freebsd-skq/sys/arm/amlogic/aml8726/aml8726_clkmsr.c
Ganbold Tsagaankhuu c119629dd0 This modifies several FreeBSD drivers to use the GNU approach to
supply clk81 information.  It also changes the hardware strings
in some of the drivers to match what's present in the GNU files.

Submitted by:  John Wehle
Reviewed by:   imp
2015-04-11 08:34:41 +00:00

302 lines
7.8 KiB
C

/*-
* Copyright 2014-2015 John Wehle <john@feith.com>
* 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 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.
*
*/
/*
* Amlogic aml8726 clock measurement driver.
*
* This allows various clock rates to be determine at runtime.
* The measurements are done once and are not expected to change
* (i.e. FDT fixup provides clk81 as bus-frequency to the MMC
* and UART drivers which use the value when programming the
* hardware).
*/
#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/timetc.h>
#include <sys/timeet.h>
#include <machine/bus.h>
#include <machine/cpu.h>
#include <machine/fdt.h>
#include <dev/fdt/fdt_common.h>
#include <dev/ofw/ofw_bus.h>
#include <dev/ofw/ofw_bus_subr.h>
#include <arm/amlogic/aml8726/aml8726_soc.h>
#include <arm/amlogic/aml8726/aml8726_clkmsr.h>
static struct aml8726_clkmsr_clk {
const char * name;
uint32_t mux;
} aml8726_clkmsr_clks[] = {
{ "clk81", 7 },
};
#define AML_CLKMSR_CLK81 0
#define AML_CLKMSR_NCLKS (sizeof(aml8726_clkmsr_clks) \
/ sizeof(aml8726_clkmsr_clks[0]))
struct aml8726_clkmsr_softc {
device_t dev;
struct resource * res[1];
};
static struct resource_spec aml8726_clkmsr_spec[] = {
{ SYS_RES_MEMORY, 0, RF_ACTIVE },
{ -1, 0 }
};
/*
* Duration can range from 1uS to 65535 uS and should be chosen
* based on the expected frequency result so to maximize resolution
* and avoid overflowing the 16 bit result counter.
*/
#define AML_CLKMSR_DURATION 32
#define AML_CLKMSR_DUTY_REG 0
#define AML_CLKMSR_0_REG 4
#define AML_CLKMSR_0_BUSY (1U << 31)
#define AML_CLKMSR_0_MUX_MASK (0x3f << 20)
#define AML_CLKMSR_0_MUX_SHIFT 20
#define AML_CLKMSR_0_MUX_EN (1 << 19)
#define AML_CLKMSR_0_MEASURE (1 << 16)
#define AML_CLKMSR_0_DURATION_MASK 0xffff
#define AML_CLKMSR_0_DURATION_SHIFT 0
#define AML_CLKMSR_1_REG 8
#define AML_CLKMSR_2_REG 12
#define AML_CLKMSR_2_RESULT_MASK 0xffff
#define AML_CLKMSR_2_RESULT_SHIFT 0
#define CSR_WRITE_4(sc, reg, val) bus_write_4((sc)->res[0], reg, (val))
#define CSR_READ_4(sc, reg) bus_read_4((sc)->res[0], reg)
#define CSR_BARRIER(sc, reg) bus_barrier((sc)->res[0], reg, 4, \
(BUS_SPACE_BARRIER_READ | BUS_SPACE_BARRIER_WRITE))
static int
aml8726_clkmsr_clock_frequency(struct aml8726_clkmsr_softc *sc, unsigned clock)
{
uint32_t value;
if (clock >= AML_CLKMSR_NCLKS)
return (0);
/*
* Locking is not used as this is only expected to be called from
* FDT fixup (which occurs prior to driver initialization) or attach.
*/
CSR_WRITE_4(sc, AML_CLKMSR_0_REG, 0);
CSR_BARRIER(sc, AML_CLKMSR_0_REG);
value = (aml8726_clkmsr_clks[clock].mux << AML_CLKMSR_0_MUX_SHIFT)
| ((AML_CLKMSR_DURATION - 1) << AML_CLKMSR_0_DURATION_SHIFT)
| AML_CLKMSR_0_MUX_EN
| AML_CLKMSR_0_MEASURE;
CSR_WRITE_4(sc, AML_CLKMSR_0_REG, value);
CSR_BARRIER(sc, AML_CLKMSR_0_REG);
while ((CSR_READ_4(sc, AML_CLKMSR_0_REG) & AML_CLKMSR_0_BUSY) != 0)
cpu_spinwait();
value &= ~AML_CLKMSR_0_MEASURE;
CSR_WRITE_4(sc, AML_CLKMSR_0_REG, value);
CSR_BARRIER(sc, AML_CLKMSR_0_REG);
