[PATCH] EFI support for ia32

From: Matt Tolentino <metolent@snoqualmie.dp.intel.com>

Attached is a patch that enables EFI boot-up support in ia32 kernels.

In order to continue to determine whether the kernel should initialize using
EFI tables, I've temporarily added a check on the LOADER_TYPE boot parameter.
 Although I haven't requested that elilo be assigned an id for this yet, I've
used this to determine whether the kernel should use the EFI initialization
path as well as a check to see if the EFI_SYSTAB boot parameter contains
anything.  If someone has a better suggestion for determining this, I'm
open...

This patch also uses the existing ioremapping functions to map the efi tables
into kernel virtual address space.  I've added an option such that I could
use Dave Hansen's boot_ioremap() before paging_init().  After paging_init, I
then remap the efi memmap using bt_ioremap for use later.  This has
eliminated the need for several functions...thanks for the suggestions and
thanks for your help Dave.  Still this could use a look-see.

arch/i386/Kconfig

@@ -784,6 +784,25 @@ config MTRR
 
 	  See <file:Documentation/mtrr.txt> for more information.
 
+config EFI
+	bool "Boot from EFI support (EXPERIMENTAL)"
+	depends on ACPI
+	default n
+	---help---
+
+	This enables the the kernel to boot on EFI platforms using
+	system configuration information passed to it from the firmware.
+	This also enables the kernel to use any EFI runtime services that are
+	available (such as the EFI variable services).
+
+	This option is only useful on systems that have EFI firmware
+	and will result in a kernel image that is ~8k larger.  In addition,
+	you must use the latest ELILO loader available at
+	ftp.hpl.hp.com/pub/linux-ia64/ in order to take advantage of kernel
+	initialization using EFI information (neither GRUB nor LILO know
+	anything about EFI).  However, even with this option, the resultant
+	kernel should continue to boot on existing non-EFI platforms.
+
 config HAVE_DEC_LOCK
 	bool
 	depends on (SMP || PREEMPT) && X86_CMPXCHG
@@ -793,7 +812,7 @@ config HAVE_DEC_LOCK
 # Summit needs it only when NUMA is on
 config BOOT_IOREMAP
 	bool
-	depends on ((X86_SUMMIT || X86_GENERICARCH) && NUMA)
+	depends on (((X86_SUMMIT || X86_GENERICARCH) && NUMA) || (X86 && EFI))
 	default y
 
 endmenu

arch/i386/kernel/Makefile

@@ -30,6 +30,7 @@ obj-$(CONFIG_MODULES)		+= module.o
 obj-y				+= sysenter.o vsyscall.o
 obj-$(CONFIG_ACPI_SRAT) 	+= srat.o
 obj-$(CONFIG_HPET_TIMER) 	+= time_hpet.o
+obj-$(CONFIG_EFI) 		+= efi.o efi_stub.o
 
 EXTRA_AFLAGS   := -traditional
 

arch/i386/kernel/acpi/boot.c

@@ -26,6 +26,7 @@
 #include <linux/init.h>
 #include <linux/config.h>
 #include <linux/acpi.h>
+#include <linux/efi.h>
 #include <asm/pgalloc.h>
 #include <asm/io_apic.h>
 #include <asm/apic.h>
@@ -331,6 +332,12 @@ acpi_find_rsdp (void)
 {
 	unsigned long		rsdp_phys = 0;
 
+	if (efi_enabled) {
+		if (efi.acpi20)
+			return __pa(efi.acpi20);
+		else if (efi.acpi)
+			return __pa(efi.acpi);
+	}
 	/*
 	 * Scan memory looking for the RSDP signature. First search EBDA (low
 	 * memory) paragraphs and then search upper memory (E0000-FFFFF).

