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-rw-r--r--qemu/hw/timer/imx_gpt.c557
1 files changed, 557 insertions, 0 deletions
diff --git a/qemu/hw/timer/imx_gpt.c b/qemu/hw/timer/imx_gpt.c
new file mode 100644
index 000000000..3b3101084
--- /dev/null
+++ b/qemu/hw/timer/imx_gpt.c
@@ -0,0 +1,557 @@
+/*
+ * IMX GPT Timer
+ *
+ * Copyright (c) 2008 OK Labs
+ * Copyright (c) 2011 NICTA Pty Ltd
+ * Originally written by Hans Jiang
+ * Updated by Peter Chubb
+ * Updated by Jean-Christophe Dubois
+ *
+ * This code is licensed under GPL version 2 or later. See
+ * the COPYING file in the top-level directory.
+ *
+ */
+
+#include "hw/hw.h"
+#include "qemu/bitops.h"
+#include "qemu/timer.h"
+#include "hw/ptimer.h"
+#include "hw/sysbus.h"
+#include "hw/arm/imx.h"
+#include "qemu/main-loop.h"
+
+#define TYPE_IMX_GPT "imx.gpt"
+
+/*
+ * Define to 1 for debug messages
+ */
+#define DEBUG_TIMER 0
+#if DEBUG_TIMER
+
+static char const *imx_gpt_reg_name(uint32_t reg)
+{
+ switch (reg) {
+ case 0:
+ return "CR";
+ case 1:
+ return "PR";
+ case 2:
+ return "SR";
+ case 3:
+ return "IR";
+ case 4:
+ return "OCR1";
+ case 5:
+ return "OCR2";
+ case 6:
+ return "OCR3";
+ case 7:
+ return "ICR1";
+ case 8:
+ return "ICR2";
+ case 9:
+ return "CNT";
+ default:
+ return "[?]";
+ }
+}
+
+# define DPRINTF(fmt, args...) \
+ do { printf("%s: " fmt , __func__, ##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, "%s: " fmt, __func__, ##args); } while (0)
+#else
+# define IPRINTF(fmt, args...) do {} while (0)
+#endif
+
+#define IMX_GPT(obj) \
+ OBJECT_CHECK(IMXGPTState, (obj), TYPE_IMX_GPT)
+/*
+ * GPT : General purpose timer
+ *
+ * This timer counts up continuously while it is enabled, resetting itself
+ * to 0 when it reaches GPT_TIMER_MAX (in freerun mode) or when it
+ * reaches the value of one of the ocrX (in periodic mode).
+ */
+
+#define GPT_TIMER_MAX 0XFFFFFFFFUL
+
+/* Control register. Not all of these bits have any effect (yet) */
+#define GPT_CR_EN (1 << 0) /* GPT Enable */
+#define GPT_CR_ENMOD (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_SHIFT (6)
+#define GPT_CR_CLKSRC_MASK (0x7)
+
+#define GPT_CR_FRR (1 << 9) /* Freerun or Restart */
+#define GPT_CR_SWR (1 << 15) /* Software Reset */
+#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_OF2 (1 << 1)
+#define GPT_SR_OF3 (1 << 2)
+#define GPT_SR_ROV (1 << 5)
+
+#define GPT_IR_OF1IE (1 << 0)
+#define GPT_IR_OF2IE (1 << 1)
+#define GPT_IR_OF3IE (1 << 2)
+#define GPT_IR_ROVIE (1 << 5)
+
+typedef struct {
+ SysBusDevice busdev;
+ ptimer_state *timer;
+ MemoryRegion iomem;
+ DeviceState *ccm;
+
+ uint32_t cr;
+ uint32_t pr;
+ uint32_t sr;
+ uint32_t ir;
+ uint32_t ocr1;
+ uint32_t ocr2;
+ uint32_t ocr3;
+ uint32_t icr1;
+ uint32_t icr2;
+ uint32_t cnt;
+
+ uint32_t next_timeout;
+ uint32_t next_int;
+
+ uint32_t freq;
+
+ qemu_irq irq;
+} IMXGPTState;
+
+static const VMStateDescription vmstate_imx_timer_gpt = {
+ .name = "imx.gpt",
+ .version_id = 3,
+ .minimum_version_id = 3,
+ .fields = (VMStateField[]) {
+ VMSTATE_UINT32(cr, IMXGPTState),
+ VMSTATE_UINT32(pr, IMXGPTState),
+ VMSTATE_UINT32(sr, IMXGPTState),
+ VMSTATE_UINT32(ir, IMXGPTState),
+ VMSTATE_UINT32(ocr1, IMXGPTState),
