diff options
Diffstat (limited to 'drivers/nvmem/sunxi_sid.c')
| -rw-r--r-- | drivers/nvmem/sunxi_sid.c | 115 |
1 files changed, 46 insertions, 69 deletions
diff --git a/drivers/nvmem/sunxi_sid.c b/drivers/nvmem/sunxi_sid.c index 570a2e354f30..a079a80ddf2c 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> @@ -35,13 +26,6 @@ #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, -}; - struct sunxi_sid_cfg { u32 value_offset; u32 size; @@ -53,33 +37,12 @@ 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; - /* Offset the read operation to the real position of SID */ - offset += sid->value_offset; - - while (bytes--) - *buf++ = sunxi_sid_read_byte(sid, offset++); + memcpy_fromio(val, sid->base + sid->value_offset + offset, bytes); return 0; } @@ -115,36 +78,34 @@ static int sun8i_sid_register_readout(const struct sunxi_sid *sid, * to be not reliable at all. * Read by the registers instead. */ -static int sun8i_sid_read_byte_by_reg(const struct sunxi_sid *sid, - const unsigned int offset, - u8 *out) -{ - u32 word; - int ret; - - ret = sun8i_sid_register_readout(sid, offset & ~0x03, &word); - - if (ret) - return ret; - - *out = (word >> ((offset & 0x3) * 8)) & 0xff; - - return 0; -} - static int sun8i_sid_read_by_reg(void *context, unsigned int offset, void *val, size_t bytes) { struct sunxi_sid *sid = context; - u8 *buf = val; + u32 word; int ret; - while (bytes--) { - ret = sun8i_sid_read_byte_by_reg(sid, offset++, buf++); + /* .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; } @@ -152,9 +113,10 @@ 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 i, size; + int size; char *randomness; const struct sunxi_sid_cfg *cfg; @@ -174,14 +136,23 @@ static int sunxi_sid_probe(struct platform_device *pdev) size = cfg->size; - econfig.size = size; - econfig.dev = dev; + nvmem_cfg = devm_kzalloc(dev, sizeof(*nvmem_cfg), GFP_KERNEL); + if (!nvmem_cfg) + return -ENOMEM; + + nvmem_cfg->dev = dev; + nvmem_cfg->name = "sunxi-sid"; + 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) - econfig.reg_read = sun8i_sid_read_by_reg; + nvmem_cfg->reg_read = sun8i_sid_read_by_reg; else - econfig.reg_read = sunxi_sid_read; - econfig.priv = sid; - nvmem = devm_nvmem_register(dev, &econfig); + nvmem_cfg->reg_read = sunxi_sid_read; + + nvmem = devm_nvmem_register(dev, nvmem_cfg); if (IS_ERR(nvmem)) return PTR_ERR(nvmem); @@ -189,9 +160,7 @@ static int sunxi_sid_probe(struct platform_device *pdev) if (!randomness) return -ENOMEM; - for (i = 0; i < size; i++) - econfig.reg_read(sid, i, &randomness[i], 1); - + nvmem_cfg->reg_read(sid, 0, randomness, size); add_device_randomness(randomness, size); kfree(randomness); @@ -219,11 +188,19 @@ static const struct sunxi_sid_cfg sun50i_a64_cfg = { .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,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); |