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-rw-r--r--Documentation/x86_64/boot-options.txt4
-rw-r--r--arch/x86_64/kernel/early-quirks.c5
-rw-r--r--arch/x86_64/kernel/io_apic.c124
3 files changed, 82 insertions, 51 deletions
diff --git a/Documentation/x86_64/boot-options.txt b/Documentation/x86_64/boot-options.txt
index dbdcaf68e3ea..5c86ed6f0448 100644
--- a/Documentation/x86_64/boot-options.txt
+++ b/Documentation/x86_64/boot-options.txt
@@ -52,6 +52,10 @@ APICs
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 829698f6d049..49802f1bee94 100644
--- a/arch/x86_64/kernel/early-quirks.c
+++ b/arch/x86_64/kernel/early-quirks.c
@@ -69,6 +69,11 @@ static void nvidia_bugs(void)
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");
+ }
}
static void intel_bugs(void)
diff --git a/arch/x86_64/kernel/io_apic.c b/arch/x86_64/kernel/io_apic.c
index 2a1dcd5f69c2..d7bad90a5ad8 100644
--- a/arch/x86_64/kernel/io_apic.c
+++ b/arch/x86_64/kernel/io_apic.c
@@ -55,6 +55,10 @@ int sis_apic_bug; /* not actually supported, dummy for compile */
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 };
@@ -350,6 +354,29 @@ static int __init disable_ioapic_setup(char *str)
}
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+/* Actually the next is obsolete, but keep it for paranoid reasons -AK */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.
*/
@@ -1568,33 +1595,10 @@ static inline void unlock_ExtINT_logic(void)
* 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 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)
+static inline void check_timer(void)
{
int apic1, pin1, apic2, pin2;
int vector;
@@ -1615,43 +1619,61 @@ static void check_timer(void)
*/
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;
- /* Do this first, otherwise we get double interrupts on ATI boards */
- if ((pin1 != -1) && try_apic_pin(apic1, pin1,"with 8259 IRQ0 disabled"))
- return;
+ apic_printk(APIC_VERBOSE,KERN_INFO "..TIMER: vector=0x%02X apic1=%d pin1=%d apic2=%d pin2=%d\n",
+ vector, apic1, pin1, apic2, pin2);
- /* 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);
-
- /* 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;
+ 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");
+ }
- /* Then try pure 8259A routing on the 8259 as reported by BIOS*/
- enable_8259A_irq(0);
+ apic_printk(APIC_VERBOSE,KERN_INFO "...trying to set up timer (IRQ0) "
+ "through the 8259A ... ");
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 (try_apic_pin(apic2,pin2,"8259A broadcast ExtINT from BIOS"))
+ if (timer_irq_works()) {
+ apic_printk(APIC_VERBOSE," works.\n");
+ nmi_watchdog_default();
+ if (nmi_watchdog == NMI_IO_APIC) {
+ setup_nmi();
+ }
return;
+ }
+ /*
+ * Cleanup, just in case ...
+ */
+ clear_IO_APIC_pin(apic2, pin2);
}
-
- /* Tried all possibilities to go through the IO-APIC. Now come the
- really cheesy fallbacks. */
+ apic_printk(APIC_VERBOSE," failed.\n");
if (nmi_watchdog == NMI_IO_APIC) {
printk(KERN_WARNING "timer doesn't work through the IO-APIC - disabling NMI Watchdog!\n");