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-rw-r--r--src/hw/i2c/omap_i2c.c504
1 files changed, 504 insertions, 0 deletions
diff --git a/src/hw/i2c/omap_i2c.c b/src/hw/i2c/omap_i2c.c
new file mode 100644
index 0000000..b6f544a
--- /dev/null
+++ b/src/hw/i2c/omap_i2c.c
@@ -0,0 +1,504 @@
+/*
+ * TI OMAP on-chip I2C controller. Only "new I2C" mode supported.
+ *
+ * Copyright (C) 2007 Andrzej Zaborowski <balrog@zabor.org>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of
+ * the License, or (at your option) any later version.
+ *
+ * This program 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 General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, see <http://www.gnu.org/licenses/>.
+ */
+#include "hw/hw.h"
+#include "hw/i2c/i2c.h"
+#include "hw/arm/omap.h"
+#include "hw/sysbus.h"
+
+#define TYPE_OMAP_I2C "omap_i2c"
+#define OMAP_I2C(obj) OBJECT_CHECK(OMAPI2CState, (obj), TYPE_OMAP_I2C)
+
+typedef struct OMAPI2CState {
+ SysBusDevice parent_obj;
+
+ MemoryRegion iomem;
+ qemu_irq irq;
+ qemu_irq drq[2];
+ I2CBus *bus;
+
+ uint8_t revision;
+ void *iclk;
+ void *fclk;
+
+ uint8_t mask;
+ uint16_t stat;
+ uint16_t dma;
+ uint16_t count;
+ int count_cur;
+ uint32_t fifo;
+ int rxlen;
+ int txlen;
+ uint16_t control;
+ uint16_t addr[2];
+ uint8_t divider;
+ uint8_t times[2];
+ uint16_t test;
+} OMAPI2CState;
+
+#define OMAP2_INTR_REV 0x34
+#define OMAP2_GC_REV 0x34
+
+static void omap_i2c_interrupts_update(OMAPI2CState *s)
+{
+ qemu_set_irq(s->irq, s->stat & s->mask);
+ if ((s->dma >> 15) & 1) /* RDMA_EN */
+ qemu_set_irq(s->drq[0], (s->stat >> 3) & 1); /* RRDY */
+ if ((s->dma >> 7) & 1) /* XDMA_EN */
+ qemu_set_irq(s->drq[1], (s->stat >> 4) & 1); /* XRDY */
+}
+
+static void omap_i2c_fifo_run(OMAPI2CState *s)
+{
+ int ack = 1;
+
+ if (!i2c_bus_busy(s->bus))
+ return;
+
+ if ((s->control >> 2) & 1) { /* RM */
+ if ((s->control >> 1) & 1) { /* STP */
+ i2c_end_transfer(s->bus);
+ s->control &= ~(1 << 1); /* STP */
+ s->count_cur = s->count;
+ s->txlen = 0;
+ } else if ((s->control >> 9) & 1) { /* TRX */
+ while (ack && s->txlen)
+ ack = (i2c_send(s->bus,
+ (s->fifo >> ((-- s->txlen) << 3)) &
+ 0xff) >= 0);
+ s->stat |= 1 << 4; /* XRDY */
+ } else {
+ while (s->rxlen < 4)
+ s->fifo |= i2c_recv(s->bus) << ((s->rxlen ++) << 3);
+ s->stat |= 1 << 3; /* RRDY */
+ }
+ } else {
+ if ((s->control >> 9) & 1) { /* TRX */
+ while (ack && s->count_cur && s->txlen) {
+ ack = (i2c_send(s->bus,
+ (s->fifo >> ((-- s->txlen) << 3)) &
+ 0xff) >= 0);
+ s->count_cur --;
+ }
+ if (ack && s->count_cur)
+ s->stat |= 1 << 4; /* XRDY */
+ else
+ s->stat &= ~(1 << 4); /* XRDY */
+ if (!s->count_cur) {
+ s->stat |= 1 << 2; /* ARDY */
+ s->control &= ~(1 << 10); /* MST */
+ }
+ } else {
+ while (s->count_cur && s->rxlen < 4) {
+ s->fifo |= i2c_recv(s->bus) << ((s->rxlen ++) << 3);
+ s->count_cur --;
+ }
+ if (s->rxlen)
+ s->stat |= 1 << 3; /* RRDY */
