[HIFN]: Add support for using the random number generator (fcd06755) · Commits · e / devices / android_kernel_oneplus_sm8150

drivers/crypto/hifn_795x.c

+81 −1

Original line number	Diff line number	Diff line
		@@ -31,6 +31,8 @@
		#include <linux/highmem.h>
		#include <linux/interrupt.h>
		#include <linux/crypto.h>
		#include <linux/hw_random.h>
		#include <linux/ktime.h>

		#include <crypto/algapi.h>
		#include <crypto/des.h>
		@@ -458,6 +460,14 @@ struct hifn_device

		struct crypto_queue queue;
		struct list_head alg_list;

		unsigned int pk_clk_freq;

		#if defined(CONFIG_HW_RANDOM) \|\| defined(CONFIG_HW_RANDOM_MODULE)
		unsigned int rng_wait_time;
		ktime_t rngtime;
		struct hwrng rng;
		#endif
		};

		#define HIFN_D_LENGTH 0x0000ffff
		@@ -785,6 +795,56 @@ static struct pci2id {
		}
		};

		#if defined(CONFIG_HW_RANDOM) \|\| defined(CONFIG_HW_RANDOM_MODULE)
		static int hifn_rng_data_present(struct hwrng *rng, int wait)
		{
		struct hifn_device dev = (struct hifn_device )rng->priv;
		s64 nsec;

		nsec = ktime_to_ns(ktime_sub(ktime_get(), dev->rngtime));
		nsec -= dev->rng_wait_time;
		if (nsec <= 0)
		return 1;
		if (!wait)
		return 0;
		ndelay(nsec);
		return 1;
		}

		static int hifn_rng_data_read(struct hwrng rng, u32 data)
		{
		struct hifn_device dev = (struct hifn_device )rng->priv;

		*data = hifn_read_1(dev, HIFN_1_RNG_DATA);
		dev->rngtime = ktime_get();
		return 4;
		}

		static int hifn_register_rng(struct hifn_device *dev)
		{
		/*
		* We must wait at least 256 Pk_clk cycles between two reads of the rng.
		*/
		dev->rng_wait_time = DIV_ROUND_UP(NSEC_PER_SEC, dev->pk_clk_freq) *
		256;

		dev->rng.name = dev->name;
		dev->rng.data_present = hifn_rng_data_present,
		dev->rng.data_read = hifn_rng_data_read,
		dev->rng.priv = (unsigned long)dev;

		return hwrng_register(&dev->rng);
		}

		static void hifn_unregister_rng(struct hifn_device *dev)
		{
		hwrng_unregister(&dev->rng);
		}
		#else
		#define hifn_register_rng(dev) 0
		#define hifn_unregister_rng(dev)
		#endif

		static int hifn_init_pubrng(struct hifn_device *dev)
		{
		int i;
		@@ -820,6 +880,11 @@ static int hifn_init_pubrng(struct hifn_device *dev)
		dprintk("Chip %s: RNG engine has been successfully initialised.\n",
		dev->name);

		#if defined(CONFIG_HW_RANDOM) \|\| defined(CONFIG_HW_RANDOM_MODULE)
		/* First value must be discarded */
		hifn_read_1(dev, HIFN_1_RNG_DATA);
		dev->rngtime = ktime_get();
		#endif
		return 0;
		}

		@@ -952,6 +1017,14 @@ static void hifn_init_pll(struct hifn_device *dev)
		/* Switch the engines to the PLL */
		hifn_write_1(dev, HIFN_1_PLL, pllcfg \|
		HIFN_PLL_PK_CLK_PLL \| HIFN_PLL_PE_CLK_PLL);

		/*
		* The Fpk_clk runs at half the total speed. Its frequency is needed to
		* calculate the minimum time between two reads of the rng. Since 33MHz
		* is actually 33.333... we overestimate the frequency here, resulting
		* in slightly larger intervals.
		*/
		dev->pk_clk_freq = 1000000 * (freq + 1) * m / 2;
		}

		static void hifn_init_registers(struct hifn_device *dev)
		@@ -2609,10 +2682,14 @@ static int hifn_probe(struct pci_dev pdev, const struct pci_device_id id)
		if (err)
		goto err_out_stop_device;

		err = hifn_register_alg(dev);
		err = hifn_register_rng(dev);
		if (err)
		goto err_out_stop_device;

		err = hifn_register_alg(dev);
		if (err)
		goto err_out_unregister_rng;

		INIT_DELAYED_WORK(&dev->work, hifn_work);
		schedule_delayed_work(&dev->work, HZ);

		@@ -2622,6 +2699,8 @@ static int hifn_probe(struct pci_dev pdev, const struct pci_device_id id)

		return 0;

		err_out_unregister_rng:
		hifn_unregister_rng(dev);
		err_out_stop_device:
		hifn_reset_dma(dev, 1);
		hifn_stop_device(dev);
		@@ -2662,6 +2741,7 @@ static void hifn_remove(struct pci_dev *pdev)
		cancel_delayed_work(&dev->work);
		flush_scheduled_work();

		hifn_unregister_rng(dev);
		hifn_unregister_alg(dev);
		hifn_reset_dma(dev, 1);
		hifn_stop_device(dev);