nfp: bpf: implement byte swap instruction

Implement byte swaps with rotations, shifts and byte loads.
Remember to clear upper parts of the 64 bit registers.

Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Simon Horman <simon.horman@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Jakub Kicinski 2017-10-12 10:34:12 -07:00 committed by David S. Miller
parent c000dfb5e2
commit 3119d1fd46

View file

@ -746,6 +746,14 @@ wrp_cmp_reg(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta,
return 0;
}
static void wrp_end32(struct nfp_prog *nfp_prog, swreg reg_in, u8 gpr_out)
{
emit_ld_field(nfp_prog, reg_both(gpr_out), 0xf, reg_in,
SHF_SC_R_ROT, 8);
emit_ld_field(nfp_prog, reg_both(gpr_out), 0x5, reg_a(gpr_out),
SHF_SC_R_ROT, 16);
}
/* --- Callbacks --- */
static int mov_reg64(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
{
@ -982,6 +990,35 @@ static int shl_imm(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
return 0;
}
static int end_reg32(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
{
const struct bpf_insn *insn = &meta->insn;
u8 gpr = insn->dst_reg * 2;
switch (insn->imm) {
case 16:
emit_ld_field(nfp_prog, reg_both(gpr), 0x9, reg_b(gpr),
SHF_SC_R_ROT, 8);
emit_ld_field(nfp_prog, reg_both(gpr), 0xe, reg_a(gpr),
SHF_SC_R_SHF, 16);
wrp_immed(nfp_prog, reg_both(gpr + 1), 0);
break;
case 32:
wrp_end32(nfp_prog, reg_a(gpr), gpr);
wrp_immed(nfp_prog, reg_both(gpr + 1), 0);
break;
case 64:
wrp_mov(nfp_prog, imm_a(nfp_prog), reg_b(gpr + 1));
wrp_end32(nfp_prog, reg_a(gpr), gpr + 1);
wrp_end32(nfp_prog, imm_a(nfp_prog), gpr);
break;
}
return 0;
}
static int imm_ld8_part2(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
{
wrp_immed(nfp_prog, reg_both(nfp_meta_prev(meta)->insn.dst_reg * 2 + 1),
@ -1297,6 +1334,7 @@ static const instr_cb_t instr_cb[256] = {
[BPF_ALU | BPF_SUB | BPF_X] = sub_reg,
[BPF_ALU | BPF_SUB | BPF_K] = sub_imm,
[BPF_ALU | BPF_LSH | BPF_K] = shl_imm,
[BPF_ALU | BPF_END | BPF_X] = end_reg32,
[BPF_LD | BPF_IMM | BPF_DW] = imm_ld8,
[BPF_LD | BPF_ABS | BPF_B] = data_ld1,
[BPF_LD | BPF_ABS | BPF_H] = data_ld2,