diff options
Diffstat (limited to 'src/hw/timer/a9gtimer.c')
| -rw-r--r-- | src/hw/timer/a9gtimer.c | 369 |
1 files changed, 369 insertions, 0 deletions
diff --git a/src/hw/timer/a9gtimer.c b/src/hw/timer/a9gtimer.c new file mode 100644 index 0000000..dd4aae8 --- /dev/null +++ b/src/hw/timer/a9gtimer.c @@ -0,0 +1,369 @@ +/* + * Global peripheral timer block for ARM A9MP + * + * (C) 2013 Xilinx Inc. + * + * Written by François LEGAL + * Written by Peter Crosthwaite <peter.crosthwaite@xilinx.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 "hw/timer/a9gtimer.h" +#include "qemu/timer.h" +#include "qemu/bitops.h" +#include "qemu/log.h" + +#ifndef A9_GTIMER_ERR_DEBUG +#define A9_GTIMER_ERR_DEBUG 0 +#endif + +#define DB_PRINT_L(level, ...) do { \ + if (A9_GTIMER_ERR_DEBUG > (level)) { \ + fprintf(stderr, ": %s: ", __func__); \ + fprintf(stderr, ## __VA_ARGS__); \ + } \ +} while (0); + +#define DB_PRINT(...) DB_PRINT_L(0, ## __VA_ARGS__) + +static inline int a9_gtimer_get_current_cpu(A9GTimerState *s) +{ + if (current_cpu->cpu_index >= s->num_cpu) { + hw_error("a9gtimer: num-cpu %d but this cpu is %d!\n", + s->num_cpu, current_cpu->cpu_index); + } + return current_cpu->cpu_index; +} + +static inline uint64_t a9_gtimer_get_conv(A9GTimerState *s) +{ + uint64_t prescale = extract32(s->control, R_CONTROL_PRESCALER_SHIFT, + R_CONTROL_PRESCALER_LEN); + + return (prescale + 1) * 10; +} + +static A9GTimerUpdate a9_gtimer_get_update(A9GTimerState *s) +{ + A9GTimerUpdate ret; + + ret.now = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL); + ret.new = s->ref_counter + + (ret.now - s->cpu_ref_time) / a9_gtimer_get_conv(s); + return ret; +} + +static void a9_gtimer_update(A9GTimerState *s, bool sync) +{ + + A9GTimerUpdate update = a9_gtimer_get_update(s); + int i; + int64_t next_cdiff = 0; + + for (i = 0; i < s->num_cpu; ++i) { + A9GTimerPerCPU *gtb = &s->per_cpu[i]; + int64_t cdiff = 0; + + if ((s->control & R_CONTROL_TIMER_ENABLE) && + (gtb->control & R_CONTROL_COMP_ENABLE)) { + /* R2p0+, where the compare function is >= */ + while (gtb->compare < update.new) { + DB_PRINT("Compare event happened for CPU %d\n", i); + gtb->status = 1; + if (gtb->control & R_CONTROL_AUTO_INCREMENT) { + DB_PRINT("Auto incrementing timer compare by %" PRId32 "\n", + gtb->inc); + gtb->compare += gtb->inc; + } else { + break; + } + } + cdiff = (int64_t)gtb->compare - (int64_t)update.new + 1; + if (cdiff > 0 && (cdiff < next_cdiff || !next_cdiff)) { + next_cdiff = cdiff; + } + } + + qemu_set_irq(gtb->irq, + gtb->status && (gtb->control & R_CONTROL_IRQ_ENABLE)); + } + + timer_del(s->timer); + if (next_cdiff) { + DB_PRINT("scheduling qemu_timer to fire again in %" + PRIx64 " cycles\n", next_cdiff); + timer_mod(s->timer, update.now + next_cdiff * a9_gtimer_get_conv(s)); + } + + if (s->control & R_CONTROL_TIMER_ENABLE) { + s->counter = update.new; + } + + if (sync) { + s->cpu_ref_time = update.now; + s->ref_counter = s->counter; + } +} + +static void a9_gtimer_update_no_sync(void *opaque) +{ + A9GTimerState *s = A9_GTIMER(opaque); + + a9_gtimer_update(s, false); +} + +static