hw/arm/allwinner: add CPU Configuration module

Various Allwinner System on Chip designs contain multiple processors
that can be configured and reset using the generic CPU Configuration
module interface. This commit adds support for the Allwinner CPU
configuration interface which emulates the following features:

 * CPU reset
 * CPU status

Signed-off-by: Niek Linnenbank <nieklinnenbank@gmail.com>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Message-id: 20200311221854.30370-7-nieklinnenbank@gmail.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

3 files changed, 288 insertions, 0 deletions

diff --git a/hw/misc/Makefile.objs b/hw/misc/Makefile.objs
index 63b2e528f9..f3788a5903 100644
--- a/hw/misc/Makefile.objs
+++ b/hw/misc/Makefile.objs
@@ -29,6 +29,7 @@ common-obj-$(CONFIG_MACIO) += macio/
 common-obj-$(CONFIG_IVSHMEM_DEVICE) += ivshmem.o
 
 common-obj-$(CONFIG_ALLWINNER_H3) += allwinner-h3-ccu.o
+obj-$(CONFIG_ALLWINNER_H3) += allwinner-cpucfg.o
 common-obj-$(CONFIG_ALLWINNER_H3) += allwinner-h3-sysctrl.o
 common-obj-$(CONFIG_REALVIEW) += arm_sysctl.o
 common-obj-$(CONFIG_NSERIES) += cbus.o
diff --git a/hw/misc/allwinner-cpucfg.c b/hw/misc/allwinner-cpucfg.c
new file mode 100644
index 0000000000..bbd33a7dac
--- /dev/null
+++ b/hw/misc/allwinner-cpucfg.c
@@ -0,0 +1,282 @@
+/*
+ * Allwinner CPU Configuration Module emulation
+ *
+ * Copyright (C) 2019 Niek Linnenbank <nieklinnenbank@gmail.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 of the License, or
+ * (at your option) any later version.
+ *
+ * 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/units.h"
+#include "hw/sysbus.h"
+#include "migration/vmstate.h"
+#include "qemu/log.h"
+#include "qemu/module.h"
+#include "qemu/error-report.h"
+#include "qemu/timer.h"
+#include "hw/core/cpu.h"
+#include "target/arm/arm-powerctl.h"
+#include "target/arm/cpu.h"
+#include "hw/misc/allwinner-cpucfg.h"
+#include "trace.h"
+
+/* CPUCFG register offsets */
+enum {
+    REG_CPUS_RST_CTRL       = 0x0000, /* CPUs Reset Control */
+    REG_CPU0_RST_CTRL       = 0x0040, /* CPU#0 Reset Control */
+    REG_CPU0_CTRL           = 0x0044, /* CPU#0 Control */
+    REG_CPU0_STATUS         = 0x0048, /* CPU#0 Status */
+    REG_CPU1_RST_CTRL       = 0x0080, /* CPU#1 Reset Control */
+    REG_CPU1_CTRL           = 0x0084, /* CPU#1 Control */
+    REG_CPU1_STATUS         = 0x0088, /* CPU#1 Status */
+    REG_CPU2_RST_CTRL       = 0x00C0, /* CPU#2 Reset Control */
+    REG_CPU2_CTRL           = 0x00C4, /* CPU#2 Control */
+    REG_CPU2_STATUS         = 0x00C8, /* CPU#2 Status */
+    REG_CPU3_RST_CTRL       = 0x0100, /* CPU#3 Reset Control */
+    REG_CPU3_CTRL           = 0x0104, /* CPU#3 Control */
+    REG_CPU3_STATUS         = 0x0108, /* CPU#3 Status */
+    REG_CPU_SYS_RST         = 0x0140, /* CPU System Reset */
+    REG_CLK_GATING          = 0x0144, /* CPU Clock Gating */
