CRIS MMU emulation, by Edgar E. Iglesias.

git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@3362 c046a42c-6fe2-441c-8c8c-71466251a162

1 files changed, 147 insertions, 0 deletions

diff --git a/target-cris/mmu.c b/target-cris/mmu.c
new file mode 100644
index 0000000000..56299b7dd1
--- /dev/null
+++ b/target-cris/mmu.c
@@ -0,0 +1,147 @@
+/*
+ *  CRIS mmu emulation.
+ *
+ *  Copyright (c) 2007 AXIS Communications AB
+ *  Written by Edgar E. Iglesias.
+ *
+ * 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., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+#ifndef CONFIG_USER_ONLY
+
+#include <stdio.h>
+#include <string.h>
+#include <stdlib.h>
+
+#include "config.h"
+#include "cpu.h"
+#include "mmu.h"
+#include "exec-all.h"
+
+
+static int cris_mmu_enabled(uint32_t rw_gc_cfg)
+{
+	return (rw_gc_cfg & 12) != 0;
+}
+
+static int cris_mmu_segmented_addr(int seg, uint32_t rw_mm_cfg)
+{
+	return (1 << seg) & rw_mm_cfg;
+}
+
+static uint32_t cris_mmu_translate_seg(CPUState *env, int seg)
+{
+	uint32_t base;
+	int i;
+
+	if (seg < 8)
+		base = env->sregs[SFR_RW_MM_KBASE_LO];
+	else
+		base = env->sregs[SFR_RW_MM_KBASE_HI];
+
+	i = seg & 7;
+	base >>= i * 4;
+	base &= 15;
+
+	base <<= 28;
+	return base;
+}
+/* Used by the tlb decoder.  */
+#define EXTRACT_FIELD(src, start, end) \
+            (((src) >> start) & ((1 << (end - start + 1)) - 1))
+
+static int cris_mmu_translate_page(struct cris_mmu_result_t *res,
+				   CPUState *env, uint32_t vaddr,
+				   int rw, int usermode)
+{
+	unsigned int vpage;
+	unsigned int idx;
+	uint32_t lo, hi;
+	uint32_t vpn, pfn = 0, pid, fg, fv, fk, fw, fx;
+	int i, match = 0;
+
+	vpage = vaddr >> 13;
+	idx = vpage & 31;
+	vpage >>= 4;
+
+	/* We know the index which to check on each set.
+	   Scan both I and D.  */
+	for (i = 0; i < 4; i++)
+	{
+		lo = env->tlbsets[0][i][idx].lo;
+		hi = env->tlbsets[0][i][idx].hi;
+
+		vpn = EXTRACT_FIELD(hi, 13, 31);
+		pid = EXTRACT_FIELD(hi, 0, 7);
+
+		if (vpn == vpage
+		    && pid == env->pregs[SR_PID]) {
+			match = 1;
+			break;
+		}
+	}
+
+	if (match) {
+		pfn = EXTRACT_FIELD(lo, 13, 31);
+		fg = EXTRACT_FIELD(lo, 4, 4);
+		fv = EXTRACT_FIELD(lo, 3, 3);
+		fk = EXTRACT_FIELD(lo, 2, 2);
+		fw = EXTRACT_FIELD(lo, 1, 1);
+		fx = EXTRACT_FIELD(lo, 0, 0);
+	}
+	printf ("%s match=%d vaddr=%x vpage=%x vpn=%x pfn=%x pid=%x %x\n",
+		__func__, match,
+		vaddr, vpage,
+		vpn, pfn, pid, env->pregs[SR_PID]);
+	res->pfn = pfn;
+	return !match;
+}
+
+int cris_mmu_translate(struct cris_mmu_result_t *res,
+		       CPUState *env, uint32_t vaddr,
+		       int rw, int is_user)
+{
+	uint32_t phy = vaddr;
+	int seg;
+	int miss = 0;
+
+	if (!cris_mmu_enabled(env->sregs[SFR_RW_GC_CFG])) {
+		res->phy = vaddr;
+		return 0;
+	}
+
+	seg = vaddr >> 28;
+	if (cris_mmu_segmented_addr(seg, env->sregs[SFR_RW_MM_CFG]))
+	{
+		uint32_t base;
+
+		miss = 0;
+		base = cris_mmu_translate_seg(env, seg);
+		phy = base | (0x0fffffff & vaddr);
+		res->phy = phy;
+	}
+	else
+	{
+		miss = cris_mmu_translate_page(res, env, vaddr, rw, is_user);
+		if (!miss) {
+			phy &= 8191;
+			phy |= (res->pfn << 13);
+			res->phy = phy;
+		}
+	}
+//	printf ("miss=%d v=%x -> p=%x\n", miss, vaddr, phy);
+	return miss;
+}
+#endif