hw/ssi: Add Ibex SPI device model

Adds the SPI_HOST device model for ibex. The device specification is as per
[1]. The model has been tested on opentitan with spi_host unit tests
written for TockOS.

[1] https://docs.opentitan.org/hw/ip/spi_host/doc/

Signed-off-by: Wilfred Mallawa <wilfred.mallawa@wdc.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-Id: <20220303045426.511588-1-alistair.francis@opensource.wdc.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>

1 files changed, 94 insertions, 0 deletions

diff --git a/include/hw/ssi/ibex_spi_host.h b/include/hw/ssi/ibex_spi_host.h
new file mode 100644
index 0000000000..3fedcb6805
--- /dev/null
+++ b/include/hw/ssi/ibex_spi_host.h
@@ -0,0 +1,94 @@
+
+/*
+ * QEMU model of the Ibex SPI Controller
+ * SPEC Reference: https://docs.opentitan.org/hw/ip/spi_host/doc/
+ *
+ * Copyright (C) 2022 Western Digital
+ *
+ * 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 IBEX_SPI_HOST_H
+#define IBEX_SPI_HOST_H
+
+#include "hw/sysbus.h"
+#include "hw/hw.h"
+#include "hw/ssi/ssi.h"
+#include "qemu/fifo8.h"
+#include "qom/object.h"
+#include "hw/registerfields.h"
+#include "qemu/timer.h"
+
+#define TYPE_IBEX_SPI_HOST "ibex-spi"
+#define IBEX_SPI_HOST(obj) \
+    OBJECT_CHECK(IbexSPIHostState, (obj), TYPE_IBEX_SPI_HOST)
+
+/* SPI Registers */
+#define IBEX_SPI_HOST_INTR_STATE         (0x00 / 4)  /* rw */
+#define IBEX_SPI_HOST_INTR_ENABLE        (0x04 / 4)  /* rw */
+#define IBEX_SPI_HOST_INTR_TEST          (0x08 / 4)  /* wo */
+#define IBEX_SPI_HOST_ALERT_TEST         (0x0c / 4)  /* wo */
+#define IBEX_SPI_HOST_CONTROL            (0x10 / 4)  /* rw */
+#define IBEX_SPI_HOST_STATUS             (0x14 / 4)  /* ro */
+#define IBEX_SPI_HOST_CONFIGOPTS         (0x18 / 4)  /* rw */
+#define IBEX_SPI_HOST_CSID               (0x1c / 4)  /* rw */
+#define IBEX_SPI_HOST_COMMAND            (0x20 / 4)  /* wo */
+/* RX/TX Modelled by FIFO */
+#define IBEX_SPI_HOST_RXDATA             (0x24 / 4)
+#define IBEX_SPI_HOST_TXDATA             (0x28 / 4)
+
+#define IBEX_SPI_HOST_ERROR_ENABLE       (0x2c / 4)  /* rw */
+#define IBEX_SPI_HOST_ERROR_STATUS       (0x30 / 4)  /* rw */
+#define IBEX_SPI_HOST_EVENT_ENABLE       (0x34 / 4)  /* rw */
+
+/* FIFO Len in Bytes */
+#define IBEX_SPI_HOST_TXFIFO_LEN         288
+#define IBEX_SPI_HOST_RXFIFO_LEN         256
+
+/*  Max Register (Based on addr) */
+#define IBEX_SPI_HOST_MAX_REGS           (IBEX_SPI_HOST_EVENT_ENABLE + 1)
+
+/* MISC */
+#define TX_INTERRUPT_TRIGGER_DELAY_NS    100
+#define BIDIRECTIONAL_TRANSFER           3
+
+typedef struct {
+    /* <private> */
+    SysBusDevice parent_obj;
+
+    /* <public> */
+    MemoryRegion mmio;
+    uint32_t regs[IBEX_SPI_HOST_MAX_REGS];
+    /* Multi-reg that sets config opts per CS */
+    uint32_t *config_opts;
+    Fifo8 rx_fifo;
+    Fifo8 tx_fifo;
+    QEMUTimer *fifo_trigger_handle;
+
+    qemu_irq event;
+    qemu_irq host_err;
+    uint32_t num_cs;
+    qemu_irq *cs_lines;
+    SSIBus *ssi;
+
+    /* Used to track the init status, for replicating TXDATA ghost writes */
+    bool init_status;
+} IbexSPIHostState;
+
+#endif