efi: Add a function to look up existing IO memory mappings

[platform/adaptation/renesas_rcar/renesas_kernel.git] / arch / x86 / platform / efi / efi.c

diff --git a/arch/x86/platform/efi/efi.c b/arch/x86/platform/efi/efi.c
index 2dc29f5..f7f928c 100644 (file)
--- a/arch/x86/platform/efi/efi.c
+++ b/arch/x86/platform/efi/efi.c
@@ -234,7 +234,22 @@ static efi_status_t __init phys_efi_set_virtual_address_map(
        return status;
 }
 
-static int efi_set_rtc_mmss(unsigned long nowtime)
+static efi_status_t __init phys_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);
+       efi_call_phys_prelog();
+       status = efi_call_phys2(efi_phys.get_time, virt_to_phys(tm),
+                               virt_to_phys(tc));
+       efi_call_phys_epilog();
+       spin_unlock_irqrestore(&rtc_lock, flags);
+       return status;
+}
+
+int efi_set_rtc_mmss(unsigned long nowtime)
 {
        int real_seconds, real_minutes;
        efi_status_t    status;
@@ -263,7 +278,7 @@ static int efi_set_rtc_mmss(unsigned long nowtime)
        return 0;
 }
 
-static unsigned long efi_get_time(void)
+unsigned long efi_get_time(void)
 {
        efi_status_t status;
        efi_time_t eft;
@@ -404,10 +419,21 @@ void __init efi_reserve_boot_services(void)
        }
 }
 
-static void __init efi_free_boot_services(void)
+static void __init efi_unmap_memmap(void)
+{
+       if (memmap.map) {
+               early_iounmap(memmap.map, memmap.nr_map * memmap.desc_size);
+               memmap.map = NULL;
+       }
+}
+
+void __init efi_free_boot_services(void)
 {
        void *p;
 
+       if (!efi_native)
+               return;
+
        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;
@@ -423,6 +449,8 @@ static void __init efi_free_boot_services(void)
 
                free_bootmem_late(start, size);
        }
+
+       efi_unmap_memmap();
 }
 
 static int __init efi_systab_init(void *phys)
@@ -606,13 +634,18 @@ static int __init efi_runtime_init(void)
        }
        /*
         * We will only need *early* access to the following
-        * EFI runtime service before set_virtual_address_map
+        * 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;
        early_iounmap(runtime, sizeof(efi_runtime_services_t));
 
        return 0;
@@ -700,10 +733,12 @@ void __init efi_init(void)
                efi_enabled = 0;
                return;
        }
+#ifdef CONFIG_X86_32
        if (efi_native) {
                x86_platform.get_wallclock = efi_get_time;
                x86_platform.set_wallclock = efi_set_rtc_mmss;
        }
+#endif
 
 #if EFI_DEBUG
        print_efi_memmap();
@@ -742,6 +777,34 @@ static void __init runtime_code_page_mkexec(void)
 }
 
 /*
+ * We can't ioremap data in EFI boot services RAM, because we've already mapped
+ * it as RAM.  So, look it up in the existing EFI memory map instead.  Only
+ * callable after efi_enter_virtual_mode and before efi_free_boot_services.
+ */
+void __iomem *efi_lookup_mapped_addr(u64 phys_addr)
+{
+       void *p;
+       if (WARN_ON(!memmap.map))
+               return NULL;
+       for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
+               efi_memory_desc_t *md = p;
+               u64 size = md->num_pages << EFI_PAGE_SHIFT;
+               u64 end = md->phys_addr + size;
+               if (!(md->attribute & EFI_MEMORY_RUNTIME) &&
+                   md->type != EFI_BOOT_SERVICES_CODE &&
+                   md->type != EFI_BOOT_SERVICES_DATA)
+                       continue;
+               if (!md->virt_addr)
+                       continue;
+               if (phys_addr >= md->phys_addr && phys_addr < end) {
+                       phys_addr += md->virt_addr - md->phys_addr;
+                       return (__force void __iomem *)(unsigned long)phys_addr;
+               }
+       }
+       return NULL;
+}
+
+/*
  * 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
@@ -765,8 +828,10 @@ void __init efi_enter_virtual_mode(void)
         * non-native EFI
         */
 
-       if (!efi_native)
-               goto out;
+       if (!efi_native) {
+               efi_unmap_memmap();
+               return;
+       }
 
        /* Merge contiguous regions of the same type and attribute */
        for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
@@ -856,18 +921,12 @@ void __init efi_enter_virtual_mode(void)
        }
 
        /*
-        * Thankfully, it does seem that no runtime services other than
-        * SetVirtualAddressMap() will touch boot services code, so we can
-        * get rid of it all at this point
-        */
-       efi_free_boot_services();
-
-       /*
         * 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.runtime_version = efi_systab.fw_revision;
        efi.get_time = virt_efi_get_time;
        efi.set_time = virt_efi_set_time;
        efi.get_wakeup_time = virt_efi_get_wakeup_time;
@@ -884,9 +943,6 @@ void __init efi_enter_virtual_mode(void)
        if (__supported_pte_mask & _PAGE_NX)
                runtime_code_page_mkexec();
 
-out:
-       early_iounmap(memmap.map, memmap.nr_map * memmap.desc_size);
-       memmap.map = NULL;
        kfree(new_memmap);
 }