arch/i386/kernel/efi_stub.S

+/*
+ * EFI call stub for IA32.
+ *
+ * This stub allows us to make EFI calls in physical mode with interrupts
+ * turned off.
+ */
+
+#include <linux/config.h>
+#include <linux/linkage.h>
+#include <asm/page.h>
+#include <asm/pgtable.h>
+
+/*
+ * efi_call_phys(void *, ...) is a function with variable parameters.
+ * All the callers of this function assure that all the parameters are 4-bytes.
+ */
+
+/*
+ * In gcc calling convention, EBX, ESP, EBP, ESI and EDI are all callee save.
+ * So we'd better save all of them at the beginning of this function and restore
+ * at the end no matter how many we use, because we can not assure EFI runtime
+ * service functions will comply with gcc calling convention, too.
+ */
+
+.text
+ENTRY(efi_call_phys)
+	/*
+	 * 0. The function can only be called in Linux kernel. So CS has been
+	 * set to 0x0010, DS and SS have been set to 0x0018. In EFI, I found
+	 * the values of these registers are the same. And, the corresponding
+	 * GDT entries are identical. So I will do nothing about segment reg
+	 * and GDT, but change GDT base register in prelog and epilog.
+	 */
+
+	/*
+	 * 1. Now I am running with EIP = <physical address> + PAGE_OFFSET.
+	 * But to make it smoothly switch from virtual mode to flat mode.
+	 * The mapping of lower virtual memory has been created in prelog and
+	 * epilog.
+	 */
+	movl	$1f, %edx
+	subl	$__PAGE_OFFSET, %edx
+	jmp	*%edx
+1:
+
+	/*
+	 * 2. Now on the top of stack is the return
+	 * address in the caller of efi_call_phys(), then parameter 1,
+	 * parameter 2, ..., param n. To make things easy, we save the return
+	 * address of efi_call_phys in a global variable.
+	 */
+	popl	%edx
+	movl	%edx, saved_return_addr
+	/* get the function pointer into ECX*/
+	popl	%ecx
+	movl	%ecx, efi_rt_function_ptr
+	movl	$2f, %edx
+	subl	$__PAGE_OFFSET, %edx
+	pushl	%edx
+
+	/*
+	 * 3. Clear PG bit in %CR0.
+	 */
+	movl	%cr0, %edx
+	andl	$0x7fffffff, %edx
+	movl	%edx, %cr0
+	jmp	1f
+1:
+
+	/*
+	 * 4. Adjust stack pointer.
+	 */
+	subl	$__PAGE_OFFSET, %esp
+
+	/*
+	 * 5. Call the physical function.
+	 */
+	jmp	*%ecx
+
+2:
+	/*
+	 * 6. After EFI runtime service returns, control will return to
+	 * following instruction. We'd better readjust stack pointer first.
+	 */
+	addl	$__PAGE_OFFSET, %esp
+
+	/*
+	 * 7. Restore PG bit
+	 */
+	movl	%cr0, %edx
+	orl	$0x80000000, %edx
+	movl	%edx, %cr0
+	jmp	1f
+1:
+	/*
+	 * 8. Now restore the virtual mode from flat mode by
+	 * adding EIP with PAGE_OFFSET.
+	 */
+	movl	$1f, %edx
+	jmp	*%edx
+1:
+
+	/*
+	 * 9. Balance the stack. And because EAX contain the return value,
+	 * we'd better not clobber it.
+	 */
+	leal	efi_rt_function_ptr, %edx
+	movl	(%edx), %ecx
+	pushl	%ecx
+
+	/*
+	 * 10. Push the saved return address onto the stack and return.
+	 */
+	leal	saved_return_addr, %edx
+	movl	(%edx), %ecx
+	pushl	%ecx
+	ret
+.previous
+
+.data
+saved_return_addr:
+	.long 0
+efi_rt_function_ptr:
+	.long 0

arch/i386/kernel/reboot.c

@@ -8,6 +8,7 @@
 #include <linux/init.h>
 #include <linux/interrupt.h>
 #include <linux/mc146818rtc.h>
+#include <linux/efi.h>
 #include <asm/uaccess.h>
 #include <asm/apic.h>
 #include "mach_reboot.h"
@@ -263,7 +264,12 @@ void machine_restart(char * __unused)
 	disable_IO_APIC();
 #endif
 
-	if(!reboot_thru_bios) {
+	if (!reboot_thru_bios) {
+		if (efi_enabled) {
+			efi.reset_system(EFI_RESET_COLD, EFI_SUCCESS, 0, 0);
+			__asm__ __volatile__("lidt %0": :"m" (no_idt));
+			__asm__ __volatile__("int3");
+		}
 		/* rebooting needs to touch the page at absolute addr 0 */
 		*((unsigned short *)__va(0x472)) = reboot_mode;
 		for (;;) {
@@ -273,6 +279,8 @@ void machine_restart(char * __unused)
 			__asm__ __volatile__("int3");
 		}
 	}
+	if (efi_enabled)
+		efi.reset_system(EFI_RESET_WARM, EFI_SUCCESS, 0, 0);
 
 	machine_real_restart(jump_to_bios, sizeof(jump_to_bios));
 }
@@ -287,6 +295,8 @@ EXPORT_SYMBOL(machine_halt);
 
 void machine_power_off(void)
 {
+	if (efi_enabled)
+		efi.reset_system(EFI_RESET_SHUTDOWN, EFI_SUCCESS, 0, 0);
 	if (pm_power_off)
 		pm_power_off();
 }

arch/i386/kernel/setup.c

@@ -36,6 +36,8 @@
 #include <linux/root_dev.h>
 #include <linux/highmem.h>
 #include <linux/module.h>
+#include <linux/efi.h>
+#include <linux/init.h>
 #include <video/edid.h>
 #include <asm/e820.h>
 #include <asm/mpspec.h>
@@ -56,6 +58,10 @@ static inline char * __init machine_specific_memory_setup(void);
  * Machine setup..
  */
 
+#ifdef CONFIG_EFI
+int efi_enabled = 0;
+#endif
+
 /* cpu data as detected by the assembly code in head.S */
 struct cpuinfo_x86 new_cpu_data __initdata = { 0, 0, 0, 0, -1, 1, 0, 0, -1 };
 /* common cpu data for all cpus */
@@ -144,6 +150,20 @@ static void __init limit_regions(unsigned long long size)
 	unsigned long long current_addr = 0;
 	int i;
 
