From 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Sat, 16 Apr 2005 15:20:36 -0700 Subject: Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip! --- arch/sparc/kernel/muldiv.c | 240 +++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 240 insertions(+) create mode 100644 arch/sparc/kernel/muldiv.c (limited to 'arch/sparc/kernel/muldiv.c') diff --git a/arch/sparc/kernel/muldiv.c b/arch/sparc/kernel/muldiv.c new file mode 100644 index 000000000000..37b9a4942232 --- /dev/null +++ b/arch/sparc/kernel/muldiv.c @@ -0,0 +1,240 @@ +/* $Id: muldiv.c,v 1.5 1997/12/15 20:07:20 ecd Exp $ + * muldiv.c: Hardware multiply/division illegal instruction trap + * for sun4c/sun4 (which do not have those instructions) + * + * Copyright (C) 1996 Jakub Jelinek (jj@sunsite.mff.cuni.cz) + * Copyright (C) 1996 David S. Miller (davem@caip.rutgers.edu) + * + * 2004-12-25 Krzysztof Helt (krzysztof.h1@wp.pl) + * - fixed registers constrains in inline assembly declarations + */ + +#include +#include +#include +#include +#include +#include +#include + +/* #define DEBUG_MULDIV */ + +static inline int has_imm13(int insn) +{ + return (insn & 0x2000); +} + +static inline int is_foocc(int insn) +{ + return (insn & 0x800000); +} + +static inline int sign_extend_imm13(int imm) +{ + return imm << 19 >> 19; +} + +static inline void advance(struct pt_regs *regs) +{ + regs->pc = regs->npc; + regs->npc += 4; +} + +static inline void maybe_flush_windows(unsigned int rs1, unsigned int rs2, + unsigned int rd) +{ + if(rs2 >= 16 || rs1 >= 16 || rd >= 16) { + /* Wheee... */ + __asm__ __volatile__("save %sp, -0x40, %sp\n\t" + "save %sp, -0x40, %sp\n\t" + "save %sp, -0x40, %sp\n\t" + "save %sp, -0x40, %sp\n\t" + "save %sp, -0x40, %sp\n\t" + "save %sp, -0x40, %sp\n\t" + "save %sp, -0x40, %sp\n\t" + "restore; restore; restore; restore;\n\t" + "restore; restore; restore;\n\t"); + } +} + +#define fetch_reg(reg, regs) ({ \ + struct reg_window __user *win; \ + register unsigned long ret; \ + \ + if (!(reg)) ret = 0; \ + else if ((reg) < 16) { \ + ret = regs->u_regs[(reg)]; \ + } else { \ + /* Ho hum, the slightly complicated case. */ \ + win = (struct reg_window __user *)regs->u_regs[UREG_FP];\ + if (get_user (ret, &win->locals[(reg) - 16])) return -1;\ + } \ + ret; \ +}) + +static inline int +store_reg(unsigned int result, unsigned int reg, struct pt_regs *regs) +{ + struct reg_window __user *win; + + if (!reg) + return 0; + if (reg < 16) { + regs->u_regs[reg] = result; + return 0; + } else { + /* need to use put_user() in this case: */ + win = (struct reg_window __user *) regs->u_regs[UREG_FP]; + return (put_user(result, &win->locals[reg - 16])); + } +} + +extern void handle_hw_divzero (struct pt_regs *regs, unsigned long pc, + unsigned long npc, unsigned long psr); + +/* Should return 0 if mul/div emulation succeeded and SIGILL should + * not be issued. + */ +int do_user_muldiv(struct pt_regs *regs, unsigned long pc) +{ + unsigned int insn; + int inst; + unsigned int rs1, rs2, rdv; + + if (!pc) + return -1; /* This happens to often, I think */ + if (get_user (insn, (unsigned int __user *)pc)) + return -1; + if ((insn & 0xc1400000) != 0x80400000) + return -1; + inst = ((insn >> 19) & 0xf); + if ((inst & 0xe) != 10 && (inst & 0xe) != 14) + return -1; + + /* Now we know we have to do something with umul, smul, udiv or sdiv */ + rs1 = (insn >> 14) & 0x1f; + rs2 = insn & 0x1f; + rdv = (insn >> 25) & 0x1f; + if (has_imm13(insn)) { + maybe_flush_windows(rs1, 0, rdv); + rs2 = sign_extend_imm13(insn); + } else { + maybe_flush_windows(rs1, rs2, rdv); + rs2 = fetch_reg(rs2, regs); + } + rs1 = fetch_reg(rs1, regs); + switch (inst) { + case 10: /* umul */ +#ifdef DEBUG_MULDIV + printk ("unsigned muldiv: 0x%x * 0x%x = ", rs1, rs2); +#endif + __asm__ __volatile__ ("\n\t" + "mov %0, %%o0\n\t" + "call .umul\n\t" + " mov %1, %%o1\n\t" + "mov %%o0, %0\n\t" + "mov %%o1, %1\n\t" + : "=r" (rs1), "=r" (rs2) + : "0" (rs1), "1" (rs2) + : "o0", "o1", "o2", "o3", "o4", "o5", "o7", "cc"); +#ifdef DEBUG_MULDIV + printk ("0x%x%08x\n", rs2, rs1); +#endif + if (store_reg(rs1, rdv, regs)) + return -1; + regs->y = rs2; + break; + case 11: /* smul */ +#ifdef DEBUG_MULDIV + printk ("signed muldiv: 0x%x * 0x%x = ", rs1, rs2); +#endif + __asm__ __volatile__ ("\n\t" + "mov %0, %%o0\n\t" + "call .mul\n\t" + " mov %1, %%o1\n\t" + "mov %%o0, %0\n\t" + "mov %%o1, %1\n\t" + : "=r" (rs1), "=r" (rs2) + : "0" (rs1), "1" (rs2) + : "o0", "o1", "o2", "o3", "o4", "o5", "o7", "cc"); +#ifdef DEBUG_MULDIV + printk ("0x%x%08x\n", rs2, rs1); +#endif + if (store_reg(rs1, rdv, regs)) + return -1; + regs->y = rs2; + break; + case 14: /* udiv */ +#ifdef DEBUG_MULDIV + printk ("unsigned muldiv: 0x%x%08x / 0x%x = ", regs->y, rs1, rs2); +#endif + if (!rs2) { +#ifdef DEBUG_MULDIV + printk ("DIVISION BY ZERO\n"); +#endif + handle_hw_divzero (regs, pc, regs->npc, regs->psr); + return 0; + } + __asm__ __volatile__ ("\n\t" + "mov %2, %%o0\n\t" + "mov %0, %%o1\n\t" + "mov %%g0, %%o2\n\t" + "call __udivdi3\n\t" + " mov %1, %%o3\n\t" + "mov %%o1, %0\n\t" + "mov %%o0, %1\n\t" + : "=r" (rs1), "=r" (rs2) + : "r" (regs->y), "0" (rs1), "1" (rs2) + : "o0", "o1", "o2", "o3", "o4", "o5", "o7", + "g1", "g2", "g3", "cc"); +#ifdef DEBUG_MULDIV + printk ("0x%x\n", rs1); +#endif + if (store_reg(rs1, rdv, regs)) + return -1; + break; + case 15: /* sdiv */ +#ifdef DEBUG_MULDIV + printk ("signed muldiv: 0x%x%08x / 0x%x = ", regs->y, rs1, rs2); +#endif + if (!rs2) { +#ifdef DEBUG_MULDIV + printk ("DIVISION BY ZERO\n"); +#endif + handle_hw_divzero (regs, pc, regs->npc, regs->psr); + return 0; + } + __asm__ __volatile__ ("\n\t" + "mov %2, %%o0\n\t" + "mov %0, %%o1\n\t" + "mov %%g0, %%o2\n\t" + "call __divdi3\n\t" + " mov %1, %%o3\n\t" + "mov %%o1, %0\n\t" + "mov %%o0, %1\n\t" + : "=r" (rs1), "=r" (rs2) + : "r" (regs->y), "0" (rs1), "1" (rs2) + : "o0", "o1", "o2", "o3", "o4", "o5", "o7", + "g1", "g2", "g3", "cc"); +#ifdef DEBUG_MULDIV + printk ("0x%x\n", rs1); +#endif + if (store_reg(rs1, rdv, regs)) + return -1; + break; + } + if (is_foocc (insn)) { + regs->psr &= ~PSR_ICC; + if ((inst & 0xe) == 14) { + /* ?div */ + if (rs2) regs->psr |= PSR_V; + } + if (!rs1) regs->psr |= PSR_Z; + if (((int)rs1) < 0) regs->psr |= PSR_N; +#ifdef DEBUG_MULDIV + printk ("psr muldiv: %08x\n", regs->psr); +#endif + } + advance(regs); + return 0; +} -- cgit v1.2.2