3 files changed, 43 insertions, 86 deletions
diff --git a/arch/arm/boot/compressed/head.S b/arch/arm/boot/compressed/head.S
index cabdd8f4a248..c79db44ba128 100644
--- a/arch/arm/boot/compressed/head.S
+++ b/arch/arm/boot/compressed/head.S
@@ -287,28 +287,22 @@ not_angel:
 		 */
 		mov	r0, pc
 		cmp	r0, r4
-		ldrcc	r0, LC0+28
+		ldrcc	r0, .Lheadroom
 		addcc	r0, r0, pc
 		cmpcc	r4, r0
 		orrcc	r4, r4, #1		@ remember we skipped cache_on
 		blcs	cache_on
 
-restart:	adr	r0, LC0
-		ldmia	r0, {r1, r2, r3, r6, r11, r12}
-		ldr	sp, [r0, #24]
-
-		/*
-		 * We might be running at a different address.  We need
-		 * to fix up various pointers.
-		 */
-		sub	r0, r0, r1		@ calculate the delta offset
-		add	r6, r6, r0		@ _edata
+restart:	adr	r0, LC1
+		ldr	sp, [r0]
+		ldr	r6, [r0, #4]
+		add	sp, sp, r0
+		add	r6, r6, r0
 
 		get_inflated_image_size	r9, r10, lr
 
 #ifndef CONFIG_ZBOOT_ROM
 		/* malloc space is above the relocated stack (64k max) */
-		add	sp, sp, r0
 		add	r10, sp, #0x10000
 #else
 		/*
@@ -322,9 +316,6 @@ restart:	adr	r0, LC0
 		mov	r5, #0			@ init dtb size to 0
 #ifdef CONFIG_ARM_APPENDED_DTB
 /*
- *   r0  = delta
- *   r2  = BSS start
- *   r3  = BSS end
  *   r4  = final kernel address (possibly with LSB set)
  *   r5  = appended dtb size (still unknown)
  *   r6  = _edata
@@ -332,8 +323,6 @@ restart:	adr	r0, LC0
  *   r8  = atags/device tree pointer
  *   r9  = size of decompressed image
  *   r10 = end of this image, including  bss/stack/malloc space if non XIP
- *   r11 = GOT start
- *   r12 = GOT end
  *   sp  = stack pointer
  *
  * if there are device trees (dtb) appended to zImage, advance r10 so that the
@@ -381,7 +370,6 @@ restart:	adr	r0, LC0
 		/* temporarily relocate the stack past the DTB work space */
 		add	sp, sp, r5
 
-		stmfd	sp!, {r0-r3, ip, lr}
 		mov	r0, r8
 		mov	r1, r6
 		mov	r2, r5
@@ -400,7 +388,6 @@ restart:	adr	r0, LC0
 		mov	r2, r5
 		bleq	atags_to_fdt
 
-		ldmfd	sp!, {r0-r3, ip, lr}
 		sub	sp, sp, r5
 #endif
 
@@ -537,6 +524,10 @@ dtb_check_done:
 		mov	pc, r0
 
 wont_overwrite:
+		adr	r0, LC0
+		ldmia	r0, {r1, r2, r3, r11, r12}
+		sub	r0, r0, r1		@ calculate the delta offset
+
 /*
  * If delta is zero, we are running at the address we were linked at.
  *   r0  = delta
@@ -660,13 +651,18 @@ not_relocated:	mov	r0, #0
 LC0:		.word	LC0			@ r1
 		.word	__bss_start		@ r2
 		.word	_end			@ r3
-		.word	_edata			@ r6
 		.word	_got_start		@ r11
 		.word	_got_end		@ ip
-		.word	.L_user_stack_end	@ sp
-		.word	_end - restart + 16384 + 1024*1024
 		.size	LC0, . - LC0
 
+		.type	LC1, #object
+LC1:		.word	.L_user_stack_end - LC1	@ sp
+		.word	_edata - LC1		@ r6
+		.size	LC1, . - LC1
+
+.Lheadroom:
+		.word	_end - restart + 16384 + 1024*1024
+
 .Linflated_image_size_offset:
 		.long	(input_data_end - 4) - .
 
@@ -1434,37 +1430,26 @@ reloc_code_end:
 
 #ifdef CONFIG_EFI_STUB
 ENTRY(efi_enter_kernel)
-		mov	r7, r0				@ preserve image base
-		mov	r4, r1				@ preserve DT pointer
+		mov	r4, r0			@ preserve image base
+		mov	r8, r1			@ preserve DT pointer
 
-		mov	r0, r4				@ DT start
-		add	r1, r4, r2			@ DT end
-		bl	cache_clean_flush
+		mrc	p15, 0, r0, c1, c0, 0	@ read SCTLR
+		tst	r0, #0x1		@ MMU enabled?
+		orreq	r4, r4, #1		@ set LSB if not
 
-		mov	r0, r7				@ relocated zImage
-		ldr	r1, =_edata			@ size of zImage
-		add	r1, r1, r0			@ end of zImage
+		mov	r0, r8			@ DT start
+		add	r1, r8, r2		@ DT end
 		bl	cache_clean_flush
 
