efi/x86: Move UEFI Runtime Services wrappers to generic code

In order for other archs (such as arm64) to be able to reuse the virtual
mode function call wrappers, move them to drivers/firmware/efi/runtime-wrappers.c.

Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>

3 files changed, 165 insertions, 0 deletions

diff --git a/drivers/firmware/efi/Kconfig b/drivers/firmware/efi/Kconfig
index d420ae2d3413..588dc47e7075 100644
--- a/drivers/firmware/efi/Kconfig
+++ b/drivers/firmware/efi/Kconfig
@@ -54,6 +54,9 @@ config EFI_PARAMS_FROM_FDT
           the EFI runtime support gets system table address, memory
           map address, and other parameters from the device tree.
 
+config EFI_RUNTIME_WRAPPERS
+        bool
+
 endmenu
 
 config UEFI_CPER
diff --git a/drivers/firmware/efi/Makefile b/drivers/firmware/efi/Makefile
index 9553496b0f43..e1096539eedb 100644
--- a/drivers/firmware/efi/Makefile
+++ b/drivers/firmware/efi/Makefile
@@ -6,3 +6,4 @@ obj-$(CONFIG_EFI_VARS)			+= efivars.o
 obj-$(CONFIG_EFI_VARS_PSTORE)           += efi-pstore.o
 obj-$(CONFIG_UEFI_CPER)                 += cper.o
 obj-$(CONFIG_EFI_RUNTIME_MAP)           += runtime-map.o
+obj-$(CONFIG_EFI_RUNTIME_WRAPPERS)      += runtime-wrappers.o
diff --git a/drivers/firmware/efi/runtime-wrappers.c b/drivers/firmware/efi/runtime-wrappers.c
new file mode 100644
index 000000000000..10daa4bbb258
--- /dev/null
+++ b/drivers/firmware/efi/runtime-wrappers.c
@@ -0,0 +1,161 @@
+/*
+ * runtime-wrappers.c - Runtime Services function call wrappers
+ *
+ * Copyright (C) 2014 Linaro Ltd. <ard.biesheuvel@linaro.org>
+ *
+ * Split off from arch/x86/platform/efi/efi.c
+ *
+ * Copyright (C) 1999 VA Linux Systems
+ * Copyright (C) 1999 Walt Drummond <drummond@valinux.com>
+ * Copyright (C) 1999-2002 Hewlett-Packard Co.
+ * Copyright (C) 2005-2008 Intel Co.
+ * Copyright (C) 2013 SuSE Labs
+ *
+ * This file is released under the GPLv2.
+ */
+
+#include <linux/efi.h>
+#include <linux/spinlock.h>             /* spinlock_t */
+#include <asm/efi.h>
+
+/*
+ * As per commit ef68c8f87ed1 ("x86: Serialize EFI time accesses on rtc_lock"),
+ * the EFI specification requires that callers of the time related runtime
+ * functions serialize with other CMOS accesses in the kernel, as the EFI time
+ * functions may choose to also use the legacy CMOS RTC.
+ */
+__weak DEFINE_SPINLOCK(rtc_lock);
+
+static efi_status_t virt_efi_get_time(efi_time_t *tm, efi_time_cap_t *tc)
+{
+        unsigned long flags;
+        efi_status_t status;
+
+        spin_lock_irqsave(&rtc_lock, flags);
+        status = efi_call_virt(get_time, tm, tc);
+        spin_unlock_irqrestore(&rtc_lock, flags);
+        return status;
+}
+
+static efi_status_t virt_efi_set_time(efi_time_t *tm)
+{
+        unsigned long flags;
+        efi_status_t status;
+
+        spin_lock_irqsave(&rtc_lock, flags);
+        status = efi_call_virt(set_time, tm);
+        spin_unlock_irqrestore(&rtc_lock, flags);
+        return status;
+}
+
+static efi_status_t virt_efi_get_wakeup_time(efi_bool_t *enabled,
+                                             efi_bool_t *pending,
+                                             efi_time_t *tm)
+{
+        unsigned long flags;
+        efi_status_t status;
+
+        spin_lock_irqsave(&rtc_lock, flags);
+        status = efi_call_virt(get_wakeup_time, enabled, pending, tm);
+        spin_unlock_irqrestore(&rtc_lock, flags);
+        return status;
+}
+
+static efi_status_t virt_efi_set_wakeup_time(efi_bool_t enabled, efi_time_t *tm)
+{
+        unsigned long flags;
+        efi_status_t status;
+
+        spin_lock_irqsave(&rtc_lock, flags);
+        status = efi_call_virt(set_wakeup_time, enabled, tm);
+        spin_unlock_irqrestore(&rtc_lock, flags);
+        return status;
+}
+
+static efi_status_t virt_efi_get_variable(efi_char16_t *name,
+                                          efi_guid_t *vendor,
+                                          u32 *attr,
+                                          unsigned long *data_size,
+                                          void *data)
+{
+        return efi_call_virt(get_variable, name, vendor, attr, data_size, data);
+}
+
+static efi_status_t virt_efi_get_next_variable(unsigned long *name_size,
+                                               efi_char16_t *name,
+                                               efi_guid_t *vendor)
+{
+        return efi_call_virt(get_next_variable, name_size, name, vendor);
+}
+
+static efi_status_t virt_efi_set_variable(efi_char16_t *name,
+                                          efi_guid_t *vendor,
+                                          u32 attr,
+                                          unsigned long data_size,
+                                          void *data)
+{
+        return efi_call_virt(set_variable, name, vendor, attr, data_size, data);
+}
+
+static efi_status_t virt_efi_query_variable_info(u32 attr,
+                                                 u64 *storage_space,
+                                                 u64 *remaining_space,
+                                                 u64 *max_variable_size)
+{
+        if (efi.runtime_version < EFI_2_00_SYSTEM_TABLE_REVISION)
+                return EFI_UNSUPPORTED;
+
+        return efi_call_virt(query_variable_info, attr, storage_space,
+                             remaining_space, max_variable_size);
+}
+
+static efi_status_t virt_efi_get_next_high_mono_count(u32 *count)
+{
+        return efi_call_virt(get_next_high_mono_count, count);
+}
+
+static void virt_efi_reset_system(int reset_type,
+                                  efi_status_t status,
+                                  unsigned long data_size,
+                                  efi_char16_t *data)
+{
+        __efi_call_virt(reset_system, reset_type, status, data_size, data);
+}
+
+static efi_status_t virt_efi_update_capsule(efi_capsule_header_t **capsules,
+                                            unsigned long count,
+                                            unsigned long sg_list)
+{
+        if (efi.runtime_version < EFI_2_00_SYSTEM_TABLE_REVISION)
+                return EFI_UNSUPPORTED;
+
+        return efi_call_virt(update_capsule, capsules, count, sg_list);
+}
+
+static efi_status_t virt_efi_query_capsule_caps(efi_capsule_header_t **capsules,
+                                                unsigned long count,
+                                                u64 *max_size,
+                                                int *reset_type)
+{
+        if (efi.runtime_version < EFI_2_00_SYSTEM_TABLE_REVISION)
+                return EFI_UNSUPPORTED;
+
+        return efi_call_virt(query_capsule_caps, capsules, count, max_size,
+                             reset_type);
+}
+
+void efi_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;
+}