freebsd-dev/sys/dev/beri/beri_ring.c
Ruslan Bukin b0da449e60 Add driver for BERI soft processor 'ring buffer' device.
Ring device provides a way for communicate to BERI
peripherals such as BERI debug unit and console.

Sponsored by:	DARPA, AFRL
2014-10-19 16:26:49 +00:00

530 lines
11 KiB
C

/*-
* Copyright (c) 2014 Ruslan Bukin <br@bsdpad.com>
* All rights reserved.
*
* This software was developed by SRI International and the University of
* Cambridge Computer Laboratory under DARPA/AFRL contract (FA8750-10-C-0237)
* ("CTSRD"), as part of the DARPA CRASH research programme.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
/*
* SRI-Cambridge BERI soft processor <-> ARM core ring buffer.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/bus.h>
#include <sys/kernel.h>
#include <sys/module.h>
#include <sys/malloc.h>
#include <sys/rman.h>
#include <sys/timeet.h>
#include <sys/timetc.h>
#include <sys/conf.h>
#include <sys/uio.h>
#include <sys/stat.h>
#include <sys/time.h>
#include <sys/event.h>
#include <sys/selinfo.h>
#include <dev/fdt/fdt_common.h>
#include <dev/ofw/openfirm.h>
#include <dev/ofw/ofw_bus.h>
#include <dev/ofw/ofw_bus_subr.h>
#include <machine/bus.h>
#include <machine/fdt.h>
#include <machine/cpu.h>
#include <machine/intr.h>
#define READ4(_sc, _reg) \
bus_read_4((_sc)->res[0], _reg)
#define WRITE4(_sc, _reg, _val) \
bus_write_4((_sc)->res[0], _reg, _val)
#define CDES_INT_EN (1 << 15)
#define CDES_CAUSE_MASK 0x3
#define CDES_CAUSE_SHIFT 13
#define DEVNAME_MAXLEN 256
typedef struct
{
uint16_t cdes;
uint16_t interrupt_level;
uint16_t in;
uint16_t out;
} control_reg_t;
struct beri_softc {
struct resource *res[3];
bus_space_tag_t bst;
bus_space_handle_t bsh;
struct cdev *cdev;
device_t dev;
void *read_ih;
void *write_ih;
struct selinfo beri_rsel;
struct mtx beri_mtx;
int opened;
char devname[DEVNAME_MAXLEN];
int control_read;
int control_write;
int data_read;
int data_write;
int data_size;
};
static struct resource_spec beri_spec[] = {
{ SYS_RES_MEMORY, 0, RF_ACTIVE },
{ SYS_RES_IRQ, 0, RF_ACTIVE },
{ SYS_RES_IRQ, 1, RF_ACTIVE },
{ -1, 0 }
};
static control_reg_t
get_control_reg(struct beri_softc *sc, int dir)
{
uint32_t offset;
uint16_t dst[4];
control_reg_t c;
uint16_t *cp;
int i;
cp = (uint16_t *)&c;
offset = dir ? sc->control_write : sc->control_read;
((uint32_t *)dst)[0] = READ4(sc, offset);
((uint32_t *)dst)[1] = READ4(sc, offset + 4);
for (i = 0; i < 4; i++)
cp[i] = dst[3 - i];
return (c);
}
static void
set_control_reg(struct beri_softc *sc, int dir, control_reg_t *c)
{
uint32_t offset;
uint16_t src[4];
uint16_t *cp;
int i;
cp = (uint16_t *)c;
for (i = 0; i < 4; i++)
src[3 - i] = cp[i];
offset = dir ? sc->control_write : sc->control_read;
WRITE4(sc, offset + 0, ((uint32_t *)src)[0]);
WRITE4(sc, offset + 4, ((uint32_t *)src)[1]);
}
static int
get_stock(struct beri_softc *sc, int dir, control_reg_t *c)
{
uint32_t fill;
fill = (c->in - c->out + sc->data_size) % sc->data_size;
if (dir)
return (sc->data_size - fill - 1);
else
return (fill);
}
static void
beri_intr_write(void *arg)
{
struct beri_softc *sc;
control_reg_t c;
sc = arg;
c = get_control_reg(sc, 1);
if (c.cdes & CDES_INT_EN) {
c.cdes &= ~(CDES_INT_EN);
set_control_reg(sc, 1, &c);
}
mtx_lock(&sc->beri_mtx);
selwakeuppri(&sc->beri_rsel, PZERO + 1);
