qemu/hw/omap_i2c.c
Alexander Graf 2507c12ab0 Add endianness as io mem parameter
As stated before, devices can be little, big or native endian. The
target endianness is not of their concern, so we need to push things
down a level.

This patch adds a parameter to cpu_register_io_memory that allows a
device to choose its endianness. For now, all devices simply choose
native endian, because that's the same behavior as before.

Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
2010-12-11 15:24:25 +00:00

471 lines
13 KiB
C

/*
* 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.h"
#include "i2c.h"
#include "omap.h"
struct omap_i2c_s {
qemu_irq irq;
qemu_irq drq[2];
i2c_bus *bus;
uint8_t revision;
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;
};
#define OMAP2_INTR_REV 0x34
#define OMAP2_GC_REV 0x34
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 */
}
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;
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 */
}
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 & 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, target_phys_addr_t addr,
uint32_t value)
{
struct omap_i2c_s *s = (struct omap_i2c_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);
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);
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, target_phys_addr_t addr,
uint32_t value)
{
struct omap_i2c_s *s = (struct omap_i2c_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 CPUReadMemoryFunc * const omap_i2c_readfn[] = {
omap_badwidth_read16,
omap_i2c_read,
omap_badwidth_read16,
};
static CPUWriteMemoryFunc * const omap_i2c_writefn[] = {
omap_i2c_writeb, /* Only the last fifo write can be 8 bit. */
omap_i2c_write,
omap_badwidth_write16,
};
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));
/* TODO: set a value greater or equal to real hardware */
s->revision = 0x11;
s->irq = irq;
s->drq[0] = dma[0];
s->drq[1] = dma[1];
s->bus = i2c_init_bus(NULL, "i2c");
omap_i2c_reset(s);
iomemtype = cpu_register_io_memory(omap_i2c_readfn,
omap_i2c_writefn, s, DEVICE_NATIVE_ENDIAN);
cpu_register_physical_memory(base, 0x800, iomemtype);
return s;
}
struct omap_i2c_s *omap2_i2c_init(struct omap_target_agent_s *ta,
qemu_irq irq, qemu_irq *dma, omap_clk fclk, omap_clk iclk)
{
int iomemtype;
struct omap_i2c_s *s = (struct omap_i2c_s *)
qemu_mallocz(sizeof(struct omap_i2c_s));
s->revision = 0x34;
s->irq = irq;
s->drq[0] = dma[0];
s->drq[1] = dma[1];
s->bus = i2c_init_bus(NULL, "i2c");
omap_i2c_reset(s);
iomemtype = l4_register_io_memory(omap_i2c_readfn,
omap_i2c_writefn, s);
omap_l4_attach(ta, 0, iomemtype);
return s;
}
i2c_bus *omap_i2c_bus(struct omap_i2c_s *s)
{
return s->bus;
}