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Re: [Qemu-devel] [PATCH V3 2/4] Implement the timers on the FreeScale i.
From: |
Peter Maydell |
Subject: |
Re: [Qemu-devel] [PATCH V3 2/4] Implement the timers on the FreeScale i.MX31 SoC. This is not a complete implementation, but gives enough for Linux to boot and run. |
Date: |
Thu, 1 Dec 2011 17:11:40 +0000 |
On 30 November 2011 03:36, Peter Chubb <address@hidden> wrote:
>
> Signed-off-by: Hans Jang <address@hidden>
> Signed-off-by: Adam Clench <address@hidden>
> Signed-off-by: Peter Chubb <address@hidden>
> ---
> Makefile.target | 2
> hw/imx_timer.c | 460
> ++++++++++++++++++++++++++++++++++++++++++++++++++++++++
> 2 files changed, 461 insertions(+), 1 deletion(-)
> create mode 100644 hw/imx_timer.c
>
> Index: qemu-working/hw/imx_timer.c
> ===================================================================
> --- /dev/null 1970-01-01 00:00:00.000000000 +0000
> +++ qemu-working/hw/imx_timer.c 2011-11-30 13:38:25.818785258 +1100
> @@ -0,0 +1,460 @@
> +/*
> + * IMX31 Timer
> + *
> + * Copyright (c) 2008 OKL
> + * Copyright (c) 2011 NICTA Pty Ltd
> + * Originally Written by Hans Jiang
> + * Updated by Peter Chubb
> + *
> + * This code is licenced under GPL version 2 or later. See
> + * the COPYING file in the top-level directory.
> + */
> +
> +#include "hw.h"
> +#include "qemu-timer.h"
> +#include "sysbus.h"
> +
> +//#define DEBUG_TIMER 1
> +
> +#ifdef DEBUG_TIMER
> +# define DPRINTF(fmt, args...) \
> + do { printf("imx_timer: " fmt , ##args); } while (0)
> +#else
> +# define DPRINTF(fmt, args...) do {} while (0)
> +#endif
> +
> +/*
> + * Define to 1 for messages about attempts to
> + * access unimplemented registers or similar.
> + */
> +#define DEBUG_IMPLEMENTATION 1
> +#if DEBUG_IMPLEMENTATION
> +# define IPRINTF(fmt, args...) \
> + do { fprintf(stderr, "imx_timer: " fmt, ##args); } while (0)
> +#else
> +# define IPRINTF(fmt, args...) do {} while (0)
> +#endif
> +
> +/*
> + * GPT : General purpose timer
> + */
> +
> +#define TIMER_MAX 0xFFFFFFFFUL
> +#define GPT_FREQ 50000000 /* Hz == 50 MHz */
> +
> +/* Control register. Not all of these bits have any effect (yet) */
> +#define GPT_CR_EN (1 << 0) /* GPT Enable */
> +#define GPT_CR_ENMODE (1 << 1) /* GPT Enable Mode */
> +#define GPT_CR_DBGEN (1 << 2) /* GPT Debug mode enable */
> +#define GPT_CR_WAITEN (1 << 3) /* GPT Wait Mode Enable */
> +#define GPT_CR_DOZEN (1 << 4) /* GPT Doze mode enable */
> +#define GPT_CR_STOPEN (1 << 5) /* GPT Stop Mode Enable */
> +#define GPT_CR_CLKSRC (7 << 6) /* Clock source select (3 bits) */
> +#define GPT_CR_FRR (1 << 9) /* Freerun or Restart */
> +#define GPT_CR_SWR (1 << 15)
