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Diffstat (limited to 'sys/amd64/isa/npx.c')
| -rw-r--r-- | sys/amd64/isa/npx.c | 554 |
1 files changed, 0 insertions, 554 deletions
diff --git a/sys/amd64/isa/npx.c b/sys/amd64/isa/npx.c deleted file mode 100644 index 08256a6..0000000 --- a/sys/amd64/isa/npx.c +++ /dev/null @@ -1,554 +0,0 @@ -/*- - * Copyright (c) 1990 William Jolitz. - * Copyright (c) 1991 The Regents of the University of California. - * All rights reserved. - * - * Redistribution and use in source and binary forms, with or without - * modification, are permitted provided that the following conditions - * are met: - * 1. Redistributions of source code must retain the above copyright - * notice, this list of conditions and the following disclaimer. - * 2. Redistributions in binary form must reproduce the above copyright - * notice, this list of conditions and the following disclaimer in the - * documentation and/or other materials provided with the distribution. - * 3. All advertising materials mentioning features or use of this software - * must display the following acknowledgement: - * This product includes software developed by the University of - * California, Berkeley and its contributors. - * 4. Neither the name of the University nor the names of its contributors - * may be used to endorse or promote products derived from this software - * without specific prior written permission. - * - * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND - * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE - * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE - * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE - * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL - * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS - * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) - * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT - * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY - * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF - * SUCH DAMAGE. - * - * from: @(#)npx.c 7.2 (Berkeley) 5/12/91 - * $Id$ - */ - -#include "npx.h" -#if NNPX > 0 - -#include "param.h" -#include "systm.h" -#include "conf.h" -#include "file.h" -#include "proc.h" -#include "machine/cpu.h" -#include "machine/pcb.h" -#include "machine/trap.h" -#include "ioctl.h" -#include "machine/specialreg.h" -#include "i386/isa/icu.h" -#include "i386/isa/isa_device.h" -#include "i386/isa/isa.h" - -/* - * 387 and 287 Numeric Coprocessor Extension (NPX) Driver. - */ - -#ifdef __GNUC__ - -#define disable_intr() __asm("cli") -#define enable_intr() __asm("sti") -#define fldcw(addr) __asm("fldcw %0" : : "m" (*addr)) -#define fnclex() __asm("fnclex") -#define fninit() __asm("fninit") -#define fnsave(addr) __asm("fnsave %0" : "=m" (*addr) : "0" (*addr)) -#define fnstcw(addr) __asm("fnstcw %0" : "=m" (*addr) : "0" (*addr)) -#define fnstsw(addr) __asm("fnstsw %0" : "=m" (*addr) : "0" (*addr)) -#define fp_divide_by_0() __asm("fldz; fld1; fdiv %st,%st(1); fwait") -#define frstor(addr) __asm("frstor %0" : : "m" (*addr)) -#define fwait() __asm("fwait") -#define read_eflags() ({u_long ef; \ - __asm("pushf; popl %0" : "=a" (ef)); \ - ef; }) -#define start_emulating() __asm("smsw %%ax; orb %0,%%al; lmsw %%ax" \ - : : "n" (CR0_TS) : "ax") -#define stop_emulating() __asm("clts") -#define write_eflags(ef) __asm("pushl %0; popf" : : "a" ((u_long) ef)) - -#else /* not __GNUC__ */ - -void disable_intr __P((void)); -void enable_intr __P((void)); -void fldcw __P((caddr_t addr)); -void fnclex __P((void)); -void fninit __P((void)); -void fnsave __P((caddr_t addr)); -void fnstcw __P((caddr_t addr)); -void fnstsw __P((caddr_t addr)); -void fp_divide_by_0 __P((void)); -void frstor __P((caddr_t addr)); -void fwait __P((void)); -u_long read_eflags __P((void)); -void start_emulating __P((void)); -void stop_emulating __P((void)); -void write_eflags __P((u_long ef)); - -#endif /* __GNUC__ */ - -typedef u_char bool_t; - -extern struct gate_descriptor idt[]; - -int npxdna __P((void)); -void npxexit __P((struct proc *p)); -void npxinit __P((u_int control)); -void npxintr __P((struct intrframe frame)); -void npxsave __P((struct save87 *addr)); -static int npxattach __P((struct isa_device *dvp)); -static int npxprobe __P((struct isa_device *dvp)); -static int npxprobe1 __P((struct isa_device *dvp)); - -struct isa_driver npxdriver = { - npxprobe, npxattach, "npx", -}; - -u_int npx0mask; -struct proc *npxproc; - -static bool_t npx_ex16; -static bool_t npx_exists; -static struct gate_descriptor npx_idt_probeintr; -static int npx_intrno; -static volatile u_int npx_intrs_while_probing; -static bool_t npx_irq13; -static volatile u_int npx_traps_while_probing; - -/* - * Special interrupt handlers. Someday intr0-intr15 will be used to count - * interrupts. We'll still need a special exception 16 handler. The busy - * latch stuff in probintr() can be moved to npxprobe(). - */ -void probeintr(void); -asm -(" - .text -_probeintr: - ss - incl _npx_intrs_while_probing - pushl %eax - movb $0x20,%al /* EOI (asm in strings loses cpp features) */ - outb %al,$0xa0 /* IO_ICU2 */ - outb %al,$0x20 /* IO_ICU1 */ - movb $0,%al - outb %al,$0xf0 /* clear BUSY# latch */ - popl %eax - iret -"); - -void probetrap(void); -asm -(" - .text -_probetrap: - ss - incl _npx_traps_while_probing - fnclex - iret -"); - -/* - * Probe routine. Initialize cr0 to give correct behaviour for [f]wait - * whether the device exists or not (XXX should be elsewhere). Set flags - * to tell npxattach() what to do. Modify device struct if npx doesn't - * need to use interrupts. Return 1 if device exists. - */ -static int -npxprobe(dvp) - struct isa_device *dvp; -{ - int result; - u_long save_eflags; - u_char save_icu1_mask; - u_char save_icu2_mask; - struct gate_descriptor save_idt_npxintr; - struct gate_descriptor save_idt_npxtrap; - /* - * This routine is now just a wrapper for npxprobe1(), to install - * special npx interrupt and trap handlers, to enable npx interrupts - * and to disable other interrupts. Someday isa_configure() will - * install suitable handlers and run with interrupts enabled so we - * won't need to do so much here. - */ - npx_intrno = NRSVIDT + ffs(dvp->id_irq) - 1; - save_eflags = read_eflags(); - disable_intr(); - save_icu1_mask = inb(IO_ICU1 + 1); - save_icu2_mask = inb(IO_ICU2 + 1); - save_idt_npxintr = idt[npx_intrno]; - save_idt_npxtrap = idt[16]; - outb(IO_ICU1 + 1, ~(IRQ_SLAVE | dvp->id_irq)); - outb(IO_ICU2 + 1, ~(dvp->id_irq >> 8)); - setidt(16, probetrap, SDT_SYS386TGT, SEL_KPL); - setidt(npx_intrno, probeintr, SDT_SYS386IGT, SEL_KPL); - npx_idt_probeintr = idt[npx_intrno]; - enable_intr(); - result = npxprobe1(dvp); - disable_intr(); - outb(IO_ICU1 + 1, save_icu1_mask); - outb(IO_ICU2 + 1, save_icu2_mask); - idt[npx_intrno] = save_idt_npxintr; - idt[16] = save_idt_npxtrap; - write_eflags(save_eflags); - return (result); -} - -static int -npxprobe1(dvp) - struct isa_device *dvp; -{ - int control; - int status; -#ifdef lint - npxintr(); -#endif - /* - * Partially reset the coprocessor, if any. Some BIOS's don't reset - * it after a warm boot. - */ - outb(0xf1, 0); /* full reset on some systems, NOP on others */ - outb(0xf0, 0); /* clear BUSY# latch */ - /* - * Prepare to trap all ESC (i.e., NPX) instructions and all WAIT - * instructions. We must set the CR0_MP bit and use the CR0_TS - * bit to control the trap, because setting the CR0_EM bit does - * not cause WAIT instructions to trap. It's important to trap - * WAIT instructions - otherwise the "wait" variants of no-wait - * control instructions would degenerate to the "no-wait" variants - * after FP context switches but work correctly otherwise. It's - * particularly important to trap WAITs when there is no NPX - - * otherwise the "wait" variants would always degenerate. - * - * Try setting CR0_NE to get correct error reporting on 486DX's. - * Setting it should fail or do nothing on lesser processors. - */ - load_cr0(rcr0() | CR0_MP | CR0_NE); - /* - * But don't trap while we're probing. - */ - stop_emulating(); - /* - * Finish resetting the coprocessor, if any. If there is an error - * pending, then we may get a bogus IRQ13, but probeintr() will handle - * it OK. Bogus halts have never been observed, but we enabled - * IRQ13 and cleared the BUSY# latch early to handle them anyway. - */ - fninit(); - DELAY(1000); /* wait for any IRQ13 (fwait might hang) */ -#ifdef DIAGNOSTIC - if (npx_intrs_while_probing != 0) - printf("fninit caused %u bogus npx interrupt(s)\n", - npx_intrs_while_probing); - if (npx_traps_while_probing != 0) - printf("fninit caused %u bogus npx trap(s)\n", - npx_traps_while_probing); -#endif - /* - * Check for a status of mostly zero. - */ - status = 0x5a5a; - fnstsw(&status); - if ((status & 0xb8ff) == 0) { - /* - * Good, now check for a proper control word. - */ - control = 0x5a5a; - fnstcw(&control); - if ((control & 0x1f3f) == 0x033f) { - npx_exists = 1; - /* - * We have an npx, now divide by 0 to see if exception - * 16 works. - */ - control &= ~(1 << 2); /* enable divide by 0 trap */ - fldcw(&control); - npx_traps_while_probing = npx_intrs_while_probing = 0; - fp_divide_by_0(); - if (npx_traps_while_probing != 0) { - /* - * Good, exception 16 works. - */ - npx_ex16 = 1; - dvp->id_irq = 0; /* zap the interrupt */ - /* - * special return value to flag that we do not - * actually use any I/O registers - */ - return (-1); - } - if (npx_intrs_while_probing != 0) { - /* - * Bad, we are stuck with IRQ13. - */ - npx_irq13 = 1; - npx0mask = dvp->id_irq; /* npxattach too late */ - return (IO_NPXSIZE); - } - /* - * Worse, even IRQ13 is broken. Use emulator. - */ - } - } - /* - * Probe failed, but we want to get to npxattach to initialize the - * emulator and say that it has been installed. XXX handle devices - * that aren't really devices better. - */ - dvp->id_irq = 0; - /* - * special return value to flag that we do not - * actually use any I/O registers - */ - return (-1); -} - -/* - * Attach routine - announce which it is, and wire into system - */ -int -npxattach(dvp) - struct isa_device *dvp; -{ - if (!npx_ex16 && !npx_irq13) { - if (npx_exists) - printf("npx%d: Error reporting broken, using 387 emulator\n",dvp->id_unit); - else - printf("npx%d: 387 Emulator\n",dvp->id_unit); - } - npxinit(__INITIAL_NPXCW__); - return (1); /* XXX unused */ -} - -/* - * Initialize floating point unit. - */ -void -npxinit(control) - u_int control; -{ - struct save87 dummy; - - if (!npx_exists) - return; - /* - * fninit has the same h/w bugs as fnsave. Use the detoxified - * fnsave to throw away any junk in the fpu. fnsave initializes - * the fpu and sets npxproc = NULL as important side effects. - */ - npxsave(&dummy); - stop_emulating(); - fldcw(&control); - if (curpcb != NULL) - fnsave(&curpcb->pcb_savefpu); - start_emulating(); -} - -/* - * Free coprocessor (if we have it). - */ -void -npxexit(p) - struct proc *p; -{ - - if (p == npxproc) { - start_emulating(); - npxproc = NULL; - } -} - -/* - * Record the FPU state and reinitialize it all except for the control word. - * Then generate a SIGFPE. - * - * Reinitializing the state allows naive SIGFPE handlers to longjmp without - * doing any fixups. - * - * XXX there is currently no way to pass the full error state to signal - * handlers, and if this is a nested interrupt there is no way to pass even - * a status code! So there is no way to have a non-naive SIGFPE handler. At - * best a handler could do an fninit followed by an fldcw of a static value. - * fnclex would be of little use because it would leave junk on the FPU stack. - * Returning from the handler would be even less safe than usual because - * IRQ13 exception handling makes exceptions even less precise than usual. - */ -void -npxintr(frame) - struct intrframe frame; -{ - int code; - - if (npxproc == NULL || !npx_exists) { - /* XXX no %p in stand/printf.c. Cast to quiet gcc -Wall. */ - printf("npxintr: npxproc = %lx, curproc = %lx, npx_exists = %d\n", - (u_long) npxproc, (u_long) curproc, npx_exists); - panic("npxintr from nowhere"); - } - if (npxproc != curproc) { - printf("npxintr: npxproc = %lx, curproc = %lx, npx_exists = %d\n", - (u_long) npxproc, (u_long) curproc, npx_exists); - panic("npxintr from non-current process"); - } - /* - * Save state. This does an implied fninit. It had better not halt - * the cpu or we'll hang. - */ - outb(0xf0, 0); - fnsave(&curpcb->pcb_savefpu); - fwait(); - /* - * Restore control word (was clobbered by fnsave). - */ - fldcw(&curpcb->pcb_savefpu.sv_env.en_cw); - fwait(); - /* - * Remember the exception status word and tag word. The current - * (almost fninit'ed) fpu state is in the fpu and the exception - * state just saved will soon be junk. However, the implied fninit - * doesn't change the error pointers or register