diff options
Diffstat (limited to 'drivers/thunderbolt/nvm.c')
| -rw-r--r-- | drivers/thunderbolt/nvm.c | 170 |
1 files changed, 170 insertions, 0 deletions
diff --git a/drivers/thunderbolt/nvm.c b/drivers/thunderbolt/nvm.c new file mode 100644 index 000000000000..29de6d95c6e7 --- /dev/null +++ b/drivers/thunderbolt/nvm.c @@ -0,0 +1,170 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * NVM helpers + * + * Copyright (C) 2020, Intel Corporation + * Author: Mika Westerberg <mika.westerberg@linux.intel.com> + */ + +#include <linux/idr.h> +#include <linux/slab.h> +#include <linux/vmalloc.h> + +#include "tb.h" + +static DEFINE_IDA(nvm_ida); + +/** + * tb_nvm_alloc() - Allocate new NVM structure + * @dev: Device owning the NVM + * + * Allocates new NVM structure with unique @id and returns it. In case + * of error returns ERR_PTR(). + */ +struct tb_nvm *tb_nvm_alloc(struct device *dev) +{ + struct tb_nvm *nvm; + int ret; + + nvm = kzalloc(sizeof(*nvm), GFP_KERNEL); + if (!nvm) + return ERR_PTR(-ENOMEM); + + ret = ida_simple_get(&nvm_ida, 0, 0, GFP_KERNEL); + if (ret < 0) { + kfree(nvm); + return ERR_PTR(ret); + } + + nvm->id = ret; + nvm->dev = dev; + + return nvm; +} + +/** + * tb_nvm_add_active() - Adds active NVMem device to NVM + * @nvm: NVM structure + * @size: Size of the active NVM in bytes + * @reg_read: Pointer to the function to read the NVM (passed directly to the + * NVMem device) + * + * Registers new active NVmem device for @nvm. The @reg_read is called + * directly from NVMem so it must handle possible concurrent access if + * needed. The first parameter passed to @reg_read is @nvm structure. + * Returns %0 in success and negative errno otherwise. + */ +int tb_nvm_add_active(struct tb_nvm *nvm, size_t size, nvmem_reg_read_t reg_read) +{ + struct nvmem_config config; + struct nvmem_device *nvmem; + + memset(&config, 0, sizeof(config)); + + config.name = "nvm_active"; + config.reg_read = reg_read; + config.read_only = true; + config.id = nvm->id; + config.stride = 4; + config.word_size = 4; + config.size = size; + config.dev = nvm->dev; + config.owner = THIS_MODULE; + config.priv = nvm; + + nvmem = nvmem_register(&config); + if (IS_ERR(nvmem)) + return PTR_ERR(nvmem); + + nvm->active = nvmem; + return 0; +} + +/** + * tb_nvm_write_buf() - Write data to @nvm buffer + * @nvm: NVM structure + * @offset: Offset where to write the data + * @val: Data buffer to write + * @bytes: Number of bytes to write + * + * Helper function to cache the new NVM image before it is actually + * written to the flash. Copies @bytes from @val to @nvm->buf starting + * from @offset. + */ +int tb_nvm_write_buf(struct tb_nvm *nvm, unsigned int offset, void *val, + size_t bytes) +{ + if (!nvm->buf) { + nvm->buf = vmalloc(NVM_MAX_SIZE); + if (!nvm->buf) + return -ENOMEM; + } + + nvm->flushed = false; + nvm->buf_data_size = offset + bytes; + memcpy(nvm->buf + offset, val, bytes); + return 0; +} + +/** + * tb_nvm_add_non_active() - Adds non-active NVMem device to NVM + * @nvm: NVM structure + * @size: Size of the non-active NVM in bytes + * @reg_write: Pointer to the function to write the NVM (passed directly + * to the NVMem device) + * + * Registers new non-active NVmem device for @nvm. The @reg_write is called + * directly from NVMem so it must handle possible concurrent access if + * needed. The first parameter passed to @reg_write is @nvm structure. + * Returns %0 in success and negative errno otherwise. + */ +int tb_nvm_add_non_active(struct tb_nvm *nvm, size_t size, + nvmem_reg_write_t reg_write) +{ + struct nvmem_config config; + struct nvmem_device *nvmem; + + memset(&config, 0, sizeof(config)); + + config.name = "nvm_non_active"; + config.reg_write = reg_write; + config.root_only = true; + config.id = nvm->id; + config.stride = 4; + config.word_size = 4; + config.size = size; + config.dev = nvm->dev; + config.owner = THIS_MODULE; + config.priv = nvm; + + nvmem = nvmem_register(&config); + if (IS_ERR(nvmem)) + return PTR_ERR(nvmem); + + nvm->non_active = nvmem; + return 0; +} + +/** + * tb_nvm_free() - Release NVM and its resources + * @nvm: NVM structure to release + * + * Releases NVM and the NVMem devices if they were registered. + */ +void tb_nvm_free(struct tb_nvm *nvm) +{ + if (nvm) { + if (nvm->non_active) + nvmem_unregister(nvm->non_active); + if (nvm->active) + nvmem_unregister(nvm->active); + vfree(nvm->buf); + ida_simple_remove(&nvm_ida, nvm->id); + } + kfree(nvm); +} + +void tb_nvm_exit(void) +{ + ida_destroy(&nvm_ida); +} |