> +#define GPT_CR_IM1 (3 << 16) /* Input capture channel 1 mode (2 bits) */
> +#define GPT_CR_IM2 (3 << 18) /* Input capture channel 2 mode (2 bits) */
> +#define GPT_CR_OM1 (7 << 20) /* Output Compare Channel 1 Mode (3 bits) */
> +#define GPT_CR_OM2 (7 << 23) /* Output Compare Channel 2 Mode (3 bits) */
> +#define GPT_CR_OM3 (7 << 26) /* Output Compare Channel 3 Mode (3 bits) */
> +#define GPT_CR_FO1 (1 << 29) /* Force Output Compare Channel 1 */
> +#define GPT_CR_FO2 (1 << 30) /* Force Output Compare Channel 2 */
> +#define GPT_CR_FO3 (1 << 31) /* Force Output Compare Channel 3 */
> +
> +#define GPT_SR_OF1 (1 << 0)
> +#define GPT_SR_ROV (1 << 5)
> +
> +#define GPT_IR_OF1IE (1 << 0)
> +#define GPT_IR_ROVIE (1 << 5)
> +
> +typedef struct {
> + SysBusDevice busdev;
> + QEMUTimer *timer;
> + MemoryRegion iomem;
> + uint32_t cr;
> + uint32_t sr;
> + uint32_t pr;
> + uint32_t ir;
> + uint32_t ocr1;
> + uint32_t cnt;
> +
> + int waiting_rov;
> + qemu_irq irq;
> +} imxg_timer_state;
> +
> +static const VMStateDescription vmstate_imxg_timer = {
> + .name = "imxg-timer",
> + .version_id = 1,
> + .minimum_version_id = 1,
> + .minimum_version_id_old = 1,
> + .fields = (VMStateField[]) {
> + VMSTATE_UINT32(cr, imxg_timer_state),
> + VMSTATE_UINT32(sr, imxg_timer_state),
> + VMSTATE_UINT32(ir, imxg_timer_state),
> + VMSTATE_UINT32(cnt, imxg_timer_state),
> + VMSTATE_UINT32(ocr1, imxg_timer_state),
> + VMSTATE_TIMER(timer, imxg_timer_state),
Missing 'pr' and 'waiting_rov' ?
> + VMSTATE_END_OF_LIST()
> + }
> +};
> +
> +
> +/* Check all active timers, and schedule the next timer interrupt. */
> +static void imxg_timer_update(imxg_timer_state *s)
> +{
> + uint32_t flags = s->sr & s->ir & (GPT_SR_OF1 | GPT_SR_ROV);
> +
> + if ((s->cr & GPT_CR_EN) && flags) {
> + qemu_irq_raise(s->irq);
> + } else {
> + qemu_irq_lower(s->irq);
> + }
> +}
> +
> +static uint64_t imxg_timer_update_count(imxg_timer_state *s)
> +{
> + uint64_t clk = qemu_get_clock_ns(vm_clock);
> +
> + s->cnt = ((uint32_t)muldiv64(clk, GPT_FREQ/1000000,
> + 1000)) % TIMER_MAX;
> + return clk;
> +}
> +
> +static void imxg_timer_run(imxg_timer_state *s, uint32_t timeout)
> +{
> + uint64_t clk = imxg_timer_update_count(s);
> + uint32_t diff_cnt;
> + if (s->cnt < timeout) {
> + diff_cnt = (timeout - s->cnt);
> + s->waiting_rov = 0;
> + } else {
> + diff_cnt = (TIMER_MAX - s->cnt);
> + s->waiting_rov = 1;
> + }
> + qemu_mod_timer(s->timer, clk + diff_cnt * 1000 / (GPT_FREQ/1000000));
You haven't explained why this uses raw qemu timers but
the enhanced timer later in the file uses ptimers, why
doing a % 0xffffffff makes sense, etc.
Stopped review here.