+	if (efi_enabled) {
+		for (i = 0; i < memmap.nr_map; i++) {
+			current_addr = memmap.map[i].phys_addr +
+				       (memmap.map[i].num_pages << 12);
+			if (memmap.map[i].type == EFI_CONVENTIONAL_MEMORY) {
+				if (current_addr >= size) {
+					memmap.map[i].num_pages -=
+						(((current_addr-size) + PAGE_SIZE-1) >> PAGE_SHIFT);
+					memmap.nr_map = i + 1;
+					return;
+				}
+			}
+		}
+	}
 	for (i = 0; i < e820.nr_map; i++) {
 		if (e820.map[i].type == E820_RAM) {
 			current_addr = e820.map[i].addr + e820.map[i].size;
@@ -159,17 +179,21 @@ static void __init limit_regions(unsigned long long size)
 static void __init add_memory_region(unsigned long long start,
                                   unsigned long long size, int type)
 {
-	int x = e820.nr_map;
+	int x;
 
-	if (x == E820MAX) {
-	    printk(KERN_ERR "Ooops! Too many entries in the memory map!\n");
-	    return;
-	}
+	if (!efi_enabled) {
+       		x = e820.nr_map;
 
-	e820.map[x].addr = start;
-	e820.map[x].size = size;
-	e820.map[x].type = type;
-	e820.nr_map++;
+		if (x == E820MAX) {
+		    printk(KERN_ERR "Ooops! Too many entries in the memory map!\n");
+		    return;
+		}
+
+		e820.map[x].addr = start;
+		e820.map[x].size = size;
+		e820.map[x].type = type;
+		e820.nr_map++;
+	}
 } /* add_memory_region */
 
 #define E820_DEBUG	1
@@ -446,7 +470,6 @@ static inline void copy_edd(void)
 static void __init setup_memory_region(void)
 {
 	char *who = machine_specific_memory_setup();
-
 	printk(KERN_INFO "BIOS-provided physical RAM map:\n");
 	print_memory_map(who);
 } /* setup_memory_region */
@@ -583,6 +606,23 @@ static void __init parse_cmdline_early (char ** cmdline_p)
 	}
 }
 
+/*
+ * Callback for efi_memory_walk.
+ */
+static int __init
+efi_find_max_pfn(unsigned long start, unsigned long end, void *arg)
+{
+	unsigned long *max_pfn = arg, pfn;
+
+	if (start < end) {
+		pfn = PFN_UP(end -1);
+		if (pfn > *max_pfn)
+			*max_pfn = pfn;
+	}
+	return 0;
+}
+
+
 /*
  * Find the highest page frame number we have available
  */
@@ -591,6 +631,11 @@ void __init find_max_pfn(void)
 	int i;
 
 	max_pfn = 0;
+	if (efi_enabled) {
+		efi_memmap_walk(efi_find_max_pfn, &max_pfn);
+		return;
+	}
+
 	for (i = 0; i < e820.nr_map; i++) {
 		unsigned long start, end;
 		/* RAM? */
@@ -665,6 +710,25 @@ unsigned long __init find_max_low_pfn(void)
 }
 
 #ifndef CONFIG_DISCONTIGMEM
+
+/*
+ * Free all available memory for boot time allocation.  Used
+ * as a callback function by efi_memory_walk()
+ */
+
+static int __init
+free_available_memory(unsigned long start, unsigned long end, void *arg)
+{
+	/* check max_low_pfn */
+	if (start >= ((max_low_pfn + 1) << PAGE_SHIFT))
+		return 0;
+	if (end >= ((max_low_pfn + 1) << PAGE_SHIFT))
+		end = (max_low_pfn + 1) << PAGE_SHIFT;
+	if (start < end)
+		free_bootmem(start, end - start);
+
+	return 0;
+}
 /*
  * Register fully available low RAM pages with the bootmem allocator.
  */
@@ -672,6 +736,10 @@ static void __init register_bootmem_low_pages(unsigned long max_low_pfn)
 {
 	int i;
 
+	if (efi_enabled) {
+		efi_memmap_walk(free_available_memory, NULL);
+		return;
+	}
 	for (i = 0; i < e820.nr_map; i++) {
 		unsigned long curr_pfn, last_pfn, size;
 		/*
@@ -799,9 +867,9 @@ extern unsigned long setup_memory(void);
  * Request address space for all standard RAM and ROM resources
  * and also for regions reported as reserved by the e820.
  */
-static void __init register_memory(unsigned long max_low_pfn)
+static void __init
+legacy_init_iomem_resources(struct resource *code_resource, struct resource *data_resource)
 {
-	unsigned long low_mem_size;
 	int i;
 
 	probe_roms();
@@ -826,11 +894,26 @@ static void __init register_memory(unsigned long max_low_pfn)
 			 *  so we try it repeatedly and let the resource manager
 			 *  test it.
 			 */
-			request_resource(res, &code_resource);
-			request_resource(res, &data_resource);
+			request_resource(res, code_resource);
+			request_resource(res, data_resource);
 		}
 	}
+}
 
