[PATCH v3 1/4] crypto: exynos - Support Exynos5250+ SoCs

From: Åukasz Stelmach
Date: Tue Dec 12 2017 - 11:36:28 EST


Add support for PRNG in Exynos5250+ SoCs.

Signed-off-by: Åukasz Stelmach <l.stelmach@xxxxxxxxxxx>
---
.../bindings/crypto/samsung,exynos-rng4.txt | 4 +++-
drivers/crypto/exynos-rng.c | 27 ++++++++++++++++++++--
2 files changed, 28 insertions(+), 3 deletions(-)

diff --git a/Documentation/devicetree/bindings/crypto/samsung,exynos-rng4.txt b/Documentation/devicetree/bindings/crypto/samsung,exynos-rng4.txt
index 4ca8dd4d7e66..a13fbdb4bd88 100644
--- a/Documentation/devicetree/bindings/crypto/samsung,exynos-rng4.txt
+++ b/Documentation/devicetree/bindings/crypto/samsung,exynos-rng4.txt
@@ -2,7 +2,9 @@ Exynos Pseudo Random Number Generator

Required properties:

-- compatible : Should be "samsung,exynos4-rng".
+- compatible : One of:
+ - "samsung,exynos4-rng" for Exynos4210 and Exynos4412
+ - "samsung,exynos5250-prng" for Exynos5250+
- reg : Specifies base physical address and size of the registers map.
- clocks : Phandle to clock-controller plus clock-specifier pair.
- clock-names : "secss" as a clock name.
diff --git a/drivers/crypto/exynos-rng.c b/drivers/crypto/exynos-rng.c
index ed6ba796ad71..825c09619eb8 100644
--- a/drivers/crypto/exynos-rng.c
+++ b/drivers/crypto/exynos-rng.c
@@ -22,12 +22,17 @@
#include <linux/err.h>
#include <linux/io.h>
#include <linux/module.h>
+#include <linux/of_device.h>
#include <linux/platform_device.h>

#include <crypto/internal/rng.h>

#define EXYNOS_RNG_CONTROL 0x0
#define EXYNOS_RNG_STATUS 0x10
+
+#define EXYNOS_RNG_SEED_CONF 0x14
+#define EXYNOS_RNG_GEN_PRNG BIT(1)
+
#define EXYNOS_RNG_SEED_BASE 0x140
#define EXYNOS_RNG_SEED(n) (EXYNOS_RNG_SEED_BASE + (n * 0x4))
#define EXYNOS_RNG_OUT_BASE 0x160
@@ -43,6 +48,12 @@
#define EXYNOS_RNG_SEED_REGS 5
#define EXYNOS_RNG_SEED_SIZE (EXYNOS_RNG_SEED_REGS * 4)

+enum exynos_prng_type {
+ EXYNOS_PRNG_UNKNOWN = 0,
+ EXYNOS_PRNG_EXYNOS4,
+ EXYNOS_PRNG_EXYNOS5,
+};
+
/*
* Driver re-seeds itself with generated random numbers to increase
* the randomness.
@@ -63,6 +74,7 @@ struct exynos_rng_ctx {
/* Device associated memory */
struct exynos_rng_dev {
struct device *dev;
+ enum exynos_prng_type type;
void __iomem *mem;
struct clk *clk;
/* Generated numbers stored for seeding during resume */
@@ -160,8 +172,13 @@ static int exynos_rng_get_random(struct exynos_rng_dev *rng,
{
int retry = EXYNOS_RNG_WAIT_RETRIES;

- exynos_rng_writel(rng, EXYNOS_RNG_CONTROL_START,
- EXYNOS_RNG_CONTROL);
+ if (rng->type == EXYNOS_PRNG_EXYNOS4) {
+ exynos_rng_writel(rng, EXYNOS_RNG_CONTROL_START,
+ EXYNOS_RNG_CONTROL);
+ } else if (rng->type == EXYNOS_PRNG_EXYNOS5) {
+ exynos_rng_writel(rng, EXYNOS_RNG_GEN_PRNG,
+ EXYNOS_RNG_SEED_CONF);
+ }

while (!(exynos_rng_readl(rng,
EXYNOS_RNG_STATUS) & EXYNOS_RNG_STATUS_RNG_DONE) && --retry)
@@ -279,6 +296,8 @@ static int exynos_rng_probe(struct platform_device *pdev)
if (!rng)
return -ENOMEM;

+ rng->type = (enum exynos_prng_type)of_device_get_match_data(&pdev->dev);
+
rng->dev = &pdev->dev;
rng->clk = devm_clk_get(&pdev->dev, "secss");
if (IS_ERR(rng->clk)) {
@@ -367,6 +386,10 @@ static SIMPLE_DEV_PM_OPS(exynos_rng_pm_ops, exynos_rng_suspend,
static const struct of_device_id exynos_rng_dt_match[] = {
{
.compatible = "samsung,exynos4-rng",
+ .data = (const void *)EXYNOS_PRNG_EXYNOS4,
+ }, {
+ .compatible = "samsung,exynos5250-prng",
+ .data = (const void *)EXYNOS_PRNG_EXYNOS5,
},
{ },
};
--
2.11.0