diff --git a/paw/stos/head/arch/amd64/lapicreg.h b/paw/stos/head/arch/amd64/lapicreg.h new file mode 100644 index 0000000..e605163 --- /dev/null +++ b/paw/stos/head/arch/amd64/lapicreg.h @@ -0,0 +1,64 @@ +/* + * Copyright (c) 2026, Chloe M. + * Provided under the BSD-3 clause. + * + * Description: Local APIC registers + * Author: Chloe M. + */ + +#ifndef _MACHINE_LAPICREG_H_ +#define _MACHINE_LAPICREG_H_ 1 + +#include + +/* LAPIC register offsets */ +#define LAPIC_ID 0x0020U /* ID Register */ +#define LAPIC_VERSION 0x0030U /* Version Register */ +#define LAPIC_TPR 0x0080U /* Task Priority Register */ +#define LAPIC_APR 0x0090U /* Arbitration Priority Register */ +#define LAPIC_PPR 0x00A0U /* Processor Priority Register */ +#define LAPIC_EOI 0x00B0U /* End Of Interrupt Register */ +#define LAPIC_RRD 0x00C0U /* Remote Read Register */ +#define LAPIC_LDR 0x00D0U /* Logical Destination Register */ +#define LAPIC_DFR 0x00E0U /* Destination Format Register */ +#define LAPIC_SVR 0x00F0U /* Spurious Vector Register */ +#define LAPIC_ISR 0x0100U /* In service register (max=0x0220) */ +#define LAPIC_TMR 0x0180U /* Trigger Mode Register (max=0x0220) */ +#define LAPIC_IRR 0x0200U /* Interrupt Request Register (max=0x0270) */ +#define LAPIC_ERR 0x0280U /* Error Status Register */ +#define LAPIC_ICRLO 0x0300U /* Interrupt Command Low Register */ +#define LAPIC_ICRHI 0x0310U /* Interrupt Command High Register */ +#define LAPIC_LVT_TMR 0x0320U /* LVT Timer Register */ +#define LAPIC_DCR 0x03E0U /* Divide Configuration Register (for timer) */ +#define LAPIC_INIT_CNT 0x0380U /* Initial Count Register (for timer) */ +#define LAPIC_CUR_CNT 0x0390U /* Current Count Register (for timer) */ + +/* + * The x2APIC register space is accessed via + * RDMSR/WRMSR instructions. The below defines + * the base MSR address for the register space. + */ +#define x2APIC_MSR_BASE 0x00000800 + +/* + * To hardware enable, OR the value of the IA32_APIC_BASE + * MSR with LAPIC_HW_ENABLE and rewrite it. + * + * To software enable, OR the value of the SVR with + * LAPIC_SW_ENABLE and rewrite it. + * + * LAPIC_SW_ENABLE has the low 8 bits set as some hardware + * requires the spurious vector to be hardwired to 1s so + * we'll go with that to be safe. + */ +#define LAPIC_HW_ENABLE BIT(11) +#define LAPIC_SW_ENABLE (BIT(8) | 0xFF) +#define x2APIC_ENABLE_SHIFT 10 + +/* LVT bits */ +#define LAPIC_LVT_MASK BIT(16) +#define LVT_TMR_ONESHOT 0x00 +#define LVT_TMR_PERIODIC 0x01 +#define LVT_TMR_TSC_DEADLINE 0x02 + +#endif /* !_MACHINE_LAPICREG_H_ */