linux/drivers/nvmem/sunxi_sid.c

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// 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>
*/
#include <linux/device.h>
#include <linux/io.h>
#include <linux/iopoll.h>
#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>
/* Registers and special values for doing register-based SID readout on H3 */
#define SUN8I_SID_PRCTL 0x40
#define SUN8I_SID_RDKEY 0x60
#define SUN8I_SID_OFFSET_MASK 0x1FF
#define SUN8I_SID_OFFSET_SHIFT 16
#define SUN8I_SID_OP_LOCK (0xAC << 8)
#define SUN8I_SID_READ BIT(1)
struct sunxi_sid_cfg {
u32 value_offset;
u32 size;
bool need_register_readout;
};
struct sunxi_sid {
void __iomem *base;
u32 value_offset;
};
static int sunxi_sid_read(void *context, unsigned int offset,
void *val, size_t bytes)
{
struct sunxi_sid *sid = context;
memcpy_fromio(val, sid->base + sid->value_offset + offset, bytes);
return 0;
}
static int sun8i_sid_register_readout(const struct sunxi_sid *sid,
const unsigned int offset,
u32 *out)
{
u32 reg_val;
int ret;
/* Set word, lock access, and set read command */
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);
ret = readl_poll_timeout(sid->base + SUN8I_SID_PRCTL, reg_val,
!(reg_val & SUN8I_SID_READ), 100, 250000);
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 size;
char *randomness;
const struct sunxi_sid_cfg *cfg;
sid = devm_kzalloc(dev, sizeof(*sid), GFP_KERNEL);
if (!sid)
return -ENOMEM;
cfg = of_device_get_match_data(dev);
if (!cfg)
return -EINVAL;
sid->value_offset = cfg->value_offset;
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
sid->base = devm_ioremap_resource(dev, res);
if (IS_ERR(sid->base))
return PTR_ERR(sid->base);
size = cfg->size;
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)
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);
treewide: kzalloc() -> kcalloc() The kzalloc() function has a 2-factor argument form, kcalloc(). This patch replaces cases of: kzalloc(a * b, gfp) with: kcalloc(a * b, gfp) as well as handling cases of: kzalloc(a * b * c, gfp) with: kzalloc(array3_size(a, b, c), gfp) as it's slightly less ugly than: kzalloc_array(array_size(a, b), c, gfp) This does, however, attempt to ignore constant size factors like: kzalloc(4 * 1024, gfp) though any constants defined via macros get caught up in the conversion. Any factors with a sizeof() of "unsigned char", "char", and "u8" were dropped, since they're redundant. The Coccinelle script used for this was: // Fix redundant parens around sizeof(). @@ type TYPE; expression THING, E; @@ ( kzalloc( - (sizeof(TYPE)) * E + sizeof(TYPE) * E , ...) | kzalloc( - (sizeof(THING)) * E + sizeof(THING) * E , ...) ) // Drop single-byte sizes and redundant parens. @@ expression COUNT; typedef u8; typedef __u8; @@ ( kzalloc( - sizeof(u8) * (COUNT) + COUNT , ...) | kzalloc( - sizeof(__u8) * (COUNT) + COUNT , ...) | kzalloc( - sizeof(char) * (COUNT) + COUNT , ...) | kzalloc( - sizeof(unsigned char) * (COUNT) + COUNT , ...) | kzalloc( - sizeof(u8) * COUNT + COUNT , ...) | kzalloc( - sizeof(__u8) * COUNT + COUNT , ...) | kzalloc( - sizeof(char) * COUNT + COUNT , ...) | kzalloc( - sizeof(unsigned char) * COUNT + COUNT , ...) ) // 2-factor product with sizeof(type/expression) and identifier or constant. @@ type TYPE; expression THING; identifier COUNT_ID; constant COUNT_CONST; @@ ( - kzalloc + kcalloc ( - sizeof(TYPE) * (COUNT_ID) + COUNT_ID, sizeof(TYPE) , ...) | - kzalloc + kcalloc ( - sizeof(TYPE) * COUNT_ID + COUNT_ID, sizeof(TYPE) , ...) | - kzalloc + kcalloc ( - sizeof(TYPE) * (COUNT_CONST) + COUNT_CONST, sizeof(TYPE) , ...) | - kzalloc + kcalloc ( - sizeof(TYPE) * COUNT_CONST + COUNT_CONST, sizeof(TYPE) , ...) | - kzalloc + kcalloc ( - sizeof(THING) * (COUNT_ID) + COUNT_ID, sizeof(THING) , ...) | - kzalloc + kcalloc ( - sizeof(THING) * COUNT_ID + COUNT_ID, sizeof(THING) , ...) | - kzalloc + kcalloc ( - sizeof(THING) * (COUNT_CONST) + COUNT_CONST, sizeof(THING) , ...) | - kzalloc + kcalloc ( - sizeof(THING) * COUNT_CONST + COUNT_CONST, sizeof(THING) , ...) ) // 2-factor product, only identifiers. @@ identifier SIZE, COUNT; @@ - kzalloc + kcalloc ( - SIZE * COUNT + COUNT, SIZE , ...) // 3-factor product with 1 sizeof(type) or sizeof(expression), with // redundant parens removed. @@ expression THING; identifier STRIDE, COUNT; type TYPE; @@ ( kzalloc( - sizeof(TYPE) * (COUNT) * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | kzalloc( - sizeof(TYPE) * (COUNT) * STRIDE + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | kzalloc( - sizeof(TYPE) * COUNT * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | kzalloc( - sizeof(TYPE) * COUNT * STRIDE + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | kzalloc( - sizeof(THING) * (COUNT) * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) | kzalloc( - sizeof(THING) * (COUNT) * STRIDE + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) | kzalloc( - sizeof(THING) * COUNT * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) | kzalloc( - sizeof(THING) * COUNT * STRIDE + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) ) // 3-factor product with 2 sizeof(variable), with redundant parens removed. @@ expression THING1, THING2; identifier COUNT; type TYPE1, TYPE2; @@ ( kzalloc( - sizeof(TYPE1) * sizeof(TYPE2) * COUNT + array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2)) , ...) | kzalloc( - sizeof(TYPE1) * sizeof(THING2) * (COUNT) + array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2)) , ...) | kzalloc( - sizeof(THING1) * sizeof(THING2) * COUNT + array3_size(COUNT, sizeof(THING1), sizeof(THING2)) , ...) | kzalloc( - sizeof(THING1) * sizeof(THING2) * (COUNT) + array3_size(COUNT, sizeof(THING1), sizeof(THING2)) , ...) | kzalloc( - sizeof(TYPE1) * sizeof(THING2) * COUNT + array3_size(COUNT, sizeof(TYPE1), sizeof(THING2)) , ...) | kzalloc( - sizeof(TYPE1) * sizeof(THING2) * (COUNT) + array3_size(COUNT, sizeof(TYPE1), sizeof(THING2)) , ...) ) // 3-factor product, only identifiers, with redundant parens removed. @@ identifier STRIDE, SIZE, COUNT; @@ ( kzalloc( - (COUNT) * STRIDE * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) | kzalloc( - COUNT * (STRIDE) * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) | kzalloc( - COUNT * STRIDE * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | kzalloc( - (COUNT) * (STRIDE) * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) | kzalloc( - COUNT * (STRIDE) * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | kzalloc( - (COUNT) * STRIDE * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | kzalloc( - (COUNT) * (STRIDE) * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | kzalloc( - COUNT * STRIDE * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) ) // Any remaining multi-factor products, first at least 3-factor products, // when they're not all constants... @@ expression E1, E2, E3; constant C1, C2, C3; @@ ( kzalloc(C1 * C2 * C3, ...) | kzalloc( - (E1) * E2 * E3 + array3_size(E1, E2, E3) , ...) | kzalloc( - (E1) * (E2) * E3 + array3_size(E1, E2, E3) , ...) | kzalloc( - (E1) * (E2) * (E3) + array3_size(E1, E2, E3) , ...) | kzalloc( - E1 * E2 * E3 + array3_size(E1, E2, E3) , ...) ) // And then all remaining 2 factors products when they're not all constants, // keeping sizeof() as the second factor argument. @@ expression THING, E1, E2; type TYPE; constant C1, C2, C3; @@ ( kzalloc(sizeof(THING) * C2, ...) | kzalloc(sizeof(TYPE) * C2, ...) | kzalloc(C1 * C2 * C3, ...) | kzalloc(C1 * C2, ...) | - kzalloc + kcalloc ( - sizeof(TYPE) * (E2) + E2, sizeof(TYPE) , ...) | - kzalloc + kcalloc ( - sizeof(TYPE) * E2 + E2, sizeof(TYPE) , ...) | - kzalloc + kcalloc ( - sizeof(THING) * (E2) + E2, sizeof(THING) , ...) | - kzalloc + kcalloc ( - sizeof(THING) * E2 + E2, sizeof(THING) , ...) | - kzalloc + kcalloc ( - (E1) * E2 + E1, E2 , ...) | - kzalloc + kcalloc ( - (E1) * (E2) + E1, E2 , ...) | - kzalloc + kcalloc ( - E1 * E2 + E1, E2 , ...) ) Signed-off-by: Kees Cook <keescook@chromium.org>
2018-06-12 21:03:40 +00:00
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;
}
static const struct sunxi_sid_cfg sun4i_a10_cfg = {
.size = 0x10,
};
static const struct sunxi_sid_cfg sun7i_a20_cfg = {
.size = 0x200,
};
static const struct sunxi_sid_cfg sun8i_h3_cfg = {
.value_offset = 0x200,
.size = 0x100,
.need_register_readout = true,
};
static const struct sunxi_sid_cfg sun50i_a64_cfg = {
.value_offset = 0x200,
.size = 0x100,
.need_register_readout = true,
};
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);
static struct platform_driver sunxi_sid_driver = {
.probe = sunxi_sid_probe,
.driver = {
.name = "eeprom-sunxi-sid",
.of_match_table = sunxi_sid_of_match,
},
};
module_platform_driver(sunxi_sid_driver);
MODULE_AUTHOR("Oliver Schinagl <oliver@schinagl.nl>");
MODULE_DESCRIPTION("Allwinner sunxi security id driver");
MODULE_LICENSE("GPL");