Merge branch 'efi-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull EFI updates from Ingo Molnar:
 "The main changes in this cycle were:

   - move BGRT handling to drivers/acpi so it can be shared between x86
     and ARM

   - bring the EFI stub's initrd and FDT allocation logic in line with
     the latest changes to the arm64 boot protocol

   - improvements and fixes to the EFI stub's command line parsing
     routines

   - randomize the virtual mapping of the UEFI runtime services on
     ARM/arm64

   - ... and other misc enhancements, cleanups and fixes"

* 'efi-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  efi/libstub/arm: Don't use TASK_SIZE when randomizing the RT space
  ef/libstub/arm/arm64: Randomize the base of the UEFI rt services region
  efi/libstub/arm/arm64: Disable debug prints on 'quiet' cmdline arg
  efi/libstub: Unify command line param parsing
  efi/libstub: Fix harmless command line parsing bug
  efi/arm32-stub: Allow boot-time allocations in the vmlinux region
  x86/efi: Clean up a minor mistake in comment
  efi/pstore: Return error code (if any) from efi_pstore_write()
  efi/bgrt: Enable ACPI BGRT handling on arm64
  x86/efi/bgrt: Move efi-bgrt handling out of arch/x86
  efi/arm-stub: Round up FDT allocation to mapping size
  efi/arm-stub: Correct FDT and initrd allocation rules for arm64

7 files changed, 40 insertions, 94 deletions

diff --git a/arch/arm/include/asm/efi.h b/arch/arm/include/asm/efi.h
index e4e6a9d6a825..17f1f1a814ff 100644
--- a/arch/arm/include/asm/efi.h
+++ b/arch/arm/include/asm/efi.h
@@ -85,6 +85,18 @@ static inline void efifb_setup_from_dmi(struct screen_info *si, const char *opt)
  */
 #define ZIMAGE_OFFSET_LIMIT	SZ_128M
 #define MIN_ZIMAGE_OFFSET	MAX_UNCOMP_KERNEL_SIZE
-#define MAX_FDT_OFFSET		ZIMAGE_OFFSET_LIMIT
+
+/* on ARM, the FDT should be located in the first 128 MB of RAM */
+static inline unsigned long efi_get_max_fdt_addr(unsigned long dram_base)
+{
+	return dram_base + ZIMAGE_OFFSET_LIMIT;
+}
+
+/* on ARM, the initrd should be loaded in a lowmem region */
+static inline unsigned long efi_get_max_initrd_addr(unsigned long dram_base,
+						    unsigned long image_addr)
+{
+	return dram_base + SZ_512M;
+}
 
 #endif /* _ASM_ARM_EFI_H */
diff --git a/arch/arm64/include/asm/efi.h b/arch/arm64/include/asm/efi.h
index e7445281e534..8f3043aba873 100644
--- a/arch/arm64/include/asm/efi.h
+++ b/arch/arm64/include/asm/efi.h
@@ -1,6 +1,7 @@
 #ifndef _ASM_EFI_H
 #define _ASM_EFI_H
 
+#include <asm/boot.h>
 #include <asm/cpufeature.h>
 #include <asm/io.h>
 #include <asm/mmu_context.h>
@@ -46,7 +47,28 @@ int efi_set_mapping_permissions(struct mm_struct *mm, efi_memory_desc_t *md);
  * 2MiB so we know it won't cross a 2MiB boundary.
  */
 #define EFI_FDT_ALIGN	SZ_2M   /* used by allocate_new_fdt_and_exit_boot() */
-#define MAX_FDT_OFFSET	SZ_512M
+
+/* on arm64, the FDT may be located anywhere in system RAM */
+static inline unsigned long efi_get_max_fdt_addr(unsigned long dram_base)
+{
+	return ULONG_MAX;
+}
+
+/*
+ * On arm64, we have to ensure that the initrd ends up in the linear region,
+ * which is a 1 GB aligned region of size '1UL << (VA_BITS - 1)' that is
+ * guaranteed to cover the kernel Image.
+ *
+ * Since the EFI stub is part of the kernel Image, we can relax the
+ * usual requirements in Documentation/arm64/booting.txt, which still
+ * apply to other bootloaders, and are required for some kernel
+ * configurations.
+ */
+static inline unsigned long efi_get_max_initrd_addr(unsigned long dram_base,
+						    unsigned long image_addr)
+{
+	return (image_addr & ~(SZ_1G - 1UL)) + (1UL << (VA_BITS - 1));
+}
 
 #define efi_call_early(f, ...)		sys_table_arg->boottime->f(__VA_ARGS__)
 #define __efi_call_early(f, ...)	f(__VA_ARGS__)
diff --git a/arch/arm64/kernel/acpi.c b/arch/arm64/kernel/acpi.c
index 64d9cbd61678..e25c11e727fe 100644
--- a/arch/arm64/kernel/acpi.c
+++ b/arch/arm64/kernel/acpi.c
@@ -18,6 +18,7 @@
 #include <linux/acpi.h>
 #include <linux/bootmem.h>
 #include <linux/cpumask.h>
+#include <linux/efi-bgrt.h>
 #include <linux/init.h>
 #include <linux/irq.h>
 #include <linux/irqdomain.h>
@@ -233,6 +234,8 @@ done:
 			early_init_dt_scan_chosen_stdout();
 	} else {
 		parse_spcr(earlycon_init_is_deferred);
+		if (IS_ENABLED(CONFIG_ACPI_BGRT))
+			acpi_table_parse(ACPI_SIG_BGRT, acpi_parse_bgrt);
 	}
 }
 
diff --git a/arch/x86/kernel/acpi/boot.c b/arch/x86/kernel/acpi/boot.c
index b2879cc23db4..70854988a963 100644
--- a/arch/x86/kernel/acpi/boot.c
+++ b/arch/x86/kernel/acpi/boot.c
@@ -1564,12 +1564,6 @@ int __init early_acpi_boot_init(void)
 	return 0;
 }
 
