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-rw-r--r--hw/milkymist-sysctl.c318
1 files changed, 318 insertions, 0 deletions
diff --git a/hw/milkymist-sysctl.c b/hw/milkymist-sysctl.c
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+++ b/hw/milkymist-sysctl.c
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+/*
+ * QEMU model of the Milkymist System 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/sysctl.pdf
+ */
+
+#include "hw.h"
+#include "sysbus.h"
+#include "sysemu.h"
+#include "trace.h"
+#include "qemu-timer.h"
+#include "qemu-error.h"
+
+enum {
+ CTRL_ENABLE = (1<<0),
+ CTRL_AUTORESTART = (1<<1),
+};
+
+enum {
+ ICAP_READY = (1<<0),
+};
+
+enum {
+ R_GPIO_IN = 0,
+ R_GPIO_OUT,
+ R_GPIO_INTEN,
+ R_RESERVED0,
+ R_TIMER0_CONTROL,
+ R_TIMER0_COMPARE,
+ R_TIMER0_COUNTER,
+ R_RESERVED1,
+ R_TIMER1_CONTROL,
+ R_TIMER1_COMPARE,
+ R_TIMER1_COUNTER,
+ R_RESERVED2,
+ R_RESERVED3,
+ R_ICAP,
+ R_CAPABILITIES,
+ R_SYSTEM_ID,
+ R_MAX
+};
+
+struct MilkymistSysctlState {
+ SysBusDevice busdev;
+
+ QEMUBH *bh0;
+ QEMUBH *bh1;
+ ptimer_state *ptimer0;
+ ptimer_state *ptimer1;
+
+ uint32_t freq_hz;
+ uint32_t capabilities;
+ uint32_t systemid;
+ uint32_t strappings;
+
+ uint32_t regs[R_MAX];
+
+ qemu_irq gpio_irq;
+ qemu_irq timer0_irq;
+ qemu_irq timer1_irq;
+};
+typedef struct MilkymistSysctlState MilkymistSysctlState;
+
+static void sysctl_icap_write(MilkymistSysctlState *s, uint32_t value)
+{
+ trace_milkymist_sysctl_icap_write(value);
+ switch (value & 0xffff) {
+ case 0x000e:
+ qemu_system_shutdown_request();
+ break;
+ }
+}
+
+static uint32_t sysctl_read(void *opaque, target_phys_addr_t addr)
+{
+ MilkymistSysctlState *s = opaque;
+ uint32_t r = 0;
+
+ addr >>= 2;
+ switch (addr) {
+ case R_TIMER0_COUNTER:
+ r = (uint32_t)ptimer_get_count(s->ptimer0);
+ /* milkymist timer counts up */
+ r = s->regs[R_TIMER0_COMPARE] - r;
+ break;
+ case R_TIMER1_COUNTER:
+ r = (uint32_t)ptimer_get_count(s->ptimer1);
+ /* milkymist timer counts up */
+ r = s->regs[R_TIMER1_COMPARE] - r;
+ break;
+ case R_GPIO_IN:
+ case R_GPIO_OUT:
+ case R_GPIO_INTEN:
+ case R_TIMER0_CONTROL:
+ case R_TIMER0_COMPARE:
+ case R_TIMER1_CONTROL:
+ case R_TIMER1_COMPARE:
+ case R_ICAP:
+ case R_CAPABILITIES:
+ case R_SYSTEM_ID:
+ r = s->regs[addr];
+ break;
+
+ default:
+ error_report("milkymist_sysctl: read access to unkown register 0x"
+ TARGET_FMT_plx, addr << 2);
+ break;
+ }
+
+ trace_milkymist_sysctl_memory_read(addr << 2, r);
+
+ return r;
+}
+
+static void sysctl_write(void *opaque, target_phys_addr_t addr, uint32_t value)
+{
+ MilkymistSysctlState *s = opaque;
+
+ trace_milkymist_sysctl_memory_write(addr, value);
+
+ addr >>= 2;
+ switch (addr) {
+ case R_GPIO_OUT:
+ case R_GPIO_INTEN:
+ case R_TIMER0_COUNTER:
+ case R_TIMER1_COUNTER:
+ s->regs[addr] = value;
+ break;
+ case R_TIMER0_COMPARE:
+ ptimer_set_limit(s->ptimer0, value, 0);
+ s->regs[addr] = value;
+ break;
+ case R_TIMER1_COMPARE:
+ ptimer_set_limit(s->ptimer1, value, 0);
+ s->regs[addr] = value;
+ break;
+ case R_TIMER0_CONTROL:
+ s->regs[addr] = value;
+ if (s->regs[R_TIMER0_CONTROL] & CTRL_ENABLE) {
+ trace_milkymist_sysctl_start_timer0();
+ ptimer_set_count(s->ptimer0,
+ s->regs[R_TIMER0_COMPARE] - s->regs[R_TIMER0_COUNTER]);
+ ptimer_run(s->ptimer0, 0);
+ } else {
+ trace_milkymist_sysctl_stop_timer0();
+ ptimer_stop(s->ptimer0);
+ }
+ break;
+ case R_TIMER1_CONTROL:
+ s->regs[addr] = value;
+ if (s->regs[R_TIMER1_CONTROL] & CTRL_ENABLE) {
+ trace_milkymist_sysctl_start_timer1();
+ ptimer_set_count(s->ptimer1,
+ s->regs[R_TIMER1_COMPARE] - s->regs[R_TIMER1_COUNTER]);
+ ptimer_run(s->ptimer1, 0);
+ } else {
