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-rw-r--r--src/arch/x86/ioapic.c153
1 files changed, 153 insertions, 0 deletions
diff --git a/src/arch/x86/ioapic.c b/src/arch/x86/ioapic.c
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+++ b/src/arch/x86/ioapic.c
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+/*
+ * This file is part of the coreboot project.
+ *
+ * Copyright (C) 2010 coresystems GmbH
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 of the License.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc.
+ */
+
+#include <arch/io.h>
+#include <arch/ioapic.h>
+#include <console/console.h>
+#include <cpu/x86/lapic.h>
+
+u32 io_apic_read(void *ioapic_base, u32 reg)
+{
+ write32(ioapic_base, reg);
+ return read32(ioapic_base + 0x10);
+}
+
+void io_apic_write(void *ioapic_base, u32 reg, u32 value)
+{
+ write32(ioapic_base, reg);
+ write32(ioapic_base + 0x10, value);
+}
+
+static int ioapic_interrupt_count(void *ioapic_base)
+{
+ /* Read the available number of interrupts. */
+ int ioapic_interrupts = (io_apic_read(ioapic_base, 0x01) >> 16) & 0xff;
+ if (ioapic_interrupts == 0xff)
+ ioapic_interrupts = 23;
+ ioapic_interrupts += 1; /* Bits 23-16 specify the maximum redirection
+ entry, which is the number of interrupts
+ minus 1. */
+ printk(BIOS_DEBUG, "IOAPIC: %d interrupts\n", ioapic_interrupts);
+
+ return ioapic_interrupts;
+}
+
+void clear_ioapic(void *ioapic_base)
+{
+ u32 low, high;
+ u32 i, ioapic_interrupts;
+
+ printk(BIOS_DEBUG, "IOAPIC: Clearing IOAPIC at %p\n", ioapic_base);
+
+ ioapic_interrupts = ioapic_interrupt_count(ioapic_base);
+
+ low = DISABLED;
+ high = NONE;
+
+ for (i = 0; i < ioapic_interrupts; i++) {
+ io_apic_write(ioapic_base, i * 2 + 0x10, low);
+ io_apic_write(ioapic_base, i * 2 + 0x11, high);
+
+ printk(BIOS_SPEW, "IOAPIC: reg 0x%08x value 0x%08x 0x%08x\n",
+ i, high, low);
+ }
+
+ if (io_apic_read(ioapic_base, 0x10) == 0xffffffff) {
+ printk(BIOS_WARNING, "IOAPIC not responding.\n");
+ return;
+ }
+}
+
+void set_ioapic_id(void *ioapic_base, u8 ioapic_id)
+{
+ u32 bsp_lapicid = lapicid();
+ int i;
+
+ printk(BIOS_DEBUG, "IOAPIC: Initializing IOAPIC at 0x%p\n",
+ ioapic_base);
+ printk(BIOS_DEBUG, "IOAPIC: Bootstrap Processor Local APIC = 0x%02x\n",
+ bsp_lapicid);
+
+ if (ioapic_id) {
+ printk(BIOS_DEBUG, "IOAPIC: ID = 0x%02x\n", ioapic_id);
+ /* Set IOAPIC ID if it has been specified. */
+ io_apic_write(ioapic_base, 0x00,
+ (io_apic_read(ioapic_base, 0x00) & 0xf0ffffff) |
+ (ioapic_id << 24));
+ }
+
+ printk(BIOS_SPEW, "IOAPIC: Dumping registers\n");
+ for (i = 0; i < 3; i++)
+ printk(BIOS_SPEW, " reg 0x%04x: 0x%08x\n", i,
+ io_apic_read(ioapic_base, i));
+
+}
+
+static void load_vectors(void *ioapic_base)
+{
+ u32 bsp_lapicid = lapicid();
+ u32 low, high;
+ u32 i, ioapic_interrupts;
+
+ ioapic_interrupts = ioapic_interrupt_count(ioapic_base);
+
+#if CONFIG_IOAPIC_INTERRUPTS_ON_FSB
+ /*
+ * For the Pentium 4 and above APICs deliver their interrupts
+ * on the front side bus, enable that.
+ */
+ printk(BIOS_DEBUG, "IOAPIC: Enabling interrupts on FSB\n");
+ io_apic_write(ioapic_base, 0x03,
+ io_apic_read(ioapic_base, 0x03) | (1 << 0));
+#endif
+#if CONFIG_IOAPIC_INTERRUPTS_ON_APIC_SERIAL_BUS
+ printk(BIOS_DEBUG, "IOAPIC: Enabling interrupts on APIC serial bus\n");
+ io_apic_write(ioapic_base, 0x03, 0);
+#endif
+
+ /* Enable Virtual Wire Mode. */
+ low = ENABLED | TRIGGER_EDGE | POLARITY_HIGH | PHYSICAL_DEST | ExtINT;
+ high = bsp_lapicid << (56 - 32);
+
+ io_apic_write(ioapic_base, 0x10, low);
+ io_apic_write(ioapic_base, 0x11, high);
+
+ if (io_apic_read(ioapic_base, 0x10) == 0xffffffff) {
+ printk(BIOS_WARNING, "IOAPIC not responding.\n");
+ return;
+ }
+
+ printk(BIOS_SPEW, "IOAPIC: reg 0x%08x value 0x%08x 0x%08x\n",
+ 0, high, low);
+ low = DISABLED;
+ high = NONE;
+ for (i = 1; i < ioapic_interrupts; i++) {
+ io_apic_write(ioapic_base, i * 2 + 0x10, low);
+ io_apic_write(ioapic_base, i * 2 + 0x11, high);
+
+ printk(BIOS_SPEW, "IOAPIC: reg 0x%08x value 0x%08x 0x%08x\n",
+ i, high, low);
+ }
+}
+
+void setup_ioapic(void *ioapic_base, u8 ioapic_id)
+{
+ set_ioapic_id(ioapic_base, ioapic_id);
+ load_vectors(ioapic_base);
+}
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