[Qemu-devel] [PATCH v5 19/30] riscv: sifive: Implement PRCI model for FU540

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

This adds a simple PRCI model for FU540 (sifive_u). It has different
register layout from the existing PRCI model for FE310 (sifive_e).

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

---

Changes in v5:
- change to use defines instead of enums
- change to use qemu_log_mask(LOG_GUEST_ERROR,...) in sifive_u_prci
- creating a 32-bit val variable and using that instead of casting
  everywhere in sifive_u_prci_write()
- move all register initialization to sifive_u_prci_reset() function
- drop sifive_u_prci_create()
- s/codes that worked/code that works/g

Changes in v4:
- prefix all macros/variables/functions with SIFIVE_U/sifive_u
  in the sifive_u_prci driver

Changes in v3: None
Changes in v2: None

 hw/riscv/Makefile.objs           |   1 +
 hw/riscv/sifive_u_prci.c         | 171 +++++++++++++++++++++++++++++++++++++++
 include/hw/riscv/sifive_u_prci.h |  81 +++++++++++++++++++
 3 files changed, 253 insertions(+)
 create mode 100644 hw/riscv/sifive_u_prci.c
 create mode 100644 include/hw/riscv/sifive_u_prci.h

diff --git a/hw/riscv/Makefile.objs b/hw/riscv/Makefile.objs
index c859697..b95bbd5 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-$(CONFIG_SIFIVE_U) += sifive_u_prci.o
 obj-$(CONFIG_SIFIVE) += sifive_uart.o
 obj-$(CONFIG_SPIKE) += spike.o
 obj-$(CONFIG_RISCV_VIRT) += virt.o
diff --git a/hw/riscv/sifive_u_prci.c b/hw/riscv/sifive_u_prci.c
new file mode 100644
index 0000000..c6438fb
--- /dev/null
+++ b/hw/riscv/sifive_u_prci.c
@@ -0,0 +1,171 @@
+/*
+ * QEMU SiFive U PRCI (Power, Reset, Clock, Interrupt)
+ *
+ * Copyright (c) 2019 Bin Meng <bmeng.cn@gmail.com>
+ *
+ * Simple model of the PRCI 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/log.h"
+#include "qemu/module.h"
+#include "hw/riscv/sifive_u_prci.h"
+
+static uint64_t sifive_u_prci_read(void *opaque, hwaddr addr, unsigned int size)
+{
+    SiFiveUPRCIState *s = opaque;
+
+    switch (addr) {
+    case SIFIVE_U_PRCI_HFXOSCCFG:
+        return s->hfxosccfg;
+    case SIFIVE_U_PRCI_COREPLLCFG0:
+        return s->corepllcfg0;
+    case SIFIVE_U_PRCI_DDRPLLCFG0:
+        return s->ddrpllcfg0;
+    case SIFIVE_U_PRCI_DDRPLLCFG1:
+        return s->ddrpllcfg1;
+    case SIFIVE_U_PRCI_GEMGXLPLLCFG0:
+        return s->gemgxlpllcfg0;
+    case SIFIVE_U_PRCI_GEMGXLPLLCFG1:
+        return s->gemgxlpllcfg1;
+    case SIFIVE_U_PRCI_CORECLKSEL:
+        return s->coreclksel;
+    case SIFIVE_U_PRCI_DEVICESRESET:
+        return s->devicesreset;
+    case SIFIVE_U_PRCI_CLKMUXSTATUS:
+        return s->clkmuxstatus;
+    }
+
+    qemu_log_mask(LOG_GUEST_ERROR, "%s: read: addr=0x%x\n",
+                  __func__, (int)addr);
+
+    return 0;
+}
+
+static void sifive_u_prci_write(void *opaque, hwaddr addr,
+                                uint64_t val64, unsigned int size)
+{
+    SiFiveUPRCIState *s = opaque;
