[Qemu-devel] [PATCH v2 18/28] riscv: hw: Implement a model for SiFive FU540 OTP

[Bin Meng <bmeng.cn@gmail.com>]

This implements a simple model for SiFive FU540 OTP (One-Time
Programmable) Memory interface, primarily for reading out the
stored serial number from the first 1 KiB of the 16 KiB OTP
memory reserved by SiFive for internal use.

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
---

Changes in v2: None

 hw/riscv/Makefile.objs          |   1 +
 hw/riscv/sifive_u_otp.c         | 194 ++++++++++++++++++++++++++++++++++++++++
 include/hw/riscv/sifive_u_otp.h |  90 +++++++++++++++++++
 3 files changed, 285 insertions(+)
 create mode 100644 hw/riscv/sifive_u_otp.c
 create mode 100644 include/hw/riscv/sifive_u_otp.h

diff --git a/hw/riscv/Makefile.objs b/hw/riscv/Makefile.objs
index b95bbd5..fc3c6dd 100644
--- a/hw/riscv/Makefile.objs
+++ b/hw/riscv/Makefile.objs
@@ -8,6 +8,7 @@ obj-$(CONFIG_SIFIVE) += sifive_gpio.o
 obj-$(CONFIG_SIFIVE) += sifive_plic.o
 obj-$(CONFIG_SIFIVE) += sifive_test.o
 obj-$(CONFIG_SIFIVE_U) += sifive_u.o
+obj-$(CONFIG_SIFIVE_U) += sifive_u_otp.o
 obj-$(CONFIG_SIFIVE_U) += sifive_u_prci.o
 obj-$(CONFIG_SIFIVE) += sifive_uart.o
 obj-$(CONFIG_SPIKE) += spike.o
diff --git a/hw/riscv/sifive_u_otp.c b/hw/riscv/sifive_u_otp.c
new file mode 100644
index 0000000..f21d9f4
--- /dev/null
+++ b/hw/riscv/sifive_u_otp.c
@@ -0,0 +1,194 @@
+/*
+ * QEMU SiFive U OTP (One-Time Programmable) Memory interface
+ *
+ * Copyright (c) 2019 Bin Meng <bmeng.cn@gmail.com>
+ *
+ * Simple model of the OTP to emulate register reads made by the SDK BSP
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2 or later, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope 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 "hw/sysbus.h"
+#include "qemu/module.h"
+#include "target/riscv/cpu.h"
+#include "hw/riscv/sifive_u_otp.h"
+
+static uint64_t sifive_otp_read(void *opaque, hwaddr addr, unsigned int size)
+{
+    SiFiveOTPState *s = opaque;
+
+    switch (addr) {
+    case SIFIVE_OTP_PA:
+        return s->pa;
+    case SIFIVE_OTP_PAIO:
+        return s->paio;
+    case SIFIVE_OTP_PAS:
+        return s->pas;
+    case SIFIVE_OTP_PCE:
+        return s->pce;
+    case SIFIVE_OTP_PCLK:
+        return s->pclk;
+    case SIFIVE_OTP_PDIN:
+        return s->pdin;
+    case SIFIVE_OTP_PDOUT:
+        if ((s->pce & SIFIVE_OTP_PCE_EN) &&
+            (s->pdstb & SIFIVE_OTP_PDSTB_EN) &&
+            (s->ptrim & SIFIVE_OTP_PTRIM_EN)) {
+            return s->fuse[s->pa & SIFIVE_OTP_PA_MASK];
+        } else {
+            return 0xff;
+        }
+    case SIFIVE_OTP_PDSTB:
+        return s->pdstb;
+    case SIFIVE_OTP_PPROG:
+        return s->pprog;
+    case SIFIVE_OTP_PTC:
+        return s->ptc;
+    case SIFIVE_OTP_PTM:
+        return s->ptm;
+    case SIFIVE_OTP_PTM_REP:
+        return s->ptm_rep;
