efi: payload: add efi-initrd for initrd install.

Install the initrd using load file2 efi protocol but keep the
ability to directly install the initrd from barebox.

Signed-off-by: Chali Anis <chalianis1@gmail.com>

Author: anischali

efi/Kconfig

@@ -41,6 +41,9 @@ config EFI_DEVICEPATH
 config EFI_FDT_FORCE
 	bool
 
+config EFI_INITRD_INSTALL
+	bool
+
 config EFI_PAYLOAD_DEFAULT_PATH
 	string
 	default "EFI/BOOT/BOOTARM.EFI"		if ARM32

efi/payload/Makefile

@@ -2,6 +2,7 @@
 
 obj-y += init.o
 obj-y += image.o
+obj-y += efi-initrd.o
 obj-$(CONFIG_OFTREE) += fdt.o
 bbenv-y += env-efi
 obj-$(CONFIG_CMD_IOMEM) += iomem.o

efi/payload/efi-initrd.c

@@ -0,0 +1,115 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <common.h>
+#include <driver.h>
+#include <init.h>
+#include <linux/hw_random.h>
+#include <efi.h>
+#include <efi/efi-device.h>
+#include <efi/device-path.h>
+#include <efi/efi-payload.h>
+
+static efi_status_t EFIAPI efi_initrd_load_file2(
+	struct efi_load_file_protocol *this, struct efi_device_path *file_path,
+	bool boot_policy, unsigned long *buffer_size, void *buffer);
+
+static const struct {
+	struct efi_device_path_vendor vendor;
+	struct efi_device_path end;
+} __packed initrd_dev_path = { { {
+					 DEVICE_PATH_TYPE_MEDIA_DEVICE,
+					 DEVICE_PATH_SUB_TYPE_VENDOR_PATH,
+					 sizeof(initrd_dev_path.vendor),
+				 },
+				 EFI_LINUX_INITRD_MEDIA_GUID },
+			       { DEVICE_PATH_TYPE_END, DEVICE_PATH_SUB_TYPE_END,
+				 DEVICE_PATH_END_LENGTH } };
+
+static struct efi_device_path_memory *initrd_dev;
+static efi_handle_t lf2_handle = NULL;
+static struct efi_load_file_protocol efi_lf2_p = {
+	.load_file = efi_initrd_load_file2
+};
+
+static efi_status_t EFIAPI efi_initrd_load_file2(
+	struct efi_load_file_protocol *this, struct efi_device_path *file_path,
+	bool boot_policy, unsigned long *buffer_size, void *buffer)
+{
+	size_t initrd_size;
+
+	pr_info("Anis here we call initrd load file2\n");
+
+	if (!this || this != &efi_lf2_p || !buffer_size)
+		return EFI_INVALID_PARAMETER;
+
+	if (file_path->type != initrd_dev_path.end.type ||
+	    file_path->sub_type != initrd_dev_path.end.sub_type)
+		return EFI_INVALID_PARAMETER;
+
+	if (boot_policy)
+		return EFI_UNSUPPORTED;
+
+	initrd_size = initrd_dev->ending_address - initrd_dev->starting_address;
+	if (!buffer || *buffer_size < initrd_size) {
+		*buffer_size = initrd_size;
+		return EFI_BUFFER_TOO_SMALL;
+	} else {
+		memcpy(buffer, (void *)(uintptr_t)initrd_dev->starting_address,
+		       initrd_size);
+		*buffer_size = initrd_size;
+	}
+
+	return EFI_SUCCESS;
+}
+
+int efi_initrd_register(void *initrd, size_t initrd_sz)
+{
+	efi_physical_addr_t mem;
+	efi_status_t efiret;
+	size_t sz;
+	int ret;
+
+	sz = sizeof(struct efi_device_path_memory) +
+	     sizeof(struct efi_device_path);
+	efiret = BS->allocate_pool(EFI_BOOT_SERVICES_DATA, sz, (void **)&mem);
+	if (EFI_ERROR(efiret)) {
+		pr_err("Failed to allocate memory for INITRD %s\n",
+		       efi_strerror(efiret));
+		ret = -efi_errno(efiret);
+		return ret;
+	}
+
+	initrd_dev = efi_phys_to_virt(mem);
+	initrd_dev->header.type = DEVICE_PATH_TYPE_HARDWARE_DEVICE;
+	initrd_dev->header.sub_type = DEVICE_PATH_SUB_TYPE_MEMORY;
+	initrd_dev->header.length = sizeof(struct efi_device_path_memory);
+	initrd_dev->memory_type = EFI_LOADER_DATA;
+	initrd_dev->starting_address = efi_virt_to_phys(initrd);
+	initrd_dev->ending_address = efi_virt_to_phys(initrd) + initrd_sz;
+
+	memcpy(&initrd_dev[1], &initrd_dev_path.end, DEVICE_PATH_END_LENGTH);
+
+	efiret = BS->install_multiple_protocol_interfaces(
+		&lf2_handle, &efi_load_file2_protocol_guid, &efi_lf2_p,
+		&efi_device_path_protocol_guid, &initrd_dev_path, NULL);
+	if (EFI_ERROR(efiret)) {
+		pr_err("Failed to install protocols for INITRD %s\n",
+		       efi_strerror(efiret));
+		ret = -efi_errno(efiret);
+		goto out;
+	}
+
+	return 0;
+out:
+	BS->free_pool(efi_phys_to_virt(mem));
+	return ret;
+}
+
+void efi_initrd_unregister()
+{
+	BS->uninstall_multiple_protocol_interfaces(
+		lf2_handle, &efi_device_path_protocol_guid, &initrd_dev_path,
+		&efi_load_file2_protocol_guid, &efi_lf2_p, NULL);
+
+	BS->free_pool(initrd_dev);
+	initrd_dev = NULL;
+}

