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-rw-r--r--hw/omap_i2c.c435
1 files changed, 435 insertions, 0 deletions
diff --git a/hw/omap_i2c.c b/hw/omap_i2c.c
new file mode 100644
index 0000000000..af00be3207
--- /dev/null
+++ b/hw/omap_i2c.c
@@ -0,0 +1,435 @@
+/*
+ * 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, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
+ * MA 02111-1307 USA
+ */
+#include "vl.h"
+
+struct omap_i2c_s {
+ target_phys_addr_t base;
+ qemu_irq irq;
+ qemu_irq drq[2];
+ i2c_slave slave;
+ i2c_bus *bus;
+
+ 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;
+};
+
+static void omap_i2c_interrupts_update(struct omap_i2c_s *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 */
+}
+
+/* These are only stubs now. */
+static void omap_i2c_event(i2c_slave *i2c, enum i2c_event event)
+{
+ struct omap_i2c_s *s = (struct omap_i2c_s *) i2c;
+
+ if ((~s->control >> 15) & 1) /* I2C_EN */
+ return;
+
+ switch (event) {
+ case I2C_START_SEND:
+ case I2C_START_RECV:
+ s->stat |= 1 << 9; /* AAS */
+ break;
+ case I2C_FINISH:
+ s->stat |= 1 << 2; /* ARDY */
+ break;
+ case I2C_NACK:
+ s->stat |= 1 << 1; /* NACK */
+ break;
+ }
+
+ omap_i2c_interrupts_update(s);
+}
+
+static int omap_i2c_rx(i2c_slave *i2c)
+{
+ struct omap_i2c_s *s = (struct omap_i2c_s *) i2c;
+ uint8_t ret = 0;
+
+ if ((~s->control >> 15) & 1) /* I2C_EN */
+ return -1;
+
+ if (s->txlen)
+ ret = s->fifo >> ((-- s->txlen) << 3) & 0xff;
+ else
+ s->stat |= 1 << 10; /* XUDF */
+ s->stat |= 1 << 4; /* XRDY */
+
+ omap_i2c_interrupts_update(s);
+ return ret;
+}
+
+static int omap_i2c_tx(i2c_slave *i2c, uint8_t data)
+{
+ struct omap_i2c_s *s = (struct omap_i2c_s *) i2c;
+
+ if ((~s->control >> 15) & 1) /* I2C_EN */
+ return 1;
+
+ if (s->rxlen < 4)
+ s->fifo |= data << ((s->rxlen ++) << 3);
+ else
+ s->stat |= 1 << 11; /* ROVR */
+ s->stat |= 1 << 3; /* RRDY */
+
+ omap_i2c_interrupts_update(s);
+ return 1;
+}
+
+static void omap_i2c_fifo_run(struct omap_i2c_s *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;
+ } 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 */
+ 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 */
+ }
+ 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;
+ } else {
+ s->stat |= 1 << 2; /* ARDY */
+ s->control &= ~(1 << 10); /* MST */
+ }
+ }
+ }
+
+ s->stat |= (!ack) << 1; /* NACK */
+ if (!ack)
+ s->control &= ~(1 << 1); /* STP */
+}
+
+void omap_i2c_reset(struct omap_i2c_s *s)
+{
+ 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, target_phys_addr_t addr)
+{
+ struct omap_i2c_s *s = (struct omap_i2c_s *) opaque;
+ int offset = addr - s->base;
+ uint16_t ret;
+
+ switch (offset) {
+ case 0x00: /* I2C_REV */
+ /* TODO: set a value greater or equal to real hardware */
+ return 0x11; /* 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 */
+ ret = ffs(s->stat & s->mask);
+ if (ret)
+ s->stat ^= 1 << (ret - 1);
+ omap_i2c_interrupts_update(s);
+ return ret;
+
+ 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 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, target_phys_addr_t addr,
+ uint32_t value)
+{
+ struct omap_i2c_s *s = (struct omap_i2c_s *) opaque;
+ int offset = addr - s->base;
+ int nack;
+
+ switch (offset) {
+ case 0x00: /* I2C_REV */
+ case 0x08: /* I2C_STAT */
+ case 0x0c: /* I2C_IV */
+ OMAP_BAD_REG(addr);
+ return;
+
+ case 0x04: /* I2C_IE */
+ s->mask = value & 0x1f;
+ 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 0x24: /* I2C_CON */
+ s->control = value & 0xcf07;
+ if (~value & (1 << 15)) { /* I2C_EN */
+ omap_i2c_reset(s);
+ break;
+ }
+ if (~value & (1 << 10)) { /* MST */
+ printf("%s: I^2C slave mode not supported\n", __FUNCTION__);
+ break;
+ }
+ if (value & (1 << 9)) { /* XA */
+ printf("%s: 10-bit addressing mode not supported\n", __FUNCTION__);
+ break;
+ }
+ if (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 */
+ if (nack)
+ s->control &= ~(1 << 1); /* STP */
+ else
+ omap_i2c_fifo_run(s);
+ omap_i2c_interrupts_update(s);
+ }
+ break;
+
+ case 0x28: /* I2C_OA */
+ s->addr[0] = value & 0x3ff;
+ i2c_set_slave_address(&s->slave, value & 0x7f);
+ 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 & 0xf00f;
+ if (value & (1 << 15)) /* ST_EN */
+ printf("%s: System Test not supported\n", __FUNCTION__);
+ break;
+
+ default:
+ OMAP_BAD_REG(addr);
+ return;
+ }
+}
+
+static CPUReadMemoryFunc *omap_i2c_readfn[] = {
+ omap_badwidth_read16,
+ omap_i2c_read,
+ omap_badwidth_read16,
+};
+
+static CPUWriteMemoryFunc *omap_i2c_writefn[] = {
+ omap_badwidth_write16,
+ omap_i2c_write,
+ omap_i2c_write, /* TODO: Only the last fifo write can be 8 bit. */
+};
+
+struct omap_i2c_s *omap_i2c_init(target_phys_addr_t base,
+ qemu_irq irq, qemu_irq *dma, omap_clk clk)
+{
+ int iomemtype;
+ struct omap_i2c_s *s = (struct omap_i2c_s *)
+ qemu_mallocz(sizeof(struct omap_i2c_s));
+
+ s->base = base;
+ s->irq = irq;
+ s->drq[0] = dma[0];
+ s->drq[1] = dma[1];
+ s->slave.event = omap_i2c_event;
+ s->slave.recv = omap_i2c_rx;
+ s->slave.send = omap_i2c_tx;
+ s->bus = i2c_init_bus();
+ omap_i2c_reset(s);
+
+ iomemtype = cpu_register_io_memory(0, omap_i2c_readfn,
+ omap_i2c_writefn, s);
+ cpu_register_physical_memory(s->base, 0x800, iomemtype);
+
+ return s;
+}
+
+i2c_bus *omap_i2c_bus(struct omap_i2c_s *s)
+{
+ return s->bus;
+}
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