Re: [Qemu-devel] [PATCH 09/17] lm32: timer model

[Blue Swirl]

On Fri, Feb 11, 2011 at 1:12 AM, Michael Walle <address@hidden> wrote:
> This patch adds support for the LatticeMico32 system timer.
>
> Signed-off-by: Michael Walle <address@hidden>
> ---
>  Makefile.target |    1 +
>  hw/lm32_timer.c |  227 
> +++++++++++++++++++++++++++++++++++++++++++++++++++++++
>  trace-events    |    6 ++
>  3 files changed, 234 insertions(+), 0 deletions(-)
>  create mode 100644 hw/lm32_timer.c
>
> diff --git a/Makefile.target b/Makefile.target
> index 7e8c5e9..e0f02cf 100644
> --- a/Makefile.target
> +++ b/Makefile.target
> @@ -251,6 +251,7 @@ obj-ppc-y += xilinx_ethlite.o
>  obj-lm32-y += lm32_pic.o
>  obj-lm32-y += lm32_pic_cpu.o
>  obj-lm32-y += lm32_juart.o
> +obj-lm32-y += lm32_timer.o
>
>  obj-mips-y = mips_r4k.o mips_jazz.o mips_malta.o mips_mipssim.o
>  obj-mips-y += mips_addr.o mips_timer.o mips_int.o
> diff --git a/hw/lm32_timer.c b/hw/lm32_timer.c
> new file mode 100644
> index 0000000..3bfc29d
> --- /dev/null
> +++ b/hw/lm32_timer.c
> @@ -0,0 +1,227 @@
> +/*
> + *  QEMU model of the LatticeMico32 timer block.
> + *
> + *  Copyright (c) 2010 Michael Walle <address@hidden>
> + *
> + * 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/>.
> + *
> + *
> + * Specification available at:
> + *   http://www.latticesemi.com/documents/mico32timer.pdf
> + */
> +
> +#include "hw.h"
> +#include "sysbus.h"
> +#include "trace.h"
> +#include "qemu-timer.h"
> +
> +#define DEFAULT_FREQUENCY (50*1000000)
> +
> +enum {
> +    R_SR = 0,
> +    R_CR,
> +    R_PERIOD,
> +    R_SNAPSHOT,
> +    R_MAX
> +};
> +
> +enum {
> +    SR_TO    = (1 << 0),
> +    SR_RUN   = (1 << 1),
> +};
> +
> +enum {
> +    CR_ITO   = (1 << 0),
> +    CR_CONT  = (1 << 1),
> +    CR_START = (1 << 2),
> +    CR_STOP  = (1 << 3),
> +};
> +
> +struct LM32TimerState {
> +    SysBusDevice busdev;
> +
> +    QEMUBH *bh;
> +    ptimer_state *ptimer;
> +
> +    qemu_irq irq;
> +    uint32_t freq_hz;
> +
> +    uint32_t regs[R_MAX];
> +};
> +typedef struct LM32TimerState LM32TimerState;
> +
> +static void timer_update_irq(LM32TimerState *s)
> +{
> +    int state = s->regs[R_SR] & SR_TO && s->regs[R_CR] & CR_ITO;

Please add parentheses so that it is clear that && is not a typo.

> +
> +    trace_lm32_timer_irq_state(state);
> +    qemu_set_irq(s->irq, state);
> +}
> +
> +static uint32_t timer_read(void *opaque, target_phys_addr_t addr)
> +{
> +    LM32TimerState *s = opaque;
> +    uint32_t r = 0;
> +
> +    addr >>= 2;
> +    switch (addr) {
> +    case R_SR:
> +    case R_CR:
> +    case R_PERIOD:
> +        r = s->regs[addr];
> +        break;
> +    case R_SNAPSHOT:
> +        r = (uint32_t)ptimer_get_count(s->ptimer);
> +        break;
> +
> +    default:
> +        hw_error("lm32_timer: read access to unkown register 0x"
> +                TARGET_FMT_plx, addr << 2);

Insecure, please fix also others.

