6 files changed, 156 insertions, 25 deletions

diff --git a/arch/x86/include/asm/efi.h b/arch/x86/include/asm/efi.h
index 9fbaeb239bde..4d1ba80b6ff1 100644
--- a/arch/x86/include/asm/efi.h
+++ b/arch/x86/include/asm/efi.h
@@ -133,6 +133,18 @@ extern void efi_sync_low_kernel_mappings(void);
 extern void efi_setup_page_tables(void);
 extern void __init old_map_region(efi_memory_desc_t *md);
 
+struct efi_setup_data {
+        u64 fw_vendor;
+        u64 runtime;
+        u64 tables;
+        u64 smbios;
+        u64 reserved[8];
+};
+
+extern u64 efi_setup;
+extern u32 efi_data_len;
+extern void parse_efi_setup(u64 phys_addr, u32 data_len);
+
 #ifdef CONFIG_EFI
 
 static inline bool efi_is_native(void)
diff --git a/arch/x86/include/uapi/asm/bootparam.h b/arch/x86/include/uapi/asm/bootparam.h
index 9c3733c5f8f7..64fe421aab65 100644
--- a/arch/x86/include/uapi/asm/bootparam.h
+++ b/arch/x86/include/uapi/asm/bootparam.h
@@ -6,6 +6,7 @@
 #define SETUP_E820_EXT                  1
 #define SETUP_DTB                       2
 #define SETUP_PCI                       3
+#define SETUP_EFI                       4
 
 /* ram_size flags */
 #define RAMDISK_IMAGE_START_MASK        0x07FF
diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c
index cb233bc9dee3..24536f7a0ae6 100644
--- a/arch/x86/kernel/setup.c
+++ b/arch/x86/kernel/setup.c
@@ -447,6 +447,9 @@ static void __init parse_setup_data(void)
                 case SETUP_DTB:
                         add_dtb(pa_data);
                         break;
+                case SETUP_EFI:
+                        parse_efi_setup(pa_data, data_len);
+                        break;
                 default:
                         break;
                 }
diff --git a/arch/x86/platform/efi/efi.c b/arch/x86/platform/efi/efi.c
index 74fe7a719508..9965ff403c6e 100644
--- a/arch/x86/platform/efi/efi.c
+++ b/arch/x86/platform/efi/efi.c
@@ -78,6 +78,8 @@ static __initdata efi_config_table_type_t arch_tables[] = {
 
 static void *efi_runtime_map;
 static int nr_efi_runtime_map;
+u64 efi_setup;          /* efi setup_data physical address */
+u32 efi_data_len;       /* efi setup_data payload length */
 
 /*
  * Returns 1 if 'facility' is enabled, 0 otherwise.
@@ -115,7 +117,6 @@ static int __init setup_storage_paranoia(char *arg)
 }
 early_param("efi_no_storage_paranoia", setup_storage_paranoia);
 
-
 static efi_status_t virt_efi_get_time(efi_time_t *tm, efi_time_cap_t *tc)
 {
         unsigned long flags;
@@ -494,18 +495,27 @@ static int __init efi_systab_init(void *phys)
 {
         if (efi_enabled(EFI_64BIT)) {
                 efi_system_table_64_t *systab64;
+                struct efi_setup_data *data = NULL;
                 u64 tmp = 0;
 
+                if (efi_setup) {
+                        data = early_memremap(efi_setup, sizeof(*data));
+                        if (!data)
+                                return -ENOMEM;
+                }
                 systab64 = early_ioremap((unsigned long)phys,
                                          sizeof(*systab64));
                 if (systab64 == NULL) {
                         pr_err("Couldn't map the system table!\n");
+                        if (data)
+                                early_iounmap(data, sizeof(*data));
                         return -ENOMEM;
                 }
 