+/*
+ * Request address space for all standard resources
+ */
+static void __init register_memory(unsigned long max_low_pfn)
+{
+	unsigned long low_mem_size;
+	int i;
+
+	if (efi_enabled)
+		efi_initialize_iomem_resources(&code_resource, &data_resource);
+	else
+		legacy_init_iomem_resources(&code_resource, &data_resource);
+
+ 	 /* EFI systems may still have VGA */
 	request_graphics_resource();
 
 	/* request I/O space for devices used on all i[345]86 PCs */
@@ -950,6 +1033,13 @@ static int __init noreplacement_setup(char *s)
 
 __setup("noreplacement", noreplacement_setup); 
 
+/*
+ * Determine if we were loaded by an EFI loader.  If so, then we have also been
+ * passed the efi memmap, systab, etc., so we should use these data structures
+ * for initialization.  Note, the efi init code path is determined by the
+ * global efi_enabled. This allows the same kernel image to be used on existing
+ * systems (with a traditional BIOS) as well as on EFI systems.
+ */
 void __init setup_arch(char **cmdline_p)
 {
 	unsigned long max_low_pfn;
@@ -958,6 +1048,18 @@ void __init setup_arch(char **cmdline_p)
 	pre_setup_arch_hook();
 	early_cpu_init();
 
+	/*
+	 * FIXME: This isn't an official loader_type right
+	 * now but does currently work with elilo.
+	 * If we were configured as an EFI kernel, check to make
+	 * sure that we were loaded correctly from elilo and that
+	 * the system table is valid.  If not, then initialize normally.
+	 */
+#ifdef CONFIG_EFI
+	if ((LOADER_TYPE == 0x50) && EFI_SYSTAB)
+		efi_enabled = 1;
+#endif
+
  	ROOT_DEV = old_decode_dev(ORIG_ROOT_DEV);
  	drive_info = DRIVE_INFO;
  	screen_info = SCREEN_INFO;
@@ -979,7 +1081,11 @@ void __init setup_arch(char **cmdline_p)
 	rd_doload = ((RAMDISK_FLAGS & RAMDISK_LOAD_FLAG) != 0);
 #endif
 	ARCH_SETUP
-	setup_memory_region();
+	if (efi_enabled)
+		efi_init();
+	else
+		setup_memory_region();
+
 	copy_edd();
 
 	if (!MOUNT_ROOT_RDONLY)
@@ -1013,6 +1119,8 @@ void __init setup_arch(char **cmdline_p)
 #ifdef CONFIG_X86_GENERICARCH
 	generic_apic_probe(*cmdline_p);
 #endif	
+	if (efi_enabled)
+		efi_map_memmap();
 
 	/*
 	 * Parse the ACPI tables for possible boot-time SMP configuration.
@@ -1028,7 +1136,8 @@ void __init setup_arch(char **cmdline_p)
 
 #ifdef CONFIG_VT
 #if defined(CONFIG_VGA_CONSOLE)
-	conswitchp = &vga_con;
+	if (!efi_enabled || (efi_mem_type(0xa0000) != EFI_CONVENTIONAL_MEMORY))
+		conswitchp = &vga_con;
 #elif defined(CONFIG_DUMMY_CONSOLE)
 	conswitchp = &dummy_con;
 #endif

arch/i386/kernel/time.c

@@ -44,6 +44,7 @@
 #include <linux/module.h>
 #include <linux/sysdev.h>
 #include <linux/bcd.h>
+#include <linux/efi.h>
 
 #include <asm/io.h>
 #include <asm/smp.h>
@@ -174,7 +175,10 @@ static int set_rtc_mmss(unsigned long nowtime)
 
 	/* gets recalled with irq locally disabled */
 	spin_lock(&rtc_lock);
-	retval = mach_set_rtc_mmss(nowtime);
+	if (efi_enabled)
+		retval = efi_set_rtc_mmss(nowtime);
+	else
+		retval = mach_set_rtc_mmss(nowtime);
 	spin_unlock(&rtc_lock);
 
 	return retval;
@@ -232,7 +236,13 @@ static inline void do_timer_interrupt(int irq, void *dev_id,
 			>= USEC_AFTER - ((unsigned) TICK_SIZE) / 2 &&
 	    (xtime.tv_nsec / 1000)
 			<= USEC_BEFORE + ((unsigned) TICK_SIZE) / 2) {
-		if (set_rtc_mmss(xtime.tv_sec) == 0)
+		/* horrible...FIXME */
+		if (efi_enabled) {
+	 		if (efi_set_rtc_mmss(xtime.tv_sec) == 0)
+				last_rtc_update = xtime.tv_sec;
+			else
+				last_rtc_update = xtime.tv_sec - 600;
+		} else if (set_rtc_mmss(xtime.tv_sec) == 0)
 			last_rtc_update = xtime.tv_sec;
 		else
 			last_rtc_update = xtime.tv_sec - 600; /* do it again in 60 s */
@@ -286,7 +296,10 @@ unsigned long get_cmos_time(void)
 
 	spin_lock(&rtc_lock);
 
