microblaze: Add translation routines.

Signed-off-by: Edgar E. Iglesias <edgar.iglesias@gmail.com>

target-microblaze/op_helper.c

@@ -0,0 +1,216 @@
+/*
+ *  Microblaze helper routines.
+ *
+ *  Copyright (c) 2009 Edgar E. Iglesias <edgar.iglesias@gmail.com>.
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston MA  02110-1301 USA
+ */
+
+#include <assert.h>
+#include "exec.h"
+#include "helper.h"
+#include "host-utils.h"
+
+#define D(x)
+
+#if !defined(CONFIG_USER_ONLY)
+#define MMUSUFFIX _mmu
+#define SHIFT 0
+#include "softmmu_template.h"
+#define SHIFT 1
+#include "softmmu_template.h"
+#define SHIFT 2
+#include "softmmu_template.h"
+#define SHIFT 3
+#include "softmmu_template.h"
+
+/* Try to fill the TLB and return an exception if error. If retaddr is
+   NULL, it means that the function was called in C code (i.e. not
+   from generated code or from helper.c) */
+/* XXX: fix it to restore all registers */
+void tlb_fill (target_ulong addr, int is_write, int mmu_idx, void *retaddr)
+{
+    TranslationBlock *tb;
+    CPUState *saved_env;
+    unsigned long pc;
+    int ret;
+
+    /* XXX: hack to restore env in all cases, even if not called from
+       generated code */
+    saved_env = env;
+    env = cpu_single_env;
+
+    ret = cpu_mb_handle_mmu_fault(env, addr, is_write, mmu_idx, 1);
+    if (unlikely(ret)) {
+        if (retaddr) {
+            /* now we have a real cpu fault */
+            pc = (unsigned long)retaddr;
+            tb = tb_find_pc(pc);
+            if (tb) {
+                /* the PC is inside the translated code. It means that we have
+                   a virtual CPU fault */
+                cpu_restore_state(tb, env, pc, NULL);
+            }
+        }
+        cpu_loop_exit();
+    }
+    env = saved_env;
+}
+#endif
+
+void helper_raise_exception(uint32_t index)
+{
+    env->exception_index = index;
+    cpu_loop_exit();
+}
+
+void helper_debug(void)
+{
+    int i;
+
+    qemu_log("PC=%8.8x\n", env->sregs[SR_PC]);
+    for (i = 0; i < 32; i++) {
+        qemu_log("r%2.2d=%8.8x ", i, env->regs[i]);
+        if ((i + 1) % 4 == 0)
+            qemu_log("\n");
+    }
+    qemu_log("\n\n");
+}
+
+static inline uint32_t compute_carry(uint32_t a, uint32_t b, uint32_t cin)
+{
+    uint32_t cout = 0;
+
+    if ((b == ~0) && cin)
+        cout = 1;
+    else if ((~0 - a) < (b + cin))
+        cout = 1;
+    return cout;
+}
+
+uint32_t helper_cmp(uint32_t a, uint32_t b)
+{
+    uint32_t t;
+
+    t = b + ~a + 1;
+    if ((b & 0x80000000) ^ (a & 0x80000000))
+        t = (t & 0x7fffffff) | (b & 0x80000000);
+    return t;
+}
+
+uint32_t helper_cmpu(uint32_t a, uint32_t b)
+{
+    uint32_t t;
+
+    t = b + ~a + 1;
+    if ((b & 0x80000000) ^ (a & 0x80000000))
+        t = (t & 0x7fffffff) | (a & 0x80000000);
+    return t;
+}
+
+uint32_t helper_addkc(uint32_t a, uint32_t b, uint32_t k, uint32_t c)
+{
+    uint32_t d, cf = 0, ncf;
+
+    if (c)
+        cf = env->sregs[SR_MSR] >> 31;
+    assert(cf == 0 || cf == 1);
+    d = a + b + cf;
+
+    if (!k) {
+        ncf = compute_carry(a, b, cf);
+        assert(ncf == 0 || ncf == 1);
+        if (ncf)
+            env->sregs[SR_MSR] |= MSR_C | MSR_CC;
+        else
+            env->sregs[SR_MSR] &= ~(MSR_C | MSR_CC);
+    }
+    D(qemu_log("%x = %x + %x cf=%d ncf=%d k=%d c=%d\n",
+               d, a, b, cf, ncf, k, c));
+    return d;
+}
+
+uint32_t helper_subkc(uint32_t a, uint32_t b, uint32_t k, uint32_t c)
+{
+    uint32_t d, cf = 1, ncf;
+
+    if (c)
+        cf = env->sregs[SR_MSR] >> 31; 
+    assert(cf == 0 || cf == 1);
+    d = b + ~a + cf;
+
+    if (!k) {
+        ncf = compute_carry(b, ~a, cf);
+        assert(ncf == 0 || ncf == 1);
+        if (ncf)
+            env->sregs[SR_MSR] |= MSR_C | MSR_CC;
+        else
+            env->sregs[SR_MSR] &= ~(MSR_C | MSR_CC);
+    }
+    D(qemu_log("%x = %x + %x cf=%d ncf=%d k=%d c=%d\n",
+               d, a, b, cf, ncf, k, c));
+    return d;
+}
+
+static inline int div_prepare(uint32_t a, uint32_t b)
+{
+    if (b == 0) {
+        env->sregs[SR_MSR] |= MSR_DZ;
+        /* FIXME: Raise the div by zero exception.  */
+        return 0;
+    }
+    env->sregs[SR_MSR] &= ~MSR_DZ;
+    return 1;
+}
+
+uint32_t helper_divs(uint32_t a, uint32_t b)
+{
+    if (!div_prepare(a, b))
+        return 0;
+    return (int32_t)a / (int32_t)b;
+}
+
+uint32_t helper_divu(uint32_t a, uint32_t b)
+{
+    if (!div_prepare(a, b))
+        return 0;
+    return a / b;
+}
+
+uint32_t helper_pcmpbf(uint32_t a, uint32_t b)
+{
+    unsigned int i;
+    uint32_t mask = 0xff000000;
+
+    for (i = 0; i < 4; i++) {
+        if ((a & mask) == (b & mask))
+            return i + 1;
+        mask >>= 8;
+    }
+    return 0;
+}
+
+#if !defined(CONFIG_USER_ONLY)
+/* Writes/reads to the MMU's special regs end up here.  */
+uint32_t helper_mmu_read(uint32_t rn)
+{
+    return mmu_read(env, rn);
+}
+
+void helper_mmu_write(uint32_t rn, uint32_t v)
+{
+    mmu_write(env, rn, v);
+}
+#endif