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authorYang Zhang <yang.z.zhang@intel.com>2015-08-28 09:58:54 +0800
committerYang Zhang <yang.z.zhang@intel.com>2015-09-01 12:44:00 +0800
commite44e3482bdb4d0ebde2d8b41830ac2cdb07948fb (patch)
tree66b09f592c55df2878107a468a91d21506104d3f /qemu/hw/openrisc/cputimer.c
parent9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00 (diff)
Add qemu 2.4.0
Change-Id: Ic99cbad4b61f8b127b7dc74d04576c0bcbaaf4f5 Signed-off-by: Yang Zhang <yang.z.zhang@intel.com>
Diffstat (limited to 'qemu/hw/openrisc/cputimer.c')
-rw-r--r--qemu/hw/openrisc/cputimer.c112
1 files changed, 112 insertions, 0 deletions
diff --git a/qemu/hw/openrisc/cputimer.c b/qemu/hw/openrisc/cputimer.c
new file mode 100644
index 000000000..9c5494510
--- /dev/null
+++ b/qemu/hw/openrisc/cputimer.c
@@ -0,0 +1,112 @@
+/*
+ * QEMU OpenRISC timer support
+ *
+ * Copyright (c) 2011-2012 Jia Liu <proljc@gmail.com>
+ * Zhizhou Zhang <etouzh@gmail.com>
+ *
+ * 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/>.
+ */
+
+#include "cpu.h"
+#include "hw/hw.h"
+#include "qemu/timer.h"
+
+#define TIMER_FREQ (20 * 1000 * 1000) /* 20MHz */
+
+/* The time when TTCR changes */
+static uint64_t last_clk;
+static int is_counting;
+
+void cpu_openrisc_count_update(OpenRISCCPU *cpu)
+{
+ uint64_t now;
+
+ if (!is_counting) {
+ return;
+ }
+ now = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
+ cpu->env.ttcr += (uint32_t)muldiv64(now - last_clk, TIMER_FREQ,
+ get_ticks_per_sec());
+ last_clk = now;
+}
+
+void cpu_openrisc_timer_update(OpenRISCCPU *cpu)
+{
+ uint32_t wait;
+ uint64_t now, next;
+
+ if (!is_counting) {
+ return;
+ }
+
+ cpu_openrisc_count_update(cpu);
+ now = last_clk;
+
+ if ((cpu->env.ttmr & TTMR_TP) <= (cpu->env.ttcr & TTMR_TP)) {
+ wait = TTMR_TP - (cpu->env.ttcr & TTMR_TP) + 1;
+ wait += cpu->env.ttmr & TTMR_TP;
+ } else {
+ wait = (cpu->env.ttmr & TTMR_TP) - (cpu->env.ttcr & TTMR_TP);
+ }
+ next = now + muldiv64(wait, get_ticks_per_sec(), TIMER_FREQ);
+ timer_mod(cpu->env.timer, next);
+}
+
+void cpu_openrisc_count_start(OpenRISCCPU *cpu)
+{
+ is_counting = 1;
+ cpu_openrisc_count_update(cpu);
+}
+
+void cpu_openrisc_count_stop(OpenRISCCPU *cpu)
+{
+ timer_del(cpu->env.timer);
+ cpu_openrisc_count_update(cpu);
+ is_counting = 0;
+}
+
+static void openrisc_timer_cb(void *opaque)
+{
+ OpenRISCCPU *cpu = opaque;
+
+ if ((cpu->env.ttmr & TTMR_IE) &&
+ timer_expired(cpu->env.timer, qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL))) {
+ CPUState *cs = CPU(cpu);
+
+ cpu->env.ttmr |= TTMR_IP;
+ cs->interrupt_request |= CPU_INTERRUPT_TIMER;
+ }
+
+ switch (cpu->env.ttmr & TTMR_M) {
+ case TIMER_NONE:
+ break;
+ case TIMER_INTR:
+ cpu->env.ttcr = 0;
+ break;
+ case TIMER_SHOT:
+ cpu_openrisc_count_stop(cpu);
+ break;
+ case TIMER_CONT:
+ break;
+ }
+
+ cpu_openrisc_timer_update(cpu);
+}
+
+void cpu_openrisc_clock_init(OpenRISCCPU *cpu)
+{
+ cpu->env.timer = timer_new_ns(QEMU_CLOCK_VIRTUAL, &openrisc_timer_cb, cpu);
+ cpu->env.ttmr = 0x00000000;
+ cpu->env.ttcr = 0x00000000;
+}