freebsd-dev/sys/arm/at91/at91_pmc.c
2007-01-05 01:14:14 +00:00

425 lines
10 KiB
C

/*-
* Copyright (c) 2006 M. Warner Losh. All rights reserved.
*
* 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 ``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 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.
*/
#include "opt_at91.h"
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/kernel.h>
#include <sys/module.h>
#include <sys/time.h>
#include <sys/bus.h>
#include <sys/resource.h>
#include <sys/rman.h>
#include <sys/timetc.h>
#include <machine/bus.h>
#include <machine/cpu.h>
#include <machine/cpufunc.h>
#include <machine/resource.h>
#include <machine/frame.h>
#include <machine/intr.h>
#include <arm/at91/at91rm92reg.h>
#include <arm/at91/at91_pmcreg.h>
#include <arm/at91/at91_pmcvar.h>
static struct at91_pmc_softc {
bus_space_tag_t sc_st;
bus_space_handle_t sc_sh;
struct resource *mem_res; /* Memory resource */
device_t dev;
int main_clock_hz;
uint32_t pllb_init;
} *pmc_softc;
static void at91_pmc_set_pllb_mode(struct at91_pmc_clock *, int);
static void at91_pmc_set_sys_mode(struct at91_pmc_clock *, int);
static void at91_pmc_set_periph_mode(struct at91_pmc_clock *, int);
static struct at91_pmc_clock slck = {
.name = "slck", // 32,768 Hz slow clock
.hz = 32768,
.refcnt = 1,
.id = 0,
.primary = 1,
};
static struct at91_pmc_clock main_ck = {
.name = "main", // Main clock
.refcnt = 0,
.id = 1,
.primary = 1,
.pmc_mask = PMC_IER_MOSCS,
};
static struct at91_pmc_clock plla = {
.name = "plla", // PLLA Clock, used for CPU clocking
.parent = &main_ck,
.refcnt = 1,
.id = 0,
.primary = 1,
.pll = 1,
.pmc_mask = PMC_IER_LOCKA,
};
static struct at91_pmc_clock pllb = {
.name = "pllb", // PLLB Clock, used for USB functions
.parent = &main_ck,
.refcnt = 0,
.id = 0,
.primary = 1,
.pll = 1,
.pmc_mask = PMC_IER_LOCKB,
.set_mode = &at91_pmc_set_pllb_mode,
};
static struct at91_pmc_clock udpck = {
.name = "udpck",
.parent = &pllb,
.pmc_mask = PMC_SCER_UDP,
.set_mode = at91_pmc_set_sys_mode
};
static struct at91_pmc_clock uhpck = {
.name = "uhpck",
.parent = &pllb,
.pmc_mask = PMC_SCER_UHP,
.set_mode = at91_pmc_set_sys_mode
};
static struct at91_pmc_clock mck = {
.name = "mck",
.pmc_mask = PMC_IER_MCKRDY,
.refcnt = 0,
};
static struct at91_pmc_clock udc_clk = {
.name = "udc_clk",
.parent = &mck,
.pmc_mask = 1 << AT91RM92_IRQ_UDP,
.set_mode = &at91_pmc_set_periph_mode
};
static struct at91_pmc_clock ohci_clk = {
.name = "ohci_clk",
.parent = &mck,
.pmc_mask = 1 << AT91RM92_IRQ_UDP,
.set_mode = &at91_pmc_set_periph_mode
};
static struct at91_pmc_clock *const clock_list[] = {
&slck,
&main_ck,
&plla,
&pllb,
&udpck,
&uhpck,
&mck,
&udc_clk,
&ohci_clk
};
static inline uint32_t
RD4(struct at91_pmc_softc *sc, bus_size_t off)
{
return bus_read_4(sc->mem_res, off);
}
static inline void
WR4(struct at91_pmc_softc *sc, bus_size_t off, uint32_t val)
{
bus_write_4(sc->mem_res, off, val);
}
static void
at91_pmc_set_pllb_mode(struct at91_pmc_clock *clk, int on)
{
struct at91_pmc_softc *sc = pmc_softc;
uint32_t value;
printf("Turning PLLB %#x %s\n", sc->pllb_init, on ? "on" : "off");
