[PATCH 07/10] char: hw_random: Remove tx4939 driver

Thomas Bogendoerfer
2021-01-05T14:06:17Z

CPU support for TX49xx is getting removed, so remove hw_random driver
for it.

Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
---
drivers/char/hw_random/Kconfig | 13 ---
drivers/char/hw_random/Makefile | 1 -
drivers/char/hw_random/tx4939-rng.c | 157 ----------------------------
3 files changed, 171 deletions(-)
delete mode 100644 drivers/char/hw_random/tx4939-rng.c

diff --git a/drivers/char/hw_random/Kconfig b/drivers/char/hw_random/Kconfig
index 1fe006f3f12f..9d13d640384a 100644
--- a/drivers/char/hw_random/Kconfig
+++ b/drivers/char/hw_random/Kconfig
@@ -226,19 +226,6 @@ config HW_RANDOM_VIRTIO
To compile this driver as a module, choose M here: the
module will be called virtio-rng. If unsure, say N.

-config HW_RANDOM_TX4939
- tristate "TX4939 Random Number Generator support"
- depends on SOC_TX4939
- default HW_RANDOM
- help
- This driver provides kernel-side support for the Random Number
- Generator hardware found on TX4939 SoC.
-
- To compile this driver as a module, choose M here: the
- module will be called tx4939-rng.
-
- If unsure, say Y.
-
config HW_RANDOM_MXC_RNGA
tristate "Freescale i.MX RNGA Random Number Generator"
depends on SOC_IMX31
diff --git a/drivers/char/hw_random/Makefile b/drivers/char/hw_random/Makefile
index 8933fada74f2..b2aa37162e24 100644
--- a/drivers/char/hw_random/Makefile
+++ b/drivers/char/hw_random/Makefile
@@ -20,7 +20,6 @@ obj-$(CONFIG_HW_RANDOM_OMAP) += omap-rng.o
obj-$(CONFIG_HW_RANDOM_OMAP3_ROM) += omap3-rom-rng.o
obj-$(CONFIG_HW_RANDOM_PASEMI) += pasemi-rng.o
obj-$(CONFIG_HW_RANDOM_VIRTIO) += virtio-rng.o
-obj-$(CONFIG_HW_RANDOM_TX4939) += tx4939-rng.o
obj-$(CONFIG_HW_RANDOM_MXC_RNGA) += mxc-rnga.o
obj-$(CONFIG_HW_RANDOM_IMX_RNGC) += imx-rngc.o
obj-$(CONFIG_HW_RANDOM_INGENIC_RNG) += ingenic-rng.o
diff --git a/drivers/char/hw_random/tx4939-rng.c b/drivers/char/hw_random/tx4939-rng.c
deleted file mode 100644
index c8bd34e740fd..000000000000
--- a/drivers/char/hw_random/tx4939-rng.c
+++ /dev/null
@@ -1,157 +0,0 @@
-/*
- * RNG driver for TX4939 Random Number Generators (RNG)
- *
- * Copyright (C) 2009 Atsushi Nemoto <anemo@mba.ocn.ne.jp>
- *
- * This file is subject to the terms and conditions of the GNU General Public
- * License. See the file "COPYING" in the main directory of this archive
- * for more details.
- */
-#include <linux/err.h>
-#include <linux/module.h>
-#include <linux/kernel.h>
-#include <linux/init.h>
-#include <linux/delay.h>
-#include <linux/io.h>
-#include <linux/platform_device.h>
-#include <linux/hw_random.h>
-#include <linux/gfp.h>
-
-#define TX4939_RNG_RCSR 0x00000000
-#define TX4939_RNG_ROR(n) (0x00000018 + (n) * 8)
-
-#define TX4939_RNG_RCSR_INTE 0x00000008
-#define TX4939_RNG_RCSR_RST 0x00000004
-#define TX4939_RNG_RCSR_FIN 0x00000002
-#define TX4939_RNG_RCSR_ST 0x00000001
-
-struct tx4939_rng {
- struct hwrng rng;
- void __iomem *base;
- u64 databuf[3];
- unsigned int data_avail;
-};
-
-static void rng_io_start(void)
-{
-#ifndef CONFIG_64BIT
- /*
- * readq is reading a 64-bit register using a 64-bit load. On
