diff options
Diffstat (limited to 'sys/amd64/isa/vector.S')
| -rw-r--r-- | sys/amd64/isa/vector.S | 360 |
1 files changed, 360 insertions, 0 deletions
diff --git a/sys/amd64/isa/vector.S b/sys/amd64/isa/vector.S new file mode 100644 index 0000000..7135ae7 --- /dev/null +++ b/sys/amd64/isa/vector.S @@ -0,0 +1,360 @@ +/* + * from: vector.s, 386BSD 0.1 unknown origin + * $Id: vector.s,v 1.6 1994/01/10 23:15:09 ache Exp $ + */ + +#include "i386/isa/icu.h" +#include "i386/isa/isa.h" +#include "vector.h" + +#define ICU_EOI 0x20 /* XXX - define elsewhere */ + +#define IRQ_BIT(irq_num) (1 << ((irq_num) % 8)) +#define IRQ_BYTE(irq_num) ((irq_num) / 8) + +#ifdef AUTO_EOI_1 +#define ENABLE_ICU1 /* use auto-EOI to reduce i/o */ +#else +#define ENABLE_ICU1 \ + movb $ICU_EOI,%al ; /* as soon as possible send EOI ... */ \ + FASTER_NOP ; /* ... ASAP ... */ \ + outb %al,$IO_ICU1 /* ... to clear in service bit */ +#endif + +#ifdef AUTO_EOI_2 +/* + * The data sheet says no auto-EOI on slave, but it sometimes works. + */ +#define ENABLE_ICU1_AND_2 ENABLE_ICU1 +#else +#define ENABLE_ICU1_AND_2 \ + movb $ICU_EOI,%al ; /* as above */ \ + FASTER_NOP ; \ + outb %al,$IO_ICU2 ; /* but do second icu first */ \ + FASTER_NOP ; \ + outb %al,$IO_ICU1 /* then first icu */ +#endif + +#ifdef FAST_INTR_HANDLER_USES_ES +#define ACTUALLY_PUSHED 1 +#define MAYBE_MOVW_AX_ES movl %ax,%es +#define MAYBE_POPL_ES popl %es +#define MAYBE_PUSHL_ES pushl %es +#else +/* + * We can usually skip loading %es for fastintr handlers. %es should + * only be used for string instructions, and fastintr handlers shouldn't + * do anything slow enough to justify using a string instruction. + */ +#define ACTUALLY_PUSHED 0 +#define MAYBE_MOVW_AX_ES +#define MAYBE_POPL_ES +#define MAYBE_PUSHL_ES +#endif + +/* + * Macros for interrupt interrupt entry, call to handler, and exit. + * + * XXX - the interrupt frame is set up to look like a trap frame. This is + * usually a waste of time. The only interrupt handlers that want a frame + * are the clock handler (it wants a clock frame), the npx handler (it's + * easier to do right all in assembler). The interrupt return routine + * needs a trap frame for rare AST's (it could easily convert the frame). + * The direct costs of setting up a trap frame are two pushl's (error + * code and trap number), an addl to get rid of these, and pushing and + * popping the call-saved regs %esi, %edi and %ebp twice, The indirect + * costs are making the driver interface nonuniform so unpending of + * interrupts is more complicated and slower (call_driver(unit) would + * be easier than ensuring an interrupt frame for all handlers. Finally, + * there are some struct copies in the npx handler and maybe in the clock + * handler that could be avoided by working more with pointers to frames + * instead of frames. + * + * XXX - should we do a cld on every system entry to avoid the requirement + * for scattered cld's? + * + * Coding notes for *.s: + * + * If possible, avoid operations that involve an operand size override. + * Word-sized operations might be smaller, but the operand size override + * makes them slower on on 486's and no faster on 386's unless perhaps + * the