This includes:
- CSRRD
- CSRWR
- CSRXCHG
Signed-off-by: Xiaojuan Yang <yangxiaojuan@loongson.cn>
Signed-off-by: Song Gao <gaosong@loongson.cn>
---
target/loongarch/cpu.h | 88 +++++++++++++
target/loongarch/csr_helper.c | 112 +++++++++++++++++
target/loongarch/disas.c | 15 +++
target/loongarch/helper.h | 7 ++
target/loongarch/insn_trans/trans_core.c.inc | 123 +++++++++++++++++++
target/loongarch/insns.decode | 13 ++
target/loongarch/meson.build | 1 +
target/loongarch/translate.c | 5 +
8 files changed, 364 insertions(+)
create mode 100644 target/loongarch/csr_helper.c
create mode 100644 target/loongarch/insn_trans/trans_core.c.inc
diff --git a/target/loongarch/cpu.h b/target/loongarch/cpu.h
index 232d51e788..2a1841a708 100644
--- a/target/loongarch/cpu.h
+++ b/target/loongarch/cpu.h
@@ -260,6 +260,94 @@ struct CPULoongArchState {
#endif
};
+#define CSR_OFF(X) \
+ [LOONGARCH_CSR_##X] = offsetof(CPULoongArchState, CSR_##X)
+#define CSR_OFF_ARRAY(X, N) \
+ [LOONGARCH_CSR_##X(N)] = offsetof(CPULoongArchState, CSR_##X[N])
+
+static const int csr_offsets[] = {
+ CSR_OFF(CRMD),
+ CSR_OFF(PRMD),
+ CSR_OFF(EUEN),
+ CSR_OFF(MISC),
+ CSR_OFF(ECFG),
+ CSR_OFF(ESTAT),
+ CSR_OFF(ERA),
+ CSR_OFF(BADV),
+ CSR_OFF(BADI),
+ CSR_OFF(EENTRY),
+ CSR_OFF(TLBIDX),
+ CSR_OFF(TLBEHI),
+ CSR_OFF(TLBELO0),
+ CSR_OFF(TLBELO1),
+ CSR_OFF(ASID),
+ CSR_OFF(PGDL),
+ CSR_OFF(PGDH),
+ CSR_OFF(PGD),
+ CSR_OFF(PWCL),
+ CSR_OFF(PWCH),
+ CSR_OFF(STLBPS),
+ CSR_OFF(RVACFG),
+ CSR_OFF(CPUID),
+ CSR_OFF(PRCFG1),
+ CSR_OFF(PRCFG2),
+ CSR_OFF(PRCFG3),
+ CSR_OFF_ARRAY(SAVE, 0),
+ CSR_OFF_ARRAY(SAVE, 1),
+ CSR_OFF_ARRAY(SAVE, 2),
+ CSR_OFF_ARRAY(SAVE, 3),
+ CSR_OFF_ARRAY(SAVE, 4),
+ CSR_OFF_ARRAY(SAVE, 5),
+ CSR_OFF_ARRAY(SAVE, 6),
+ CSR_OFF_ARRAY(SAVE, 7),
+ CSR_OFF_ARRAY(SAVE, 8),
+ CSR_OFF_ARRAY(SAVE, 9),
+ CSR_OFF_ARRAY(SAVE, 10),
+ CSR_OFF_ARRAY(SAVE, 11),
+ CSR_OFF_ARRAY(SAVE, 12),
+ CSR_OFF_ARRAY(SAVE, 13),
+ CSR_OFF_ARRAY(SAVE, 14),
+ CSR_OFF_ARRAY(SAVE, 15),
+ CSR_OFF(TID),
+ CSR_OFF(TCFG),
+ CSR_OFF(TVAL),
+ CSR_OFF(CNTC),
+ CSR_OFF(TICLR),
+ CSR_OFF(LLBCTL),
+ CSR_OFF(IMPCTL1),
+ CSR_OFF(IMPCTL2),
+ CSR_OFF(TLBRENTRY),
+ CSR_OFF(TLBRBADV),
+ CSR_OFF(TLBRERA),
+ CSR_OFF(TLBRSAVE),
+ CSR_OFF(TLBRELO0),
+ CSR_OFF(TLBRELO1),
+ CSR_OFF(TLBREHI),
+ CSR_OFF(TLBRPRMD),
+ CSR_OFF(MERRCTL),
+ CSR_OFF(MERRINFO1),
+ CSR_OFF(MERRINFO2),
+ CSR_OFF(MERRENTRY),
+ CSR_OFF(MERRERA),
+ CSR_OFF(MERRSAVE),
+ CSR_OFF(CTAG),
+ CSR_OFF_ARRAY(DMW, 0),
+ CSR_OFF_ARRAY(DMW, 1),
+ CSR_OFF_ARRAY(DMW, 2),
+ CSR_OFF_ARRAY(DMW, 3),
+ CSR_OFF(DBG),
+ CSR_OFF(DERA),
+ CSR_OFF(DSAVE),
+};
+
+static inline int cpu_csr_offset(unsigned csr_num)
+{
+ if (csr_num < ARRAY_SIZE(csr_offsets)) {
+ return csr_offsets[csr_num];
+ }
+ return 0;
+}
+
/**
* LoongArchCPU:
* @env: #CPULoongArchState
diff --git a/target/loongarch/csr_helper.c b/target/loongarch/csr_helper.c
new file mode 100644
index 0000000000..4d0619cec8
--- /dev/null
+++ b/target/loongarch/csr_helper.c
@@ -0,0 +1,112 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ * LoongArch emulation helpers for csr registers
+ *
+ * Copyright (c) 2021 Loongson Technology Corporation Limited
+ */
+
+#include "qemu/osdep.h"
+#include "qemu/main-loop.h"
+#include "cpu.h"
