hwrng: hisi - remove HiSilicon TRNG driver

Driver of HiSilicon true random number generator(TRNG)
is removed from 'drivers/char/hw_random'.

Both 'Kunpeng 920' and 'Kunpeng 930' chips have TRNG,
however, PRNG is only supported by 'Kunpeng 930'.
So, this driver is moved to 'drivers/crypto/hisilicon/trng/'
in the next to enable the two's TRNG better.
Signed-off-by: Weili Qian <qianweili@huawei.com>
Reviewed-by: Zaibo Xu <xuzaibo@huawei.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

drivers/char/hw_random/Kconfig

@@ -348,19 +348,6 @@ config HW_RANDOM_HISI
 
 	  If unsure, say Y.
 
-config HW_RANDOM_HISI_V2
-	tristate "HiSilicon True Random Number Generator V2 support"
-	depends on HW_RANDOM && ARM64 && ACPI
-	default HW_RANDOM
-	help
-	  This driver provides kernel-side support for the True Random Number
-	  Generator V2 hardware found on HiSilicon Hi1620 SoC.
-
-	  To compile this driver as a module, choose M here: the
-	  module will be called hisi-trng-v2.
-
-	  If unsure, say Y.
-
 config HW_RANDOM_ST
 	tristate "ST Microelectronics HW Random Number Generator support"
 	depends on HW_RANDOM && ARCH_STI

drivers/char/hw_random/Makefile

@@ -30,7 +30,6 @@ obj-$(CONFIG_HW_RANDOM_NOMADIK) += nomadik-rng.o
 obj-$(CONFIG_HW_RANDOM_PSERIES) += pseries-rng.o
 obj-$(CONFIG_HW_RANDOM_POWERNV) += powernv-rng.o
 obj-$(CONFIG_HW_RANDOM_HISI)	+= hisi-rng.o
-obj-$(CONFIG_HW_RANDOM_HISI_V2) += hisi-trng-v2.o
 obj-$(CONFIG_HW_RANDOM_BCM2835) += bcm2835-rng.o
 obj-$(CONFIG_HW_RANDOM_IPROC_RNG200) += iproc-rng200.o
 obj-$(CONFIG_HW_RANDOM_ST) += st-rng.o

drivers/char/hw_random/hisi-trng-v2.c

-// SPDX-License-Identifier: GPL-2.0
-/* Copyright (c) 2019 HiSilicon Limited. */
-
-#include <linux/acpi.h>
-#include <linux/err.h>
-#include <linux/hw_random.h>
-#include <linux/io.h>
-#include <linux/iopoll.h>
-#include <linux/kernel.h>
-#include <linux/module.h>
-#include <linux/platform_device.h>
-#include <linux/random.h>
-
-#define HISI_TRNG_REG		0x00F0
-#define HISI_TRNG_BYTES		4
-#define HISI_TRNG_QUALITY	512
-#define SLEEP_US		10
-#define TIMEOUT_US		10000
-
-struct hisi_trng {
-	void __iomem *base;
-	struct hwrng rng;
-};
-
-static int hisi_trng_read(struct hwrng *rng, void *buf, size_t max, bool wait)
-{
-	struct hisi_trng *trng;
-	int currsize = 0;
-	u32 val = 0;
-	u32 ret;
-
-	trng = container_of(rng, struct hisi_trng, rng);
-
-	do {
-		ret = readl_poll_timeout(trng->base + HISI_TRNG_REG, val,
-					 val, SLEEP_US, TIMEOUT_US);
-		if (ret)
-			return currsize;
-
-		if (max - currsize >= HISI_TRNG_BYTES) {
-			memcpy(buf + currsize, &val, HISI_TRNG_BYTES);
-			currsize += HISI_TRNG_BYTES;
-			if (currsize == max)
-				return currsize;
-			continue;
-		}
-
-		/* copy remaining bytes */
-		memcpy(buf + currsize, &val, max - currsize);
-		currsize = max;
-	} while (currsize < max);
-
-	return currsize;
-}
-
-static int hisi_trng_probe(struct platform_device *pdev)
-{
-	struct hisi_trng *trng;
-	int ret;
-
-	trng = devm_kzalloc(&pdev->dev, sizeof(*trng), GFP_KERNEL);
-	if (!trng)
-		return -ENOMEM;
-
-	trng->base = devm_platform_ioremap_resource(pdev, 0);
-	if (IS_ERR(trng->base))
-		return PTR_ERR(trng->base);
-
-	trng->rng.name = pdev->name;
-	trng->rng.read = hisi_trng_read;
-	trng->rng.quality = HISI_TRNG_QUALITY;
-
-	ret = devm_hwrng_register(&pdev->dev, &trng->rng);
-	if (ret)
-		dev_err(&pdev->dev, "failed to register hwrng!\n");
-
-	return ret;
-}
-
-static const struct acpi_device_id hisi_trng_acpi_match[] = {
-	{ "HISI02B3", 0 },
-	{ }
-};
-MODULE_DEVICE_TABLE(acpi, hisi_trng_acpi_match);
-
-static struct platform_driver hisi_trng_driver = {
-	.probe		= hisi_trng_probe,
-	.driver		= {
-		.name	= "hisi-trng-v2",
-		.acpi_match_table = ACPI_PTR(hisi_trng_acpi_match),
-	},
-};
-
-module_platform_driver(hisi_trng_driver);
-
-MODULE_LICENSE("GPL v2");
-MODULE_AUTHOR("Weili Qian <qianweili@huawei.com>");
-MODULE_AUTHOR("Zaibo Xu <xuzaibo@huawei.com>");
-MODULE_DESCRIPTION("HiSilicon true random number generator V2 driver");