diff options
Diffstat (limited to 'drivers/nvmem/sunxi_sid.c')
| -rw-r--r-- | drivers/nvmem/sunxi_sid.c | 184 |
1 files changed, 97 insertions, 87 deletions
diff --git a/drivers/nvmem/sunxi_sid.c b/drivers/nvmem/sunxi_sid.c index 0d6648be93b8..ba14a76208ab 100644 --- a/drivers/nvmem/sunxi_sid.c +++ b/drivers/nvmem/sunxi_sid.c @@ -1,18 +1,9 @@ +// SPDX-License-Identifier: GPL-2.0+ /* * Allwinner sunXi SoCs Security ID support. * * Copyright (c) 2013 Oliver Schinagl <oliver@schinagl.nl> * Copyright (C) 2014 Maxime Ripard <maxime.ripard@free-electrons.com> - * - * This program is free software; you can redistribute it and/or modify - * it under the terms of the GNU General Public License as published by - * the Free Software Foundation; either version 2 of the License, or - * (at your option) any later version. - * - * This program is distributed in the hope that it will be useful, - * but WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the - * GNU General Public License for more details. */ #include <linux/device.h> @@ -21,7 +12,6 @@ #include <linux/module.h> #include <linux/nvmem-provider.h> #include <linux/of.h> -#include <linux/of_device.h> #include <linux/platform_device.h> #include <linux/slab.h> #include <linux/random.h> @@ -35,14 +25,6 @@ #define SUN8I_SID_OP_LOCK (0xAC << 8) #define SUN8I_SID_READ BIT(1) -static struct nvmem_config econfig = { - .name = "sunxi-sid", - .read_only = true, - .stride = 4, - .word_size = 1, - .owner = THIS_MODULE, -}; - struct sunxi_sid_cfg { u32 value_offset; u32 size; @@ -54,45 +36,38 @@ struct sunxi_sid { u32 value_offset; }; -/* We read the entire key, due to a 32 bit read alignment requirement. Since we - * want to return the requested byte, this results in somewhat slower code and - * uses 4 times more reads as needed but keeps code simpler. Since the SID is - * only very rarely probed, this is not really an issue. - */ -static u8 sunxi_sid_read_byte(const struct sunxi_sid *sid, - const unsigned int offset) -{ - u32 sid_key; - - sid_key = ioread32be(sid->base + round_down(offset, 4)); - sid_key >>= (offset % 4) * 8; - - return sid_key; /* Only return the last byte */ -} - static int sunxi_sid_read(void *context, unsigned int offset, void *val, size_t bytes) { struct sunxi_sid *sid = context; - u8 *buf = val; + u32 word; - /* Offset the read operation to the real position of SID */ - offset += sid->value_offset; + /* .stride = 4 so offset is guaranteed to be aligned */ + __ioread32_copy(val, sid->base + sid->value_offset + offset, bytes / 4); - while (bytes--) - *buf++ = sunxi_sid_read_byte(sid, offset++); + val += round_down(bytes, 4); + offset += round_down(bytes, 4); + bytes = bytes % 4; + + if (!bytes) + return 0; + + /* Handle any trailing bytes */ + word = readl_relaxed(sid->base + sid->value_offset + offset); + memcpy(val, &word, bytes); return 0; } static int sun8i_sid_register_readout(const struct sunxi_sid *sid, - const unsigned int word) + const unsigned int offset, + u32 *out) { u32 reg_val; int ret; /* Set word, lock access, and set read command */ - reg_val = (word & SUN8I_SID_OFFSET_MASK) + reg_val = (offset & SUN8I_SID_OFFSET_MASK) << SUN8I_SID_OFFSET_SHIFT; reg_val |= SUN8I_SID_OP_LOCK | SUN8I_SID_READ; writel(reg_val, sid->base + SUN8I_SID_PRCTL); @@ -102,17 +77,57 @@ static int sun8i_sid_register_readout(const struct sunxi_sid *sid, if (ret) return ret; + if (out) + *out = readl(sid->base + SUN8I_SID_RDKEY); + writel(0, sid->base + SUN8I_SID_PRCTL); + + return 0; +} + +/* + * On Allwinner H3, the value on the 0x200 offset of the SID controller seems + * to be not reliable at all. + * Read by the registers instead. + */ +static int sun8i_sid_read_by_reg(void *context, unsigned int offset, + void *val, size_t bytes) +{ + struct sunxi_sid *sid = context; + u32 word; + int ret; + + /* .stride = 4 so offset is guaranteed to be aligned */ + while (bytes >= 4) { + ret = sun8i_sid_register_readout(sid, offset, val); + if (ret) + return ret; + + val += 4; + offset += 