+#include "internals.h"
+#include "qemu/host-utils.h"
+#include "exec/helper-proto.h"
+#include "exec/exec-all.h"
+#include "exec/cpu_ldst.h"
+#include "hw/irq.h"
+#include "cpu-csr.h"
+#include "hw/loongarch/loongarch.h"
+#include "tcg/tcg-ldst.h"
+
+target_ulong helper_csr_rdq(CPULoongArchState *env, uint64_t csr)
+{
+ LoongArchCPU *cpu;
+ int64_t v;
+
+ switch (csr) {
+ case LOONGARCH_CSR_PGD:
+ if (env->CSR_TLBRERA & 0x1) {
+ v = env->CSR_TLBRBADV;
+ } else {
+ v = env->CSR_BADV;
+ }
+
+ if ((v >> 63) & 0x1) {
+ v = env->CSR_PGDH;
+ } else {
+ v = env->CSR_PGDL;
+ }
+ break;
+ case LOONGARCH_CSR_CPUID:
+ v = (env_cpu(env))->cpu_index;
+ break;
+ case LOONGARCH_CSR_TVAL:
+ cpu = LOONGARCH_CPU(env_cpu(env));
+ v = cpu_loongarch_get_constant_timer_ticks(cpu);
+ break;
+ default:
+ break;
+ }
+
+ return v;
+}
+
+target_ulong helper_csr_wrq(CPULoongArchState *env, target_ulong val,
+ uint64_t csr)
+{
+ LoongArchCPU *cpu;
+ int64_t old_v = -1;
+
+ switch (csr) {
+ case LOONGARCH_CSR_ESTAT:
+ /* Only IS[1:0] can be write */
+ env->CSR_ESTAT = FIELD_DP64(env->CSR_ESTAT, CSR_ESTAT, IS, val & 0x3);
+ break;
+ case LOONGARCH_CSR_ASID:
+ old_v = env->CSR_ASID;
+ /* Only ASID filed of CSR_ASID can be write. */
+ env->CSR_ASID = FIELD_DP64(env->CSR_ASID, CSR_ASID, ASID,
+ val & R_CSR_ASID_ASID_MASK);
+ if (old_v != val) {
+ tlb_flush(env_cpu(env));
+ }
+ break;
+ case LOONGARCH_CSR_TCFG:
+ cpu = LOONGARCH_CPU(env_cpu(env));
+ old_v = env->CSR_TCFG;
+ cpu_loongarch_store_constant_timer_config(cpu, val);
+ break;
+ case LOONGARCH_CSR_TICLR:
+ old_v = 0;
+ env->CSR_ESTAT &= ~(1 << IRQ_TIMER);
+ cpu_reset_interrupt(env_cpu(env), CPU_INTERRUPT_HARD);
+ break;
+ default:
+ break;
+ }
+
+ return old_v;
+}
+
+target_ulong helper_csr_xchgq(CPULoongArchState *env, target_ulong new_val,
+ target_ulong mask, uint64_t csr_num)
+{
+ unsigned csr_offset = cpu_csr_offset(csr_num);
+ if (csr_offset == 0) {
+ /* CSR is undefined: read as 0, write ignored. */
+ return 0;
+ }
+
+ uint64_t *csr = (void *)env + csr_offset;
+ uint64_t old_val = *csr;
+
+ new_val = (new_val & mask) | (old_val & ~mask);
+
+ if (csr_num == LOONGARCH_CSR_TCFG) {
+ LoongArchCPU *cpu = LOONGARCH_CPU(env_cpu(env));
+ cpu_loongarch_store_constant_timer_config(cpu, new_val);
+ } else {
+ *csr = new_val;
+ }
+ return old_val;
+}
diff --git a/target/loongarch/disas.c b/target/loongarch/disas.c
index 45be34de27..de683bb88b 100644
--- a/target/loongarch/disas.c
+++ b/target/loongarch/disas.c
@@ -204,6 +204,18 @@ static void output_rr_offs(DisasContext *ctx, arg_rr_offs *a,
output(ctx, mnemonic, "r%d, r%d, %d", a->rj, a->rd, a->offs);
}
+static void output_r_csr(DisasContext *ctx, arg_r_csr *a,
+ const char *mnemonic)
+{
+ output(ctx, mnemonic, "r%d, %d", a->rd, a->csr);
+}
+
+static void output_rr_csr(DisasContext *ctx, arg_rr_csr *a,
+ const char *mnemonic)
+{
+ output(ctx, mnemonic, "r%d, r%d, %d", a->rd, a->rj, a->csr);
+}
+
#define INSN(insn, type) \
static bool trans_##insn(DisasContext *ctx, arg_##type * a) \
{ \
@@ -516,6 +528,9 @@ INSN(blt, rr_offs)
INSN(bge, rr_offs)
INSN(bltu, rr_offs)
INSN(bgeu, rr_offs)
+INSN(csrrd, r_csr)
+INSN(csrwr, r_csr)
+INSN(csrxchg, rr_csr)
#define output_fcmp(C, PREFIX, SUFFIX) \