                 efi_systab.hdr = systab64->hdr;
-                efi_systab.fw_vendor = systab64->fw_vendor;
-                tmp |= systab64->fw_vendor;
+                efi_systab.fw_vendor = data ? (unsigned long)data->fw_vendor :
+                                              systab64->fw_vendor;
+                tmp |= data ? data->fw_vendor : systab64->fw_vendor;
                 efi_systab.fw_revision = systab64->fw_revision;
                 efi_systab.con_in_handle = systab64->con_in_handle;
                 tmp |= systab64->con_in_handle;
@@ -519,15 +529,20 @@ static int __init efi_systab_init(void *phys)
                 tmp |= systab64->stderr_handle;
                 efi_systab.stderr = systab64->stderr;
                 tmp |= systab64->stderr;
-                efi_systab.runtime = (void *)(unsigned long)systab64->runtime;
-                tmp |= systab64->runtime;
+                efi_systab.runtime = data ?
+                                     (void *)(unsigned long)data->runtime :
+                                     (void *)(unsigned long)systab64->runtime;
+                tmp |= data ? data->runtime : systab64->runtime;
                 efi_systab.boottime = (void *)(unsigned long)systab64->boottime;
                 tmp |= systab64->boottime;
                 efi_systab.nr_tables = systab64->nr_tables;
-                efi_systab.tables = systab64->tables;
-                tmp |= systab64->tables;
+                efi_systab.tables = data ? (unsigned long)data->tables :
+                                           systab64->tables;
+                tmp |= data ? data->tables : systab64->tables;
 
                 early_iounmap(systab64, sizeof(*systab64));
+                if (data)
+                        early_iounmap(data, sizeof(*data));
 #ifdef CONFIG_X86_32
                 if (tmp >> 32) {
                         pr_err("EFI data located above 4GB, disabling EFI.\n");
@@ -631,6 +646,71 @@ static int __init efi_memmap_init(void)
         return 0;
 }
 
+/*
+ * A number of config table entries get remapped to virtual addresses
+ * after entering EFI virtual mode. However, the kexec kernel requires
+ * their physical addresses therefore we pass them via setup_data and
+ * correct those entries to their respective physical addresses here.
+ *
+ * Currently only handles smbios which is necessary for some firmware
+ * implementation.
+ */
+static int __init efi_reuse_config(u64 tables, int nr_tables)
+{
+        int i, sz, ret = 0;
+        void *p, *tablep;
+        struct efi_setup_data *data;
+
+        if (!efi_setup)
+                return 0;
+
+        if (!efi_enabled(EFI_64BIT))
+                return 0;
+
+        data = early_memremap(efi_setup, sizeof(*data));
+        if (!data) {
+                ret = -ENOMEM;
+                goto out;
+        }
+
+        if (!data->smbios)
+                goto out_memremap;
+
+        sz = sizeof(efi_config_table_64_t);
+
+        p = tablep = early_memremap(tables, nr_tables * sz);
+        if (!p) {
+                pr_err("Could not map Configuration table!\n");
+                ret = -ENOMEM;
+                goto out_memremap;
+        }
+
+        for (i = 0; i < efi.systab->nr_tables; i++) {
+                efi_guid_t guid;
+
+                guid = ((efi_config_table_64_t *)p)->guid;
+
+                if (!efi_guidcmp(guid, SMBIOS_TABLE_GUID))
+                        ((efi_config_table_64_t *)p)->table = data->smbios;
+                p += sz;
+        }
+        early_iounmap(tablep, nr_tables * sz);
+
+out_memremap:
+        early_iounmap(data, sizeof(*data));
+out:
+        return ret;
+}
+
+static void get_nr_runtime_map(void)
+{
+        if (!efi_setup)
+                return;
+
+        nr_efi_runtime_map = (efi_data_len - sizeof(struct efi_setup_data)) /
+                             sizeof(efi_memory_desc_t);
+}
+
 void __init efi_init(void)
 {
         efi_char16_t *c16;
@@ -638,6 +718,7 @@ void __init efi_init(void)
         int i = 0;
         void *tmp;
 
+        get_nr_runtime_map();
 #ifdef CONFIG_X86_32
         if (boot_params.efi_info.efi_systab_hi ||
             boot_params.efi_info.efi_memmap_hi) {
@@ -676,6 +757,9 @@ void __init efi_init(void)
                 efi.systab->hdr.revision >> 16,
                 efi.systab->hdr.revision & 0xffff, vendor);
 
