[RFC PATCH v6 08/29] target/loongarch: Add LoongArch IOCSR instruction

[Xiaojuan Yang]

This includes:
- IOCSR{RD/WR}.{B/H/W/D}

Signed-off-by: Xiaojuan Yang <yangxiaojuan@loongson.cn>
Signed-off-by: Song Gao <gaosong@loongson.cn>
---
 target/loongarch/cpu.h                        |   4 +
 target/loongarch/disas.c                      |   8 +
 target/loongarch/helper.h                     |   2 +
 .../insn_trans/trans_privileged.c.inc         | 103 +++++++++++++
 target/loongarch/insns.decode                 |   9 ++
 target/loongarch/iocsr_helper.c               | 139 ++++++++++++++++++
 target/loongarch/meson.build                  |   1 +
 7 files changed, 266 insertions(+)
 create mode 100644 target/loongarch/iocsr_helper.c

diff --git a/target/loongarch/cpu.h b/target/loongarch/cpu.h
index 9a8306ecbb..581da7b423 100644
--- a/target/loongarch/cpu.h
+++ b/target/loongarch/cpu.h
@@ -151,6 +151,7 @@ extern const char * const fregnames[32];
 
 #define N_IRQS      14
 #define IRQ_TIMER   11
+#define IRQ_IPI     12
 
 #define LOONGARCH_STLB         2048 /* 2048 STLB */
 #define LOONGARCH_MTLB         64   /* 64 MTLB */
@@ -249,6 +250,9 @@ struct CPULoongArchState {
 
 #ifndef CONFIG_USER_ONLY
     LoongArchTLB  tlb[LOONGARCH_TLB_MAX];
+
+    AddressSpace address_space_iocsr;
+    MemoryRegion system_iocsr;
 #endif
 };
 
diff --git a/target/loongarch/disas.c b/target/loongarch/disas.c
index b83022468e..90f469bdc0 100644
--- a/target/loongarch/disas.c
+++ b/target/loongarch/disas.c
@@ -532,6 +532,14 @@ INSN(bgeu,         rr_offs)
 INSN(csrrd,        r_csr)
 INSN(csrwr,        r_csr)
 INSN(csrxchg,      rr_csr)
+INSN(iocsrrd_b,    rr)
+INSN(iocsrrd_h,    rr)
+INSN(iocsrrd_w,    rr)
+INSN(iocsrrd_d,    rr)
+INSN(iocsrwr_b,    rr)
+INSN(iocsrwr_h,    rr)
+INSN(iocsrwr_w,    rr)
+INSN(iocsrwr_d,    rr)
 
 #define output_fcmp(C, PREFIX, SUFFIX)                                         
\
 {                                                                              
\
diff --git a/target/loongarch/helper.h b/target/loongarch/helper.h
index 036dbf31f8..1bcd082858 100644
--- a/target/loongarch/helper.h
+++ b/target/loongarch/helper.h
@@ -98,4 +98,6 @@ DEF_HELPER_FLAGS_2(set_rounding_mode, TCG_CALL_NO_RWG, void, 
env, i32)
 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)
+DEF_HELPER_3(iocsr_read, i64, env, tl, i32)
+DEF_HELPER_4(iocsr_write, void, env, tl, tl, i32)
 #endif /* !CONFIG_USER_ONLY */
diff --git a/target/loongarch/insn_trans/trans_privileged.c.inc 
b/target/loongarch/insn_trans/trans_privileged.c.inc
index 9354697894..30f1e688e8 100644
--- a/target/loongarch/insn_trans/trans_privileged.c.inc
+++ b/target/loongarch/insn_trans/trans_privileged.c.inc
@@ -18,6 +18,14 @@ static bool trans_##name(DisasContext *ctx, arg_##name * a)  
\
 GEN_FALSE_TRANS(csrrd)
 GEN_FALSE_TRANS(csrwr)
 GEN_FALSE_TRANS(csrxchg)
+GEN_FALSE_TRANS(iocsrrd_b)
+GEN_FALSE_TRANS(iocsrrd_h)
+GEN_FALSE_TRANS(iocsrrd_w)
+GEN_FALSE_TRANS(iocsrrd_d)
+GEN_FALSE_TRANS(iocsrwr_b)
+GEN_FALSE_TRANS(iocsrwr_h)
+GEN_FALSE_TRANS(iocsrwr_w)
+GEN_FALSE_TRANS(iocsrwr_d)
 
 #else
 
@@ -122,4 +130,99 @@ static bool trans_csrxchg(DisasContext *ctx, arg_csrxchg 
*a)
     return true;
 }
 
