return 0;
 }
 
-static int __init efi_runtime_init(void)
+static int __init efi_runtime_init32(void)
 {
-       efi_runtime_services_t *runtime;
+       efi_runtime_services_32_t *runtime;
+
+       runtime = early_ioremap((unsigned long)efi.systab->runtime,
+                       sizeof(efi_runtime_services_32_t));
+       if (!runtime) {
+               pr_err("Could not map the runtime service table!\n");
+               return -ENOMEM;
+       }
 
        /*
-        * Check out the runtime services table. We need to map
-        * the runtime services table so that we can grab the physical
-        * address of several of the EFI runtime functions, needed to
-        * set the firmware into virtual mode.
+        * We will only need *early* access to the following two
+        * EFI runtime services before set_virtual_address_map
+        * is invoked.
         */
+       efi_phys.get_time = (efi_get_time_t *)
+                       (unsigned long)runtime->get_time;
+       efi_phys.set_virtual_address_map =
+                       (efi_set_virtual_address_map_t *)
+                       (unsigned long)runtime->set_virtual_address_map;
+       /*
+        * Make efi_get_time can be called before entering
+        * virtual mode.
+        */
+       efi.get_time = phys_efi_get_time;
+       early_iounmap(runtime, sizeof(efi_runtime_services_32_t));
+
+       return 0;
+}
+
+static int __init efi_runtime_init64(void)
+{
+       efi_runtime_services_64_t *runtime;
+
        runtime = early_ioremap((unsigned long)efi.systab->runtime,
-                               sizeof(efi_runtime_services_t));
+                       sizeof(efi_runtime_services_64_t));
        if (!runtime) {
                pr_err("Could not map the runtime service table!\n");
                return -ENOMEM;
        }
+
        /*
-        * We will only need *early* access to the following
-        * two EFI runtime services before set_virtual_address_map
+        * We will only need *early* access to the following two
+        * EFI runtime services before set_virtual_address_map
         * is invoked.
         */
-       efi_phys.get_time = (efi_get_time_t *)runtime->get_time;
+       efi_phys.get_time = (efi_get_time_t *)
+                       (unsigned long)runtime->get_time;
        efi_phys.set_virtual_address_map =
-               (efi_set_virtual_address_map_t *)
-               runtime->set_virtual_address_map;
+                       (efi_set_virtual_address_map_t *)
+                       (unsigned long)runtime->set_virtual_address_map;
        /*
         * Make efi_get_time can be called before entering
         * virtual mode.
         */
        efi.get_time = phys_efi_get_time;
-       early_iounmap(runtime, sizeof(efi_runtime_services_t));
+       early_iounmap(runtime, sizeof(efi_runtime_services_64_t));
+
+       return 0;
+}
+
+static int __init efi_runtime_init(void)
+{
+       int rv;
+
+       /*
+        * Check out the runtime services table. We need to map
+        * the runtime services table so that we can grab the physical
+        * address of several of the EFI runtime functions, needed to
+        * set the firmware into virtual mode.
+        */
+       if (efi_enabled(EFI_64BIT))
+               rv = efi_runtime_init64();
+       else
+               rv = efi_runtime_init32();
+
+       if (rv)
+               return rv;
 
        return 0;
 }
                       (unsigned long long)md->phys_addr);
 }
 
+static void native_runtime_setup(void)
+{
+       efi.get_time = virt_efi_get_time;
+       efi.set_time = virt_efi_set_time;
+       efi.get_wakeup_time = virt_efi_get_wakeup_time;
+       efi.set_wakeup_time = virt_efi_set_wakeup_time;
+       efi.get_variable = virt_efi_get_variable;
+       efi.get_next_variable = virt_efi_get_next_variable;
+       efi.set_variable = virt_efi_set_variable;
+       efi.get_next_high_mono_count = virt_efi_get_next_high_mono_count;
+       efi.reset_system = virt_efi_reset_system;
+       efi.query_variable_info = virt_efi_query_variable_info;
+       efi.update_capsule = virt_efi_update_capsule;
+       efi.query_capsule_caps = virt_efi_query_capsule_caps;
+}
+
 /* Merge contiguous regions of the same type and attribute */
 static void __init efi_merge_regions(void)
 {
        efi_sync_low_kernel_mappings();
 
        if (!efi_setup) {
-               status = phys_efi_set_virtual_address_map(
-                       memmap.desc_size * count,
-                       memmap.desc_size,
-                       memmap.desc_version,
-                       (efi_memory_desc_t *)__pa(new_memmap));
+               if (efi_is_native()) {
+                       status = phys_efi_set_virtual_address_map(
+                                       memmap.desc_size * count,
+                                       memmap.desc_size,
+                                       memmap.desc_version,
+                                       (efi_memory_desc_t *)__pa(new_memmap));
+               } else {
+                       status = efi_thunk_set_virtual_address_map(
+                                       efi_phys.set_virtual_address_map,
+                                       memmap.desc_size * count,
+                                       memmap.desc_size,
+                                       memmap.desc_version,
+                                       (efi_memory_desc_t *)__pa(new_memmap));
+               }
 