+    REG_GEN_CTRL            = 0x0184, /* General Control */
+    REG_SUPER_STANDBY       = 0x01A0, /* Super Standby Flag */
+    REG_ENTRY_ADDR          = 0x01A4, /* Reset Entry Address */
+    REG_DBG_EXTERN          = 0x01E4, /* Debug External */
+    REG_CNT64_CTRL          = 0x0280, /* 64-bit Counter Control */
+    REG_CNT64_LOW           = 0x0284, /* 64-bit Counter Low */
+    REG_CNT64_HIGH          = 0x0288, /* 64-bit Counter High */
+};
+
+/* CPUCFG register flags */
+enum {
+    CPUX_RESET_RELEASED     = ((1 << 1) | (1 << 0)),
+    CPUX_STATUS_SMP         = (1 << 0),
+    CPU_SYS_RESET_RELEASED  = (1 << 0),
+    CLK_GATING_ENABLE       = ((1 << 8) | 0xF),
+};
+
+/* CPUCFG register reset values */
+enum {
+    REG_CLK_GATING_RST      = 0x0000010F,
+    REG_GEN_CTRL_RST        = 0x00000020,
+    REG_SUPER_STANDBY_RST   = 0x0,
+    REG_CNT64_CTRL_RST      = 0x0,
+};
+
+/* CPUCFG constants */
+enum {
+    CPU_EXCEPTION_LEVEL_ON_RESET = 3, /* EL3 */
+};
+
+static void allwinner_cpucfg_cpu_reset(AwCpuCfgState *s, uint8_t cpu_id)
+{
+    int ret;
+
+    trace_allwinner_cpucfg_cpu_reset(cpu_id, s->entry_addr);
+
+    ARMCPU *target_cpu = ARM_CPU(arm_get_cpu_by_id(cpu_id));
+    if (!target_cpu) {
+        /*
+         * Called with a bogus value for cpu_id. Guest error will
+         * already have been logged, we can simply return here.
+         */
+        return;
+    }
+    bool target_aa64 = arm_feature(&target_cpu->env, ARM_FEATURE_AARCH64);
+
+    ret = arm_set_cpu_on(cpu_id, s->entry_addr, 0,
+                         CPU_EXCEPTION_LEVEL_ON_RESET, target_aa64);
+    if (ret != QEMU_ARM_POWERCTL_RET_SUCCESS) {
+        error_report("%s: failed to bring up CPU %d: err %d",
+                     __func__, cpu_id, ret);
+        return;
+    }
+}
+
+static uint64_t allwinner_cpucfg_read(void *opaque, hwaddr offset,
+                                      unsigned size)
+{
+    const AwCpuCfgState *s = AW_CPUCFG(opaque);
+    uint64_t val = 0;
+
+    switch (offset) {
+    case REG_CPUS_RST_CTRL:     /* CPUs Reset Control */
+    case REG_CPU_SYS_RST:       /* CPU System Reset */
+        val = CPU_SYS_RESET_RELEASED;
+        break;
+    case REG_CPU0_RST_CTRL:     /* CPU#0 Reset Control */
+    case REG_CPU1_RST_CTRL:     /* CPU#1 Reset Control */
+    case REG_CPU2_RST_CTRL:     /* CPU#2 Reset Control */
+    case REG_CPU3_RST_CTRL:     /* CPU#3 Reset Control */
+        val = CPUX_RESET_RELEASED;
+        break;
+    case REG_CPU0_CTRL:         /* CPU#0 Control */
+    case REG_CPU1_CTRL:         /* CPU#1 Control */
+    case REG_CPU2_CTRL:         /* CPU#2 Control */
+    case REG_CPU3_CTRL:         /* CPU#3 Control */
+        val = 0;
+        break;
+    case REG_CPU0_STATUS:       /* CPU#0 Status */
+    case REG_CPU1_STATUS:       /* CPU#1 Status */
+    case REG_CPU2_STATUS:       /* CPU#2 Status */
+    case REG_CPU3_STATUS:       /* CPU#3 Status */
