Commit f07b3e87 authored by Tomer Maimon's avatar Tomer Maimon Committed by Herbert Xu
Browse files

hwrng: npcm - Add NPCM8XX support 



Adding RNG NPCM8XX support to NPCM RNG driver.
RNG NPCM8XX uses a different clock prescaler.

As part of adding NPCM8XX support:
- Add NPCM8XX specific compatible string.
- Add data to handle architecture specific clock prescaler.

Signed-off-by: default avatarTomer Maimon <tmaimon77@gmail.com>
Signed-off-by: default avatarHerbert Xu <herbert@gondor.apana.org.au>
parent 518a198f

drivers/char/hw_random/npcm-rng.c

+10 −4
Original line number Diff line number Diff line
@@ -13,11 +13,13 @@ 
#include <linux/delay.h>

#include <linux/of_irq.h>

#include <linux/pm_runtime.h>

#include <linux/of_device.h>



#define NPCM_RNGCS_REG		0x00	/* Control and status register */

#define NPCM_RNGD_REG		0x04	/* Data register */

#define NPCM_RNGMODE_REG	0x08	/* Mode register */



#define NPCM_RNG_CLK_SET_62_5MHZ	BIT(2) /* 60-80 MHz */

#define NPCM_RNG_CLK_SET_25MHZ	GENMASK(4, 3) /* 20-25 MHz */

#define NPCM_RNG_DATA_VALID	BIT(1)

#define NPCM_RNG_ENABLE		BIT(0)
@@ -31,14 +33,14 @@ 
struct npcm_rng {

	void __iomem *base;

	struct hwrng rng;

	u32 clkp;

};



static int npcm_rng_init(struct hwrng *rng)

{

	struct npcm_rng *priv = to_npcm_rng(rng);



	writel(NPCM_RNG_CLK_SET_25MHZ | NPCM_RNG_ENABLE,

	       priv->base + NPCM_RNGCS_REG);

	writel(priv->clkp | NPCM_RNG_ENABLE, priv->base + NPCM_RNGCS_REG);



	return 0;

}
@@ -47,7 +49,7 @@ static void npcm_rng_cleanup(struct hwrng *rng) 
{

	struct npcm_rng *priv = to_npcm_rng(rng);



	writel(NPCM_RNG_CLK_SET_25MHZ, priv->base + NPCM_RNGCS_REG);

	writel(priv->clkp, priv->base + NPCM_RNGCS_REG);

}



static int npcm_rng_read(struct hwrng *rng, void *buf, size_t max, bool wait)
@@ -110,6 +112,7 @@ static int npcm_rng_probe(struct platform_device *pdev) 
	priv->rng.read = npcm_rng_read;

	priv->rng.priv = (unsigned long)&pdev->dev;

	priv->rng.quality = 1000;

	priv->clkp = (u32)(uintptr_t)of_device_get_match_data(&pdev->dev);



	writel(NPCM_RNG_M1ROSEL, priv->base + NPCM_RNGMODE_REG);
@@ -162,7 +165,10 @@ static const struct dev_pm_ops npcm_rng_pm_ops = { 
};



static const struct of_device_id rng_dt_id[] __maybe_unused = {

	{ .compatible = "nuvoton,npcm750-rng",  },

	{ .compatible = "nuvoton,npcm750-rng",

		.data = (void *)NPCM_RNG_CLK_SET_25MHZ },

	{ .compatible = "nuvoton,npcm845-rng",

		.data = (void *)NPCM_RNG_CLK_SET_62_5MHZ },

	{},

};

MODULE_DEVICE_TABLE(of, rng_dt_id);