+    uint32_t val32 = (uint32_t)val64;
+
+    switch (addr) {
+    case SIFIVE_U_PRCI_HFXOSCCFG:
+        s->hfxosccfg = val32;
+        /* OSC stays ready */
+        s->hfxosccfg |= SIFIVE_U_PRCI_HFXOSCCFG_RDY;
+        break;
+    case SIFIVE_U_PRCI_COREPLLCFG0:
+        s->corepllcfg0 = val32;
+        /* internal feedback */
+        s->corepllcfg0 |= SIFIVE_U_PRCI_PLLCFG0_FSE;
+        /* PLL stays locked */
+        s->corepllcfg0 |= SIFIVE_U_PRCI_PLLCFG0_LOCK;
+        break;
+    case SIFIVE_U_PRCI_DDRPLLCFG0:
+        s->ddrpllcfg0 = val32;
+        /* internal feedback */
+        s->ddrpllcfg0 |= SIFIVE_U_PRCI_PLLCFG0_FSE;
+        /* PLL stays locked */
+        s->ddrpllcfg0 |= SIFIVE_U_PRCI_PLLCFG0_LOCK;
+        break;
+    case SIFIVE_U_PRCI_DDRPLLCFG1:
+        s->ddrpllcfg1 = val32;
+        break;
+    case SIFIVE_U_PRCI_GEMGXLPLLCFG0:
+        s->gemgxlpllcfg0 = val32;
+         /* internal feedback */
+        s->gemgxlpllcfg0 |= SIFIVE_U_PRCI_PLLCFG0_FSE;
+       /* PLL stays locked */
+        s->gemgxlpllcfg0 |= SIFIVE_U_PRCI_PLLCFG0_LOCK;
+        break;
+    case SIFIVE_U_PRCI_GEMGXLPLLCFG1:
+        s->gemgxlpllcfg1 = val32;
+        break;
+    case SIFIVE_U_PRCI_CORECLKSEL:
+        s->coreclksel = val32;
+        break;
+    case SIFIVE_U_PRCI_DEVICESRESET:
+        s->devicesreset = val32;
+        break;
+    case SIFIVE_U_PRCI_CLKMUXSTATUS:
+        s->clkmuxstatus = val32;
+        break;
+    default:
+        qemu_log_mask(LOG_GUEST_ERROR, "%s: bad write: addr=0x%x v=0x%x\n",
+                      __func__, (int)addr, (int)val64);
+    }
+}
+
+static const MemoryRegionOps sifive_u_prci_ops = {
+    .read = sifive_u_prci_read,
+    .write = sifive_u_prci_write,
+    .endianness = DEVICE_NATIVE_ENDIAN,
+    .valid = {
+        .min_access_size = 4,
+        .max_access_size = 4
+    }
+};
+
+static void sifive_u_prci_realize(DeviceState *dev, Error **errp)
+{
+    SiFiveUPRCIState *s = SIFIVE_U_PRCI(dev);
+
+    memory_region_init_io(&s->mmio, OBJECT(dev), &sifive_u_prci_ops, s,
+                          TYPE_SIFIVE_U_PRCI, SIFIVE_U_PRCI_REG_SIZE);
+    sysbus_init_mmio(SYS_BUS_DEVICE(dev), &s->mmio);
+}
+
+static void sifive_u_prci_reset(DeviceState *dev)
+{
+    SiFiveUPRCIState *s = SIFIVE_U_PRCI(dev);
+
+    /* Initialize register to power-on-reset values */
+    s->hfxosccfg = (SIFIVE_U_PRCI_HFXOSCCFG_RDY | SIFIVE_U_PRCI_HFXOSCCFG_EN);
+    s->corepllcfg0 = (SIFIVE_U_PRCI_PLLCFG0_DIVR | SIFIVE_U_PRCI_PLLCFG0_DIVF |
+                      SIFIVE_U_PRCI_PLLCFG0_DIVQ | SIFIVE_U_PRCI_PLLCFG0_FSE |
+                      SIFIVE_U_PRCI_PLLCFG0_LOCK);
+    s->ddrpllcfg0 = (SIFIVE_U_PRCI_PLLCFG0_DIVR | SIFIVE_U_PRCI_PLLCFG0_DIVF |
+                     SIFIVE_U_PRCI_PLLCFG0_DIVQ | SIFIVE_U_PRCI_PLLCFG0_FSE |
+                     SIFIVE_U_PRCI_PLLCFG0_LOCK);
+    s->gemgxlpllcfg0 = (SIFIVE_U_PRCI_PLLCFG0_DIVR |
+                        SIFIVE_U_PRCI_PLLCFG0_DIVF |