> +}
> +
> +static uint64_t imxg_timer_read(void *opaque, target_phys_addr_t offset,
> + unsigned size)
> +{
> + imxg_timer_state *s = (imxg_timer_state *)opaque;
> +
> + DPRINTF("g-read(offset=%x)\n", offset >> 2);
> + switch (offset >> 2) {
> + case 0: /* CR */
> + return s->cr;
> +
> + case 1: /* prescaler */
> + return s->pr;
> +
> + case 2:
> + return s->sr;
> +
> + case 3:
> + return s->ir;
> +
> + case 4:
> + return s->ocr1;
> +
> + case 9: /* cnt */
> + imxg_timer_update_count(s);
> + return s->cnt;
> + }
> +
> + IPRINTF("imxg_timer_read: Bad offset %x\n",
> + (int)offset >> 2);
> + return 0;
> +}
> +
> +static void imxg_timer_reset(DeviceState *dev)
> +{
> + imxg_timer_state *s = container_of(dev, imxg_timer_state, busdev.qdev);
> +
> + s->cr &= ~(GPT_CR_EN|GPT_CR_DOZEN|GPT_CR_WAITEN|GPT_CR_DBGEN);
> + s->sr = 0;
> + s->pr = 0;
> + s->ir = 0;
> + s->cnt = 0;
> + s->ocr1 = 0;
> + imxg_timer_update_count(s);
> + imxg_timer_update(s);
> +}
> +
> +static void imxg_timer_write(void *opaque, target_phys_addr_t offset,
> + uint64_t value, unsigned size)
> +{
> + imxg_timer_state *s = (imxg_timer_state *)opaque;
> + DPRINTF("g-write(offset=%x, value = %x)\n", (unsigned int)offset >> 2,
> + (unsigned int)value);
> +
> + switch (offset >> 2) {
> + case 0: /* CR */
> + if (value & GPT_CR_SWR) { /* force reset */
> + value &= ~GPT_CR_SWR;
> + imxg_timer_reset(&s->busdev.qdev);
> + }
> + if (!(s->cr & GPT_CR_EN) && (value & GPT_CR_EN)) {
> + if (value & GPT_CR_ENMODE) {
> + s->cnt = 0;
> + }
> + imxg_timer_run(s, s->ocr1);
> + } else if ((s->cr & GPT_CR_EN) && !(value & GPT_CR_EN)) {
> + qemu_del_timer(s->timer);
> + };
> + s->cr = value;
> + return;
> +
> + case 1:
> + s->pr = value;
> + return;
> +
> + case 2:
> + if (value & GPT_SR_OF1) {
> + s->sr &= ~GPT_SR_OF1;
> + }
> + if (value & GPT_SR_ROV) {
> + s->sr &= ~GPT_SR_ROV;
> + }
> + imxg_timer_update(s);
> + return;
> +
> + case 3:
> + s->ir = value;
> + imxg_timer_update(s);
> + return;
> +
> + case 4:
> + s->ocr1 = value;
> + if (s->cr & GPT_CR_EN) {
> + imxg_timer_run(s, s->ocr1);
> + }
> + return;
> +
> + default:
> + IPRINTF("imxg_timer_write: Bad offset %x\n",
> + (int)offset >> 2);
> + }
> +}
> +
> +static void imxg_timer_timeout(void *opaque)
> +{
> + imxg_timer_state *s = (imxg_timer_state *)opaque;
> +
> + DPRINTF("imxg_timer_timeout\n");
> + if (s->waiting_rov) {
> + s->sr |= GPT_SR_ROV;
> + imxg_timer_run(s, s->ocr1);
> + } else {
> + s->sr |= GPT_SR_OF1;
> + imxg_timer_run(s, 0);
> + }
> + imxg_timer_update(s);
> +}
> +
> +static const MemoryRegionOps imxg_timer_ops = {
> + .read = imxg_timer_read,
> + .write = imxg_timer_write,
> + .endianness = DEVICE_NATIVE_ENDIAN,
> +};
> +
> +
> +static int imxg_timer_init(SysBusDevice *dev)
> +{
> + imxg_timer_state *s = FROM_SYSBUS(imxg_timer_state, dev);
> +
> + sysbus_init_irq(dev, &s->irq);
> + memory_region_init_io(&s->iomem, &imxg_timer_ops,
> + s, "imxg-timer",
> + 0x00001000);
> + sysbus_init_mmio_region(dev, &s->iomem);