-static int __init acpi_parse_bgrt(struct acpi_table_header *table)
-{
-	efi_bgrt_init(table);
-	return 0;
-}
-
 int __init acpi_boot_init(void)
 {
 	/* those are executed after early-quirks are executed */
diff --git a/arch/x86/platform/efi/Makefile b/arch/x86/platform/efi/Makefile
index 066619b0700c..f1d83b34c329 100644
--- a/arch/x86/platform/efi/Makefile
+++ b/arch/x86/platform/efi/Makefile
@@ -1,6 +1,5 @@
 OBJECT_FILES_NON_STANDARD_efi_thunk_$(BITS).o := y
 
 obj-$(CONFIG_EFI) 		+= quirks.o efi.o efi_$(BITS).o efi_stub_$(BITS).o
-obj-$(CONFIG_ACPI_BGRT) += efi-bgrt.o
 obj-$(CONFIG_EARLY_PRINTK_EFI)	+= early_printk.o
 obj-$(CONFIG_EFI_MIXED)		+= efi_thunk_$(BITS).o
diff --git a/arch/x86/platform/efi/efi-bgrt.c b/arch/x86/platform/efi/efi-bgrt.c
deleted file mode 100644
index 04ca8764f0c0..000000000000
--- a/arch/x86/platform/efi/efi-bgrt.c
+++ /dev/null
@@ -1,84 +0,0 @@
-/*
- * Copyright 2012 Intel Corporation
- * Author: Josh Triplett <josh@joshtriplett.org>
- *
- * Based on the bgrt driver:
- * Copyright 2012 Red Hat, Inc <mjg@redhat.com>
- * Author: Matthew Garrett
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2 as
- * published by the Free Software Foundation.
- */
-
-#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
-
-#include <linux/kernel.h>
-#include <linux/init.h>
-#include <linux/acpi.h>
-#include <linux/efi.h>
-#include <linux/efi-bgrt.h>
-
-struct acpi_table_bgrt bgrt_tab;
-size_t __initdata bgrt_image_size;
-
-struct bmp_header {
-	u16 id;
-	u32 size;
-} __packed;
-
-void __init efi_bgrt_init(struct acpi_table_header *table)
-{
-	void *image;
-	struct bmp_header bmp_header;
-	struct acpi_table_bgrt *bgrt = &bgrt_tab;
-
-	if (acpi_disabled)
-		return;
-
-	if (table->length < sizeof(bgrt_tab)) {
-		pr_notice("Ignoring BGRT: invalid length %u (expected %zu)\n",
-		       table->length, sizeof(bgrt_tab));
-		return;
-	}
-	*bgrt = *(struct acpi_table_bgrt *)table;
-	if (bgrt->version != 1) {
-		pr_notice("Ignoring BGRT: invalid version %u (expected 1)\n",
-		       bgrt->version);
-		goto out;
-	}
-	if (bgrt->status & 0xfe) {
-		pr_notice("Ignoring BGRT: reserved status bits are non-zero %u\n",
-		       bgrt->status);
-		goto out;
-	}
-	if (bgrt->image_type != 0) {
-		pr_notice("Ignoring BGRT: invalid image type %u (expected 0)\n",
-		       bgrt->image_type);
-		goto out;
-	}
-	if (!bgrt->image_address) {
-		pr_notice("Ignoring BGRT: null image address\n");
-		goto out;
-	}
-
-	image = early_memremap(bgrt->image_address, sizeof(bmp_header));
-	if (!image) {
-		pr_notice("Ignoring BGRT: failed to map image header memory\n");
-		goto out;
-	}
-
-	memcpy(&bmp_header, image, sizeof(bmp_header));
-	early_memunmap(image, sizeof(bmp_header));
-	if (bmp_header.id != 0x4d42) {
-		pr_notice("Ignoring BGRT: Incorrect BMP magic number 0x%x (expected 0x4d42)\n",
-			bmp_header.id);
-		goto out;
-	}
-	bgrt_image_size = bmp_header.size;
-	efi_mem_reserve(bgrt->image_address, bgrt_image_size);
-
-	return;
-out:
-	memset(bgrt, 0, sizeof(bgrt_tab));
-}
diff --git a/arch/x86/platform/efi/efi_64.c b/arch/x86/platform/efi/efi_64.c
index a4695da42d77..6cbf9e036aa8 100644
--- a/arch/x86/platform/efi/efi_64.c
+++ b/arch/x86/platform/efi/efi_64.c
@@ -47,7 +47,7 @@
 #include <asm/pgalloc.h>
 
 /*
- * We allocate runtime services regions bottom-up, starting from -4G, i.e.
+ * We allocate runtime services regions top-down, starting from -4G, i.e.
  * 0xffff_ffff_0000_0000 and limit EFI VA mapping space to 64G.
  */
 static u64 efi_va = EFI_VA_START;