diff options
Diffstat (limited to 'hw/i2c/omap_i2c.c')
-rw-r--r-- | hw/i2c/omap_i2c.c | 492 |
1 files changed, 492 insertions, 0 deletions
diff --git a/hw/i2c/omap_i2c.c b/hw/i2c/omap_i2c.c new file mode 100644 index 0000000000..efb2254aea --- /dev/null +++ b/hw/i2c/omap_i2c.c @@ -0,0 +1,492 @@ +/* + * 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" + + +typedef struct OMAPI2CState { + SysBusDevice busdev; + MemoryRegion iomem; + qemu_irq irq; + qemu_irq drq[2]; + i2c_bus *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 = FROM_SYSBUS(OMAPI2CState, + SYS_BUS_DEVICE(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 = ffs(s->stat & s->mask); + if (ret) + s->stat ^= 1 << (ret - 1); + 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(&s->busdev.qdev); + break; + + case 0x24: /* I2C_CON */ + s->control = value & 0xcf87; + if (~value & (1 << 15)) { /* I2C_EN */ + if (s->revision < OMAP2_INTR_REV) + omap_i2c_reset(&s->busdev.qdev); + 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 *dev) +{ + OMAPI2CState *s = FROM_SYSBUS(OMAPI2CState, 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(dev, &s->irq); + sysbus_init_irq(dev, &s->drq[0]); + sysbus_init_irq(dev, &s->drq[1]); + memory_region_init_io(&s->iomem, &omap_i2c_ops, s, "omap.i2c", + (s->revision < OMAP2_INTR_REV) ? 0x800 : 0x1000); + sysbus_init_mmio(dev, &s->iomem); + s->bus = i2c_init_bus(&dev->qdev, 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; +} + +static const TypeInfo omap_i2c_info = { + .name = "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); +} + +i2c_bus *omap_i2c_bus(DeviceState *omap_i2c) +{ + OMAPI2CState *s = FROM_SYSBUS(OMAPI2CState, SYS_BUS_DEVICE(omap_i2c)); + return s->bus; +} + +type_init(omap_i2c_register_types) |