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x86_64 EFI runtime service support: EFI basic runtime service support

PATCH In review Huang, Ying 1 participant 1 message Oct 30, 2007

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PATCH 1/4 x86_64 EFI runtime service support: EFI basic runtime service support

This patch adds basic runtime services support for EFI x86_64 system. The main file of the patch is the addition of efi_64.c for x86_64. This file is modeled after the EFI IA32 avatar. EFI runtime services initialization are implemented in efi_64.c. Some x86_64 specifics are worth noting here. On x86_64, parameters passed to EFI firmware services need to follow the EFI calling convention. For this purpose, a set of functions named efi_call<x> (<x> is the number of parameters) are implemented. EFI function calls are wrapped before calling the firmware service. The duplicated code between efi_32.c and efi_64.c is placed in efi.c to remove them from efi_32.c.

---

 arch/x86/kernel/Makefile_64   |    1 
 arch/x86/kernel/efi.c         |  483 ++++++++++++++++++++++++++++++++++++++++++
 arch/x86/kernel/efi_64.c      |  181 +++++++++++++++
 arch/x86/kernel/efi_stub_64.S |   68 +++++
 arch/x86/kernel/setup_64.c    |   17 +
 arch/x86_64/Kconfig           |   11 
 include/asm-x86/bootparam.h   |    5 
 include/asm-x86/efi.h         |   70 ++++++
 include/asm-x86/fixmap_64.h   |    3 
 9 files changed, 836 insertions(+), 3 deletions(-)
arch/x86/kernel/efi_64.c new file +181 -0
Index: linux-2.6.24-rc1/arch/x86/kernel/efi_64.c
===================================================================
@@ -0,0 +1,181 @@
+/*
+ * x86_64 specific EFI support functions
+ * Based on Extensible Firmware Interface Specification version 1.0
+ *
+ * Copyright (C) 2005-2008 Intel Co.
+ *	Fenghua Yu <[email protected]>
+ *	Bibo Mao <[email protected]>
+ *	Chandramouli Narayanan <[email protected]>
+ *	Huang Ying <[email protected]>
+ *
+ * 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 <asm/setup.h>
+#include <asm/page.h>
+#include <asm/e820.h>
+#include <asm/pgtable.h>
+#include <asm/tlbflush.h>
+#include <asm/cacheflush.h>
+#include <asm/proto.h>
+#include <asm/efi.h>
+
+int efi_time __initdata;
+
+static pgd_t save_pgd __initdata;
+static unsigned long efi_flags __initdata;
+/* efi_lock protects efi physical mode call */
+static __initdata DEFINE_SPINLOCK(efi_lock);
+
+static int __init setup_noefi(char *arg)
+{
+	efi_enabled = 0;
+	return 0;
+}
+early_param("noefi", setup_noefi);
+
+static int __init setup_efi_time(char *arg)
+{
+	if (arg && !strcmp("on", arg))
+		efi_time = 1;
+	return 0;
+}
+early_param("efi_time", setup_efi_time);
+
+static void __init early_mapping_set_exec(unsigned long start,
+					  unsigned long end,
+					  int executable)
+{
+	pte_t *kpte;
+
+	while (start < end) {
+		kpte = lookup_address((unsigned long)__va(start));
+		BUG_ON(!kpte);
+		if (executable)
+			set_pte(kpte, pte_mkexec(*kpte));
+		else
+			set_pte(kpte, __pte((pte_val(*kpte) | _PAGE_NX) & \
+					    __supported_pte_mask));
+		if (pte_huge(*kpte))
+			start = (start + PMD_SIZE) & PMD_MASK;
+		else
