x86, realmode: Move ACPI wakeup to unified realmode code

Migrated ACPI wakeup code to the real-mode blob.
Code existing in .x86_trampoline  can be completely
removed. Static descriptor table in wakeup_asm.S is
courtesy of H. Peter Anvin.

Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@intel.com>
Link: http://lkml.kernel.org/r/1336501366-28617-7-git-send-email-jarkko.sakkinen@intel.com
Cc: Rafael J. Wysocki <rjw@sisk.pl>
Cc: Len Brown <len.brown@intel.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>

15 files changed, 368 insertions, 0 deletions

diff --git a/arch/x86/realmode/rm/Makefile b/arch/x86/realmode/rm/Makefile
index 56ec64f94e69..2432acb6b04f 100644
--- a/arch/x86/realmode/rm/Makefile
+++ b/arch/x86/realmode/rm/Makefile
@@ -14,9 +14,13 @@ always := realmode.bin
 realmode-y                      += header.o
 realmode-$(CONFIG_X86_32)       += reboot_32.o
 realmode-y                      += trampoline_$(BITS).o
+realmode-$(CONFIG_ACPI_SLEEP)   += wakeup/wakeup.o
 
 targets += $(realmode-y)
 
+$(obj)/wakeup/wakeup.o: FORCE
+        $(Q)$(MAKE) $(build)=$(obj)/wakeup $@
+
 REALMODE_OBJS = $(addprefix $(obj)/,$(realmode-y))
 
 sed-pasyms := -n -r -e 's/^([0-9a-fA-F]+) [ABCDGRSTVW] (.+)$$/pa_\2 = \2;/p'
diff --git a/arch/x86/realmode/rm/header.S b/arch/x86/realmode/rm/header.S
index a97900409c61..730b1316c099 100644
--- a/arch/x86/realmode/rm/header.S
+++ b/arch/x86/realmode/rm/header.S
@@ -27,4 +27,9 @@ ENTRY(real_mode_header)
                 .long   pa_level3_ident_pgt
                 .long   pa_level3_kernel_pgt
 #endif
+                /* ACPI sleep */
+#ifdef CONFIG_ACPI_SLEEP
+                .long   pa_wakeup_start
+                .long   pa_wakeup_header
+#endif
 END(real_mode_header)
diff --git a/arch/x86/realmode/rm/realmode.lds.S b/arch/x86/realmode/rm/realmode.lds.S
index c5b8a4f31ba3..91b83ea55c37 100644
--- a/arch/x86/realmode/rm/realmode.lds.S
+++ b/arch/x86/realmode/rm/realmode.lds.S
@@ -25,6 +25,10 @@ SECTIONS
         .rodata : {
                 *(.rodata)
                 *(.rodata.*)
+                . = ALIGN(16);
+                video_cards = .;
+                *(.videocards)
+                video_cards_end = .;
         }
 