{ \
diff --git a/target/loongarch/helper.h b/target/loongarch/helper.h
index da1a2bced7..036dbf31f8 100644
--- a/target/loongarch/helper.h
+++ b/target/loongarch/helper.h
@@ -92,3 +92,10 @@ DEF_HELPER_2(frint_s, i64, env, i64)
DEF_HELPER_2(frint_d, i64, env, i64)
DEF_HELPER_FLAGS_2(set_rounding_mode, TCG_CALL_NO_RWG, void, env, i32)
+
+/*Core functions */
+#ifndef CONFIG_USER_ONLY
+DEF_HELPER_2(csr_rdq, i64, env, i64)
+DEF_HELPER_3(csr_wrq, i64, env, tl, i64)
+DEF_HELPER_4(csr_xchgq, i64, env, tl, tl, i64)
+#endif /* !CONFIG_USER_ONLY */
diff --git a/target/loongarch/insn_trans/trans_core.c.inc b/target/loongarch/insn_trans/trans_core.c.inc
new file mode 100644
index 0000000000..7d2cfe3534
--- /dev/null
+++ b/target/loongarch/insn_trans/trans_core.c.inc
@@ -0,0 +1,123 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ * LoongArch translate functions for system mode
+ *
+ * Copyright (c) 2021 Loongson Technology Corporation Limited
+ */
+
+/* Privileged instruction translation */
+
+#include "cpu-csr.h"
+
+#ifdef CONFIG_USER_ONLY
+
+#define GEN_FALSE_TRANS(name) \
+static bool trans_##name(DisasContext *ctx, arg_##name * a) \
+{ \
+ return false; \
+}
+
+GEN_FALSE_TRANS(csrrd)
+GEN_FALSE_TRANS(csrwr)
+GEN_FALSE_TRANS(csrxchg)
+
+#else
+
+static bool check_plv(DisasContext *ctx)
+{
+ if (ctx->base.tb->flags == MMU_USER_IDX) {
+ generate_exception(ctx, EXCCODE_IPE);
+ return true;
+ }
+ return false;
+}
+
+static bool ro_csr(int csr_num)
+{
+ /*
+ * For now qemu does not support any features of the MISC
+ * bits yet treat as a RO CSR.
+ */
+ if ((csr_num == LOONGARCH_CSR_BADI) || (csr_num == LOONGARCH_CSR_CPUID) ||
+ (csr_num == LOONGARCH_CSR_PRCFG1) || (csr_num == LOONGARCH_CSR_PRCFG2) ||
+ (csr_num == LOONGARCH_CSR_PRCFG3) || (csr_num == LOONGARCH_CSR_PGD) ||
+ (csr_num == LOONGARCH_CSR_TVAL) || (csr_num == LOONGARCH_CSR_MISC)) {
+ return true;
+ }
+
+ return false;
+}
+
+static bool trans_csrrd(DisasContext *ctx, arg_csrrd *a)
+{
+ TCGv dest = gpr_dst(ctx, a->rd, EXT_NONE);
+
+ if (check_plv(ctx)) {
+ return false;
+ }
+
+ unsigned csr_offset = cpu_csr_offset(a->csr);
+ if (csr_offset == 0) {
+ /* CSR is undefined: read as 0 */
+ dest = tcg_constant_tl(0);
+ return true;
+ }
+
+ if ((a->csr == LOONGARCH_CSR_PGD) || (a->csr == LOONGARCH_CSR_CPUID) ||
+ (a->csr == LOONGARCH_CSR_TVAL)) {
+ gen_helper_csr_rdq(dest, cpu_env, tcg_constant_i64(a->csr));
+ } else {
+ tcg_gen_ld_tl(dest, cpu_env, csr_offset);
+ }
+ return true;
+}
+
+static bool trans_csrwr(DisasContext *ctx, arg_csrwr *a)
+{
+ TCGv dest = gpr_dst(ctx, a->rd, EXT_NONE);
+ TCGv src1 = gpr_src(ctx, a->rd, EXT_NONE);
+
+ if (check_plv(ctx) || ro_csr(a->csr)) {
+ return false;
+ }
+
+ unsigned csr_offset = cpu_csr_offset(a->csr);
+ if (csr_offset == 0) {
+ /* CSR is undefined: write ignored. */
+ return true;
+ }
+
+ if ((a->csr == LOONGARCH_CSR_ASID) || (a->csr == LOONGARCH_CSR_TCFG) ||
+ (a->csr == LOONGARCH_CSR_TICLR) || (a->csr == LOONGARCH_CSR_ESTAT)) {
+ gen_helper_csr_wrq(dest, cpu_env, src1, tcg_constant_i64(a->csr));
+ } else {
+ TCGv temp = tcg_temp_new();
+ tcg_gen_ld_tl(temp, cpu_env, csr_offset);
+ tcg_gen_st_tl(src1, cpu_env, csr_offset);
