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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
commit | 2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch) | |
tree | 848558de17fb3008cdf4d861b01ac7781903ce39 /drivers/mmc/host/cqhci-crypto.c | |
parent | Initial commit. (diff) | |
download | linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.zip |
Adding upstream version 6.1.76.upstream/6.1.76
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/mmc/host/cqhci-crypto.c')
-rw-r--r-- | drivers/mmc/host/cqhci-crypto.c | 243 |
1 files changed, 243 insertions, 0 deletions
diff --git a/drivers/mmc/host/cqhci-crypto.c b/drivers/mmc/host/cqhci-crypto.c new file mode 100644 index 000000000..d5f4b6972 --- /dev/null +++ b/drivers/mmc/host/cqhci-crypto.c @@ -0,0 +1,243 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * CQHCI crypto engine (inline encryption) support + * + * Copyright 2020 Google LLC + */ + +#include <linux/blk-crypto.h> +#include <linux/blk-crypto-profile.h> +#include <linux/mmc/host.h> + +#include "cqhci-crypto.h" + +/* Map from blk-crypto modes to CQHCI crypto algorithm IDs and key sizes */ +static const struct cqhci_crypto_alg_entry { + enum cqhci_crypto_alg alg; + enum cqhci_crypto_key_size key_size; +} cqhci_crypto_algs[BLK_ENCRYPTION_MODE_MAX] = { + [BLK_ENCRYPTION_MODE_AES_256_XTS] = { + .alg = CQHCI_CRYPTO_ALG_AES_XTS, + .key_size = CQHCI_CRYPTO_KEY_SIZE_256, + }, +}; + +static inline struct cqhci_host * +cqhci_host_from_crypto_profile(struct blk_crypto_profile *profile) +{ + struct mmc_host *mmc = + container_of(profile, struct mmc_host, crypto_profile); + + return mmc->cqe_private; +} + +static int cqhci_crypto_program_key(struct cqhci_host *cq_host, + const union cqhci_crypto_cfg_entry *cfg, + int slot) +{ + u32 slot_offset = cq_host->crypto_cfg_register + slot * sizeof(*cfg); + int i; + + if (cq_host->ops->program_key) + return cq_host->ops->program_key(cq_host, cfg, slot); + + /* Clear CFGE */ + cqhci_writel(cq_host, 0, slot_offset + 16 * sizeof(cfg->reg_val[0])); + + /* Write the key */ + for (i = 0; i < 16; i++) { + cqhci_writel(cq_host, le32_to_cpu(cfg->reg_val[i]), + slot_offset + i * sizeof(cfg->reg_val[0])); + } + /* Write dword 17 */ + cqhci_writel(cq_host, le32_to_cpu(cfg->reg_val[17]), + slot_offset + 17 * sizeof(cfg->reg_val[0])); + /* Write dword 16, which includes the new value of CFGE */ + cqhci_writel(cq_host, le32_to_cpu(cfg->reg_val[16]), + slot_offset + 16 * sizeof(cfg->reg_val[0])); + return 0; +} + +static int cqhci_crypto_keyslot_program(struct blk_crypto_profile *profile, + const struct blk_crypto_key *key, + unsigned int slot) + +{ + struct cqhci_host *cq_host = cqhci_host_from_crypto_profile(profile); + const union cqhci_crypto_cap_entry *ccap_array = + cq_host->crypto_cap_array; + const struct cqhci_crypto_alg_entry *alg = + &cqhci_crypto_algs[key->crypto_cfg.crypto_mode]; + u8 data_unit_mask = key->crypto_cfg.data_unit_size / 512; + int i; + int cap_idx = -1; + union cqhci_crypto_cfg_entry cfg = {}; + int err; + + BUILD_BUG_ON(CQHCI_CRYPTO_KEY_SIZE_INVALID != 0); + for (i = 0; i < cq_host->crypto_capabilities.num_crypto_cap; i++) { + if (ccap_array[i].algorithm_id == alg->alg && + ccap_array[i].key_size == alg->key_size && + (ccap_array[i].sdus_mask & data_unit_mask)) { + cap_idx = i; + break; + } + } + if (WARN_ON(cap_idx < 0)) + return -EOPNOTSUPP; + + cfg.data_unit_size = data_unit_mask; + cfg.crypto_cap_idx = cap_idx; + cfg.config_enable = CQHCI_CRYPTO_CONFIGURATION_ENABLE; + + if (ccap_array[cap_idx].algorithm_id == CQHCI_CRYPTO_ALG_AES_XTS) { + /* In XTS mode, the blk_crypto_key's size is already doubled */ + memcpy(cfg.crypto_key, key->raw, key->size/2); + memcpy(cfg.crypto_key + CQHCI_CRYPTO_KEY_MAX_SIZE/2, + key->raw + key->size/2, key->size/2); + } else { + memcpy(cfg.crypto_key, key->raw, key->size); + } + + err = cqhci_crypto_program_key(cq_host, &cfg, slot); + + memzero_explicit(&cfg, sizeof(cfg)); + return err; +} + +static int cqhci_crypto_clear_keyslot(struct cqhci_host *cq_host, int slot) +{ + /* + * Clear the crypto cfg on the device. Clearing CFGE + * might not be