> +
> + s->timer = qemu_new_timer_ns(vm_clock, imxg_timer_timeout, s);
> + imxg_timer_reset(&dev->qdev);
> + return 0;
> +}
> +
> +
> +
> +/*
> + * EPIT :Enhanced periodic interrupt timer
> + */
> +
> +#define EPIT_FREQ 1000000
> +#define TIMER_TICK_LENGTH 5000
> +#define IMX31_TICKS_PER_TIMESLICE (72 * TIMER_TICK_LENGTH)
> +#define CR_EN (1 << 0)
> +#define CR_SWR (1 << 16)
> +
> +typedef struct {
> + SysBusDevice busdev;
> + ptimer_state *timer;
> + MemoryRegion iomem;
> + uint32_t cr;
> + uint32_t lr;
> + uint32_t cmp;
> + int int_level;
> + qemu_irq irq;
> +} imxp_timer_state;
> +
> +/* Check all active timers, and schedule the next timer interrupt. */
> +static void imxp_timer_update(imxp_timer_state *s)
> +{
> + /* Update interrupts. */
> + if (s->int_level && (s->cr & CR_EN)) {
> + qemu_irq_raise(s->irq);
> + } else {
> + qemu_irq_lower(s->irq);
> + }
> +}
> +
> +static void imxp_timer_reset(DeviceState *dev)
> +{
> + imxp_timer_state *s = container_of(dev, imxp_timer_state, busdev.qdev);
> +
> + s->cr = 0;
> + s->lr = 0;
> + ptimer_stop(s->timer);
> +}
> +
> +static uint64_t imxp_timer_read(void *opaque, target_phys_addr_t offset,
> + unsigned size)
> +{
> + imxp_timer_state *s = (imxp_timer_state *)opaque;
> +
> + DPRINTF("p-read(offset=%x)\n", offset);
> + switch (offset >> 2) {
> + case 0: /* CR */
> + return s->cr;
> +
> + case 1: /* SR */
> + return s->int_level;
> +
> + case 2: /* LR - set ticks*/
> + return s->lr;
> +
> + case 3: /* CMP */
> + return s->cmp;
> +
> + case 4: /* CNT */
> + return ptimer_get_count(s->timer);
> + }
> + IPRINTF("imxp_timer_read: Bad offset %x\n",
> + (int)offset >> 2);
> + return 0;
> +}
> +
> +static void imxp_timer_write(void *opaque, target_phys_addr_t offset,
> + uint64_t value, unsigned size)
> +{
> + imxp_timer_state *s = (imxp_timer_state *)opaque;
> + DPRINTF("p-write(offset=%x, value = %x)\n", (unsigned int)offset >> 2,
> + (unsigned int)value);
> +
> + switch (offset >> 2) {
> + case 0: /* CR */
> + s->cr = value;
> + if (s->cr & CR_EN) {
> + ptimer_run(s->timer, 0);
> + } else {
> + ptimer_stop(s->timer);
> + }
> + if (s->cr & CR_SWR) {
> + imxp_timer_reset(&s->busdev.qdev);
> + }
> + break;
> +
> + case 1: /* SR - ACK*/
> + s->int_level = 0;
> + imxp_timer_update(s);
> + break;
> +
> + case 2: /* LR - set ticks*/
> + s->lr = value;
> + ptimer_set_freq(s->timer, EPIT_FREQ);
> + ptimer_set_limit(s->timer, value, 1);
> + break;
> +
> + case 3: /* CMP */
> + s->cmp = value;
> + break;
> +
> + default:
> + IPRINTF("imxp_timer_write: Bad offset %x\n",
> + (int)offset >> 2);
> + }
> +}
> +
> +static void imxp_timer_tick(void *opaque)
> +{
> + imxp_timer_state *s = (imxp_timer_state *)opaque;
> + s->int_level = 1;
> + imxp_timer_update(s);
> +}
> +
> +static const MemoryRegionOps imxp_timer_ops = {
> + .read = imxp_timer_read,
> + .write = imxp_timer_write,
> + .endianness = DEVICE_NATIVE_ENDIAN,
> +};
> +
> +static const VMStateDescription vmstate_imxp_timer = {
> + .name = "imxp-timer",
