linux/drivers/clk/pxa/clk-pxa25x.c
Robert Jarzmik 9fe6942950 clk: pxa: transfer CPU clock setting from pxa2xx-cpufreq
This is the initial stage to transfer the pxa25x and pxa27x CPU clocks
handling from cpufreq to the clock API. More precisely, the clocks
transferred are :
 - cpll : core pll, known also as the CPU core turbo frequency
 - core : core, known also as the CPU actual frequency, being either the
          CPU core turbo frequency or the CPU core run frequency

This transfer is a prequel to shrink the code in pxa2xx-cpufreq.c, so
that it can become, at least in devicetree builds, the casual cpufreq-dt
driver.

Signed-off-by: Robert Jarzmik <robert.jarzmik@free.fr>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2016-11-04 13:25:03 -07:00

363 lines
11 KiB
C

/*
* Marvell PXA25x family clocks
*
* Copyright (C) 2014 Robert Jarzmik
*
* Heavily inspired from former arch/arm/mach-pxa/pxa25x.c.
*
* 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; version 2 of the License.
*
* For non-devicetree platforms. Once pxa is fully converted to devicetree, this
* should go away.
*/
#include <linux/clk-provider.h>
#include <linux/clk.h>
#include <linux/clkdev.h>
#include <linux/io.h>
#include <linux/of.h>
#include <mach/pxa2xx-regs.h>
#include <mach/smemc.h>
#include <dt-bindings/clock/pxa-clock.h>
#include "clk-pxa.h"
#define KHz 1000
#define MHz (1000 * 1000)
enum {
PXA_CORE_RUN = 0,
PXA_CORE_TURBO,
};
#define PXA25x_CLKCFG(T) \
(CLKCFG_FCS | \
((T) ? CLKCFG_TURBO : 0))
#define PXA25x_CCCR(N2, M, L) (N2 << 7 | M << 5 | L)
#define MDCNFG_DRAC2(mdcnfg) (((mdcnfg) >> 21) & 0x3)
#define MDCNFG_DRAC0(mdcnfg) (((mdcnfg) >> 5) & 0x3)
/* Define the refresh period in mSec for the SDRAM and the number of rows */
#define SDRAM_TREF 64 /* standard 64ms SDRAM */
/*
* Various clock factors driven by the CCCR register.
*/
/* Crystal Frequency to Memory Frequency Multiplier (L) */
static unsigned char L_clk_mult[32] = { 0, 27, 32, 36, 40, 45, 0, };
/* Memory Frequency to Run Mode Frequency Multiplier (M) */
static unsigned char M_clk_mult[4] = { 0, 1, 2, 4 };
/* Run Mode Frequency to Turbo Mode Frequency Multiplier (N) */
/* Note: we store the value N * 2 here. */
static unsigned char N2_clk_mult[8] = { 0, 0, 2, 3, 4, 0, 6, 0 };
static const char * const get_freq_khz[] = {
"core", "run", "cpll", "memory"
};
static int get_sdram_rows(void)
{
static int sdram_rows;
unsigned int drac2 = 0, drac0 = 0;
u32 mdcnfg;
if (sdram_rows)
return sdram_rows;
mdcnfg = readl_relaxed(MDCNFG);
if (mdcnfg & (MDCNFG_DE2 | MDCNFG_DE3))
drac2 = MDCNFG_DRAC2(mdcnfg);
if (mdcnfg & (MDCNFG_DE0 | MDCNFG_DE1))
drac0 = MDCNFG_DRAC0(mdcnfg);
sdram_rows = 1 << (11 + max(drac0, drac2));
return sdram_rows;
}
static u32 mdrefr_dri(unsigned int freq_khz)
{
u32 interval = freq_khz * SDRAM_TREF / get_sdram_rows();
return interval / 32;
}
/*
* Get the clock frequency as reflected by CCCR and the turbo flag.
* We assume these values have been applied via a fcs.
* If info is not 0 we also display the current settings.