+        val = CPUX_STATUS_SMP;
+        break;
+    case REG_CLK_GATING:        /* CPU Clock Gating */
+        val = CLK_GATING_ENABLE;
+        break;
+    case REG_GEN_CTRL:          /* General Control */
+        val = s->gen_ctrl;
+        break;
+    case REG_SUPER_STANDBY:     /* Super Standby Flag */
+        val = s->super_standby;
+        break;
+    case REG_ENTRY_ADDR:        /* Reset Entry Address */
+        val = s->entry_addr;
+        break;
+    case REG_DBG_EXTERN:        /* Debug External */
+    case REG_CNT64_CTRL:        /* 64-bit Counter Control */
+    case REG_CNT64_LOW:         /* 64-bit Counter Low */
+    case REG_CNT64_HIGH:        /* 64-bit Counter High */
+        qemu_log_mask(LOG_UNIMP, "%s: unimplemented register at 0x%04x\n",
+                      __func__, (uint32_t)offset);
+        break;
+    default:
+        qemu_log_mask(LOG_GUEST_ERROR, "%s: out-of-bounds offset 0x%04x\n",
+                      __func__, (uint32_t)offset);
+        break;
+    }
+
+    trace_allwinner_cpucfg_read(offset, val, size);
+
+    return val;
+}
+
+static void allwinner_cpucfg_write(void *opaque, hwaddr offset,
+                                   uint64_t val, unsigned size)
+{
+    AwCpuCfgState *s = AW_CPUCFG(opaque);
+
+    trace_allwinner_cpucfg_write(offset, val, size);
+
+    switch (offset) {
+    case REG_CPUS_RST_CTRL:     /* CPUs Reset Control */
+    case REG_CPU_SYS_RST:       /* CPU System Reset */
+        break;
+    case REG_CPU0_RST_CTRL:     /* CPU#0 Reset Control */
+    case REG_CPU1_RST_CTRL:     /* CPU#1 Reset Control */
+    case REG_CPU2_RST_CTRL:     /* CPU#2 Reset Control */
+    case REG_CPU3_RST_CTRL:     /* CPU#3 Reset Control */
+        if (val) {
+            allwinner_cpucfg_cpu_reset(s, (offset - REG_CPU0_RST_CTRL) >> 6);
+        }
+        break;
+    case REG_CPU0_CTRL:         /* CPU#0 Control */
+    case REG_CPU1_CTRL:         /* CPU#1 Control */
+    case REG_CPU2_CTRL:         /* CPU#2 Control */
+    case REG_CPU3_CTRL:         /* CPU#3 Control */
+    case REG_CPU0_STATUS:       /* CPU#0 Status */
+    case REG_CPU1_STATUS:       /* CPU#1 Status */
+    case REG_CPU2_STATUS:       /* CPU#2 Status */
+    case REG_CPU3_STATUS:       /* CPU#3 Status */
+    case REG_CLK_GATING:        /* CPU Clock Gating */
+        break;
+    case REG_GEN_CTRL:          /* General Control */
+        s->gen_ctrl = val;
+        break;
+    case REG_SUPER_STANDBY:     /* Super Standby Flag */
+        s->super_standby = val;
+        break;
+    case REG_ENTRY_ADDR:        /* Reset Entry Address */
+        s->entry_addr = val;
+        break;
+    case REG_DBG_EXTERN:        /* Debug External */
+    case REG_CNT64_CTRL:        /* 64-bit Counter Control */
+    case REG_CNT64_LOW:         /* 64-bit Counter Low */
+    case REG_CNT64_HIGH:        /* 64-bit Counter High */
+        qemu_log_mask(LOG_UNIMP, "%s: unimplemented register at 0x%04x\n",