+static bool trans_iocsrrd_b(DisasContext *ctx, arg_iocsrrd_b *a)
+{
+    TCGv dest = gpr_dst(ctx, a->rd, EXT_NONE);
+    TCGv src1 = gpr_src(ctx, a->rj, EXT_NONE);
+
+    if (check_plv(ctx)) {
+        return false;
+    }
+    gen_helper_iocsr_read(dest, cpu_env, src1, tcg_constant_i32(1));
+    return true;
+}
+
+static bool trans_iocsrrd_h(DisasContext *ctx, arg_iocsrrd_h *a)
+{
+    TCGv dest = gpr_dst(ctx, a->rd, EXT_NONE);
+    TCGv src1 = gpr_src(ctx, a->rj, EXT_NONE);
+
+    if (check_plv(ctx)) {
+        return false;
+    }
+    gen_helper_iocsr_read(dest, cpu_env, src1, tcg_constant_i32(2));
+    return true;
+}
+
+static bool trans_iocsrrd_w(DisasContext *ctx, arg_iocsrrd_w *a)
+{
+    TCGv dest = gpr_dst(ctx, a->rd, EXT_NONE);
+    TCGv src1 = gpr_src(ctx, a->rj, EXT_NONE);
+
+    if (check_plv(ctx)) {
+        return false;
+    }
+    gen_helper_iocsr_read(dest, cpu_env, src1, tcg_constant_i32(4));
+    return true;
+}
+
+static bool trans_iocsrrd_d(DisasContext *ctx, arg_iocsrrd_d *a)
+{
+    TCGv dest = gpr_dst(ctx, a->rd, EXT_NONE);
+    TCGv src1 = gpr_src(ctx, a->rj, EXT_NONE);
+
+    if (check_plv(ctx)) {
+        return false;
+    }
+    gen_helper_iocsr_read(dest, cpu_env, src1, tcg_constant_i32(8));
+    return true;
+}
+
+static bool trans_iocsrwr_b(DisasContext *ctx, arg_iocsrwr_b *a)
+{
+    TCGv val = gpr_src(ctx, a->rd, EXT_NONE);
+    TCGv addr = gpr_src(ctx, a->rj, EXT_NONE);
+
+    if (check_plv(ctx)) {
+        return false;
+    }
+    gen_helper_iocsr_write(cpu_env, addr, val, tcg_constant_i32(1));
+    return true;
+}
+
+static bool trans_iocsrwr_h(DisasContext *ctx, arg_iocsrwr_h *a)
+{
+    TCGv val = gpr_src(ctx, a->rd, EXT_NONE);
+    TCGv addr = gpr_src(ctx, a->rj, EXT_NONE);
+
+    if (check_plv(ctx)) {
+        return false;
+    }
+    gen_helper_iocsr_write(cpu_env, addr, val, tcg_constant_i32(2));
+    return true;
+}
+
+static bool trans_iocsrwr_w(DisasContext *ctx, arg_iocsrwr_w *a)
+{
+    TCGv val = gpr_src(ctx, a->rd, EXT_NONE);
+    TCGv addr = gpr_src(ctx, a->rj, EXT_NONE);
+
+    if (check_plv(ctx)) {
+        return false;
+    }
+    gen_helper_iocsr_write(cpu_env, addr, val, tcg_constant_i32(4));
+    return true;
+}
+
+static bool trans_iocsrwr_d(DisasContext *ctx, arg_iocsrwr_d *a)
+{
+    TCGv val = gpr_src(ctx, a->rd, EXT_NONE);
+    TCGv addr = gpr_src(ctx, a->rj, EXT_NONE);
+
+    if (check_plv(ctx)) {
+        return false;
+    }
+    gen_helper_iocsr_write(cpu_env, addr, val, tcg_constant_i32(8));
+    return true;
+}
 #endif
diff --git a/target/loongarch/insns.decode b/target/loongarch/insns.decode
index 647fcb9def..9a43f288c3 100644
--- a/target/loongarch/insns.decode
+++ b/target/loongarch/insns.decode
@@ -453,3 +453,12 @@ bgeu            0110 11 ................ ..... .....     
@rr_offs16
   csrwr             0000 0100 .............. 00001 .....     @r_csr
   csrxchg           0000 0100 .............. ..... .....     @rr_csr
 }
+
+iocsrrd_b        0000 01100100 10000 00000 ..... .....    @rr
+iocsrrd_h        0000 01100100 10000 00001 ..... .....    @rr
+iocsrrd_w        0000 01100100 10000 00010 ..... .....    @rr
+iocsrrd_d        0000 01100100 10000 00011 ..... .....    @rr
+iocsrwr_b        0000 01100100 10000 00100 ..... .....    @rr
+iocsrwr_h        0000 01100100 10000 00101 ..... .....    @rr
+iocsrwr_w        0000 01100100 10000 00110 ..... .....    @rr
+iocsrwr_d        0000 01100100 10000 00111 ..... .....    @rr
diff --git a/target/loongarch/iocsr_helper.c b/target/loongarch/iocsr_helper.c
new file mode 100644
index 0000000000..72ac3806b6
--- /dev/null
+++ b/target/loongarch/iocsr_helper.c
@@ -0,0 +1,139 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ * Copyright (c) 2021 Loongson Technology Corporation Limited
+ *
+ * Helpers for IOCSR reads/writes
+ */
+
+#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"
+
+uint64_t helper_iocsr_read(CPULoongArchState *env, target_ulong r_addr,
+                           uint32_t size)
+{
