hw: arm: allwinner-sramc: Add SRAM Controller support for R40

Only a few important registers are added, especially the SRAM_VER
register.

Signed-off-by: qianfan Zhao <qianfanguijin@163.com>
Reviewed-by: Niek Linnenbank <nieklinnenbank@gmail.com>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

4 files changed, 192 insertions, 0 deletions

diff --git a/hw/misc/Kconfig b/hw/misc/Kconfig
index efeb430a6c..e4c2149175 100644
--- a/hw/misc/Kconfig
+++ b/hw/misc/Kconfig
@@ -170,6 +170,9 @@ config VIRT_CTRL
 config LASI
     bool
 
+config ALLWINNER_SRAMC
+    bool
+
 config ALLWINNER_A10_CCM
     bool
 
diff --git a/hw/misc/allwinner-sramc.c b/hw/misc/allwinner-sramc.c
new file mode 100644
index 0000000000..a8b731f8f2
--- /dev/null
+++ b/hw/misc/allwinner-sramc.c
@@ -0,0 +1,184 @@
+/*
+ * Allwinner R40 SRAM controller emulation
+ *
+ * Copyright (C) 2023 qianfan Zhao <qianfanguijin@163.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 "qapi/error.h"
+#include "hw/qdev-properties.h"
+#include "hw/qdev-properties-system.h"
+#include "hw/misc/allwinner-sramc.h"
+#include "trace.h"
+
+/*
+ * register offsets
+ * https://linux-sunxi.org/SRAM_Controller_Register_Guide
+ */
+enum {
+    REG_SRAM_CTL1_CFG               = 0x04, /* SRAM Control register 1 */
+    REG_SRAM_VER                    = 0x24, /* SRAM Version register */
+    REG_SRAM_R40_SOFT_ENTRY_REG0    = 0xbc,
+};
+
+/* REG_SRAMC_VERSION bit defines */
+#define SRAM_VER_READ_ENABLE            (1 << 15)
+#define SRAM_VER_VERSION_SHIFT          16
+#define SRAM_VERSION_SUN8I_R40          0x1701
+
+static uint64_t allwinner_sramc_read(void *opaque, hwaddr offset,
+                                     unsigned size)
+{
+    AwSRAMCState *s = AW_SRAMC(opaque);
+    AwSRAMCClass *sc = AW_SRAMC_GET_CLASS(s);
+    uint64_t val = 0;
+
+    switch (offset) {
+    case REG_SRAM_CTL1_CFG:
+        val = s->sram_ctl1;
+        break;
+    case REG_SRAM_VER:
+        /* bit15: lock bit, set this bit before reading this register */
+        if (s->sram_ver & SRAM_VER_READ_ENABLE) {
+            val = SRAM_VER_READ_ENABLE |
+                    (sc->sram_version_code << SRAM_VER_VERSION_SHIFT);
+        }
+        break;
+    case REG_SRAM_R40_SOFT_ENTRY_REG0:
+        val = s->sram_soft_entry_reg0;
+        break;
+    default:
+        qemu_log_mask(LOG_GUEST_ERROR, "%s: out-of-bounds offset 0x%04x\n",
+                      __func__, (uint32_t)offset);
+        return 0;
+    }
+
+    trace_allwinner_sramc_read(offset, val);
+
+    return val;
+}
+
+static void allwinner_sramc_write(void *opaque, hwaddr offset,
+                                  uint64_t val, unsigned size)
+{
+    AwSRAMCState *s = AW_SRAMC(opaque);
+
+    trace_allwinner_sramc_write(offset, val);
+
+    switch (offset) {
+    case REG_SRAM_CTL1_CFG:
+        s->sram_ctl1 = val;
+        break;
+    case REG_SRAM_VER:
+        /* Only the READ_ENABLE bit is writeable */
+        s->sram_ver = val & SRAM_VER_READ_ENABLE;
+        break;
+    case REG_SRAM_R40_SOFT_ENTRY_REG0:
+        s->sram_soft_entry_reg0 = val;
+        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_sramc_ops = {
+    .read = allwinner_sramc_read,
+    .write = allwinner_sramc_write,
+    .endianness = DEVICE_NATIVE_ENDIAN,
+    .valid = {
+        .min_access_size = 4,
+        .max_access_size = 4,
+    },
+    .impl.min_access_size = 4,
+};
+
+static const VMStateDescription allwinner_sramc_vmstate = {
+    .name = "allwinner-sramc",
+    .version_id = 1,
+    .minimum_version_id = 1,
+    .fields = (VMStateField[]) {
+        VMSTATE_UINT32(sram_ver, AwSRAMCState),
+        VMSTATE_UINT32(sram_soft_entry_reg0, AwSRAMCState),
+        VMSTATE_END_OF_LIST()
+    }
+};
+
+static void allwinner_sramc_reset(DeviceState *dev)
+{
+    AwSRAMCState *s = AW_SRAMC(dev);
+    AwSRAMCClass *sc = AW_SRAMC_GET_CLASS(s);
+
+    switch (sc->sram_version_code) {
+    case SRAM_VERSION_SUN8I_R40:
+        s->sram_ctl1 = 0x1300;
+        break;
+    }
+}
+
+static void allwinner_sramc_class_init(ObjectClass *klass, void *data)
+{
+    DeviceClass *dc = DEVICE_CLASS(klass);
+
+    dc->reset = allwinner_sramc_reset;
+    dc->vmsd = &allwinner_sramc_vmstate;
+}
+
+static void allwinner_sramc_init(Object *obj)
+{
+    SysBusDevice *sbd = SYS_BUS_DEVICE(obj);
+    AwSRAMCState *s = AW_SRAMC(obj);
+
+    /* Memory mapping */
+    memory_region_init_io(&s->iomem, OBJECT(s), &allwinner_sramc_ops, s,
+                           TYPE_AW_SRAMC, 1 * KiB);
+    sysbus_init_mmio(sbd, &s->iomem);
+}
+
+static const TypeInfo allwinner_sramc_info = {
+    .name          = TYPE_AW_SRAMC,
+    .parent        = TYPE_SYS_BUS_DEVICE,
+    .instance_init = allwinner_sramc_init,
+    .instance_size = sizeof(AwSRAMCState),
+    .class_init    = allwinner_sramc_class_init,
+};
+
+static void allwinner_r40_sramc_class_init(ObjectClass *klass, void *data)
+{
+    AwSRAMCClass *sc = AW_SRAMC_CLASS(klass);
+
+    sc->sram_version_code = SRAM_VERSION_SUN8I_R40;
+}
+
+static const TypeInfo allwinner_r40_sramc_info = {
+    .name          = TYPE_AW_SRAMC_SUN8I_R40,
+    .parent        = TYPE_AW_SRAMC,
+    .class_init    = allwinner_r40_sramc_class_init,
+};
+
+static void allwinner_sramc_register(void)
+{
+    type_register_static(&allwinner_sramc_info);
+    type_register_static(&allwinner_r40_sramc_info);
+}
+
+type_init(allwinner_sramc_register)
diff --git a/hw/misc/meson.build b/hw/misc/meson.build
index b04d43e05a..78ca857c9d 100644
--- a/hw/misc/meson.build
+++ b/hw/misc/meson.build
@@ -37,6 +37,7 @@ subdir('macio')
 
