From: acevest <zhaoyanbai@126.com>
Date: Sat, 3 Jan 2026 04:02:16 +0000 (+0800)
Subject: 简单读取HPET相关寄存器
X-Git-Url: http://repos.zhaoyanbai.com/Mou_128.png?a=commitdiff_plain;h=d06cfebae51129b88dbf8654045e13f2ffdf0051;p=kernel.git

简单读取HPET相关寄存器
---

diff --git a/Makefile b/Makefile
index 4349e0e..f752989 100644
--- a/Makefile
+++ b/Makefile
@@ -82,7 +82,7 @@ ${KERNELBIN}: print_flags ${OBJS}
 	@echo 'LD ${KERNELBIN}'
 	@${LD} ${LDFLAGS} $(OBJS) -o $@ > $(SYSTEMMAP)
 	@nm -a $@ > kernel.sym
-# rm kernel/setup.c.o
+	rm kernel/setup.c.o
 
 %.S.o: %.S ${HEADER_FILES}
 	@echo 'CC $<'
diff --git a/include/apic.h b/include/apic.h
index 54d9035..7d3aea9 100644
--- a/include/apic.h
+++ b/include/apic.h
@@ -28,6 +28,9 @@
 #define LAPIC_PPR 0xA0
 #define LAPIC_EOI 0xB0
 #define LAPIC_LDR 0xD0
+
+// Destination Format Register
+// x2APIC模式下，不再支持平坦模式，仅剩集群模式，以至于x2APIC模式废除了DFR寄存器
 #define LAPIC_DFR 0xE0
 
 // 伪中断向量寄存器
diff --git a/kernel/apic.c b/kernel/apic.c
index 7e7c050..55b0b18 100644
--- a/kernel/apic.c
+++ b/kernel/apic.c
@@ -310,6 +310,35 @@ void ioapic_init() {
     ioapic_rte_write(IOAPIC_RTE(1), 0x20 + 1);
     irq_set_chip(0x00, &ioapic_chip);
     irq_set_chip(0x01, &ioapic_chip);
+
+    // HPTC: High Precision Timer Control Register
+    // bit[1:0] 地址映射范围选择域
+    //       取值      地址映射范围
+    //        00: 0xFED00000 - 0xFED003FF
+    //        01: 0xFED01000 - 0xFED013FF
+    //        10: 0xFED02000 - 0xFED023FF
+    //        11: 0xFED03000 - 0xFED033FF
+    // bit[7] 地址映射使能标志位，用于控制HPET设备访问地址的开启与否
+    //        只有它置位时芯片组才会将HPET配置寄存器映射到内存空间
+    uint32_t* pHPTC = (uint32_t*)((uint8_t*)rcba_virt_base + 0x3404);
+    printk("HPTC: %08x\n", *pHPTC);
+    *pHPTC = (1 << 7) | (0x00);
+    printk("HPTC: %08x\n", *pHPTC);
+
+    vaddr_t hpet_base = (vaddr_t)ioremap(0xFED00000, 0x3FF);
+    printk("HPET base %08x mapped to %08x\n", 0xFED00000, hpet_base);
+
+    uint64_t GCAP_ID = 0;
+    GCAP_ID = *(volatile uint32_t*)(hpet_base + 4);
+    GCAP_ID <<= 32;
+    GCAP_ID |= *(volatile uint32_t*)(hpet_base + 0);
+    printk("GCAP_ID: %016x\n", GCAP_ID);
+
+    uint64_t iddd = *(volatile uint64_t*)(hpet_base + 0);
+    printk("GCAP_ID: %016x\n", iddd);
+    // asm("cli;hlt;");
+    // TODO
+    // iounmap(hpet_base);
 }
 
 void disable_i8259();
diff --git a/qemu.sh b/qemu.sh
index efa0e87..0efdfce 100755
--- a/qemu.sh
+++ b/qemu.sh
@@ -39,7 +39,7 @@ qemu-system-i386 \
     # nc -U /tmp/qemu-monitor.sock
 
     # -d int,cpu_reset \
-
+    # -monitor unix:/tmp/qemu-monitor.sock,server,nowait \
     # -machine pc-q35-9.2  \
     # -cpu qemu32,+apic \
     # -cpu qemu32,+x2apic \