[CPUFREQ] Document units for transition latency

[mirror_ubuntu-bionic-kernel.git] / arch / x86 / kernel / efi.c

/*
 * Common EFI (Extensible Firmware Interface) support functions
 * Based on Extensible Firmware Interface Specification version 1.0
 *
 * Copyright (C) 1999 VA Linux Systems
 * Copyright (C) 1999 Walt Drummond <drummond@valinux.com>
 * Copyright (C) 1999-2002 Hewlett-Packard Co.
 *      David Mosberger-Tang <davidm@hpl.hp.com>
 *      Stephane Eranian <eranian@hpl.hp.com>
 * 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>
 *
 * Copied from efi_32.c to eliminate the duplicated code between EFI
 * 32/64 support code. --ying 2007-10-26
 *
 * All EFI Runtime Services are not implemented yet as EFI only
 * supports physical mode addressing on SoftSDV. This is to be fixed
 * in a future version.  --drummond 1999-07-20
 *
 * Implemented EFI runtime services and virtual mode calls.  --davidm
 *
 * Goutham Rao: <goutham.rao@intel.com>
 *      Skip non-WB memory and ignore empty memory ranges.
 */

#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/efi.h>
#include <linux/bootmem.h>
#include <linux/spinlock.h>
#include <linux/uaccess.h>
#include <linux/time.h>
#include <linux/io.h>
#include <linux/reboot.h>
#include <linux/bcd.h>

#include <asm/setup.h>
#include <asm/efi.h>
#include <asm/time.h>
#include <asm/cacheflush.h>
#include <asm/tlbflush.h>
#include <asm/x86_init.h>

#define EFI_DEBUG       1
#define PFX             "EFI: "

int efi_enabled;
EXPORT_SYMBOL(efi_enabled);

struct efi efi;
EXPORT_SYMBOL(efi);

struct efi_memory_map memmap;

static struct efi efi_phys __initdata;
static efi_system_table_t efi_systab __initdata;

static int __init setup_noefi(char *arg)
{
        efi_enabled = 0;
        return 0;
}
early_param("noefi", setup_noefi);

int add_efi_memmap;
EXPORT_SYMBOL(add_efi_memmap);

static int __init setup_add_efi_memmap(char *arg)
{
        add_efi_memmap = 1;
        return 0;
}
early_param("add_efi_memmap", setup_add_efi_memmap);


static efi_status_t virt_efi_get_time(efi_time_t *tm, efi_time_cap_t *tc)
{
        return efi_call_virt2(get_time, tm, tc);
}

static efi_status_t virt_efi_set_time(efi_time_t *tm)
{
        return efi_call_virt1(set_time, tm);
}

static efi_status_t virt_efi_get_wakeup_time(efi_bool_t *enabled,
                                             efi_bool_t *pending,
                                             efi_time_t *tm)
{
        return efi_call_virt3(get_wakeup_time,
                              enabled, pending, tm);
}

static efi_status_t virt_efi_set_wakeup_time(efi_bool_t enabled, efi_time_t *tm)
{
        return efi_call_virt2(set_wakeup_time,
                              enabled, tm);
}

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_virt5(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_virt3(get_next_variable,
                              name_size, name, vendor);
}

static efi_status_t virt_efi_set_variable(efi_char16_t *name,
                                          efi_guid_t *vendor,
                                          unsigned long attr,
                                          unsigned long data_size,
                                          void *data)
{
        return efi_call_virt5(set_variable,
                              name, vendor, attr,
                              data_size, data);
}

static efi_status_t virt_efi_get_next_high_mono_count(u32 *count)
{
        return efi_call_virt1(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_virt4(reset_system, reset_type, status,
                       data_size, data);
}

static efi_status_t virt_efi_set_virtual_address_map(
        unsigned long memory_map_size,
        unsigned long descriptor_size,
        u32 descriptor_version,
        efi_memory_desc_t *virtual_map)
{
        return efi_call_virt4(set_virtual_address_map,
                              memory_map_size, descriptor_size,
                              descriptor_version, virtual_map);
}

static efi_status_t __init phys_efi_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;

        efi_call_phys_prelog();
        status = efi_call_phys4(efi_phys.set_virtual_address_map,
                                memory_map_size, descriptor_size,
                                descriptor_version, virtual_map);
        efi_call_phys_epilog();
        return status;
}

static efi_status_t __init phys_efi_get_time(efi_time_t *tm,
                                             efi_time_cap_t *tc)
{
        efi_status_t status;

        efi_call_phys_prelog();
        status = efi_call_phys2(efi_phys.get_time, tm, tc);
        efi_call_phys_epilog();
        return status;
}

int efi_set_rtc_mmss(unsigned long nowtime)
{
        int real_seconds, real_minutes;
        efi_status_t    status;
        efi_time_t      eft;
        efi_time_cap_t  cap;