KNOTE_LOCKED(&sc->beri_rsel.si_note, 0);
mtx_unlock(&sc->beri_mtx);
}
static void
beri_intr_read(void *arg)
{
struct beri_softc *sc;
control_reg_t c;
sc = arg;
c = get_control_reg(sc, 0);
if (c.cdes & CDES_INT_EN) {
c.cdes &= ~(CDES_INT_EN);
set_control_reg(sc, 0, &c);
}
mtx_lock(&sc->beri_mtx);
selwakeuppri(&sc->beri_rsel, PZERO + 1);
KNOTE_LOCKED(&sc->beri_rsel.si_note, 0);
mtx_unlock(&sc->beri_mtx);
}
static int
beri_open(struct cdev *dev, int flags __unused,
int fmt __unused, struct thread *td __unused)
{
struct beri_softc *sc;
control_reg_t c;
sc = dev->si_drv1;
if (sc->opened)
return (1);
/* Setup interrupt handlers */
if (bus_setup_intr(sc->dev, sc->res[1], INTR_TYPE_BIO | INTR_MPSAFE,
NULL, beri_intr_read, sc, &sc->read_ih)) {
device_printf(sc->dev, "Unable to setup read intr\n");
return (1);
}
if (bus_setup_intr(sc->dev, sc->res[2], INTR_TYPE_BIO | INTR_MPSAFE,
NULL, beri_intr_write, sc, &sc->write_ih)) {
device_printf(sc->dev, "Unable to setup write intr\n");
return (1);
}
sc->opened = 1;
/* Clear write buffer */
c = get_control_reg(sc, 1);
c.in = c.out;
c.cdes = 0;
set_control_reg(sc, 1, &c);
/* Clear read buffer */
c = get_control_reg(sc, 0);
c.out = c.in;
c.cdes = 0;
set_control_reg(sc, 0, &c);
return (0);
}
static int
beri_close(struct cdev *dev, int flags __unused,
int fmt __unused, struct thread *td __unused)
{
struct beri_softc *sc;
sc = dev->si_drv1;
if (sc->opened) {
sc->opened = 0;
/* Unsetup interrupt handlers */
bus_teardown_intr(sc->dev, sc->res[1], sc->read_ih);
bus_teardown_intr(sc->dev, sc->res[2], sc->write_ih);
}
return (0);
}
static int
beri_rdwr(struct cdev *dev, struct uio *uio, int ioflag)
{
struct beri_softc *sc;
uint32_t offset;
control_reg_t c;
uint16_t *ptr;
uint8_t *dst;
int stock;
int dir;
int amount;
int count;
sc = dev->si_drv1;
dir = uio->uio_rw ? 1 : 0;
c = get_control_reg(sc, dir);
stock = get_stock(sc, dir, &c);
if (stock < uio->uio_resid) {
device_printf(sc->dev, "Err: no data/space available\n");
return (1);
}
amount = uio->uio_resid;
ptr = dir ? &c.in : &c.out;
count = (sc->data_size - *ptr);
offset = dir ? sc->data_write : sc->data_read;
dst = (uint8_t *)(sc->bsh + offset);
if (amount <= count) {
uiomove(dst + *ptr, amount, uio);
} else {
uiomove(dst + *ptr, count, uio);
uiomove(dst, (amount - count), uio);
}
*ptr = (*ptr + amount) % sc->data_size;
set_control_reg(sc, dir, &c);
return (0);
}
static int
beri_kqread(struct knote *kn, long hint)
{
struct beri_softc *sc;
control_reg_t c;
int stock;
sc = kn->kn_hook;
c = get_control_reg(sc, 0);
stock = get_stock(sc, 0, &c);
if (stock) {
kn->kn_data = stock;
return (1);
}
kn->kn_data = 0;
/* Wait at least one new byte in buffer */
c.interrupt_level = 1;
/* Enable interrupts */
c.cdes |= (CDES_INT_EN);
set_control_reg(sc, 0, &c);
return (0);
}
static int
beri_kqwrite(struct knote *kn, long hint)
{
struct beri_softc *sc;
control_reg_t c;
int stock;
sc = kn->kn_hook;
c = get_control_reg(sc, 1);
stock = get_stock(sc, 1, &c);
if (stock) {
kn->kn_data = stock;
return (1);
}
kn->kn_data = 0;
/* Wait at least one free position in buffer */
c.interrupt_level = sc->data_size - 2;
/* Enable interrupts */
c.cdes |= (CDES_INT_EN);
set_control_reg(sc, 1, &c);
return (0);
}
static void
beri_kqdetach(struct knote *kn)
{
struct beri_softc *sc;
sc = kn->kn_hook;
knlist_remove(&sc->beri_rsel.si_note, kn, 0);
