diff options
author | Yang Zhang <yang.z.zhang@intel.com> | 2015-08-28 09:58:54 +0800 |
---|---|---|
committer | Yang Zhang <yang.z.zhang@intel.com> | 2015-09-01 12:44:00 +0800 |
commit | e44e3482bdb4d0ebde2d8b41830ac2cdb07948fb (patch) | |
tree | 66b09f592c55df2878107a468a91d21506104d3f /qemu/hw/openrisc/cputimer.c | |
parent | 9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00 (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.c | 112 |
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; +} |