        status = efi.get_time(&eft, &cap);
        if (status != EFI_SUCCESS) {
                printk(KERN_ERR "Oops: efitime: can't read time!\n");
                return -1;
        }

        real_seconds = nowtime % 60;
        real_minutes = nowtime / 60;
        if (((abs(real_minutes - eft.minute) + 15)/30) & 1)
                real_minutes += 30;
        real_minutes %= 60;
        eft.minute = real_minutes;
        eft.second = real_seconds;

        status = efi.set_time(&eft);
        if (status != EFI_SUCCESS) {
                printk(KERN_ERR "Oops: efitime: can't write time!\n");
                return -1;
        }
        return 0;
}

unsigned long efi_get_time(void)
{
        efi_status_t status;
        efi_time_t eft;
        efi_time_cap_t cap;

        status = efi.get_time(&eft, &cap);
        if (status != EFI_SUCCESS)
                printk(KERN_ERR "Oops: efitime: can't read time!\n");

        return mktime(eft.year, eft.month, eft.day, eft.hour,
                      eft.minute, eft.second);
}

/*
 * Tell the kernel about the EFI memory map.  This might include
 * more than the max 128 entries that can fit in the e820 legacy
 * (zeropage) memory map.
 */

static void __init do_add_efi_memmap(void)
{
        void *p;

        for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
                efi_memory_desc_t *md = p;
                unsigned long long start = md->phys_addr;
                unsigned long long size = md->num_pages << EFI_PAGE_SHIFT;
                int e820_type;

                switch (md->type) {
                case EFI_LOADER_CODE:
                case EFI_LOADER_DATA:
                case EFI_BOOT_SERVICES_CODE:
                case EFI_BOOT_SERVICES_DATA:
                case EFI_CONVENTIONAL_MEMORY:
                        if (md->attribute & EFI_MEMORY_WB)
                                e820_type = E820_RAM;
                        else
                                e820_type = E820_RESERVED;
                        break;
                case EFI_ACPI_RECLAIM_MEMORY:
                        e820_type = E820_ACPI;
                        break;
                case EFI_ACPI_MEMORY_NVS:
                        e820_type = E820_NVS;
                        break;
                case EFI_UNUSABLE_MEMORY:
                        e820_type = E820_UNUSABLE;
                        break;
                default:
                        /*
                         * EFI_RESERVED_TYPE EFI_RUNTIME_SERVICES_CODE
                         * EFI_RUNTIME_SERVICES_DATA EFI_MEMORY_MAPPED_IO
                         * EFI_MEMORY_MAPPED_IO_PORT_SPACE EFI_PAL_CODE
                         */
                        e820_type = E820_RESERVED;
                        break;
                }
                e820_add_region(start, size, e820_type);
        }
        sanitize_e820_map(e820.map, ARRAY_SIZE(e820.map), &e820.nr_map);
}

void __init efi_reserve_early(void)
{
        unsigned long pmap;

#ifdef CONFIG_X86_32
        pmap = boot_params.efi_info.efi_memmap;
#else
        pmap = (boot_params.efi_info.efi_memmap |
                ((__u64)boot_params.efi_info.efi_memmap_hi<<32));
#endif
        memmap.phys_map = (void *)pmap;
        memmap.nr_map = boot_params.efi_info.efi_memmap_size /
                boot_params.efi_info.efi_memdesc_size;
        memmap.desc_version = boot_params.efi_info.efi_memdesc_version;
        memmap.desc_size = boot_params.efi_info.efi_memdesc_size;
        reserve_early(pmap, pmap + memmap.nr_map * memmap.desc_size,
                      "EFI memmap");
}

#if EFI_DEBUG
static void __init print_efi_memmap(void)
{
        efi_memory_desc_t *md;
        void *p;
        int i;

        for (p = memmap.map, i = 0;
             p < memmap.map_end;
             p += memmap.desc_size, i++) {
                md = p;
                printk(KERN_INFO PFX "mem%02u: type=%u, attr=0x%llx, "
                        "range=[0x%016llx-0x%016llx) (%lluMB)\n",
                        i, md->type, md->attribute, md->phys_addr,
                        md->phys_addr + (md->num_pages << EFI_PAGE_SHIFT),
                        (md->num_pages >> (20 - EFI_PAGE_SHIFT)));
        }
}
#endif  /*  EFI_DEBUG  */

void __init efi_init(void)
{
        efi_config_table_t *config_tables;
        efi_runtime_services_t *runtime;
        efi_char16_t *c16;
        char vendor[100] = "unknown";
        int i = 0;
        void *tmp;