}
static struct filterops beri_read_filterops = {
.f_isfd = 1,
.f_attach = NULL,
.f_detach = beri_kqdetach,
.f_event = beri_kqread,
};
static struct filterops beri_write_filterops = {
.f_isfd = 1,
.f_attach = NULL,
.f_detach = beri_kqdetach,
.f_event = beri_kqwrite,
};
static int
beri_kqfilter(struct cdev *dev, struct knote *kn)
{
struct beri_softc *sc;
sc = dev->si_drv1;
switch(kn->kn_filter) {
case EVFILT_READ:
kn->kn_fop = &beri_read_filterops;
break;
case EVFILT_WRITE:
kn->kn_fop = &beri_write_filterops;
break;
default:
return(EINVAL);
}
kn->kn_hook = sc;
knlist_add(&sc->beri_rsel.si_note, kn, 0);
return (0);
}
static struct cdevsw beri_cdevsw = {
.d_version = D_VERSION,
.d_open = beri_open,
.d_close = beri_close,
.d_write = beri_rdwr,
.d_read = beri_rdwr,
.d_kqfilter = beri_kqfilter,
.d_name = "beri ring buffer",
};
static int
parse_fdt(struct beri_softc *sc)
{
pcell_t dts_value[0];
phandle_t node;
int len;
if ((node = ofw_bus_get_node(sc->dev)) == -1)
return (ENXIO);
/* get device name */
if (OF_getprop(ofw_bus_get_node(sc->dev), "device_name",
&sc->devname, sizeof(sc->devname)) <= 0) {
device_printf(sc->dev, "Can't get device_name\n");
return (ENXIO);
}
if ((len = OF_getproplen(node, "data_size")) <= 0)
return (ENXIO);
OF_getencprop(node, "data_size", dts_value, len);
sc->data_size = dts_value[0];
if ((len = OF_getproplen(node, "data_read")) <= 0)
return (ENXIO);
OF_getencprop(node, "data_read", dts_value, len);
sc->data_read = dts_value[0];
if ((len = OF_getproplen(node, "data_write")) <= 0)
return (ENXIO);
OF_getencprop(node, "data_write", dts_value, len);
sc->data_write = dts_value[0];
if ((len = OF_getproplen(node, "control_read")) <= 0)
return (ENXIO);
OF_getencprop(node, "control_read", dts_value, len);
sc->control_read = dts_value[0];
if ((len = OF_getproplen(node, "control_write")) <= 0)
return (ENXIO);
OF_getencprop(node, "control_write", dts_value, len);
sc->control_write = dts_value[0];
return (0);
}
static int
beri_probe(device_t dev)
{
if (!ofw_bus_status_okay(dev))
return (ENXIO);
if (!ofw_bus_is_compatible(dev, "sri-cambridge,beri-ring"))
return (ENXIO);
device_set_desc(dev, "SRI-Cambridge BERI ring buffer");
return (BUS_PROBE_DEFAULT);
}
static int
beri_attach(device_t dev)
{
struct beri_softc *sc;
sc = device_get_softc(dev);
sc->dev = dev;
if (bus_alloc_resources(dev, beri_spec, sc->res)) {
device_printf(dev, "could not allocate resources\n");
return (ENXIO);
}
/* Memory interface */
sc->bst = rman_get_bustag(sc->res[0]);
sc->bsh = rman_get_bushandle(sc->res[0]);
if (parse_fdt(sc)) {
device_printf(sc->dev, "Can't get FDT values\n");
return (ENXIO);
}
sc->cdev = make_dev(&beri_cdevsw, 0, UID_ROOT, GID_WHEEL,
S_IRWXU, "%s", sc->devname);
if (sc->cdev == NULL) {
device_printf(dev, "Failed to create character device.\n");
return (ENXIO);
}
sc->cdev->si_drv1 = sc;
mtx_init(&sc->beri_mtx, "beri_mtx", NULL, MTX_DEF);
knlist_init_mtx(&sc->beri_rsel.si_note, &sc->beri_mtx);
return (0);
}
static device_method_t beri_methods[] = {
DEVMETHOD(device_probe, beri_probe),
DEVMETHOD(device_attach, beri_attach),
{ 0, 0 }
};
static driver_t beri_driver = {
"beri_ring",
beri_methods,
sizeof(struct beri_softc),
};
static devclass_t beri_devclass;
DRIVER_MODULE(beri_ring, simplebus, beri_driver, beri_devclass, 0, 0);