*/
unsigned int pxa25x_get_clk_frequency_khz(int info)
{
struct clk *clk;
unsigned long clks[5];
int i;
for (i = 0; i < ARRAY_SIZE(get_freq_khz); i++) {
clk = clk_get(NULL, get_freq_khz[i]);
if (IS_ERR(clk)) {
clks[i] = 0;
} else {
clks[i] = clk_get_rate(clk);
clk_put(clk);
}
}
if (info) {
pr_info("Run Mode clock: %ld.%02ldMHz\n",
clks[1] / 1000000, (clks[1] % 1000000) / 10000);
pr_info("Turbo Mode clock: %ld.%02ldMHz\n",
clks[2] / 1000000, (clks[2] % 1000000) / 10000);
pr_info("Memory clock: %ld.%02ldMHz\n",
clks[3] / 1000000, (clks[3] % 1000000) / 10000);
}
return (unsigned int)clks[0] / KHz;
}
static unsigned long clk_pxa25x_memory_get_rate(struct clk_hw *hw,
unsigned long parent_rate)
{
unsigned long cccr = readl(CCCR);
unsigned int m = M_clk_mult[(cccr >> 5) & 0x03];
return parent_rate / m;
}
PARENTS(clk_pxa25x_memory) = { "run" };
RATE_RO_OPS(clk_pxa25x_memory, "memory");
PARENTS(pxa25x_pbus95) = { "ppll_95_85mhz", "ppll_95_85mhz" };
PARENTS(pxa25x_pbus147) = { "ppll_147_46mhz", "ppll_147_46mhz" };
PARENTS(pxa25x_osc3) = { "osc_3_6864mhz", "osc_3_6864mhz" };
#define PXA25X_CKEN(dev_id, con_id, parents, mult, div, \
bit, is_lp, flags) \
PXA_CKEN(dev_id, con_id, bit, parents, mult, div, mult, div, \
is_lp, CKEN, CKEN_ ## bit, flags)
#define PXA25X_PBUS95_CKEN(dev_id, con_id, bit, mult_hp, div_hp, delay) \
PXA25X_CKEN(dev_id, con_id, pxa25x_pbus95_parents, mult_hp, \
div_hp, bit, NULL, 0)
#define PXA25X_PBUS147_CKEN(dev_id, con_id, bit, mult_hp, div_hp, delay)\
PXA25X_CKEN(dev_id, con_id, pxa25x_pbus147_parents, mult_hp, \
div_hp, bit, NULL, 0)
#define PXA25X_OSC3_CKEN(dev_id, con_id, bit, mult_hp, div_hp, delay) \
PXA25X_CKEN(dev_id, con_id, pxa25x_osc3_parents, mult_hp, \
div_hp, bit, NULL, 0)
#define PXA25X_CKEN_1RATE(dev_id, con_id, bit, parents, delay) \
PXA_CKEN_1RATE(dev_id, con_id, bit, parents, \
CKEN, CKEN_ ## bit, 0)
#define PXA25X_CKEN_1RATE_AO(dev_id, con_id, bit, parents, delay) \
PXA_CKEN_1RATE(dev_id, con_id, bit, parents, \
CKEN, CKEN_ ## bit, CLK_IGNORE_UNUSED)
static struct desc_clk_cken pxa25x_clocks[] __initdata = {
PXA25X_PBUS95_CKEN("pxa2xx-mci.0", NULL, MMC, 1, 5, 0),
PXA25X_PBUS95_CKEN("pxa2xx-i2c.0", NULL, I2C, 1, 3, 0),
PXA25X_PBUS95_CKEN("pxa2xx-ir", "FICPCLK", FICP, 1, 2, 0),
PXA25X_PBUS95_CKEN("pxa25x-udc", NULL, USB, 1, 2, 5),
PXA25X_PBUS147_CKEN("pxa2xx-uart.0", NULL, FFUART, 1, 10, 1),
PXA25X_PBUS147_CKEN("pxa2xx-uart.1", NULL, BTUART, 1, 10, 1),
PXA25X_PBUS147_CKEN("pxa2xx-uart.2", NULL, STUART, 1, 10, 1),
PXA25X_PBUS147_CKEN("pxa2xx-uart.3", NULL, HWUART, 1, 10, 1),
PXA25X_PBUS147_CKEN("pxa2xx-i2s", NULL, I2S, 1, 10, 0),
PXA25X_PBUS147_CKEN(NULL, "AC97CLK", AC97, 1, 12, 0),