                if (status != EFI_SUCCESS) {
                        pr_alert("Unable to switch EFI into virtual mode (status=%lx)!\n",
         * Call EFI services through wrapper functions.
         */
        efi.runtime_version = efi_systab.hdr.revision;
-       efi.get_time = virt_efi_get_time;
-       efi.set_time = virt_efi_set_time;
-       efi.get_wakeup_time = virt_efi_get_wakeup_time;
-       efi.set_wakeup_time = virt_efi_set_wakeup_time;
-       efi.get_variable = virt_efi_get_variable;
-       efi.get_next_variable = virt_efi_get_next_variable;
-       efi.set_variable = virt_efi_set_variable;
-       efi.get_next_high_mono_count = virt_efi_get_next_high_mono_count;
-       efi.reset_system = virt_efi_reset_system;
+
+       if (efi_is_native())
+               native_runtime_setup();
+       else
+               efi_thunk_runtime_setup();
+
        efi.set_virtual_address_map = NULL;
-       efi.query_variable_info = virt_efi_query_variable_info;
-       efi.update_capsule = virt_efi_update_capsule;
-       efi.query_capsule_caps = virt_efi_query_capsule_caps;
 
        efi_runtime_mkexec();
 
 
 #include <asm/cacheflush.h>
 #include <asm/fixmap.h>
 #include <asm/realmode.h>
+#include <asm/time.h>
 
 static pgd_t *save_pgd __initdata;
 static unsigned long efi_flags __initdata;
        u64 prev_cr3;
        pgd_t *efi_pgt;
        bool use_pgd;
-};
+       u64 phys_stack;
+} __packed;
 
 static void __init early_code_mapping_set_exec(int executable)
 {
 
 void efi_setup_page_tables(void)
 {
+       unsigned long text;
+       unsigned npages;
+       struct page *page;
+
        efi_scratch.efi_pgt = (pgd_t *)(unsigned long)real_mode_header->trampoline_pgd;
 
-       if (!efi_enabled(EFI_OLD_MEMMAP))
-               efi_scratch.use_pgd = true;
+       if (efi_enabled(EFI_OLD_MEMMAP))
+               return;
+
+       efi_scratch.use_pgd = true;
+
+       /*
+        * When making calls to the firmware everything needs to be 1:1
+        * mapped and addressable with 32-bit pointers. Map the kernel
+        * text and allocate a new stack because we can't rely on the
+        * stack pointer being < 4GB.
+        */
+       if (!IS_ENABLED(CONFIG_EFI_MIXED))
+               return;
+
+       page = alloc_page(GFP_KERNEL|__GFP_DMA32);
+       if (!page)
+               panic("Unable to allocate EFI runtime stack < 4GB\n");
+
+       efi_scratch.phys_stack = virt_to_phys(page_address(page));
+       efi_scratch.phys_stack += PAGE_SIZE; /* stack grows down */
+
+       npages = (_end - _text) >> PAGE_SHIFT;
+       text = __pa(_text);
+
+       if (kernel_map_pages_in_pgd(__va(efi_scratch.efi_pgt),
+                                   text >> PAGE_SHIFT, text, npages, 0)) {
+               pr_err("Failed to map kernel text 1:1\n");
+       }
 }
 
 static void __init __map_region(efi_memory_desc_t *md, u64 va)
         */
        __map_region(md, md->phys_addr);
 
+       /*
+        * Enforce the 1:1 mapping as the default virtual address when
+        * booting in EFI mixed mode, because even though we may be
+        * running a 64-bit kernel, the firmware may only be 32-bit.
+        */
+       if (!efi_is_native () && IS_ENABLED(CONFIG_EFI_MIXED)) {
+               md->virt_addr = md->phys_addr;
+               return;
+       }
+
        efi_va -= size;
 