 softmmu_ss.add(when: 'CONFIG_IVSHMEM_DEVICE', if_true: files('ivshmem.c'))
 
+softmmu_ss.add(when: 'CONFIG_ALLWINNER_SRAMC', if_true: files('allwinner-sramc.c'))
 softmmu_ss.add(when: 'CONFIG_ALLWINNER_A10_CCM', if_true: files('allwinner-a10-ccm.c'))
 softmmu_ss.add(when: 'CONFIG_ALLWINNER_A10_DRAMC', if_true: files('allwinner-a10-dramc.c'))
 softmmu_ss.add(when: 'CONFIG_ALLWINNER_H3', if_true: files('allwinner-h3-ccu.c'))
diff --git a/hw/misc/trace-events b/hw/misc/trace-events
index 8b68f07765..4d1a0e17af 100644
--- a/hw/misc/trace-events
+++ b/hw/misc/trace-events
@@ -33,6 +33,10 @@ allwinner_r40_dramphy_write(uint64_t offset, uint64_t data, unsigned size) "writ
 allwinner_sid_read(uint64_t offset, uint64_t data, unsigned size) "offset 0x%" PRIx64 " data 0x%" PRIx64 " size %" PRIu32
 allwinner_sid_write(uint64_t offset, uint64_t data, unsigned size) "offset 0x%" PRIx64 " data 0x%" PRIx64 " size %" PRIu32
 
+# allwinner-sramc.c
+allwinner_sramc_read(uint64_t offset, uint64_t data) "offset 0x%" PRIx64 " data 0x%" PRIx64
+allwinner_sramc_write(uint64_t offset, uint64_t data) "offset 0x%" PRIx64 " data 0x%" PRIx64
+
 # avr_power.c
 avr_power_read(uint8_t value) "power_reduc read value:%u"
 avr_power_write(uint8_t value) "power_reduc write value:%u"