if (on) {
on = PMC_IER_LOCKB;
value = sc->pllb_init;
} else {
value = 0;
}
WR4(sc, CKGR_PLLBR, value);
while ((RD4(sc, PMC_SR) & PMC_IER_LOCKB) != on)
continue;
printf("Done!\n");
}
static void
at91_pmc_set_sys_mode(struct at91_pmc_clock *clk, int on)
{
struct at91_pmc_softc *sc = pmc_softc;
printf("Turning SC %#x %s\n", clk->pmc_mask, on ? "on" : "off");
WR4(sc, on ? PMC_SCER : PMC_SCDR, clk->pmc_mask);
if (on)
while ((RD4(sc, PMC_SCSR) & clk->pmc_mask) != clk->pmc_mask)
continue;
else
while ((RD4(sc, PMC_SCSR) & clk->pmc_mask) == clk->pmc_mask)
continue;
printf("Done SCSR is now: %#x!\n", RD4(sc, PMC_SCSR));
}
static void
at91_pmc_set_periph_mode(struct at91_pmc_clock *clk, int on)
{
struct at91_pmc_softc *sc = pmc_softc;
printf("Turning PC %#x %s\n", clk->pmc_mask, on ? "on" : "off");
WR4(sc, on ? PMC_PCER : PMC_PCDR, clk->pmc_mask);
if (on)
while ((RD4(sc, PMC_PCSR) & clk->pmc_mask) != clk->pmc_mask)
continue;
else
while ((RD4(sc, PMC_PCSR) & clk->pmc_mask) == clk->pmc_mask)
continue;
printf("Done PCSR is now: %#x!\n", RD4(sc, PMC_PCSR));
}
struct at91_pmc_clock *
at91_pmc_clock_ref(const char *name)
{
int i;
for (i = 0; i < sizeof(clock_list) / sizeof(clock_list[0]); i++)
if (strcmp(name, clock_list[i]->name) == 0)
return (clock_list[i]);
return (NULL);
}
void
at91_pmc_clock_deref(struct at91_pmc_clock *clk)
{
}
void
at91_pmc_clock_enable(struct at91_pmc_clock *clk)
{
/* XXX LOCKING? XXX */
printf("Enable %s\n", clk->name);
if (clk->parent)
at91_pmc_clock_enable(clk->parent);
if (clk->refcnt++ == 0 && clk->set_mode)
clk->set_mode(clk, 1);
}
void
at91_pmc_clock_disable(struct at91_pmc_clock *clk)
{
/* XXX LOCKING? XXX */
if (--clk->refcnt == 0 && clk->set_mode)
clk->set_mode(clk, 0);
if (clk->parent)
at91_pmc_clock_disable(clk->parent);
}
static int
at91_pmc_pll_rate(int freq, uint32_t reg, int is_pllb)
{
uint32_t mul, div;
div = reg & 0xff;
mul = (reg >> 16) & 0x7ff;
if (div != 0 && mul != 0) {
freq /= div;
freq *= mul + 1;
} else {
freq = 0;
}
if (is_pllb && (reg & (1 << 28)))
freq >>= 1;
return (freq);
}
static uint32_t
at91_pmc_pll_calc(uint32_t main_freq, uint32_t out_freq)
{
uint32_t i, div = 0, mul = 0, diff = 1 << 30;
unsigned ret = (out_freq > PMC_PLL_FAST_THRESH) ? 0xbe00 : 0x3e00;
if (out_freq > PMC_PLL_MAX_OUT_FREQ)
goto fail;
for (i = 1; i < 256; i++) {
int32_t diff1;
uint32_t input, mul1;
input = main_freq / i;
if (input < PMC_PLL_MIN_IN_FREQ)
break;
if (input > PMC_PLL_MAX_IN_FREQ)
continue;
mul1 = out_freq / input;
if (mul1 > PMC_PLL_MULT_MAX)
continue;
if (mul1 < PMC_PLL_MULT_MIN)
break;
diff1 = out_freq - input * mul1;
if (diff1 < 0)
diff1 = -diff1;
if (diff > diff1) {
diff = diff1;
div = i;
mul = mul1;
if (diff == 0)
break;
}
}
if (diff > (out_freq >> PMC_PLL_SHIFT_TOL))
goto fail;
return ret | ((mul - 1) << 16) | div;
fail:
return 0;
}
static void
at91_pmc_init_clock(struct at91_pmc_softc *sc, int main_clock)
{
uint32_t mckr;
int freq;
sc->main_clock_hz = main_clock;
main_ck.hz = main_clock;
plla.hz = at91_pmc_pll_rate(main_clock, RD4(sc, CKGR_PLLAR), 0);
/*
* Initialize the usb clock. This sets up pllb, but disables the
* actual clock.
