u-boot/drivers/rng/rockchip_rng.c
Chris Morgan 5891282bf3 rockchip: rng: add trngv1 for rk3588
This adds support for the TRNG found in the RK3588 SoC to the
rockchip_rng driver so that it can be used for things such as
seeding randomness to Linux.

Changes in V3:
 - Moved notes from commit to cover letter.
 - Added Reviewed-By tag.

Changes in V2:
 - Modified Kconfig to note that the Rockchip RNG driver supports all
   versions of the hardware (v1, v2, and the trng in the rk3588).

Signed-off-by: Lin Jinhan <troy.lin@rock-chips.com>
Signed-off-by: Chris Morgan <macromorgan@hotmail.com>
Reviewed-by: Kever Yang <kever.yang@rock-chips.com>
2023-04-21 15:16:01 +08:00

327 lines
7.9 KiB
C

// 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/bitops.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 */
/* start of TRNG V1 register define */
#define TRNG_V1_CTRL 0x0000
#define TRNG_V1_CTRL_NOP _SBF(0, 0x00)
#define TRNG_V1_CTRL_RAND _SBF(0, 0x01)
#define TRNG_V1_CTRL_SEED _SBF(0, 0x02)
#define TRNG_V1_MODE 0x0008
#define TRNG_V1_MODE_128_BIT _SBF(3, 0x00)
#define TRNG_V1_MODE_256_BIT _SBF(3, 0x01)
#define TRNG_V1_IE 0x0010
#define TRNG_V1_IE_GLBL_EN BIT(31)
#define TRNG_V1_IE_SEED_DONE_EN BIT(1)
#define TRNG_V1_IE_RAND_RDY_EN BIT(0)
#define TRNG_V1_ISTAT 0x0014
#define TRNG_V1_ISTAT_RAND_RDY BIT(0)
/* RAND0 ~ RAND7 */
#define TRNG_V1_RAND0 0x0020
#define TRNG_V1_RAND7 0x003C
#define TRNG_V1_AUTO_RQSTS 0x0060
#define TRNG_V1_VERSION 0x00F0
#define TRNG_v1_VERSION_CODE 0x46BC
/* end of TRNG V1 register define */
#define RK_RNG_TIME_OUT 50000 /* max 50ms */
#define trng_write(pdata, pos, val) writel(val, (pdata)->base + (pos))
#define trng_read(pdata, pos) readl((pdata)->base + (pos))
struct rk_rng_soc_data {
int (*rk_rng_init)(struct udevice *dev);
int (*rk_rng_read)(struct udevice *dev, void *data, size_t len);
};
struct rk_rng_plat {
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, &reg, tmp_len);
addr += sizeof(u32);
buf += tmp_len;
size -= tmp_len;
count--;
}
return 0;
}
static int rk_cryptov1_rng_read(struct udevice *dev, void *data, size_t len)
{
struct rk_rng_plat *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_cryptov2_rng_read(struct udevice *dev, void *data, size_t len)
{
struct rk_rng_plat *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 rk_trngv1_init(struct udevice *dev)
{
u32 status, version;
u32 auto_reseed_cnt = 1000;
struct rk_rng_plat *pdata = dev_get_priv(dev);
version = trng_read(pdata, TRNG_V1_VERSION);
if (version != TRNG_v1_VERSION_CODE) {
printf("wrong trng version, expected = %08x, actual = %08x",
TRNG_V1_VERSION, version);
return -EFAULT;
}
/* wait in case of RND_RDY triggered at firs power on */
readl_poll_timeout(pdata->base + TRNG_V1_ISTAT, status,
(status & TRNG_V1_ISTAT_RAND_RDY),
RK_RNG_TIME_OUT);
/* clear RAND_RDY flag for first power on */
trng_write(pdata, TRNG_V1_ISTAT, status);
/* auto reseed after (auto_reseed_cnt * 16) byte rand generate */
trng_write(pdata, TRNG_V1_AUTO_RQSTS, auto_reseed_cnt);
return 0;
}
static int rk_trngv1_rng_read(struct udevice *dev, void *data, size_t len)
{
struct rk_rng_plat *pdata = dev_get_priv(dev);
u32 reg = 0;
int retval;
if (len > RK_HW_RNG_MAX)
return -EINVAL;
trng_write(pdata, TRNG_V1_MODE, TRNG_V1_MODE_256_BIT);
trng_write(pdata, TRNG_V1_CTRL, TRNG_V1_CTRL_RAND);
retval = readl_poll_timeout(pdata->base + TRNG_V1_ISTAT, reg,
(reg & TRNG_V1_ISTAT_RAND_RDY),
RK_RNG_TIME_OUT);
/* clear ISTAT */
trng_write(pdata, TRNG_V1_ISTAT, reg);
if (retval)
goto exit;
rk_rng_read_regs(pdata->base + TRNG_V1_RAND0, data, len);
exit:
/* close TRNG */
trng_write(pdata, TRNG_V1_CTRL, TRNG_V1_CTRL_NOP);
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_plat *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_of_to_plat(struct udevice *dev)
{
struct rk_rng_plat *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_plat *pdata = dev_get_priv(dev);
int ret = 0;
pdata->soc_data = (struct rk_rng_soc_data *)dev_get_driver_data(dev);
if (pdata->soc_data->rk_rng_init)
ret = pdata->soc_data->rk_rng_init(dev);
return ret;
}
static const struct rk_rng_soc_data rk_cryptov1_soc_data = {
.rk_rng_read = rk_cryptov1_rng_read,
};
static const struct rk_rng_soc_data rk_cryptov2_soc_data = {
.rk_rng_read = rk_cryptov2_rng_read,
};
static const struct rk_rng_soc_data rk_trngv1_soc_data = {
.rk_rng_init = rk_trngv1_init,
.rk_rng_read = rk_trngv1_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_cryptov1_soc_data,
},
{
.compatible = "rockchip,cryptov2-rng",
.data = (ulong)&rk_cryptov2_soc_data,
},
{
.compatible = "rockchip,trngv1",
.data = (ulong)&rk_trngv1_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,
.of_to_plat = rockchip_rng_of_to_plat,
.priv_auto = sizeof(struct rk_rng_plat),
};