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

[Krzysztof Kozlowski]

On Tue, Dec 12, 2017 at 5:36 PM, Łukasz Stelmach  wrote:
> Add support for PRNG in Exynos5250+ SoCs.
>
> Signed-off-by: Łukasz Stelmach 
> ---
>  .../bindings/crypto/samsung,exynos-rng4.txt|  4 +++-
>  drivers/crypto/exynos-rng.c| 27 
> --
>  2 files changed, 28 insertions(+), 3 deletions(-)

Reviewed-by: Krzysztof Kozlowski 

Best regards,
Krzysztof

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

[Łukasz Stelmach]

Add support for PRNG in Exynos5250+ SoCs.

Signed-off-by: Łukasz Stelmach 
---
 .../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 
 #include 
 #include 
+#include 
 #include 
 
 #include 
 
 #define EXYNOS_RNG_CONTROL 0x0
 #define EXYNOS_RNG_STATUS  0x10
+
+#define EXYNOS_RNG_SEED_CONF   0x14
+#define EXYNOS_RNG_GEN_PRNGBIT(1)
+
 #define EXYNOS_RNG_SEED_BASE   0x140
 #define EXYNOS_RNG_SEED(n) (EXYNOS_RNG_SEED_BASE + (n * 0x4))
 #define EXYNOS_RNG_OUT_BASE0x160
@@ -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(>dev);
+
rng->dev = >dev;
rng->clk = devm_clk_get(>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