+                      __func__, (uint32_t)offset);
+        break;
+    default:
+        qemu_log_mask(LOG_GUEST_ERROR, "%s: out-of-bounds offset 0x%04x\n",
+                      __func__, (uint32_t)offset);
+        break;
+    }
+}
+
+static const MemoryRegionOps allwinner_cpucfg_ops = {
+    .read = allwinner_cpucfg_read,
+    .write = allwinner_cpucfg_write,
+    .endianness = DEVICE_NATIVE_ENDIAN,
+    .valid = {
+        .min_access_size = 4,
+        .max_access_size = 4,
+    },
+    .impl.min_access_size = 4,
+};
+
+static void allwinner_cpucfg_reset(DeviceState *dev)
+{
+    AwCpuCfgState *s = AW_CPUCFG(dev);
+
+    /* Set default values for registers */
+    s->gen_ctrl = REG_GEN_CTRL_RST;
+    s->super_standby = REG_SUPER_STANDBY_RST;
+    s->entry_addr = 0;
+}
+
+static void allwinner_cpucfg_init(Object *obj)
+{
+    SysBusDevice *sbd = SYS_BUS_DEVICE(obj);
+    AwCpuCfgState *s = AW_CPUCFG(obj);
+
+    /* Memory mapping */
+    memory_region_init_io(&s->iomem, OBJECT(s), &allwinner_cpucfg_ops, s,
+                          TYPE_AW_CPUCFG, 1 * KiB);
+    sysbus_init_mmio(sbd, &s->iomem);
+}
+
+static const VMStateDescription allwinner_cpucfg_vmstate = {
+    .name = "allwinner-cpucfg",
+    .version_id = 1,
+    .minimum_version_id = 1,
+    .fields = (VMStateField[]) {
+        VMSTATE_UINT32(gen_ctrl, AwCpuCfgState),
+        VMSTATE_UINT32(super_standby, AwCpuCfgState),
+        VMSTATE_UINT32(entry_addr, AwCpuCfgState),
+        VMSTATE_END_OF_LIST()
+    }
+};
+
+static void allwinner_cpucfg_class_init(ObjectClass *klass, void *data)
+{
+    DeviceClass *dc = DEVICE_CLASS(klass);
+
+    dc->reset = allwinner_cpucfg_reset;
+    dc->vmsd = &allwinner_cpucfg_vmstate;
+}
+
+static const TypeInfo allwinner_cpucfg_info = {
+    .name          = TYPE_AW_CPUCFG,
+    .parent        = TYPE_SYS_BUS_DEVICE,
+    .instance_init = allwinner_cpucfg_init,
+    .instance_size = sizeof(AwCpuCfgState),
+    .class_init    = allwinner_cpucfg_class_init,
+};
+
+static void allwinner_cpucfg_register(void)
+{
+    type_register_static(&allwinner_cpucfg_info);
+}
+
+type_init(allwinner_cpucfg_register)
diff --git a/hw/misc/trace-events b/hw/misc/trace-events
index 7f0f5dff3a..ede1650672 100644
--- a/hw/misc/trace-events
+++ b/hw/misc/trace-events
@@ -1,5 +1,10 @@
 # See docs/devel/tracing.txt for syntax documentation.
 
+# allwinner-cpucfg.c
+allwinner_cpucfg_cpu_reset(uint8_t cpu_id, uint32_t reset_addr) "id %u, reset_addr 0x%" PRIu32
+allwinner_cpucfg_read(uint64_t offset, uint64_t data, unsigned size) "offset 0x%" PRIx64 " data 0x%" PRIx64 " size %" PRIu32
+allwinner_cpucfg_write(uint64_t offset, uint64_t data, unsigned size) "offset 0x%" PRIx64 " data 0x%" PRIx64 " size %" PRIu32
+
 # eccmemctl.c
 ecc_mem_writel_mer(uint32_t val) "Write memory enable 0x%08x"
 ecc_mem_writel_mdr(uint32_t val) "Write memory delay 0x%08x"