hw/misc: Add a basic Aspeed LPC controller model

This is a very minimal framework to access registers which are used to
configure the AHB memory mapping of the flash chips on the LPC HC
Firmware address space.

Signed-off-by: Cédric Le Goater <clg@kaod.org>
Signed-off-by: Andrew Jeffery <andrew@aj.id.au>
Message-Id: <20210302014317.915120-5-andrew@aj.id.au>
Signed-off-by: Cédric Le Goater <clg@kaod.org>

2 files changed, 137 insertions, 1 deletions

diff --git a/hw/misc/aspeed_lpc.c b/hw/misc/aspeed_lpc.c
new file mode 100644
index 0000000000..e668e985ff
--- /dev/null
+++ b/hw/misc/aspeed_lpc.c
@@ -0,0 +1,131 @@
+/*
+ *  ASPEED LPC Controller
+ *
+ *  Copyright (C) 2017-2018 IBM Corp.
+ *
+ * This code is licensed under the GPL version 2 or later.  See
+ * the COPYING file in the top-level directory.
+ */
+
+#include "qemu/osdep.h"
+#include "qemu/log.h"
+#include "qemu/error-report.h"
+#include "hw/misc/aspeed_lpc.h"
+#include "qapi/error.h"
+#include "hw/qdev-properties.h"
+#include "migration/vmstate.h"
+
+#define TO_REG(offset) ((offset) >> 2)
+
+#define HICR0                TO_REG(0x00)
+#define HICR1                TO_REG(0x04)
+#define HICR2                TO_REG(0x08)
+#define HICR3                TO_REG(0x0C)
+#define HICR4                TO_REG(0x10)
+#define HICR5                TO_REG(0x80)
+#define HICR6                TO_REG(0x84)
+#define HICR7                TO_REG(0x88)
+#define HICR8                TO_REG(0x8C)
+
+static uint64_t aspeed_lpc_read(void *opaque, hwaddr offset, unsigned size)
+{
+    AspeedLPCState *s = ASPEED_LPC(opaque);
+    int reg = TO_REG(offset);
+
+    if (reg >= ARRAY_SIZE(s->regs)) {
+        qemu_log_mask(LOG_GUEST_ERROR,
+                      "%s: Out-of-bounds read at offset 0x%" HWADDR_PRIx "\n",
+                      __func__, offset);
+        return 0;
+    }
+
+    return s->regs[reg];
+}
+
+static void aspeed_lpc_write(void *opaque, hwaddr offset, uint64_t data,
+                             unsigned int size)
+{
+    AspeedLPCState *s = ASPEED_LPC(opaque);
+    int reg = TO_REG(offset);
+
+    if (reg >= ARRAY_SIZE(s->regs)) {
+        qemu_log_mask(LOG_GUEST_ERROR,
+                      "%s: Out-of-bounds write at offset 0x%" HWADDR_PRIx "\n",
+                      __func__, offset);
+        return;
+    }
+
+    s->regs[reg] = data;
+}
+
+static const MemoryRegionOps aspeed_lpc_ops = {
+    .read = aspeed_lpc_read,
+    .write = aspeed_lpc_write,
+    .endianness = DEVICE_LITTLE_ENDIAN,
+    .valid = {
+        .min_access_size = 1,
+        .max_access_size = 4,
+    },
+};
+
+static void aspeed_lpc_reset(DeviceState *dev)
+{
+    struct AspeedLPCState *s = ASPEED_LPC(dev);
+
+    memset(s->regs, 0, sizeof(s->regs));
+
+    s->regs[HICR7] = s->hicr7;
+}
+
+static void aspeed_lpc_realize(DeviceState *dev, Error **errp)
+{
+    AspeedLPCState *s = ASPEED_LPC(dev);
+    SysBusDevice *sbd = SYS_BUS_DEVICE(dev);
+
+    sysbus_init_irq(sbd, &s->irq);
+
+    memory_region_init_io(&s->iomem, OBJECT(s), &aspeed_lpc_ops, s,
+            TYPE_ASPEED_LPC, 0x1000);
+
+    sysbus_init_mmio(sbd, &s->iomem);
+}
+
+static const VMStateDescription vmstate_aspeed_lpc = {
+    .name = TYPE_ASPEED_LPC,
+    .version_id = 1,
+    .minimum_version_id = 1,
+    .fields = (VMStateField[]) {
+        VMSTATE_UINT32_ARRAY(regs, AspeedLPCState, ASPEED_LPC_NR_REGS),
+        VMSTATE_END_OF_LIST(),
+    }
+};
+
+static Property aspeed_lpc_properties[] = {
+    DEFINE_PROP_UINT32("hicr7", AspeedLPCState, hicr7, 0),
+    DEFINE_PROP_END_OF_LIST(),
+};
+
+static void aspeed_lpc_class_init(ObjectClass *klass, void *data)
+{
+    DeviceClass *dc = DEVICE_CLASS(klass);
+
+    dc->realize = aspeed_lpc_realize;
+    dc->reset = aspeed_lpc_reset;
+    dc->desc = "Aspeed LPC Controller",
+    dc->vmsd = &vmstate_aspeed_lpc;
+    device_class_set_props(dc, aspeed_lpc_properties);
+}
+
+static const TypeInfo aspeed_lpc_info = {
+    .name = TYPE_ASPEED_LPC,
+    .parent = TYPE_SYS_BUS_DEVICE,
+    .instance_size = sizeof(AspeedLPCState),
+    .class_init = aspeed_lpc_class_init,
+};
+
+static void aspeed_lpc_register_types(void)
+{
+    type_register_static(&aspeed_lpc_info);
+}
+
+type_init(aspeed_lpc_register_types);
diff --git a/hw/misc/meson.build b/hw/misc/meson.build
index 629283957f..e3263383cd 100644
--- a/hw/misc/meson.build
+++ b/hw/misc/meson.build
@@ -102,7 +102,12 @@ softmmu_ss.add(when: 'CONFIG_ARMSSE_MHU', if_true: files('armsse-mhu.c'))
 softmmu_ss.add(when: 'CONFIG_PVPANIC_ISA', if_true: files('pvpanic-isa.c'))
 softmmu_ss.add(when: 'CONFIG_PVPANIC_PCI', if_true: files('pvpanic-pci.c'))
 softmmu_ss.add(when: 'CONFIG_AUX', if_true: files('auxbus.c'))
-softmmu_ss.add(when: 'CONFIG_ASPEED_SOC', if_true: files('aspeed_scu.c', 'aspeed_sdmc.c', 'aspeed_xdma.c'))
+softmmu_ss.add(when: 'CONFIG_ASPEED_SOC', if_true: files(
+  'aspeed_lpc.c',
+  'aspeed_scu.c',
+  'aspeed_sdmc.c',
+  'aspeed_xdma.c'))
+
 softmmu_ss.add(when: 'CONFIG_MSF2', if_true: files('msf2-sysreg.c'))
 softmmu_ss.add(when: 'CONFIG_NRF51_SOC', if_true: files('nrf51_rng.c'))