From: Chris Morgan macromorgan@hotmail.com
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.
This code was taken wholesale from the Rockchip BSP U-Boot source located here: https://github.com/rockchip-linux/u-boot/commit/09f31aed858c36a8a5ee20789712...
Tested on an Indiedroid Nova with an RK3588s.
Signed-off-by: Lin Jinhan troy.lin@rock-chips.com Signed-off-by: Chris Morgan macromorgan@hotmail.com --- drivers/rng/rockchip_rng.c | 120 ++++++++++++++++++++++++++++++++++--- 1 file changed, 111 insertions(+), 9 deletions(-)
diff --git a/drivers/rng/rockchip_rng.c b/drivers/rng/rockchip_rng.c index 800150f114..705b424cf3 100644 --- a/drivers/rng/rockchip_rng.c +++ b/drivers/rng/rockchip_rng.c @@ -43,9 +43,41 @@ #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); };
@@ -75,7 +107,7 @@ static int rk_rng_read_regs(fdt_addr_t addr, void *buf, size_t size) return 0; }
-static int rk_v1_rng_read(struct udevice *dev, void *data, size_t len) +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; @@ -106,7 +138,7 @@ exit: return 0; }
-static int rk_v2_rng_read(struct udevice *dev, void *data, size_t len) +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; @@ -140,6 +172,63 @@ exit: 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; @@ -184,18 +273,27 @@ static int rockchip_rng_of_to_plat(struct udevice *dev) 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);
- return 0; + 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_rng_v1_soc_data = { - .rk_rng_read = rk_v1_rng_read, +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_rng_v2_soc_data = { - .rk_rng_read = rk_v2_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 = { @@ -205,11 +303,15 @@ static const struct dm_rng_ops rockchip_rng_ops = { static const struct udevice_id rockchip_rng_match[] = { { .compatible = "rockchip,cryptov1-rng", - .data = (ulong)&rk_rng_v1_soc_data, + .data = (ulong)&rk_cryptov1_soc_data, }, { .compatible = "rockchip,cryptov2-rng", - .data = (ulong)&rk_rng_v2_soc_data, + .data = (ulong)&rk_cryptov2_soc_data, + }, + { + .compatible = "rockchip,trngv1", + .data = (ulong)&rk_trngv1_soc_data, }, {}, };