         . = ALIGN(PAGE_SIZE);
diff --git a/arch/x86/realmode/rm/wakeup/.gitignore b/arch/x86/realmode/rm/wakeup/.gitignore
new file mode 100644
index 000000000000..58f1f48a58f8
--- /dev/null
+++ b/arch/x86/realmode/rm/wakeup/.gitignore
@@ -0,0 +1,3 @@
+wakeup.bin
+wakeup.elf
+wakeup.lds
diff --git a/arch/x86/realmode/rm/wakeup/Makefile b/arch/x86/realmode/rm/wakeup/Makefile
new file mode 100644
index 000000000000..4c8533240cdd
--- /dev/null
+++ b/arch/x86/realmode/rm/wakeup/Makefile
@@ -0,0 +1,33 @@
+#
+# arch/x86/kernel/acpi/realmode/Makefile
+#
+# This file is subject to the terms and conditions of the GNU General Public
+# License.  See the file "COPYING" in the main directory of this archive
+# for more details.
+#
+
+always          := wakeup.o
+
+wakeup-y        += wakeup_asm.o wakemain.o video-mode.o
+wakeup-y        += copy.o bioscall.o regs.o
+
+# The link order of the video-*.o modules can matter.  In particular,
+# video-vga.o *must* be listed first, followed by video-vesa.o.
+# Hardware-specific drivers should follow in the order they should be
+# probed, and video-bios.o should typically be last.
+wakeup-y        += video-vga.o
+wakeup-y        += video-vesa.o
+wakeup-y        += video-bios.o
+
+targets         += $(wakeup-y)
+
+WAKEUP_OBJS = $(addprefix $(obj)/,$(wakeup-y))
+
+LDFLAGS_wakeup.o := -m elf_i386 -r
+$(obj)/wakeup.o: $(WAKEUP_OBJS) FORCE
+        $(call if_changed,ld)
+
+bootsrc := $(src)/../../../boot
+
+ccflags-y += -D_WAKEUP -I$(srctree)/$(bootsrc)
+asflags-y += -D_WAKEUP -I$(srctree)/$(bootsrc)
diff --git a/arch/x86/realmode/rm/wakeup/bioscall.S b/arch/x86/realmode/rm/wakeup/bioscall.S
new file mode 100644
index 000000000000..f51eb0bb56ce
--- /dev/null
+++ b/arch/x86/realmode/rm/wakeup/bioscall.S
@@ -0,0 +1 @@
+#include "../../../boot/bioscall.S"
diff --git a/arch/x86/realmode/rm/wakeup/copy.S b/arch/x86/realmode/rm/wakeup/copy.S
new file mode 100644
index 000000000000..dc59ebee69d8
--- /dev/null
+++ b/arch/x86/realmode/rm/wakeup/copy.S
@@ -0,0 +1 @@
+#include "../../../boot/copy.S"
diff --git a/arch/x86/realmode/rm/wakeup/regs.c b/arch/x86/realmode/rm/wakeup/regs.c
new file mode 100644
index 000000000000..6206033ba202
--- /dev/null
+++ b/arch/x86/realmode/rm/wakeup/regs.c
@@ -0,0 +1 @@
+#include "../../../boot/regs.c"
diff --git a/arch/x86/realmode/rm/wakeup/video-bios.c b/arch/x86/realmode/rm/wakeup/video-bios.c
new file mode 100644
index 000000000000..7deabc144a27
--- /dev/null
+++ b/arch/x86/realmode/rm/wakeup/video-bios.c
@@ -0,0 +1 @@
+#include "../../../boot/video-bios.c"
diff --git a/arch/x86/realmode/rm/wakeup/video-mode.c b/arch/x86/realmode/rm/wakeup/video-mode.c
new file mode 100644
index 000000000000..328ad209f113
--- /dev/null
+++ b/arch/x86/realmode/rm/wakeup/video-mode.c
@@ -0,0 +1 @@
+#include "../../../boot/video-mode.c"
diff --git a/arch/x86/realmode/rm/wakeup/video-vesa.c b/arch/x86/realmode/rm/wakeup/video-vesa.c
new file mode 100644
index 000000000000..9dbb9672226a
--- /dev/null
+++ b/arch/x86/realmode/rm/wakeup/video-vesa.c
@@ -0,0 +1 @@
+#include "../../../boot/video-vesa.c"
diff --git a/arch/x86/realmode/rm/wakeup/video-vga.c b/arch/x86/realmode/rm/wakeup/video-vga.c
new file mode 100644
index 000000000000..bcc81255f374
--- /dev/null
+++ b/arch/x86/realmode/rm/wakeup/video-vga.c
@@ -0,0 +1 @@
+#include "../../../boot/video-vga.c"
diff --git a/arch/x86/realmode/rm/wakeup/wakemain.c b/arch/x86/realmode/rm/wakeup/wakemain.c
new file mode 100644
index 000000000000..91405d515ec6
--- /dev/null
+++ b/arch/x86/realmode/rm/wakeup/wakemain.c
@@ -0,0 +1,82 @@
+#include "wakeup.h"
+#include "boot.h"
+
+static void udelay(int loops)
+{
+        while (loops--)
+                io_delay();     /* Approximately 1 us */
+}
+
+static void beep(unsigned int hz)
+{
+        u8 enable;
+
+        if (!hz) {
+                enable = 0x00;          /* Turn off speaker */
+        } else {
+                u16 div = 1193181/hz;
+
+                outb(0xb6, 0x43);       /* Ctr 2, squarewave, load, binary */
+                io_delay();
+                outb(div, 0x42);        /* LSB of counter */
+                io_delay();
+                outb(div >> 8, 0x42);   /* MSB of counter */
+                io_delay();
+
+                enable = 0x03;          /* Turn on speaker */
+        }
+        inb(0x61);              /* Dummy read of System Control Port B */