+ else
+ s->stat &= ~(1 << 3); /* RRDY */
+ }
+ if (!s->count_cur) {
+ if ((s->control >> 1) & 1) { /* STP */
+ i2c_end_transfer(s->bus);
+ s->control &= ~(1 << 1); /* STP */
+ s->count_cur = s->count;
+ s->txlen = 0;
+ } else {
+ s->stat |= 1 << 2; /* ARDY */
+ s->control &= ~(1 << 10); /* MST */
+ }
+ }
+ }
+
+ s->stat |= (!ack) << 1; /* NACK */
+ if (!ack)
+ s->control &= ~(1 << 1); /* STP */
+}
+
+static void omap_i2c_reset(DeviceState *dev)
+{
+ OMAPI2CState *s = OMAP_I2C(dev);
+
+ s->mask = 0;
+ s->stat = 0;
+ s->dma = 0;
+ s->count = 0;
+ s->count_cur = 0;
+ s->fifo = 0;
+ s->rxlen = 0;
+ s->txlen = 0;
+ s->control = 0;
+ s->addr[0] = 0;
+ s->addr[1] = 0;
+ s->divider = 0;
+ s->times[0] = 0;
+ s->times[1] = 0;
+ s->test = 0;
+}
+
+static uint32_t omap_i2c_read(void *opaque, hwaddr addr)
+{
+ OMAPI2CState *s = opaque;
+ int offset = addr & OMAP_MPUI_REG_MASK;
+ uint16_t ret;
+
+ switch (offset) {
+ case 0x00: /* I2C_REV */
+ return s->revision; /* REV */
+
+ case 0x04: /* I2C_IE */
+ return s->mask;
+
+ case 0x08: /* I2C_STAT */
+ return s->stat | (i2c_bus_busy(s->bus) << 12);
+
+ case 0x0c: /* I2C_IV */
+ if (s->revision >= OMAP2_INTR_REV)
+ break;
+ ret = ctz32(s->stat & s->mask);
+ if (ret != 32) {
+ s->stat ^= 1 << ret;
+ ret++;
+ } else {
+ ret = 0;
+ }
+ omap_i2c_interrupts_update(s);
+ return ret;
+
+ case 0x10: /* I2C_SYSS */
+ return (s->control >> 15) & 1; /* I2C_EN */
+
+ case 0x14: /* I2C_BUF */
+ return s->dma;
+
+ case 0x18: /* I2C_CNT */
+ return s->count_cur; /* DCOUNT */
+
+ case 0x1c: /* I2C_DATA */
+ ret = 0;
+ if (s->control & (1 << 14)) { /* BE */
+ ret |= ((s->fifo >> 0) & 0xff) << 8;
+ ret |= ((s->fifo >> 8) & 0xff) << 0;
+ } else {
+ ret |= ((s->fifo >> 8) & 0xff) << 8;
+ ret |= ((s->fifo >> 0) & 0xff) << 0;
+ }
+ if (s->rxlen == 1) {
+ s->stat |= 1 << 15; /* SBD */
+ s->rxlen = 0;
+ } else if (s->rxlen > 1) {
+ if (s->rxlen > 2)
+ s->fifo >>= 16;
+ s->rxlen -= 2;
+ } else {
+ /* XXX: remote access (qualifier) error - what's that? */
+ }
+ if (!s->rxlen) {
+ s->stat &= ~(1 << 3); /* RRDY */
+ if (((s->control >> 10) & 1) && /* MST */
+ ((~s->control >> 9) & 1)) { /* TRX */
+ s->stat |= 1 << 2; /* ARDY */
+ s->control &= ~(1 << 10); /* MST */
+ }
+ }
+ s->stat &= ~(1 << 11); /* ROVR */
+ omap_i2c_fifo_run(s);
+ omap_i2c_interrupts_update(s);
+ return ret;
+
+ case 0x20: /* I2C_SYSC */
+ return 0;
+
+ case 0x24: /* I2C_CON */
+ return s->control;
+
+ case 0x28: /* I2C_OA */
+ return s->addr[0];
+
+ case 0x2c: /* I2C_SA */
+ return s->addr[1];
+
+ case 0x30: /* I2C_PSC */
+ return s->divider;
+
+ case 0x34: /* I2C_SCLL */
+ return s->times[0];
+
+ case 0x38: /* I2C_SCLH */
+ return s->times[1];
+
+ case 0x3c: /* I2C_SYSTEST */
+ if (s->test & (1 << 15)) { /* ST_EN */
+ s->test ^= 0xa;
+ return s->test;
+ } else
+ return s->test & ~0x300f;
+ }
+
+ OMAP_BAD_REG(addr);
+ return 0;
+}
+
+static void omap_i2c_write(void *opaque, hwaddr addr,