- * a 32-bit kernel however interrupts or any other processor
- * exception would clobber the upper 32-bit of the processor
- * register so interrupts need to be disabled.
- */
- local_irq_disable();
-#endif
-}
-
-static void rng_io_end(void)
-{
-#ifndef CONFIG_64BIT
- local_irq_enable();
-#endif
-}
-
-static u64 read_rng(void __iomem *base, unsigned int offset)
-{
- return ____raw_readq(base + offset);
-}
-
-static void write_rng(u64 val, void __iomem *base, unsigned int offset)
-{
- return ____raw_writeq(val, base + offset);
-}
-
-static int tx4939_rng_data_present(struct hwrng *rng, int wait)
-{
- struct tx4939_rng *rngdev = container_of(rng, struct tx4939_rng, rng);
- int i;
-
- if (rngdev->data_avail)
- return rngdev->data_avail;
- for (i = 0; i < 20; i++) {
- rng_io_start();
- if (!(read_rng(rngdev->base, TX4939_RNG_RCSR)
- & TX4939_RNG_RCSR_ST)) {
- rngdev->databuf[0] =
- read_rng(rngdev->base, TX4939_RNG_ROR(0));
- rngdev->databuf[1] =
- read_rng(rngdev->base, TX4939_RNG_ROR(1));
- rngdev->databuf[2] =
- read_rng(rngdev->base, TX4939_RNG_ROR(2));
- rngdev->data_avail =
- sizeof(rngdev->databuf) / sizeof(u32);
- /* Start RNG */
- write_rng(TX4939_RNG_RCSR_ST,
- rngdev->base, TX4939_RNG_RCSR);
- wait = 0;
- }
- rng_io_end();
- if (!wait)
- break;
- /* 90 bus clock cycles by default for generation */
- ndelay(90 * 5);
- }
- return rngdev->data_avail;
-}
-
-static int tx4939_rng_data_read(struct hwrng *rng, u32 *buffer)
-{
- struct tx4939_rng *rngdev = container_of(rng, struct tx4939_rng, rng);
-
- rngdev->data_avail--;
- *buffer = *((u32 *)&rngdev->databuf + rngdev->data_avail);
- return sizeof(u32);
-}
-
-static int __init tx4939_rng_probe(struct platform_device *dev)
-{
- struct tx4939_rng *rngdev;
- int i;
-
- rngdev = devm_kzalloc(&dev->dev, sizeof(*rngdev), GFP_KERNEL);
- if (!rngdev)
- return -ENOMEM;
- rngdev->base = devm_platform_ioremap_resource(dev, 0);
- if (IS_ERR(rngdev->base))
- return PTR_ERR(rngdev->base);
-
- rngdev->rng.name = dev_name(&dev->dev);
- rngdev->rng.data_present = tx4939_rng_data_present;
- rngdev->rng.data_read = tx4939_rng_data_read;
-
- rng_io_start();
- /* Reset RNG */
- write_rng(TX4939_RNG_RCSR_RST, rngdev->base, TX4939_RNG_RCSR);
- write_rng(0, rngdev->base, TX4939_RNG_RCSR);
- /* Start RNG */
- write_rng(TX4939_RNG_RCSR_ST, rngdev->base, TX4939_RNG_RCSR);
- rng_io_end();
- /*
- * Drop first two results. From the datasheet:
- * The quality of the random numbers generated immediately
- * after reset can be insufficient. Therefore, do not use
- * random numbers obtained from the first and second
- * generations; use the ones from the third or subsequent
- * generation.
- */
- for (i = 0; i < 2; i++) {
- rngdev->data_avail = 0;
- if (!tx4939_rng_data_present(&rngdev->rng, 1))
- return -EIO;
- }
-
- platform_set_drvdata(dev, rngdev);
- return devm_hwrng_register(&dev->dev, &rngdev->rng);
-}
-
-static struct platform_driver tx4939_rng_driver = {
- .driver = {
- .name = "tx4939-rng",
- },
-};
-
-module_platform_driver_probe(tx4939_rng_driver, tx4939_rng_probe);
-
-MODULE_DESCRIPTION("H/W Random Number Generator (RNG) driver for TX4939");
-MODULE_LICENSE("GPL");
--
2.29.2