+ VMSTATE_UINT32(ocr2, IMXGPTState),
+ VMSTATE_UINT32(ocr3, IMXGPTState),
+ VMSTATE_UINT32(icr1, IMXGPTState),
+ VMSTATE_UINT32(icr2, IMXGPTState),
+ VMSTATE_UINT32(cnt, IMXGPTState),
+ VMSTATE_UINT32(next_timeout, IMXGPTState),
+ VMSTATE_UINT32(next_int, IMXGPTState),
+ VMSTATE_UINT32(freq, IMXGPTState),
+ VMSTATE_PTIMER(timer, IMXGPTState),
+ VMSTATE_END_OF_LIST()
+ }
+};
+
+static const IMXClk imx_gpt_clocks[] = {
+ NOCLK, /* 000 No clock source */
+ IPG, /* 001 ipg_clk, 532MHz*/
+ IPG, /* 010 ipg_clk_highfreq */
+ NOCLK, /* 011 not defined */
+ CLK_32k, /* 100 ipg_clk_32k */
+ NOCLK, /* 101 not defined */
+ NOCLK, /* 110 not defined */
+ NOCLK, /* 111 not defined */
+};
+
+static void imx_gpt_set_freq(IMXGPTState *s)
+{
+ uint32_t clksrc = extract32(s->cr, GPT_CR_CLKSRC_SHIFT, 3);
+ uint32_t freq = imx_clock_frequency(s->ccm, imx_gpt_clocks[clksrc])
+ / (1 + s->pr);
+ s->freq = freq;
+
+ DPRINTF("Setting clksrc %d to frequency %d\n", clksrc, freq);
+
+ if (freq) {
+ ptimer_set_freq(s->timer, freq);
+ }
+}
+
+static void imx_gpt_update_int(IMXGPTState *s)
+{
+ if ((s->sr & s->ir) && (s->cr & GPT_CR_EN)) {
+ qemu_irq_raise(s->irq);
+ } else {
+ qemu_irq_lower(s->irq);
+ }
+}
+
+static uint32_t imx_gpt_update_count(IMXGPTState *s)
+{
+ s->cnt = s->next_timeout - (uint32_t)ptimer_get_count(s->timer);
+
+ return s->cnt;
+}
+
+static inline uint32_t imx_gpt_find_limit(uint32_t count, uint32_t reg,
+ uint32_t timeout)
+{
+ if ((count < reg) && (timeout > reg)) {
+ timeout = reg;
+ }
+
+ return timeout;
+}
+
+static void imx_gpt_compute_next_timeout(IMXGPTState *s, bool event)
+{
+ uint32_t timeout = GPT_TIMER_MAX;
+ uint32_t count = 0;
+ long long limit;
+
+ if (!(s->cr & GPT_CR_EN)) {
+ /* if not enabled just return */
+ return;
+ }
+
+ if (event) {
+ /* This is a timer event */
+
+ if ((s->cr & GPT_CR_FRR) && (s->next_timeout != GPT_TIMER_MAX)) {
+ /*
+ * if we are in free running mode and we have not reached
+ * the GPT_TIMER_MAX limit, then update the count
+ */
+ count = imx_gpt_update_count(s);
+ }
+ } else {
+ /* not a timer event, then just update the count */
+
+ count = imx_gpt_update_count(s);
+ }
+
+ /* now, find the next timeout related to count */
+
+ if (s->ir & GPT_IR_OF1IE) {
+ timeout = imx_gpt_find_limit(count, s->ocr1, timeout);
+ }
+ if (s->ir & GPT_IR_OF2IE) {
+ timeout = imx_gpt_find_limit(count, s->ocr2, timeout);
+ }
+ if (s->ir & GPT_IR_OF3IE) {
+ timeout = imx_gpt_find_limit(count, s->ocr3, timeout);
+ }
+
+ /* find the next set of interrupts to raise for next timer event */
+
+ s->next_int = 0;
+ if ((s->ir & GPT_IR_OF1IE) && (timeout == s->ocr1)) {
+ s->next_int |= GPT_SR_OF1;
+ }
+ if ((s->ir & GPT_IR_OF2IE) && (timeout == s->ocr2)) {
+ s->next_int |= GPT_SR_OF2;
+ }
+ if ((s->ir & GPT_IR_OF3IE) && (timeout == s->ocr3)) {
+ s->next_int |= GPT_SR_OF3;
+ }
+ if ((s->ir & GPT_IR_ROVIE) && (timeout == GPT_TIMER_MAX)) {
+ s->next_int |= GPT_SR_ROV;
+ }
+
+ /* the new range to count down from */
+ limit = timeout - imx_gpt_update_count(s);
+
+ if (limit < 0) {
+ /*
+ * if we reach here, then QEMU is running too slow and we pass the
+ * timeout limit while computing it. Let's deliver the interrupt
+ * and compute a new limit.