+ trace_milkymist_sysctl_stop_timer1();
+ ptimer_stop(s->ptimer1);
+ }
+ break;
+ case R_ICAP:
+ sysctl_icap_write(s, value);
+ break;
+ case R_SYSTEM_ID:
+ qemu_system_reset_request();
+ break;
+
+ case R_GPIO_IN:
+ case R_CAPABILITIES:
+ error_report("milkymist_sysctl: write to read-only register 0x"
+ TARGET_FMT_plx, addr << 2);
+ break;
+
+ default:
+ error_report("milkymist_sysctl: write access to unkown register 0x"
+ TARGET_FMT_plx, addr << 2);
+ break;
+ }
+}
+
+static CPUReadMemoryFunc * const sysctl_read_fn[] = {
+ NULL,
+ NULL,
+ &sysctl_read,
+};
+
+static CPUWriteMemoryFunc * const sysctl_write_fn[] = {
+ NULL,
+ NULL,
+ &sysctl_write,
+};
+
+static void timer0_hit(void *opaque)
+{
+ MilkymistSysctlState *s = opaque;
+
+ if (!(s->regs[R_TIMER0_CONTROL] & CTRL_AUTORESTART)) {
+ s->regs[R_TIMER0_CONTROL] &= ~CTRL_ENABLE;
+ trace_milkymist_sysctl_stop_timer0();
+ ptimer_stop(s->ptimer0);
+ }
+
+ trace_milkymist_sysctl_pulse_irq_timer0();
+ qemu_irq_pulse(s->timer0_irq);
+}
+
+static void timer1_hit(void *opaque)
+{
+ MilkymistSysctlState *s = opaque;
+
+ if (!(s->regs[R_TIMER1_CONTROL] & CTRL_AUTORESTART)) {
+ s->regs[R_TIMER1_CONTROL] &= ~CTRL_ENABLE;
+ trace_milkymist_sysctl_stop_timer1();
+ ptimer_stop(s->ptimer1);
+ }
+
+ trace_milkymist_sysctl_pulse_irq_timer1();
+ qemu_irq_pulse(s->timer1_irq);
+}
+
+static void milkymist_sysctl_reset(DeviceState *d)
+{
+ MilkymistSysctlState *s =
+ container_of(d, MilkymistSysctlState, busdev.qdev);
+ int i;
+
+ for (i = 0; i < R_MAX; i++) {
+ s->regs[i] = 0;
+ }
+
+ ptimer_stop(s->ptimer0);
+ ptimer_stop(s->ptimer1);
+
+ /* defaults */
+ s->regs[R_ICAP] = ICAP_READY;
+ s->regs[R_SYSTEM_ID] = s->systemid;
+ s->regs[R_CAPABILITIES] = s->capabilities;
+ s->regs[R_GPIO_IN] = s->strappings;
+}
+
+static int milkymist_sysctl_init(SysBusDevice *dev)
+{
+ MilkymistSysctlState *s = FROM_SYSBUS(typeof(*s), dev);
+ int sysctl_regs;
+
+ sysbus_init_irq(dev, &s->gpio_irq);
+ sysbus_init_irq(dev, &s->timer0_irq);
+ sysbus_init_irq(dev, &s->timer1_irq);
+
+ s->bh0 = qemu_bh_new(timer0_hit, s);
+ s->bh1 = qemu_bh_new(timer1_hit, s);
+ s->ptimer0 = ptimer_init(s->bh0);
+ s->ptimer1 = ptimer_init(s->bh1);
+ ptimer_set_freq(s->ptimer0, s->freq_hz);
+ ptimer_set_freq(s->ptimer1, s->freq_hz);
+
+ sysctl_regs = cpu_register_io_memory(sysctl_read_fn, sysctl_write_fn, s,
+ DEVICE_NATIVE_ENDIAN);
+ sysbus_init_mmio(dev, R_MAX * 4, sysctl_regs);
+
+ return 0;
+}
+
+static const VMStateDescription vmstate_milkymist_sysctl = {
+ .name = "milkymist-sysctl",
+ .version_id = 1,
+ .minimum_version_id = 1,
+ .minimum_version_id_old = 1,
+ .fields = (VMStateField[]) {
+ VMSTATE_UINT32_ARRAY(regs, MilkymistSysctlState, R_MAX),
+ VMSTATE_PTIMER(ptimer0, MilkymistSysctlState),
+ VMSTATE_PTIMER(ptimer1, MilkymistSysctlState),
+ VMSTATE_END_OF_LIST()
+ }
+};
+
+static SysBusDeviceInfo milkymist_sysctl_info = {
+ .init = milkymist_sysctl_init,
+ .qdev.name = "milkymist-sysctl",
+ .qdev.size = sizeof(MilkymistSysctlState),
+ .qdev.vmsd = &vmstate_milkymist_sysctl,
+ .qdev.reset = milkymist_sysctl_reset,
+ .qdev.props = (Property[]) {
+ DEFINE_PROP_UINT32("frequency", MilkymistSysctlState,
+ freq_hz, 80000000),
+ DEFINE_PROP_UINT32("capabilities", MilkymistSysctlState,
+ capabilities, 0x00000000),
+ DEFINE_PROP_UINT32("systemid", MilkymistSysctlState,
+ systemid, 0x10014d31),
+ DEFINE_PROP_UINT32("gpio_strappings", MilkymistSysctlState,
+ strappings, 0x00000001),
+ DEFINE_PROP_END_OF_LIST(),
+ }
+};
+
+static void milkymist_sysctl_register(void)
+{
+ sysbus_register_withprop(&milkymist_sysctl_info);
+}
+
+device_init(milkymist_sysctl_register)