        /* Is PA 2M-aligned? */
        if (__supported_pte_mask & _PAGE_NX)
                runtime_code_page_mkexec();
 }
+
+#ifdef CONFIG_EFI_MIXED
+extern efi_status_t efi64_thunk(u32, ...);
+
+#define runtime_service32(func)                                                 \
+({                                                                      \
+       u32 table = (u32)(unsigned long)efi.systab;                      \
+       u32 *rt, *___f;                                                  \
+                                                                        \
+       rt = (u32 *)(table + offsetof(efi_system_table_32_t, runtime));  \
+       ___f = (u32 *)(*rt + offsetof(efi_runtime_services_32_t, func)); \
+       *___f;                                                           \
+})
+
+/*
+ * Switch to the EFI page tables early so that we can access the 1:1
+ * runtime services mappings which are not mapped in any other page
+ * tables. This function must be called before runtime_service32().
+ *
+ * Also, disable interrupts because the IDT points to 64-bit handlers,
+ * which aren't going to function correctly when we switch to 32-bit.
+ */
+#define efi_thunk(f, ...)                                              \
+({                                                                     \
+       efi_status_t __s;                                               \
+       unsigned long flags;                                            \
+       u32 func;                                                       \
+                                                                       \
+       efi_sync_low_kernel_mappings();                                 \
+       local_irq_save(flags);                                          \
+                                                                       \
+       efi_scratch.prev_cr3 = read_cr3();                              \
+       write_cr3((unsigned long)efi_scratch.efi_pgt);                  \
+       __flush_tlb_all();                                              \
+                                                                       \
+       func = runtime_service32(f);                                    \
+       __s = efi64_thunk(func, __VA_ARGS__);                   \
+                                                                       \
+       write_cr3(efi_scratch.prev_cr3);                                \
+       __flush_tlb_all();                                              \
+       local_irq_restore(flags);                                       \
+                                                                       \
+       __s;                                                            \
+})
+
+efi_status_t efi_thunk_set_virtual_address_map(
+       void *phys_set_virtual_address_map,
+       unsigned long memory_map_size,
+       unsigned long descriptor_size,
+       u32 descriptor_version,
+       efi_memory_desc_t *virtual_map)
+{
+       efi_status_t status;
+       unsigned long flags;
+       u32 func;
+
+       efi_sync_low_kernel_mappings();
+       local_irq_save(flags);
+
+       efi_scratch.prev_cr3 = read_cr3();
+       write_cr3((unsigned long)efi_scratch.efi_pgt);
+       __flush_tlb_all();
+
+       func = (u32)(unsigned long)phys_set_virtual_address_map;
+       status = efi64_thunk(func, memory_map_size, descriptor_size,
+                            descriptor_version, virtual_map);
+
+       write_cr3(efi_scratch.prev_cr3);
+       __flush_tlb_all();
+       local_irq_restore(flags);
+
+       return status;
+}
+
+static efi_status_t efi_thunk_get_time(efi_time_t *tm, efi_time_cap_t *tc)
+{
+       efi_status_t status;
+       u32 phys_tm, phys_tc;
+
+       spin_lock(&rtc_lock);
+
+       phys_tm = virt_to_phys(tm);
+       phys_tc = virt_to_phys(tc);
+
+       status = efi_thunk(get_time, phys_tm, phys_tc);
+
+       spin_unlock(&rtc_lock);
+
+       return status;
+}
+
+static efi_status_t efi_thunk_set_time(efi_time_t *tm)
+{
+       efi_status_t status;
+       u32 phys_tm;
+
+       spin_lock(&rtc_lock);
+
+       phys_tm = virt_to_phys(tm);
+
+       status = efi_thunk(set_time, phys_tm);
+
+       spin_unlock(&rtc_lock);
+
+       return status;
+}
+
+static efi_status_t
+efi_thunk_get_wakeup_time(efi_bool_t *enabled, efi_bool_t *pending,
+                         efi_time_t *tm)
+{
+       efi_status_t status;
+       u32 phys_enabled, phys_pending, phys_tm;
+
+       spin_lock(&rtc_lock);
+
+       phys_enabled = virt_to_phys(enabled);
+       phys_pending = virt_to_phys(pending);
+       phys_tm = virt_to_phys(tm);
+
+       status = efi_thunk(get_wakeup_time, phys_enabled,
+                            phys_pending, phys_tm);
+
+       spin_unlock(&rtc_lock);
+
+       return status;
+}
+
+static efi_status_t