+ tcg_gen_mov_tl(dest, temp);
+ tcg_temp_free(temp);
+
+ /* Cpu state may be changed, need exit */
+ if ((a->csr == LOONGARCH_CSR_CRMD) || (a->csr == LOONGARCH_CSR_EUEN)) {
+ tcg_gen_movi_tl(cpu_pc, ctx->base.pc_next + 4);
+ ctx->base.is_jmp = DISAS_EXIT;
+ }
+ }
+
+ return true;
+}
+
+static bool trans_csrxchg(DisasContext *ctx, arg_csrxchg *a)
+{
+ TCGv dest = gpr_dst(ctx, a->rd, EXT_NONE);
+ TCGv src1 = gpr_src(ctx, a->rd, EXT_NONE);
+ TCGv src2 = gpr_src(ctx, a->rj, EXT_NONE);
+
+ if (check_plv(ctx) || ro_csr(a->csr)) {
+ return false;
+ }
+ gen_helper_csr_xchgq(dest, cpu_env, src1, src2, tcg_constant_i64(a->csr));
+ return true;
+}
+
+#endif
diff --git a/target/loongarch/insns.decode b/target/loongarch/insns.decode
index 3379d22979..647fcb9def 100644
--- a/target/loongarch/insns.decode
+++ b/target/loongarch/insns.decode
@@ -45,6 +45,8 @@
&c_offs cj offs
&offs offs
&rr_offs rj rd offs
+&r_csr rd csr
+&rr_csr rd rj csr
#
# Formats
@@ -85,6 +87,8 @@
@c_offs21 .... .. ................ .. cj:3 ..... &c_offs offs=%offs21
@offs26 .... .. .......................... &offs offs=%offs26
@rr_offs16 .... .. ................ rj:5 rd:5 &rr_offs offs=%offs16
+@r_csr .... .... csr:14 ..... rd:5 &r_csr
+@rr_csr .... .... csr:14 rj:5 rd:5 &rr_csr
#
# Fixed point arithmetic operation instruction
@@ -440,3 +444,12 @@ blt 0110 00 ................ ..... ..... @rr_offs16
bge 0110 01 ................ ..... ..... @rr_offs16
bltu 0110 10 ................ ..... ..... @rr_offs16
bgeu 0110 11 ................ ..... ..... @rr_offs16
+
+#
+# Core instructions
+#
+{
+ csrrd 0000 0100 .............. 00000 ..... @r_csr
+ csrwr 0000 0100 .............. 00001 ..... @r_csr
+ csrxchg 0000 0100 .............. ..... ..... @rr_csr
+}
diff --git a/target/loongarch/meson.build b/target/loongarch/meson.build
index 6bf2d88104..5fb7542e88 100644
--- a/target/loongarch/meson.build
+++ b/target/loongarch/meson.build
@@ -19,6 +19,7 @@ loongarch_softmmu_ss.add(files(
'machine.c',
'constant_timer.c',
'tlb_helper.c',
+ 'csr_helper.c',
))
loongarch_ss.add_all(when: 'CONFIG_TCG', if_true: [loongarch_tcg_ss])
diff --git a/target/loongarch/translate.c b/target/loongarch/translate.c
index 2710764653..09771ee43f 100644
--- a/target/loongarch/translate.c
+++ b/target/loongarch/translate.c
@@ -26,6 +26,7 @@ TCGv_i32 cpu_fcsr0;
TCGv_i64 cpu_fpr[32];
#define DISAS_STOP DISAS_TARGET_0
+#define DISAS_EXIT DISAS_TARGET_1
static inline int plus_1(DisasContext *ctx, int x)
{
@@ -172,6 +173,7 @@ static void gen_set_gpr(int reg_num, TCGv t, DisasExtend dst_ext)
#include "insn_trans/trans_fmov.c.inc"
#include "insn_trans/trans_fmemory.c.inc"
#include "insn_trans/trans_branch.c.inc"
+#include "insn_trans/trans_core.c.inc"
static void loongarch_tr_translate_insn(DisasContextBase *dcbase, CPUState *cs)
{
@@ -209,6 +211,9 @@ static void loongarch_tr_tb_stop(DisasContextBase *dcbase, CPUState *cs)
break;
case DISAS_NORETURN:
break;
+ case DISAS_EXIT:
+ tcg_gen_exit_tb(NULL, 0);
+ break;
default:
g_assert_not_reached();
}
--
2.27.0
On 1/8/22 17:13, Xiaojuan Yang wrote:
> This includes:
> - CSRRD
> - CSRWR
> - CSRXCHG
>
> Signed-off-by: Xiaojuan Yang<yangxiaojuan@loongson.cn>
> Signed-off-by: Song Gao<gaosong@loongson.cn>