+ uint32_t value)
+{
+ OMAPI2CState *s = opaque;
+ int offset = addr & OMAP_MPUI_REG_MASK;
+ int nack;
+
+ switch (offset) {
+ case 0x00: /* I2C_REV */
+ case 0x0c: /* I2C_IV */
+ case 0x10: /* I2C_SYSS */
+ OMAP_RO_REG(addr);
+ return;
+
+ case 0x04: /* I2C_IE */
+ s->mask = value & (s->revision < OMAP2_GC_REV ? 0x1f : 0x3f);
+ break;
+
+ case 0x08: /* I2C_STAT */
+ if (s->revision < OMAP2_INTR_REV) {
+ OMAP_RO_REG(addr);
+ return;
+ }
+
+ /* RRDY and XRDY are reset by hardware. (in all versions???) */
+ s->stat &= ~(value & 0x27);
+ omap_i2c_interrupts_update(s);
+ break;
+
+ case 0x14: /* I2C_BUF */
+ s->dma = value & 0x8080;
+ if (value & (1 << 15)) /* RDMA_EN */
+ s->mask &= ~(1 << 3); /* RRDY_IE */
+ if (value & (1 << 7)) /* XDMA_EN */
+ s->mask &= ~(1 << 4); /* XRDY_IE */
+ break;
+
+ case 0x18: /* I2C_CNT */
+ s->count = value; /* DCOUNT */
+ break;
+
+ case 0x1c: /* I2C_DATA */
+ if (s->txlen > 2) {
+ /* XXX: remote access (qualifier) error - what's that? */
+ break;
+ }
+ s->fifo <<= 16;
+ s->txlen += 2;
+ if (s->control & (1 << 14)) { /* BE */
+ s->fifo |= ((value >> 8) & 0xff) << 8;
+ s->fifo |= ((value >> 0) & 0xff) << 0;
+ } else {
+ s->fifo |= ((value >> 0) & 0xff) << 8;
+ s->fifo |= ((value >> 8) & 0xff) << 0;
+ }
+ s->stat &= ~(1 << 10); /* XUDF */
+ if (s->txlen > 2)
+ s->stat &= ~(1 << 4); /* XRDY */
+ omap_i2c_fifo_run(s);
+ omap_i2c_interrupts_update(s);
+ break;
+
+ case 0x20: /* I2C_SYSC */
+ if (s->revision < OMAP2_INTR_REV) {
+ OMAP_BAD_REG(addr);
+ return;
+ }
+
+ if (value & 2) {
+ omap_i2c_reset(DEVICE(s));
+ }
+ break;
+
+ case 0x24: /* I2C_CON */
+ s->control = value & 0xcf87;
+ if (~value & (1 << 15)) { /* I2C_EN */
+ if (s->revision < OMAP2_INTR_REV) {
+ omap_i2c_reset(DEVICE(s));
+ }
+ break;
+ }
+ if ((value & (1 << 15)) && !(value & (1 << 10))) { /* MST */
+ fprintf(stderr, "%s: I^2C slave mode not supported\n",
+ __FUNCTION__);
+ break;
+ }
+ if ((value & (1 << 15)) && value & (1 << 8)) { /* XA */
+ fprintf(stderr, "%s: 10-bit addressing mode not supported\n",
+ __FUNCTION__);
+ break;
+ }
+ if ((value & (1 << 15)) && value & (1 << 0)) { /* STT */
+ nack = !!i2c_start_transfer(s->bus, s->addr[1], /* SA */
+ (~value >> 9) & 1); /* TRX */
+ s->stat |= nack << 1; /* NACK */
+ s->control &= ~(1 << 0); /* STT */
+ s->fifo = 0;
+ if (nack)
+ s->control &= ~(1 << 1); /* STP */
+ else {
+ s->count_cur = s->count;
+ omap_i2c_fifo_run(s);
+ }
+ omap_i2c_interrupts_update(s);
+ }
+ break;
+
+ case 0x28: /* I2C_OA */
+ s->addr[0] = value & 0x3ff;
+ break;
+
+ case 0x2c: /* I2C_SA */
+ s->addr[1] = value & 0x3ff;
+ break;
+
+ case 0x30: /* I2C_PSC */
+ s->divider = value;
+ break;
+
+ case 0x34: /* I2C_SCLL */
+ s->times[0] = value;
+ break;
+
+ case 0x38: /* I2C_SCLH */
+ s->times[1] = value;
+ break;
+
+ case 0x3c: /* I2C_SYSTEST */
+ s->test = value & 0xf80f;
+ if (value & (1 << 11)) /* SBB */
