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 56ec64f..2432acb 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 a979004..730b131 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 c5b8a4f..91b83ea 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 0000000..58f1f48
--- /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 0000000..4c85332
--- /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 0000000..f51eb0b
--- /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 0000000..dc59ebe
--- /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 0000000..6206033
--- /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 0000000..7deabc1
--- /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 0000000..328ad20
--- /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 0000000..9dbb967
--- /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 0000000..bcc8125
--- /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 0000000..91405d5
--- /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 0000000..2dfaf06
--- /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 0000000..b61126c
--- /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