> +        break;
> +
> +    }
> +
> +    trace_lm32_timer_memory_read(addr << 2, r);
> +    return r;
> +}
> +
> +static void timer_write(void *opaque, target_phys_addr_t addr, uint32_t 
> value)
> +{
> +    LM32TimerState *s = opaque;
> +
> +    trace_lm32_timer_memory_write(addr, value);
> +
> +    addr >>= 2;
> +    switch (addr) {
> +    case R_SR:
> +        s->regs[R_SR] &= ~SR_TO;
> +        break;
> +    case R_CR:
> +        s->regs[R_CR] = value;
> +        if (s->regs[R_CR] & CR_START) {
> +            ptimer_run(s->ptimer, 1);
> +        }
> +        if (s->regs[R_CR] & CR_STOP) {
> +            ptimer_stop(s->ptimer);
> +        }
> +        break;
> +    case R_PERIOD:
> +        s->regs[R_PERIOD] = value;
> +        ptimer_set_count(s->ptimer, value);
> +        break;
> +    case R_SNAPSHOT:
> +        hw_error("lm32_timer: write access to read only register 0x"
> +                TARGET_FMT_plx, addr << 2);
> +        break;
> +
> +    default:
> +        hw_error("lm32_timer: write access to unkown register 0x"
> +                TARGET_FMT_plx, addr << 2);
> +        break;
> +    }
> +    timer_update_irq(s);
> +}
> +
> +static CPUReadMemoryFunc * const timer_read_fn[] = {
> +    NULL,
> +    NULL,
> +    &timer_read,
> +};
> +
> +static CPUWriteMemoryFunc * const timer_write_fn[] = {
> +    NULL,
> +    NULL,
> +    &timer_write,
> +};
> +
> +static void timer_hit(void *opaque)
> +{
> +    LM32TimerState *s = opaque;
> +
> +    trace_lm32_timer_hit();
> +
> +    s->regs[R_SR] |= SR_TO;
> +
> +    if (s->regs[R_CR] & CR_CONT) {
> +        ptimer_set_count(s->ptimer, s->regs[R_PERIOD]);
> +        ptimer_run(s->ptimer, 1);
> +    }
> +
> +    timer_update_irq(s);
> +}
> +
> +static void timer_reset(void *opaque)
> +{
> +    LM32TimerState *s = opaque;
> +    int i;
> +
> +    for (i = 0; i < R_MAX; i++) {
> +        s->regs[i] = 0;
> +    }
> +    ptimer_stop(s->ptimer);
> +    qemu_irq_lower(s->irq);

Buggy, please remove.

> +}
> +
> +static int lm32_timer_init(SysBusDevice *dev)
> +{
> +    LM32TimerState *s = FROM_SYSBUS(typeof(*s), dev);
> +    int timer_regs;
> +
> +    sysbus_init_irq(dev, &s->irq);
> +
> +    s->bh = qemu_bh_new(timer_hit, s);
> +    s->ptimer = ptimer_init(s->bh);
> +    ptimer_set_freq(s->ptimer, s->freq_hz);
> +
> +    timer_regs = cpu_register_io_memory(timer_read_fn, timer_write_fn, s,
> +            DEVICE_NATIVE_ENDIAN);
> +    sysbus_init_mmio(dev, R_MAX * 4, timer_regs);
> +
> +    qemu_register_reset(timer_reset, s);

qdev reset field

> +
> +    return 0;
> +}
> +
> +static const VMStateDescription vmstate_lm32_timer = {
> +    .name = "lm32-timer",
> +    .version_id = 1,
> +    .minimum_version_id = 1,
> +    .minimum_version_id_old = 1,
> +    .fields      = (VMStateField[]) {
> +        VMSTATE_PTIMER(ptimer, LM32TimerState),
> +        VMSTATE_UINT32(freq_hz, LM32TimerState),
> +        VMSTATE_UINT32_ARRAY(regs, LM32TimerState, R_MAX),
> +        VMSTATE_END_OF_LIST()
> +    }
> +};
> +
> +static SysBusDeviceInfo lm32_timer_info = {
> +    .init = lm32_timer_init,
> +    .qdev.name  = "lm32-timer",
> +    .qdev.size  = sizeof(LM32TimerState),
> +    .qdev.vmsd  = &vmstate_lm32_timer,
> +    .qdev.props = (Property[]) {
> +        DEFINE_PROP_UINT32(
> +                "frequency", LM32TimerState, freq_hz, DEFAULT_FREQUENCY
> +        ),
> +        DEFINE_PROP_END_OF_LIST(),
> +    }
> +};
> +
> +static void lm32_timer_register(void)
> +{
> +    sysbus_register_withprop(&lm32_timer_info);
> +}
> +
> +device_init(lm32_timer_register)
> diff --git a/trace-events b/trace-events
> index 966099f..af7b27f 100644
> --- a/trace-events
> +++ b/trace-events
> @@ -269,3 +269,9 @@ disable lm32_juart_get_jtx(uint32_t value) "jtx 0x%08x"
>  disable lm32_juart_set_jtx(uint32_t value) "jtx 0x%08x"
>  disable lm32_juart_get_jrx(uint32_t value) "jrx 0x%08x"
>  disable lm32_juart_set_jrx(uint32_t value) "jrx 0x%08x"
> +
> +# hw/lm32_timer.c
> +disable lm32_timer_memory_write(uint32_t addr, uint32_t value) "addr 0x%08x 
> value 0x%08x"
> +disable lm32_timer_memory_read(uint32_t addr, uint32_t value) "addr 0x%08x 
> value 0x%08x"
> +disable lm32_timer_hit(void) "timer hit"
> +disable lm32_timer_irq_state(int level) "irq state %d"
> --
> 1.7.2.3
>
>
>