x86, trampoline: Use the unified trampoline setup for ACPI wakeup

Use the unified trampoline allocation setup to allocate and install
the ACPI wakeup code in low memory.

Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
LKML-Reference: <4D5DFBE4.7090104@intel.com>
Cc: Rafael J. Wysocki <rjw@sisk.pl>
Cc: Matthieu Castet <castet.matthieu@free.fr>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>

9 files changed, 68 insertions, 108 deletions

diff --git a/arch/x86/include/asm/acpi.h b/arch/x86/include/asm/acpi.h
index 211ca3f7fd16..4784df504d28 100644
--- a/arch/x86/include/asm/acpi.h
+++ b/arch/x86/include/asm/acpi.h
@@ -29,6 +29,7 @@
 #include <asm/processor.h>
 #include <asm/mmu.h>
 #include <asm/mpspec.h>
+#include <asm/trampoline.h>
 
 #define COMPILER_DEPENDENT_INT64   long long
 #define COMPILER_DEPENDENT_UINT64  unsigned long long
@@ -116,7 +117,8 @@ static inline void acpi_disable_pci(void)
 extern int acpi_save_state_mem(void);
 extern void acpi_restore_state_mem(void);
 
-extern unsigned long acpi_wakeup_address;
+extern const unsigned char acpi_wakeup_code[];
+#define acpi_wakeup_address (__pa(TRAMPOLINE_SYM(acpi_wakeup_code)))
 
 /* early initialization routine */
 extern void acpi_reserve_wakeup_memory(void);
diff --git a/arch/x86/include/asm/trampoline.h b/arch/x86/include/asm/trampoline.h
index f4500fb3b485..feca3118a73b 100644
--- a/arch/x86/include/asm/trampoline.h
+++ b/arch/x86/include/asm/trampoline.h
@@ -3,25 +3,36 @@
 
 #ifndef __ASSEMBLY__
 
-#ifdef CONFIG_X86_TRAMPOLINE
+#include <linux/types.h>
+#include <asm/io.h>
+
 /*
- * Trampoline 80x86 program as an array.
+ * Trampoline 80x86 program as an array.  These are in the init rodata
+ * segment, but that's okay, because we only care about the relative
+ * addresses of the symbols.
  */
-extern const unsigned char trampoline_data [];
-extern const unsigned char trampoline_end  [];
-extern unsigned char *trampoline_base;
+extern const unsigned char x86_trampoline_start [];
+extern const unsigned char x86_trampoline_end   [];
+extern unsigned char *x86_trampoline_base;
 
 extern unsigned long init_rsp;
 extern unsigned long initial_code;
 extern unsigned long initial_gs;
 
-#define TRAMPOLINE_SIZE roundup(trampoline_end - trampoline_data, PAGE_SIZE)
+extern void __init setup_trampolines(void);
+
+extern const unsigned char trampoline_data[];
+extern const unsigned char trampoline_status[];
+
+#define TRAMPOLINE_SYM(x)                                               \
+        ((void *)(x86_trampoline_base +                                 \
+                  ((const unsigned char *)(x) - x86_trampoline_start)))
 
-extern unsigned long setup_trampoline(void);
-extern void __init reserve_trampoline_memory(void);
-#else
-static inline void reserve_trampoline_memory(void) {}
-#endif /* CONFIG_X86_TRAMPOLINE */
+/* Address of the SMP trampoline */
+static inline unsigned long trampoline_address(void)
+{
+        return virt_to_phys(TRAMPOLINE_SYM(trampoline_data));
+}
 
 #endif /* __ASSEMBLY__ */
 
diff --git a/arch/x86/kernel/acpi/realmode/wakeup.S b/arch/x86/kernel/acpi/realmode/wakeup.S
index 28595d6df47c..ead21b663117 100644
--- a/arch/x86/kernel/acpi/realmode/wakeup.S
+++ b/arch/x86/kernel/acpi/realmode/wakeup.S
@@ -6,11 +6,17 @@
 #include <asm/page_types.h>
 #include <asm/pgtable_types.h>
 #include <asm/processor-flags.h>
+#include "wakeup.h"
 
         .code16
-        .section ".header", "a"
+        .section ".jump", "ax"
+        .globl  _start
+_start:
+        cli
+        jmp     wakeup_code
 
 /* This should match the structure in wakeup.h */
+                .section ".header", "a"
                 .globl  wakeup_header
 wakeup_header:
 video_mode:     .short  0       /* Video mode number */
@@ -30,14 +36,11 @@ wakeup_jmp:	.byte	0xea	/* ljmpw */
 wakeup_jmp_off: .word   3f
 wakeup_jmp_seg: .word   0
 wakeup_gdt:     .quad   0, 0, 0
-signature:      .long   0x51ee1111
+signature:      .long   WAKEUP_HEADER_SIGNATURE
 
         .text
-        .globl  _start
         .code16
 wakeup_code:
-_start:
-        cli
         cld
 
         /* Apparently some dimwit BIOS programmers don't know how to
@@ -77,12 +80,12 @@ _start:
 
