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-rw-r--r--hw/milkymist-hpdmc.c161
1 files changed, 161 insertions, 0 deletions
diff --git a/hw/milkymist-hpdmc.c b/hw/milkymist-hpdmc.c
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+/*
+ * QEMU model of the Milkymist High Performance Dynamic Memory Controller.
+ *
+ * Copyright (c) 2010 Michael Walle <michael@walle.cc>
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library 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
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, see <http://www.gnu.org/licenses/>.
+ *
+ *
+ * Specification available at:
+ * http://www.milkymist.org/socdoc/hpdmc.pdf
+ */
+
+#include "hw.h"
+#include "sysbus.h"
+#include "trace.h"
+#include "qemu-error.h"
+
+enum {
+ R_SYSTEM = 0,
+ R_BYPASS,
+ R_TIMING,
+ R_IODELAY,
+ R_MAX
+};
+
+enum {
+ IODELAY_DQSDELAY_RDY = (1<<5),
+ IODELAY_PLL1_LOCKED = (1<<6),
+ IODELAY_PLL2_LOCKED = (1<<7),
+};
+
+struct MilkymistHpdmcState {
+ SysBusDevice busdev;
+
+ uint32_t regs[R_MAX];
+};
+typedef struct MilkymistHpdmcState MilkymistHpdmcState;
+
+static uint32_t hpdmc_read(void *opaque, target_phys_addr_t addr)
+{
+ MilkymistHpdmcState *s = opaque;
+ uint32_t r = 0;
+
+ addr >>= 2;
+ switch (addr) {
+ case R_SYSTEM:
+ case R_BYPASS:
+ case R_TIMING:
+ case R_IODELAY:
+ r = s->regs[addr];
+ break;
+
+ default:
+ error_report("milkymist_hpdmc: read access to unknown register 0x"
+ TARGET_FMT_plx, addr << 2);
+ break;
+ }
+
+ trace_milkymist_hpdmc_memory_read(addr << 2, r);
+
+ return r;
+}
+
+static void hpdmc_write(void *opaque, target_phys_addr_t addr, uint32_t value)
+{
+ MilkymistHpdmcState *s = opaque;
+
+ trace_milkymist_hpdmc_memory_write(addr, value);
+
+ addr >>= 2;
+ switch (addr) {
+ case R_SYSTEM:
+ case R_BYPASS:
+ case R_TIMING:
+ s->regs[addr] = value;
+ break;
+ case R_IODELAY:
+ /* ignore writes */
+ break;
+
+ default:
+ error_report("milkymist_hpdmc: write access to unknown register 0x"
+ TARGET_FMT_plx, addr << 2);
+ break;
+ }
+}
+
+static CPUReadMemoryFunc * const hpdmc_read_fn[] = {
+ NULL,
+ NULL,
+ &hpdmc_read,
+};
+
+static CPUWriteMemoryFunc * const hpdmc_write_fn[] = {
+ NULL,
+ NULL,
+ &hpdmc_write,
+};
+
+static void milkymist_hpdmc_reset(DeviceState *d)
+{
+ MilkymistHpdmcState *s = container_of(d, MilkymistHpdmcState, busdev.qdev);
+ int i;
+
+ for (i = 0; i < R_MAX; i++) {
+ s->regs[i] = 0;
+ }
+
+ /* defaults */
+ s->regs[R_IODELAY] = IODELAY_DQSDELAY_RDY | IODELAY_PLL1_LOCKED
+ | IODELAY_PLL2_LOCKED;
+}
+
+static int milkymist_hpdmc_init(SysBusDevice *dev)
+{
+ MilkymistHpdmcState *s = FROM_SYSBUS(typeof(*s), dev);
+ int hpdmc_regs;
+
+ hpdmc_regs = cpu_register_io_memory(hpdmc_read_fn, hpdmc_write_fn, s,
+ DEVICE_NATIVE_ENDIAN);
+ sysbus_init_mmio(dev, R_MAX * 4, hpdmc_regs);
+
+ return 0;
+}
+
+static const VMStateDescription vmstate_milkymist_hpdmc = {
+ .name = "milkymist-hpdmc",
+ .version_id = 1,
+ .minimum_version_id = 1,
+ .minimum_version_id_old = 1,
+ .fields = (VMStateField[]) {
+ VMSTATE_UINT32_ARRAY(regs, MilkymistHpdmcState, R_MAX),
+ VMSTATE_END_OF_LIST()
+ }
+};
+
+static SysBusDeviceInfo milkymist_hpdmc_info = {
+ .init = milkymist_hpdmc_init,
+ .qdev.name = "milkymist-hpdmc",
+ .qdev.size = sizeof(MilkymistHpdmcState),
+ .qdev.vmsd = &vmstate_milkymist_hpdmc,
+ .qdev.reset = milkymist_hpdmc_reset,
+};
+
+static void milkymist_hpdmc_register(void)
+{
+ sysbus_register_withprop(&milkymist_hpdmc_info);
+}
+
+device_init(milkymist_hpdmc_register)