+        io_delay();
+        outb(enable, 0x61);     /* Enable timer 2 output to speaker */
+        io_delay();
+}
+
+#define DOT_HZ          880
+#define DASH_HZ         587
+#define US_PER_DOT      125000
+
+/* Okay, this is totally silly, but it's kind of fun. */
+static void send_morse(const char *pattern)
+{
+        char s;
+
+        while ((s = *pattern++)) {
+                switch (s) {
+                case '.':
+                        beep(DOT_HZ);
+                        udelay(US_PER_DOT);
+                        beep(0);
+                        udelay(US_PER_DOT);
+                        break;
+                case '-':
+                        beep(DASH_HZ);
+                        udelay(US_PER_DOT * 3);
+                        beep(0);
+                        udelay(US_PER_DOT);
+                        break;
+                default:        /* Assume it's a space */
+                        udelay(US_PER_DOT * 3);
+                        break;
+                }
+        }
+}
+
+void main(void)
+{
+        /* Kill machine if structures are wrong */
+        if (wakeup_header.real_magic != 0x12345678)
+                while (1)
+                        ;
+
+        if (wakeup_header.realmode_flags & 4)
+                send_morse("...-");
+
+        if (wakeup_header.realmode_flags & 1)
+                asm volatile("lcallw   $0xc000,$3");
+
+        if (wakeup_header.realmode_flags & 2) {
+                /* Need to call BIOS */
+                probe_cards(0);
+                set_mode(wakeup_header.video_mode);
+        }
+}
diff --git a/arch/x86/realmode/rm/wakeup/wakeup.h b/arch/x86/realmode/rm/wakeup/wakeup.h
new file mode 100644
index 000000000000..2dfaf06b8af1
--- /dev/null
+++ b/arch/x86/realmode/rm/wakeup/wakeup.h
@@ -0,0 +1,41 @@
+/*
+ * Definitions for the wakeup data structure at the head of the
+ * wakeup code.
+ */
+
+#ifndef ARCH_X86_KERNEL_ACPI_RM_WAKEUP_H
+#define ARCH_X86_KERNEL_ACPI_RM_WAKEUP_H
+
+#ifndef __ASSEMBLY__
+#include <linux/types.h>
+
+/* This must match data at wakeup.S */
+struct wakeup_header {
+        u16 video_mode;         /* Video mode number */
+        u32 pmode_entry;        /* Protected mode resume point, 32-bit only */
+        u16 pmode_cs;
+        u32 pmode_cr0;          /* Protected mode cr0 */
+        u32 pmode_cr3;          /* Protected mode cr3 */
+        u32 pmode_cr4;          /* Protected mode cr4 */
+        u32 pmode_efer_low;     /* Protected mode EFER */
+        u32 pmode_efer_high;
+        u64 pmode_gdt;
+        u32 pmode_misc_en_low;  /* Protected mode MISC_ENABLE */
+        u32 pmode_misc_en_high;
+        u32 pmode_behavior;     /* Wakeup routine behavior flags */
+        u32 realmode_flags;
+        u32 real_magic;
+        u32 signature;          /* To check we have correct structure */
+} __attribute__((__packed__));
+
+extern struct wakeup_header wakeup_header;
+#endif
+
+#define WAKEUP_HEADER_OFFSET    8
+#define WAKEUP_HEADER_SIGNATURE 0x51ee1111
+#define WAKEUP_END_SIGNATURE    0x65a22c82
+
+/* Wakeup behavior bits */
+#define WAKEUP_BEHAVIOR_RESTORE_MISC_ENABLE     0
+
+#endif /* ARCH_X86_KERNEL_ACPI_RM_WAKEUP_H */
diff --git a/arch/x86/realmode/rm/wakeup/wakeup_asm.S b/arch/x86/realmode/rm/wakeup/wakeup_asm.S
new file mode 100644
index 000000000000..b61126cb599e
--- /dev/null
+++ b/arch/x86/realmode/rm/wakeup/wakeup_asm.S
@@ -0,0 +1,189 @@
+/*
+ * ACPI wakeup real mode startup stub
+ */
+#include <asm/segment.h>
+#include <asm/msr-index.h>
+#include <asm/page_types.h>
+#include <asm/pgtable_types.h>
+#include <asm/processor-flags.h>
+#include "wakeup.h"
+
+                .code16
+
+/* This should match the structure in wakeup.h */
+                .section ".data", "aw"
+                .globl  wakeup_header
+wakeup_header:
+video_mode:     .short  0       /* Video mode number */
+pmode_entry:    .long   0
+pmode_cs:       .short  __KERNEL_CS
+pmode_cr0:      .long   0       /* Saved %cr0 */
+pmode_cr3:      .long   0       /* Saved %cr3 */
+pmode_cr4:      .long   0       /* Saved %cr4 */
+pmode_efer:     .quad   0       /* Saved EFER */
+pmode_gdt:      .quad   0
+pmode_misc_en:  .quad   0       /* Saved MISC_ENABLE MSR */
+pmode_behavior: .long   0       /* Wakeup behavior flags */
+realmode_flags: .long   0
+real_magic:     .long   0