instruction pipeline is depleted. E.g., + * + * Use movl to seg regs instead of the equivalent but more descriptive + * movw - gas generates an irelevant (slower) operand size override. + * + * Use movl to ordinary regs in preference to movw and especially + * in preference to movz[bw]l. Use unsigned (long) variables with the + * top bits clear instead of unsigned short variables to provide more + * opportunities for movl. + * + * If possible, use byte-sized operations. They are smaller and no slower. + * + * Use (%reg) instead of 0(%reg) - gas generates larger code for the latter. + * + * If the interrupt frame is made more flexible, INTR can push %eax first + * and decide the ipending case with less overhead, e.g., by avoiding + * loading segregs. + */ + +#define FAST_INTR(unit, irq_num, id_num, handler, enable_icus) \ + pushl %eax ; /* save only call-used registers */ \ + pushl %ecx ; \ + pushl %edx ; \ + pushl %ds ; \ + MAYBE_PUSHL_ES ; \ + movl $KDSEL,%eax ; \ + movl %ax,%ds ; \ + MAYBE_MOVW_AX_ES ; \ + FAKE_MCOUNT((4+ACTUALLY_PUSHED)*4(%esp)) ; \ + pushl $unit ; \ + call handler ; /* do the work ASAP */ \ + enable_icus ; /* (re)enable ASAP (helps edge trigger?) */ \ + addl $4,%esp ; \ + incl _cnt+V_INTR ; /* book-keeping can wait */ \ + incl _intrcnt_actv + (id_num) * 4 ; \ + movl _cpl,%eax ; /* are we unmasking pending HWIs or SWIs? */ \ + notl %eax ; \ + andl _ipending,%eax ; \ + jne 1f ; /* yes, handle them */ \ + MEXITCOUNT ; \ + MAYBE_POPL_ES ; \ + popl %ds ; \ + popl %edx ; \ + popl %ecx ; \ + popl %eax ; \ + iret ; \ +; \ + ALIGN_TEXT ; \ +1: ; \ + movl _cpl,%eax ; \ + movl $HWI_MASK|SWI_MASK,_cpl ; /* limit nesting ... */ \ + sti ; /* ... to do this as early as possible */ \ + MAYBE_POPL_ES ; /* discard most of thin frame ... */ \ + popl %ecx ; /* ... original %ds ... */ \ + popl %edx ; \ + xchgl %eax,(1+ACTUALLY_PUSHED)*4(%esp) ; /* orig %eax; save cpl */ \ + pushal ; /* build fat frame (grrr) ... */ \ + pushl %ecx ; /* ... actually %ds ... */ \ + pushl %es ; \ + movl $KDSEL,%eax ; \ + movl %ax,%es ; \ + movl (2+8+0)*4(%esp),%ecx ; /* ... %ecx from thin frame ... */ \ + movl %ecx,(2+6)*4(%esp) ; /* ... to fat frame ... */ \ + movl (2+8+1)*4(%esp),%eax ; /* ... cpl from thin frame */ \ + pushl %eax ; \ + subl $4,%esp ; /* junk for unit number */ \ + MEXITCOUNT ; \ + jmp _doreti + +#define INTR(unit, irq_num, id_num, mask, handler, icu, enable_icus, reg, stray) \ + pushl $0 ; /* dumby error code */ \ + pushl $0 ; /* dumby trap type */ \ + pushal ; \ + pushl %ds ; /* save our data and extra segments ... */ \ + pushl %es ; \ + movl $KDSEL,%eax ; /* ... and reload with kernel's own ... */ \ + movl %ax,%ds ; /* ... early for obsolete reasons */ \ + movl %ax,%es ; \ + movb _imen + IRQ_BYTE(irq_num),%al ; \ + orb $IRQ_BIT(irq_num),%al ; \ + movb %al,_imen + IRQ_BYTE(irq_num) ; \ + FASTER_NOP ; \ + outb %al,$icu+1 ; \ + enable_icus ; \ + incl _cnt+V_INTR ; /* tally interrupts */ \ + movl _cpl,%eax ; \ + testb $IRQ_BIT(irq_num),%reg ; \ + jne 2f ; \ +1: ; \ + FAKE_MCOUNT(12*4(%esp)) ; /* XXX late to avoid double count */ \ + incl _intrcnt_actv + (id_num) * 4 ; \ + movl _cpl,%eax ; \ + pushl %eax ; \ + pushl $unit ; \ + orl mask,%eax ; \ + movl %eax,_cpl ; \ + sti ; \ + call handler ; \ + movb _imen + IRQ_BYTE(irq_num),%al ; \ + andb $~IRQ_BIT(irq_num),%al ; \ + movb %al,_imen + IRQ_BYTE(irq_num) ; \ + FASTER_NOP ; \ + outb %al,$icu+1 ; \ + MEXITCOUNT ; \ + /* We could usually avoid the following jmp by inlining some of */ \ + /* _doreti, but it's probably better to use less cache. */ \ + jmp _doreti ; \ +; \ + ALIGN_TEXT ; \ +2: ; \ + /* XXX skip mcounting here to avoid double count */ \ + movl $1b,%eax ; /* register resume address */ \ + /* XXX - someday do it at attach time */ \ + movl %eax,ihandlers + (irq_num) * 4 ; \ + orb $IRQ_BIT(irq_num),_ipending + IRQ_BYTE(irq_num) ; \ + popl %es ; \ + popl %ds ; \ + popal ; \ + addl $4+4,%esp ; \ + iret + +/* + * vector.h has defined a macro 'BUILD_VECTORS' containing a big list of info + * about vectors, including a submacro 'BUILD_VECTOR' that operates on the + * info about each vector. We redefine 'BUILD_VECTOR' to expand the info + * in different ways. Here we expand it to a list of interrupt handlers. + * This order is of course unimportant. Elsewhere we expand it to inline + * linear search code for which the order is a little more important and + * concatenating the code with no holes is very important. + * + * XXX - now there is BUILD_FAST_VECTOR as well as BUILD_VECTOR. + * + * The info consists of the following items for each vector: + * + * name (identifier): name of the vector; used to build labels + * unit (expression): unit number to call the device driver with + * irq_num (number): number of the IRQ to handled (0-15) + * id_num (number): uniq numeric id for handler (assigned by config) + * mask (blank-ident): priority mask used + * handler (blank-ident): interrupt handler to call + * icu_num (number): (1 + irq_num / 8) converted for label building + * icu_enables (number): 1 for icu_num == 1, 1_AND_2 for icu_num == 2 + * reg (blank-ident): al for icu_num == 1, ah for icu_num == 2 + * + * 'irq_num' is converted in several ways at config time to get around + * limitations in cpp. The macros have blanks after commas iff they would + * not mess up identifiers and numbers. + */ + +#undef BUILD_FAST_VECTOR +#define BUILD_FAST_VECTOR(name, unit, irq_num, id_num, mask, handler, \ + icu_num, icu_enables, reg) \ + .globl handler ; \ + .text ; \ + .globl _V/**/name ; \ + SUPERALIGN_TEXT ; \ +_V/**/name: ; \ + FAST_INTR(unit, irq_num,id_num, handler, ENABLE_ICU/**/icu_enables) + +#undef BUILD_VECTOR +#define BUILD_VECTOR(name, unit, irq_num, id_num, mask, handler, \ + icu_num, icu_enables, reg) \ + .globl handler ; \ + .text ; \ + .globl _V/**/name ; \ + SUPERALIGN_TEXT ; \ +_V/**/name: ; \ + INTR(unit,irq_num, id_num, mask, handler, IO_ICU/**/icu_num, \ + ENABLE_ICU/**/icu_enables, reg,) + +MCOUNT_LABEL(bintr) + BUILD_VECTORS + + /* hardware interrupt catcher (IDT 32 - 47) */ + .globl _isa_strayintr + +#define STRAYINTR(irq_num, icu_num, icu_enables, reg) \ +IDTVEC(intr/**/irq_num) ; \ + INTR(irq_num,irq_num,irq_num, _high_imask, _isa_strayintr, \ + IO_ICU/**/icu_num, ENABLE_ICU/**/icu_enables, reg,stray) + +/* + * XXX - the mask (1 << 2) == IRQ_SLAVE will be generated for IRQ 2, instead + * of the mask IRQ2 (defined as IRQ9 == (1 << 9)). But IRQ 2 "can't happen". + * In fact, all stray interrupts "can't happen" except for bugs. The + * "stray" IRQ 7 is documented behaviour of the 8259. It happens when there + * is a glitch on any of its interrupt inputs. Does it really interrupt when + * IRQ 7 is masked? + * + * XXX - unpend doesn't work for these, it sends them to the real handler. + * + * XXX - the race bug during initialization may be because I changed the + * order of switching from the stray to the real interrupt handler to before + * enabling interrupts. The old order looked unsafe but maybe it is OK with + * the stray interrupt handler installed. But these handlers only reduce + * the window of vulnerability - it is still open at the end of + * isa_configure(). + * + * XXX - many comments are stale. + */ + + STRAYINTR(0,1,1, al) + STRAYINTR(1,1,1, al) + STRAYINTR(2,1,1, al) + STRAYINTR(3,1,1, al) + STRAYINTR(4,1,1, al) + STRAYINTR(5,1,1, al) + STRAYINTR(6,1,1, al) + STRAYINTR(7,1,1, al) + STRAYINTR(8,2,1_AND_2, ah) + STRAYINTR(9,2,1_AND_2, ah) + STRAYINTR(10,2,1_AND_2, ah) + STRAYINTR(11,2,1_AND_2, ah) + STRAYINTR(12,2,1_AND_2, ah) + STRAYINTR(13,2,1_AND_2, ah) + STRAYINTR(14,2,1_AND_2, ah) + STRAYINTR(15,2,1_AND_2, ah) +#if 0 + INTRSTRAY(255, _highmask, 255) ; call _isa_strayintr ; INTREXIT2 +#endif +MCOUNT_LABEL(eintr) + +/* + * These are the interrupt counters, I moved them here from icu.s so that + * they are with the name table. rgrimes + * + * There are now lots of counters, this has been redone to work with + * Bruce Evans intr-0.1 code, which I modified some more to make it all + * work with vmstat. + */ + .data +ihandlers: /* addresses of interrupt handlers */ + .space NHWI*4 /* actually resumption addresses for HWI's */ + .long swi_tty, swi_net, 0, 0, 0, 0, 0, 0 + .long 0, 0, 0, 0, 0, 0, swi_clock, swi_ast +imasks: /* masks for interrupt handlers */ + .space NHWI*4 /* padding; HWI masks are elsewhere */ + .long SWI_TTY_MASK, SWI_NET_MASK, 0, 0, 0, 0, 0, 0 + .long 0, 0, 0, 0, 0, 0, SWI_CLOCK_MASK, SWI_AST_MASK + + .globl _intrcnt +_intrcnt: /* used by vmstat to calc size of table */ + .globl _intrcnt_bad7 +_intrcnt_bad7: .space 4 /* glitches on irq 7 */ + .globl _intrcnt_bad15 +_intrcnt_bad15: .space 4 /* glitches on irq 15 */ + .globl _intrcnt_stray +_intrcnt_stray: .space 4 /* total count of stray interrupts */ + .globl _intrcnt_actv +_intrcnt_actv: .space NR_REAL_INT_HANDLERS * 4 /* active interrupts */ + .globl _eintrcnt +_eintrcnt: /* used by vmstat to calc size of table */ + +/* + * Build the interrupt name table for vmstat + */ + +#undef BUILD_FAST_VECTOR +#define BUILD_FAST_VECTOR BUILD_VECTOR + +#undef BUILD_VECTOR +#define BUILD_VECTOR(name, unit, irq_num, id_num, mask, handler, \ + icu_num, icu_enables, reg) \ + .ascii "name irq" ; \ + .asciz "irq_num" +/* + * XXX - use the __STRING and __CONCAT macros from <sys/cdefs.h> to stringize + * and concatenate names above and elsewhere. Note that __CONCAT doesn't + * work when nested. + */ + + .text + .globl _intrnames, _eintrnames +_intrnames: + BUILD_VECTOR(bad,,7,,,,,,) + BUILD_VECTOR(bad,,15,,,,,,) + BUILD_VECTOR(stray,,,,,,,,) + BUILD_VECTORS + +_eintrnames: |
