// SPDX-License-Identifier: GPL-2.0 /* * NVM helpers * * Copyright (C) 2020, Intel Corporation * Author: Mika Westerberg */ #include #include #include #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); } /** * tb_nvm_read_data() - Read data from NVM * @address: Start address on the flash * @buf: Buffer where the read data is copied * @size: Size of the buffer in bytes * @retries: Number of retries if block read fails * @read_block: Function that reads block from the flash * @read_block_data: Data passsed to @read_block * * This is a generic function that reads data from NVM or NVM like * device. * * Returns %0 on success and negative errno otherwise. */ int tb_nvm_read_data(unsigned int address, void *buf, size_t size, unsigned int retries, read_block_fn read_block, void *read_block_data) { do { unsigned int dwaddress, dwords, offset; u8 data[NVM_DATA_DWORDS * 4]; size_t nbytes; int ret; offset = address & 3; nbytes = min_t(size_t, size + offset, NVM_DATA_DWORDS * 4); dwaddress = address / 4; dwords = ALIGN(nbytes, 4) / 4; ret = read_block(read_block_data, dwaddress, data, dwords); if (ret) { if (ret != -ENODEV && retries--) continue; return ret; } nbytes -= offset; memcpy(buf, data + offset, nbytes); size -= nbytes; address += nbytes; buf += nbytes; } while (size > 0); return 0; } /** * tb_nvm_write_data() - Write data to NVM * @address: Start address on the flash * @buf: Buffer where the data is copied from * @size: Size of the buffer in bytes * @retries: Number of retries if the block write fails * @write_block: Function that writes block to the flash * @write_block_data: Data passwd to @write_block * * This is generic function that writes data to NVM or NVM like device. * * Returns %0 on success and negative errno otherwise. */ int tb_nvm_write_data(unsigned int address, const void *buf, size_t size, unsigned int retries, write_block_fn write_block, void *write_block_data) { do { unsigned int offset, dwaddress; u8 data[NVM_DATA_DWORDS * 4]; size_t nbytes; int ret; offset = address & 3; nbytes = min_t(u32, size + offset, NVM_DATA_DWORDS * 4); memcpy(data + offset, buf, nbytes); dwaddress = address / 4; ret = write_block(write_block_data, dwaddress, data, nbytes / 4); if (ret) { if (ret == -ETIMEDOUT) { if (retries--) continue; ret = -EIO; } return ret; } size -= nbytes; address += nbytes; buf += nbytes; } while (size > 0); return 0; } void tb_nvm_exit(void) { ida_destroy(&nvm_ida); }