Re: [PATCH RFC v2 06/70] MIPS: mm: Add MIPS R6 instruction encodings

[David Daney <ddaney.cavm@gmail.com>]

On 01/16/2015 02:48 AM, Markos Chandras wrote:
> From: Leonid Yegoshin <Leonid.Yegoshin@imgtec.com>
>
> MIPS R6 defines new opcodes for ll, sc, cache and pref instructions
> so we need to take these into consideration in the micro-assembler.
>
> Signed-off-by: Leonid Yegoshin <Leonid.Yegoshin@imgtec.com>
> Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
> ---
>   arch/mips/include/uapi/asm/inst.h |  9 ++++++---

We should probably split changes to uapi/asm/inst.h in to a separate 
patch from the patches to the kernel proper.

The fact that it changes (extends) a userspace ABI, makes it a candidate 
for being a standalone patch.

David Daney

>   arch/mips/mm/uasm-mips.c          | 32 ++++++++++++++++++++++++++++++++
>   2 files changed, 38 insertions(+), 3 deletions(-)
>
> diff --git a/arch/mips/include/uapi/asm/inst.h b/arch/mips/include/uapi/asm/inst.h
> index 89c22433b1c6..5c9e14a903af 100644
> --- a/arch/mips/include/uapi/asm/inst.h
> +++ b/arch/mips/include/uapi/asm/inst.h
> @@ -83,9 +83,12 @@ enum spec3_op {
>   	swe_op    = 0x1f, bshfl_op  = 0x20,
>   	swle_op   = 0x21, swre_op   = 0x22,
>   	prefe_op  = 0x23, dbshfl_op = 0x24,
> -	lbue_op   = 0x28, lhue_op   = 0x29,
> -	lbe_op    = 0x2c, lhe_op    = 0x2d,
> -	lle_op    = 0x2e, lwe_op    = 0x2f,
> +	cache6_op = 0x25, sc6_op    = 0x26,
> +	scd6_op   = 0x27, lbue_op   = 0x28,
> +	lhue_op   = 0x29, lbe_op    = 0x2c,
> +	lhe_op    = 0x2d, lle_op    = 0x2e,
> +	lwe_op    = 0x2f, pref6_op  = 0x35,
> +	ll6_op    = 0x36, lld6_op   = 0x37,
>   	rdhwr_op  = 0x3b
>   };
>
> diff --git a/arch/mips/mm/uasm-mips.c b/arch/mips/mm/uasm-mips.c
> index 8e02291cfc0c..7bb0d4ce2de8 100644
> --- a/arch/mips/mm/uasm-mips.c
> +++ b/arch/mips/mm/uasm-mips.c
> @@ -38,6 +38,14 @@
>   	 | (e) << RE_SH						\
>   	 | (f) << FUNC_SH)
>
> +/* This macro sets the non-variable bits of an R6 instruction. */
> +#define M6(a, b, c, d, e)					\
> +	((a) << OP_SH						\
> +	 | (b) << RS_SH						\
> +	 | (c) << RT_SH						\
> +	 | (d) << SIMM9_SH					\
> +	 | (e) << FUNC_SH)
> +
>   /* Define these when we are not the ISA the kernel is being compiled with. */
>   #ifdef CONFIG_CPU_MICROMIPS
>   #define CL_uasm_i_b(buf, off) ISAOPC(_beq)(buf, 0, 0, off)
> @@ -62,7 +70,11 @@ static struct insn insn_table[] = {
>   	{ insn_bltzl, M(bcond_op, 0, bltzl_op, 0, 0, 0), RS | BIMM },
>   	{ insn_bltz, M(bcond_op, 0, bltz_op, 0, 0, 0), RS | BIMM },
>   	{ insn_bne, M(bne_op, 0, 0, 0, 0, 0), RS | RT | BIMM },
> +#ifndef CONFIG_MIPS_R6
>   	{ insn_cache,  M(cache_op, 0, 0, 0, 0, 0),  RS | RT | SIMM },
> +#else
> +	{ insn_cache,  M6(cache_op, 0, 0, 0, 0, cache6_op),  RS | RT | SIMM9 },
