1 files changed, 50 insertions, 68 deletions

diff --git a/drivers/firmware/efi/libstub/efi-stub.c b/drivers/firmware/efi/libstub/efi-stub.c
index f515394cce6e..cf474f0dd261 100644
--- a/drivers/firmware/efi/libstub/efi-stub.c
+++ b/drivers/firmware/efi/libstub/efi-stub.c
@@ -10,7 +10,6 @@
  */
 
 #include <linux/efi.h>
-#include <linux/libfdt.h>
 #include <asm/efi.h>
 
 #include "efistub.h"
@@ -40,16 +39,22 @@
 
 #ifdef CONFIG_ARM64
 # define EFI_RT_VIRTUAL_LIMIT	DEFAULT_MAP_WINDOW_64
-#elif defined(CONFIG_RISCV)
+#elif defined(CONFIG_RISCV) || defined(CONFIG_LOONGARCH)
 # define EFI_RT_VIRTUAL_LIMIT	TASK_SIZE_MIN
-#else
+#else /* Only if TASK_SIZE is a constant */
 # define EFI_RT_VIRTUAL_LIMIT	TASK_SIZE
 #endif
 
-static u64 virtmap_base = EFI_RT_VIRTUAL_BASE;
-static bool flat_va_mapping;
+/*
+ * Some architectures map the EFI regions into the kernel's linear map using a
+ * fixed offset.
+ */
+#ifndef EFI_RT_VIRTUAL_OFFSET
+#define EFI_RT_VIRTUAL_OFFSET	0
+#endif
 
-const efi_system_table_t *efi_system_table;
+static u64 virtmap_base = EFI_RT_VIRTUAL_BASE;
+static bool flat_va_mapping = (EFI_RT_VIRTUAL_OFFSET != 0);
 
 static struct screen_info *setup_graphics(void)
 {
@@ -124,16 +129,11 @@ efi_status_t __efiapi efi_pe_entry(efi_handle_t handle,
 	unsigned long image_addr;
 	unsigned long image_size = 0;
 	/* addr/point and size pairs for memory management*/
-	unsigned long initrd_addr = 0;
-	unsigned long initrd_size = 0;
-	unsigned long fdt_addr = 0;  /* Original DTB */
-	unsigned long fdt_size = 0;
 	char *cmdline_ptr = NULL;
 	int cmdline_size = 0;
 	efi_guid_t loaded_image_proto = LOADED_IMAGE_PROTOCOL_GUID;
 	unsigned long reserve_addr = 0;
 	unsigned long reserve_size = 0;
-	enum efi_secureboot_mode secure_boot;
 	struct screen_info *si;
 	efi_properties_table_t *prop_tbl;
 
@@ -154,8 +154,8 @@ efi_status_t __efiapi efi_pe_entry(efi_handle_t handle,
 	 * information about the running image, such as size and the command
 	 * line.
 	 */
-	status = efi_system_table->boottime->handle_protocol(handle,
-					&loaded_image_proto, (void *)&image);
+	status = efi_bs_call(handle_protocol, handle, &loaded_image_proto,
+			     (void *)&image);
 	if (status != EFI_SUCCESS) {
 		efi_err("Failed to get loaded image protocol\n");
 		goto fail;
@@ -209,40 +209,8 @@ efi_status_t __efiapi efi_pe_entry(efi_handle_t handle,
 	/* Ask the firmware to clear memory on unclean shutdown */
 	efi_enable_reset_attack_mitigation();
 
-	secure_boot = efi_get_secureboot();
-
-	/*
-	 * Unauthenticated device tree data is a security hazard, so ignore
-	 * 'dtb=' unless UEFI Secure Boot is disabled.  We assume that secure
-	 * boot is enabled if we can't determine its state.
-	 */
-	if (!IS_ENABLED(CONFIG_EFI_ARMSTUB_DTB_LOADER) ||
-	     secure_boot != efi_secureboot_mode_disabled) {
-		if (strstr(cmdline_ptr, "dtb="))
-			efi_err("Ignoring DTB from command line.\n");
-	} else {
-		status = efi_load_dtb(image, &fdt_addr, &fdt_size);
-
-		if (status != EFI_SUCCESS) {
-			efi_err("Failed to load device tree!\n");
-			goto fail_free_image;
-		}
-	}
-
-	if (fdt_addr) {
-		efi_info("Using DTB from command line\n");
-	} else {
-		/* Look for a device tree configuration table entry. */
-		fdt_addr = (uintptr_t)get_fdt(&fdt_size);
-		if (fdt_addr)
-			efi_info("Using DTB from configuration table\n");
-	}
-
-	if (!fdt_addr)
-		efi_info("Generating empty DTB\n");
-
-	efi_load_initrd(image, &initrd_addr, &initrd_size, ULONG_MAX,
-			efi_get_max_initrd_addr(image_addr));
+	efi_load_initrd(image, ULONG_MAX, efi_get_max_initrd_addr(image_addr),
+			NULL);
 
 	efi_random_get_seed();
 