contents, and we - * preserved the control word and will copy the status and tag - * words, so the complete exception state can be recovered. - */ - curpcb->pcb_savefpu.sv_ex_sw = curpcb->pcb_savefpu.sv_env.en_sw; - curpcb->pcb_savefpu.sv_ex_tw = curpcb->pcb_savefpu.sv_env.en_tw; - - /* - * Pass exception to process. - */ - if (ISPL(frame.if_cs) == SEL_UPL) { - /* - * Interrupt is essentially a trap, so we can afford to call - * the SIGFPE handler (if any) as soon as the interrupt - * returns. - * - * XXX little or nothing is gained from this, and plenty is - * lost - the interrupt frame has to contain the trap frame - * (this is otherwise only necessary for the rescheduling trap - * in doreti, and the frame for that could easily be set up - * just before it is used). - */ - curproc->p_regs = (int *)&frame.if_es; - curpcb->pcb_flags |= FM_TRAP; /* used by sendsig */ -#ifdef notyet - /* - * Encode the appropriate code for detailed information on - * this exception. - */ - code = XXX_ENCODE(curpcb->pcb_savefpu.sv_ex_sw); -#else - code = 0; /* XXX */ -#endif - trapsignal(curproc, SIGFPE, code); - curpcb->pcb_flags &= ~FM_TRAP; - } else { - /* - * Nested interrupt. These losers occur when: - * o an IRQ13 is bogusly generated at a bogus time, e.g.: - * o immediately after an fnsave or frstor of an - * error state. - * o a couple of 386 instructions after - * "fstpl _memvar" causes a stack overflow. - * These are especially nasty when combined with a - * trace trap. - * o an IRQ13 occurs at the same time as another higher- - * priority interrupt. - * - * Treat them like a true async interrupt. - */ - psignal(npxproc, SIGFPE); - } -} - -/* - * Implement device not available (DNA) exception - * - * It would be better to switch FP context here (only). This would require - * saving the state in the proc table instead of in the pcb. - */ -int -npxdna() -{ - if (!npx_exists) - return (0); - if (npxproc != NULL) { - printf("npxdna: npxproc = %lx, curproc = %lx\n", - (u_long) npxproc, (u_long) curproc); - panic("npxdna"); - } - stop_emulating(); - /* - * Record new context early in case frstor causes an IRQ13. - */ - npxproc = curproc; - /* - * The following frstor may cause an IRQ13 when the state being - * restored has a pending error. The error will appear to have been - * triggered by the current (npx) user instruction even when that - * instruction is a no-wait instruction that should not trigger an - * error (e.g., fnclex). On at least one 486 system all of the - * no-wait instructions are broken the same as frstor, so our - * treatment does not amplify the breakage. On at least one - * 386/Cyrix 387 system, fnclex works correctly while frstor and - * fnsave are broken, so our treatment breaks fnclex if it is the - * first FPU instruction after a context switch. - */ - frstor(&curpcb->pcb_savefpu); - - return (1); -} - -/* - * Wrapper for fnsave instruction to handle h/w bugs. If there is an error - * pending, then fnsave generates a bogus IRQ13 on some systems. Force - * any IRQ13 to be handled immediately, and then ignore it. This routine is - * often called at splhigh so it must not use many system services. In - * particular, it's much easier to install a special handler than to - * guarantee that it's safe to use npxintr() and its supporting code. - */ -void -npxsave(addr) - struct save87 *addr; -{ - u_char icu1_mask; - u_char icu2_mask; - u_char old_icu1_mask; - u_char old_icu2_mask; - struct gate_descriptor save_idt_npxintr; - - disable_intr(); - old_icu1_mask = inb(IO_ICU1 + 1); - old_icu2_mask = inb(IO_ICU2 + 1); - save_idt_npxintr = idt[npx_intrno]; - outb(IO_ICU1 + 1, old_icu1_mask & ~(IRQ_SLAVE | npx0mask)); - outb(IO_ICU2 + 1, old_icu2_mask & ~(npx0mask >> 8)); - idt[npx_intrno] = npx_idt_probeintr; - enable_intr(); - stop_emulating(); - fnsave(addr); - fwait(); - start_emulating(); - npxproc = NULL; - disable_intr(); - icu1_mask = inb(IO_ICU1 + 1); /* masks may have changed */ - icu2_mask = inb(IO_ICU2 + 1); - outb(IO_ICU1 + 1, - (icu1_mask & ~npx0mask) | (old_icu1_mask & npx0mask)); - outb(IO_ICU2 + 1, - (icu2_mask & ~(npx0mask >> 8)) - | (old_icu2_mask & (npx0mask >> 8))); - idt[npx_intrno] = save_idt_npxintr; - enable_intr(); /* back to usual state */ -} - -#endif /* NNPX > 0 */ |
