target-xtensa: add sample board

Sample board and sample CPU core are used for debug and may be used for
development of custom SoC emulators.

This board has two fixed size memory regions for DTCM and ITCM and
variable length SRAM region.

Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Blue Swirl <blauwirbel@gmail.com>

Makefile.target

@@ -369,6 +369,7 @@ obj-alpha-y = i8259.o mc146818rtc.o
 obj-alpha-y += vga.o cirrus_vga.o
 
 obj-xtensa-y += xtensa_pic.o
+obj-xtensa-y += xtensa_sample.o
 
 main.o: QEMU_CFLAGS+=$(GPROF_CFLAGS)
 

hw/xtensa_sample.c

@@ -0,0 +1,106 @@
+/*
+ * Copyright (c) 2011, Max Filippov, Open Source and Linux Lab.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *     * Redistributions of source code must retain the above copyright
+ *       notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above copyright
+ *       notice, this list of conditions and the following disclaimer in the
+ *       documentation and/or other materials provided with the distribution.
+ *     * Neither the name of the Open Source and Linux Lab nor the
+ *       names of its contributors may be used to endorse or promote products
+ *       derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
+ * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include "sysemu.h"
+#include "boards.h"
+#include "loader.h"
+#include "elf.h"
+#include "memory.h"
+#include "exec-memory.h"
+
+static void xtensa_sample_reset(void *env)
+{
+    cpu_reset(env);
+}
+
+static void xtensa_init(ram_addr_t ram_size,
+        const char *boot_device,
+        const char *kernel_filename, const char *kernel_cmdline,
+        const char *initrd_filename, const char *cpu_model)
+{
+    CPUState *env = NULL;
+    MemoryRegion *ram;
+    const size_t dram_size = 0x10000;
+    const size_t iram_size = 0x20000;
+    int n;
+
+    for (n = 0; n < smp_cpus; n++) {
+        env = cpu_init(cpu_model);
+        if (!env) {
+            fprintf(stderr, "Unable to find CPU definition\n");
+            exit(1);
+        }
+        qemu_register_reset(xtensa_sample_reset, env);
+    }
+
+    ram = g_malloc(sizeof(*ram));
+    memory_region_init_ram(ram, NULL, "xtensa.ram",
+            dram_size + iram_size + ram_size);
+    memory_region_add_subregion(get_system_memory(),
+            0x60000000 - dram_size - iram_size, ram);
+
+    if (kernel_filename) {
+        uint64_t elf_entry;
+        uint64_t elf_lowaddr;
+#ifdef TARGET_WORDS_BIGENDIAN
+        int success = load_elf(kernel_filename, NULL, NULL, &elf_entry,
+                &elf_lowaddr, NULL, 1, ELF_MACHINE, 0);
+#else
+        int success = load_elf(kernel_filename, NULL, NULL, &elf_entry,
+                &elf_lowaddr, NULL, 0, ELF_MACHINE, 0);
+#endif
+        if (success > 0) {
+            env->pc = elf_entry;
+        }
+    }
+}
+
+static void xtensa_sample_init(ram_addr_t ram_size,
+                     const char *boot_device,
+                     const char *kernel_filename, const char *kernel_cmdline,
+                     const char *initrd_filename, const char *cpu_model)
+{
+    if (!cpu_model) {
+        cpu_model = "sample-xtensa-core";
+    }
+    xtensa_init(ram_size, boot_device, kernel_filename, kernel_cmdline,
+                  initrd_filename, cpu_model);
+}
+
+static QEMUMachine xtensa_sample_machine = {
+    .name = "sample-xtensa-machine",
+    .desc = "Sample Xtensa machine (sample Xtensa core)",
+    .init = xtensa_sample_init,
+    .max_cpus = 4,
+};
+
+static void xtensa_sample_machine_init(void)
+{
+    qemu_register_machine(&xtensa_sample_machine);
+}
+
+machine_init(xtensa_sample_machine_init);