msf2: Add Smartfusion2 SPI controller

Modelled Microsemi's Smartfusion2 SPI controller.

Signed-off-by: Subbaraya Sundeep <sundeep.lkml@gmail.com>
Reviewed-by: Alistair Francis <alistair.francis@xilinx.com>
Tested-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-id: 20170920201737.25723-4-f4bug@amsat.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

include/hw/ssi/mss-spi.h

@@ -0,0 +1,58 @@
+/*
+ * Microsemi SmartFusion2 SPI
+ *
+ * Copyright (c) 2017 Subbaraya Sundeep <sundeep.lkml@gmail.com>
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#ifndef HW_MSS_SPI_H
+#define HW_MSS_SPI_H
+
+#include "hw/sysbus.h"
+#include "hw/ssi/ssi.h"
+#include "qemu/fifo32.h"
+
+#define TYPE_MSS_SPI   "mss-spi"
+#define MSS_SPI(obj)   OBJECT_CHECK(MSSSpiState, (obj), TYPE_MSS_SPI)
+
+#define R_SPI_MAX             16
+
+typedef struct MSSSpiState {
+    SysBusDevice parent_obj;
+
+    MemoryRegion mmio;
+
+    qemu_irq irq;
+
+    qemu_irq cs_line;
+
+    SSIBus *spi;
+
+    Fifo32 rx_fifo;
+    Fifo32 tx_fifo;
+
+    int fifo_depth;
+    uint32_t frame_count;
+    bool enabled;
+
+    uint32_t regs[R_SPI_MAX];
+} MSSSpiState;
+
+#endif /* HW_MSS_SPI_H */