text: // SPDX-License-Identifier: GPL-2.0+
  /*
   * (C) Copyright 2015 Miao Yan <yanmiaobest@gmail.com>
   */
  
  #include <common.h>
  #include <command.h>
  #include <errno.h>
  #include <malloc.h>
  #include <qfw.h>
  #include <asm/io.h>
  #ifdef CONFIG_GENERATE_ACPI_TABLE
  #include <asm/tables.h>
  #endif
  #include <linux/list.h>
  
  static bool fwcfg_present;
  static bool fwcfg_dma_present;
  static struct fw_cfg_arch_ops *fwcfg_arch_ops;
  
  static LIST_HEAD(fw_list);
  
  #ifdef CONFIG_GENERATE_ACPI_TABLE
  /*
   * This function allocates memory for ACPI tables
   *
   * @entry : BIOS linker command entry which tells where to allocate memory
   *          (either high memory or low memory)
   * @addr  : The address that should be used for low memory allcation. If the
   *          memory allocation request is 'ZONE_HIGH' then this parameter will
   *          be ignored.
   * @return: 0 on success, or negative value on failure
   */
  static int bios_linker_allocate(struct bios_linker_entry *entry, ulong *addr)
  {
  	uint32_t size, align;
  	struct fw_file *file;
  	unsigned long aligned_addr;
  
  	align = le32_to_cpu(entry->alloc.align);
  	/* align must be power of 2 */
  	if (align & (align - 1)) {
  		printf("error: wrong alignment %u\n", align);
  		return -EINVAL;
  	}
  
  	file = qemu_fwcfg_find_file(entry->alloc.file);
  	if (!file) {
  		printf("error: can't find file %s\n", entry->alloc.file);
  		return -ENOENT;
  	}
  
  	size = be32_to_cpu(file->cfg.size);
  
  	/*
  	 * ZONE_HIGH means we need to allocate from high memory, since
  	 * malloc space is already at the end of RAM, so we directly use it.
  	 * If allocation zone is ZONE_FSEG, then we use the 'addr' passed
  	 * in which is low memory
  	 */
  	if (entry->alloc.zone == BIOS_LINKER_LOADER_ALLOC_ZONE_HIGH) {
  		aligned_addr = (unsigned long)memalign(align, size);
  		if (!aligned_addr) {
  			printf("error: allocating resource\n");
  			return -ENOMEM;
  		}
  	} else if (entry->alloc.zone == BIOS_LINKER_LOADER_ALLOC_ZONE_FSEG) {
  		aligned_addr = ALIGN(*addr, align);
  	} else {
  		printf("error: invalid allocation zone\n");
  		return -EINVAL;
  	}
  
  	debug("bios_linker_allocate: allocate file %s, size %u, zone %d, align %u, addr 0x%lx\n",
  	      file->cfg.name, size, entry->alloc.zone, align, aligned_addr);
  
  	qemu_fwcfg_read_entry(be16_to_cpu(file->cfg.select),
  			      size, (void *)aligned_addr);
  	file->addr = aligned_addr;
  
  	/* adjust address for low memory allocation */
  	if (entry->alloc.zone == BIOS_LINKER_LOADER_ALLOC_ZONE_FSEG)
  		*addr = (aligned_addr + size);
  
  	return 0;
  }
  
  /*
   * This function patches ACPI tables previously loaded
   * by bios_linker_allocate()
   *
   * @entry : BIOS linker command entry which tells how to patch
   *          ACPI tables
   * @return: 0 on success, or negative value on failure
   */
  static int bios_linker_add_pointer(struct bios_linker_entry *entry)
  {
  	struct fw_file *dest, *src;
  	uint32_t offset = le32_to_cpu(entry->pointer.offset);
  	uint64_t pointer = 0;
  
  	dest = qemu_fwcfg_find_file(entry->pointer.dest_file);
  	if (!dest || !dest->addr)
  		return -ENOENT;
  	src = qemu_fwcfg_find_file(entry->pointer.src_file);
  	if (!src || !src->addr)
  		return -ENOENT;
  
  	debug("bios_linker_add_pointer: dest->addr 0x%lx, src->addr 0x%lx, offset 0x%x size %u, 0x%llx\n",
  	      dest->addr, src->addr, offset, entry->pointer.size, pointer);
  
  	memcpy(&pointer, (char *)dest->addr + offset, entry->pointer.size);
  	pointer	= le64_to_cpu(pointer);
  	pointer += (unsigned long)src->addr;
  	pointer	= cpu_to_le64(pointer);
  	memcpy((char *)dest->addr + offset, &pointer, entry->pointer.size);
  