PXA25X_OSC3_CKEN("pxa25x-ssp.0", NULL, SSP, 1, 1, 0),
PXA25X_OSC3_CKEN("pxa25x-nssp.1", NULL, NSSP, 1, 1, 0),
PXA25X_OSC3_CKEN("pxa25x-nssp.2", NULL, ASSP, 1, 1, 0),
PXA25X_OSC3_CKEN("pxa25x-pwm.0", NULL, PWM0, 1, 1, 0),
PXA25X_OSC3_CKEN("pxa25x-pwm.1", NULL, PWM1, 1, 1, 0),
PXA25X_CKEN_1RATE("pxa2xx-fb", NULL, LCD, clk_pxa25x_memory_parents, 0),
PXA25X_CKEN_1RATE_AO("pxa2xx-pcmcia", NULL, MEMC,
clk_pxa25x_memory_parents, 0),
};
/*
* In this table, PXA25x_CCCR(N2, M, L) has the following meaning, where :
* - freq_cpll = n * m * L * 3.6864 MHz
* - n = N2 / 2
* - m = 2^(M - 1), where 1 <= M <= 3
* - l = L_clk_mult[L], ie. { 0, 27, 32, 36, 40, 45, 0, }[L]
*/
static struct pxa2xx_freq pxa25x_freqs[] = {
/* CPU MEMBUS CCCR DIV2 CCLKCFG */
{ 99532800, 99500, PXA25x_CCCR(2, 1, 1), 1, PXA25x_CLKCFG(1)},
{199065600, 99500, PXA25x_CCCR(4, 1, 1), 0, PXA25x_CLKCFG(1)},
{298598400, 99500, PXA25x_CCCR(3, 2, 1), 0, PXA25x_CLKCFG(1)},
{398131200, 99500, PXA25x_CCCR(4, 2, 1), 0, PXA25x_CLKCFG(1)},
};
static u8 clk_pxa25x_core_get_parent(struct clk_hw *hw)
{
unsigned long clkcfg;
unsigned int t;
asm("mrc\tp14, 0, %0, c6, c0, 0" : "=r" (clkcfg));
t = clkcfg & (1 << 0);
if (t)
return PXA_CORE_TURBO;
return PXA_CORE_RUN;
}
static int clk_pxa25x_core_set_parent(struct clk_hw *hw, u8 index)
{
if (index > PXA_CORE_TURBO)
return -EINVAL;
pxa2xx_core_turbo_switch(index == PXA_CORE_TURBO);
return 0;
}
static int clk_pxa25x_core_determine_rate(struct clk_hw *hw,
struct clk_rate_request *req)
{
return __clk_mux_determine_rate(hw, req);
}
PARENTS(clk_pxa25x_core) = { "run", "cpll" };
MUX_OPS(clk_pxa25x_core, "core", CLK_SET_RATE_PARENT);
static unsigned long clk_pxa25x_run_get_rate(struct clk_hw *hw,
unsigned long parent_rate)
{
unsigned long cccr = readl(CCCR);
unsigned int n2 = N2_clk_mult[(cccr >> 7) & 0x07];
return (parent_rate / n2) * 2;
}
PARENTS(clk_pxa25x_run) = { "cpll" };
RATE_RO_OPS(clk_pxa25x_run, "run");
static unsigned long clk_pxa25x_cpll_get_rate(struct clk_hw *hw,
unsigned long parent_rate)
{
unsigned long clkcfg, cccr = readl(CCCR);
unsigned int l, m, n2, t;
asm("mrc\tp14, 0, %0, c6, c0, 0" : "=r" (clkcfg));
t = clkcfg & (1 << 0);
l = L_clk_mult[(cccr >> 0) & 0x1f];
m = M_clk_mult[(cccr >> 5) & 0x03];
n2 = N2_clk_mult[(cccr >> 7) & 0x07];
return m * l * n2 * parent_rate / 2;
}
static int clk_pxa25x_cpll_determine_rate(struct clk_hw *hw,
struct clk_rate_request *req)
{
return pxa2xx_determine_rate(req, pxa25x_freqs,
ARRAY_SIZE(pxa25x_freqs));
}
static int clk_pxa25x_cpll_set_rate(struct clk_hw *hw, unsigned long rate,
unsigned long parent_rate)
{
int i;
pr_debug("%s(rate=%lu parent_rate=%lu)\n", __func__, rate, parent_rate);