+efi_thunk_set_wakeup_time(efi_bool_t enabled, efi_time_t *tm)
+{
+       efi_status_t status;
+       u32 phys_tm;
+
+       spin_lock(&rtc_lock);
+
+       phys_tm = virt_to_phys(tm);
+
+       status = efi_thunk(set_wakeup_time, enabled, phys_tm);
+
+       spin_unlock(&rtc_lock);
+
+       return status;
+}
+
+
+static efi_status_t
+efi_thunk_get_variable(efi_char16_t *name, efi_guid_t *vendor,
+                      u32 *attr, unsigned long *data_size, void *data)
+{
+       efi_status_t status;
+       u32 phys_name, phys_vendor, phys_attr;
+       u32 phys_data_size, phys_data;
+
+       phys_data_size = virt_to_phys(data_size);
+       phys_vendor = virt_to_phys(vendor);
+       phys_name = virt_to_phys(name);
+       phys_attr = virt_to_phys(attr);
+       phys_data = virt_to_phys(data);
+
+       status = efi_thunk(get_variable, phys_name, phys_vendor,
+                          phys_attr, phys_data_size, phys_data);
+
+       return status;
+}
+
+static efi_status_t
+efi_thunk_set_variable(efi_char16_t *name, efi_guid_t *vendor,
+                      u32 attr, unsigned long data_size, void *data)
+{
+       u32 phys_name, phys_vendor, phys_data;
+       efi_status_t status;
+
+       phys_name = virt_to_phys(name);
+       phys_vendor = virt_to_phys(vendor);
+       phys_data = virt_to_phys(data);
+
+       /* If data_size is > sizeof(u32) we've got problems */
+       status = efi_thunk(set_variable, phys_name, phys_vendor,
+                          attr, data_size, phys_data);
+
+       return status;
+}
+
+static efi_status_t
+efi_thunk_get_next_variable(unsigned long *name_size,
+                           efi_char16_t *name,
+                           efi_guid_t *vendor)
+{
+       efi_status_t status;
+       u32 phys_name_size, phys_name, phys_vendor;
+
+       phys_name_size = virt_to_phys(name_size);
+       phys_vendor = virt_to_phys(vendor);
+       phys_name = virt_to_phys(name);
+
+       status = efi_thunk(get_next_variable, phys_name_size,
+                          phys_name, phys_vendor);
+
+       return status;
+}
+
+static efi_status_t
+efi_thunk_get_next_high_mono_count(u32 *count)
+{
+       efi_status_t status;
+       u32 phys_count;
+
+       phys_count = virt_to_phys(count);
+       status = efi_thunk(get_next_high_mono_count, phys_count);
+
+       return status;
+}
+
+static void
+efi_thunk_reset_system(int reset_type, efi_status_t status,
+                      unsigned long data_size, efi_char16_t *data)
+{
+       u32 phys_data;
+
+       phys_data = virt_to_phys(data);
+
+       efi_thunk(reset_system, reset_type, status, data_size, phys_data);
+}
+
+static efi_status_t
+efi_thunk_update_capsule(efi_capsule_header_t **capsules,
+                        unsigned long count, unsigned long sg_list)
+{
+       /*
+        * To properly support this function we would need to repackage
+        * 'capsules' because the firmware doesn't understand 64-bit
+        * pointers.
+        */
+       return EFI_UNSUPPORTED;
+}
+
+static efi_status_t
+efi_thunk_query_variable_info(u32 attr, u64 *storage_space,
+                             u64 *remaining_space,
+                             u64 *max_variable_size)
+{
+       efi_status_t status;
+       u32 phys_storage, phys_remaining, phys_max;
+
+       if (efi.runtime_version < EFI_2_00_SYSTEM_TABLE_REVISION)
+               return EFI_UNSUPPORTED;
+
+       phys_storage = virt_to_phys(storage_space);
+       phys_remaining = virt_to_phys(remaining_space);
+       phys_max = virt_to_phys(max_variable_size);
+
+       status = efi_thunk(query_variable_info, phys_storage,
+                          phys_remaining, phys_max);
+
+       return status;
+}
+
+static efi_status_t
+efi_thunk_query_capsule_caps(efi_capsule_header_t **capsules,
+                            unsigned long count, u64 *max_size,
+                            int *reset_type)
+{
+       /*
+        * To properly support this function we would need to repackage
+        * 'capsules' because the firmware doesn't understand 64-bit
+        * pointers.
+        */
+       return EFI_UNSUPPORTED;
+}
+
+void efi_thunk_runtime_setup(void)
+{
+       efi.get_time = efi_thunk_get_time;
+       efi.set_time = efi_thunk_set_time;
+       efi.get_wakeup_time = efi_thunk_get_wakeup_time;
+       efi.set_wakeup_time = efi_thunk_set_wakeup_time;
+       efi.get_variable = efi_thunk_get_variable;
+       efi.get_next_variable = efi_thunk_get_next_variable;
+       efi.set_variable = efi_thunk_set_variable;
+       efi.get_next_high_mono_count = efi_thunk_get_next_high_mono_count;
+       efi.reset_system = efi_thunk_reset_system;
+       efi.query_variable_info = efi_thunk_query_variable_info;
+       efi.update_capsule = efi_thunk_update_capsule;
+       efi.query_capsule_caps = efi_thunk_query_capsule_caps;
+}
+#endif /* CONFIG_EFI_MIXED */