1 files changed, 119 insertions, 112 deletions

diff --git a/drivers/net/ethernet/netronome/nfp/bpf/jit.c b/drivers/net/ethernet/netronome/nfp/bpf/jit.c
index 29b4e5f8c102..65f0791cae0c 100644
--- a/drivers/net/ethernet/netronome/nfp/bpf/jit.c
+++ b/drivers/net/ethernet/netronome/nfp/bpf/jit.c
@@ -1214,45 +1214,83 @@ wrp_test_reg(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta,
 	return 0;
 }
 
-static int
-wrp_cmp_imm(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta,
-	    enum br_mask br_mask, bool swap)
+static const struct jmp_code_map {
+	enum br_mask br_mask;
+	bool swap;
+} jmp_code_map[] = {
+	[BPF_JGT >> 4]	= { BR_BLO, true },
+	[BPF_JGE >> 4]	= { BR_BHS, false },
+	[BPF_JLT >> 4]	= { BR_BLO, false },
+	[BPF_JLE >> 4]	= { BR_BHS, true },
+	[BPF_JSGT >> 4]	= { BR_BLT, true },
+	[BPF_JSGE >> 4]	= { BR_BGE, false },
+	[BPF_JSLT >> 4]	= { BR_BLT, false },
+	[BPF_JSLE >> 4]	= { BR_BGE, true },
+};
+
+static const struct jmp_code_map *nfp_jmp_code_get(struct nfp_insn_meta *meta)
+{
+	unsigned int op;
+
+	op = BPF_OP(meta->insn.code) >> 4;
+	/* br_mask of 0 is BR_BEQ which we don't use in jump code table */
+	if (WARN_ONCE(op >= ARRAY_SIZE(jmp_code_map) ||
+		      !jmp_code_map[op].br_mask,
+		      "no code found for jump instruction"))
+		return NULL;
+
+	return &jmp_code_map[op];
+}
+
+static int cmp_imm(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
 {
 	const struct bpf_insn *insn = &meta->insn;
 	u64 imm = insn->imm; /* sign extend */
+	const struct jmp_code_map *code;
+	enum alu_op alu_op, carry_op;
 	u8 reg = insn->dst_reg * 2;
 	swreg tmp_reg;
 
+	code = nfp_jmp_code_get(meta);
+	if (!code)
+		return -EINVAL;
+
+	alu_op = meta->jump_neg_op ? ALU_OP_ADD : ALU_OP_SUB;
+	carry_op = meta->jump_neg_op ? ALU_OP_ADD_C : ALU_OP_SUB_C;
+
 	tmp_reg = ur_load_imm_any(nfp_prog, imm & ~0U, imm_b(nfp_prog));
-	if (!swap)
-		emit_alu(nfp_prog, reg_none(), reg_a(reg), ALU_OP_SUB, tmp_reg);
+	if (!code->swap)
+		emit_alu(nfp_prog, reg_none(), reg_a(reg), alu_op, tmp_reg);
 	else
-		emit_alu(nfp_prog, reg_none(), tmp_reg, ALU_OP_SUB, reg_a(reg));
+		emit_alu(nfp_prog, reg_none(), tmp_reg, alu_op, reg_a(reg));
 
 	tmp_reg = ur_load_imm_any(nfp_prog, imm >> 32, imm_b(nfp_prog));
-	if (!swap)
+	if (!code->swap)
 		emit_alu(nfp_prog, reg_none(),
-			 reg_a(reg + 1), ALU_OP_SUB_C, tmp_reg);
+			 reg_a(reg + 1), carry_op, tmp_reg);
 	else
 		emit_alu(nfp_prog, reg_none(),
-			 tmp_reg, ALU_OP_SUB_C, reg_a(reg + 1));
+			 tmp_reg, carry_op, reg_a(reg + 1));
 
-	emit_br(nfp_prog, br_mask, insn->off, 0);
+	emit_br(nfp_prog, code->br_mask, insn->off, 0);
 
 	return 0;
 }
 
-static int
-wrp_cmp_reg(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta,
-	    enum br_mask br_mask, bool swap)
+static int cmp_reg(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
 {
 	const struct bpf_insn *insn = &meta->insn;
+	const struct jmp_code_map *code;
 	u8 areg, breg;
 
+	code = nfp_jmp_code_get(meta);
+	if (!code)
+		return -EINVAL;
+
 	areg = insn->dst_reg * 2;
 	breg = insn->src_reg * 2;
 