-	retval = mach_get_cmos_time();
+	if (efi_enabled)
+		retval = efi_get_time();
+	else
+		retval = mach_get_cmos_time();
 
 	spin_unlock(&rtc_lock);
 
@@ -297,6 +310,7 @@ static struct sysdev_class pit_sysclass = {
 	set_kset_name("pit"),
 };
 
+
 /* XXX this driverfs stuff should probably go elsewhere later -john */
 static struct sys_device device_i8253 = {
 	.id	= 0,
@@ -344,7 +358,6 @@ void __init time_init(void)
 		return;
 	}
 #endif
-
 	xtime.tv_sec = get_cmos_time();
 	wall_to_monotonic.tv_sec = -xtime.tv_sec;
 	xtime.tv_nsec = (INITIAL_JIFFIES % HZ) * (NSEC_PER_SEC / HZ);

arch/i386/mm/init.c

@@ -26,6 +26,7 @@
 #include <linux/bootmem.h>
 #include <linux/slab.h>
 #include <linux/proc_fs.h>
+#include <linux/efi.h>
 
 #include <asm/processor.h>
 #include <asm/system.h>
@@ -165,12 +166,30 @@ static inline int page_kills_ppro(unsigned long pagenr)
 	return 0;
 }
 
+extern int is_available_memory(efi_memory_desc_t *);
+
 static inline int page_is_ram(unsigned long pagenr)
 {
 	int i;
+	unsigned long addr, end;
+
+	if (efi_enabled) {
+		efi_memory_desc_t *md;
+
+		for (i = 0; i < memmap.nr_map; i++) {
+			md = &memmap.map[i];
+			if (!is_available_memory(md))
+				continue;
+			addr = (md->phys_addr+PAGE_SIZE-1) >> PAGE_SHIFT;
+			end = (md->phys_addr + (md->num_pages << EFI_PAGE_SHIFT)) >> PAGE_SHIFT;
+
+			if ((pagenr >= addr) && (pagenr < end))
+				return 1;
+		}
+		return 0;
+	}
 
 	for (i = 0; i < e820.nr_map; i++) {
-		unsigned long addr, end;
 
 		if (e820.map[i].type != E820_RAM)	/* not usable memory */
 			continue;

arch/ia64/Kconfig

@@ -164,11 +164,6 @@ config ACPI
 	  The ACPI Sourceforge project may also be of interest:
 	  <http://sf.net/projects/acpi/>
 
-config ACPI_EFI
-	bool
-	depends on !IA64_HP_SIM
-	default y
-
 config ACPI_INTERPRETER
 	bool
 	depends on !IA64_HP_SIM
@@ -404,6 +399,11 @@ config IA64_SALINFO
 	  To use this option, you have to ensure that the "/proc file system
 	  support" (CONFIG_PROC_FS) is enabled, too.
 
+config EFI
+	bool
+	depends on !IA64_HP_SIM
+	default y
+
 config EFI_VARS
 	tristate "/proc/efi/vars support"
 	help

arch/ia64/defconfig

@@ -48,7 +48,6 @@ CONFIG_IA64_HP_ZX1=y
 CONFIG_IA64_PAGE_SIZE_16KB=y
 # CONFIG_IA64_PAGE_SIZE_64KB is not set
 CONFIG_ACPI=y
-CONFIG_ACPI_EFI=y
 CONFIG_ACPI_INTERPRETER=y
 CONFIG_ACPI_KERNEL_CONFIG=y
 CONFIG_IA64_L1_CACHE_SHIFT=7
@@ -76,6 +75,7 @@ CONFIG_IA32_SUPPORT=y
 CONFIG_COMPAT=y
 CONFIG_PERFMON=y
 CONFIG_IA64_PALINFO=y
+CONFIG_EFI=y
 CONFIG_EFI_VARS=y
 CONFIG_NR_CPUS=16
 CONFIG_BINFMT_ELF=y

arch/ia64/kernel/setup.c

@@ -54,6 +54,10 @@
 # error "struct cpuinfo_ia64 too big!"
 #endif
 
+#ifdef CONFIG_EFI
+int efi_enabled = 1;
+#endif
+
 #ifdef CONFIG_SMP
 unsigned long __per_cpu_offset[NR_CPUS];
 #endif

drivers/acpi/Kconfig

@@ -251,12 +251,6 @@ config ACPI_SYSTEM
 	  This driver will enable your system to shut down using ACPI, and
 	  dump your ACPI DSDT table using /proc/acpi/dsdt.
 
