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authorPeter Maydell <peter.maydell@linaro.org>2018-08-24 13:17:40 +0100
committerPeter Maydell <peter.maydell@linaro.org>2018-08-24 13:17:40 +0100
commita1982f90a42b22f2858e7d8497ab7223cd49b65d (patch)
treed4e99b6cab3fb3833247c95de02befca30765da0 /hw/misc/mps2-fpgaio.c
parent299953b989878d8f9ea38c7ea2d6760d49c0325e (diff)
downloadqemu-arm-a1982f90a42b22f2858e7d8497ab7223cd49b65d.tar.gz
hw/misc/mps2-fpgaio: Implement 1Hz and 100Hz counters
The MPS2 FPGAIO block includes some simple free-running counters. Implement these. Signed-off-by: Peter Maydell <peter.maydell@linaro.org> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Message-id: 20180820141116.9118-2-peter.maydell@linaro.org
Diffstat (limited to 'hw/misc/mps2-fpgaio.c')
-rw-r--r--hw/misc/mps2-fpgaio.c53
1 files changed, 52 insertions, 1 deletions
diff --git a/hw/misc/mps2-fpgaio.c b/hw/misc/mps2-fpgaio.c
index 7394a057d8..bbc28f641f 100644
--- a/hw/misc/mps2-fpgaio.c
+++ b/hw/misc/mps2-fpgaio.c
@@ -22,6 +22,7 @@
#include "hw/sysbus.h"
#include "hw/registerfields.h"
#include "hw/misc/mps2-fpgaio.h"
+#include "qemu/timer.h"
REG32(LED0, 0)
REG32(BUTTON, 8)
@@ -32,10 +33,21 @@ REG32(PRESCALE, 0x1c)
REG32(PSCNTR, 0x20)
REG32(MISC, 0x4c)
+static uint32_t counter_from_tickoff(int64_t now, int64_t tick_offset, int frq)
+{
+ return muldiv64(now - tick_offset, frq, NANOSECONDS_PER_SECOND);
+}
+
+static int64_t tickoff_from_counter(int64_t now, uint32_t count, int frq)
+{
+ return now - muldiv64(count, NANOSECONDS_PER_SECOND, frq);
+}
+
static uint64_t mps2_fpgaio_read(void *opaque, hwaddr offset, unsigned size)
{
MPS2FPGAIO *s = MPS2_FPGAIO(opaque);
uint64_t r;
+ int64_t now;
switch (offset) {
case A_LED0:
@@ -54,10 +66,15 @@ static uint64_t mps2_fpgaio_read(void *opaque, hwaddr offset, unsigned size)
r = s->misc;
break;
case A_CLK1HZ:
+ now = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
+ r = counter_from_tickoff(now, s->clk1hz_tick_offset, 1);
+ break;
case A_CLK100HZ:
+ now = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
+ r = counter_from_tickoff(now, s->clk100hz_tick_offset, 100);
+ break;
case A_COUNTER:
case A_PSCNTR:
- /* These are all upcounters of various frequencies. */
qemu_log_mask(LOG_UNIMP, "MPS2 FPGAIO: counters unimplemented\n");
r = 0;
break;
@@ -76,6 +93,7 @@ static void mps2_fpgaio_write(void *opaque, hwaddr offset, uint64_t value,
unsigned size)
{
MPS2FPGAIO *s = MPS2_FPGAIO(opaque);
+ int64_t now;
trace_mps2_fpgaio_write(offset, value, size);
@@ -100,6 +118,14 @@ static void mps2_fpgaio_write(void *opaque, hwaddr offset, uint64_t value,
"MPS2 FPGAIO: MISC control bits unimplemented\n");
s->misc = value;
break;
+ case A_CLK1HZ:
+ now = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
+ s->clk1hz_tick_offset = tickoff_from_counter(now, value, 1);
+ break;
+ case A_CLK100HZ:
+ now = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
+ s->clk100hz_tick_offset = tickoff_from_counter(now, value, 100);
+ break;
default:
qemu_log_mask(LOG_GUEST_ERROR,
"MPS2 FPGAIO write: bad offset 0x%x\n", (int) offset);
@@ -116,11 +142,14 @@ static const MemoryRegionOps mps2_fpgaio_ops = {
static void mps2_fpgaio_reset(DeviceState *dev)
{
MPS2FPGAIO *s = MPS2_FPGAIO(dev);
+ int64_t now = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
trace_mps2_fpgaio_reset();
s->led0 = 0;
s->prescale = 0;
s->misc = 0;
+ s->clk1hz_tick_offset = tickoff_from_counter(now, 0, 1);
+ s->clk100hz_tick_offset = tickoff_from_counter(now, 0, 100);
}
static void mps2_fpgaio_init(Object *obj)
@@ -133,6 +162,24 @@ static void mps2_fpgaio_init(Object *obj)
sysbus_init_mmio(sbd, &s->iomem);
}
+static bool mps2_fpgaio_counters_needed(void *opaque)
+{
+ /* Currently vmstate.c insists all subsections have a 'needed' function */
+ return true;
+}
+
+static const VMStateDescription mps2_fpgaio_counters_vmstate = {
+ .name = "mps2-fpgaio/counters",
+ .version_id = 1,
+ .minimum_version_id = 1,
+ .needed = mps2_fpgaio_counters_needed,
+ .fields = (VMStateField[]) {
+ VMSTATE_INT64(clk1hz_tick_offset, MPS2FPGAIO),
+ VMSTATE_INT64(clk100hz_tick_offset, MPS2FPGAIO),
+ VMSTATE_END_OF_LIST()
+ }
+};
+
static const VMStateDescription mps2_fpgaio_vmstate = {
.name = "mps2-fpgaio",
.version_id = 1,
@@ -142,6 +189,10 @@ static const VMStateDescription mps2_fpgaio_vmstate = {
VMSTATE_UINT32(prescale, MPS2FPGAIO),
VMSTATE_UINT32(misc, MPS2FPGAIO),
VMSTATE_END_OF_LIST()
+ },
+ .subsections = (const VMStateDescription*[]) {
+ &mps2_fpgaio_counters_vmstate,
+ NULL
}
};