From 4a2c8ac2bc67d689bc7df130d3105af52fa36b18 Mon Sep 17 00:00:00 2001 From: balrog Date: Sat, 3 Nov 2007 00:51:03 +0000 Subject: [PATCH] Initial OMAP I^2C controller implementation (communication not tested). Correct an i2c_start_transfer comment. git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@3514 c046a42c-6fe2-441c-8c8c-71466251a162 --- hw/i2c.c | 3 +- hw/omap.c | 420 ++++++++++++++++++++++++++++++++++++++++++++++++++++++ hw/omap.h | 7 + 3 files changed, 428 insertions(+), 2 deletions(-) diff --git a/hw/i2c.c b/hw/i2c.c index f0d117c144..627bbfc4e1 100644 --- a/hw/i2c.c +++ b/hw/i2c.c @@ -51,8 +51,7 @@ int i2c_bus_busy(i2c_bus *bus) return bus->current_dev != NULL; } -/* Returns nonzero if the bus is already busy, or is the address is not - valid. */ +/* Returns non-zero if the address is not valid. */ /* TODO: Make this handle multiple masters. */ int i2c_start_transfer(i2c_bus *bus, int address, int recv) { diff --git a/hw/omap.c b/hw/omap.c index 67d9ea7fce..ef03868384 100644 --- a/hw/omap.c +++ b/hw/omap.c @@ -3603,6 +3603,421 @@ static void omap_pwt_init(target_phys_addr_t base, struct omap_mpu_state_s *s, cpu_register_physical_memory(s->pwt.base, 0x800, iomemtype); } +/* Inter-Integrated Circuit Controller (only the "New I2C") */ +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 */ +} + +static 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; +} + /* General chip reset */ static void omap_mpu_reset(void *opaque) { @@ -3634,6 +4049,8 @@ static void omap_mpu_reset(void *opaque) omap_gpio_reset(mpu->gpio); omap_uwire_reset(mpu->microwire); omap_pwl_reset(mpu); + omap_pwt_reset(mpu); + omap_i2c_reset(mpu->i2c); cpu_reset(mpu->env); } @@ -3758,6 +4175,9 @@ struct omap_mpu_state_s *omap310_mpu_init(unsigned long sdram_size, omap_pwl_init(0xfffb5800, s, omap_findclk(s, "clk32-kHz")); omap_pwt_init(0xfffb6000, s, omap_findclk(s, "xtal_osc_12m")); + s->i2c = omap_i2c_init(0xfffb3800, s->irq[1][OMAP_INT_I2C], + &s->drq[OMAP_DMA_I2C_RX], omap_findclk(s, "mpuper_ck")); + qemu_register_reset(omap_mpu_reset, s); return s; diff --git a/hw/omap.h b/hw/omap.h index 0735fcc7e0..4b5b579736 100644 --- a/hw/omap.h +++ b/hw/omap.h @@ -475,6 +475,11 @@ struct omap_uwire_s *omap_uwire_init(target_phys_addr_t base, void omap_uwire_attach(struct omap_uwire_s *s, struct uwire_slave_s *slave, int chipselect); +struct omap_i2c_s; +struct omap_i2c_s *omap_i2c_init(target_phys_addr_t base, + qemu_irq irq, qemu_irq *dma, omap_clk clk); +i2c_bus *omap_i2c_bus(struct omap_i2c_s *s); + /* omap_lcdc.c */ struct omap_lcd_panel_s; void omap_lcdc_reset(struct omap_lcd_panel_s *s); @@ -550,6 +555,8 @@ struct omap_mpu_state_s { omap_clk clk; } pwt; + struct omap_i2c_s *i2c; + /* MPU private TIPB peripherals */ struct omap_intr_handler_s *ih[2];