From: Daniel Jacobowitz Date: Sun, 27 Aug 2006 11:42:10 +0000 (+0100) Subject: [ARM] 3749/3: Correct VFP single/double conversion emulation X-Git-Tag: v2.6.18-rc6~60^2~7 X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=c29ecac18cb740ae845db14963ac586c53962453;p=linux-2.6 [ARM] 3749/3: Correct VFP single/double conversion emulation Patch from Daniel Jacobowitz The fcvtsd/fcvtds emulation was left behind when the numbering of double precision registers was changed from 0-30 to 0-15. Both conversion instructions were writing their results to the wrong register. Also, the conversion instructions should stop after the first element even if a vector length is specified. Signed-off-by: Daniel Jacobowitz Signed-off-by: Russell King --- diff --git a/arch/arm/vfp/vfpdouble.c b/arch/arm/vfp/vfpdouble.c index 009038c811..021581680e 100644 --- a/arch/arm/vfp/vfpdouble.c +++ b/arch/arm/vfp/vfpdouble.c @@ -1127,7 +1127,7 @@ u32 vfp_double_cpdo(u32 inst, u32 fpscr) { u32 op = inst & FOP_MASK; u32 exceptions = 0; - unsigned int dd = vfp_get_dd(inst); + unsigned int dest; unsigned int dn = vfp_get_dn(inst); unsigned int dm = vfp_get_dm(inst); unsigned int vecitr, veclen, vecstride; @@ -1136,11 +1136,21 @@ u32 vfp_double_cpdo(u32 inst, u32 fpscr) veclen = fpscr & FPSCR_LENGTH_MASK; vecstride = (1 + ((fpscr & FPSCR_STRIDE_MASK) == FPSCR_STRIDE_MASK)) * 2; + /* + * fcvtds takes an sN register number as destination, not dN. + * It also always operates on scalars. + */ + if ((inst & FEXT_MASK) == FEXT_FCVT) { + veclen = 0; + dest = vfp_get_sd(inst); + } else + dest = vfp_get_dd(inst); + /* * If destination bank is zero, vector length is always '1'. * ARM DDI0100F C5.1.3, C5.3.2. */ - if (FREG_BANK(dd) == 0) + if (FREG_BANK(dest) == 0) veclen = 0; pr_debug("VFP: vecstride=%u veclen=%u\n", vecstride, @@ -1153,16 +1163,20 @@ u32 vfp_double_cpdo(u32 inst, u32 fpscr) for (vecitr = 0; vecitr <= veclen; vecitr += 1 << FPSCR_LENGTH_BIT) { u32 except; - if (op == FOP_EXT) + if (op == FOP_EXT && (inst & FEXT_MASK) == FEXT_FCVT) + pr_debug("VFP: itr%d (s%u) = op[%u] (d%u)\n", + vecitr >> FPSCR_LENGTH_BIT, + dest, dn, dm); + else if (op == FOP_EXT) pr_debug("VFP: itr%d (d%u) = op[%u] (d%u)\n", vecitr >> FPSCR_LENGTH_BIT, - dd, dn, dm); + dest, dn, dm); else pr_debug("VFP: itr%d (d%u) = (d%u) op[%u] (d%u)\n", vecitr >> FPSCR_LENGTH_BIT, - dd, dn, FOP_TO_IDX(op), dm); + dest, dn, FOP_TO_IDX(op), dm); - except = fop(dd, dn, dm, fpscr); + except = fop(dest, dn, dm, fpscr); pr_debug("VFP: itr%d: exceptions=%08x\n", vecitr >> FPSCR_LENGTH_BIT, except); @@ -1180,7 +1194,7 @@ u32 vfp_double_cpdo(u32 inst, u32 fpscr) * we encounter an exception. We continue. */ - dd = FREG_BANK(dd) + ((FREG_IDX(dd) + vecstride) & 6); + dest = FREG_BANK(dest) + ((FREG_IDX(dest) + vecstride) & 