[PATCH] x86-64: Try multiple timer variants in check_timer
Instead of adding all kinds of more quirks try various timer
routing variants in check_timer.
In particular this tries to handle quirks from:
- Nvidia NF2-4 reference BIOS: wrong timer override
- Asus: Wrong timer override but no HPET table
- ATI: require timer disabled in 8259
- Some boards: require timer enabled in 8259
We just try many of the the known variants in the hopefully right order
in check_timer.
Trying pin 0/2 on Nvidia suggested by Tim Hockin.
TBD Experimental. Needs a lot of testing
Signed-off-by: Andi Kleen <ak@suse.de>
diff --git a/Documentation/x86_64/boot-options.txt b/Documentation/x86_64/boot-options.txt
index f3c57f4..ab9b1c0 100644
--- a/Documentation/x86_64/boot-options.txt
+++ b/Documentation/x86_64/boot-options.txt
@@ -52,10 +52,6 @@
apicmaintimer. Useful when your PIT timer is totally
broken.
- disable_8254_timer / enable_8254_timer
- Enable interrupt 0 timer routing over the 8254 in addition to over
- the IO-APIC. The kernel tries to set a sensible default.
-
Early Console
syntax: earlyprintk=vga
diff --git a/arch/x86_64/kernel/early-quirks.c b/arch/x86_64/kernel/early-quirks.c
index 68273bf..fb0c6da 100644
--- a/arch/x86_64/kernel/early-quirks.c
+++ b/arch/x86_64/kernel/early-quirks.c
@@ -69,11 +69,6 @@
static void ati_bugs(void)
{
- if (timer_over_8254 == 1) {
- timer_over_8254 = 0;
- printk(KERN_INFO
- "ATI board detected. Disabling timer routing over 8254.\n");
- }
}
struct chipset {
diff --git a/arch/x86_64/kernel/io_apic.c b/arch/x86_64/kernel/io_apic.c
index f71461b..88fcc4e 100644
--- a/arch/x86_64/kernel/io_apic.c
+++ b/arch/x86_64/kernel/io_apic.c
@@ -55,10 +55,6 @@
static int no_timer_check;
-static int disable_timer_pin_1 __initdata;
-
-int timer_over_8254 __initdata = 1;
-
/* Where if anywhere is the i8259 connect in external int mode */
static struct { int pin, apic; } ioapic_i8259 = { -1, -1 };
@@ -348,29 +344,6 @@
}
early_param("noapic", disable_ioapic_setup);
-/* Actually the next is obsolete, but keep it for paranoid reasons -AK */
-static int __init disable_timer_pin_setup(char *arg)
-{
- disable_timer_pin_1 = 1;
- return 1;
-}
-__setup("disable_timer_pin_1", disable_timer_pin_setup);
-
-static int __init setup_disable_8254_timer(char *s)
-{
- timer_over_8254 = -1;
- return 1;
-}
-static int __init setup_enable_8254_timer(char *s)
-{
- timer_over_8254 = 2;
- return 1;
-}
-
-__setup("disable_8254_timer", setup_disable_8254_timer);
-__setup("enable_8254_timer", setup_enable_8254_timer);
-
-
/*
* Find the IRQ entry number of a certain pin.
*/
@@ -1579,10 +1552,33 @@
* a wide range of boards and BIOS bugs. Fortunately only the timer IRQ
* is so screwy. Thanks to Brian Perkins for testing/hacking this beast
* fanatically on his truly buggy board.
- *
- * FIXME: really need to revamp this for modern platforms only.
*/
-static inline void check_timer(void)
+
+static int try_apic_pin(int apic, int pin, char *msg)
+{
+ apic_printk(APIC_VERBOSE, KERN_INFO
+ "..TIMER: trying IO-APIC=%d PIN=%d %s",
+ apic, pin, msg);
+
+ /*
+ * Ok, does IRQ0 through the IOAPIC work?
