From: Jakub Kicinski <jakub.kicinski@netronome.com>
Date: Thu, 12 Oct 2017 10:34:12 -0700
Subject: nfp: bpf: implement byte swap instruction
Patch-mainline: v4.15-rc1
Git-commit: 3119d1fd46464c61c80731c3a9f40eee4434fc1d
References: bsc#1109837
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>
Acked-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
---
drivers/net/ethernet/netronome/nfp/bpf/jit.c | 38 +++++++++++++++++++++++++++
1 file changed, 38 insertions(+)
--- a/drivers/net/ethernet/netronome/nfp/bpf/jit.c
+++ b/drivers/net/ethernet/netronome/nfp/bpf/jit.c
@@ -746,6 +746,14 @@ wrp_cmp_reg(struct nfp_prog *nfp_prog, s
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_
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,