@@ -254,8 +222,8 @@ efi_status_t __efiapi efi_pe_entry(efi_handle_t handle,
 	 * The easiest way to achieve that is to simply use a 1:1 mapping.
 	 */
 	prop_tbl = get_efi_config_table(EFI_PROPERTIES_TABLE_GUID);
-	flat_va_mapping = prop_tbl &&
-			  (prop_tbl->memory_protection_attribute &
+	flat_va_mapping |= prop_tbl &&
+			   (prop_tbl->memory_protection_attribute &
 			   EFI_PROPERTIES_RUNTIME_MEMORY_PROTECTION_NON_EXECUTABLE_PE_DATA);
 
 	/* force efi_novamap if SetVirtualAddressMap() is unsupported */
@@ -284,25 +252,8 @@ efi_status_t __efiapi efi_pe_entry(efi_handle_t handle,
 
 	install_memreserve_table();
 
-	status = allocate_new_fdt_and_exit_boot(handle, &fdt_addr,
-						initrd_addr, initrd_size,
-						cmdline_ptr, fdt_addr, fdt_size);
-	if (status != EFI_SUCCESS)
-		goto fail_free_initrd;
-
-	if (IS_ENABLED(CONFIG_ARM))
-		efi_handle_post_ebs_state();
-
-	efi_enter_kernel(image_addr, fdt_addr, fdt_totalsize((void *)fdt_addr));
-	/* not reached */
-
-fail_free_initrd:
-	efi_err("Failed to update FDT and exit boot services\n");
+	status = efi_boot_kernel(handle, image, image_addr, cmdline_ptr);
 
-	efi_free(initrd_size, initrd_addr);
-	efi_free(fdt_size, fdt_addr);
-
-fail_free_image:
 	efi_free(image_size, image_addr);
 	efi_free(reserve_size, reserve_addr);
 fail_free_screeninfo:
@@ -314,6 +265,35 @@ fail:
 }
 
 /*
+ * efi_allocate_virtmap() - create a pool allocation for the virtmap
+ *
+ * Create an allocation that is of sufficient size to hold all the memory
+ * descriptors that will be passed to SetVirtualAddressMap() to inform the
+ * firmware about the virtual mapping that will be used under the OS to call
+ * into the firmware.
+ */
+efi_status_t efi_alloc_virtmap(efi_memory_desc_t **virtmap,
+			       unsigned long *desc_size, u32 *desc_ver)
+{
+	unsigned long size, mmap_key;
+	efi_status_t status;
+
+	/*
+	 * Use the size of the current memory map as an upper bound for the
+	 * size of the buffer we need to pass to SetVirtualAddressMap() to
+	 * cover all EFI_MEMORY_RUNTIME regions.
+	 */
+	size = 0;
+	status = efi_bs_call(get_memory_map, &size, NULL, &mmap_key, desc_size,
+			     desc_ver);
+	if (status != EFI_BUFFER_TOO_SMALL)
+		return EFI_LOAD_ERROR;
+
+	return efi_bs_call(allocate_pool, EFI_LOADER_DATA, size,
+			   (void **)virtmap);
+}
+
+/*
  * efi_get_virtmap() - create a virtual mapping for the EFI memory map
  *
  * This function populates the virt_addr fields of all memory region descriptors
@@ -328,6 +308,8 @@ void efi_get_virtmap(efi_memory_desc_t *memory_map, unsigned long map_size,
 	efi_memory_desc_t *in, *out = runtime_map;
 	int l;
 
+	*count = 0;
+
 	for (l = 0; l < map_size; l += desc_size) {
 		u64 paddr, size;
 
@@ -338,7 +320,7 @@ void efi_get_virtmap(efi_memory_desc_t *memory_map, unsigned long map_size,
 		paddr = in->phys_addr;
 		size = in->num_pages * EFI_PAGE_SIZE;
 
-		in->virt_addr = in->phys_addr;
+		in->virt_addr = in->phys_addr + EFI_RT_VIRTUAL_OFFSET;
 		if (efi_novamap) {
 			continue;
 		}