hw/intc/aspeed: Support setting different register size

Currently, the size of the regs array is 0x2000, which is too large. So far,
it only use GICINT128 - GICINT134, and the offsets from 0 to 0x1000 are unused.
To save code size, introduce a new class attribute "reg_size" to set the
different register sizes for the INTC models in AST2700 and add a regs
sub-region in the memory container.

Signed-off-by: Jamin Lin <jamin_lin@aspeedtech.com>
Reviewed-by: Cédric Le Goater <clg@redhat.com>
Link: https://lore.kernel.org/qemu-devel/20250307035945.3698802-5-jamin_lin@aspeedtech.com
Signed-off-by: Cédric Le Goater <clg@redhat.com>

hw/intc/aspeed_intc.c

@@ -120,13 +120,6 @@ static uint64_t aspeed_intc_read(void *opaque, hwaddr offset, unsigned int size)
     uint32_t reg = offset >> 2;
     uint32_t value = 0;
 
-    if (reg >= ASPEED_INTC_NR_REGS) {
-        qemu_log_mask(LOG_GUEST_ERROR,
-                      "%s: Out-of-bounds read at offset 0x%" HWADDR_PRIx "\n",
-                      __func__, offset);
-        return 0;
-    }
-
     value = s->regs[reg];
     trace_aspeed_intc_read(offset, size, value);
 
@@ -143,13 +136,6 @@ static void aspeed_intc_write(void *opaque, hwaddr offset, uint64_t data,
     uint32_t change;
     uint32_t irq;
 
-    if (reg >= ASPEED_INTC_NR_REGS) {
-        qemu_log_mask(LOG_GUEST_ERROR,
-                      "%s: Out-of-bounds write at offset 0x%" HWADDR_PRIx "\n",
-                      __func__, offset);
-        return;
-    }
-
     trace_aspeed_intc_write(offset, size, data);
 
     switch (reg) {
@@ -288,8 +274,9 @@ static void aspeed_intc_instance_init(Object *obj)
 static void aspeed_intc_reset(DeviceState *dev)
 {
     AspeedINTCState *s = ASPEED_INTC(dev);
+    AspeedINTCClass *aic = ASPEED_INTC_GET_CLASS(s);
 
-    memset(s->regs, 0, ASPEED_INTC_NR_REGS << 2);
+    memset(s->regs, 0, aic->nr_regs << 2);
     memset(s->enable, 0, sizeof(s->enable));
     memset(s->mask, 0, sizeof(s->mask));
     memset(s->pending, 0, sizeof(s->pending));
@@ -307,9 +294,9 @@ static void aspeed_intc_realize(DeviceState *dev, Error **errp)
 
     sysbus_init_mmio(sbd, &s->iomem_container);
 
-    s->regs = g_new(uint32_t, ASPEED_INTC_NR_REGS);
+    s->regs = g_new(uint32_t, aic->nr_regs);
     memory_region_init_io(&s->iomem, OBJECT(s), &aspeed_intc_ops, s,
-                          TYPE_ASPEED_INTC ".regs", ASPEED_INTC_NR_REGS << 2);
+                          TYPE_ASPEED_INTC ".regs", aic->nr_regs << 2);
 
     memory_region_add_subregion(&s->iomem_container, 0x0, &s->iomem);
 
@@ -361,6 +348,7 @@ static void aspeed_2700_intc_class_init(ObjectClass *klass, void *data)
     aic->num_lines = 32;
     aic->num_ints = 9;
     aic->mem_size = 0x4000;
+    aic->nr_regs = 0x2000 >> 2;
 }
 
 static const TypeInfo aspeed_2700_intc_info = {

include/hw/intc/aspeed_intc.h

@@ -16,7 +16,6 @@
 #define TYPE_ASPEED_2700_INTC TYPE_ASPEED_INTC "-ast2700"
 OBJECT_DECLARE_TYPE(AspeedINTCState, AspeedINTCClass, ASPEED_INTC)
 
-#define ASPEED_INTC_NR_REGS (0x2000 >> 2)
 #define ASPEED_INTC_NR_INTS 9
 
 struct AspeedINTCState {
@@ -42,6 +41,7 @@ struct AspeedINTCClass {
     uint32_t num_lines;
     uint32_t num_ints;
     uint64_t mem_size;
+    uint64_t nr_regs;
 };
 
 #endif /* ASPEED_INTC_H */