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  • /*
     * Copyright (c) 2015 Google, Inc
     *
     * SPDX-License-Identifier:	GPL-2.0+
     *
     * EFI information obtained here:
     * http://wiki.phoenix.com/wiki/index.php/EFI_BOOT_SERVICES
     *
     * Common EFI functions
     */
    
    #include <common.h>
    #include <debug_uart.h>
    #include <errno.h>
    #include <linux/err.h>
    #include <linux/types.h>
    #include <efi.h>
    #include <efi_api.h>
    
    DECLARE_GLOBAL_DATA_PTR;
    
    /*
     * Unfortunately we cannot access any code outside what is built especially
     * for the stub. lib/string.c is already being built for the U-Boot payload
     * so it uses the wrong compiler flags. Add our own memset() here.
     */
    static void efi_memset(void *ptr, int ch, int size)
    {
    	char *dest = ptr;
    
    	while (size-- > 0)
    		*dest++ = ch;
    }
    
    /*
     * Since the EFI stub cannot access most of the U-Boot code, add our own
     * simple console output functions here. The EFI app will not use these since
     * it can use the normal console.
     */
    void efi_putc(struct efi_priv *priv, const char ch)
    {
    	struct efi_simple_text_output_protocol *con = priv->sys_table->con_out;
    	uint16_t ucode[2];
    
    	ucode[0] = ch;
    	ucode[1] = '\0';
    	con->output_string(con, ucode);
    }
    
    void efi_puts(struct efi_priv *priv, const char *str)
    {
    	while (*str)
    		efi_putc(priv, *str++);
    }
    
    int efi_init(struct efi_priv *priv, const char *banner, efi_handle_t image,
    	     struct efi_system_table *sys_table)
    {
    	efi_guid_t loaded_image_guid = LOADED_IMAGE_PROTOCOL_GUID;
    	struct efi_boot_services *boot = sys_table->boottime;
    	struct efi_loaded_image *loaded_image;
    	int ret;
    
    	efi_memset(priv, '\0', sizeof(*priv));
    	priv->sys_table = sys_table;
    	priv->boot = sys_table->boottime;
    	priv->parent_image = image;
    	priv->run = sys_table->runtime;
    
    	efi_puts(priv, "U-Boot EFI ");
    	efi_puts(priv, banner);
    	efi_putc(priv, ' ');
    
    	ret = boot->open_protocol(priv->parent_image, &loaded_image_guid,
    				  (void **)&loaded_image, &priv->parent_image,
    				  NULL, EFI_OPEN_PROTOCOL_GET_PROTOCOL);
    	if (ret) {
    		efi_puts(priv, "Failed to get loaded image protocol\n");
    		return ret;
    	}
    	priv->image_data_type = loaded_image->image_data_type;
    
    	return 0;
    }
    
    void *efi_malloc(struct efi_priv *priv, int size, efi_status_t *retp)
    {
    	struct efi_boot_services *boot = priv->boot;
    	void *buf = NULL;
    
    	*retp = boot->allocate_pool(priv->image_data_type, size, &buf);
    
    	return buf;
    }
    
    void efi_free(struct efi_priv *priv, void *ptr)
    {
    	struct efi_boot_services *boot = priv->boot;
    
    	boot->free_pool(ptr);
    }