+ */
+ if (!no_timer_check && timer_irq_works()) {
+ nmi_watchdog_default();
+ if (nmi_watchdog == NMI_IO_APIC) {
+ disable_8259A_irq(0);
+ setup_nmi();
+ enable_8259A_irq(0);
+ }
+ return 1;
+ }
+ clear_IO_APIC_pin(apic, pin);
+ apic_printk(APIC_QUIET, KERN_ERR " .. failed\n");
+ return 0;
+}
+
+/* The function from hell */
+static void check_timer(void)
{
int apic1, pin1, apic2, pin2;
int vector;
@@ -1603,61 +1599,43 @@
*/
apic_write(APIC_LVT0, APIC_LVT_MASKED | APIC_DM_EXTINT);
init_8259A(1);
- if (timer_over_8254 > 0)
- enable_8259A_irq(0);
pin1 = find_isa_irq_pin(0, mp_INT);
apic1 = find_isa_irq_apic(0, mp_INT);
pin2 = ioapic_i8259.pin;
apic2 = ioapic_i8259.apic;
- apic_printk(APIC_VERBOSE,KERN_INFO "..TIMER: vector=0x%02X apic1=%d pin1=%d apic2=%d pin2=%d\n",
- vector, apic1, pin1, apic2, pin2);
+ /* Do this first, otherwise we get double interrupts on ATI boards */
+ if ((pin1 != -1) && try_apic_pin(apic1, pin1,"with 8259 IRQ0 disabled"))
+ return;
- if (pin1 != -1) {
- /*
- * Ok, does IRQ0 through the IOAPIC work?
- */
- unmask_IO_APIC_irq(0);
- if (!no_timer_check && timer_irq_works()) {
- nmi_watchdog_default();
- if (nmi_watchdog == NMI_IO_APIC) {
- disable_8259A_irq(0);
- setup_nmi();
- enable_8259A_irq(0);
- }
- if (disable_timer_pin_1 > 0)
- clear_IO_APIC_pin(0, pin1);
- return;
- }
- clear_IO_APIC_pin(apic1, pin1);
- apic_printk(APIC_QUIET,KERN_ERR "..MP-BIOS bug: 8254 timer not "
- "connected to IO-APIC\n");
- }
+ /* Now try again with IRQ0 8259A enabled.
+ Assumes timer is on IO-APIC 0 ?!? */
+ enable_8259A_irq(0);
+ unmask_IO_APIC_irq(0);
+ if (try_apic_pin(apic1, pin1, "with 8259 IRQ0 enabled"))
+ return;
+ disable_8259A_irq(0);
- apic_printk(APIC_VERBOSE,KERN_INFO "...trying to set up timer (IRQ0) "
- "through the 8259A ... ");
+ /* Always try pin0 and pin2 on APIC 0 to handle buggy timer overrides
+ on Nvidia boards */
+ if (!(apic1 == 0 && pin1 == 0) &&
+ try_apic_pin(0, 0, "fallback with 8259 IRQ0 disabled"))
+ return;
+ if (!(apic1 == 0 && pin1 == 2) &&
+ try_apic_pin(0, 2, "fallback with 8259 IRQ0 disabled"))
+ return;
+
+ /* Then try pure 8259A routing on the 8259 as reported by BIOS*/
+ enable_8259A_irq(0);
if (pin2 != -1) {
- apic_printk(APIC_VERBOSE,"\n..... (found apic %d pin %d) ...",
- apic2, pin2);
- /*
- * legacy devices should be connected to IO APIC #0
- */
setup_ExtINT_IRQ0_pin(apic2, pin2, vector);
- if (timer_irq_works()) {
- apic_printk(APIC_VERBOSE," works.\n");
- nmi_watchdog_default();
- if (nmi_watchdog == NMI_IO_APIC) {
- setup_nmi();
- }
+ if (try_apic_pin(apic2,pin2,"8259A broadcast ExtINT from BIOS"))
return;
- }
- /*
- * Cleanup, just in case ...
- */
- clear_IO_APIC_pin(apic2, pin2);
}
- apic_printk(APIC_VERBOSE," failed.\n");
+
+ /* Tried all possibilities to go through the IO-APIC. Now come the
+ really cheesy fallbacks. */
if (nmi_watchdog == NMI_IO_APIC) {
printk(KERN_WARNING "timer doesn't work through the IO-APIC - disabling NMI Watchdog!\n");