#ifdef CONFIG_X86_32
        efi_phys.systab = (efi_system_table_t *)boot_params.efi_info.efi_systab;
#else
        efi_phys.systab = (efi_system_table_t *)
                (boot_params.efi_info.efi_systab |
                 ((__u64)boot_params.efi_info.efi_systab_hi<<32));
#endif

        efi.systab = early_ioremap((unsigned long)efi_phys.systab,
                                   sizeof(efi_system_table_t));
        if (efi.systab == NULL)
                printk(KERN_ERR "Couldn't map the EFI system table!\n");
        memcpy(&efi_systab, efi.systab, sizeof(efi_system_table_t));
        early_iounmap(efi.systab, sizeof(efi_system_table_t));
        efi.systab = &efi_systab;

        /*
         * Verify the EFI Table
         */
        if (efi.systab->hdr.signature != EFI_SYSTEM_TABLE_SIGNATURE)
                printk(KERN_ERR "EFI system table signature incorrect!\n");
        if ((efi.systab->hdr.revision >> 16) == 0)
                printk(KERN_ERR "Warning: EFI system table version "
                       "%d.%02d, expected 1.00 or greater!\n",
                       efi.systab->hdr.revision >> 16,
                       efi.systab->hdr.revision & 0xffff);

        /*
         * Show what we know for posterity
         */
        c16 = tmp = early_ioremap(efi.systab->fw_vendor, 2);
        if (c16) {
                for (i = 0; i < sizeof(vendor) - 1 && *c16; ++i)
                        vendor[i] = *c16++;
                vendor[i] = '\0';
        } else
                printk(KERN_ERR PFX "Could not map the firmware vendor!\n");
        early_iounmap(tmp, 2);

        printk(KERN_INFO "EFI v%u.%.02u by %s \n",
               efi.systab->hdr.revision >> 16,
               efi.systab->hdr.revision & 0xffff, vendor);

        /*
         * Let's see what config tables the firmware passed to us.
         */
        config_tables = early_ioremap(
                efi.systab->tables,
                efi.systab->nr_tables * sizeof(efi_config_table_t));
        if (config_tables == NULL)
                printk(KERN_ERR "Could not map EFI Configuration Table!\n");

        printk(KERN_INFO);
        for (i = 0; i < efi.systab->nr_tables; i++) {
                if (!efi_guidcmp(config_tables[i].guid, MPS_TABLE_GUID)) {
                        efi.mps = config_tables[i].table;
                        printk(" MPS=0x%lx ", config_tables[i].table);
                } else if (!efi_guidcmp(config_tables[i].guid,
                                        ACPI_20_TABLE_GUID)) {
                        efi.acpi20 = config_tables[i].table;
                        printk(" ACPI 2.0=0x%lx ", config_tables[i].table);
                } else if (!efi_guidcmp(config_tables[i].guid,
                                        ACPI_TABLE_GUID)) {
                        efi.acpi = config_tables[i].table;
                        printk(" ACPI=0x%lx ", config_tables[i].table);
                } else if (!efi_guidcmp(config_tables[i].guid,
                                        SMBIOS_TABLE_GUID)) {
                        efi.smbios = config_tables[i].table;
                        printk(" SMBIOS=0x%lx ", config_tables[i].table);
#ifdef CONFIG_X86_UV
                } else if (!efi_guidcmp(config_tables[i].guid,
                                        UV_SYSTEM_TABLE_GUID)) {
                        efi.uv_systab = config_tables[i].table;
                        printk(" UVsystab=0x%lx ", config_tables[i].table);
#endif
                } else if (!efi_guidcmp(config_tables[i].guid,
                                        HCDP_TABLE_GUID)) {
                        efi.hcdp = config_tables[i].table;
                        printk(" HCDP=0x%lx ", config_tables[i].table);
                } else if (!efi_guidcmp(config_tables[i].guid,
                                        UGA_IO_PROTOCOL_GUID)) {
                        efi.uga = config_tables[i].table;
                        printk(" UGA=0x%lx ", config_tables[i].table);
                }
        }
        printk("\n");
        early_iounmap(config_tables,
                          efi.systab->nr_tables * sizeof(efi_config_table_t));

        /*
         * 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.
         */
        runtime = early_ioremap((unsigned long)efi.systab->runtime,
                                sizeof(efi_runtime_services_t));
        if (runtime != NULL) {
                /*
                 * 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.set_virtual_address_map =
                        (efi_set_virtual_address_map_t *)
                        runtime->set_virtual_address_map;
                /*
                 * Make efi_get_time can be called before entering
                 * virtual mode.
                 */
                efi.get_time = phys_efi_get_time;
        } else
                printk(KERN_ERR "Could not map the EFI runtime service "
                       "table!\n");
        early_iounmap(runtime, sizeof(efi_runtime_services_t));

