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authorAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
committerAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
commit57f0f512b273f60d52568b8c6b77e17f5636edc0 (patch)
tree5e910f0e82173f4ef4f51111366a3f1299037a7b /arch/x86/platform/efi/efi_64.c
Initial import
Diffstat (limited to 'arch/x86/platform/efi/efi_64.c')
-rw-r--r--arch/x86/platform/efi/efi_64.c606
1 files changed, 606 insertions, 0 deletions
diff --git a/arch/x86/platform/efi/efi_64.c b/arch/x86/platform/efi/efi_64.c
new file mode 100644
index 000000000..a0ac0f9c3
--- /dev/null
+++ b/arch/x86/platform/efi/efi_64.c
@@ -0,0 +1,606 @@
+/*
+ * x86_64 specific EFI support functions
+ * Based on Extensible Firmware Interface Specification version 1.0
+ *
+ * Copyright (C) 2005-2008 Intel Co.
+ * Fenghua Yu <fenghua.yu@intel.com>
+ * Bibo Mao <bibo.mao@intel.com>
+ * Chandramouli Narayanan <mouli@linux.intel.com>
+ * Huang Ying <ying.huang@intel.com>
+ *
+ * Code to convert EFI to E820 map has been implemented in elilo bootloader
+ * based on a EFI patch by Edgar Hucek. Based on the E820 map, the page table
+ * is setup appropriately for EFI runtime code.
+ * - mouli 06/14/2007.
+ *
+ */
+
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/mm.h>
+#include <linux/types.h>
+#include <linux/spinlock.h>
+#include <linux/bootmem.h>
+#include <linux/ioport.h>
+#include <linux/module.h>
+#include <linux/efi.h>
+#include <linux/uaccess.h>
+#include <linux/io.h>
+#include <linux/reboot.h>
+#include <linux/slab.h>
+
+#include <asm/setup.h>
+#include <asm/page.h>
+#include <asm/e820.h>
+#include <asm/pgtable.h>
+#include <asm/tlbflush.h>
+#include <asm/proto.h>
+#include <asm/efi.h>
+#include <asm/cacheflush.h>
+#include <asm/fixmap.h>
+#include <asm/realmode.h>
+#include <asm/time.h>
+
+/*
+ * We allocate runtime services regions bottom-up, starting from -4G, i.e.
+ * 0xffff_ffff_0000_0000 and limit EFI VA mapping space to 64G.
+ */
+static u64 efi_va = EFI_VA_START;
+
+/*
+ * Scratch space used for switching the pagetable in the EFI stub
+ */
+struct efi_scratch {
+ u64 r15;
+ u64 prev_cr3;
+ pgd_t *efi_pgt;
+ bool use_pgd;
+ u64 phys_stack;
+} __packed;
+
+static void __init early_code_mapping_set_exec(int executable)
+{
+ efi_memory_desc_t *md;
+ void *p;
+
+ if (!(__supported_pte_mask & _PAGE_NX))
+ return;
+
+ /* Make EFI service code area executable */
+ for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
+ md = p;
+ if (md->type == EFI_RUNTIME_SERVICES_CODE ||
+ md->type == EFI_BOOT_SERVICES_CODE)
+ efi_set_executable(md, executable);
+ }
+}
+
+pgd_t * __init efi_call_phys_prolog(void)
+{
+ unsigned long vaddress;
+ pgd_t *save_pgd;
+
+ int pgd;
+ int n_pgds;
+
+ if (!efi_enabled(EFI_OLD_MEMMAP))
+ return NULL;
+
+ early_code_mapping_set_exec(1);
+
+ n_pgds = DIV_ROUND_UP((max_pfn << PAGE_SHIFT), PGDIR_SIZE);
+ save_pgd = kmalloc(n_pgds * sizeof(pgd_t), GFP_KERNEL);
+
+ for (pgd = 0; pgd < n_pgds; pgd++) {
+ save_pgd[pgd] = *pgd_offset_k(pgd * PGDIR_SIZE);
+ vaddress = (unsigned long)__va(pgd * PGDIR_SIZE);
+ set_pgd(pgd_offset_k(pgd * PGDIR_SIZE), *pgd_offset_k(vaddress));
+ }
+ __flush_tlb_all();
+
+ return save_pgd;
+}
+
+void __init efi_call_phys_epilog(pgd_t *save_pgd)
+{
+ /*
+ * After the lock is released, the original page table is restored.
