[dif/rv_timer] add function to write to counter
This adds an additional function, dif_rv_timer_counter_write(),
to fix #7921.
Signed-off-by: Timothy Trippel <ttrippel@google.com>
diff --git a/sw/device/lib/dif/dif_rv_timer.c b/sw/device/lib/dif/dif_rv_timer.c
index 3d9a946..2b6051e 100644
--- a/sw/device/lib/dif/dif_rv_timer.c
+++ b/sw/device/lib/dif/dif_rv_timer.c
@@ -7,6 +7,7 @@
#include <stddef.h>
#include "sw/device/lib/base/bitfield.h"
+
#include "rv_timer_regs.h" // Generated.
/**
@@ -158,6 +159,36 @@
}
}
+dif_rv_timer_result_t dif_rv_timer_counter_write(const dif_rv_timer_t *timer,
+ uint32_t hart_id,
+ uint64_t count) {
+ if (timer == NULL || hart_id >= timer->config.hart_count) {
+ return kDifRvTimerBadArg;
+ }
+
+ // Disable the counter.
+ uint32_t ctrl_reg =
+ mmio_region_read32(timer->base_addr, RV_TIMER_CTRL_REG_OFFSET);
+ uint32_t ctrl_reg_cleared = bitfield_bit32_write(ctrl_reg, hart_id, false);
+ mmio_region_write32(timer->base_addr, RV_TIMER_CTRL_REG_OFFSET,
+ ctrl_reg_cleared);
+
+ // Write the new count.
+ uint32_t lower_count = count;
+ uint32_t upper_count = count >> 32;
+ mmio_region_write32(timer->base_addr,
+ reg_for_hart(hart_id, RV_TIMER_TIMER_V_LOWER0_REG_OFFSET),
+ lower_count);
+ mmio_region_write32(timer->base_addr,
+ reg_for_hart(hart_id, RV_TIMER_TIMER_V_UPPER0_REG_OFFSET),
+ upper_count);
+
+ // Re-enable the counter (if it was previously enabled).
+ mmio_region_write32(timer->base_addr, RV_TIMER_CTRL_REG_OFFSET, ctrl_reg);
+
+ return kDifRvTimerOk;
+}
+
dif_rv_timer_result_t dif_rv_timer_arm(const dif_rv_timer_t *timer,
uint32_t hart_id, uint32_t comp_id,
uint64_t threshold) {
diff --git a/sw/device/lib/dif/dif_rv_timer.h b/sw/device/lib/dif/dif_rv_timer.h
index 471a2df..f73b5a9 100644
--- a/sw/device/lib/dif/dif_rv_timer.h
+++ b/sw/device/lib/dif/dif_rv_timer.h
@@ -200,7 +200,7 @@
dif_rv_timer_enabled_t state);
/**
- * Reads the current value on a particlar hart's timer.
+ * Reads the current value on a particular hart's timer.
*
* @param timer A timer device.
* @param hart_id The hart counter to read.
@@ -212,6 +212,18 @@
uint64_t *out);
/**
+ * Writes the given value to a particular hart's timer.
+ *
+ * @param timer A timer device.
+ * @param hart_id The hart counter to write.
+ * @param count The counter value to write.
+ * @return The result of the operation.
+ */
+dif_rv_timer_result_t dif_rv_timer_counter_write(const dif_rv_timer_t *timer,
+ uint32_t hart_id,
+ uint64_t count);
+
+/**
* Arms the timer to go off once the counter value is greater than
* or equal to `threshold`, by setting up the given comparator.
*
diff --git a/sw/device/lib/dif/dif_rv_timer_unittest.cc b/sw/device/lib/dif/dif_rv_timer_unittest.cc
index 5291f54..6b81809 100644
--- a/sw/device/lib/dif/dif_rv_timer_unittest.cc
+++ b/sw/device/lib/dif/dif_rv_timer_unittest.cc
@@ -2,18 +2,19 @@
// Licensed under the Apache License, Version 2.0, see LICENSE for details.
// SPDX-License-Identifier: Apache-2.0
+#include "sw/device/lib/dif/dif_rv_timer.h"
+
#include <cstring>
#include <limits>
#include <ostream>
#include <stdint.h>
-#include "sw/device/lib/dif/dif_rv_timer.h"
-#include "rv_timer_regs.h" // Generated.
-
#include "gtest/gtest.h"
#include "sw/device/lib/base/mmio.h"
#include "sw/device/lib/base/testing/mock_mmio.h"
+#include "rv_timer_regs.h" // Generated.
