drivers/generic/ioapic: Drop poor implementation

This disables MP table generation for the affected boards
since interrupt routing entries would now be completely missing.

The mechanism itself is flawed and redundant. The mapping
of integrated PCI devices' INTx pins to IOAPIC pins is
dependent of configuration registers and needs not appear
in the devicetree.cb files at all.

The write_smp_table implementation would skip writing
any entry delivering to destination IOAPIC ID 0. This
does not follow MP table specification.

There were duplicate calls to register_new_ioapic_gsi0(),
with another present under southbridge LPC device.

Change-Id: I383d55ba2bc0800423617215e0bfdfad5136e9ac
Signed-off-by: Kyösti Mälkki <kyosti.malkki@gmail.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/69488
Reviewed-by: Arthur Heymans <arthur@aheymans.xyz>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Angel Pons <th3fanbus@gmail.com>

1 files changed, 1 insertions, 118 deletions

diff --git a/src/arch/x86/mpspec.c b/src/arch/x86/mpspec.c
index d94308ee18..15b64b3086 100644
--- a/src/arch/x86/mpspec.c
+++ b/src/arch/x86/mpspec.c
@@ -9,7 +9,6 @@
 #include <device/device.h>
 #include <device/path.h>
 #include <device/pci_ids.h>
-#include <drivers/generic/ioapic/chip.h>
 #include <stdint.h>
 #include <string.h>
 
@@ -509,34 +508,11 @@ void *mptable_finalize(struct mp_config_table *mc)
 	return smp_next_mpe_entry(mc);
 }
 
-static const struct device *find_next_ioapic(unsigned int last_ioapic_id)
-{
-	const struct device *dev;
-	const struct device *result = NULL;
-	unsigned int ioapic_id = MAX_APICS;
-
-	for (dev = all_devices; dev; dev = dev->next) {
-		if (dev->path.type == DEVICE_PATH_IOAPIC &&
-		    dev->path.ioapic.ioapic_id > last_ioapic_id &&
-		    dev->path.ioapic.ioapic_id <= ioapic_id) {
-			result = dev;
-		}
-	}
-	return result;
-}
-
 unsigned long __weak write_smp_table(unsigned long addr)
 {
-	struct drivers_generic_ioapic_config *ioapic_config;
 	struct mp_config_table *mc;
-	int isa_bus, pin, parentpin;
-	const struct device *dev;
-	const struct device *parent;
-	const struct device *oldparent;
+	int isa_bus;
 	void *tmp, *v;
-	int isaioapic = -1, have_fixed_entries;
-	const struct pci_irq_info *pci_irq_info;
-	unsigned int ioapic_id = 0;
 
 	v = smp_write_floating_table(addr, 0);
 	mc = (void *)(((char *)v) + SMP_FLOATING_TABLE_LEN);
@@ -547,99 +523,6 @@ unsigned long __weak write_smp_table(unsigned long addr)
 
 	mptable_write_buses(mc, NULL, &isa_bus);
 
-	while ((dev = find_next_ioapic(ioapic_id))) {
-		ioapic_config = dev->chip_info;
-		if (!ioapic_config) {
-			printk(BIOS_ERR, "%s has no config, ignoring\n",
-				dev_path(dev));
-			ioapic_id++;
-			continue;
-		}
-
-		ioapic_id = dev->path.ioapic.ioapic_id;
-		smp_write_ioapic(mc, ioapic_id,
-				     ioapic_config->version,
-				     ioapic_config->base);
-
-		if (ioapic_config->have_isa_interrupts) {
-			if (isaioapic >= 0)
-				printk(BIOS_ERR,
-					"More than one IOAPIC with ISA interrupts?\n");
-			else
-				isaioapic = dev->path.ioapic.ioapic_id;
-		}
-	}
-
-	if (isaioapic >= 0) {
-		/* Legacy Interrupts */
-		printk(BIOS_DEBUG, "Writing ISA IRQs\n");
-		mptable_add_isa_interrupts(mc, isa_bus, isaioapic, 0);
-	}
-
-	for (dev = all_devices; dev; dev = dev->next) {
-
-		if (!is_enabled_pci(dev))
-			continue;
-
-		have_fixed_entries = 0;
-		for (pin = 0; pin < 4; pin++) {
-			if (dev->pci_irq_info[pin].ioapic_dst_id) {
-				printk(BIOS_DEBUG,
-					"fixed IRQ entry for: %s: INT%c# -> IOAPIC %d PIN %d\n",
-						dev_path(dev),
-				       pin + 'A',
-				       dev->pci_irq_info[pin].ioapic_dst_id,
-				       dev->pci_irq_info[pin].ioapic_irq_pin);
-				smp_write_intsrc(mc, mp_INT,
-					 dev->pci_irq_info[pin].ioapic_flags,
-					 dev->bus->secondary,
-					 ((dev->path.pci.devfn & 0xf8) >> 1)
-						| pin,
-					 dev->pci_irq_info[pin].ioapic_dst_id,
-					 dev->pci_irq_info[pin].ioapic_irq_pin);
-				have_fixed_entries = 1;
-			}
-		}
-
-		if (!have_fixed_entries) {
-			pin = (dev->path.pci.devfn & 7) % 4;
-			oldparent = parent = dev;
-			while ((parent = parent->bus->dev)) {
-				parentpin = (oldparent->path.pci.devfn >> 3)
-					+ (oldparent->path.pci.devfn & 7);
-				parentpin += dev->path.pci.devfn & 7;
-				parentpin += dev->path.pci.devfn >> 3;
-				parentpin %= 4;
-
-				pci_irq_info = &parent->pci_irq_info[parentpin];
-				if (pci_irq_info->ioapic_dst_id) {
-					printk(BIOS_DEBUG,
-					       "automatic IRQ entry for %s: INT%c# -> IOAPIC %d PIN %d\n",
-					       dev_path(dev), pin + 'A',
-					       pci_irq_info->ioapic_dst_id,
-					       pci_irq_info->ioapic_irq_pin);
-					smp_write_intsrc(mc, mp_INT,
-						 pci_irq_info->ioapic_flags,
-						 dev->bus->secondary,
-						 ((dev->path.pci.devfn & 0xf8)
-							>> 1) | pin,
-						 pci_irq_info->ioapic_dst_id,
-						 pci_irq_info->ioapic_irq_pin);
-
-					break;
-				}
-
-				if (parent->path.type == DEVICE_PATH_DOMAIN) {
-					printk(BIOS_WARNING,
-						"no IRQ found for %s\n",
-						dev_path(dev));
-					break;
-				}
-				oldparent = parent;
-			}
-		}
-	}
-
 	mptable_lintsrc(mc, isa_bus);
 	tmp = mptable_finalize(mc);
 	printk(BIOS_INFO, "MPTABLE len: %d\n", (unsigned int)((uintptr_t)tmp -