+ */
+ s->sr |= s->next_int;
+
+ imx_gpt_compute_next_timeout(s, event);
+
+ imx_gpt_update_int(s);
+ } else {
+ /* New timeout value */
+ s->next_timeout = timeout;
+
+ /* reset the limit to the computed range */
+ ptimer_set_limit(s->timer, limit, 1);
+ }
+}
+
+static uint64_t imx_gpt_read(void *opaque, hwaddr offset, unsigned size)
+{
+ IMXGPTState *s = IMX_GPT(opaque);
+ uint32_t reg_value = 0;
+ uint32_t reg = offset >> 2;
+
+ switch (reg) {
+ case 0: /* Control Register */
+ reg_value = s->cr;
+ break;
+
+ case 1: /* prescaler */
+ reg_value = s->pr;
+ break;
+
+ case 2: /* Status Register */
+ reg_value = s->sr;
+ break;
+
+ case 3: /* Interrupt Register */
+ reg_value = s->ir;
+ break;
+
+ case 4: /* Output Compare Register 1 */
+ reg_value = s->ocr1;
+ break;
+
+ case 5: /* Output Compare Register 2 */
+ reg_value = s->ocr2;
+ break;
+
+ case 6: /* Output Compare Register 3 */
+ reg_value = s->ocr3;
+ break;
+
+ case 7: /* input Capture Register 1 */
+ qemu_log_mask(LOG_UNIMP, "icr1 feature is not implemented\n");
+ reg_value = s->icr1;
+ break;
+
+ case 8: /* input Capture Register 2 */
+ qemu_log_mask(LOG_UNIMP, "icr2 feature is not implemented\n");
+ reg_value = s->icr2;
+ break;
+
+ case 9: /* cnt */
+ imx_gpt_update_count(s);
+ reg_value = s->cnt;
+ break;
+
+ default:
+ IPRINTF("Bad offset %x\n", reg);
+ break;
+ }
+
+ DPRINTF("(%s) = 0x%08x\n", imx_gpt_reg_name(reg), reg_value);
+
+ return reg_value;
+}
+
+static void imx_gpt_reset(DeviceState *dev)
+{
+ IMXGPTState *s = IMX_GPT(dev);
+
+ /* stop timer */
+ ptimer_stop(s->timer);
+
+ /*
+ * Soft reset doesn't touch some bits; hard reset clears them
+ */
+ s->cr &= ~(GPT_CR_EN|GPT_CR_ENMOD|GPT_CR_STOPEN|GPT_CR_DOZEN|
+ GPT_CR_WAITEN|GPT_CR_DBGEN);
+ s->sr = 0;
+ s->pr = 0;
+ s->ir = 0;
+ s->cnt = 0;
+ s->ocr1 = GPT_TIMER_MAX;
+ s->ocr2 = GPT_TIMER_MAX;
+ s->ocr3 = GPT_TIMER_MAX;
+ s->icr1 = 0;
+ s->icr2 = 0;
+
+ s->next_timeout = GPT_TIMER_MAX;
+ s->next_int = 0;
+
+ /* compute new freq */
+ imx_gpt_set_freq(s);
+
+ /* reset the limit to GPT_TIMER_MAX */
+ ptimer_set_limit(s->timer, GPT_TIMER_MAX, 1);
+
+ /* if the timer is still enabled, restart it */
+ if (s->freq && (s->cr & GPT_CR_EN)) {
+ ptimer_run(s->timer, 1);
+ }
+}
+
+static void imx_gpt_write(void *opaque, hwaddr offset, uint64_t value,
+ unsigned size)
+{
+ IMXGPTState *s = IMX_GPT(opaque);
+ uint32_t oldreg;
+ uint32_t reg = offset >> 2;
+
+ DPRINTF("(%s, value = 0x%08x)\n", imx_gpt_reg_name(reg),
+ (uint32_t)value);
+
+ switch (reg) {
+ case 0:
+ oldreg = s->cr;
+ s->cr = value & ~0x7c14;
+ if (s->cr & GPT_CR_SWR) { /* force reset */
+ /* handle the reset */
+ imx_gpt_reset(DEVICE(s));
+ } else {
+ /* set our freq, as the source might have changed */
+ imx_gpt_set_freq(s);
+
+ if ((oldreg ^ s->cr) & GPT_CR_EN) {
+ if (s->cr & GPT_CR_EN) {
+ if (s->cr & GPT_CR_ENMOD) {