        /* Map the EFI memory map */
        memmap.map = early_ioremap((unsigned long)memmap.phys_map,
                                   memmap.nr_map * memmap.desc_size);
        if (memmap.map == NULL)
                printk(KERN_ERR "Could not map the EFI memory map!\n");
        memmap.map_end = memmap.map + (memmap.nr_map * memmap.desc_size);

        if (memmap.desc_size != sizeof(efi_memory_desc_t))
                printk(KERN_WARNING
                  "Kernel-defined memdesc doesn't match the one from EFI!\n");

        if (add_efi_memmap)
                do_add_efi_memmap();

#ifdef CONFIG_X86_32
        x86_platform.get_wallclock = efi_get_time;
        x86_platform.set_wallclock = efi_set_rtc_mmss;
#endif

        /* Setup for EFI runtime service */
        reboot_type = BOOT_EFI;

#if EFI_DEBUG
        print_efi_memmap();
#endif
}

static void __init runtime_code_page_mkexec(void)
{
        efi_memory_desc_t *md;
        void *p;
        u64 addr, npages;

        /* Make EFI runtime 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)
                        continue;

                addr = md->virt_addr;
                npages = md->num_pages;
                memrange_efi_to_native(&addr, &npages);
                set_memory_x(addr, npages);
        }
}

/*
 * This function will switch the EFI runtime services to virtual mode.
 * Essentially, look through the EFI memmap and map every region that
 * has the runtime attribute bit set in its memory descriptor and update
 * that memory descriptor with the virtual address obtained from ioremap().
 * This enables the runtime services to be called without having to
 * thunk back into physical mode for every invocation.
 */
void __init efi_enter_virtual_mode(void)
{
        efi_memory_desc_t *md;
        efi_status_t status;
        unsigned long size;
        u64 end, systab, addr, npages, end_pfn;
        void *p, *va;

        efi.systab = NULL;
        for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
                md = p;
                if (!(md->attribute & EFI_MEMORY_RUNTIME))
                        continue;

                size = md->num_pages << EFI_PAGE_SHIFT;
                end = md->phys_addr + size;

                end_pfn = PFN_UP(end);
                if (end_pfn <= max_low_pfn_mapped
                    || (end_pfn > (1UL << (32 - PAGE_SHIFT))
                        && end_pfn <= max_pfn_mapped))
                        va = __va(md->phys_addr);
                else
                        va = efi_ioremap(md->phys_addr, size, md->type);

                md->virt_addr = (u64) (unsigned long) va;

                if (!va) {
                        printk(KERN_ERR PFX "ioremap of 0x%llX failed!\n",
                               (unsigned long long)md->phys_addr);
                        continue;
                }

                if (!(md->attribute & EFI_MEMORY_WB)) {
                        addr = md->virt_addr;
                        npages = md->num_pages;
                        memrange_efi_to_native(&addr, &npages);
                        set_memory_uc(addr, npages);
                }

                systab = (u64) (unsigned long) efi_phys.systab;
                if (md->phys_addr <= systab && systab < end) {
                        systab += md->virt_addr - md->phys_addr;
                        efi.systab = (efi_system_table_t *) (unsigned long) systab;
                }
        }

        BUG_ON(!efi.systab);

        status = phys_efi_set_virtual_address_map(
                memmap.desc_size * memmap.nr_map,
                memmap.desc_size,
                memmap.desc_version,
                memmap.phys_map);

        if (status != EFI_SUCCESS) {
                printk(KERN_ALERT "Unable to switch EFI into virtual mode "
                       "(status=%lx)!\n", status);
                panic("EFI call to SetVirtualAddressMap() failed!");
        }

        /*
         * Now that EFI is in virtual mode, update the function
         * pointers in the runtime service table to the new virtual addresses.
         *
         * Call EFI services through wrapper functions.
         */
        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.set_virtual_address_map = virt_efi_set_virtual_address_map;
        if (__supported_pte_mask & _PAGE_NX)
                runtime_code_page_mkexec();
        early_iounmap(memmap.map, memmap.nr_map * memmap.desc_size);
        memmap.map = NULL;
}

/*
 * Convenience functions to obtain memory types and attributes
 */
u32 efi_mem_type(unsigned long phys_addr)
{
        efi_memory_desc_t *md;
        void *p;

        for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
                md = p;
                if ((md->phys_addr <= phys_addr) &&
                    (phys_addr < (md->phys_addr +
                                  (md->num_pages << EFI_PAGE_SHIFT))))
                        return md->type;
        }
        return 0;
}

u64 efi_mem_attributes(unsigned long phys_addr)
{
        efi_memory_desc_t *md;
        void *p;

        for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
                md = p;
                if ((md->phys_addr <= phys_addr) &&
                    (phys_addr < (md->phys_addr +
                                  (md->num_pages << EFI_PAGE_SHIFT))))
                        return md->attribute;
        }
        return 0;
}