6); dn = FREG_BANK(dn) + ((FREG_IDX(dn) + vecstride) & 6); if (FREG_BANK(dm) != 0) dm = FREG_BANK(dm) + ((FREG_IDX(dm) + vecstride) & 6); diff --git a/arch/arm/vfp/vfpsingle.c b/arch/arm/vfp/vfpsingle.c index dae2c2f460..5bbd5d1c8a 100644 --- a/arch/arm/vfp/vfpsingle.c +++ b/arch/arm/vfp/vfpsingle.c @@ -514,10 +514,6 @@ static u32 vfp_single_fcvtd(int dd, int unused, s32 m, u32 fpscr) else vdd.exponent = vsm.exponent + (1023 - 127); - /* - * Technically, if bit 0 of dd is set, this is an invalid - * instruction. However, we ignore this for efficiency. - */ return vfp_double_normaliseround(dd, &vdd, fpscr, exceptions, "fcvtd"); pack_nan: @@ -1174,7 +1170,7 @@ u32 vfp_single_cpdo(u32 inst, u32 fpscr) { u32 op = inst & FOP_MASK; u32 exceptions = 0; - unsigned int sd = vfp_get_sd(inst); + unsigned int dest; unsigned int sn = vfp_get_sn(inst); unsigned int sm = vfp_get_sm(inst); unsigned int vecitr, veclen, vecstride; @@ -1183,11 +1179,23 @@ u32 vfp_single_cpdo(u32 inst, u32 fpscr) veclen = fpscr & FPSCR_LENGTH_MASK; vecstride = 1 + ((fpscr & FPSCR_STRIDE_MASK) == FPSCR_STRIDE_MASK); + /* + * fcvtsd takes a dN register number as destination, not sN. + * Technically, if bit 0 of dd is set, this is an invalid + * instruction. However, we ignore this for efficiency. + * It also only operates on scalars. + */ + if ((inst & FEXT_MASK) == FEXT_FCVT) { + veclen = 0; + dest = vfp_get_dd(inst); + } else + dest = vfp_get_sd(inst); + /* * If destination bank is zero, vector length is always '1'. * ARM DDI0100F C5.1.3, C5.3.2. */ - if (FREG_BANK(sd) == 0) + if (FREG_BANK(dest) == 0) veclen = 0; pr_debug("VFP: vecstride=%u veclen=%u\n", vecstride, @@ -1201,15 +1209,18 @@ u32 vfp_single_cpdo(u32 inst, u32 fpscr) s32 m = vfp_get_float(sm); u32 except; - if (op == FOP_EXT) + if (op == FOP_EXT && (inst & FEXT_MASK) == FEXT_FCVT) + pr_debug("VFP: itr%d (d%u) = op[%u] (s%u=%08x)\n", + vecitr >> FPSCR_LENGTH_BIT, dest, sn, sm, m); + else if (op == FOP_EXT) pr_debug("VFP: itr%d (s%u) = op[%u] (s%u=%08x)\n", - vecitr >> FPSCR_LENGTH_BIT, sd, sn, sm, m); + vecitr >> FPSCR_LENGTH_BIT, dest, sn, sm, m); else pr_debug("VFP: itr%d (s%u) = (s%u) op[%u] (s%u=%08x)\n", - vecitr >> FPSCR_LENGTH_BIT, sd, sn, + vecitr >> FPSCR_LENGTH_BIT, dest, sn, FOP_TO_IDX(op), sm, m); - except = fop(sd, sn, m, fpscr); + except = fop(dest, sn, m, fpscr); pr_debug("VFP: itr%d: exceptions=%08x\n", vecitr >> FPSCR_LENGTH_BIT, except); @@ -1227,7 +1238,7 @@ u32 vfp_single_cpdo(u32 inst, u32 fpscr) * we encounter an exception. We continue. */ - sd = FREG_BANK(sd) + ((FREG_IDX(sd) + vecstride) & 7); + dest = FREG_BANK(dest) + ((FREG_IDX(dest) + vecstride) & 7); sn = FREG_BANK(sn) + ((FREG_IDX(sn) + vecstride) & 7); if (FREG_BANK(sm) != 0) sm = FREG_BANK(sm) + ((FREG_IDX(sm) + vecstride) & 7);