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Diffstat (limited to 'arch/x86/platform/efi/efi_64.c')
-rw-r--r--arch/x86/platform/efi/efi_64.c377
1 files changed, 373 insertions, 4 deletions
diff --git a/arch/x86/platform/efi/efi_64.c b/arch/x86/platform/efi/efi_64.c
index 6284f158a47d..290d397e1dd9 100644
--- a/arch/x86/platform/efi/efi_64.c
+++ b/arch/x86/platform/efi/efi_64.c
@@ -39,6 +39,7 @@
#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;
@@ -58,7 +59,8 @@ struct efi_scratch {
u64 prev_cr3;
pgd_t *efi_pgt;
bool use_pgd;
-};
+ u64 phys_stack;
+} __packed;
static void __init early_code_mapping_set_exec(int executable)
{
@@ -137,12 +139,64 @@ void efi_sync_low_kernel_mappings(void)
sizeof(pgd_t) * num_pgds);
}
-void efi_setup_page_tables(void)
+int efi_setup_page_tables(unsigned long pa_memmap, unsigned num_pages)
{
+ unsigned long text;
+ struct page *page;
+ unsigned npages;
+ pgd_t *pgd;
+
+ if (efi_enabled(EFI_OLD_MEMMAP))
+ return 0;
+
efi_scratch.efi_pgt = (pgd_t *)(unsigned long)real_mode_header->trampoline_pgd;
+ pgd = __va(efi_scratch.efi_pgt);
- if (!efi_enabled(EFI_OLD_MEMMAP))
- efi_scratch.use_pgd = true;
+ /*
+ * It can happen that the physical address of new_memmap lands in memory
+ * which is not mapped in the EFI page table. Therefore we need to go
+ * and ident-map those pages containing the map before calling
+ * phys_efi_set_virtual_address_map().
+ */
+ if (kernel_map_pages_in_pgd(pgd, pa_memmap, pa_memmap, num_pages, _PAGE_NX)) {
+ pr_err("Error ident-mapping new memmap (0x%lx)!\n", pa_memmap);
+ return 1;
+ }
+
+ 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 0;
+
+ 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(pgd, text >> PAGE_SHIFT, text, npages, 0)) {
+ pr_err("Failed to map kernel text 1:1\n");
+ return 1;
+ }
+
+ return 0;
+}
+
+void efi_cleanup_page_tables(unsigned long pa_memmap, unsigned num_pages)
+{
+ pgd_t *pgd = (pgd_t *)__va(real_mode_header->trampoline_pgd);
+
+ kernel_unmap_pages_in_pgd(pgd, pa_memmap, num_pages);
}
static void __init __map_region(efi_memory_desc_t *md, u64 va)
@@ -173,6 +227,16 @@ void __init efi_map_region(efi_memory_desc_t *md)
*/
__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? */
@@ -233,3 +297,308 @@ void __init parse_efi_setup(u64 phys_addr, u32 data_len)
{
efi_setup = phys_addr + sizeof(struct setup_data);
}
+
+void __init efi_runtime_mkexec(void)
+{
+ if (!efi_enabled(EFI_OLD_MEMMAP))
+ return;
+
+ if (__supported_pte_mask & _PAGE_NX)
+ runtime_code_page_mkexec();
+}
+
+void __init efi_dump_pagetable(void)
+{
+#ifdef CONFIG_EFI_PGT_DUMP
+ pgd_t *pgd = (pgd_t *)__va(real_mode_header->trampoline_pgd);
+
+ ptdump_walk_pgd_level(NULL, pgd);
+#endif
+}
+
+#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, attr, 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 */