+    int cpuid = env_cpu(env)->cpu_index;
+    CPUState  *cs = qemu_get_cpu(cpuid);
+    env = cs->env_ptr;
+    uint64_t ret;
+
+    /*
+     * Adjust the per core address such as 0x10xx(IPI)/0x18xx(EXTIOI)
+     */
+    if (((r_addr & 0xff00) == 0x1000) || ((r_addr & 0xff00) == 0x1800)) {
+        r_addr = r_addr + ((target_ulong)(cpuid & 0x3) << 8);
+    }
+
+    switch (size) {
+    case 1:
+        ret = address_space_ldub(&env->address_space_iocsr, r_addr,
+                                 MEMTXATTRS_UNSPECIFIED, NULL);
+        break;
+    case 2:
+        ret = address_space_lduw(&env->address_space_iocsr, r_addr,
+                                 MEMTXATTRS_UNSPECIFIED, NULL);
+        break;
+    case 4:
+        ret = address_space_ldl(&env->address_space_iocsr, r_addr,
+                                MEMTXATTRS_UNSPECIFIED, NULL);
+        break;
+    case 8:
+        ret = address_space_ldq(&env->address_space_iocsr, r_addr,
+                                MEMTXATTRS_UNSPECIFIED, NULL);
+        break;
+    default:
+        break;
+    }
+
+    return ret;
+}
+
+void helper_iocsr_write(CPULoongArchState *env, target_ulong w_addr,
+                        target_ulong val, uint32_t size)
+{
+    int cpuid = env_cpu(env)->cpu_index;
+    CPUState *cs = qemu_get_cpu(cpuid);
+    int mask, i;
+    env = cs->env_ptr;
+
+    /*
+     * For IPI send, Mailbox send and ANY send, adjust the addr and
+     * val accordingly. The IOCSR writes are turned to different
+     * MMIO writes respectively
+     */
+    switch (w_addr) {
+    case 0x1040: /* IPI send */
+        cpuid = (val >> 16) & 0x3ff;
+        val = 1UL << (val & 0x1f);
+        if (val) {
+            qemu_mutex_lock_iothread();
+            cs = qemu_get_cpu(cpuid);
+            env = cs->env_ptr;
+            env->CSR_ESTAT |= 1 << IRQ_IPI;
+            cpu_interrupt(cs, CPU_INTERRUPT_HARD);
+            qemu_mutex_unlock_iothread();
+        }
+        break;
+    case 0x1048: /* Mail Send */
+        cpuid = (val >> 16) & 0x3ff;
+        w_addr = 0x1020 + (val & 0x1c);
+        val = val >> 32;
+        mask = (val >> 27) & 0xf;
+        size = 4;
+        env = (qemu_get_cpu(cpuid))->env_ptr;
+        break;
+    case 0x1158: /* ANY send */
+        cpuid = (val >> 16) & 0x3ff;
+        w_addr = val & 0xffff;
+        val = val >> 32;
+        mask = (val >> 27) & 0xf;
+        size = 1;
+        env = (qemu_get_cpu(cpuid))->env_ptr;
+
+        for (i = 0; i < 4; i++) {
+            if (!((mask >> i) & 1)) {
+                address_space_stb(&env->address_space_iocsr, w_addr,
+                                  val, MEMTXATTRS_UNSPECIFIED, NULL);
+            }
+            w_addr = w_addr + 1;
+            val = val >> 8;
+        }
+        return;
+    default:
+       break;
+    }
+
+    if (((w_addr & 0xff00) == 0x1000) || ((w_addr & 0xff00) == 0x1800)) {
+        w_addr = w_addr + ((target_ulong)(cpuid & 0x3) << 8);
+    }
+
+    switch (size) {
+    case 1:
+        address_space_stb(&env->address_space_iocsr, w_addr,
+                          val, MEMTXATTRS_UNSPECIFIED, NULL);
+        break;
+    case 2:
+        address_space_stw(&env->address_space_iocsr, w_addr,
+                          val, MEMTXATTRS_UNSPECIFIED, NULL);
+        break;
+    case 4:
+        address_space_stl(&env->address_space_iocsr, w_addr,
+                          val, MEMTXATTRS_UNSPECIFIED, NULL);
+        break;
+    case 8:
+        address_space_stq(&env->address_space_iocsr, w_addr,
+                          val, MEMTXATTRS_UNSPECIFIED, NULL);
+        break;
+    default:
+        break;
+    }
+}
diff --git a/target/loongarch/meson.build b/target/loongarch/meson.build
index 5fb7542e88..072684ca6d 100644
--- a/target/loongarch/meson.build
+++ b/target/loongarch/meson.build
@@ -20,6 +20,7 @@ loongarch_softmmu_ss.add(files(
   'constant_timer.c',
   'tlb_helper.c',
   'csr_helper.c',
+  'iocsr_helper.c',
 ))
 
 loongarch_ss.add_all(when: 'CONFIG_TCG', if_true: [loongarch_tcg_ss])
-- 
2.27.0