Add IOAPIC support for Intel 82371EB and fixup SMP on ASUS P2B-D.
- Add enable_intel_82093aa_ioapic() which enables IOAPIC usage in the
Intel 82371EB southbridge (sets the proper chip-select) and sets an
IOAPIC ID.
- We only call enable_intel_82093aa_ioapic() if a board does "select IOAPIC"
as on 82371EB-based boards the IOAPIC is an external chip (not integrated
in the southbridge) and it's only populated on multi-CPU boards.
That is, we cannot unconditionally enable it, only on SMP-capable boards.
- Due to the reason explained above, remove "select IOAPIC" from
src/southbridge/intel/i82371eb/Kconfig, and add it to
src/mainboard/asus/p2b-d/Kconfig.
- Also set CONFIG_MAX_PHYSICAL_CPUS to 2 on ASUS P2B-D. There are two
CPU sockets (Slot 1) and each CPU can only have one core, multi-core CPUs
didn't exist in that era (CONFIG_MAX_CPUS was set to 2 already).
- Drop useless/duplicated enable_lapic() call from ASUS P2B-D's romstage.c,
that function is always called if either CONFIG_SMP and/or CONFIG_IOAPIC
are set.
- Rework ASUS P2B-D mptable.c to fix a number of things:
- Convert it to use mptable_write_buses() as all mptable.c files should do.
- Fix incorrect IOAPICID (it's 0x11 for the external 82093AA IOAPIC).
- Fix a bunch of hardcoded bus IDs, remove incorrect entries, etc.
This is build-tested on ASUS P2B-D, and also boot-tested successfully there.
On Linux I now get two entries in /proc/cpuinfo (where only one appeared
before this patch), i.e. both populated CPUs are found.
Signed-off-by: Uwe Hermann <uwe@hermann-uwe.de>
Acked-by: Uwe Hermann <uwe@hermann-uwe.de>
git-svn-id: svn://svn.coreboot.org/coreboot/trunk@5998 2b7e53f0-3cfb-0310-b3e9-8179ed1497e1
diff --git a/src/southbridge/intel/i82371eb/i82371eb_isa.c b/src/southbridge/intel/i82371eb/i82371eb_isa.c
index 0cc46a6..24d3813 100644
--- a/src/southbridge/intel/i82371eb/i82371eb_isa.c
+++ b/src/southbridge/intel/i82371eb/i82371eb_isa.c
@@ -28,6 +28,35 @@
#include <arch/ioapic.h>
#include "i82371eb.h"
+static void enable_intel_82093aa_ioapic(void)
+{
+ u16 reg16;
+ u32 reg32;
+ u8 ioapic_id = 2;
+ volatile u32 *ioapic_index = (volatile u32 *)(IO_APIC_ADDR);
+ volatile u32 *ioapic_data = (volatile u32 *)(IO_APIC_ADDR + 0x10);
+ device_t dev;
+
+ dev = dev_find_device(PCI_VENDOR_ID_INTEL,
+ PCI_DEVICE_ID_INTEL_82371AB_ISA, 0);
+
+ /* Enable IOAPIC. */
+ reg16 = pci_read_config16(dev, XBCS);
+ reg16 |= (1 << 8); /* APIC Chip Select */
+ pci_write_config16(dev, XBCS, reg16);
+
+ /* Set the IOAPIC ID. */
+ *ioapic_index = 0;
+ *ioapic_data = ioapic_id << 24;
+
+ /* Read back and verify the IOAPIC ID. */
+ *ioapic_index = 0;
+ reg32 = (*ioapic_data >> 24) & 0x0f;
+ printk(BIOS_DEBUG, "IOAPIC ID = %x\n", reg32);
+ if (reg32 != ioapic_id)
+ die("IOAPIC error!\n");
+}
+
static void isa_init(struct device *dev)
{
u32 reg32;
@@ -45,6 +74,18 @@
/* Initialize ISA DMA. */
isa_dma_init();
+
+#if CONFIG_IOAPIC
+ /*
+ * Unlike most other southbridges the 82371EB doesn't have a built-in
+ * IOAPIC. Instead, 82371EB-based boards that support multiple CPUs
+ * have a discrete IOAPIC (Intel 82093AA) soldered onto the board.
+ *
+ * Thus, we can/must only enable the IOAPIC if it actually exists,
+ * i.e. the respective mainboard does "select IOAPIC".
+ */
+ enable_intel_82093aa_ioapic();
+#endif
}
static void sb_read_resources(struct device *dev)