[01/10] i386/fw_cfg: move hpet_cfg definition to hpet.c

Commit Message

Zhao Liu Jan. 25, 2025, 12:51 p.m. UTC

HPET device needs to access and update hpet_cfg variable, but now it is
defined in hw/i386/fw_cfg.c and Rust code can't access it.

Move hpet_cfg definition to hpet.c (and rename it to hpet_fw_cfg). This
allows Rust HPET device implements its own global hpet_fw_cfg variable,
and will further reduce the use of unsafe C code access and calls in the
Rust HPET implementation.

Signed-off-by: Zhao Liu <[e-mail]>
---
 hw/i386/fw_cfg.c        |  4 +---
 hw/timer/hpet.c         | 14 ++++++++------
 include/hw/timer/hpet.h |  2 +-
 3 files changed, 10 insertions(+), 10 deletions(-)

Patch

diff --git a/hw/i386/fw_cfg.c b/hw/i386/fw_cfg.c
index d2cb08715a21..546de63123e6 100644
--- a/hw/i386/fw_cfg.c
+++ b/hw/i386/fw_cfg.c
@@ -26,8 +26,6 @@ 
 #include CONFIG_DEVICES
 #include "target/i386/cpu.h"
 
-struct hpet_fw_config hpet_cfg = {.count = UINT8_MAX};
-
 const char *fw_cfg_arch_key_name(uint16_t key)
 {
     static const struct {
@@ -153,7 +151,7 @@  FWCfgState *fw_cfg_arch_create(MachineState *ms,
     PCMachineState *pcms =
         (PCMachineState *)object_dynamic_cast(OBJECT(ms), TYPE_PC_MACHINE);
     if (pcms && pcms->hpet_enabled) {
-        fw_cfg_add_bytes(fw_cfg, FW_CFG_HPET, &hpet_cfg, sizeof(hpet_cfg));
+        fw_cfg_add_bytes(fw_cfg, FW_CFG_HPET, &hpet_fw_cfg, sizeof(hpet_fw_cfg));
     }
 #endif
 
diff --git a/hw/timer/hpet.c b/hw/timer/hpet.c
index 92b6d509edda..f2e2d83a3f67 100644
--- a/hw/timer/hpet.c
+++ b/hw/timer/hpet.c
@@ -40,6 +40,8 @@ 
 #include "qom/object.h"
 #include "trace.h"
 
+struct hpet_fw_config hpet_fw_cfg = {.count = UINT8_MAX};
+
 #define HPET_MSI_SUPPORT        0
 
 OBJECT_DECLARE_SIMPLE_TYPE(HPETState, HPET)
@@ -655,8 +657,8 @@  static void hpet_reset(DeviceState *d)
     s->hpet_counter = 0ULL;
     s->hpet_offset = 0ULL;
     s->config = 0ULL;
-    hpet_cfg.hpet[s->hpet_id].event_timer_block_id = (uint32_t)s->capability;
-    hpet_cfg.hpet[s->hpet_id].address = sbd->mmio[0].addr;
+    hpet_fw_cfg.hpet[s->hpet_id].event_timer_block_id = (uint32_t)s->capability;
+    hpet_fw_cfg.hpet[s->hpet_id].address = sbd->mmio[0].addr;
 
     /* to document that the RTC lowers its output on reset as well */
     s->rtc_irq_level = 0;
@@ -698,17 +700,17 @@  static void hpet_realize(DeviceState *dev, Error **errp)
     if (!s->intcap) {
         warn_report("Hpet's intcap not initialized");
     }
-    if (hpet_cfg.count == UINT8_MAX) {
+    if (hpet_fw_cfg.count == UINT8_MAX) {
         /* first instance */
-        hpet_cfg.count = 0;
+        hpet_fw_cfg.count = 0;
     }
 
-    if (hpet_cfg.count == 8) {
+    if (hpet_fw_cfg.count == 8) {
         error_setg(errp, "Only 8 instances of HPET is allowed");
         return;
     }
 
-    s->hpet_id = hpet_cfg.count++;
+    s->hpet_id = hpet_fw_cfg.count++;
 
     for (i = 0; i < HPET_NUM_IRQ_ROUTES; i++) {
         sysbus_init_irq(sbd, &s->irqs[i]);
diff --git a/include/hw/timer/hpet.h b/include/hw/timer/hpet.h
index 71e8c62453d1..c2656f7f0bef 100644
--- a/include/hw/timer/hpet.h
+++ b/include/hw/timer/hpet.h
@@ -73,7 +73,7 @@  struct hpet_fw_config
     struct hpet_fw_entry hpet[8];
 } QEMU_PACKED;
 
-extern struct hpet_fw_config hpet_cfg;
+extern struct hpet_fw_config hpet_fw_cfg;
 
 #define TYPE_HPET "hpet"