+ s->next_timeout = GPT_TIMER_MAX;
+ ptimer_set_count(s->timer, GPT_TIMER_MAX);
+ imx_gpt_compute_next_timeout(s, false);
+ }
+ ptimer_run(s->timer, 1);
+ } else {
+ /* stop timer */
+ ptimer_stop(s->timer);
+ }
+ }
+ }
+ break;
+
+ case 1: /* Prescaler */
+ s->pr = value & 0xfff;
+ imx_gpt_set_freq(s);
+ break;
+
+ case 2: /* SR */
+ s->sr &= ~(value & 0x3f);
+ imx_gpt_update_int(s);
+ break;
+
+ case 3: /* IR -- interrupt register */
+ s->ir = value & 0x3f;
+ imx_gpt_update_int(s);
+
+ imx_gpt_compute_next_timeout(s, false);
+
+ break;
+
+ case 4: /* OCR1 -- output compare register */
+ s->ocr1 = value;
+
+ /* In non-freerun mode, reset count when this register is written */
+ if (!(s->cr & GPT_CR_FRR)) {
+ s->next_timeout = GPT_TIMER_MAX;
+ ptimer_set_limit(s->timer, GPT_TIMER_MAX, 1);
+ }
+
+ /* compute the new timeout */
+ imx_gpt_compute_next_timeout(s, false);
+
+ break;
+
+ case 5: /* OCR2 -- output compare register */
+ s->ocr2 = value;
+
+ /* compute the new timeout */
+ imx_gpt_compute_next_timeout(s, false);
+
+ break;
+
+ case 6: /* OCR3 -- output compare register */
+ s->ocr3 = value;
+
+ /* compute the new timeout */
+ imx_gpt_compute_next_timeout(s, false);
+
+ break;
+
+ default:
+ IPRINTF("Bad offset %x\n", reg);
+ break;
+ }
+}
+
+static void imx_gpt_timeout(void *opaque)
+{
+ IMXGPTState *s = IMX_GPT(opaque);
+
+ DPRINTF("\n");
+
+ s->sr |= s->next_int;
+ s->next_int = 0;
+
+ imx_gpt_compute_next_timeout(s, true);
+
+ imx_gpt_update_int(s);
+
+ if (s->freq && (s->cr & GPT_CR_EN)) {
+ ptimer_run(s->timer, 1);
+ }
+}
+
+static const MemoryRegionOps imx_gpt_ops = {
+ .read = imx_gpt_read,
+ .write = imx_gpt_write,
+ .endianness = DEVICE_NATIVE_ENDIAN,
+};
+
+
+static void imx_gpt_realize(DeviceState *dev, Error **errp)
+{
+ IMXGPTState *s = IMX_GPT(dev);
+ SysBusDevice *sbd = SYS_BUS_DEVICE(dev);
+ QEMUBH *bh;
+
+ sysbus_init_irq(sbd, &s->irq);
+ memory_region_init_io(&s->iomem, OBJECT(s), &imx_gpt_ops, s, TYPE_IMX_GPT,
+ 0x00001000);
+ sysbus_init_mmio(sbd, &s->iomem);
+
+ bh = qemu_bh_new(imx_gpt_timeout, s);
+ s->timer = ptimer_init(bh);
+}
+
+void imx_timerg_create(const hwaddr addr, qemu_irq irq, DeviceState *ccm)
+{
+ IMXGPTState *pp;
+ DeviceState *dev;
+
+ dev = sysbus_create_simple(TYPE_IMX_GPT, addr, irq);
+ pp = IMX_GPT(dev);
+ pp->ccm = ccm;
+}
+
+static void imx_gpt_class_init(ObjectClass *klass, void *data)
+{
+ DeviceClass *dc = DEVICE_CLASS(klass);
+
+ dc->realize = imx_gpt_realize;
+ dc->reset = imx_gpt_reset;
+ dc->vmsd = &vmstate_imx_timer_gpt;
+ dc->desc = "i.MX general timer";
+}
+
+static const TypeInfo imx_gpt_info = {
+ .name = TYPE_IMX_GPT,
+ .parent = TYPE_SYS_BUS_DEVICE,
+ .instance_size = sizeof(IMXGPTState),
+ .class_init = imx_gpt_class_init,
+};
+
+static void imx_gpt_register_types(void)
+{
+ type_register_static(&imx_gpt_info);
+}
+
+type_init(imx_gpt_register_types)