-config ACPI_EFI
-	bool
-	depends on ACPI_INTERPRETER
-	depends on IA64
-	default y
-
 config ACPI_RELAXED_AML
 	bool "Relaxed AML"
 	depends on ACPI_INTERPRETER

drivers/acpi/osl.c

@@ -41,10 +41,7 @@
 #include <acpi/acpi_bus.h>
 #include <asm/uaccess.h>
 
-#ifdef CONFIG_ACPI_EFI
 #include <linux/efi.h>
-u64 efi_mem_attributes (u64 phys_addr);
-#endif
 
 
 #define _COMPONENT		ACPI_OS_SERVICES
@@ -140,22 +137,24 @@ acpi_os_free(void *ptr)
 acpi_status
 acpi_os_get_root_pointer(u32 flags, struct acpi_pointer *addr)
 {
-#ifdef CONFIG_ACPI_EFI
-	addr->pointer_type = ACPI_PHYSICAL_POINTER;
-	if (efi.acpi20)
-		addr->pointer.physical = (acpi_physical_address) virt_to_phys(efi.acpi20);
-	else if (efi.acpi)
-		addr->pointer.physical = (acpi_physical_address) virt_to_phys(efi.acpi);
-	else {
-		printk(KERN_ERR PREFIX "System description tables not found\n");
-		return AE_NOT_FOUND;
-	}
-#else
-	if (ACPI_FAILURE(acpi_find_root_pointer(flags, addr))) {
-		printk(KERN_ERR PREFIX "System description tables not found\n");
-		return AE_NOT_FOUND;
+	if (efi_enabled) {
+		addr->pointer_type = ACPI_PHYSICAL_POINTER;
+		if (efi.acpi20)
+			addr->pointer.physical =
+				(acpi_physical_address) virt_to_phys(efi.acpi20);
+		else if (efi.acpi)
+			addr->pointer.physical =
+				(acpi_physical_address) virt_to_phys(efi.acpi);
+		else {
+			printk(KERN_ERR PREFIX "System description tables not found\n");
+			return AE_NOT_FOUND;
+		}
+	} else {
+		if (ACPI_FAILURE(acpi_find_root_pointer(flags, addr))) {
+			printk(KERN_ERR PREFIX "System description tables not found\n");
+			return AE_NOT_FOUND;
+		}
 	}
-#endif /*CONFIG_ACPI_EFI*/
 
 	return AE_OK;
 }
@@ -163,22 +162,22 @@ acpi_os_get_root_pointer(u32 flags, struct acpi_pointer *addr)
 acpi_status
 acpi_os_map_memory(acpi_physical_address phys, acpi_size size, void **virt)
 {
-#ifdef CONFIG_ACPI_EFI
-	if (EFI_MEMORY_WB & efi_mem_attributes(phys)) {
-		*virt = phys_to_virt(phys);
+	if (efi_enabled) {
+		if (EFI_MEMORY_WB & efi_mem_attributes(phys)) {
+			*virt = phys_to_virt(phys);
+		} else {
+			*virt = ioremap(phys, size);
+		}
 	} else {
-		*virt = ioremap(phys, size);
-	}
-#else
-	if (phys > ULONG_MAX) {
-		printk(KERN_ERR PREFIX "Cannot map memory that high\n");
-		return AE_BAD_PARAMETER;
+		if (phys > ULONG_MAX) {
+			printk(KERN_ERR PREFIX "Cannot map memory that high\n");
+			return AE_BAD_PARAMETER;
+		}
+		/*
+	 	 * ioremap checks to ensure this is in reserved space
+	 	 */
+		*virt = ioremap((unsigned long) phys, size);
 	}
-	/*
-	 * ioremap checks to ensure this is in reserved space
-	 */
-	*virt = ioremap((unsigned long) phys, size);
-#endif
 
 	if (!*virt)
 		return AE_NO_MEMORY;
@@ -369,19 +368,17 @@ acpi_os_read_memory(
 {
 	u32			dummy;
 	void			*virt_addr;
-
-#ifdef CONFIG_ACPI_EFI
 	int			iomem = 0;
 
-	if (EFI_MEMORY_WB & efi_mem_attributes(phys_addr)) {
+	if (efi_enabled) {
+		if (EFI_MEMORY_WB & efi_mem_attributes(phys_addr)) {
+			virt_addr = phys_to_virt(phys_addr);
+		} else {
+			iomem = 1;
+			virt_addr = ioremap(phys_addr, width);
+		}
+	} else
 		virt_addr = phys_to_virt(phys_addr);
-	} else {
-		iomem = 1;
-		virt_addr = ioremap(phys_addr, width);
-	}
-#else
-	virt_addr = phys_to_virt(phys_addr);
-#endif
 	if (!value)
 		value = &dummy;
 
@@ -399,10 +396,10 @@ acpi_os_read_memory(
 		BUG();
 	}
 
-#ifdef CONFIG_ACPI_EFI
-	if (iomem)
-		iounmap(virt_addr);
-#endif
+	if (efi_enabled) {
+		if (iomem)
+			iounmap(virt_addr);
+	}
 
 	return AE_OK;
 }
@@ -414,19 +411,17 @@ acpi_os_write_memory(
 	u32			width)
 {
 	void			*virt_addr;
-
-#ifdef CONFIG_ACPI_EFI
 	int			iomem = 0;
 