> +#endif
>   	{ insn_daddiu, M(daddiu_op, 0, 0, 0, 0, 0), RS | RT | SIMM },
>   	{ insn_daddu, M(spec_op, 0, 0, 0, 0, daddu_op), RS | RT | RD },
>   	{ insn_dinsm, M(spec3_op, 0, 0, 0, 0, dinsm_op), RS | RT | RD | RE },
> @@ -85,13 +97,22 @@ static struct insn insn_table[] = {
>   	{ insn_jal,  M(jal_op, 0, 0, 0, 0, 0),	JIMM },
>   	{ insn_jalr,  M(spec_op, 0, 0, 0, 0, jalr_op), RS | RD },
>   	{ insn_j,  M(j_op, 0, 0, 0, 0, 0),  JIMM },
> +#ifndef CONFIG_CPU_MIPSR6
>   	{ insn_jr,  M(spec_op, 0, 0, 0, 0, jr_op),  RS },
> +#else
> +	{ insn_jr,  M(spec_op, 0, 0, 0, 0, jalr_op),  RS },
> +#endif
>   	{ insn_lb, M(lb_op, 0, 0, 0, 0, 0), RS | RT | SIMM },
>   	{ insn_ld,  M(ld_op, 0, 0, 0, 0, 0),  RS | RT | SIMM },
>   	{ insn_ldx, M(spec3_op, 0, 0, 0, ldx_op, lx_op), RS | RT | RD },
>   	{ insn_lh,  M(lh_op, 0, 0, 0, 0, 0),  RS | RT | SIMM },
> +#ifndef CONFIG_CPU_MIPSR6
>   	{ insn_lld,  M(lld_op, 0, 0, 0, 0, 0),	RS | RT | SIMM },
>   	{ insn_ll,  M(ll_op, 0, 0, 0, 0, 0),  RS | RT | SIMM },
> +#else
> +	{ insn_lld,  M6(spec3_op, 0, 0, 0, lld6_op),  RS | RT | SIMM9 },
> +	{ insn_ll,  M6(spec3_op, 0, 0, 0, ll6_op),  RS | RT | SIMM9 },
> +#endif
>   	{ insn_lui,  M(lui_op, 0, 0, 0, 0, 0),	RT | SIMM },
>   	{ insn_lw,  M(lw_op, 0, 0, 0, 0, 0),  RS | RT | SIMM },
>   	{ insn_lwx, M(spec3_op, 0, 0, 0, lwx_op, lx_op), RS | RT | RD },
> @@ -104,11 +125,20 @@ static struct insn insn_table[] = {
>   	{ insn_mul, M(spec2_op, 0, 0, 0, 0, mul_op), RS | RT | RD},
>   	{ insn_ori,  M(ori_op, 0, 0, 0, 0, 0),	RS | RT | UIMM },
>   	{ insn_or,  M(spec_op, 0, 0, 0, 0, or_op),  RS | RT | RD },
> +#ifndef CONFIG_CPU_MIPSR6
>   	{ insn_pref,  M(pref_op, 0, 0, 0, 0, 0),  RS | RT | SIMM },
> +#else
> +	{ insn_pref,  M6(spec3_op, 0, 0, 0, pref6_op),  RS | RT | SIMM9 },
> +#endif
>   	{ insn_rfe,  M(cop0_op, cop_op, 0, 0, 0, rfe_op),  0 },
>   	{ insn_rotr,  M(spec_op, 1, 0, 0, 0, srl_op),  RT | RD | RE },
> +#ifndef CONFIG_CPU_MIPSR6
>   	{ insn_scd,  M(scd_op, 0, 0, 0, 0, 0),	RS | RT | SIMM },
>   	{ insn_sc,  M(sc_op, 0, 0, 0, 0, 0),  RS | RT | SIMM },
> +#else
> +	{ insn_scd,  M6(spec3_op, 0, 0, 0, scd6_op),  RS | RT | SIMM9 },
> +	{ insn_sc,  M6(spec3_op, 0, 0, 0, sc6_op),  RS | RT | SIMM9 },
> +#endif
>   	{ insn_sd,  M(sd_op, 0, 0, 0, 0, 0),  RS | RT | SIMM },
>   	{ insn_sll,  M(spec_op, 0, 0, 0, 0, sll_op),  RT | RD | RE },
>   	{ insn_sllv,  M(spec_op, 0, 0, 0, 0, sllv_op),  RS | RT | RD },
> @@ -198,6 +228,8 @@ static void build_insn(u32 **buf, enum opcode opc, ...)
>   		op |= build_set(va_arg(ap, u32));
>   	if (ip->fields & SCIMM)
>   		op |= build_scimm(va_arg(ap, u32));
> +	if (ip->fields & SIMM9)
> +		op |= build_scimm9(va_arg(ap, u32));
>   	va_end(ap);
>
>   	**buf = op;
>