for (i = 0; i < ARRAY_SIZE(pxa25x_freqs); i++)
if (pxa25x_freqs[i].cpll == rate)
break;
if (i >= ARRAY_SIZE(pxa25x_freqs))
return -EINVAL;
pxa2xx_cpll_change(&pxa25x_freqs[i], mdrefr_dri, MDREFR, CCCR);
return 0;
}
PARENTS(clk_pxa25x_cpll) = { "osc_3_6864mhz" };
RATE_OPS(clk_pxa25x_cpll, "cpll");
static void __init pxa25x_register_core(void)
{
clkdev_pxa_register(CLK_NONE, "cpll", NULL,
clk_register_clk_pxa25x_cpll());
clkdev_pxa_register(CLK_NONE, "run", NULL,
clk_register_clk_pxa25x_run());
clkdev_pxa_register(CLK_CORE, "core", NULL,
clk_register_clk_pxa25x_core());
}
static void __init pxa25x_register_plls(void)
{
clk_register_fixed_rate(NULL, "osc_3_6864mhz", NULL,
CLK_GET_RATE_NOCACHE, 3686400);
clk_register_fixed_rate(NULL, "osc_32_768khz", NULL,
CLK_GET_RATE_NOCACHE, 32768);
clk_register_fixed_rate(NULL, "clk_dummy", NULL, 0, 0);
clk_register_fixed_factor(NULL, "ppll_95_85mhz", "osc_3_6864mhz",
0, 26, 1);
clk_register_fixed_factor(NULL, "ppll_147_46mhz", "osc_3_6864mhz",
0, 40, 1);
}
static void __init pxa25x_base_clocks_init(void)
{
pxa25x_register_plls();
pxa25x_register_core();
clkdev_pxa_register(CLK_NONE, "system_bus", NULL,
clk_register_clk_pxa25x_memory());
}
#define DUMMY_CLK(_con_id, _dev_id, _parent) \
{ .con_id = _con_id, .dev_id = _dev_id, .parent = _parent }
struct dummy_clk {
const char *con_id;
const char *dev_id;
const char *parent;
};
static struct dummy_clk dummy_clks[] __initdata = {
DUMMY_CLK(NULL, "pxa25x-gpio", "osc_32_768khz"),
DUMMY_CLK(NULL, "pxa26x-gpio", "osc_32_768khz"),
DUMMY_CLK("GPIO11_CLK", NULL, "osc_3_6864mhz"),
DUMMY_CLK("GPIO12_CLK", NULL, "osc_32_768khz"),
DUMMY_CLK(NULL, "sa1100-rtc", "osc_32_768khz"),
DUMMY_CLK("OSTIMER0", NULL, "osc_32_768khz"),
DUMMY_CLK("UARTCLK", "pxa2xx-ir", "STUART"),
};
static void __init pxa25x_dummy_clocks_init(void)
{
struct clk *clk;
struct dummy_clk *d;
const char *name;
int i;
/*
* All pinctrl logic has been wiped out of the clock driver, especially
* for gpio11 and gpio12 outputs. Machine code should ensure proper pin
* control (ie. pxa2xx_mfp_config() invocation).
*/
for (i = 0; i < ARRAY_SIZE(dummy_clks); i++) {
d = &dummy_clks[i];
name = d->dev_id ? d->dev_id : d->con_id;
clk = clk_register_fixed_factor(NULL, name, d->parent, 0, 1, 1);
clk_register_clkdev(clk, d->con_id, d->dev_id);
}
}
int __init pxa25x_clocks_init(void)
{
pxa25x_base_clocks_init();
pxa25x_dummy_clocks_init();
return clk_pxa_cken_init(pxa25x_clocks, ARRAY_SIZE(pxa25x_clocks));
}
static void __init pxa25x_dt_clocks_init(struct device_node *np)
{
pxa25x_clocks_init();
clk_pxa_dt_common_init(np);
}
CLK_OF_DECLARE(pxa25x_clks, "marvell,pxa250-core-clocks",
pxa25x_dt_clocks_init);