uint64_t a9_gtimer_read(void *opaque, hwaddr addr, unsigned size) +{ + A9GTimerPerCPU *gtb = (A9GTimerPerCPU *)opaque; + A9GTimerState *s = gtb->parent; + A9GTimerUpdate update; + uint64_t ret = 0; + int shift = 0; + + switch (addr) { + case R_COUNTER_HI: + shift = 32; + /* fallthrough */ + case R_COUNTER_LO: + update = a9_gtimer_get_update(s); + ret = extract64(update.new, shift, 32); + break; + case R_CONTROL: + ret = s->control | gtb->control; + break; + case R_INTERRUPT_STATUS: + ret = gtb->status; + break; + case R_COMPARATOR_HI: + shift = 32; + /* fallthrough */ + case R_COMPARATOR_LO: + ret = extract64(gtb->compare, shift, 32); + break; + case R_AUTO_INCREMENT: + ret = gtb->inc; + break; + default: + qemu_log_mask(LOG_GUEST_ERROR, "bad a9gtimer register: %x\n", + (unsigned)addr); + return 0; + } + + DB_PRINT("addr:%#x data:%#08" PRIx64 "\n", (unsigned)addr, ret); + return ret; +} + +static void a9_gtimer_write(void *opaque, hwaddr addr, uint64_t value, + unsigned size) +{ + A9GTimerPerCPU *gtb = (A9GTimerPerCPU *)opaque; + A9GTimerState *s = gtb->parent; + int shift = 0; + + DB_PRINT("addr:%#x data:%#08" PRIx64 "\n", (unsigned)addr, value); + + switch (addr) { + case R_COUNTER_HI: + shift = 32; + /* fallthrough */ + case R_COUNTER_LO: + /* + * Keep it simple - ARM docco explicitly says to disable timer before + * modding it, so dont bother trying to do all the difficult on the fly + * timer modifications - (if they even work in real hardware??). + */ + if (s->control & R_CONTROL_TIMER_ENABLE) { + qemu_log_mask(LOG_GUEST_ERROR, "Cannot mod running ARM gtimer\n"); + return; + } + s->counter = deposit64(s->counter, shift, 32, value); + return; + case R_CONTROL: + a9_gtimer_update(s, (value ^ s->control) & R_CONTROL_NEEDS_SYNC); + gtb->control = value & R_CONTROL_BANKED; + s->control = value & ~R_CONTROL_BANKED; + break; + case R_INTERRUPT_STATUS: + a9_gtimer_update(s, false); + gtb->status &= ~value; + break; + case R_COMPARATOR_HI: + shift = 32; + /* fallthrough */ + case R_COMPARATOR_LO: + a9_gtimer_update(s, false); + gtb->compare = deposit64(gtb->compare, shift, 32, value); + break; + case R_AUTO_INCREMENT: + gtb->inc = value; + return; + default: + return; + } + + a9_gtimer_update(s, false); +} + +/* Wrapper functions to implement the "read global timer for + * the current CPU" memory regions. + */ +static uint64_t a9_gtimer_this_read(void *opaque, hwaddr addr, + unsigned size) +{ + A9GTimerState *s = A9_GTIMER(opaque); + int id = a9_gtimer_get_current_cpu(s); + + /* no \n so concatenates with message from read fn */ + DB_PRINT("CPU:%d:", id); + + return a9_gtimer_read(&s->per_cpu[id], addr, size); +} + +static void a9_gtimer_this_write(void *opaque, hwaddr addr, + uint64_t value, unsigned size) +{ + A9GTimerState *s = A9_GTIMER(opaque); + int id = a9_gtimer_get_current_cpu(s); + + /* no \n so concatenates with message from write fn */ + DB_PRINT("CPU:%d:", id); + + a9_gtimer_write(&s->per_cpu[id], addr, value, size); +} + +static const MemoryRegionOps a9_gtimer_this_ops = { + .read = a9_gtimer_this_read, + .write = a9_gtimer_this_write, + .valid = { + .min_access_size = 4, + .max_access_size = 4, + }, + .endianness = DEVICE_NATIVE_ENDIAN, +}; + +static const MemoryRegionOps a9_gtimer_ops = { + .read = a9_gtimer_read, + .write = a9_gtimer_write, + .valid = { + .min_access_size = 4, + .max_access_size = 4, + }, + .endianness = DEVICE_NATIVE_ENDIAN, +}; + +static void a9_gtimer_reset(DeviceState *dev) +{ + A9GTimerState *s = A9_GTIMER(dev); + int i; + + s->counter = 0; + s->control = 0; + + for (i = 0; i < s->num_cpu; i++) { + A9GTimerPerCPU *gtb = &s->per_cpu[i]; + + gtb->control = 0; + gtb->status = 0; + gtb->compare = 0; + gtb->inc = 0; + } + a9_gtimer_update(s, false); +} + +static void a9_gtimer_realize(DeviceState *dev, Error **errp) +{ + A9GTimerState *s = A9_GTIMER(dev); + SysBusDevice *sbd = SYS_BUS_DEVICE(dev); + int i; + + if (s->num_cpu < 1 || s->num_cpu > A9_GTIMER_MAX_CPUS) { + error_setg(errp, "%s: num-cpu must be between 1 and %d", + __func__, A9_GTIMER_MAX_CPUS); + return; + } + + memory_region_init_io(&s->iomem, OBJECT(dev), &a9_gtimer_this_ops, s, + "a9gtimer shared", 0x20); + sysbus_init_mmio(sbd, &s->iomem); + s->timer = timer_new_ns(QEMU_CLOCK_VIRTUAL, a9_gtimer_update_no_sync, s); + + for (i = 0; i < s->num_cpu; i++) { + A9GTimerPerCPU *gtb = &s->per_cpu[i]; + + gtb->parent = s; + sysbus_init_irq(sbd, >b->irq); + memory_region_init_io(>b->iomem, OBJECT(dev), &a9_gtimer_ops, gtb, + "a9gtimer per cpu", 0x20); + sysbus_init_mmio(sbd, >b->iomem); + } +} + +static const VMStateDescription vmstate_a9_gtimer_per_cpu = { + .name = "arm.cortex-a9-global-timer.percpu", + .version_id = 1, + .minimum_version_id = 1, + .fields = (VMStateField[]) { + VMSTATE_UINT32(control, A9GTimerPerCPU), + VMSTATE_UINT64(compare, A9GTimerPerCPU), + VMSTATE_UINT32(status, A9GTimerPerCPU), + VMSTATE_UINT32(inc, A9GTimerPerCPU), + VMSTATE_END_OF_LIST() + } +}; + +static const VMStateDescription vmstate_a9_gtimer = { + .name = "arm.cortex-a9-global-timer", + .version_id = 1, + .minimum_version_id = 1, + .fields = (VMStateField[]) { + VMSTATE_TIMER_PTR(timer, A9GTimerState), + VMSTATE_UINT64(counter, A9GTimerState), + VMSTATE_UINT64(ref_counter, A9GTimerState), + VMSTATE_UINT64(cpu_ref_time, A9GTimerState), + VMSTATE_STRUCT_VARRAY_UINT32(per_cpu, A9GTimerState, num_cpu, + 1, vmstate_a9_gtimer_per_cpu, + A9GTimerPerCPU), + VMSTATE_END_OF_LIST() + } +}; + +static Property a9_gtimer_properties[] = { + DEFINE_PROP_UINT32("num-cpu", A9GTimerState, num_cpu, 0), + DEFINE_PROP_END_OF_LIST() +}; + +static void a9_gtimer_class_init(ObjectClass *klass, void *data) +{ + DeviceClass *dc = DEVICE_CLASS(klass); + + dc->realize = a9_gtimer_realize; + dc->vmsd = &vmstate_a9_gtimer; + dc->reset = a9_gtimer_reset; + dc->props = a9_gtimer_properties; +} + +static const TypeInfo a9_gtimer_info = { + .name = TYPE_A9_GTIMER, + .parent = TYPE_SYS_BUS_DEVICE, + .instance_size = sizeof(A9GTimerState), + .class_init = a9_gtimer_class_init, +}; + +static void a9_gtimer_register_types(void) +{ + type_register_static(&a9_gtimer_info); +} + +type_init(a9_gtimer_register_types) |
