[PATCH 10/18] hw/sd: Add Cadence SDHCI emulation

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

From: Bin Meng <bin.meng@windriver.com>

Cadence SD/SDIO/eMMC Host Controller (SD4HC) is an SDHCI compatible
controller. The SDHCI compatible registers start from offset 0x200,
which are called Slot Register Set (SRS) in its datasheet.

This creates a Cadence SDHCI model built on top of the existing
generic SDHCI model. Cadence specific Host Register Set (HRS) is
implemented to make guest software happy.

Signed-off-by: Bin Meng <bin.meng@windriver.com>
---

 hw/sd/Kconfig                 |   4 ++
 hw/sd/Makefile.objs           |   1 +
 hw/sd/cadence_sdhci.c         | 162 ++++++++++++++++++++++++++++++++++++++++++
 include/hw/sd/cadence_sdhci.h |  65 +++++++++++++++++
 4 files changed, 232 insertions(+)
 create mode 100644 hw/sd/cadence_sdhci.c
 create mode 100644 include/hw/sd/cadence_sdhci.h

diff --git a/hw/sd/Kconfig b/hw/sd/Kconfig
index c5e1e55..633b9af 100644
--- a/hw/sd/Kconfig
+++ b/hw/sd/Kconfig
@@ -19,3 +19,7 @@ config SDHCI_PCI
     default y if PCI_DEVICES
     depends on PCI
     select SDHCI
+
+config CADENCE_SDHCI
+    bool
+    select SDHCI
diff --git a/hw/sd/Makefile.objs b/hw/sd/Makefile.objs
index 0d1df17..4d500a6 100644
--- a/hw/sd/Makefile.objs
+++ b/hw/sd/Makefile.objs
@@ -10,3 +10,4 @@ common-obj-$(CONFIG_OMAP) += omap_mmc.o
 common-obj-$(CONFIG_PXA2XX) += pxa2xx_mmci.o
 common-obj-$(CONFIG_RASPI) += bcm2835_sdhost.o
 common-obj-$(CONFIG_ASPEED_SOC) += aspeed_sdhci.o
+common-obj-$(CONFIG_CADENCE_SDHCI) += cadence_sdhci.o
diff --git a/hw/sd/cadence_sdhci.c b/hw/sd/cadence_sdhci.c
new file mode 100644
index 0000000..67ffd14
--- /dev/null
+++ b/hw/sd/cadence_sdhci.c
@@ -0,0 +1,162 @@
+/*
+ * Cadence SDHCI 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/error-report.h"
+#include "qemu/log.h"
+#include "qapi/error.h"
+#include "migration/vmstate.h"
+#include "hw/irq.h"
+#include "hw/sd/cadence_sdhci.h"
+#include "sdhci-internal.h"
+
+#define TO_REG(addr)    ((addr) / sizeof(uint32_t))
+
+static void cadence_sdhci_reset(DeviceState *dev)
+{
+    CadenceSDHCIState *sdhci = CADENCE_SDHCI(dev);
+
+    memset(sdhci->regs, 0, CADENCE_SDHCI_REG_SIZE);
+    sdhci->regs[TO_REG(SDHCI_CDNS_HRS00)] = SDHCI_CDNS_HRS00_POR_VAL;
+}
+
+static uint64_t cadence_sdhci_read(void *opaque, hwaddr addr, unsigned int size)
+{
+    uint32_t val = 0;
+    CadenceSDHCIState *sdhci = opaque;
+
+    if (addr < CADENCE_SDHCI_REG_SIZE) {
+        val = sdhci->regs[TO_REG(addr)];
+    } else {
+        qemu_log_mask(LOG_GUEST_ERROR,
+                      "%s: Out-of-bounds read at 0x%" HWADDR_PRIx "\n",
+                      __func__, addr);
+    }
+
+    return (uint64_t)val;
+}
+
+static void cadence_sdhci_write(void *opaque, hwaddr addr, uint64_t val,
+                                unsigned int size)
+{
+    CadenceSDHCIState *sdhci = opaque;
+    uint32_t val32 = (uint32_t)val;
+
+    switch (addr) {
+    case SDHCI_CDNS_HRS00:
+        /*
+         * The only writable bit is SWR (software reset) and it automatically
+         * clears to zero, so essentially this register remains unchanged.
+         */
+        if (val32 & SDHCI_CDNS_HRS00_SWR) {
+            cadence_sdhci_reset(DEVICE(sdhci));
+            sdhci_poweron_reset(DEVICE(&sdhci->slot));
+        }
+
+        break;
+    case SDHCI_CDNS_HRS04:
+        /*
+         * Only emulate the ACK bit behavior when read or write transaction
+         * are requested.
+         */
+        if (val32 & (SDHCI_CDNS_HRS04_WR | SDHCI_CDNS_HRS04_RD)) {
+            val32 |= SDHCI_CDNS_HRS04_ACK;
+        } else {
+            val32 &= ~SDHCI_CDNS_HRS04_ACK;
+        }
+
+        sdhci->regs[TO_REG(addr)] = val32;
+        break;
+    case SDHCI_CDNS_HRS06:
+        if (val32 & SDHCI_CDNS_HRS06_TUNE_UP) {