-	if (EFI_MEMORY_WB & efi_mem_attributes(phys_addr)) {
+	if (efi_enabled) {
+		if (EFI_MEMORY_WB & efi_mem_attributes(phys_addr)) {
+			virt_addr = phys_to_virt(phys_addr);
+		} else {
+			iomem = 1;
+			virt_addr = ioremap(phys_addr, width);
+		}
+	} else
 		virt_addr = phys_to_virt(phys_addr);
-	} else {
-		iomem = 1;
-		virt_addr = ioremap(phys_addr, width);
-	}
-#else
-	virt_addr = phys_to_virt(phys_addr);
-#endif
 
 	switch (width) {
 	case 8:
@@ -442,10 +437,8 @@ acpi_os_write_memory(
 		BUG();
 	}
 
-#ifdef CONFIG_ACPI_EFI
 	if (iomem)
 		iounmap(virt_addr);
-#endif
 
 	return AE_OK;
 }

include/asm-i386/setup.h

@@ -29,6 +29,11 @@
 #define IST_INFO   (*(struct ist_info *) (PARAM+0x60))
 #define DRIVE_INFO (*(struct drive_info_struct *) (PARAM+0x80))
 #define SYS_DESC_TABLE (*(struct sys_desc_table_struct*)(PARAM+0xa0))
+#define EFI_SYSTAB ((efi_system_table_t *) *((unsigned long *)(PARAM+0x1c4)))
+#define EFI_MEMDESC_SIZE (*((unsigned long *) (PARAM+0x1c8)))
+#define EFI_MEMDESC_VERSION (*((unsigned long *) (PARAM+0x1cc)))
+#define EFI_MEMMAP ((efi_memory_desc_t *) *((unsigned long *)(PARAM+0x1d0)))
+#define EFI_MEMMAP_SIZE (*((unsigned long *) (PARAM+0x1d4)))
 #define MOUNT_ROOT_RDONLY (*(unsigned short *) (PARAM+0x1F2))
 #define RAMDISK_FLAGS (*(unsigned short *) (PARAM+0x1F8))
 #define VIDEO_MODE (*(unsigned short *) (PARAM+0x1FA))

include/linux/efi.h

@@ -16,6 +16,8 @@
 #include <linux/time.h>
 #include <linux/types.h>
 #include <linux/proc_fs.h>
+#include <linux/rtc.h>
+#include <linux/ioport.h>
 
 #include <asm/page.h>
 #include <asm/system.h>
@@ -77,18 +79,23 @@ typedef	struct {
 #define EFI_MAX_MEMORY_TYPE		14
 
 /* Attribute values: */
-#define EFI_MEMORY_UC		0x0000000000000001	/* uncached */
-#define EFI_MEMORY_WC		0x0000000000000002	/* write-coalescing */
-#define EFI_MEMORY_WT		0x0000000000000004	/* write-through */
-#define EFI_MEMORY_WB		0x0000000000000008	/* write-back */
-#define EFI_MEMORY_WP		0x0000000000001000	/* write-protect */
-#define EFI_MEMORY_RP		0x0000000000002000	/* read-protect */
-#define EFI_MEMORY_XP		0x0000000000004000	/* execute-protect */
-#define EFI_MEMORY_RUNTIME	0x8000000000000000	/* range requires runtime mapping */
+#define EFI_MEMORY_UC		((u64)0x0000000000000001ULL)	/* uncached */
+#define EFI_MEMORY_WC		((u64)0x0000000000000002ULL)	/* write-coalescing */
+#define EFI_MEMORY_WT		((u64)0x0000000000000004ULL)	/* write-through */
+#define EFI_MEMORY_WB		((u64)0x0000000000000008ULL)	/* write-back */
+#define EFI_MEMORY_WP		((u64)0x0000000000001000ULL)	/* write-protect */
+#define EFI_MEMORY_RP		((u64)0x0000000000002000ULL)	/* read-protect */
+#define EFI_MEMORY_XP		((u64)0x0000000000004000ULL)	/* execute-protect */
+#define EFI_MEMORY_RUNTIME	((u64)0x8000000000000000ULL)	/* range requires runtime mapping */
 #define EFI_MEMORY_DESCRIPTOR_VERSION	1
 
 #define EFI_PAGE_SHIFT		12
 
+/*
+ * For current x86 implementations of EFI, there is
+ * additional padding in the mem descriptors.  This is not
+ * the case in ia64.  Need to have this fixed in the f/w.
+ */
 typedef struct {
 	u32 type;
 	u32 pad;
@@ -96,6 +103,9 @@ typedef struct {
 	u64 virt_addr;
 	u64 num_pages;
 	u64 attribute;
+#if defined (__i386__)
+	u64 pad1;
+#endif
 } efi_memory_desc_t;
 
 typedef int efi_freemem_callback_t (unsigned long start, unsigned long end, void *arg);
@@ -132,11 +142,12 @@ typedef struct {
  */
 #define EFI_RESET_COLD 0
 #define EFI_RESET_WARM 1
+#define EFI_RESET_SHUTDOWN 2
 