+			start = (start + PAGE_SIZE) & PAGE_MASK;
+	}
+}
+
+static void __init early_runtime_code_mapping_set_exec(int executable)
+{
+	efi_memory_desc_t *md;
+	void *p;
+
+	/* 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) {
+			unsigned long end;
+			end = md->phys_addr + (md->num_pages << PAGE_SHIFT);
+			early_mapping_set_exec(md->phys_addr, end, executable);
+		}
+	}
+}
+
+void __init efi_call_phys_prelog(void) __acquires(efi_lock)
+{
+	unsigned long vaddress;
+
+	/*
+	 * Lock sequence is different from normal case because
+	 * efi_flags is global
+	 */
+	spin_lock(&efi_lock);
+	local_irq_save(efi_flags);
+	early_runtime_code_mapping_set_exec(1);
+	vaddress = (unsigned long)__va(0x0UL);
+	pgd_val(save_pgd) = pgd_val(*pgd_offset_k(0x0UL));
+	set_pgd(pgd_offset_k(0x0UL), *pgd_offset_k(vaddress));
+	global_flush_tlb();
+}
+
+void __init efi_call_phys_epilog(void) __releases(efi_lock)
+{
+	/*
+	 * After the lock is released, the original page table is restored.
+	 */
+	set_pgd(pgd_offset_k(0x0UL), save_pgd);
+	early_runtime_code_mapping_set_exec(0);
+	global_flush_tlb();
+	local_irq_restore(efi_flags);
+	spin_unlock(&efi_lock);
+}
+
+/*
+ * We need to map the EFI memory map again after init_memory_mapping().
+ */
+void __init efi_map_memmap(void)
+{
+	memmap.map = __va(memmap.phys_map);
+	memmap.map_end = memmap.map + (memmap.nr_map * memmap.desc_size);
+}
+
+void __init efi_reserve_bootmem(void)
+{
+	reserve_bootmem_generic((unsigned long)memmap.phys_map,
+				memmap.nr_map * memmap.desc_size);
+}
+
+void __init runtime_code_page_mkexec(void)
+{
+	efi_memory_desc_t *md;
+	void *p;
+
+	/* 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)
+			change_page_attr_addr(md->virt_addr,
+					      md->num_pages,
+					      PAGE_KERNEL_EXEC);
+	}
+	global_flush_tlb();
+}
+
+void __iomem * __init efi_ioremap(unsigned long offset,
+				  unsigned long size)
+{
+	static unsigned pages_mapped;
+	unsigned long last_addr;
+	unsigned i, pages;
+
+	last_addr = offset + size - 1;
+	offset &= PAGE_MASK;
+	pages = (PAGE_ALIGN(last_addr) - offset) >> PAGE_SHIFT;
+	if (pages_mapped + pages > MAX_EFI_IO_PAGES)
+		return NULL;
+
+	for (i = 0; i < pages; i++) {
+		set_fixmap_nocache(FIX_EFI_IO_MAP_FIRST_PAGE - pages_mapped,
+				   offset);
+		offset += PAGE_SIZE;
+		pages_mapped++;
+	}
+
+	return (void __iomem *)__fix_to_virt(FIX_EFI_IO_MAP_FIRST_PAGE - \
+					     (pages_mapped - pages));
+}
arch/x86/kernel/efi_stub_64.S new file +68 -0

68 lines not on this page · raw message

arch/x86/kernel/setup_64.c +16 -1
Index: linux-2.6.24-rc1/arch/x86/kernel/setup_64.c
===================================================================
@@ -39,6 +39,7 @@
 #include <linux/dmi.h>
 #include <linux/dma-mapping.h>
 #include <linux/ctype.h>
+#include <linux/efi.h>
 
 #include <asm/mtrr.h>
 #include <asm/uaccess.h>
@@ -269,6 +270,11 @@
 	rd_prompt = ((boot_params.hdr.ram_size & RAMDISK_PROMPT_FLAG) != 0);
 	rd_doload = ((boot_params.hdr.ram_size & RAMDISK_LOAD_FLAG) != 0);
 #endif
+#ifdef CONFIG_EFI
+	if (!strncmp((char *)&boot_params.efi_info.efi_loader_signature,
+		     "EL64", 4))
+		efi_enabled = 1;
+#endif
 	setup_memory_region();
 	copy_edd();
 