+            val32 &= ~SDHCI_CDNS_HRS06_TUNE_UP;
+        }
+
+        sdhci->regs[TO_REG(addr)] = val32;
+        break;
+    default:
+        if (addr < CADENCE_SDHCI_REG_SIZE) {
+            sdhci->regs[TO_REG(addr)] = val32;
+        } else {
+            qemu_log_mask(LOG_GUEST_ERROR,
+                          "%s: Out-of-bounds write at 0x%" HWADDR_PRIx "\n",
+                          __func__, addr);
+        }
+    }
+}
+
+static const MemoryRegionOps cadence_sdhci_ops = {
+    .read = cadence_sdhci_read,
+    .write = cadence_sdhci_write,
+    .endianness = DEVICE_NATIVE_ENDIAN,
+    .valid = {
+        .min_access_size = 4,
+        .max_access_size = 4,
+    }
+};
+
+static void cadence_sdhci_realize(DeviceState *dev, Error **errp)
+{
+    SysBusDevice *sbd = SYS_BUS_DEVICE(dev);
+    CadenceSDHCIState *sdhci = CADENCE_SDHCI(dev);
+    SysBusDevice *sbd_slot = SYS_BUS_DEVICE(&sdhci->slot);
+
+    memory_region_init_io(&sdhci->iomem, OBJECT(sdhci), &cadence_sdhci_ops,
+                          sdhci, TYPE_CADENCE_SDHCI, 0x1000);
+    sysbus_init_mmio(sbd, &sdhci->iomem);
+
+    sysbus_realize(sbd_slot, errp);
+    memory_region_add_subregion(&sdhci->iomem, SDHCI_CDNS_SRS_BASE,
+                                &sdhci->slot.iomem);
+}
+
+static const VMStateDescription vmstate_cadence_sdhci = {
+    .name = TYPE_CADENCE_SDHCI,
+    .version_id = 1,
+    .fields = (VMStateField[]) {
+        VMSTATE_UINT32_ARRAY(regs, CadenceSDHCIState, CADENCE_SDHCI_NUM_REGS),
+        VMSTATE_END_OF_LIST(),
+    },
+};
+
+static void cadence_sdhci_class_init(ObjectClass *classp, void *data)
+{
+    DeviceClass *dc = DEVICE_CLASS(classp);
+
+    dc->realize = cadence_sdhci_realize;
+    dc->reset = cadence_sdhci_reset;
+    dc->vmsd = &vmstate_cadence_sdhci;
+}
+
+static TypeInfo cadence_sdhci_info = {
+    .name          = TYPE_CADENCE_SDHCI,
+    .parent        = TYPE_SYS_BUS_DEVICE,
+    .instance_size = sizeof(CadenceSDHCIState),
+    .class_init    = cadence_sdhci_class_init,
+};
+
+static void cadence_sdhci_register_types(void)
+{
+    type_register_static(&cadence_sdhci_info);
+}
+
+type_init(cadence_sdhci_register_types)
diff --git a/include/hw/sd/cadence_sdhci.h b/include/hw/sd/cadence_sdhci.h
new file mode 100644
index 0000000..9ff78a9
--- /dev/null
+++ b/include/hw/sd/cadence_sdhci.h
@@ -0,0 +1,65 @@
+/*
+ * Cadence SDHCI 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/>.
+ */
+
+#ifndef CADENCE_SDHCI_H
+#define CADENCE_SDHCI_H
+
+#include "qemu/bitops.h"
+#include "hw/sd/sdhci.h"
+
+/* HRS - Host Register Set (specific to Cadence) */
+
+#define SDHCI_CDNS_HRS00                0x00    /* general information */
+#define SDHCI_CDNS_HRS00_SWR                BIT(0)
+#define SDHCI_CDNS_HRS00_POR_VAL            0x00010000
+
+#define SDHCI_CDNS_HRS04                0x10    /* PHY access port */
+#define SDHCI_CDNS_HRS04_WR                 BIT(24)
+#define SDHCI_CDNS_HRS04_RD                 BIT(25)
+#define SDHCI_CDNS_HRS04_ACK                BIT(26)
+
+#define SDHCI_CDNS_HRS06                0x18    /* eMMC control */
+#define SDHCI_CDNS_HRS06_TUNE_UP            BIT(15)
+
+/* SRS - Slot Register Set (SDHCI-compatible) */
+#define SDHCI_CDNS_SRS_BASE             0x200
+
+#define CADENCE_SDHCI_CAPABILITIES 0x01E80080
+#define CADENCE_SDHCI_REG_SIZE     0x100
+#define CADENCE_SDHCI_NUM_REGS     (CADENCE_SDHCI_REG_SIZE / sizeof(uint32_t))
+
+typedef struct CadenceSDHCIState {
+    SysBusDevice parent;
+
+    MemoryRegion iomem;
+    qemu_irq irq;
+
+    uint32_t regs[CADENCE_SDHCI_NUM_REGS];
+
+    SDHCIState slot;
+} CadenceSDHCIState;
+
+#define TYPE_CADENCE_SDHCI  "cadence.sdhci"
+#define CADENCE_SDHCI(obj)  OBJECT_CHECK(CadenceSDHCIState, (obj), \
+                                         TYPE_CADENCE_SDHCI)
+
+#endif /* CADENCE_SDHCI_H */
-- 
2.7.4