+ */
+ int pgd_idx;
+ int nr_pgds;
+
+ if (!save_pgd)
+ return;
+
+ nr_pgds = DIV_ROUND_UP((max_pfn << PAGE_SHIFT) , PGDIR_SIZE);
+
+ for (pgd_idx = 0; pgd_idx < nr_pgds; pgd_idx++)
+ set_pgd(pgd_offset_k(pgd_idx * PGDIR_SIZE), save_pgd[pgd_idx]);
+
+ kfree(save_pgd);
+
+ __flush_tlb_all();
+ early_code_mapping_set_exec(0);
+}
+
+/*
+ * Add low kernel mappings for passing arguments to EFI functions.
+ */
+void efi_sync_low_kernel_mappings(void)
+{
+ unsigned num_pgds;
+ pgd_t *pgd = (pgd_t *)__va(real_mode_header->trampoline_pgd);
+
+ if (efi_enabled(EFI_OLD_MEMMAP))
+ return;
+
+ num_pgds = pgd_index(MODULES_END - 1) - pgd_index(PAGE_OFFSET);
+
+ memcpy(pgd + pgd_index(PAGE_OFFSET),
+ init_mm.pgd + pgd_index(PAGE_OFFSET),
+ sizeof(pgd_t) * num_pgds);
+}
+
+int __init 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);
+
+ /*
+ * 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 __init 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)
+{
+ pgd_t *pgd = (pgd_t *)__va(real_mode_header->trampoline_pgd);
+ unsigned long pf = 0;
+
+ if (!(md->attribute & EFI_MEMORY_WB))
+ pf |= _PAGE_PCD;
+
+ if (kernel_map_pages_in_pgd(pgd, md->phys_addr, va, md->num_pages, pf))
+ pr_warn("Error mapping PA 0x%llx -> VA 0x%llx!\n",
+ md->phys_addr, va);
+}
+
+void __init efi_map_region(efi_memory_desc_t *md)
+{
+ unsigned long size = md->num_pages << PAGE_SHIFT;
+ u64 pa = md->phys_addr;
+
+ if (efi_enabled(EFI_OLD_MEMMAP))
+ return old_map_region(md);
+
+ /*
+ * Make sure the 1:1 mappings are present as a catch-all for b0rked
+ * firmware which doesn't update all internal pointers after switching
+ * to virtual mode and would otherwise crap on us.
+ */
+ __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 (!(pa & (PMD_SIZE - 1))) {
+ efi_va &= PMD_MASK;
+ } else {
+ u64 pa_offset = pa & (PMD_SIZE - 1);
+ u64 prev_va = efi_va;
+
+ /* get us the same offset within this 2M page */
+ efi_va = (efi_va & PMD_MASK) + pa_offset;
+
+ if (efi_va > prev_va)
+ efi_va -= PMD_SIZE;
+ }
+
+ if (efi_va < EFI_VA_END) {
+ pr_warn(FW_WARN "VA address range overflow!\n");
+ return;
+ }
+
+ /* Do the VA map */
+ __map_region(md, efi_va);
+ md->virt_addr = efi_va;
+}
+
+/*
+ * kexec kernel will use efi_map_region_fixed to map efi runtime memory ranges.
+ * md->virt_addr is the original virtual address which had been mapped in kexec
+ * 1st kernel.
+ */
+void __init efi_map_region_fixed(efi_memory_desc_t *md)
+{
+ __map_region(md, md->virt_addr);
+}
+
+void __iomem *__init efi_ioremap(unsigned long phys_addr, unsigned long size,
+ u32 type, u64 attribute)
+{
+ unsigned long last_map_pfn;
+
+ if (type == EFI_MEMORY_MAPPED_IO)
+ return ioremap(phys_addr, size);
+
+ last_map_pfn = init_memory_mapping(phys_addr, phys_addr + size);
+ if ((last_map_pfn << PAGE_SHIFT) < phys_addr + size) {
+ unsigned long top = last_map_pfn << PAGE_SHIFT;
+ efi_ioremap(top, size - (top - phys_addr), type, attribute);
+ }
+
+ if (!(attribute & EFI_MEMORY_WB))
+ efi_memory_uc((u64)(unsigned long)__va(phys_addr), 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);
+}
+
+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 */