> ---
> target/loongarch/cpu.h | 88 +++++++++++++
> target/loongarch/csr_helper.c | 112 +++++++++++++++++
> target/loongarch/disas.c | 15 +++
> target/loongarch/helper.h | 7 ++
> target/loongarch/insn_trans/trans_core.c.inc | 123 +++++++++++++++++++
> target/loongarch/insns.decode | 13 ++
> target/loongarch/meson.build | 1 +
> target/loongarch/translate.c | 5 +
> 8 files changed, 364 insertions(+)
> create mode 100644 target/loongarch/csr_helper.c
> create mode 100644 target/loongarch/insn_trans/trans_core.c.inc
>
> diff --git a/target/loongarch/cpu.h b/target/loongarch/cpu.h
> index 232d51e788..2a1841a708 100644
> --- a/target/loongarch/cpu.h
> +++ b/target/loongarch/cpu.h
> @@ -260,6 +260,94 @@ struct CPULoongArchState {
> #endif
> };
>
> +#define CSR_OFF(X) \
> + [LOONGARCH_CSR_##X] = offsetof(CPULoongArchState, CSR_##X)
> +#define CSR_OFF_ARRAY(X, N) \
> + [LOONGARCH_CSR_##X(N)] = offsetof(CPULoongArchState, CSR_##X[N])
> +
> +static const int csr_offsets[] = {
> + CSR_OFF(CRMD),
> + CSR_OFF(PRMD),
> + CSR_OFF(EUEN),
> + CSR_OFF(MISC),
> + CSR_OFF(ECFG),
> + CSR_OFF(ESTAT),
> + CSR_OFF(ERA),
> + CSR_OFF(BADV),
> + CSR_OFF(BADI),
> + CSR_OFF(EENTRY),
> + CSR_OFF(TLBIDX),
> + CSR_OFF(TLBEHI),
> + CSR_OFF(TLBELO0),
> + CSR_OFF(TLBELO1),
> + CSR_OFF(ASID),
> + CSR_OFF(PGDL),
> + CSR_OFF(PGDH),
> + CSR_OFF(PGD),
> + CSR_OFF(PWCL),
> + CSR_OFF(PWCH),
> + CSR_OFF(STLBPS),
> + CSR_OFF(RVACFG),
> + CSR_OFF(CPUID),
> + CSR_OFF(PRCFG1),
> + CSR_OFF(PRCFG2),
> + CSR_OFF(PRCFG3),
> + CSR_OFF_ARRAY(SAVE, 0),
> + CSR_OFF_ARRAY(SAVE, 1),
> + CSR_OFF_ARRAY(SAVE, 2),
> + CSR_OFF_ARRAY(SAVE, 3),
> + CSR_OFF_ARRAY(SAVE, 4),
> + CSR_OFF_ARRAY(SAVE, 5),
> + CSR_OFF_ARRAY(SAVE, 6),
> + CSR_OFF_ARRAY(SAVE, 7),
> + CSR_OFF_ARRAY(SAVE, 8),
> + CSR_OFF_ARRAY(SAVE, 9),
> + CSR_OFF_ARRAY(SAVE, 10),
> + CSR_OFF_ARRAY(SAVE, 11),
> + CSR_OFF_ARRAY(SAVE, 12),
> + CSR_OFF_ARRAY(SAVE, 13),
> + CSR_OFF_ARRAY(SAVE, 14),
> + CSR_OFF_ARRAY(SAVE, 15),
> + CSR_OFF(TID),
> + CSR_OFF(TCFG),
> + CSR_OFF(TVAL),
> + CSR_OFF(CNTC),
> + CSR_OFF(TICLR),
> + CSR_OFF(LLBCTL),
> + CSR_OFF(IMPCTL1),
> + CSR_OFF(IMPCTL2),
> + CSR_OFF(TLBRENTRY),
> + CSR_OFF(TLBRBADV),
> + CSR_OFF(TLBRERA),
> + CSR_OFF(TLBRSAVE),
> + CSR_OFF(TLBRELO0),
> + CSR_OFF(TLBRELO1),
> + CSR_OFF(TLBREHI),
> + CSR_OFF(TLBRPRMD),
> + CSR_OFF(MERRCTL),
> + CSR_OFF(MERRINFO1),
> + CSR_OFF(MERRINFO2),
> + CSR_OFF(MERRENTRY),
> + CSR_OFF(MERRERA),
> + CSR_OFF(MERRSAVE),
> + CSR_OFF(CTAG),
> + CSR_OFF_ARRAY(DMW, 0),
> + CSR_OFF_ARRAY(DMW, 1),
> + CSR_OFF_ARRAY(DMW, 2),
> + CSR_OFF_ARRAY(DMW, 3),
> + CSR_OFF(DBG),
> + CSR_OFF(DERA),
> + CSR_OFF(DSAVE),
> +};
> +
> +static inline int cpu_csr_offset(unsigned csr_num)
> +{
> + if (csr_num < ARRAY_SIZE(csr_offsets)) {
> + return csr_offsets[csr_num];
> + }
> + return 0;
> +}
> +
> /**
> * LoongArchCPU:
> * @env: #CPULoongArchState
> diff --git a/target/loongarch/csr_helper.c b/target/loongarch/csr_helper.c
> new file mode 100644
> index 0000000000..4d0619cec8
> --- /dev/null
> +++ b/target/loongarch/csr_helper.c
> @@ -0,0 +1,112 @@
> +/* SPDX-License-Identifier: GPL-2.0-or-later */
> +/*
> + * LoongArch emulation helpers for csr registers
"Emulation helpers for CSRs" is enough.