-	if (swap) {
+	if (code->swap) {
 		areg ^= breg;
 		breg ^= areg;
 		areg ^= breg;
@@ -1261,7 +1299,7 @@ wrp_cmp_reg(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta,
 	emit_alu(nfp_prog, reg_none(), reg_a(areg), ALU_OP_SUB, reg_b(breg));
 	emit_alu(nfp_prog, reg_none(),
 		 reg_a(areg + 1), ALU_OP_SUB_C, reg_b(breg + 1));
-	emit_br(nfp_prog, br_mask, insn->off, 0);
+	emit_br(nfp_prog, code->br_mask, insn->off, 0);
 
 	return 0;
 }
@@ -1400,7 +1438,7 @@ map_call_stack_common(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
 	if (!load_lm_ptr)
 		return 0;
 
-	emit_csr_wr(nfp_prog, stack_reg(nfp_prog),  NFP_CSR_ACT_LM_ADDR0);
+	emit_csr_wr(nfp_prog, stack_reg(nfp_prog), NFP_CSR_ACT_LM_ADDR0);
 	wrp_nops(nfp_prog, 3);
 
 	return 0;
@@ -2283,46 +2321,6 @@ static int jeq_imm(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
 	return 0;
 }
 
-static int jgt_imm(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
-{
-	return wrp_cmp_imm(nfp_prog, meta, BR_BLO, true);
-}
-
-static int jge_imm(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
-{
-	return wrp_cmp_imm(nfp_prog, meta, BR_BHS, false);
-}
-
-static int jlt_imm(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
-{
-	return wrp_cmp_imm(nfp_prog, meta, BR_BLO, false);
-}
-
-static int jle_imm(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
-{
-	return wrp_cmp_imm(nfp_prog, meta, BR_BHS, true);
-}
-
-static int jsgt_imm(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
-{
-	return wrp_cmp_imm(nfp_prog, meta, BR_BLT, true);
-}
-
-static int jsge_imm(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
-{
-	return wrp_cmp_imm(nfp_prog, meta, BR_BGE, false);
-}
-
-static int jslt_imm(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
-{
-	return wrp_cmp_imm(nfp_prog, meta, BR_BLT, false);
-}
-
-static int jsle_imm(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
-{
-	return wrp_cmp_imm(nfp_prog, meta, BR_BGE, true);
-}
-
 static int jset_imm(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
 {
 	const struct bpf_insn *insn = &meta->insn;
@@ -2392,46 +2390,6 @@ static int jeq_reg(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
 	return 0;
 }
 
-static int jgt_reg(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
-{
-	return wrp_cmp_reg(nfp_prog, meta, BR_BLO, true);
-}
-
-static int jge_reg(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
-{
-	return wrp_cmp_reg(nfp_prog, meta, BR_BHS, false);
-}
-
-static int jlt_reg(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
-{
-	return wrp_cmp_reg(nfp_prog, meta, BR_BLO, false);
-}
-
-static int jle_reg(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
-{
-	return wrp_cmp_reg(nfp_prog, meta, BR_BHS, true);
-}
-
-static int jsgt_reg(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
-{
-	return wrp_cmp_reg(nfp_prog, meta, BR_BLT, true);
-}
-
-static int jsge_reg(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
-{
-	return wrp_cmp_reg(nfp_prog, meta, BR_BGE, false);
-}
-
-static int jslt_reg(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
-{
-	return wrp_cmp_reg(nfp_prog, meta, BR_BLT, false);
-}
-
-static int jsle_reg(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
-{
-	return wrp_cmp_reg(nfp_prog, meta, BR_BGE, true);
-}
-
 static int jset_reg(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
 {
 	return wrp_test_reg(nfp_prog, meta, ALU_OP_AND, BR_BNE);
@@ -2520,25 +2478,25 @@ static const instr_cb_t instr_cb[256] = {
 	[BPF_ST | BPF_MEM | BPF_DW] =	mem_st8,
 	[BPF_JMP | BPF_JA | BPF_K] =	jump,
 	[BPF_JMP | BPF_JEQ | BPF_K] =	jeq_imm,
-	[BPF_JMP | BPF_JGT | BPF_K] =	jgt_imm,
-	[BPF_JMP | BPF_JGE | BPF_K] =	jge_imm,
-	[BPF_JMP | BPF_JLT | BPF_K] =	jlt_imm,
-	[BPF_JMP | BPF_JLE | BPF_K] =	jle_imm,
-	[BPF_JMP | BPF_JSGT | BPF_K] =  jsgt_imm,
-	[BPF_JMP | BPF_JSGE | BPF_K] =  jsge_imm,
-	[BPF_JMP | BPF_JSLT | BPF_K] =  jslt_imm,
-	[BPF_JMP | BPF_JSLE | BPF_K] =  jsle_imm,
+	[BPF_JMP | BPF_JGT | BPF_K] =	cmp_imm,
+	[BPF_JMP | BPF_JGE | BPF_K] =	cmp_imm,
+	[BPF_JMP | BPF_JLT | BPF_K] =	cmp_imm,
+	[BPF_JMP | BPF_JLE | BPF_K] =	cmp_imm,
+	[BPF_JMP | BPF_JSGT | BPF_K] =  cmp_imm,
+	[BPF_JMP | BPF_JSGE | BPF_K] =  cmp_imm,
+	[BPF_JMP | BPF_JSLT | BPF_K] =  cmp_imm,
+	[BPF_JMP | BPF_JSLE | BPF_K] =  cmp_imm,
 	[BPF_JMP | BPF_JSET | BPF_K] =	jset_imm,
 	[BPF_JMP | BPF_JNE | BPF_K] =	jne_imm,
 	[BPF_JMP | BPF_JEQ | BPF_X] =	jeq_reg,
-	[BPF_JMP | BPF_JGT | BPF_X] =	jgt_reg,
-	[BPF_JMP | BPF_JGE | BPF_X] =	jge_reg,
-	[BPF_JMP | BPF_JLT | BPF_X] =	jlt_reg,
-	[BPF_JMP | BPF_JLE | BPF_X] =	jle_reg,
-	[BPF_JMP | BPF_JSGT | BPF_X] =  jsgt_reg,
-	[BPF_JMP | BPF_JSGE | BPF_X] =  jsge_reg,
-	[BPF_JMP | BPF_JSLT | BPF_X] =  jslt_reg,
-	[BPF_JMP | BPF_JSLE | BPF_X] =  jsle_reg,
+	[BPF_JMP | BPF_JGT | BPF_X] =	cmp_reg,
+	[BPF_JMP | BPF_JGE | BPF_X] =	cmp_reg,
+	[BPF_JMP | BPF_JLT | BPF_X] =	cmp_reg,
+	[BPF_JMP | BPF_JLE | BPF_X] =	cmp_reg,
+	[BPF_JMP | BPF_JSGT | BPF_X] =  cmp_reg,
+	[BPF_JMP | BPF_JSGE | BPF_X] =  cmp_reg,
+	[BPF_JMP | BPF_JSLT | BPF_X] =  cmp_reg,
+	[BPF_JMP | BPF_JSLE | BPF_X] =  cmp_reg,
 	[BPF_JMP | BPF_JSET | BPF_X] =	jset_reg,
 	[BPF_JMP | BPF_JNE | BPF_X] =	jne_reg,
 	[BPF_JMP | BPF_CALL] =		call,
@@ -2777,6 +2735,54 @@ static void nfp_bpf_opt_reg_init(struct nfp_prog *nfp_prog)
 	}
 }
 