sufficient, so just clear the entire cfg. + */ + union cqhci_crypto_cfg_entry cfg = {}; + + return cqhci_crypto_program_key(cq_host, &cfg, slot); +} + +static int cqhci_crypto_keyslot_evict(struct blk_crypto_profile *profile, + const struct blk_crypto_key *key, + unsigned int slot) +{ + struct cqhci_host *cq_host = cqhci_host_from_crypto_profile(profile); + + return cqhci_crypto_clear_keyslot(cq_host, slot); +} + +/* + * The keyslot management operations for CQHCI crypto. + * + * Note that the block layer ensures that these are never called while the host + * controller is runtime-suspended. However, the CQE won't necessarily be + * "enabled" when these are called, i.e. CQHCI_ENABLE might not be set in the + * CQHCI_CFG register. But the hardware allows that. + */ +static const struct blk_crypto_ll_ops cqhci_crypto_ops = { + .keyslot_program = cqhci_crypto_keyslot_program, + .keyslot_evict = cqhci_crypto_keyslot_evict, +}; + +static enum blk_crypto_mode_num +cqhci_find_blk_crypto_mode(union cqhci_crypto_cap_entry cap) +{ + int i; + + for (i = 0; i < ARRAY_SIZE(cqhci_crypto_algs); i++) { + BUILD_BUG_ON(CQHCI_CRYPTO_KEY_SIZE_INVALID != 0); + if (cqhci_crypto_algs[i].alg == cap.algorithm_id && + cqhci_crypto_algs[i].key_size == cap.key_size) + return i; + } + return BLK_ENCRYPTION_MODE_INVALID; +} + +/** + * cqhci_crypto_init - initialize CQHCI crypto support + * @cq_host: a cqhci host + * + * If the driver previously set MMC_CAP2_CRYPTO and the CQE declares + * CQHCI_CAP_CS, initialize the crypto support. This involves reading the + * crypto capability registers, initializing the blk_crypto_profile, clearing + * all keyslots, and enabling 128-bit task descriptors. + * + * Return: 0 if crypto was initialized or isn't supported; whether + * MMC_CAP2_CRYPTO remains set indicates which one of those cases it is. + * Also can return a negative errno value on unexpected error. + */ +int cqhci_crypto_init(struct cqhci_host *cq_host) +{ + struct mmc_host *mmc = cq_host->mmc; + struct device *dev = mmc_dev(mmc); + struct blk_crypto_profile *profile = &mmc->crypto_profile; + unsigned int num_keyslots; + unsigned int cap_idx; + enum blk_crypto_mode_num blk_mode_num; + unsigned int slot; + int err = 0; + + if (!(mmc->caps2 & MMC_CAP2_CRYPTO) || + !(cqhci_readl(cq_host, CQHCI_CAP) & CQHCI_CAP_CS)) + goto out; + + cq_host->crypto_capabilities.reg_val = + cpu_to_le32(cqhci_readl(cq_host, CQHCI_CCAP)); + + cq_host->crypto_cfg_register = + (u32)cq_host->crypto_capabilities.config_array_ptr * 0x100; + + cq_host->crypto_cap_array = + devm_kcalloc(dev, cq_host->crypto_capabilities.num_crypto_cap, + sizeof(cq_host->crypto_cap_array[0]), GFP_KERNEL); + if (!cq_host->crypto_cap_array) { + err = -ENOMEM; + goto out; + } + + /* + * CCAP.CFGC is off by one, so the actual number of crypto + * configurations (a.k.a. keyslots) is CCAP.CFGC + 1. + */ + num_keyslots = cq_host->crypto_capabilities.config_count + 1; + + err = devm_blk_crypto_profile_init(dev, profile, num_keyslots); + if (err) + goto out; + + profile->ll_ops = cqhci_crypto_ops; + profile->dev = dev; + + /* Unfortunately, CQHCI crypto only supports 32 DUN bits. */ + profile->max_dun_bytes_supported = 4; + + /* + * Cache all the crypto capabilities and advertise the supported crypto + * modes and data unit sizes to the block layer. + */ + for (cap_idx = 0; cap_idx < cq_host->crypto_capabilities.num_crypto_cap; + cap_idx++) { + cq_host->crypto_cap_array[cap_idx].reg_val = + cpu_to_le32(cqhci_readl(cq_host, + CQHCI_CRYPTOCAP + + cap_idx * sizeof(__le32))); + blk_mode_num = cqhci_find_blk_crypto_mode( + cq_host->crypto_cap_array[cap_idx]); + if (blk_mode_num == BLK_ENCRYPTION_MODE_INVALID) + continue; + profile->modes_supported[blk_mode_num] |= + cq_host->crypto_cap_array[cap_idx].sdus_mask * 512; + } + + /* Clear all the keyslots so that we start in a known state. */ + for (slot = 0; slot < num_keyslots; slot++) + cqhci_crypto_clear_keyslot(cq_host, slot); + + /* CQHCI crypto requires the use of 128-bit task descriptors. */ + cq_host->caps |= CQHCI_TASK_DESC_SZ_128; + + return 0; + +out: + mmc->caps2 &= ~MMC_CAP2_CRYPTO; + return err; +} |