> + *
> + * Copyright (c) 2021 Loongson Technology Corporation Limited
> + */
> +
> +#include "qemu/osdep.h"
> +#include "qemu/main-loop.h"
> +#include "cpu.h"
> +#include "internals.h"
> +#include "qemu/host-utils.h"
> +#include "exec/helper-proto.h"
> +#include "exec/exec-all.h"
> +#include "exec/cpu_ldst.h"
> +#include "hw/irq.h"
> +#include "cpu-csr.h"
> +#include "hw/loongarch/loongarch.h"
> +#include "tcg/tcg-ldst.h"
> +
> +target_ulong helper_csr_rdq(CPULoongArchState *env, uint64_t csr)
> +{
> + LoongArchCPU *cpu;
> + int64_t v;
> +
> + switch (csr) {
> + case LOONGARCH_CSR_PGD:
> + if (env->CSR_TLBRERA & 0x1) {
> + v = env->CSR_TLBRBADV;
> + } else {
> + v = env->CSR_BADV;
> + }
> +
> + if ((v >> 63) & 0x1) {
> + v = env->CSR_PGDH;
> + } else {
> + v = env->CSR_PGDL;
> + }
> + break;
> + case LOONGARCH_CSR_CPUID:
> + v = (env_cpu(env))->cpu_index;
> + break;
> + case LOONGARCH_CSR_TVAL:
> + cpu = LOONGARCH_CPU(env_cpu(env));
> + v = cpu_loongarch_get_constant_timer_ticks(cpu);
> + break;
> + default:
> + break;
> + }
> +
> + return v;
> +}
> +
> +target_ulong helper_csr_wrq(CPULoongArchState *env, target_ulong val,
> + uint64_t csr)
> +{
> + LoongArchCPU *cpu;
> + int64_t old_v = -1;
> +
> + switch (csr) {
> + case LOONGARCH_CSR_ESTAT:
> + /* Only IS[1:0] can be write */
> + env->CSR_ESTAT = FIELD_DP64(env->CSR_ESTAT, CSR_ESTAT, IS, val & 0x3);
> + break;
> + case LOONGARCH_CSR_ASID:
> + old_v = env->CSR_ASID;
> + /* Only ASID filed of CSR_ASID can be write. */
> + env->CSR_ASID = FIELD_DP64(env->CSR_ASID, CSR_ASID, ASID,
> + val & R_CSR_ASID_ASID_MASK);
> + if (old_v != val) {
> + tlb_flush(env_cpu(env));
> + }
> + break;
> + case LOONGARCH_CSR_TCFG:
> + cpu = LOONGARCH_CPU(env_cpu(env));
> + old_v = env->CSR_TCFG;
> + cpu_loongarch_store_constant_timer_config(cpu, val);
> + break;
> + case LOONGARCH_CSR_TICLR:
> + old_v = 0;
> + env->CSR_ESTAT &= ~(1 << IRQ_TIMER);
> + cpu_reset_interrupt(env_cpu(env), CPU_INTERRUPT_HARD);
> + break;
> + default:
> + break;
> + }
> +
> + return old_v;
> +}
> +
> +target_ulong helper_csr_xchgq(CPULoongArchState *env, target_ulong new_val,
> + target_ulong mask, uint64_t csr_num)
> +{
> + unsigned csr_offset = cpu_csr_offset(csr_num);
> + if (csr_offset == 0) {
> + /* CSR is undefined: read as 0, write ignored. */
"Undefined CSR; reads return 0, writes are ignored. */
> + return 0;
> + }
> +
> + uint64_t *csr = (void *)env + csr_offset;
> + uint64_t old_val = *csr;
> +
> + new_val = (new_val & mask) | (old_val & ~mask);
> +
> + if (csr_num == LOONGARCH_CSR_TCFG) {
> + LoongArchCPU *cpu = LOONGARCH_CPU(env_cpu(env));
> + cpu_loongarch_store_constant_timer_config(cpu, new_val);
> + } else {
> + *csr = new_val;
> + }
> + return old_val;
> +}
> diff --git a/target/loongarch/disas.c b/target/loongarch/disas.c
> index 45be34de27..de683bb88b 100644
> --- a/target/loongarch/disas.c
> +++ b/target/loongarch/disas.c
> @@ -204,6 +204,18 @@ static void output_rr_offs(DisasContext *ctx, arg_rr_offs *a,
> output(ctx, mnemonic, "r%d, r%d, %d", a->rj, a->rd, a->offs);
> }
>
> +static void output_r_csr(DisasContext *ctx, arg_r_csr *a,
> + const char *mnemonic)
> +{
> + output(ctx, mnemonic, "r%d, %d", a->rd, a->csr);
> +}
> +
> +static void output_rr_csr(DisasContext *ctx, arg_rr_csr *a,
> + const char *mnemonic)
> +{
> + output(ctx, mnemonic, "r%d, r%d, %d", a->rd, a->rj, a->csr);
> +}
> +
> #define INSN(insn, type) \
> static bool trans_##insn(DisasContext *ctx, arg_##type * a) \
> { \
> @@ -516,6 +528,9 @@ INSN(blt, rr_offs)
> INSN(bge, rr_offs)
> INSN(bltu, rr_offs)
> INSN(bgeu, rr_offs)
> +INSN(csrrd, r_csr)
> +INSN(csrwr, r_csr)
> +INSN(csrxchg, rr_csr)
>
> #define output_fcmp(C, PREFIX, SUFFIX) \
> { \
> diff --git a/target/loongarch/helper.h b/target/loongarch/helper.h
> index da1a2bced7..036dbf31f8 100644
> --- a/target/loongarch/helper.h
> +++ b/target/loongarch/helper.h
> @@ -92,3 +92,10 @@ DEF_HELPER_2(frint_s, i64, env, i64)
> DEF_HELPER_2(frint_d, i64, env, i64)
>
> DEF_HELPER_FLAGS_2(set_rounding_mode, TCG_CALL_NO_RWG, void, env, i32)
> +
> +/*Core functions */
> +#ifndef CONFIG_USER_ONLY
> +DEF_HELPER_2(csr_rdq, i64, env, i64)
> +DEF_HELPER_3(csr_wrq, i64, env, tl, i64)
> +DEF_HELPER_4(csr_xchgq, i64, env, tl, tl, i64)
> +#endif /* !CONFIG_USER_ONLY */
> diff --git a/target/loongarch/insn_trans/trans_core.c.inc b/target/loongarch/insn_trans/trans_core.c.inc
> new file mode 100644
> index 0000000000..7d2cfe3534
> --- /dev/null
> +++ b/target/loongarch/insn_trans/trans_core.c.inc
> @@ -0,0 +1,123 @@
> +/* SPDX-License-Identifier: GPL-2.0-or-later */
> +/*
> + * LoongArch translate functions for system mode
"Translation functions for privileged mode"? And rename the file to
"trans_privileged.c.inc"?