value = (((CSR_READ_4(sc, AML_CLKMSR_2_REG) & AML_CLKMSR_2_RESULT_MASK)
>> AML_CLKMSR_2_RESULT_SHIFT) + AML_CLKMSR_DURATION / 2) /
AML_CLKMSR_DURATION;
return value;
}
static void
aml8726_clkmsr_fixup_clk81(struct aml8726_clkmsr_softc *sc, int freq)
{
pcell_t prop;
ssize_t len;
phandle_t clk_node;
phandle_t node;
node = ofw_bus_get_node(sc->dev);
len = OF_getencprop(node, "clocks", &prop, sizeof(prop));
if ((len / sizeof(prop)) != 1 || prop == 0 ||
(clk_node = OF_node_from_xref(prop)) == 0)
return;
len = OF_getencprop(clk_node, "clock-frequency", &prop, sizeof(prop));
if ((len / sizeof(prop)) != 1 || prop != 0)
return;
freq = cpu_to_fdt32(freq);
OF_setprop(clk_node, "clock-frequency", (void *)&freq, sizeof(freq));
}
static int
aml8726_clkmsr_probe(device_t dev)
{
if (!ofw_bus_status_okay(dev))
return (ENXIO);
if (!ofw_bus_is_compatible(dev, "amlogic,aml8726-clkmsr"))
return (ENXIO);
device_set_desc(dev, "Amlogic aml8726 clkmsr");
return (BUS_PROBE_DEFAULT);
}
static int
aml8726_clkmsr_attach(device_t dev)
{
struct aml8726_clkmsr_softc *sc = device_get_softc(dev);
int freq;
sc->dev = dev;
if (bus_alloc_resources(dev, aml8726_clkmsr_spec, sc->res)) {
device_printf(dev, "can not allocate resources for device\n");
return (ENXIO);
}
freq = aml8726_clkmsr_clock_frequency(sc, AML_CLKMSR_CLK81);
device_printf(sc->dev, "bus clock %u MHz\n", freq);
aml8726_clkmsr_fixup_clk81(sc, freq * 1000000);
return (0);
}
static int
aml8726_clkmsr_detach(device_t dev)
{
struct aml8726_clkmsr_softc *sc = device_get_softc(dev);
bus_release_resources(dev, aml8726_clkmsr_spec, sc->res);
return (0);
}
static device_method_t aml8726_clkmsr_methods[] = {
/* Device interface */
DEVMETHOD(device_probe, aml8726_clkmsr_probe),
DEVMETHOD(device_attach, aml8726_clkmsr_attach),
DEVMETHOD(device_detach, aml8726_clkmsr_detach),
DEVMETHOD_END
};
static driver_t aml8726_clkmsr_driver = {
"clkmsr",
aml8726_clkmsr_methods,
sizeof(struct aml8726_clkmsr_softc),
};
static devclass_t aml8726_clkmsr_devclass;
EARLY_DRIVER_MODULE(clkmsr, simplebus, aml8726_clkmsr_driver,
aml8726_clkmsr_devclass, 0, 0, BUS_PASS_CPU + BUS_PASS_ORDER_EARLY);
int
aml8726_clkmsr_bus_frequency()
{
struct resource mem;
struct aml8726_clkmsr_softc sc;
phandle_t node;
u_long pbase, psize;
u_long start, size;
int freq;
KASSERT(aml8726_soc_hw_rev != AML_SOC_HW_REV_UNKNOWN,
("aml8726_soc_hw_rev isn't initialized"));
/*
* Try to access the clkmsr node directly i.e. through /aliases/.
*/
if ((node = OF_finddevice("clkmsr")) != 0)
if (fdt_is_compatible_strict(node, "amlogic,aml8726-clkmsr"))
goto moveon;
/*
* Find the node the long way.
*/
if ((node = OF_finddevice("/soc")) == 0)
return (0);
if ((node = fdt_find_compatible(node,
"amlogic,aml8726-clkmsr", 1)) == 0)
return (0);
moveon:
if (fdt_get_range(OF_parent(node), 0, &pbase, &psize) != 0
|| fdt_regsize(node, &start, &size) != 0)
return (0);
start += pbase;
memset(&mem, 0, sizeof(mem));
mem.r_bustag = fdtbus_bs_tag;
if (bus_space_map(mem.r_bustag, start, size, 0, &mem.r_bushandle) != 0)
return (0);
/*
* Build an incomplete (however sufficient for the purpose
* of calling aml8726_clkmsr_clock_frequency) softc.
*/
memset(&sc, 0, sizeof(sc));
sc.res[0] = &mem;
freq = aml8726_clkmsr_clock_frequency(&sc, AML_CLKMSR_CLK81) * 1000000;
bus_space_unmap(mem.r_bustag, mem.r_bushandle, size);
return (freq);
}