From mboxrd@z Thu Jan 1 00:00:00 1970 From: ole.rohne-vJEk5272eHo@public.gmane.org Subject: Radeon S3/resume: VGA ROM POST from kernel Date: 19 Jul 2004 11:31:36 +0200 Sender: acpi-devel-admin-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org Message-ID: References: Mime-Version: 1.0 Content-Type: multipart/mixed; boundary="=-=-=" Return-path: In-Reply-To: Errors-To: acpi-devel-admin-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , List-Archive: To: acpi-devel-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org Cc: aman-e31a5gnSYeGubukWoKzokaxOck334EZe@public.gmane.org, stefandoesinger-RbZlAiThDcE@public.gmane.org, emmanuel.thome-/zGXu1G9BXs@public.gmane.org, software-v2/BnvaKusE@public.gmane.org List-Id: linux-acpi@vger.kernel.org --=-=-= I've implemented VGA POSTing using a real-mode tunnel from kernel space. IMO, this has some advantages over user space methods: 1. It works with the aty/radeon_pm.c resume code. I don't see how to easily achieve this with user space methods. 2. Real mode seems faster than userspace vm86 3. It is the right way. Bringing up the hardware is clearly the responsibility of the kernel/drivers resume code. Ole --=-=-= Content-Disposition: attachment; filename=patch-2.6.7-p2120 Content-Description: patch diff -ru -X dontdiff linux-2.6.7/arch/i386/kernel/acpi/sleep.c linux-2.6.7-p2120/arch/i386/kernel/acpi/sleep.c --- linux-2.6.7/arch/i386/kernel/acpi/sleep.c 2004-07-06 21:48:04.000000000 +0200 +++ linux-2.6.7-p2120/arch/i386/kernel/acpi/sleep.c 2004-07-19 10:53:48.000000000 +0200 @@ -5,6 +5,7 @@ * Copyright (C) 2001-2003 Pavel Machek */ +#include #include #include #include @@ -63,6 +64,31 @@ zap_low_mappings(); } +/* + * acpi_vgapost + */ + +extern void do_vgapost_lowlevel (unsigned long); + +void acpi_vgapost (unsigned long slot) +{ + unsigned long flags, saved_video_flags = acpi_video_flags; + acpi_video_flags = (slot & 0xffff) << 16 | 1; + /* Map low memory and copy information */ + init_low_mapping(swapper_pg_dir, USER_PTRS_PER_PGD); + memcpy((void *) acpi_wakeup_address, &wakeup_start, &wakeup_end - &wakeup_start); + acpi_copy_wakeup_routine(acpi_wakeup_address); + /* Tunnel thru real mode */ + local_irq_save(flags); + do_vgapost_lowlevel(acpi_wakeup_address); + local_irq_restore(flags); + /* Restore mapping etc */ + zap_low_mappings(); + acpi_video_flags = saved_video_flags; +} + +EXPORT_SYMBOL (acpi_vgapost); + /** * acpi_reserve_bootmem - do _very_ early ACPI initialisation * diff -ru -X dontdiff linux-2.6.7/arch/i386/kernel/acpi/wakeup.S linux-2.6.7-p2120/arch/i386/kernel/acpi/wakeup.S --- linux-2.6.7/arch/i386/kernel/acpi/wakeup.S 2004-07-05 19:37:21.000000000 +0200 +++ linux-2.6.7-p2120/arch/i386/kernel/acpi/wakeup.S 2004-07-19 11:02:30.000000000 +0200 @@ -43,6 +43,7 @@ testl $1, video_flags - wakeup_code jz 1f + movw video_flags - wakeup_code + 2, %ax lcall $0xc000,$3 movw %cs, %ax movw %ax, %ds # Bios might have played with that @@ -159,6 +160,32 @@ _setbad: jmp setbad +# +# Real mode switch - verbatim from reboot.c +# +go_real: + movl %cr0, %eax + andl $0x00000011, %eax + orl $0x60000000, %eax + movl %eax, %cr0 + movl %eax, %cr3 + movl %cr0, %ebx + andl $0x60000000, %ebx + jz 1f + wbinvd +1: andb $0x10, %al + movl %eax, %cr0 +go_real_jmp: .byte 0xea +go_real_jmp_off: .word 0x0000 +go_real_jmp_seg: .word 0x0000 +# +# Real mode descriptor table +# + .align 8 +go_real_desc: .quad 0x0000000000000000 +go_real_cseg: .quad 0x00009a000000ffff +go_real_dseg: .quad 0x000092000000ffff + .code32 ALIGN @@ -284,6 +311,59 @@ call acpi_enter_sleep_state_s4bios ret +ENTRY(do_vgapost_lowlevel) + # Convert target offset to physical address + movl %eax, %ecx + subl $__PAGE_OFFSET, %ecx + # Fixup GDT pointer + movl %ecx, %edx + addl $go_real_desc - wakeup_start, %edx + movl %edx, go_real_gdt + 2 + # Fixup 16-bit CS descriptor + movl %ecx, %edx + movw %dx, go_real_cseg - wakeup_start + 2 (%eax) + shrl $16, %edx + movb %dl, go_real_cseg - wakeup_start + 4 (%eax) + movb %dh, go_real_cseg - wakeup_start + 7 (%eax) + # Fixup 16-bit jump + movl %ecx, %edx + shrl $4, %edx + movw %dx, go_real_jmp_seg - wakeup_start (%eax) + # Save state and registers + call save_processor_state + call save_registers + # Reload page table with low mapping + movl $swapper_pg_dir-__PAGE_OFFSET, %eax + movl %eax, %cr3 + # Load IDTR and GDTR for real mode + lidt go_real_idt + lgdt go_real_gdt + # Load DS & al + movl $0x0010, %eax + movl %eax, %ss + movl %eax, %ds + movl %eax, %es + movl %eax, %fs + movl %eax, %gs + # Load CS + call $0x0008, $(go_real - wakeup_start) + # Phony return code + call restore_registers + call restore_processor_state + ret + + .align 4 + .word 0 +go_real_idt: + .word 0x3ff + .long 0 + + .align 4 + .word 0 +go_real_gdt: + .word 3*8-1 + .long 0 + ALIGN # saved registers saved_gdt: .long 0,0 diff -ru -X dontdiff linux-2.6.7/drivers/video/aty/radeon_pm.c linux-2.6.7-p2120/drivers/video/aty/radeon_pm.c --- linux-2.6.7/drivers/video/aty/radeon_pm.c 2004-07-19 10:56:15.000000000 +0200 +++ linux-2.6.7-p2120/drivers/video/aty/radeon_pm.c 2004-07-19 10:56:34.000000000 +0200 @@ -897,6 +897,10 @@ if (pdev->dev.power_state == 0) return 0; + pci_restore_state (pdev, pdev->saved_config_space); + + acpi_vgapost (pdev->devfn); + acquire_console_sem(); /* Wakeup chip */ --=-=-=-- ------------------------------------------------------- This SF.Net email is sponsored by BEA Weblogic Workshop FREE Java Enterprise J2EE developer tools! Get your free copy of BEA WebLogic Workshop 8.1 today. http://ads.osdn.com/?ad_id=4721&alloc_id=10040&op=click