+    case SIFIVE_OTP_PTR:
+        return s->ptr;
+    case SIFIVE_OTP_PTRIM:
+        return s->ptrim;
+    case SIFIVE_OTP_PWE:
+        return s->pwe;
+    }
+
+    hw_error("%s: read: addr=0x%x\n", __func__, (int)addr);
+    return 0;
+}
+
+static void sifive_otp_write(void *opaque, hwaddr addr,
+                             uint64_t val64, unsigned int size)
+{
+    SiFiveOTPState *s = opaque;
+
+    switch (addr) {
+    case SIFIVE_OTP_PA:
+        s->pa = (uint32_t) val64 & SIFIVE_OTP_PA_MASK;
+        break;
+    case SIFIVE_OTP_PAIO:
+        s->paio = (uint32_t) val64;
+        break;
+    case SIFIVE_OTP_PAS:
+        s->pas = (uint32_t) val64;
+        break;
+    case SIFIVE_OTP_PCE:
+        s->pce = (uint32_t) val64;
+        break;
+    case SIFIVE_OTP_PCLK:
+        s->pclk = (uint32_t) val64;
+        break;
+    case SIFIVE_OTP_PDIN:
+        s->pdin = (uint32_t) val64;
+        break;
+    case SIFIVE_OTP_PDOUT:
+        /* read-only */
+        break;
+    case SIFIVE_OTP_PDSTB:
+        s->pdstb = (uint32_t) val64;
+        break;
+    case SIFIVE_OTP_PPROG:
+        s->pprog = (uint32_t) val64;
+        break;
+    case SIFIVE_OTP_PTC:
+        s->ptc = (uint32_t) val64;
+        break;
+    case SIFIVE_OTP_PTM:
+        s->ptm = (uint32_t) val64;
+        break;
+    case SIFIVE_OTP_PTM_REP:
+        s->ptm_rep = (uint32_t) val64;
+        break;
+    case SIFIVE_OTP_PTR:
+        s->ptr = (uint32_t) val64;
+        break;
+    case SIFIVE_OTP_PTRIM:
+        s->ptrim = (uint32_t) val64;
+        break;
+    case SIFIVE_OTP_PWE:
+        s->pwe = (uint32_t) val64;
+        break;
+    default:
+        hw_error("%s: bad write: addr=0x%x v=0x%x\n",
+                 __func__, (int)addr, (int)val64);
+    }
+}
+
+static const MemoryRegionOps sifive_otp_ops = {
+    .read = sifive_otp_read,
+    .write = sifive_otp_write,
+    .endianness = DEVICE_NATIVE_ENDIAN,
+    .valid = {
+        .min_access_size = 4,
+        .max_access_size = 4
+    }
+};
+
+static Property sifive_otp_properties[] = {
+    DEFINE_PROP_UINT32("serial", SiFiveOTPState, serial, 0),
+    DEFINE_PROP_END_OF_LIST(),
+};
+
+static void sifive_otp_realize(DeviceState *dev, Error **errp)
+{
+    SiFiveOTPState *s = SIFIVE_U_OTP(dev);
+
+    memory_region_init_io(&s->mmio, OBJECT(dev), &sifive_otp_ops, s,
+                          TYPE_SIFIVE_U_OTP, SIFIVE_U_OTP_REG_SIZE);
+    sysbus_init_mmio(SYS_BUS_DEVICE(dev), &s->mmio);
+
+    /* Initialize all fuses' initial value to 0xFFs */
+    memset(s->fuse, 0xff, sizeof(s->fuse));
+
+    /* Make a valid content of serial number */
+    s->fuse[SIFIVE_OTP_SERIAL_ADDR] = s->serial;
+    s->fuse[SIFIVE_OTP_SERIAL_ADDR + 1] = ~(s->serial);
+}
+
+static void sifive_otp_class_init(ObjectClass *klass, void *data)
+{
+    DeviceClass *dc = DEVICE_CLASS(klass);
+
+    dc->props = sifive_otp_properties;