@@ -308,6 +314,8 @@
 	discover_ebda();
 
 	init_memory_mapping(0, (end_pfn_map << PAGE_SHIFT));
+	if (efi_enabled)
+		efi_init();
 
 	dmi_scan_machine();
 
@@ -379,6 +387,12 @@
         */
        acpi_reserve_bootmem();
 #endif
+
+	if (efi_enabled) {
+		efi_map_memmap();
+		efi_reserve_bootmem();
+	}
+
 	/*
 	 * Find and reserve possible boot-time SMP configuration:
 	 */
@@ -448,7 +462,8 @@
 
 #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
include/asm-x86/fixmap_64.h +3 -0
Index: linux-2.6.24-rc1/include/asm-x86/fixmap_64.h
===================================================================
@@ -15,6 +15,7 @@
 #include <asm/apicdef.h>
 #include <asm/page.h>
 #include <asm/vsyscall.h>
+#include <asm/efi.h>
 
 /*
  * Here we define all the compile-time 'special' virtual
@@ -41,6 +42,8 @@
 	FIX_APIC_BASE,	/* local (CPU) APIC) -- required for SMP or not */
 	FIX_IO_APIC_BASE_0,
 	FIX_IO_APIC_BASE_END = FIX_IO_APIC_BASE_0 + MAX_IO_APICS-1,
+	FIX_EFI_IO_MAP_LAST_PAGE,
+	FIX_EFI_IO_MAP_FIRST_PAGE = FIX_EFI_IO_MAP_LAST_PAGE+MAX_EFI_IO_PAGES-1,
 	__end_of_fixed_addresses
 };
 
arch/x86_64/Kconfig +11 -0
Index: linux-2.6.24-rc1/arch/x86_64/Kconfig
===================================================================
@@ -269,6 +269,17 @@
 	depends on SMP && !MK8
 	default y
 
+config EFI
+	bool "EFI runtime service support (EXPERIMENTAL)"
+	---help---
+	  This 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. However,
+	  even with this option, the resultant kernel should continue to
+	  boot on existing non-EFI platforms. For more information on
+	  how to set up [U]EFI64 system, see Documentation/x86_64/uefi.txt.
+
 config MATH_EMULATION
 	bool
 
arch/x86/kernel/Makefile_64 +1 -0
Index: linux-2.6.24-rc1/arch/x86/kernel/Makefile_64
===================================================================
@@ -33,6 +33,7 @@
 obj-$(CONFIG_X86_VSMP)		+= vsmp_64.o
 obj-$(CONFIG_K8_NB)		+= k8.o
 obj-$(CONFIG_AUDIT)		+= audit_64.o
+obj-$(CONFIG_EFI)		+= efi.o efi_64.o efi_stub_64.o
 
 obj-$(CONFIG_MODULES)		+= module_64.o
 obj-$(CONFIG_PCI)		+= early-quirks.o
include/asm-x86/bootparam.h +3 -2
Index: linux-2.6.24-rc1/include/asm-x86/bootparam.h
===================================================================
@@ -54,13 +54,14 @@
 };
 
 struct efi_info {
-	__u32 _pad1;
+	__u32 efi_loader_signature;
 	__u32 efi_systab;
 	__u32 efi_memdesc_size;
 	__u32 efi_memdesc_version;
 	__u32 efi_memmap;
 	__u32 efi_memmap_size;
-	__u32 _pad2[2];
+	__u32 efi_systab_hi;
+	__u32 efi_memmap_hi;
 };
 
 /* The so-called "zeropage" */
arch/x86/kernel/efi.c new file +483 -0

483 lines not on this page · raw message

include/asm-x86/efi.h new file +70 -0

70 lines not on this page · raw message