> + *
> + * Copyright (c) 2021 Loongson Technology Corporation Limited
> + */
> +
> +/* Privileged instruction translation */
And this comment could be removed.
> +
> +#include "cpu-csr.h"
> +
> +#ifdef CONFIG_USER_ONLY
> +
> +#define GEN_FALSE_TRANS(name) \
GEN_TRANS_STUB? "false trans" sounds like something that's NOT a
"trans", but the generated functions are actually real "trans" helpers
that do nothing.
> +static bool trans_##name(DisasContext *ctx, arg_##name * a) \
> +{ \
> + return false; \
> +}
> +
> +GEN_FALSE_TRANS(csrrd)
> +GEN_FALSE_TRANS(csrwr)
> +GEN_FALSE_TRANS(csrxchg)
> +
> +#else
> +
> +static bool check_plv(DisasContext *ctx)
> +{
> + if (ctx->base.tb->flags == MMU_USER_IDX) {
> + generate_exception(ctx, EXCCODE_IPE);
Are the instructions accessible from PLV0 to PLV2 inclusive, as implied
by this "if" statement? Or do we only allow for PLV0?
> + return true;
> + }
> + return false;
> +}
> +
> +static bool ro_csr(int csr_num)
> +{
> + /*
> + * For now qemu does not support any features of the MISC
> + * bits yet treat as a RO CSR.
"Treat MISC as a read-only CSR because its features are not supported yet."
> + */
> + if ((csr_num == LOONGARCH_CSR_BADI) || (csr_num == LOONGARCH_CSR_CPUID) ||
> + (csr_num == LOONGARCH_CSR_PRCFG1) || (csr_num == LOONGARCH_CSR_PRCFG2) ||
> + (csr_num == LOONGARCH_CSR_PRCFG3) || (csr_num == LOONGARCH_CSR_PGD) ||
> + (csr_num == LOONGARCH_CSR_TVAL) || (csr_num == LOONGARCH_CSR_MISC)) {
Use a switch statement for match arms spanning many values like this;
doing so increases readability and reduces duplication.
> + return true;
> + }
> +
> + return false;
> +}
> +
> +static bool trans_csrrd(DisasContext *ctx, arg_csrrd *a)
> +{
> + TCGv dest = gpr_dst(ctx, a->rd, EXT_NONE);
> +
> + if (check_plv(ctx)) {
> + return false;
> + }
> +
> + unsigned csr_offset = cpu_csr_offset(a->csr);
> + if (csr_offset == 0) {
> + /* CSR is undefined: read as 0 */
"reads return 0"
> + dest = tcg_constant_tl(0);
> + return true;
> + }
> +
> + if ((a->csr == LOONGARCH_CSR_PGD) || (a->csr == LOONGARCH_CSR_CPUID) ||
> + (a->csr == LOONGARCH_CSR_TVAL)) {
Use a switch.
> + gen_helper_csr_rdq(dest, cpu_env, tcg_constant_i64(a->csr));
> + } else {
> + tcg_gen_ld_tl(dest, cpu_env, csr_offset);
> + }
> + return true;
> +}
> +
> +static bool trans_csrwr(DisasContext *ctx, arg_csrwr *a)
> +{
> + TCGv dest = gpr_dst(ctx, a->rd, EXT_NONE);
> + TCGv src1 = gpr_src(ctx, a->rd, EXT_NONE);
> +
> + if (check_plv(ctx) || ro_csr(a->csr)) {
> + return false;
> + }
> +
> + unsigned csr_offset = cpu_csr_offset(a->csr);
> + if (csr_offset == 0) {
> + /* CSR is undefined: write ignored. */
"writes are ignored"
> + return true;
> + }
> +
> + if ((a->csr == LOONGARCH_CSR_ASID) || (a->csr == LOONGARCH_CSR_TCFG) ||
> + (a->csr == LOONGARCH_CSR_TICLR) || (a->csr == LOONGARCH_CSR_ESTAT)) {
Use a switch.