+ if (s->revision >= OMAP2_INTR_REV) {
+ s->stat |= 0x3f;
+ omap_i2c_interrupts_update(s);
+ }
+ if (value & (1 << 15)) /* ST_EN */
+ fprintf(stderr, "%s: System Test not supported\n", __FUNCTION__);
+ break;
+
+ default:
+ OMAP_BAD_REG(addr);
+ return;
+ }
+}
+
+static void omap_i2c_writeb(void *opaque, hwaddr addr,
+ uint32_t value)
+{
+ OMAPI2CState *s = opaque;
+ int offset = addr & OMAP_MPUI_REG_MASK;
+
+ switch (offset) {
+ case 0x1c: /* I2C_DATA */
+ if (s->txlen > 2) {
+ /* XXX: remote access (qualifier) error - what's that? */
+ break;
+ }
+ s->fifo <<= 8;
+ s->txlen += 1;
+ s->fifo |= value & 0xff;
+ s->stat &= ~(1 << 10); /* XUDF */
+ if (s->txlen > 2)
+ s->stat &= ~(1 << 4); /* XRDY */
+ omap_i2c_fifo_run(s);
+ omap_i2c_interrupts_update(s);
+ break;
+
+ default:
+ OMAP_BAD_REG(addr);
+ return;
+ }
+}
+
+static const MemoryRegionOps omap_i2c_ops = {
+ .old_mmio = {
+ .read = {
+ omap_badwidth_read16,
+ omap_i2c_read,
+ omap_badwidth_read16,
+ },
+ .write = {
+ omap_i2c_writeb, /* Only the last fifo write can be 8 bit. */
+ omap_i2c_write,
+ omap_badwidth_write16,
+ },
+ },
+ .endianness = DEVICE_NATIVE_ENDIAN,
+};
+
+static int omap_i2c_init(SysBusDevice *sbd)
+{
+ DeviceState *dev = DEVICE(sbd);
+ OMAPI2CState *s = OMAP_I2C(dev);
+
+ if (!s->fclk) {
+ hw_error("omap_i2c: fclk not connected\n");
+ }
+ if (s->revision >= OMAP2_INTR_REV && !s->iclk) {
+ /* Note that OMAP1 doesn't have a separate interface clock */
+ hw_error("omap_i2c: iclk not connected\n");
+ }
+ sysbus_init_irq(sbd, &s->irq);
+ sysbus_init_irq(sbd, &s->drq[0]);
+ sysbus_init_irq(sbd, &s->drq[1]);
+ memory_region_init_io(&s->iomem, OBJECT(s), &omap_i2c_ops, s, "omap.i2c",
+ (s->revision < OMAP2_INTR_REV) ? 0x800 : 0x1000);
+ sysbus_init_mmio(sbd, &s->iomem);
+ s->bus = i2c_init_bus(dev, NULL);
+ return 0;
+}
+
+static Property omap_i2c_properties[] = {
+ DEFINE_PROP_UINT8("revision", OMAPI2CState, revision, 0),
+ DEFINE_PROP_PTR("iclk", OMAPI2CState, iclk),
+ DEFINE_PROP_PTR("fclk", OMAPI2CState, fclk),
+ DEFINE_PROP_END_OF_LIST(),
+};
+
+static void omap_i2c_class_init(ObjectClass *klass, void *data)
+{
+ DeviceClass *dc = DEVICE_CLASS(klass);
+ SysBusDeviceClass *k = SYS_BUS_DEVICE_CLASS(klass);
+ k->init = omap_i2c_init;
+ dc->props = omap_i2c_properties;
+ dc->reset = omap_i2c_reset;
+ /* Reason: pointer properties "iclk", "fclk" */
+ dc->cannot_instantiate_with_device_add_yet = true;
+}
+
+static const TypeInfo omap_i2c_info = {
+ .name = TYPE_OMAP_I2C,
+ .parent = TYPE_SYS_BUS_DEVICE,
+ .instance_size = sizeof(OMAPI2CState),
+ .class_init = omap_i2c_class_init,
+};
+
+static void omap_i2c_register_types(void)
+{
+ type_register_static(&omap_i2c_info);
+}
+
+I2CBus *omap_i2c_bus(DeviceState *omap_i2c)
+{
+ OMAPI2CState *s = OMAP_I2C(omap_i2c);
+ return s->bus;
+}
+
+type_init(omap_i2c_register_types)
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