  	return 0;
  }
  
  /*
   * This function updates checksum fields of ACPI tables previously loaded
   * by bios_linker_allocate()
   *
   * @entry : BIOS linker command entry which tells where to update ACPI table
   *          checksums
   * @return: 0 on success, or negative value on failure
   */
  static int bios_linker_add_checksum(struct bios_linker_entry *entry)
  {
  	struct fw_file *file;
  	uint8_t *data, cksum = 0;
  	uint8_t *cksum_start;
  
  	file = qemu_fwcfg_find_file(entry->cksum.file);
  	if (!file || !file->addr)
  		return -ENOENT;
  
  	data = (uint8_t *)(file->addr + le32_to_cpu(entry->cksum.offset));
  	cksum_start = (uint8_t *)(file->addr + le32_to_cpu(entry->cksum.start));
  	cksum = table_compute_checksum(cksum_start,
  				       le32_to_cpu(entry->cksum.length));
  	*data = cksum;
  
  	return 0;
  }
  
  /* This function loads and patches ACPI tables provided by QEMU */
  ulong write_acpi_tables(ulong addr)
  {
  	int i, ret = 0;
  	struct fw_file *file;
  	struct bios_linker_entry *table_loader;
  	struct bios_linker_entry *entry;
  	uint32_t size;
  
  	/* make sure fw_list is loaded */
  	ret = qemu_fwcfg_read_firmware_list();
  	if (ret) {
  		printf("error: can't read firmware file list\n");
  		return addr;
  	}
  
  	file = qemu_fwcfg_find_file("etc/table-loader");
  	if (!file) {
  		printf("error: can't find etc/table-loader\n");
  		return addr;
  	}
  
  	size = be32_to_cpu(file->cfg.size);
  	if ((size % sizeof(*entry)) != 0) {
  		printf("error: table-loader maybe corrupted\n");
  		return addr;
  	}
  
  	table_loader = malloc(size);
  	if (!table_loader) {
  		printf("error: no memory for table-loader\n");
  		return addr;
  	}
  
  	qemu_fwcfg_read_entry(be16_to_cpu(file->cfg.select),
  			      size, table_loader);
  
  	for (i = 0; i < (size / sizeof(*entry)); i++) {
  		entry = table_loader + i;
  		switch (le32_to_cpu(entry->command)) {
  		case BIOS_LINKER_LOADER_COMMAND_ALLOCATE:
  			ret = bios_linker_allocate(entry, &addr);
  			if (ret)
  				goto out;
  			break;
  		case BIOS_LINKER_LOADER_COMMAND_ADD_POINTER:
  			ret = bios_linker_add_pointer(entry);
  			if (ret)
  				goto out;
  			break;
  		case BIOS_LINKER_LOADER_COMMAND_ADD_CHECKSUM:
  			ret = bios_linker_add_checksum(entry);
  			if (ret)
  				goto out;
  			break;
  		default:
  			break;
  		}
  	}
  
  out:
  	if (ret) {
  		struct fw_cfg_file_iter iter;
  		for (file = qemu_fwcfg_file_iter_init(&iter);
  		     !qemu_fwcfg_file_iter_end(&iter);
  		     file = qemu_fwcfg_file_iter_next(&iter)) {
  			if (file->addr) {
  				free((void *)file->addr);
  				file->addr = 0;
  			}
  		}
  	}
  
  	free(table_loader);
  	return addr;
  }
  
  ulong acpi_get_rsdp_addr(void)
  {
  	struct fw_file *file;
  
  	file = qemu_fwcfg_find_file("etc/acpi/rsdp");
  	return file->addr;
  }
  #endif
  
  /* Read configuration item using fw_cfg PIO interface */
  static void qemu_fwcfg_read_entry_pio(uint16_t entry,
  		uint32_t size, void *address)
  {
  	debug("qemu_fwcfg_read_entry_pio: entry 0x%x, size %u address %p\n",
  	      entry, size, address);
  
  	return fwcfg_arch_ops->arch_read_pio(entry, size, address);
  }
  
  /* Read configuration item using fw_cfg DMA interface */
  static void qemu_fwcfg_read_entry_dma(uint16_t entry,
  		uint32_t size, void *address)
  {
  	struct fw_cfg_dma_access dma;
  
  	dma.length = cpu_to_be32(size);
  	dma.address = cpu_to_be64((uintptr_t)address);
  	dma.control = cpu_to_be32(FW_CFG_DMA_READ);
  
