qemu-e2k/hw/xilinx_timer.c

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/*
* QEMU model of the Xilinx timer block.
*
* Copyright (c) 2009 Edgar E. Iglesias.
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
#include "sysbus.h"
#include "sysemu.h"
#include "qemu-timer.h"
#define D(x)
#define R_TCSR 0
#define R_TLR 1
#define R_TCR 2
#define R_MAX 4
#define TCSR_MDT (1<<0)
#define TCSR_UDT (1<<1)
#define TCSR_GENT (1<<2)
#define TCSR_CAPT (1<<3)
#define TCSR_ARHT (1<<4)
#define TCSR_LOAD (1<<5)
#define TCSR_ENIT (1<<6)
#define TCSR_ENT (1<<7)
#define TCSR_TINT (1<<8)
#define TCSR_PWMA (1<<9)
#define TCSR_ENALL (1<<10)
struct xlx_timer
{
QEMUBH *bh;
ptimer_state *ptimer;
void *parent;
int nr; /* for debug. */
unsigned long timer_div;
uint32_t regs[R_MAX];
};
struct timerblock
{
SysBusDevice busdev;
qemu_irq irq;
unsigned int nr_timers;
struct xlx_timer *timers;
};
static inline unsigned int timer_from_addr(target_phys_addr_t addr)
{
/* Timers get a 4x32bit control reg area each. */
return addr >> 2;
}
static void timer_update_irq(struct timerblock *t)
{
unsigned int i, irq = 0;
uint32_t csr;
for (i = 0; i < t->nr_timers; i++) {
csr = t->timers[i].regs[R_TCSR];
irq |= (csr & TCSR_TINT) && (csr & TCSR_ENIT);
}
/* All timers within the same slave share a single IRQ line. */
qemu_set_irq(t->irq, !!irq);
}
static uint32_t timer_readl (void *opaque, target_phys_addr_t addr)
{
struct timerblock *t = opaque;
struct xlx_timer *xt;
uint32_t r = 0;
unsigned int timer;
addr >>= 2;
timer = timer_from_addr(addr);
xt = &t->timers[timer];
/* Further decoding to address a specific timers reg. */
addr &= 0x3;
switch (addr)
{
case R_TCR:
r = ptimer_get_count(xt->ptimer);
if (!(xt->regs[R_TCSR] & TCSR_UDT))
r = ~r;
D(qemu_log("xlx_timer t=%d read counter=%x udt=%d\n",
timer, r, xt->regs[R_TCSR] & TCSR_UDT));
break;
default:
if (addr < ARRAY_SIZE(xt->regs))
r = xt->regs[addr];
break;
}
D(printf("%s timer=%d %x=%x\n", __func__, timer, addr * 4, r));
return r;
}
static void timer_enable(struct xlx_timer *xt)
{
uint64_t count;
D(printf("%s timer=%d down=%d\n", __func__,
xt->nr, xt->regs[R_TCSR] & TCSR_UDT));
ptimer_stop(xt->ptimer);
if (xt->regs[R_TCSR] & TCSR_UDT)
count = xt->regs[R_TLR];
else
count = ~0 - xt->regs[R_TLR];
ptimer_set_count(xt->ptimer, count);
ptimer_run(xt->ptimer, 1);
}
static void
timer_writel (void *opaque, target_phys_addr_t addr, uint32_t value)
{
struct timerblock *t = opaque;
struct xlx_timer *xt;
unsigned int timer;
addr >>= 2;
timer = timer_from_addr(addr);
xt = &t->timers[timer];
D(printf("%s addr=%x val=%x (timer=%d off=%d)\n",
__func__, addr * 4, value, timer, addr & 3));
/* Further decoding to address a specific timers reg. */
addr &= 3;
switch (addr)
{
case R_TCSR:
if (value & TCSR_TINT)
value &= ~TCSR_TINT;
xt->regs[addr] = value;
if (value & TCSR_ENT)
timer_enable(xt);
break;
default:
if (addr < ARRAY_SIZE(xt->regs))
xt->regs[addr] = value;
break;
}
timer_update_irq(t);
}
static CPUReadMemoryFunc *timer_read[] = {
NULL, NULL,
&timer_readl,
};
static CPUWriteMemoryFunc *timer_write[] = {
NULL, NULL,
&timer_writel,
};
static void timer_hit(void *opaque)
{
struct xlx_timer *xt = opaque;
struct timerblock *t = xt->parent;
D(printf("%s %d\n", __func__, timer));
xt->regs[R_TCSR] |= TCSR_TINT;
if (xt->regs[R_TCSR] & TCSR_ARHT)
timer_enable(xt);
timer_update_irq(t);
}
static void xilinx_timer_init(SysBusDevice *dev)
{
struct timerblock *t = FROM_SYSBUS(typeof (*t), dev);
unsigned int i;
int timer_regs, freq_hz;
/* All timers share a single irq line. */
sysbus_init_irq(dev, &t->irq);
/* Init all the ptimers. */
freq_hz = qdev_get_prop_int(&dev->qdev, "frequency", 2);
t->nr_timers = qdev_get_prop_int(&dev->qdev, "nr-timers", 2);
t->timers = qemu_mallocz(sizeof t->timers[0] * t->nr_timers);
for (i = 0; i < t->nr_timers; i++) {
struct xlx_timer *xt = &t->timers[i];
xt->parent = t;
xt->nr = i;
xt->bh = qemu_bh_new(timer_hit, xt);
xt->ptimer = ptimer_init(xt->bh);
ptimer_set_freq(xt->ptimer, freq_hz);
}
timer_regs = cpu_register_io_memory(0, timer_read, timer_write, t);
sysbus_init_mmio(dev, R_MAX * 4 * t->nr_timers, timer_regs);
}
static void xilinx_timer_register(void)
{
sysbus_register_dev("xilinx,timer", sizeof (struct timerblock),
xilinx_timer_init);
}
device_init(xilinx_timer_register)