 /*
  * EFI Runtime Services table
  */
-#define EFI_RUNTIME_SERVICES_SIGNATURE 0x5652453544e5552
+#define EFI_RUNTIME_SERVICES_SIGNATURE ((u64)0x5652453544e5552ULL)
 #define EFI_RUNTIME_SERVICES_REVISION  0x00010000
 
 typedef struct {
@@ -169,6 +180,10 @@ typedef efi_status_t efi_set_variable_t (efi_char16_t *name, efi_guid_t *vendor,
 typedef efi_status_t efi_get_next_high_mono_count_t (u32 *count);
 typedef void efi_reset_system_t (int reset_type, efi_status_t status,
 				 unsigned long data_size, efi_char16_t *data);
+typedef efi_status_t efi_set_virtual_address_map_t (unsigned long memory_map_size,
+						unsigned long descriptor_size,
+						u32 descriptor_version,
+						efi_memory_desc_t *virtual_map);
 
 /*
  *  EFI Configuration Table and GUID definitions
@@ -194,12 +209,15 @@ typedef void efi_reset_system_t (int reset_type, efi_status_t status,
 #define HCDP_TABLE_GUID	\
     EFI_GUID(  0xf951938d, 0x620b, 0x42ef, 0x82, 0x79, 0xa8, 0x4b, 0x79, 0x61, 0x78, 0x98 )
 
+#define UGA_IO_PROTOCOL_GUID \
+    EFI_GUID(  0x61a4d49e, 0x6f68, 0x4f1b, 0xb9, 0x22, 0xa8, 0x6e, 0xed, 0xb, 0x7, 0xa2 )
+
 typedef struct {
 	efi_guid_t guid;
 	unsigned long table;
 } efi_config_table_t;
 
-#define EFI_SYSTEM_TABLE_SIGNATURE 0x5453595320494249
+#define EFI_SYSTEM_TABLE_SIGNATURE ((u64)0x5453595320494249ULL)
 #define EFI_SYSTEM_TABLE_REVISION  ((1 << 16) | 00)
 
 typedef struct {
@@ -218,6 +236,13 @@ typedef struct {
 	unsigned long tables;
 } efi_system_table_t;
 
+struct efi_memory_map {
+	efi_memory_desc_t *phys_map;
+	efi_memory_desc_t *map;
+	int nr_map;
+	unsigned long desc_version;
+};
+
 /*
  * All runtime access to EFI goes through this structure:
  */
@@ -230,6 +255,7 @@ extern struct efi {
 	void *sal_systab;		/* SAL system table */
 	void *boot_info;		/* boot info table */
 	void *hcdp;			/* HCDP table */
+	void *uga;			/* UGA table */
 	efi_get_time_t *get_time;
 	efi_set_time_t *set_time;
 	efi_get_wakeup_time_t *get_wakeup_time;
@@ -239,6 +265,7 @@ extern struct efi {
 	efi_set_variable_t *set_variable;
 	efi_get_next_high_mono_count_t *get_next_high_mono_count;
 	efi_reset_system_t *reset_system;
+	efi_set_virtual_address_map_t *set_virtual_address_map;
 } efi;
 
 static inline int
@@ -260,12 +287,25 @@ efi_guid_unparse(efi_guid_t *guid, char *out)
 
 extern void efi_init (void);
 extern void efi_map_pal_code (void);
+extern void efi_map_memmap(void);
 extern void efi_memmap_walk (efi_freemem_callback_t callback, void *arg);
 extern void efi_gettimeofday (struct timespec *ts);
 extern void efi_enter_virtual_mode (void);	/* switch EFI to virtual mode, if possible */
 extern u64 efi_get_iobase (void);
 extern u32 efi_mem_type (unsigned long phys_addr);
 extern u64 efi_mem_attributes (unsigned long phys_addr);
+extern void efi_initialize_iomem_resources(struct resource *code_resource,
+					struct resource *data_resource);
+extern efi_status_t phys_efi_get_time(efi_time_t *tm, efi_time_cap_t *tc);
+extern unsigned long inline __init efi_get_time(void);
+extern int inline __init efi_set_rtc_mmss(unsigned long nowtime);
+extern struct efi_memory_map memmap;
+
+#ifdef CONFIG_EFI
+extern int efi_enabled;
+#else
+#define efi_enabled 0
+#endif
 
 /*
  * Variable Attributes

init/main.c

@@ -38,6 +38,7 @@
 #include <linux/moduleparam.h>
 #include <linux/writeback.h>
 #include <linux/cpu.h>
+#include <linux/efi.h>
 
 #include <asm/io.h>
 #include <asm/bugs.h>
@@ -443,6 +444,10 @@ asmlinkage void __init start_kernel(void)
 	pidmap_init();
 	pgtable_cache_init();
 	pte_chain_init();
+#ifdef CONFIG_X86
+	if (efi_enabled)
+		efi_enter_virtual_mode();
+#endif
 	fork_init(num_physpages);
 	proc_caches_init();
 	buffer_init();