-		@ The PE/COFF loader might not have cleaned the code we are
-		@ running beyond the PoU, and so calling cache_off below from
-		@ inside the PE/COFF loader allocated region is unsafe unless
-		@ we explicitly clean it to the PoC.
-		adr	r0, call_cache_fn		@ region of code we will
-		adr	r1, 0f				@ run with MMU off
-		bl	cache_clean_flush
-		bl	cache_off
+		adr	r0, 0f			@ switch to our stack
+		ldr	sp, [r0]
+		add	sp, sp, r0
 
-		@ Set parameters for booting zImage according to boot protocol
-		@ put FDT address in r2, it was returned by efi_entry()
-		@ r1 is the machine type, and r0 needs to be 0
-		mov	r0, #0
-		mov	r1, #0xFFFFFFFF
-		mov	r2, r4
-		add	r7, r7, #(__efi_start - start)
-		mov	pc, r7				@ no mode switch
+		mov	r5, #0			@ appended DTB size
+		mov	r7, #0xFFFFFFFF		@ machine ID
+		b	wont_overwrite
 ENDPROC(efi_enter_kernel)
-0:
+0:		.long	.L_user_stack_end - .
 #endif
 
 		.align
diff --git a/arch/arm/boot/compressed/vmlinux.lds.S b/arch/arm/boot/compressed/vmlinux.lds.S
index b247f399de71..d0619ec05705 100644
--- a/arch/arm/boot/compressed/vmlinux.lds.S
+++ b/arch/arm/boot/compressed/vmlinux.lds.S
@@ -63,9 +63,11 @@ SECTIONS
   _etext = .;
 
   .got.plt		: { *(.got.plt) }
+#ifndef CONFIG_EFI_STUB
   _got_start = .;
   .got			: { *(.got) }
   _got_end = .;
+#endif
 
   /* ensure the zImage file size is always a multiple of 64 bits */
   /* (without a dummy byte, ld just ignores the empty section) */
@@ -74,6 +76,9 @@ SECTIONS
 #ifdef CONFIG_EFI_STUB
   .data : ALIGN(4096) {
     __pecoff_data_start = .;
+    _got_start = .;
+    *(.got)
+    _got_end = .;
     /*
      * The EFI stub always executes from RAM, and runs strictly before the
      * decompressor, so we can make an exception for its r/w data, and keep it
diff --git a/drivers/firmware/efi/libstub/arm32-stub.c b/drivers/firmware/efi/libstub/arm32-stub.c
index 7826553af2ba..0050d811bf20 100644
--- a/drivers/firmware/efi/libstub/arm32-stub.c
+++ b/drivers/firmware/efi/libstub/arm32-stub.c
@@ -199,14 +199,8 @@ efi_status_t handle_kernel_image(unsigned long *image_addr,
 	unsigned long kernel_base;
 	efi_status_t status;
 
-	/*
-	 * Verify that the DRAM base address is compatible with the ARM
-	 * boot protocol, which determines the base of DRAM by masking
-	 * off the low 27 bits of the address at which the zImage is
-	 * loaded. These assumptions are made by the decompressor,
-	 * before any memory map is available.
-	 */
-	kernel_base = round_up(dram_base, SZ_128M);
+	/* use a 16 MiB aligned base for the decompressed kernel */
+	kernel_base = round_up(dram_base, SZ_16M) + TEXT_OFFSET;
 
 	/*
 	 * Note that some platforms (notably, the Raspberry Pi 2) put
@@ -215,41 +209,14 @@ efi_status_t handle_kernel_image(unsigned long *image_addr,
 	 * base of the kernel image is only partially used at the moment.
 	 * (Up to 5 pages are used for the swapper page tables)
 	 */
-	kernel_base += TEXT_OFFSET - 5 * PAGE_SIZE;
-
-	status = reserve_kernel_base(kernel_base, reserve_addr, reserve_size);
+	status = reserve_kernel_base(kernel_base - 5 * PAGE_SIZE, reserve_addr,
+				     reserve_size);
 	if (status != EFI_SUCCESS) {
 		pr_efi_err("Unable to allocate memory for uncompressed kernel.\n");
 		return status;
 	}
 
-	/*
-	 * Relocate the zImage, so that it appears in the lowest 128 MB
-	 * memory window.
-	 */
-	*image_addr = (unsigned long)image->image_base;
-	*image_size = image->image_size;
-	status = efi_relocate_kernel(image_addr, *image_size, *image_size,
-				     kernel_base + MAX_UNCOMP_KERNEL_SIZE, 0, 0);
-	if (status != EFI_SUCCESS) {
-		pr_efi_err("Failed to relocate kernel.\n");
-		efi_free(*reserve_size, *reserve_addr);
-		*reserve_size = 0;
-		return status;
-	}
-
-	/*
-	 * Check to see if we were able to allocate memory low enough
-	 * in memory. The kernel determines the base of DRAM from the
-	 * address at which the zImage is loaded.
-	 */
-	if (*image_addr + *image_size > dram_base + ZIMAGE_OFFSET_LIMIT) {
-		pr_efi_err("Failed to relocate kernel, no low memory available.\n");
-		efi_free(*reserve_size, *reserve_addr);
-		*reserve_size = 0;
-		efi_free(*image_size, *image_addr);
-		*image_size = 0;
-		return EFI_LOAD_ERROR;
-	}
+	*image_addr = kernel_base;
+	*image_size = 0;
 	return EFI_SUCCESS;
 }