4; + bytes -= 4; + } + + if (!bytes) + return 0; + + /* Handle any trailing bytes */ + ret = sun8i_sid_register_readout(sid, offset, &word); + if (ret) + return ret; + + memcpy(val, &word, bytes); + return 0; } static int sunxi_sid_probe(struct platform_device *pdev) { struct device *dev = &pdev->dev; - struct resource *res; + struct nvmem_config *nvmem_cfg; struct nvmem_device *nvmem; struct sunxi_sid *sid; - int ret, i, size; + int size; char *randomness; const struct sunxi_sid_cfg *cfg; @@ -125,64 +140,45 @@ static int sunxi_sid_probe(struct platform_device *pdev) return -EINVAL; sid->value_offset = cfg->value_offset; - res = platform_get_resource(pdev, IORESOURCE_MEM, 0); - sid->base = devm_ioremap_resource(dev, res); + sid->base = devm_platform_ioremap_resource(pdev, 0); if (IS_ERR(sid->base)) return PTR_ERR(sid->base); size = cfg->size; - if (cfg->need_register_readout) { - /* - * H3's SID controller have a bug that the value at 0x200 - * offset is not the correct value when the hardware is reseted. - * However, after doing a register-based read operation, the - * value become right. - * Do a full read operation here, but ignore its value - * (as it's more fast to read by direct MMIO value than - * with registers) - */ - for (i = 0; i < (size >> 2); i++) { - ret = sun8i_sid_register_readout(sid, i); - if (ret) - return ret; - } - } + nvmem_cfg = devm_kzalloc(dev, sizeof(*nvmem_cfg), GFP_KERNEL); + if (!nvmem_cfg) + return -ENOMEM; - econfig.size = size; - econfig.dev = dev; - econfig.reg_read = sunxi_sid_read; - econfig.priv = sid; - nvmem = nvmem_register(&econfig); + nvmem_cfg->dev = dev; + nvmem_cfg->name = "sunxi-sid"; + nvmem_cfg->type = NVMEM_TYPE_OTP; + nvmem_cfg->add_legacy_fixed_of_cells = true; + nvmem_cfg->read_only = true; + nvmem_cfg->size = cfg->size; + nvmem_cfg->word_size = 1; + nvmem_cfg->stride = 4; + nvmem_cfg->priv = sid; + if (cfg->need_register_readout) + nvmem_cfg->reg_read = sun8i_sid_read_by_reg; + else + nvmem_cfg->reg_read = sunxi_sid_read; + + nvmem = devm_nvmem_register(dev, nvmem_cfg); if (IS_ERR(nvmem)) return PTR_ERR(nvmem); - randomness = kzalloc(sizeof(u8) * (size), GFP_KERNEL); - if (!randomness) { - ret = -EINVAL; - goto err_unreg_nvmem; - } - - for (i = 0; i < size; i++) - randomness[i] = sunxi_sid_read_byte(sid, i); + randomness = kzalloc(size, GFP_KERNEL); + if (!randomness) + return -ENOMEM; + nvmem_cfg->reg_read(sid, 0, randomness, size); add_device_randomness(randomness, size); kfree(randomness); platform_set_drvdata(pdev, nvmem); return 0; - -err_unreg_nvmem: - nvmem_unregister(nvmem); - return ret; -} - -static int sunxi_sid_remove(struct platform_device *pdev) -{ - struct nvmem_device *nvmem = platform_get_drvdata(pdev); - - return nvmem_unregister(nvmem); } static const struct sunxi_sid_cfg sun4i_a10_cfg = { @@ -199,17 +195,31 @@ static const struct sunxi_sid_cfg sun8i_h3_cfg = { .need_register_readout = true, }; +static const struct sunxi_sid_cfg sun50i_a64_cfg = { + .value_offset = 0x200, + .size = 0x100, +}; + +static const struct sunxi_sid_cfg sun50i_h6_cfg = { + .value_offset = 0x200, + .size = 0x200, +}; + static const struct of_device_id sunxi_sid_of_match[] = { { .compatible = "allwinner,sun4i-a10-sid", .data = &sun4i_a10_cfg }, { .compatible = "allwinner,sun7i-a20-sid", .data = &sun7i_a20_cfg }, + { .compatible = "allwinner,sun8i-a83t-sid", .data = &sun50i_a64_cfg }, { .compatible = "allwinner,sun8i-h3-sid", .data = &sun8i_h3_cfg }, + { .compatible = "allwinner,sun20i-d1-sid", .data = &sun50i_a64_cfg }, + { .compatible = "allwinner,sun50i-a64-sid", .data = &sun50i_a64_cfg }, + { .compatible = "allwinner,sun50i-h5-sid", .data = &sun50i_a64_cfg }, + { .compatible = "allwinner,sun50i-h6-sid", .data = &sun50i_h6_cfg }, {/* sentinel */}, }; MODULE_DEVICE_TABLE(of, sunxi_sid_of_match); static struct platform_driver sunxi_sid_driver = { .probe = sunxi_sid_probe, - .remove = sunxi_sid_remove, .driver = { .name = "eeprom-sunxi-sid", .of_match_table = sunxi_sid_of_match, |