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Diffstat (limited to 'include/x86/pic.h')
| -rw-r--r-- | include/x86/pic.h | 139 |
1 files changed, 139 insertions, 0 deletions
diff --git a/include/x86/pic.h b/include/x86/pic.h new file mode 100644 index 0000000..d4fa93b --- /dev/null +++ b/include/x86/pic.h @@ -0,0 +1,139 @@ +/** +** @file pic.h +** +** @author Warren R. Carithers +** @author K. Reek +** +** Definitions of constants and macros for the Intel 8259 Programmable +** Interrupt Controller. +** +*/ + +#ifndef X86PIC_H_ +#define X86PIC_H_ + +/* +** Our expected configuration is two PICs, with the secondary connected +** through the IRQ2 pin of the primary. +*/ + +/* +** Port addresses for the command port and interrupt mask register port +** for both the primary and secondary PICs. +*/ +#define PIC1_CMD 0x20 // primary command +#define PIC1_DATA (PIC1_CMD + 1) // primary data / int mask register +#define PIC2_CMD 0xA0 // secondary command +#define PIC2_DATA (PIC2_CMD + 1) // secondary data / int mask register + +/* +** Initialization Command Word (ICW) definitions +** +** Initialization sequence: +** ICW1 Init command is sent to each command port. +** ICW2 vector commands are sent to the data ports. +** If "cascade mode" was selected, send ICW3 commands to the data ports. +** If "need ICW4" was selected, send ICW4 commands to the data ports. +** +** Following that sequence, the PIC is ready to accept interrupts; +** it will also accept Output Command Words (OCWs) to the data ports. +** +** PIC1_* defines are intended for the primary PIC +** PIC2_* defines are intended for the secondary PIC +** PIC_* defines are sent to both PICs +*/ + +/* +** ICW1: initialization, send to command port +*/ +#define PIC_CW1_INIT 0x10 // start initialization sequence +#define PIC_CW1_NEED4 0x01 // ICW4 will also be set +#define PIC_CW1_SINGLE 0x02 // select single (vs. cascade) mode +#define PIC_CW1_INTVAL 0x04 // set call interval to 4 (vs. 8) +#define PIC_CW1_LEVEL 0x08 // use level-triggered mode (vs. edge) + +/* +** ICW2: interrupt vector base offsets, send to data port +*/ +#define PIC1_CW2_VECBASE 0x20 // IRQ0 int vector number +#define PIC2_CW2_VECBASE 0x28 // IRQ8 int vector number + +/* +** ICW3: secondary::primary attachment, send to data port +*/ +#define PIC1_CW3_SEC_IRQ2 0x04 // bit mask: secondary is on pin 2 +#define PIC2_CW3_SEC_ID 0x02 // integer: secondary id + +/* +** ICW4: operating mode, send to data port +*/ +#define PIC_CW4_PM86 0x01 // 8086 mode (vs. 8080/8085) +#define PIC_CW4_AUTOEOI 0x02 // do auto eoi's +#define PIC_CW4_UNBUF 0x00 // unbuffered mode +#define PIC_CW4_SEC_BUF 0x08 // put secondary in buffered mode +#define PIC_CW4_PRI_BUF 0x0C // put primary in buffered mode +#define PIC_CW4_SFNMODE 0x10 // "special fully nested" mode + +/* +** Operation Control Words (OCWs) +** +** After the init sequence, can send these +*/ + +/* +** OCW1: interrupt mask; send to data port +*/ +#define PIC_MASK_NONE 0x00 // allow all interrupts +#define PIC_MASK_NO_IRQ0 0x01 // prevent IRQ0 interrupts +#define PIC_MASK_NO_IRQ1 0x02 // prevent IRQ1 interrupts +#define PIC_MASK_NO_IRQ2 0x04 // prevent IRQ2 interrupts +#define PIC_MASK_NO_IRQ3 0x08 // prevent IRQ3 interrupts +#define PIC_MASK_NO_IRQ4 0x10 // prevent IRQ4 interrupts +#define PIC_MASK_NO_IRQ5 0x20 // prevent IRQ5 interrupts +#define PIC_MASK_NO_IRQ6 0x40 // prevent IRQ6 interrupts +#define PIC_MASK_NO_IRQ7 0x80 // prevent IRQ7 interrupts +#define PIC_MASK_ALL 0xff // prevent all interrupts + +/* +** OCW2: EOI control, interrupt level; send to command port +*/ +#define PIC_LVL_0 0x00 // act on IRQ level 0 +#define PIC_LVL_1 0x01 // act on IRQ level 1 +#define PIC_LVL_2 0x02 // act on IRQ level 2 +#define PIC_LVL_3 0x03 // act on IRQ level 3 +#define PIC_LVL_4 0x04 // act on IRQ level 4 +#define PIC_LVL_5 0x05 // act on IRQ level 5 +#define PIC_LVL_6 0x06 // act on IRQ level 6 +#define PIC_LVL_7 0x07 // act on IRQ level 7 + +#define PIC_EOI_NON_SPEC 0x20 // non-specific EOI command +# define PIC_EOI PIC_EOI_NON_SPEC + +#define PIC_EOI_SPEC 0x60 // specific EOI command +# define PIC_SEOI PIC_EOI_SPEC +# define PIC_SEOI_LVL0 (PIC_EOI_SPEC | PIC_LVL_0) +# define PIC_SEOI_LVL1 (PIC_EOI_SPEC | PIC_LVL_1) +# define PIC_SEOI_LVL2 (PIC_EOI_SPEC | PIC_LVL_2) +# define PIC_SEOI_LVL3 (PIC_EOI_SPEC | PIC_LVL_3) +# define PIC_SEOI_LVL4 (PIC_EOI_SPEC | PIC_LVL_4) +# define PIC_SEOI_LVL5 (PIC_EOI_SPEC | PIC_LVL_5) +# define PIC_SEOI_LVL6 (PIC_EOI_SPEC | PIC_LVL_6) +# define PIC_SEOI_LVL7 (PIC_EOI_SPEC | PIC_LVL_7) + +#define PIC_EOI_ROT_NONSP 0xa0 // rotate on non-spec EOI cmd +#define PIC_EOI_SET_ROT_AUTO 0x80 // set "rotate in auto EOI mode" +#define PIC_EOI_CLR_ROT_AUTO 0x00 // clear "rotate in auto EOI mode" +#define PIC_EOI_ROT_SPEC 0xe0 // rotate on spec EOI cmd (+ level) +#define PIC_EOI_SET_PRIO 0xc0 // set priority (+ level) +#define PIC_EOI_NOP 0x40 // no operation + +/* +** OCW3: read requests, special mask mode; send to command port +*/ +#define PIC_READIRR 0x0a // read the IR register +#define PIC_READISR 0x0b // read the IS register +#define PIC_POLL 0x0c // poll +#define PIC_MASK_RESET 0x48 // reset special mask mode +#define PIC_MASK_SET 0x68 // set special mask mode + +#endif |