         /* Check header signature... */
         movl    signature, %eax
-        cmpl    $0x51ee1111, %eax
+        cmpl    $WAKEUP_HEADER_SIGNATURE, %eax
         jne     bogus_real_magic
 
         /* Check we really have everything... */
         movl    end_signature, %eax
-        cmpl    $0x65a22c82, %eax
+        cmpl    $WAKEUP_END_SIGNATURE, %eax
         jne     bogus_real_magic
 
         /* Call the C code */
@@ -147,3 +150,7 @@ wakeup_heap:
 wakeup_stack:
         .space  2048
 wakeup_stack_end:
+
+        .section ".signature","a"
+end_signature:
+        .long   WAKEUP_END_SIGNATURE
diff --git a/arch/x86/kernel/acpi/realmode/wakeup.h b/arch/x86/kernel/acpi/realmode/wakeup.h
index 69d38d0b2b64..e1828c07e79c 100644
--- a/arch/x86/kernel/acpi/realmode/wakeup.h
+++ b/arch/x86/kernel/acpi/realmode/wakeup.h
@@ -35,7 +35,8 @@ struct wakeup_header {
 extern struct wakeup_header wakeup_header;
 #endif
 
-#define HEADER_OFFSET 0x3f00
-#define WAKEUP_SIZE   0x4000
+#define WAKEUP_HEADER_OFFSET    8
+#define WAKEUP_HEADER_SIGNATURE 0x51ee1111
+#define WAKEUP_END_SIGNATURE    0x65a22c82
 
 #endif /* ARCH_X86_KERNEL_ACPI_RM_WAKEUP_H */
diff --git a/arch/x86/kernel/acpi/realmode/wakeup.lds.S b/arch/x86/kernel/acpi/realmode/wakeup.lds.S
index 060fff8f5c5b..d4f8010a5b1b 100644
--- a/arch/x86/kernel/acpi/realmode/wakeup.lds.S
+++ b/arch/x86/kernel/acpi/realmode/wakeup.lds.S
@@ -13,9 +13,19 @@ ENTRY(_start)
 SECTIONS
 {
         . = 0;
+        .jump   : {
+                *(.jump)
+        } = 0x90909090
+
+        . = WAKEUP_HEADER_OFFSET;
+        .header : {
+                *(.header)
+        }
+
+        . = ALIGN(16);
         .text : {
                  *(.text*)
-        }
+        } = 0x90909090
 
         . = ALIGN(16);
         .rodata : {
@@ -33,11 +43,6 @@ SECTIONS
                  *(.data*)
         }
 
-        .signature : {
-                end_signature = .;
-                LONG(0x65a22c82)
-        }
-
         . = ALIGN(16);
         .bss :  {
                 __bss_start = .;
@@ -45,20 +50,13 @@ SECTIONS
                 __bss_end = .;
         }
 
-        . = HEADER_OFFSET;
-        .header : {
-                *(.header)
+        .signature : {
+                *(.signature)
         }
 
-        . = ALIGN(16);
         _end = .;
 
         /DISCARD/ : {
                 *(.note*)
         }
-
-        /*
-         * The ASSERT() sink to . is intentional, for binutils 2.14 compatibility:
-         */
-        . = ASSERT(_end <= WAKEUP_SIZE, "Wakeup too big!");
 }
diff --git a/arch/x86/kernel/acpi/sleep.c b/arch/x86/kernel/acpi/sleep.c
index 68d1537b8c81..4572c58e66d5 100644
--- a/arch/x86/kernel/acpi/sleep.c
+++ b/arch/x86/kernel/acpi/sleep.c
@@ -18,12 +18,8 @@
 #include "realmode/wakeup.h"
 #include "sleep.h"
 
-unsigned long acpi_wakeup_address;
 unsigned long acpi_realmode_flags;
 
-/* address in low memory of the wakeup routine. */
-static unsigned long acpi_realmode;
-
 #if defined(CONFIG_SMP) && defined(CONFIG_64BIT)
 static char temp_stack[4096];
 #endif
@@ -33,22 +29,17 @@ static char temp_stack[4096];
  *
  * Create an identity mapped page table and copy the wakeup routine to
  * low memory.
- *
- * Note that this is too late to change acpi_wakeup_address.
  */
 int acpi_save_state_mem(void)
 {
         struct wakeup_header *header;
+        /* address in low memory of the wakeup routine. */
+        char *acpi_realmode;
 
-        if (!acpi_realmode) {
-                printk(KERN_ERR "Could not allocate memory during boot, "
-                       "S3 disabled\n");
-                return -ENOMEM;
-        }
-        memcpy((void *)acpi_realmode, &wakeup_code_start, WAKEUP_SIZE);
+        acpi_realmode = TRAMPOLINE_SYM(acpi_wakeup_code);
 
