ if (len > RK_HW_RNG_MAX)
+ return -EINVAL;
+
+ /* enable osc_ring to get entropy, sample period is set as 100 */
+ writel(CRYPTO_V1_OSC_ENABLE | CRYPTO_V1_TRNG_SAMPLE_PERIOD(100),
+ pdata->base + CRYPTO_V1_TRNG_CTRL);
+
+ rk_clrsetreg(pdata->base + CRYPTO_V1_CTRL, CRYPTO_V1_RNG_START,
+ CRYPTO_V1_RNG_START);
+
+ retval = readl_poll_timeout(pdata->base + CRYPTO_V1_CTRL, reg,
+ !(reg & CRYPTO_V1_RNG_START),
+ RK_RNG_TIME_OUT);
+ if (retval)
+ goto exit;
+
+ rk_rng_read_regs(pdata->base + CRYPTO_V1_TRNG_DOUT_0, data, len);
+
+exit:
+ /* close TRNG */
+ rk_clrreg(pdata->base + CRYPTO_V1_CTRL, CRYPTO_V1_RNG_START);
+
+ return 0;
+}
+
+static int rk_v2_rng_read(struct udevice *dev, void *data, size_t len)
+{
+ struct rk_rng_platdata *pdata = dev_get_priv(dev);
+ u32 reg = 0;
+ int retval;
+
+ if (len > RK_HW_RNG_MAX)
+ return -EINVAL;
+
+ /* enable osc_ring to get entropy, sample period is set as 100 */
+ writel(100, pdata->base + CRYPTO_V2_RNG_SAMPLE_CNT);
+
+ reg |= CRYPTO_V2_RNG_256_BIT_LEN;
+ reg |= CRYPTO_V2_RNG_SLOWER_SOC_RING_0;
+ reg |= CRYPTO_V2_RNG_ENABLE;
+ reg |= CRYPTO_V2_RNG_START;
+
+ rk_clrsetreg(pdata->base + CRYPTO_V2_RNG_CTL, 0xffff, reg);
+
+ retval = readl_poll_timeout(pdata->base + CRYPTO_V2_RNG_CTL, reg,
+ !(reg & CRYPTO_V2_RNG_START),
+ RK_RNG_TIME_OUT);
+ if (retval)
+ goto exit;
+
+ rk_rng_read_regs(pdata->base + CRYPTO_V2_RNG_DOUT_0, data, len);
+
+exit:
+ /* close TRNG */
+ rk_clrreg(pdata->base + CRYPTO_V2_RNG_CTL, 0xffff);
+
+ return retval;
+}
+
+static int rockchip_rng_read(struct udevice *dev, void *data, size_t len)
+{
+ unsigned char *buf = data;
+ unsigned int i;
+ int ret = -EIO;
+
+ struct rk_rng_platdata *pdata = dev_get_priv(dev);
+
+ if (!len)
+ return 0;
+
+ if (!pdata->soc_data || !pdata->soc_data->rk_rng_read)
+ return -EINVAL;
+
+ for (i = 0; i < len / RK_HW_RNG_MAX; i++, buf += RK_HW_RNG_MAX) {
+ ret = pdata->soc_data->rk_rng_read(dev, buf, RK_HW_RNG_MAX);
+ if (ret)
+ goto exit;
+ }
+
+ if (len % RK_HW_RNG_MAX)
+ ret = pdata->soc_data->rk_rng_read(dev, buf,
+ len % RK_HW_RNG_MAX);
+
+exit:
+ return ret;
+}
+
+static int rockchip_rng_ofdata_to_platdata(struct udevice *dev)
+{
+ struct rk_rng_platdata *pdata = dev_get_priv(dev);
+
+ memset(pdata, 0x00, sizeof(*pdata));
+
+ pdata->base = (fdt_addr_t)dev_read_addr_ptr(dev);
+ if (!pdata->base)
+ return -ENOMEM;
+
+ return 0;
+}
+
+static int rockchip_rng_probe(struct udevice *dev)
+{
+ struct rk_rng_platdata *pdata = dev_get_priv(dev);
+
+ pdata->soc_data = (struct rk_rng_soc_data *)dev_get_driver_data(dev);
+
+ return 0;
+}
+
+static const struct rk_rng_soc_data rk_rng_v1_soc_data = {
+ .rk_rng_read = rk_v1_rng_read,
+};
+
+static const struct rk_rng_soc_data rk_rng_v2_soc_data = {
+ .rk_rng_read = rk_v2_rng_read,
+};
+
+static const struct dm_rng_ops rockchip_rng_ops = {
+ .read = rockchip_rng_read,
+};
+
+static const struct udevice_id rockchip_rng_match[] = {
+ {
+ .compatible = "rockchip,cryptov1-rng",
+ .data = (ulong)&rk_rng_v1_soc_data,
+ },
+ {
+ .compatible = "rockchip,cryptov2-rng",
+ .data = (ulong)&rk_rng_v2_soc_data,
+ },
+ {},
+};
+
+U_BOOT_DRIVER(rockchip_rng) = {
+ .name = "rockchip-rng",
+ .id = UCLASS_RNG,
+ .of_match = rockchip_rng_match,
+ .ops = &rockchip_rng_ops,
+ .probe = rockchip_rng_probe,
+ .ofdata_to_platdata = rockchip_rng_ofdata_to_platdata,
+ .priv_auto_alloc_size = sizeof(struct rk_rng_platdata),
+};