efi/payload/image.c

@@ -467,16 +467,24 @@ static int efi_load_ramdisk(struct efi_image_data *e)
 	}
 
 	memcpy(vmem, (void *)initrd, initrd_size);
-
 	e->initrd_res->base = (uint64_t)mem;
 	e->initrd_res->size = (uint64_t)initrd_size;
-	
-	efiret = BS->install_configuration_table(&efi_linux_initrd_media_guid, 
-	(void *)e->initrd_res);
-	if (EFI_ERROR(efiret)) {
-		ret = -efi_errno(efiret);
-		pr_err("Failed to install INITRD %s/n", efi_strerror(efiret));
-		goto free_pages;
+
+	if (IS_ENABLED(CONFIG_EFI_INITRD_INSTALL)) {
+		efiret = BS->install_configuration_table(&efi_linux_initrd_media_guid, 
+		(void *)e->initrd_res);
+		if (EFI_ERROR(efiret)) {
+			ret = -efi_errno(efiret);
+			pr_err("Failed to install INITRD %s/n", efi_strerror(efiret));
+			goto free_pages;
+		}
+	}
+	else {
+		ret = efi_initrd_register(vmem, initrd_size);
+		if (ret) {
+			pr_err("Failed to register INITRD %s/n", strerror(efiret));
+			goto free_pages;
+		}
 	}
 
 	if (!from_fit && tmp)
@@ -496,7 +504,11 @@ static int efi_load_ramdisk(struct efi_image_data *e)
 }
 
 static void efi_unload_ramdisk(struct efi_image_data *e) {
-	BS->install_configuration_table(&efi_linux_initrd_media_guid, NULL);
+	
+	if (IS_ENABLED(CONFIG_EFI_INITRD_INSTALL)) 
+		BS->install_configuration_table(&efi_linux_initrd_media_guid, NULL);
+	else
+		efi_initrd_unregister();
 
 	efi_free_pages(efi_phys_to_virt(e->initrd_res->base),
 				 e->initrd_res->size);

include/efi/efi-payload.h

@@ -34,4 +34,7 @@ int efi_set_variable_usec(char *name, efi_guid_t *vendor, uint64_t usec);
 void *efi_earlymem_alloc(const struct efi_system_table *sys_table,
 			 size_t *memsize, enum efi_memory_type mem_type);
 
+int efi_initrd_register(void *initrd, size_t initrd_size);
+void efi_initrd_unregister(void);
+
 #endif