+    dc->realize = sifive_otp_realize;
+}
+
+static const TypeInfo sifive_otp_info = {
+    .name          = TYPE_SIFIVE_U_OTP,
+    .parent        = TYPE_SYS_BUS_DEVICE,
+    .instance_size = sizeof(SiFiveOTPState),
+    .class_init    = sifive_otp_class_init,
+};
+
+static void sifive_otp_register_types(void)
+{
+    type_register_static(&sifive_otp_info);
+}
+
+type_init(sifive_otp_register_types)
+
+
+/* Create OTP device */
+DeviceState *sifive_u_otp_create(hwaddr addr, uint32_t serial)
+{
+    DeviceState *dev = qdev_create(NULL, TYPE_SIFIVE_U_OTP);
+    qdev_prop_set_uint32(dev, "serial", serial);
+    qdev_init_nofail(dev);
+    sysbus_mmio_map(SYS_BUS_DEVICE(dev), 0, addr);
+
+    return dev;
+}
diff --git a/include/hw/riscv/sifive_u_otp.h b/include/hw/riscv/sifive_u_otp.h
new file mode 100644
index 0000000..16095b0
--- /dev/null
+++ b/include/hw/riscv/sifive_u_otp.h
@@ -0,0 +1,90 @@
+/*
+ * QEMU SiFive U OTP (One-Time Programmable) Memory interface
+ *
+ * Copyright (c) 2019 Bin Meng <bmeng.cn@gmail.com>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2 or later, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope 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/>.
+ */
+
+#ifndef HW_SIFIVE_U_OTP_H
+#define HW_SIFIVE_U_OTP_H
+
+enum {
+    SIFIVE_OTP_PA       = 0x00,
+    SIFIVE_OTP_PAIO     = 0x04,
+    SIFIVE_OTP_PAS      = 0x08,
+    SIFIVE_OTP_PCE      = 0x0C,
+    SIFIVE_OTP_PCLK     = 0x10,
+    SIFIVE_OTP_PDIN     = 0x14,
+    SIFIVE_OTP_PDOUT    = 0x18,
+    SIFIVE_OTP_PDSTB    = 0x1C,
+    SIFIVE_OTP_PPROG    = 0x20,
+    SIFIVE_OTP_PTC      = 0x24,
+    SIFIVE_OTP_PTM      = 0x28,
+    SIFIVE_OTP_PTM_REP  = 0x2C,
+    SIFIVE_OTP_PTR      = 0x30,
+    SIFIVE_OTP_PTRIM    = 0x34,
+    SIFIVE_OTP_PWE      = 0x38
+};
+
+enum {
+    SIFIVE_OTP_PCE_EN   = (1 << 0)
+};
+
+enum {
+    SIFIVE_OTP_PDSTB_EN = (1 << 0)
+};
+
+enum {
+    SIFIVE_OTP_PTRIM_EN = (1 << 0)
+};
+
+#define SIFIVE_OTP_PA_MASK      0xfff
+#define SIFIVE_OTP_NUM_FUSES    0x1000
+#define SIFIVE_OTP_SERIAL_ADDR  0xfc
+
+#define SIFIVE_U_OTP_REG_SIZE   0x1000
+
+#define TYPE_SIFIVE_U_OTP       "riscv.sifive.u.otp"
+
+#define SIFIVE_U_OTP(obj) \
+    OBJECT_CHECK(SiFiveOTPState, (obj), TYPE_SIFIVE_U_OTP)
+
+typedef struct SiFiveOTPState {
+    /*< private >*/
+    SysBusDevice parent_obj;
+
+    /*< public >*/
+    MemoryRegion mmio;
+    uint32_t pa;
+    uint32_t paio;
+    uint32_t pas;
+    uint32_t pce;
+    uint32_t pclk;
+    uint32_t pdin;
+    uint32_t pdstb;
+    uint32_t pprog;
+    uint32_t ptc;
+    uint32_t ptm;
+    uint32_t ptm_rep;
+    uint32_t ptr;
+    uint32_t ptrim;
+    uint32_t pwe;
+    uint32_t fuse[SIFIVE_OTP_NUM_FUSES];
+    /* config */
+    uint32_t serial;
+} SiFiveOTPState;
+
+DeviceState *sifive_u_otp_create(hwaddr addr, uint32_t serial);
+
+#endif /* HW_SIFIVE_U_OTP_H */
-- 
2.7.4