+signature:      .long   WAKEUP_HEADER_SIGNATURE
+                .size   wakeup_header, .-wakeup_header
+
+        .text
+        .code16
+        .globl  wakeup_start
+wakeup_start:
+        cli
+        cld
+
+        .byte   0xea            /* ljmpw */
+        .word   3f
+        .word   real_mode_seg
+3:
+        /* Apparently some dimwit BIOS programmers don't know how to
+           program a PM to RM transition, and we might end up here with
+           junk in the data segment descriptor registers.  The only way
+           to repair that is to go into PM and fix it ourselves... */
+        movw    $16, %cx
+        lgdtl   %cs:wakeup_gdt
+        movl    %cr0, %eax
+        orb     $X86_CR0_PE, %al
+        movl    %eax, %cr0
+        ljmpw   $8, $2f
+2:
+        movw    %cx, %ds
+        movw    %cx, %es
+        movw    %cx, %ss
+        movw    %cx, %fs
+        movw    %cx, %gs
+
+        andb    $~X86_CR0_PE, %al
+        movl    %eax, %cr0
+        .byte   0xea            /* ljmpw */
+        .word   3f
+        .word   real_mode_seg
+3:
+        /* Set up segments */
+        movw    %cs, %ax
+        movw    %ax, %ds
+        movw    %ax, %es
+        movw    %ax, %ss
+        lidtl   wakeup_idt
+
+        movl    $wakeup_stack_end, %esp
+
+        /* Clear the EFLAGS */
+        pushl   $0
+        popfl
+
+        /* Check header signature... */
+        movl    signature, %eax
+        cmpl    $WAKEUP_HEADER_SIGNATURE, %eax
+        jne     bogus_real_magic
+
+        /* Check we really have everything... */
+        movl    end_signature, %eax
+        cmpl    $WAKEUP_END_SIGNATURE, %eax
+        jne     bogus_real_magic
+
+        /* Call the C code */
+        calll   main
+
+        /* Restore MISC_ENABLE before entering protected mode, in case
+           BIOS decided to clear XD_DISABLE during S3. */
+        movl    pmode_behavior, %eax
+        btl     $WAKEUP_BEHAVIOR_RESTORE_MISC_ENABLE, %eax
+        jnc     1f
+
+        movl    pmode_misc_en, %eax
+        movl    pmode_misc_en + 4, %edx
+        movl    $MSR_IA32_MISC_ENABLE, %ecx
+        wrmsr
+1:
+
+        /* Do any other stuff... */
+
+#ifndef CONFIG_64BIT
+        /* This could also be done in C code... */
+        movl    pmode_cr3, %eax
+        movl    %eax, %cr3
+
+        movl    pmode_cr4, %ecx
+        jecxz   1f
+        movl    %ecx, %cr4
+1:
+        movl    pmode_efer, %eax
+        movl    pmode_efer + 4, %edx
+        movl    %eax, %ecx
+        orl     %edx, %ecx
+        jz      1f
+        movl    $MSR_EFER, %ecx
+        wrmsr
+1:
+
+        lgdtl   pmode_gdt
+
+        /* This really couldn't... */
+        movl    pmode_cr0, %eax
+        movl    %eax, %cr0
+        ljmpl   *pmode_entry
+#else
+        jmp     trampoline_data
+#endif
+
+bogus_real_magic:
+1:
+        hlt
+        jmp     1b
+
+        .section ".rodata","a"
+
+        /*
+         * Set up the wakeup GDT.  We set these up as Big Real Mode,
+         * that is, with limits set to 4 GB.  At least the Lenovo
+         * Thinkpad X61 is known to need this for the video BIOS
+         * initialization quirk to work; this is likely to also
+         * be the case for other laptops or integrated video devices.
+         */
+
+        .globl  wakeup_gdt
+        .balign 16
+wakeup_gdt:
+        .word   3*8-1           /* Self-descriptor */
+        .long   pa_wakeup_gdt
+        .word   0
+
+        .word   0xffff          /* 16-bit code segment @ real_mode_base */
+        .long   0x9b000000 + pa_real_mode_base
+        .word   0x008f          /* big real mode */
+
+        .word   0xffff          /* 16-bit data segment @ real_mode_base */
+        .long   0x93000000 + pa_real_mode_base
+        .word   0x008f          /* big real mode */
+        .size   wakeup_gdt, .-wakeup_gdt
+
+        .data
+        .balign 8
+
+        /* This is the standard real-mode IDT */
+wakeup_idt:
+        .word   0xffff          /* limit */
+        .long   0               /* address */
+        .word   0
+
+        .globl  HEAP, heap_end
+HEAP:
+        .long   wakeup_heap
+heap_end:
+        .long   wakeup_stack
+
+        .bss
+wakeup_heap:
+        .space  2048
+wakeup_stack:
+        .space  2048
+wakeup_stack_end:
+
+        .section ".signature","a"
+end_signature:
+        .long   WAKEUP_END_SIGNATURE