  	/*
  	 * writting FW_CFG_INVALID will cause read operation to resume at
  	 * last offset, otherwise read will start at offset 0
  	 */
  	if (entry != FW_CFG_INVALID)
  		dma.control |= cpu_to_be32(FW_CFG_DMA_SELECT | (entry << 16));
  
  	barrier();
  
  	debug("qemu_fwcfg_read_entry_dma: entry 0x%x, size %u address %p, control 0x%x\n",
  	      entry, size, address, be32_to_cpu(dma.control));
  
  	fwcfg_arch_ops->arch_read_dma(&dma);
  }
  
  bool qemu_fwcfg_present(void)
  {
  	return fwcfg_present;
  }
  
  bool qemu_fwcfg_dma_present(void)
  {
  	return fwcfg_dma_present;
  }
  
  void qemu_fwcfg_read_entry(uint16_t entry, uint32_t length, void *address)
  {
  	if (fwcfg_dma_present)
  		qemu_fwcfg_read_entry_dma(entry, length, address);
  	else
  		qemu_fwcfg_read_entry_pio(entry, length, address);
  }
  
  int qemu_fwcfg_online_cpus(void)
  {
  	uint16_t nb_cpus;
  
  	if (!fwcfg_present)
  		return -ENODEV;
  
  	qemu_fwcfg_read_entry(FW_CFG_NB_CPUS, 2, &nb_cpus);
  
  	return le16_to_cpu(nb_cpus);
  }
  
  int qemu_fwcfg_read_firmware_list(void)
  {
  	int i;
  	uint32_t count;
  	struct fw_file *file;
  	struct list_head *entry;
  
  	/* don't read it twice */
  	if (!list_empty(&fw_list))
  		return 0;
  
  	qemu_fwcfg_read_entry(FW_CFG_FILE_DIR, 4, &count);
  	if (!count)
  		return 0;
  
  	count = be32_to_cpu(count);
  	for (i = 0; i < count; i++) {
  		file = malloc(sizeof(*file));
  		if (!file) {
  			printf("error: allocating resource\n");
  			goto err;
  		}
  		qemu_fwcfg_read_entry(FW_CFG_INVALID,
  				      sizeof(struct fw_cfg_file), &file->cfg);
  		file->addr = 0;
  		list_add_tail(&file->list, &fw_list);
  	}
  
  	return 0;
  
  err:
  	list_for_each(entry, &fw_list) {
  		file = list_entry(entry, struct fw_file, list);
  		free(file);
  	}
  
  	return -ENOMEM;
  }
  
  struct fw_file *qemu_fwcfg_find_file(const char *name)
  {
  	struct list_head *entry;
  	struct fw_file *file;
  
  	list_for_each(entry, &fw_list) {
  		file = list_entry(entry, struct fw_file, list);
  		if (!strcmp(file->cfg.name, name))
  			return file;
  	}
  
  	return NULL;
  }
  
  struct fw_file *qemu_fwcfg_file_iter_init(struct fw_cfg_file_iter *iter)
  {
  	iter->entry = fw_list.next;
  	return list_entry((struct list_head *)iter->entry,
  			  struct fw_file, list);
  }
  
  struct fw_file *qemu_fwcfg_file_iter_next(struct fw_cfg_file_iter *iter)
  {
  	iter->entry = ((struct list_head *)iter->entry)->next;
  	return list_entry((struct list_head *)iter->entry,
  			  struct fw_file, list);
  }
  
  bool qemu_fwcfg_file_iter_end(struct fw_cfg_file_iter *iter)
  {
  	return iter->entry == &fw_list;
  }
  
  void qemu_fwcfg_init(struct fw_cfg_arch_ops *ops)
  {
  	uint32_t qemu;
  	uint32_t dma_enabled;
  
  	fwcfg_present = false;
  	fwcfg_dma_present = false;
  	fwcfg_arch_ops = NULL;
  
  	if (!ops || !ops->arch_read_pio || !ops->arch_read_dma)
  		return;
  	fwcfg_arch_ops = ops;
  
  	qemu_fwcfg_read_entry_pio(FW_CFG_SIGNATURE, 4, &qemu);
  	if (be32_to_cpu(qemu) == QEMU_FW_CFG_SIGNATURE)
  		fwcfg_present = true;
  
  	if (fwcfg_present) {
  		qemu_fwcfg_read_entry_pio(FW_CFG_ID, 1, &dma_enabled);
  		if (dma_enabled & FW_CFG_DMA_ENABLED)
  			fwcfg_dma_present = true;
  	}
  }
  