*/
sc->pllb_init = at91_pmc_pll_calc(main_clock, 48000000 * 2) |0x10000000;
pllb.hz = at91_pmc_pll_rate(main_clock, sc->pllb_init, 1);
WR4(sc, PMC_PCDR, (1 << AT91RM92_IRQ_UHP) | (1 << AT91RM92_IRQ_UDP));
WR4(sc, PMC_SCDR, PMC_SCER_UHP | PMC_SCER_UDP);
WR4(sc, CKGR_PLLBR, 0);
WR4(sc, PMC_SCER, PMC_SCER_MCKUDP);
/*
* MCK and PCU derive from one of the primary clocks. Initialize
* this relationship.
*/
mckr = RD4(sc, PMC_MCKR);
mck.parent = clock_list[mckr & 0x3];
mck.parent->refcnt++;
freq = mck.parent->hz / (1 << ((mckr >> 2) & 3));
mck.hz = freq / (1 + ((mckr >> 8) & 3));
device_printf(sc->dev,
"Primary: %d Hz PLLA: %d MHz CPU: %d MHz MCK: %d MHz\n",
sc->main_clock_hz,
at91_pmc_pll_rate(main_clock, RD4(sc, CKGR_PLLAR), 0) / 1000000,
freq / 1000000, mck.hz / 1000000);
WR4(sc, PMC_SCDR, PMC_SCER_PCK0 | PMC_SCER_PCK1 | PMC_SCER_PCK2 |
PMC_SCER_PCK3);
/* XXX kludge, turn on all peripherals */
WR4(sc, PMC_PCER, 0xffffffff);
/* Disable all interrupts for PMC */
WR4(sc, PMC_IDR, 0xffffffff);
}
static void
at91_pmc_deactivate(device_t dev)
{
struct at91_pmc_softc *sc;
sc = device_get_softc(dev);
bus_generic_detach(sc->dev);
if (sc->mem_res)
bus_release_resource(dev, SYS_RES_IOPORT,
rman_get_rid(sc->mem_res), sc->mem_res);
sc->mem_res = 0;
return;
}
static int
at91_pmc_activate(device_t dev)
{
struct at91_pmc_softc *sc;
int rid;
sc = device_get_softc(dev);
rid = 0;
sc->mem_res = bus_alloc_resource_any(dev, SYS_RES_MEMORY, &rid,
RF_ACTIVE);
if (sc->mem_res == NULL)
goto errout;
return (0);
errout:
at91_pmc_deactivate(dev);
return (ENOMEM);
}
static int
at91_pmc_probe(device_t dev)
{
device_set_desc(dev, "PMC");
return (0);
}
static int
at91_pmc_attach(device_t dev)
{
int err;
pmc_softc = device_get_softc(dev);
pmc_softc->dev = dev;
if ((err = at91_pmc_activate(dev)) != 0)
return err;
#if defined(AT91_TSC) | defined (AT91_BWCT)
at91_pmc_init_clock(pmc_softc, 16000000);
#else
at91_pmc_init_clock(pmc_softc, 10000000);
#endif
return (0);
}
static device_method_t at91_pmc_methods[] = {
DEVMETHOD(device_probe, at91_pmc_probe),
DEVMETHOD(device_attach, at91_pmc_attach),
{0, 0},
};
static driver_t at91_pmc_driver = {
"at91_pmc",
at91_pmc_methods,
sizeof(struct at91_pmc_softc),
};
static devclass_t at91_pmc_devclass;
DRIVER_MODULE(at91_pmc, atmelarm, at91_pmc_driver, at91_pmc_devclass, 0, 0);