+/* abs(insn.imm) will fit better into unrestricted reg immediate -
+ * convert add/sub of a negative number into a sub/add of a positive one.
+ */
+static void nfp_bpf_opt_neg_add_sub(struct nfp_prog *nfp_prog)
+{
+	struct nfp_insn_meta *meta;
+
+	list_for_each_entry(meta, &nfp_prog->insns, l) {
+		struct bpf_insn insn = meta->insn;
+
+		if (meta->skip)
+			continue;
+
+		if (BPF_CLASS(insn.code) != BPF_ALU &&
+		    BPF_CLASS(insn.code) != BPF_ALU64 &&
+		    BPF_CLASS(insn.code) != BPF_JMP)
+			continue;
+		if (BPF_SRC(insn.code) != BPF_K)
+			continue;
+		if (insn.imm >= 0)
+			continue;
+
+		if (BPF_CLASS(insn.code) == BPF_JMP) {
+			switch (BPF_OP(insn.code)) {
+			case BPF_JGE:
+			case BPF_JSGE:
+			case BPF_JLT:
+			case BPF_JSLT:
+				meta->jump_neg_op = true;
+				break;
+			default:
+				continue;
+			}
+		} else {
+			if (BPF_OP(insn.code) == BPF_ADD)
+				insn.code = BPF_CLASS(insn.code) | BPF_SUB;
+			else if (BPF_OP(insn.code) == BPF_SUB)
+				insn.code = BPF_CLASS(insn.code) | BPF_ADD;
+			else
+				continue;
+
+			meta->insn.code = insn.code | BPF_K;
+		}
+
+		meta->insn.imm = -insn.imm;
+	}
+}
+
 /* Remove masking after load since our load guarantees this is not needed */
 static void nfp_bpf_opt_ld_mask(struct nfp_prog *nfp_prog)
 {
@@ -3212,6 +3218,7 @@ static int nfp_bpf_optimize(struct nfp_prog *nfp_prog)
 {
 	nfp_bpf_opt_reg_init(nfp_prog);
 
+	nfp_bpf_opt_neg_add_sub(nfp_prog);
 	nfp_bpf_opt_ld_mask(nfp_prog);
 	nfp_bpf_opt_ld_shift(nfp_prog);
 	nfp_bpf_opt_ldst_gather(nfp_prog);