^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1) // SPDX-License-Identifier: GPL-2.0-only
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 2) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 3) * Generic PowerPC 44x RNG driver
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 4) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 5) * Copyright 2011 IBM Corporation
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 6) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 7)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 8) #include <linux/module.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 9) #include <linux/kernel.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 10) #include <linux/interrupt.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 11) #include <linux/platform_device.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 12) #include <linux/hw_random.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 13) #include <linux/delay.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 14) #include <linux/of_address.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 15) #include <linux/of_platform.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 16) #include <linux/io.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 17)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 18) #include "crypto4xx_core.h"
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 19) #include "crypto4xx_trng.h"
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 20) #include "crypto4xx_reg_def.h"
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 21)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 22) #define PPC4XX_TRNG_CTRL 0x0008
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 23) #define PPC4XX_TRNG_CTRL_DALM 0x20
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 24) #define PPC4XX_TRNG_STAT 0x0004
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 25) #define PPC4XX_TRNG_STAT_B 0x1
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 26) #define PPC4XX_TRNG_DATA 0x0000
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 27)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 28) static int ppc4xx_trng_data_present(struct hwrng *rng, int wait)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 29) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 30) struct crypto4xx_device *dev = (void *)rng->priv;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 31) int busy, i, present = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 32)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 33) for (i = 0; i < 20; i++) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 34) busy = (in_le32(dev->trng_base + PPC4XX_TRNG_STAT) &
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 35) PPC4XX_TRNG_STAT_B);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 36) if (!busy || !wait) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 37) present = 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 38) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 39) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 40) udelay(10);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 41) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 42) return present;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 43) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 44)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 45) static int ppc4xx_trng_data_read(struct hwrng *rng, u32 *data)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 46) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 47) struct crypto4xx_device *dev = (void *)rng->priv;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 48) *data = in_le32(dev->trng_base + PPC4XX_TRNG_DATA);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 49) return 4;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 50) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 51)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 52) static void ppc4xx_trng_enable(struct crypto4xx_device *dev, bool enable)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 53) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 54) u32 device_ctrl;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 55)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 56) device_ctrl = readl(dev->ce_base + CRYPTO4XX_DEVICE_CTRL);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 57) if (enable)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 58) device_ctrl |= PPC4XX_TRNG_EN;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 59) else
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 60) device_ctrl &= ~PPC4XX_TRNG_EN;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 61) writel(device_ctrl, dev->ce_base + CRYPTO4XX_DEVICE_CTRL);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 62) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 63)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 64) static const struct of_device_id ppc4xx_trng_match[] = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 65) { .compatible = "ppc4xx-rng", },
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 66) { .compatible = "amcc,ppc460ex-rng", },
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 67) { .compatible = "amcc,ppc440epx-rng", },
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 68) {},
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 69) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 70)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 71) void ppc4xx_trng_probe(struct crypto4xx_core_device *core_dev)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 72) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 73) struct crypto4xx_device *dev = core_dev->dev;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 74) struct device_node *trng = NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 75) struct hwrng *rng = NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 76) int err;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 77)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 78) /* Find the TRNG device node and map it */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 79) trng = of_find_matching_node(NULL, ppc4xx_trng_match);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 80) if (!trng || !of_device_is_available(trng)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 81) of_node_put(trng);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 82) return;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 83) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 84)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 85) dev->trng_base = of_iomap(trng, 0);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 86) of_node_put(trng);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 87) if (!dev->trng_base)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 88) goto err_out;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 89)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 90) rng = kzalloc(sizeof(*rng), GFP_KERNEL);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 91) if (!rng)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 92) goto err_out;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 93)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 94) rng->name = KBUILD_MODNAME;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 95) rng->data_present = ppc4xx_trng_data_present;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 96) rng->data_read = ppc4xx_trng_data_read;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 97) rng->priv = (unsigned long) dev;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 98) core_dev->trng = rng;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 99) ppc4xx_trng_enable(dev, true);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 100) out_le32(dev->trng_base + PPC4XX_TRNG_CTRL, PPC4XX_TRNG_CTRL_DALM);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 101) err = devm_hwrng_register(core_dev->device, core_dev->trng);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 102) if (err) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 103) ppc4xx_trng_enable(dev, false);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 104) dev_err(core_dev->device, "failed to register hwrng (%d).\n",
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 105) err);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 106) goto err_out;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 107) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 108) return;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 109)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 110) err_out:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 111) iounmap(dev->trng_base);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 112) kfree(rng);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 113) dev->trng_base = NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 114) core_dev->trng = NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 115) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 116)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 117) void ppc4xx_trng_remove(struct crypto4xx_core_device *core_dev)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 118) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 119) if (core_dev && core_dev->trng) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 120) struct crypto4xx_device *dev = core_dev->dev;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 121)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 122) devm_hwrng_unregister(core_dev->device, core_dev->trng);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 123) ppc4xx_trng_enable(dev, false);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 124) iounmap(dev->trng_base);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 125) kfree(core_dev->trng);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 126) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 127) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 128)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 129) MODULE_ALIAS("ppc4xx_rng");
Orange Pi5 kernel
Deprecated Linux kernel 5.10.110 for OrangePi 5/5B/5+ boards
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