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[v3,16/19] hw/intc/ioapic: Remove IOAPICCommonState::version field

Message ID 20250502185652.67370-17-philmd@linaro.org
State New
Headers show
Series hw/i386/pc: Remove deprecated 2.6 and 2.7 PC machines | expand

Commit Message

Philippe Mathieu-Daudé May 2, 2025, 6:56 p.m. UTC
The IOAPICCommonState::version integer was only set
in the hw_compat_2_7[] array, via the 'version=0x11'
property. We removed all machines using that array,
lets remove that property, simplify by only using the
default version (defined as IOAPIC_VER_DEF).

For the record, this field was introduced in commit
20fd4b7b6d9 ("x86: ioapic: add support for explicit EOI"):

 >   Some old Linux kernels (upstream before v4.0), or any released RHEL
 >   kernels has problem in sending APIC EOI when IR is enabled.
 >   Meanwhile, many of them only support explicit EOI for IOAPIC, which
 >   is only introduced in IOAPIC version 0x20. This patch provide a way
 >   to boost QEMU IOAPIC to version 0x20, in order for QEMU to correctly
 >   receive EOI messages.
 >
 >   Without boosting IOAPIC version to 0x20, kernels before commit
 >   d32932d ("x86/irq: Convert IOAPIC to use hierarchical irqdomain
 >   interfaces") will have trouble enabling both IR and level-triggered
 >   interrupt devices (like e1000).
 >
 >   To upgrade IOAPIC to version 0x20, we need to specify:
 >
 >     -global ioapic.version=0x20
 >
 >   To be compatible with old systems, 0x11 will still be the default
 >   IOAPIC version. Here 0x11 and 0x20 are the only versions to be
 >   supported.
 >
 >   One thing to mention: this patch only applies to emulated IOAPIC. It
 >   does not affect kernel IOAPIC behavior.

Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Mark Cave-Ayland <mark.caveayland@nutanix.com>
---
 hw/intc/ioapic_internal.h |  3 +--
 hw/intc/ioapic.c          | 18 ++----------------
 hw/intc/ioapic_common.c   |  2 +-
 3 files changed, 4 insertions(+), 19 deletions(-)
diff mbox series

Patch

diff --git a/hw/intc/ioapic_internal.h b/hw/intc/ioapic_internal.h
index 51205767f44..330ce195222 100644
--- a/hw/intc/ioapic_internal.h
+++ b/hw/intc/ioapic_internal.h
@@ -82,7 +82,7 @@ 
 #define IOAPIC_ID_MASK                  0xf
 
 #define IOAPIC_VER_ENTRIES_SHIFT        16
-
+#define IOAPIC_VER_DEF                  0x20
 
 #define TYPE_IOAPIC_COMMON "ioapic-common"
 OBJECT_DECLARE_TYPE(IOAPICCommonState, IOAPICCommonClass, IOAPIC_COMMON)
@@ -104,7 +104,6 @@  struct IOAPICCommonState {
     uint32_t irr;
     uint64_t ioredtbl[IOAPIC_NUM_PINS];
     Notifier machine_done;
-    uint8_t version;
     uint64_t irq_count[IOAPIC_NUM_PINS];
     int irq_level[IOAPIC_NUM_PINS];
     int irq_eoi[IOAPIC_NUM_PINS];
diff --git a/hw/intc/ioapic.c b/hw/intc/ioapic.c
index 133bef852d1..5cc97767d9d 100644
--- a/hw/intc/ioapic.c
+++ b/hw/intc/ioapic.c
@@ -315,7 +315,7 @@  ioapic_mem_read(void *opaque, hwaddr addr, unsigned int size)
             val = s->id << IOAPIC_ID_SHIFT;
             break;
         case IOAPIC_REG_VER:
-            val = s->version |
+            val = IOAPIC_VER_DEF |
                 ((IOAPIC_NUM_PINS - 1) << IOAPIC_VER_ENTRIES_SHIFT);
             break;
         default:
@@ -411,8 +411,7 @@  ioapic_mem_write(void *opaque, hwaddr addr, uint64_t val,
         }
         break;
     case IOAPIC_EOI:
-        /* Explicit EOI is only supported for IOAPIC version 0x20 */
-        if (size != 4 || s->version != 0x20) {
+        if (size != 4) {
             break;
         }
         ioapic_eoi_broadcast(val);
@@ -444,18 +443,10 @@  static void ioapic_machine_done_notify(Notifier *notifier, void *data)
 #endif
 }
 
-#define IOAPIC_VER_DEF 0x20
-
 static void ioapic_realize(DeviceState *dev, Error **errp)
 {
     IOAPICCommonState *s = IOAPIC_COMMON(dev);
 
-    if (s->version != 0x11 && s->version != 0x20) {
-        error_setg(errp, "IOAPIC only supports version 0x11 or 0x20 "
-                   "(default: 0x%x).", IOAPIC_VER_DEF);
-        return;
-    }
-
     memory_region_init_io(&s->io_memory, OBJECT(s), &ioapic_io_ops, s,
                           "ioapic", 0x1000);
 
@@ -476,10 +467,6 @@  static void ioapic_unrealize(DeviceState *dev)
     timer_free(s->delayed_ioapic_service_timer);
 }
 
-static const Property ioapic_properties[] = {
-    DEFINE_PROP_UINT8("version", IOAPICCommonState, version, IOAPIC_VER_DEF),
-};
-
 static void ioapic_class_init(ObjectClass *klass, const void *data)
 {
     IOAPICCommonClass *k = IOAPIC_COMMON_CLASS(klass);
@@ -493,7 +480,6 @@  static void ioapic_class_init(ObjectClass *klass, const void *data)
      */
     k->post_load = ioapic_update_kvm_routes;
     device_class_set_legacy_reset(dc, ioapic_reset_common);
-    device_class_set_props(dc, ioapic_properties);
 }
 
 static const TypeInfo ioapic_info = {
diff --git a/hw/intc/ioapic_common.c b/hw/intc/ioapic_common.c
index fce3486e519..8b3e2ba9384 100644
--- a/hw/intc/ioapic_common.c
+++ b/hw/intc/ioapic_common.c
@@ -83,7 +83,7 @@  static void ioapic_print_redtbl(GString *buf, IOAPICCommonState *s)
     int i;
 
     g_string_append_printf(buf, "ioapic0: ver=0x%x id=0x%02x sel=0x%02x",
-                           s->version, s->id, s->ioregsel);
+                           IOAPIC_VER_DEF, s->id, s->ioregsel);
     if (s->ioregsel) {
         g_string_append_printf(buf, " (redir[%u])\n",
                                (s->ioregsel - IOAPIC_REG_REDTBL_BASE) >> 1);