[PATCH] Insert Local and IO APIC(s) into resource map

From: Aaron Durbin
Date: Thu Sep 28 2006 - 14:21:32 EST


This patch inserts the Local APIC and IO APIC(s) into the resource tree. It
allows the APIC resources to be visible within /proc/iomem. The patch
also takes into account IO APIC(s) mapped in the PCI space by deferring
the insertion until after PCI has allocated its necessary resources.

Signed-off-by: Aaron Durbin <adurbin@xxxxxxxxxx>

---

The previous patch addressing thsi functionality should be dropped and replaced
with this newer particular patch.

The patch is against 2.6.18.

arch/x86_64/kernel/apic.c | 78 +++++++++++++++++++++++++++++++++++++++++++++
1 files changed, 78 insertions(+), 0 deletions(-)

diff --git a/arch/x86_64/kernel/apic.c b/arch/x86_64/kernel/apic.c
index 2b8cef0..6880d83 100644
--- a/arch/x86_64/kernel/apic.c
+++ b/arch/x86_64/kernel/apic.c
@@ -25,6 +25,7 @@ #include <linux/mc146818rtc.h>
#include <linux/kernel_stat.h>
#include <linux/sysdev.h>
#include <linux/module.h>
+#include <linux/ioport.h>

#include <asm/atomic.h>
#include <asm/smp.h>
@@ -43,6 +44,12 @@ int apic_calibrate_pmtmr __initdata;

int disable_apic_timer __initdata;

+static struct resource *ioapic_resources;
+static struct resource lapic_resource = {
+ .name = "Local APIC",
+ .flags = IORESOURCE_MEM | IORESOURCE_BUSY,
+};
+
/*
* cpu_mask that denotes the CPUs that needs timer interrupt coming in as
* IPIs in place of local APIC timers
@@ -638,6 +645,64 @@ static int __init detect_init_APIC (void
return 0;
}

+#ifdef CONFIG_X86_IO_APIC
+static struct resource * __init ioapic_setup_resources(void)
+{
+#define IOAPIC_RESOURCE_NAME_SIZE 11
+ unsigned long n;
+ struct resource *res;
+ char *mem;
+ int i;
+
+ if (nr_ioapics <= 0)
+ return NULL;
+
+ n = IOAPIC_RESOURCE_NAME_SIZE + sizeof(struct resource);
+ n *= nr_ioapics;
+
+ mem = alloc_bootmem(n);
+ res = (void *)mem;
+
+ if (mem != NULL) {
+ memset(mem, 0, n);
+ mem += sizeof(struct resource) * nr_ioapics;
+
+ for (i = 0; i < nr_ioapics; i++) {
+ res[i].name = mem;
+ res[i].flags = IORESOURCE_MEM | IORESOURCE_BUSY;
+ sprintf(mem, "IOAPIC %u", i);
+ mem += IOAPIC_RESOURCE_NAME_SIZE;
+ }
+ }
+
+ ioapic_resources = res;
+
+ return res;
+}
+
+static int __init ioapic_insert_resources(void)
+{
+ int i;
+ struct resource *r = ioapic_resources;
+
+ if (!r) {
+ printk("IO APIC resources could be not be allocated.\n");
+ return -1;
+ }
+
+ for (i = 0; i < nr_ioapics; i++) {
+ insert_resource(&iomem_resource, r);
+ r++;
+ }
+
+ return 0;
+}
+
+/* Insert the IO APIC resources after PCI initialization has occured to handle
+ * IO APICS that are mapped in on a BAR in PCI space. */
+late_initcall(ioapic_insert_resources);
+#endif
+
void __init init_apic_mappings(void)
{
unsigned long apic_phys;
@@ -656,6 +721,11 @@ void __init init_apic_mappings(void)
set_fixmap_nocache(FIX_APIC_BASE, apic_phys);
apic_printk(APIC_VERBOSE,"mapped APIC to %16lx (%16lx)\n", APIC_BASE, apic_phys);

+ /* Put local APIC into the resource map. */
+ lapic_resource.start = apic_phys;
+ lapic_resource.end = lapic_resource.start + PAGE_SIZE - 1;
+ insert_resource(&iomem_resource, &lapic_resource);
+
/*
* Fetch the APIC ID of the BSP in case we have a
* default configuration (or the MP table is broken).
@@ -666,7 +736,9 @@ #ifdef CONFIG_X86_IO_APIC
{
unsigned long ioapic_phys, idx = FIX_IO_APIC_BASE_0;
int i;
+ struct resource *ioapic_res;

+ ioapic_res = ioapic_setup_resources();
for (i = 0; i < nr_ioapics; i++) {
if (smp_found_config) {
ioapic_phys = mp_ioapics[i].mpc_apicaddr;
@@ -678,6 +750,12 @@ #ifdef CONFIG_X86_IO_APIC
apic_printk(APIC_VERBOSE,"mapped IOAPIC to %016lx (%016lx)\n",
__fix_to_virt(idx), ioapic_phys);
idx++;
+
+ if (ioapic_res != NULL) {
+ ioapic_res->start = ioapic_phys;
+ ioapic_res->end = ioapic_phys + (4 * 1024) - 1;
+ ioapic_res++;
+ }
}
}
#endif
--
1.4.2.1.g4daf

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