> + .version_id = 1,
> + .minimum_version_id = 1,
> + .minimum_version_id_old = 1,
> + .fields = (VMStateField[]) {
> + VMSTATE_UINT32(cr, imxp_timer_state),
> + VMSTATE_UINT32(lr, imxp_timer_state),
> + VMSTATE_UINT32(cmp, imxp_timer_state),
> + VMSTATE_INT32(int_level, imxp_timer_state),
> + VMSTATE_PTIMER(timer, imxp_timer_state),
> + VMSTATE_END_OF_LIST()
> + }
> +};
> +
> +static int imxp_timer_init(SysBusDevice *dev)
> +{
> + imxp_timer_state *s = FROM_SYSBUS(imxp_timer_state, dev);
> + QEMUBH *bh;
> +
> + DPRINTF("imxp_timer_init\n");
> +
> + sysbus_init_irq(dev, &s->irq);
> + memory_region_init_io(&s->iomem, &imxp_timer_ops,
> + s, "imxp-timer",
> + 0x00001000);
> + sysbus_init_mmio_region(dev, &s->iomem);
> +
> + bh = qemu_bh_new(imxp_timer_tick, s);
> + s->timer = ptimer_init(bh);
> + imxp_timer_reset(&s->busdev.qdev);
> +
> + return 0;
> +}
> +
> +static SysBusDeviceInfo imx_timerp_info = {
> + .qdev.name = "imx_timerp",
> + .qdev.desc = "i.MX Periodic Timer",
> + .qdev.size = sizeof (imxp_timer_state),
> + .qdev.vmsd = &vmstate_imxp_timer,
> + .qdev.reset = imxp_timer_reset,
> + .init = imxp_timer_init,
> +
> +};
> +
> +static SysBusDeviceInfo imx_timerg_info = {
> + .qdev.name = "imx_timerg",
> + .qdev.desc = "i.MX General Timer",
> + .qdev.size = sizeof (imxg_timer_state),
> + .qdev.vmsd = &vmstate_imxg_timer,
> + .qdev.reset = imxg_timer_reset,
> + .init = imxg_timer_init,
> +};
> +
> +static void imx_timer_register_devices(void)
> +{
> + sysbus_register_withprop(&imx_timerp_info);
> + sysbus_register_withprop(&imx_timerg_info);
> +}
> +
> +device_init(imx_timer_register_devices)
> Index: qemu-working/Makefile.target
> ===================================================================
> --- qemu-working.orig/Makefile.target 2011-11-30 13:38:24.786779925 +1100
> +++ qemu-working/Makefile.target 2011-11-30 13:38:25.818785258 +1100
> @@ -361,21 +361,21 @@ obj-arm-y += mst_fpga.o mainstone.o
> obj-arm-y += z2.o
> obj-arm-y += musicpal.o bitbang_i2c.o marvell_88w8618_audio.o
> obj-arm-y += framebuffer.o
> obj-arm-y += syborg.o syborg_fb.o syborg_interrupt.o syborg_keyboard.o
> obj-arm-y += syborg_serial.o syborg_timer.o syborg_pointer.o syborg_rtc.o
> obj-arm-y += syborg_virtio.o
> obj-arm-y += vexpress.o
> obj-arm-y += strongarm.o
> obj-arm-y += collie.o
> obj-arm-y += pl041.o lm4549.o
> -obj-arm-y += imx_serial.o
> +obj-arm-y += imx_serial.o imx_timer.o
>
> obj-sh4-y = shix.o r2d.o sh7750.o sh7750_regnames.o tc58128.o
> obj-sh4-y += sh_timer.o sh_serial.o sh_intc.o sh_pci.o sm501.o
> obj-sh4-y += ide/mmio.o
>
> obj-m68k-y = an5206.o mcf5206.o mcf_uart.o mcf_intc.o mcf5208.o mcf_fec.o
> obj-m68k-y += m68k-semi.o dummy_m68k.o
>
> obj-s390x-y = s390-virtio-bus.o s390-virtio.o
>
>
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- Re: [Qemu-devel] [PATCH V3 2/4] Implement the timers on the FreeScale i.MX31 SoC. This is not a complete implementation, but gives enough for Linux to boot and run.,
Peter Maydell <=