-        header = (struct wakeup_header *)(acpi_realmode + HEADER_OFFSET);
-        if (header->signature != 0x51ee1111) {
+        header = (struct wakeup_header *)(acpi_realmode + WAKEUP_HEADER_OFFSET);
+        if (header->signature != WAKEUP_HEADER_SIGNATURE) {
                 printk(KERN_ERR "wakeup header does not match\n");
                 return -EINVAL;
         }
@@ -68,9 +59,7 @@ int acpi_save_state_mem(void)
         /* GDT[0]: GDT self-pointer */
         header->wakeup_gdt[0] =
                 (u64)(sizeof(header->wakeup_gdt) - 1) +
-                ((u64)(acpi_wakeup_address +
-                        ((char *)&header->wakeup_gdt - (char *)acpi_realmode))
-                                << 16);
+                ((u64)__pa(&header->wakeup_gdt) << 16);
         /* GDT[1]: big real mode-like code segment */
         header->wakeup_gdt[1] =
                 GDT_ENTRY(0x809b, acpi_wakeup_address, 0xfffff);
@@ -96,7 +85,7 @@ int acpi_save_state_mem(void)
         header->pmode_cr3 = (u32)__pa(&initial_page_table);
         saved_magic = 0x12345678;
 #else /* CONFIG_64BIT */
-        header->trampoline_segment = setup_trampoline() >> 4;
+        header->trampoline_segment = trampoline_address() >> 4;
 #ifdef CONFIG_SMP
         stack_start = (unsigned long)temp_stack + sizeof(temp_stack);
         early_gdt_descr.address =
@@ -117,46 +106,6 @@ void acpi_restore_state_mem(void)
 {
 }
 
-
-/**
- * acpi_reserve_wakeup_memory - do _very_ early ACPI initialisation
- *
- * We allocate a page from the first 1MB of memory for the wakeup
- * routine for when we come back from a sleep state. The
- * runtime allocator allows specification of <16MB pages, but not
- * <1MB pages.
- */
-void __init acpi_reserve_wakeup_memory(void)
-{
-        phys_addr_t mem;
-
-        if ((&wakeup_code_end - &wakeup_code_start) > WAKEUP_SIZE) {
-                printk(KERN_ERR
-                       "ACPI: Wakeup code way too big, S3 disabled.\n");
-                return;
-        }
-
-        mem = memblock_find_in_range(0, 1<<20, WAKEUP_SIZE, PAGE_SIZE);
-
-        if (mem == MEMBLOCK_ERROR) {
-                printk(KERN_ERR "ACPI: Cannot allocate lowmem, S3 disabled.\n");
-                return;
-        }
-        acpi_realmode = (unsigned long) phys_to_virt(mem);
-        acpi_wakeup_address = mem;
-        memblock_x86_reserve_range(mem, mem + WAKEUP_SIZE, "ACPI WAKEUP");
-}
-
-int __init acpi_configure_wakeup_memory(void)
-{
-        if (acpi_realmode)
-                set_memory_x(acpi_realmode, WAKEUP_SIZE >> PAGE_SHIFT);
-
-        return 0;
-}
-arch_initcall(acpi_configure_wakeup_memory);
-
-
 static int __init acpi_sleep_setup(char *str)
 {
         while ((str != NULL) && (*str != '\0')) {
diff --git a/arch/x86/kernel/acpi/sleep.h b/arch/x86/kernel/acpi/sleep.h
index adbcbaa6f1df..86ba1c87165b 100644
--- a/arch/x86/kernel/acpi/sleep.h
+++ b/arch/x86/kernel/acpi/sleep.h
@@ -4,13 +4,10 @@
 
 #include <asm/trampoline.h>
 
-extern char wakeup_code_start, wakeup_code_end;
-
 extern unsigned long saved_video_mode;
 extern long saved_magic;
 
 extern int wakeup_pmode_return;
-extern char swsusp_pg_dir[PAGE_SIZE];
 
 extern unsigned long acpi_copy_wakeup_routine(unsigned long);
 extern void wakeup_long64(void);
diff --git a/arch/x86/kernel/acpi/wakeup_rm.S b/arch/x86/kernel/acpi/wakeup_rm.S
index 6ff3b5730575..6ce81ee9cb03 100644
--- a/arch/x86/kernel/acpi/wakeup_rm.S
+++ b/arch/x86/kernel/acpi/wakeup_rm.S
@@ -2,9 +2,11 @@
  * Wrapper script for the realmode binary as a transport object
  * before copying to low memory.
  */
-        .section ".rodata","a"
-        .globl  wakeup_code_start, wakeup_code_end
-wakeup_code_start:
+#include <asm/page_types.h>
+
+        .section ".x86_trampoline","a"
+        .balign PAGE_SIZE
+        .globl  acpi_wakeup_code
+acpi_wakeup_code:
         .incbin "arch/x86/kernel/acpi/realmode/wakeup.bin"
-wakeup_code_end:
         .size   wakeup_code_start, .-wakeup_code_start
diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c
index 994ea20e177c..a089fc19ffae 100644
--- a/arch/x86/kernel/setup.c
+++ b/arch/x86/kernel/setup.c
@@ -937,13 +937,6 @@ void __init setup_arch(char **cmdline_p)
 
         setup_trampolines();
 
-#ifdef CONFIG_ACPI_SLEEP
-        /*
-         * Reserve low memory region for sleep support.
-         * even before init_memory_mapping
-         */
-        acpi_reserve_wakeup_memory();
-#endif
         init_gbpages();
 
         /* max_pfn_mapped is updated here */