123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159 |
- // SPDX-License-Identifier: GPL-2.0-only
- /*
- * Copyright (c) Vaisala Oyj. All rights reserved.
- */
- #include <common.h>
- #include <bootcount.h>
- #include <dm.h>
- #include <dm/device_compat.h>
- #include <linux/ioport.h>
- #include <regmap.h>
- #include <syscon.h>
- #define BYTES_TO_BITS(bytes) ((bytes) << 3)
- #define GEN_REG_MASK(val_size, val_addr) \
- (GENMASK(BYTES_TO_BITS(val_size) - 1, 0) \
- << (!!((val_addr) == 0x02) * BYTES_TO_BITS(2)))
- #define GET_DEFAULT_VALUE(val_size) \
- (CONFIG_SYS_BOOTCOUNT_MAGIC >> \
- (BYTES_TO_BITS((sizeof(u32) - (val_size)))))
- /**
- * struct bootcount_syscon_priv - driver's private data
- *
- * @regmap: syscon regmap
- * @reg_addr: register address used to store the bootcount value
- * @size: size of the bootcount value (2 or 4 bytes)
- * @magic: magic used to validate/save the bootcount value
- * @magic_mask: magic value bitmask
- * @reg_mask: mask used to identify the location of the bootcount value
- * in the register when 2 bytes length is used
- * @shift: value used to extract the botcount value from the register
- */
- struct bootcount_syscon_priv {
- struct regmap *regmap;
- fdt_addr_t reg_addr;
- fdt_size_t size;
- u32 magic;
- u32 magic_mask;
- u32 reg_mask;
- int shift;
- };
- static int bootcount_syscon_set(struct udevice *dev, const u32 val)
- {
- struct bootcount_syscon_priv *priv = dev_get_priv(dev);
- u32 regval;
- if ((val & priv->magic_mask) != 0)
- return -EINVAL;
- regval = (priv->magic & priv->magic_mask) | (val & ~priv->magic_mask);
- if (priv->size == 2) {
- regval &= 0xffff;
- regval |= (regval & 0xffff) << BYTES_TO_BITS(priv->size);
- }
- debug("%s: Prepare to write reg value: 0x%08x with register mask: 0x%08x\n",
- __func__, regval, priv->reg_mask);
- return regmap_update_bits(priv->regmap, priv->reg_addr, priv->reg_mask,
- regval);
- }
- static int bootcount_syscon_get(struct udevice *dev, u32 *val)
- {
- struct bootcount_syscon_priv *priv = dev_get_priv(dev);
- u32 regval;
- int ret;
- ret = regmap_read(priv->regmap, priv->reg_addr, ®val);
- if (ret)
- return ret;
- regval &= priv->reg_mask;
- regval >>= priv->shift;
- if ((regval & priv->magic_mask) == (priv->magic & priv->magic_mask)) {
- *val = regval & ~priv->magic_mask;
- } else {
- dev_err(dev, "%s: Invalid bootcount magic\n", __func__);
- return -EINVAL;
- }
- debug("%s: Read bootcount value: 0x%08x from regval: 0x%08x\n",
- __func__, *val, regval);
- return 0;
- }
- static int bootcount_syscon_of_to_plat(struct udevice *dev)
- {
- struct bootcount_syscon_priv *priv = dev_get_priv(dev);
- fdt_addr_t bootcount_offset;
- fdt_size_t reg_size;
- priv->regmap = syscon_regmap_lookup_by_phandle(dev, "syscon");
- if (IS_ERR(priv->regmap)) {
- dev_err(dev, "%s: Unable to find regmap (%ld)\n", __func__,
- PTR_ERR(priv->regmap));
- return PTR_ERR(priv->regmap);
- }
- priv->reg_addr = dev_read_addr_size_name(dev, "syscon_reg", ®_size);
- if (priv->reg_addr == FDT_ADDR_T_NONE) {
- dev_err(dev, "%s: syscon_reg address not found\n", __func__);
- return -EINVAL;
- }
- if (reg_size != 4) {
- dev_err(dev, "%s: Unsupported register size: %d\n", __func__,
- reg_size);
- return -EINVAL;
- }
- bootcount_offset = dev_read_addr_size_name(dev, "offset", &priv->size);
- if (bootcount_offset == FDT_ADDR_T_NONE) {
- dev_err(dev, "%s: offset configuration not found\n", __func__);
- return -EINVAL;
- }
- if (bootcount_offset + priv->size > reg_size) {
- dev_err(dev,
- "%s: Bootcount value doesn't fit in the reserved space\n",
- __func__);
- return -EINVAL;
- }
- if (priv->size != 2 && priv->size != 4) {
- dev_err(dev,
- "%s: Driver supports only 2 and 4 bytes bootcount size\n",
- __func__);
- return -EINVAL;
- }
- priv->magic = GET_DEFAULT_VALUE(priv->size);
- priv->magic_mask = GENMASK(BYTES_TO_BITS(priv->size) - 1,
- BYTES_TO_BITS(priv->size >> 1));
- priv->shift = !!(bootcount_offset == 0x02) * BYTES_TO_BITS(priv->size);
- priv->reg_mask = GEN_REG_MASK(priv->size, bootcount_offset);
- return 0;
- }
- static const struct bootcount_ops bootcount_syscon_ops = {
- .get = bootcount_syscon_get,
- .set = bootcount_syscon_set,
- };
- static const struct udevice_id bootcount_syscon_ids[] = {
- { .compatible = "u-boot,bootcount-syscon" },
- {}
- };
- U_BOOT_DRIVER(bootcount_syscon) = {
- .name = "bootcount-syscon",
- .id = UCLASS_BOOTCOUNT,
- .of_to_plat = bootcount_syscon_of_to_plat,
- .priv_auto = sizeof(struct bootcount_syscon_priv),
- .of_match = bootcount_syscon_ids,
- .ops = &bootcount_syscon_ops,
- };
|