hw/char: Add Microchip PolarFire SoC MMUART emulation

Microchip PolarFire SoC MMUART is ns16550 compatible, with some
additional registers. Create a simple MMUART model built on top
of the existing ns16550 model.

Signed-off-by: Bin Meng <bin.meng@windriver.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-Id: <1598924352-89526-6-git-send-email-bmeng.cn@gmail.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>

5 files changed, 153 insertions, 0 deletions

diff --git a/MAINTAINERS b/MAINTAINERS
index 9641ed3..d17b08f 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -1321,7 +1321,9 @@ M: Bin Meng <bin.meng@windriver.com>
 L: qemu-riscv@nongnu.org
 S: Supported
 F: hw/riscv/microchip_pfsoc.c
+F: hw/char/mchp_pfsoc_mmuart.c
 F: include/hw/riscv/microchip_pfsoc.h
+F: include/hw/char/mchp_pfsoc_mmuart.h
 
 RX Machines
 -----------
diff --git a/hw/char/Kconfig b/hw/char/Kconfig
index b7e0e4d..1d64555 100644
--- a/hw/char/Kconfig
+++ b/hw/char/Kconfig
@@ -52,3 +52,6 @@ config RENESAS_SCI
 
 config AVR_USART
     bool
+
+config MCHP_PFSOC_MMUART
+    bool
diff --git a/hw/char/mchp_pfsoc_mmuart.c b/hw/char/mchp_pfsoc_mmuart.c
new file mode 100644
index 0000000..8a002b0
--- /dev/null
+++ b/hw/char/mchp_pfsoc_mmuart.c
@@ -0,0 +1,86 @@
+/*
+ * Microchip PolarFire SoC MMUART emulation
+ *
+ * Copyright (c) 2020 Wind River Systems, Inc.
+ *
+ * Author:
+ *   Bin Meng <bin.meng@windriver.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 or
+ * (at your option) version 3 of the License.
+ *
+ * This program 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 General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "qemu/osdep.h"
+#include "qemu/log.h"
+#include "chardev/char.h"
+#include "exec/address-spaces.h"
+#include "hw/char/mchp_pfsoc_mmuart.h"
+
+static uint64_t mchp_pfsoc_mmuart_read(void *opaque, hwaddr addr, unsigned size)
+{
+    MchpPfSoCMMUartState *s = opaque;
+
+    if (addr >= MCHP_PFSOC_MMUART_REG_SIZE) {
+        qemu_log_mask(LOG_GUEST_ERROR, "%s: read: addr=0x%" HWADDR_PRIx "\n",
+                      __func__, addr);
+        return 0;
+    }
+
+    return s->reg[addr / sizeof(uint32_t)];
+}
+
+static void mchp_pfsoc_mmuart_write(void *opaque, hwaddr addr,
+                                    uint64_t value, unsigned size)
+{
+    MchpPfSoCMMUartState *s = opaque;
+    uint32_t val32 = (uint32_t)value;
+
+    if (addr >= MCHP_PFSOC_MMUART_REG_SIZE) {
+        qemu_log_mask(LOG_GUEST_ERROR, "%s: bad write: addr=0x%" HWADDR_PRIx
+                      " v=0x%x\n", __func__, addr, val32);
+        return;
+    }
+
+    s->reg[addr / sizeof(uint32_t)] = val32;
+}
+
+static const MemoryRegionOps mchp_pfsoc_mmuart_ops = {
+    .read = mchp_pfsoc_mmuart_read,
+    .write = mchp_pfsoc_mmuart_write,
+    .endianness = DEVICE_LITTLE_ENDIAN,
+    .impl = {
+        .min_access_size = 4,
+        .max_access_size = 4,
+    },
+};
+
+MchpPfSoCMMUartState *mchp_pfsoc_mmuart_create(MemoryRegion *sysmem,
+    hwaddr base, qemu_irq irq, Chardev *chr)
+{
+    MchpPfSoCMMUartState *s;
+
+    s = g_new0(MchpPfSoCMMUartState, 1);
+
+    memory_region_init_io(&s->iomem, NULL, &mchp_pfsoc_mmuart_ops, s,
+                          "mchp.pfsoc.mmuart", 0x1000);
+
+    s->base = base;
+    s->irq = irq;
+
+    s->serial = serial_mm_init(sysmem, base, 2, irq, 399193, chr,
+                               DEVICE_LITTLE_ENDIAN);
+
+    memory_region_add_subregion(sysmem, base + 0x20, &s->iomem);
+
+    return s;
+}
diff --git a/hw/char/meson.build b/hw/char/meson.build
index e888215..ae27932 100644
--- a/hw/char/meson.build
+++ b/hw/char/meson.build
@@ -32,6 +32,7 @@ softmmu_ss.add(when: 'CONFIG_RASPI', if_true: files('bcm2835_aux.c'))
 softmmu_ss.add(when: 'CONFIG_RENESAS_SCI', if_true: files('renesas_sci.c'))
 softmmu_ss.add(when: 'CONFIG_SH4', if_true: files('sh_serial.c'))
 softmmu_ss.add(when: 'CONFIG_STM32F2XX_USART', if_true: files('stm32f2xx_usart.c'))
+softmmu_ss.add(when: 'CONFIG_MCHP_PFSOC_MMUART', if_true: files('mchp_pfsoc_mmuart.c'))
 
 specific_ss.add(when: 'CONFIG_TERMINAL3270', if_true: files('terminal3270.c'))
 specific_ss.add(when: 'CONFIG_VIRTIO', if_true: files('virtio-serial-bus.c'))
diff --git a/include/hw/char/mchp_pfsoc_mmuart.h b/include/hw/char/mchp_pfsoc_mmuart.h
new file mode 100644
index 0000000..f619902
--- /dev/null
+++ b/include/hw/char/mchp_pfsoc_mmuart.h
@@ -0,0 +1,61 @@
+/*
+ * Microchip PolarFire SoC MMUART emulation
+ *
+ * Copyright (c) 2020 Wind River Systems, Inc.
+ *
+ * Author:
+ *   Bin Meng <bin.meng@windriver.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_MCHP_PFSOC_MMUART_H
+#define HW_MCHP_PFSOC_MMUART_H
+
+#include "hw/char/serial.h"
+
+#define MCHP_PFSOC_MMUART_REG_SIZE  52
+
+typedef struct MchpPfSoCMMUartState {
+    MemoryRegion iomem;
+    hwaddr base;
+    qemu_irq irq;
+
+    SerialMM *serial;
+
+    uint32_t reg[MCHP_PFSOC_MMUART_REG_SIZE / sizeof(uint32_t)];
+} MchpPfSoCMMUartState;
+
+/**
+ * mchp_pfsoc_mmuart_create - Create a Microchip PolarFire SoC MMUART
+ *
+ * This is a helper routine for board to create a MMUART device that is
+ * compatible with Microchip PolarFire SoC.
+ *
+ * @sysmem: system memory region to map
+ * @base: base address of the MMUART registers
+ * @irq: IRQ number of the MMUART device
+ * @chr: character device to associate to
+ *
+ * @return: a pointer to the device specific control structure
+ */
+MchpPfSoCMMUartState *mchp_pfsoc_mmuart_create(MemoryRegion *sysmem,
+    hwaddr base, qemu_irq irq, Chardev *chr);
+
+#endif /* HW_MCHP_PFSOC_MMUART_H */