+
// We define global namespace == and << to make `dif_i2c_timing_params_t` work
// nicely with EXPECT_EQ.
bool operator==(dif_rv_timer_tick_params_t a, dif_rv_timer_tick_params_t b) {
@@ -46,7 +47,8 @@
// The timer frequency devices the clock speed, so their quotient minus 1 is
// the prescale.
dif_rv_timer_tick_params_t params, expected = {
- .prescale = 49, .tick_step = 1,
+ .prescale = 49,
+ .tick_step = 1,
};
EXPECT_EQ(
dif_rv_timer_approximate_tick_params(kClockSpeed, kSlowTimer, ¶ms),
@@ -57,7 +59,8 @@
TEST(ApproximateParamsTest, WithStep) {
// 50 MHz / 5 is 10 MHz; multiplied by 12, we get 120 MHz.
dif_rv_timer_tick_params_t params, expected = {
- .prescale = 4, .tick_step = 12,
+ .prescale = 4,
+ .tick_step = 12,
};
EXPECT_EQ(
dif_rv_timer_approximate_tick_params(kClockSpeed, kFastTimer, ¶ms),
@@ -94,7 +97,8 @@
protected:
dif_rv_timer_t MakeTimer(dif_rv_timer_config_t config) {
return {
- .base_addr = dev().region(), .config = config,
+ .base_addr = dev().region(),
+ .config = config,
};
}
};
@@ -133,7 +137,8 @@
dif_rv_timer timer;
EXPECT_EQ(dif_rv_timer_init(dev().region(),
{
- .hart_count = 1, .comparator_count = 1,
+ .hart_count = 1,
+ .comparator_count = 1,
},
&timer),
kDifRvTimerOk);
@@ -164,7 +169,8 @@
dif_rv_timer timer;
EXPECT_EQ(dif_rv_timer_init(dev().region(),
{
- .hart_count = 1, .comparator_count = 4,
+ .hart_count = 1,
+ .comparator_count = 4,
},
&timer),
kDifRvTimerOk);
@@ -198,7 +204,8 @@
dif_rv_timer timer;
EXPECT_EQ(dif_rv_timer_init(dev().region(),
{
- .hart_count = 4, .comparator_count = 4,
+ .hart_count = 4,
+ .comparator_count = 4,
},
&timer),
kDifRvTimerOk);
@@ -207,7 +214,8 @@
TEST_F(InitTest, NullArgs) {
EXPECT_EQ(dif_rv_timer_init(dev().region(),
{
- .hart_count = 1, .comparator_count = 1,
+ .hart_count = 1,
+ .comparator_count = 1,
},
nullptr),
kDifRvTimerBadArg);
@@ -217,13 +225,15 @@
dif_rv_timer_t timer;
EXPECT_EQ(dif_rv_timer_init(dev().region(),
{
- .hart_count = 0, .comparator_count = 1,
+ .hart_count = 0,
+ .comparator_count = 1,
},
&timer),
kDifRvTimerBadArg);
EXPECT_EQ(dif_rv_timer_init(dev().region(),
{
- .hart_count = 1, .comparator_count = 0,
+ .hart_count = 1,
+ .comparator_count = 0,
},
&timer),
kDifRvTimerBadArg);
@@ -407,6 +417,34 @@
EXPECT_EQ(dif_rv_timer_counter_read(&timer, 5, &value), kDifRvTimerBadArg);
}
+class CounterWriteTest : public TimerTest {};
+
+TEST_F(CounterWriteTest, Baseline) {
+ EXPECT_READ32(RV_TIMER_CTRL_REG_OFFSET, 0x0000'0001);
+ EXPECT_WRITE32(RV_TIMER_CTRL_REG_OFFSET, 0x0000'0000);
+ EXPECT_WRITE32(RegForHart(0, RV_TIMER_TIMER_V_LOWER0_REG_OFFSET),
+ 0xDEAD'BEEF);
+ EXPECT_WRITE32(RegForHart(0, RV_TIMER_TIMER_V_UPPER0_REG_OFFSET),
+ 0xCAFE'FEED);
+ EXPECT_WRITE32(RV_TIMER_CTRL_REG_OFFSET, 0x0000'0001);
+
+ auto timer = MakeTimer({1, 1});
+ uint64_t count = 0xCAFE'FEED'DEAD'BEEF;
+ EXPECT_EQ(dif_rv_timer_counter_write(&timer, 0, count), kDifRvTimerOk);
+}
+
+TEST_F(CounterWriteTest, NullArgs) {
+ uint64_t count = 0xCAFE'FEED'DEAD'BEEF;
+ EXPECT_EQ(dif_rv_timer_counter_write(nullptr, 0, count), kDifRvTimerBadArg);
+}
+
+TEST_F(CounterWriteTest, BadHart) {
+ auto timer = MakeTimer({1, 1});
+ uint64_t count = 0xCAFE'FEED'DEAD'BEEF;
+ EXPECT_EQ(dif_rv_timer_counter_write(&timer, 1, count), kDifRvTimerBadArg);
+ EXPECT_EQ(dif_rv_timer_counter_write(&timer, 2, count), kDifRvTimerBadArg);
+}
+
class ArmTest : public TimerTest {};
TEST_F(ArmTest, Baseline) {