> + gen_helper_csr_wrq(dest, cpu_env, src1, tcg_constant_i64(a->csr));
> + } else {
> + TCGv temp = tcg_temp_new();
> + tcg_gen_ld_tl(temp, cpu_env, csr_offset);
> + tcg_gen_st_tl(src1, cpu_env, csr_offset);
> + tcg_gen_mov_tl(dest, temp);
> + tcg_temp_free(temp);
> +
> + /* Cpu state may be changed, need exit */
"CPU state may be changed, need to exit"
> + if ((a->csr == LOONGARCH_CSR_CRMD) || (a->csr == LOONGARCH_CSR_EUEN)) {
And here if you feel like doing that already. (It's only 2 codes so not
switch-ify-ing is okay too.)
> + tcg_gen_movi_tl(cpu_pc, ctx->base.pc_next + 4);
> + ctx->base.is_jmp = DISAS_EXIT;
> + }
> + }
> +
> + return true;
> +}
> +
> +static bool trans_csrxchg(DisasContext *ctx, arg_csrxchg *a)
> +{
> + TCGv dest = gpr_dst(ctx, a->rd, EXT_NONE);
> + TCGv src1 = gpr_src(ctx, a->rd, EXT_NONE);
> + TCGv src2 = gpr_src(ctx, a->rj, EXT_NONE);
> +
> + if (check_plv(ctx) || ro_csr(a->csr)) {
> + return false;
> + }
> + gen_helper_csr_xchgq(dest, cpu_env, src1, src2, tcg_constant_i64(a->csr));
> + return true;
> +}
> +
> +#endif
> diff --git a/target/loongarch/insns.decode b/target/loongarch/insns.decode
> index 3379d22979..647fcb9def 100644
> --- a/target/loongarch/insns.decode
> +++ b/target/loongarch/insns.decode
> @@ -45,6 +45,8 @@
> &c_offs cj offs
> &offs offs
> &rr_offs rj rd offs
> +&r_csr rd csr
> +&rr_csr rd rj csr
>
> #
> # Formats
> @@ -85,6 +87,8 @@
> @c_offs21 .... .. ................ .. cj:3 ..... &c_offs offs=%offs21
> @offs26 .... .. .......................... &offs offs=%offs26
> @rr_offs16 .... .. ................ rj:5 rd:5 &rr_offs offs=%offs16
> +@r_csr .... .... csr:14 ..... rd:5 &r_csr
> +@rr_csr .... .... csr:14 rj:5 rd:5 &rr_csr
>
> #
> # Fixed point arithmetic operation instruction
> @@ -440,3 +444,12 @@ blt 0110 00 ................ ..... ..... @rr_offs16
> bge 0110 01 ................ ..... ..... @rr_offs16
> bltu 0110 10 ................ ..... ..... @rr_offs16
> bgeu 0110 11 ................ ..... ..... @rr_offs16
> +
> +#
> +# Core instructions
"Privileged instructions"?
> +#
> +{
> + csrrd 0000 0100 .............. 00000 ..... @r_csr
> + csrwr 0000 0100 .............. 00001 ..... @r_csr
> + csrxchg 0000 0100 .............. ..... ..... @rr_csr
> +}
> diff --git a/target/loongarch/meson.build b/target/loongarch/meson.build
> index 6bf2d88104..5fb7542e88 100644
> --- a/target/loongarch/meson.build
> +++ b/target/loongarch/meson.build
> @@ -19,6 +19,7 @@ loongarch_softmmu_ss.add(files(
> 'machine.c',
> 'constant_timer.c',
> 'tlb_helper.c',
> + 'csr_helper.c',
> ))
>
> loongarch_ss.add_all(when: 'CONFIG_TCG', if_true: [loongarch_tcg_ss])
> diff --git a/target/loongarch/translate.c b/target/loongarch/translate.c
> index 2710764653..09771ee43f 100644
> --- a/target/loongarch/translate.c
> +++ b/target/loongarch/translate.c
> @@ -26,6 +26,7 @@ TCGv_i32 cpu_fcsr0;
> TCGv_i64 cpu_fpr[32];
>
> #define DISAS_STOP DISAS_TARGET_0
> +#define DISAS_EXIT DISAS_TARGET_1
>
> static inline int plus_1(DisasContext *ctx, int x)
> {
> @@ -172,6 +173,7 @@ static void gen_set_gpr(int reg_num, TCGv t, DisasExtend dst_ext)
> #include "insn_trans/trans_fmov.c.inc"
> #include "insn_trans/trans_fmemory.c.inc"
> #include "insn_trans/trans_branch.c.inc"
> +#include "insn_trans/trans_core.c.inc"
>
> static void loongarch_tr_translate_insn(DisasContextBase *dcbase, CPUState *cs)
> {
> @@ -209,6 +211,9 @@ static void loongarch_tr_tb_stop(DisasContextBase *dcbase, CPUState *cs)
> break;
> case DISAS_NORETURN:
> break;
> + case DISAS_EXIT:
> + tcg_gen_exit_tb(NULL, 0);
> + break;
> default:
> g_assert_not_reached();
> }
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