+        if (efi_reuse_config(efi.systab->tables, efi.systab->nr_tables))
+                return;
+
         if (efi_config_init(arch_tables))
                 return;
 
@@ -861,6 +945,23 @@ out:
 }
 
 /*
+ * Map efi regions which were passed via setup_data. The virt_addr is a fixed
+ * addr which was used in first kernel of a kexec boot.
+ */
+static void __init efi_map_regions_fixed(void)
+{
+        void *p;
+        efi_memory_desc_t *md;
+
+        for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
+                md = p;
+                efi_map_region_fixed(md); /* FIXME: add error handling */
+                get_systab_virt_addr(md);
+        }
+
+}
+
+/*
  * Map efi memory ranges for runtime serivce and update new_memmap with virtual
  * addresses.
  */
@@ -914,6 +1015,10 @@ out:
  * so that we're in a different address space when calling a runtime
  * function. For function arguments passing we do copy the PGDs of the
  * kernel page table into ->trampoline_pgd prior to each call.
+ *
+ * Specially for kexec boot, efi runtime maps in previous kernel should
+ * be passed in via setup_data. In that case runtime ranges will be mapped
+ * to the same virtual addresses as the first kernel.
  */
 void __init efi_enter_virtual_mode(void)
 {
@@ -932,12 +1037,15 @@ void __init efi_enter_virtual_mode(void)
                 return;
         }
 
-        efi_merge_regions();
-
-        new_memmap = efi_map_regions(&count);
-        if (!new_memmap) {
-                pr_err("Error reallocating memory, EFI runtime non-functional!\n");
-                return;
+        if (efi_setup) {
+                efi_map_regions_fixed();
+        } else {
+                efi_merge_regions();
+                new_memmap = efi_map_regions(&count);
+                if (!new_memmap) {
+                        pr_err("Error reallocating memory, EFI runtime non-functional!\n");
+                        return;
+                }
         }
 
         err = save_runtime_map();
@@ -949,16 +1057,18 @@ void __init efi_enter_virtual_mode(void)
         efi_setup_page_tables();
         efi_sync_low_kernel_mappings();
 
-        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 (status != EFI_SUCCESS) {
-                pr_alert("Unable to switch EFI into virtual mode "
-                         "(status=%lx)!\n", status);
-                panic("EFI call to SetVirtualAddressMap() failed!");
+        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 (status != EFI_SUCCESS) {
+                        pr_alert("Unable to switch EFI into virtual mode (status=%lx)!\n",
+                                 status);
+                        panic("EFI call to SetVirtualAddressMap() failed!");
+                }
         }
 
         /*
@@ -993,8 +1103,6 @@ void __init efi_enter_virtual_mode(void)
                          EFI_VARIABLE_BOOTSERVICE_ACCESS |
                          EFI_VARIABLE_RUNTIME_ACCESS,
                          0, NULL);
-
-        return;
 }
 
 /*
diff --git a/arch/x86/platform/efi/efi_32.c b/arch/x86/platform/efi/efi_32.c
index 7b3ec6ed99af..249b183cf417 100644
--- a/arch/x86/platform/efi/efi_32.c
+++ b/arch/x86/platform/efi/efi_32.c
@@ -48,6 +48,7 @@ void __init efi_map_region(efi_memory_desc_t *md)
 }
 
 void __init efi_map_region_fixed(efi_memory_desc_t *md) {}
+void __init parse_efi_setup(u64 phys_addr, u32 data_len) {}
 
 void efi_call_phys_prelog(void)
 {
diff --git a/arch/x86/platform/efi/efi_64.c b/arch/x86/platform/efi/efi_64.c
index ff08cb19630b..324b65103851 100644
--- a/arch/x86/platform/efi/efi_64.c
+++ b/arch/x86/platform/efi/efi_64.c
@@ -228,3 +228,9 @@ void __iomem *__init efi_ioremap(unsigned long phys_addr, unsigned long size,
 
         return (void __iomem *)__va(phys_addr);
 }
+
+void __init parse_efi_setup(u64 phys_addr, u32 data_len)
+{
+        efi_setup = phys_addr + sizeof(struct setup_data);
+        efi_data_len = data_len - sizeof(struct setup_data);
+}