Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S261764AbVC1OQx (ORCPT ); Mon, 28 Mar 2005 09:16:53 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S261757AbVC1OQx (ORCPT ); Mon, 28 Mar 2005 09:16:53 -0500 Received: from unknown.xeex.net ([216.152.252.175]:34052 "EHLO mail.intworks.biz") by vger.kernel.org with ESMTP id S261764AbVC1OQP (ORCPT ); Mon, 28 Mar 2005 09:16:15 -0500 Date: Mon, 28 Mar 2005 06:15:58 -0800 From: jayalk@intworks.biz Message-Id: <200503281415.j2SEFwg4014119@intworks.biz> To: hpa@zytor.com Subject: [RFC 2.6.11.2 1/1] Add reboot fixup for gx1/cs5530a Cc: linux-kernel@vger.kernel.org, davej@codemonkey.org.uk Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 5310 Lines: 138 Hi Riley, Dave, Peter, i386 boot/workaround maintainers, I ran into a problem getting reboot working with 2.6.11 on an embedded board. The board has a Geode GX1 with a CS5530A companion. What I observe on reboot is the "Restarting system" printk, and then a cpu stall/hang. I think the problem arises because the keyboard controller is disabled by the BIOS, so the traditional mach_reboot()'s output to port 0x64 is ignored. Then the 386 triple fault issued after mach_reboot() results in a shutdown (because the hardware doesn't have to detect the triple fault and issue a reset). That then gives the end result of a stalled cpu/hang. I found that the CS5530A in question has a "issue system wide reset" bit. The reboot works cleanly if I write that bit rather than do mach_reboot(). So the following patch is my attempt to incorporate that change into 2.6.11 by adding a X86_REBOOTFIXUPS option. In order to keep reboot.c free of hw specific fixups, I put it in another file, reboot_fixups.c. I tried to make it a bit generic so that if there are other reboot related fixups for other chipsets/boards, there'd be a clean place to put it. Please let me know what you think. Thanks, Jaya Kumar --- Signed-off-by: Jaya Kumar diff -uprN -X dontdiff linux-2.6.11.2-vanilla/arch/i386/Kconfig linux-2.6.11.2/arch/i386/Kconfig --- linux-2.6.11.2-vanilla/arch/i386/Kconfig 2005-03-10 16:31:25.000000000 +0800 +++ linux-2.6.11.2/arch/i386/Kconfig 2005-03-28 21:30:15.000000000 +0800 @@ -645,6 +645,23 @@ config I8K Say Y if you intend to run this kernel on a Dell Inspiron 8000. Say N otherwise. +config X86_REBOOTFIXUPS + bool "Enable X86 Board Specific Fixups for Reboot" + depends on X86 + default n + ---help--- + This enables chipset and/or board specific fixups to be done + in order to get reboot to work correctly. This is only needed on + some combinations of hardware and BIOS. The symptom, for which + this config is intended, is when reboot ends with a stalled/hung + system. + + Currently, the only fixup is for the Geode GX1/CS5530A/TROM2.1. + combination. + + Say Y if you want to enable the fixup. + Say N otherwise. + config MICROCODE tristate "/dev/cpu/microcode - Intel IA32 CPU microcode support" ---help--- diff -uprN -X dontdiff linux-2.6.11.2-vanilla/arch/i386/kernel/Makefile linux-2.6.11.2/arch/i386/kernel/Makefile --- linux-2.6.11.2-vanilla/arch/i386/kernel/Makefile 2005-03-10 16:31:25.000000000 +0800 +++ linux-2.6.11.2/arch/i386/kernel/Makefile 2005-03-28 15:56:31.000000000 +0800 @@ -23,6 +23,7 @@ obj-$(CONFIG_X86_TRAMPOLINE) += trampoli obj-$(CONFIG_X86_MPPARSE) += mpparse.o obj-$(CONFIG_X86_LOCAL_APIC) += apic.o nmi.o obj-$(CONFIG_X86_IO_APIC) += io_apic.o +obj-$(CONFIG_X86_REBOOTFIXUPS) += reboot_fixups.o obj-$(CONFIG_X86_NUMAQ) += numaq.o obj-$(CONFIG_X86_SUMMIT_NUMA) += summit.o obj-$(CONFIG_KPROBES) += kprobes.o diff -uprN -X dontdiff linux-2.6.11.2-vanilla/arch/i386/kernel/reboot.c linux-2.6.11.2/arch/i386/kernel/reboot.c --- linux-2.6.11.2-vanilla/arch/i386/kernel/reboot.c 2005-03-10 16:31:25.000000000 +0800 +++ linux-2.6.11.2/arch/i386/kernel/reboot.c 2005-03-28 21:36:39.562079136 +0800 @@ -14,6 +14,10 @@ #include #include "mach_reboot.h" +#ifdef CONFIG_X86_REBOOTFIXUPS +extern void mach_reboot_fixups(void); +#endif + /* * Power off function, if any */ @@ -348,6 +352,9 @@ void machine_restart(char * __unused) /* rebooting needs to touch the page at absolute addr 0 */ *((unsigned short *)__va(0x472)) = reboot_mode; for (;;) { +#ifdef CONFIG_X86_REBOOTFIXUPS + mach_reboot_fixups(); +#endif mach_reboot(); /* That didn't work - force a triple fault.. */ __asm__ __volatile__("lidt %0": :"m" (no_idt)); diff -uprN -X dontdiff linux-2.6.11.2-vanilla/arch/i386/kernel/reboot_fixups.c linux-2.6.11.2/arch/i386/kernel/reboot_fixups.c --- linux-2.6.11.2-vanilla/arch/i386/kernel/reboot_fixups.c 1970-01-01 07:30:00.000000000 +0730 +++ linux-2.6.11.2/arch/i386/kernel/reboot_fixups.c 2005-03-28 21:38:30.893154240 +0800 @@ -0,0 +1,40 @@ +#include +#include + +void cs5530a_warm_reset(struct pci_dev *dev) +{ + /* writing 1 to the reset control register, 0x44 causes the + cs5530a to perform a system warm reset */ + pci_write_config_byte(dev, 0x44, 0x1); + udelay(50); /* shouldn't get here but be safe and spin-a-while */ + return; +} + +struct device_fixup { + unsigned int vendor; + unsigned int device; + void (*reboot_fixup)(struct pci_dev *); +}; + +struct device_fixup fixups_table[] = { + { PCI_VENDOR_ID_CYRIX, PCI_DEVICE_ID_CYRIX_5530_LEGACY, cs5530a_warm_reset }, +}; + +void mach_reboot_fixups(void) +{ + struct device_fixup *cur; + struct pci_dev *dev; + int i; + + for (i=0; i < (sizeof(fixups_table)/sizeof(fixups_table[0])); i++) { + cur = fixups_table + i; + dev = pci_find_device(cur->vendor, cur->device, 0); + if (!dev) + continue; + + cur->reboot_fixup(dev); + } + + printk(KERN_WARNING "No reboot fixup found for your hardware\n"); +} + - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/