🆕 HPET驱动

2025-06-22 15:23:23 +00:00 · 2022-04-08 12:20:53 +08:00
parent 8bf4da2afa
commit d887f9a0f7
12 changed files with 259 additions and 36 deletions
--- a/kernel/driver/timers/HPET/HPET.c
+++ b/kernel/driver/timers/HPET/HPET.c
@ -0,0 +1,102 @@
+#include "HPET.h"
+#include <common/kprint.h>
+#include <mm/mm.h>
+#include <driver/interrupt/apic/apic.h>
+
+static struct acpi_HPET_description_table_t *hpet_table;
+static uint64_t HPET_REG_BASE = 0;
+static uint32_t HPET_COUNTER_CLK_PERIOD = 0; // 主计数器时间精度（单位：飞秒）
+static double HPET_freq = 0;                 // 主计时器频率
+static uint8_t HPET_NUM_TIM_CAP = 0;         // 定时器数量
+
+extern struct rtc_time_t rtc_now; // 导出全局墙上时钟
+
+enum
+{
+    GCAP_ID = 0x00,
+    GEN_CONF = 0x10,
+    GINTR_STA = 0x20,
+    MAIN_CNT = 0xf0,
+    TIM0_CONF = 0x100,
+    TIM0_COMP = 0x108,
+    TIM1_CONF = 0x120,
+    TIM1_COMP = 0x128,
+    TIM2_CONF = 0x140,
+    TIM2_COMP = 0x148,
+    TIM3_CONF = 0x160,
+    TIM3_COMP = 0x168,
+    TIM4_CONF = 0x180,
+    TIM4_COMP = 0x188,
+    TIM5_CONF = 0x1a0,
+    TIM5_COMP = 0x1a8,
+    TIM6_CONF = 0x1c0,
+    TIM6_COMP = 0x1c8,
+    TIM7_CONF = 0x1e0,
+    TIM7_COMP = 0x1e8,
+};
+
+hardware_intr_controller HPET_intr_controller =
+    {
+        .enable = apic_ioapic_enable,
+        .disable = apic_ioapic_disable,
+        .install = apic_ioapic_install,
+        .uninstall = apic_ioapic_uninstall,
+        .ack = apic_ioapic_edge_ack,
+};
+
+void HPET_handler(uint64_t number, uint64_t param, struct pt_regs *regs)
+{
+    //printk_color(ORANGE, BLACK, "(HPET)");
+    switch (param)
+    {
+    case 0:
+        rtc_get_cmos_time(&rtc_now);
+        break;
+
+    default:
+        break;
+    }
+}
+
+int HPET_init()
+{
+    // 从acpi获取hpet结构体
+    ul hpet_table_addr = 0;
+    acpi_iter_SDT(acpi_get_HPET, &hpet_table_addr);
+    if (hpet_table_addr == 0)
+    {
+        kerror("HPET Not Found On This Computer!");
+        return E_HPET_INIT_FAILED;
+    }
+    hpet_table = (struct acpi_HPET_description_table_t *)hpet_table_addr;
+    // 由于这段内存与io/apic的映射在同一物理页内，因此不需要重复映射
+    HPET_REG_BASE = SPECIAL_MEMOEY_MAPPING_VIRT_ADDR_BASE + hpet_table->address;
+
+    // 读取计时精度并计算频率
+    uint64_t tmp;
+    tmp = *(uint64_t *)(HPET_REG_BASE + GCAP_ID);
+    HPET_COUNTER_CLK_PERIOD = (tmp >> 32) & 0xffffffff;
+    HPET_freq = 1.0 * 1e15 / HPET_COUNTER_CLK_PERIOD;
+    HPET_NUM_TIM_CAP = (tmp >> 8) & 0x1f; // 读取计时器数量
+
+    kinfo("HPET CLK_PERIOD=%#03lx Frequency=%f", HPET_COUNTER_CLK_PERIOD, HPET_freq);
+    struct apic_IO_APIC_RTE_entry entry;
+    // 使用I/O APIC 的IRQ2接收hpet定时器0的中断
+    apic_make_rte_entry(&entry, 34, IO_APIC_FIXED, DEST_PHYSICAL, IDLE, POLARITY_HIGH, IRR_RESET, EDGE_TRIGGER, MASKED, 0);
+    // 注册中断
+    irq_register(34, &entry, &HPET_handler, 0, &HPET_intr_controller, "HPET0");
+
+    *(uint64_t *)(HPET_REG_BASE + GEN_CONF) = 3; // 置位旧设备中断路由兼容标志位、定时器组使能标志位
+    io_mfence();
+
+    *(uint64_t *)(HPET_REG_BASE + TIM0_CONF) = 0x004c; // 设置定时器0为周期定时，边沿触发，投递到IO APIC的2号引脚（这里有点绕，写的是8259的引脚号，但是因为禁用了8259，因此会被路由到IO APIC的2号引脚）
+    io_mfence();
+    *(uint64_t *)(HPET_REG_BASE + TIM0_COMP) = HPET_freq; // 1s触发一次中断
+    io_mfence();
+
+    rtc_get_cmos_time(&rtc_now);
+    *(uint64_t *)(HPET_REG_BASE + MAIN_CNT) = 0;
+    io_mfence();
+
+    
+}