+                        SIFIVE_U_PRCI_PLLCFG0_DIVQ |
+                        SIFIVE_U_PRCI_PLLCFG0_FSE |
+                        SIFIVE_U_PRCI_PLLCFG0_LOCK);
+    s->coreclksel = SIFIVE_U_PRCI_CORECLKSEL_HFCLK;
+}
+
+static void sifive_u_prci_class_init(ObjectClass *klass, void *data)
+{
+    DeviceClass *dc = DEVICE_CLASS(klass);
+
+    dc->realize = sifive_u_prci_realize;
+    dc->reset = sifive_u_prci_reset;
+}
+
+static const TypeInfo sifive_u_prci_info = {
+    .name          = TYPE_SIFIVE_U_PRCI,
+    .parent        = TYPE_SYS_BUS_DEVICE,
+    .instance_size = sizeof(SiFiveUPRCIState),
+    .class_init    = sifive_u_prci_class_init,
+};
+
+static void sifive_u_prci_register_types(void)
+{
+    type_register_static(&sifive_u_prci_info);
+}
+
+type_init(sifive_u_prci_register_types)
diff --git a/include/hw/riscv/sifive_u_prci.h b/include/hw/riscv/sifive_u_prci.h
new file mode 100644
index 0000000..60a2eab
--- /dev/null
+++ b/include/hw/riscv/sifive_u_prci.h
@@ -0,0 +1,81 @@
+/*
+ * QEMU SiFive U PRCI (Power, Reset, Clock, Interrupt) 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_PRCI_H
+#define HW_SIFIVE_U_PRCI_H
+
+#define SIFIVE_U_PRCI_HFXOSCCFG     0x00
+#define SIFIVE_U_PRCI_COREPLLCFG0   0x04
+#define SIFIVE_U_PRCI_DDRPLLCFG0    0x0C
+#define SIFIVE_U_PRCI_DDRPLLCFG1    0x10
+#define SIFIVE_U_PRCI_GEMGXLPLLCFG0 0x1C
+#define SIFIVE_U_PRCI_GEMGXLPLLCFG1 0x20
+#define SIFIVE_U_PRCI_CORECLKSEL    0x24
+#define SIFIVE_U_PRCI_DEVICESRESET  0x28
+#define SIFIVE_U_PRCI_CLKMUXSTATUS  0x2C
+
+/*
+ * Current FU540-C000 manual says ready bit is at bit 29, but
+ * freedom-u540-c000-bootloader codes (ux00prci.h) says it is at bit 31.
+ * We have to trust the actual code that works.
+ *
+ * see https://github.com/sifive/freedom-u540-c000-bootloader
+ */
+
+#define SIFIVE_U_PRCI_HFXOSCCFG_EN  (1 << 30)
+#define SIFIVE_U_PRCI_HFXOSCCFG_RDY (1 << 31)
+
+/* xxxPLLCFG0 register bits */
+#define SIFIVE_U_PRCI_PLLCFG0_DIVR  (1 << 0)
+#define SIFIVE_U_PRCI_PLLCFG0_DIVF  (31 << 6)
+#define SIFIVE_U_PRCI_PLLCFG0_DIVQ  (3 << 15)
+#define SIFIVE_U_PRCI_PLLCFG0_FSE   (1 << 25)
+#define SIFIVE_U_PRCI_PLLCFG0_LOCK  (1 << 31)
+
+/* xxxPLLCFG1 register bits */
+#define SIFIVE_U_PRCI_PLLCFG1_CKE   (1 << 24)
+
+/* coreclksel register bits */
+#define SIFIVE_U_PRCI_CORECLKSEL_HFCLK  (1 << 0)
+
+
+#define SIFIVE_U_PRCI_REG_SIZE  0x1000
+
+#define TYPE_SIFIVE_U_PRCI      "riscv.sifive.u.prci"
+
+#define SIFIVE_U_PRCI(obj) \
+    OBJECT_CHECK(SiFiveUPRCIState, (obj), TYPE_SIFIVE_U_PRCI)
+
+typedef struct SiFiveUPRCIState {
+    /*< private >*/
+    SysBusDevice parent_obj;
+
+    /*< public >*/
+    MemoryRegion mmio;
+    uint32_t hfxosccfg;
+    uint32_t corepllcfg0;
+    uint32_t ddrpllcfg0;
+    uint32_t ddrpllcfg1;
+    uint32_t gemgxlpllcfg0;
+    uint32_t gemgxlpllcfg1;
+    uint32_t coreclksel;
+    uint32_t devicesreset;
+    uint32_t clkmuxstatus;
+} SiFiveUPRCIState;
+
+#endif /* HW_SIFIVE_U_PRCI_H */
-- 
2.7.4