/*
* Emma Mobile EV2 clock framework support
*
* Copyright (C) 2012 Magnus Damm
*
* 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.
*
* 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, write to the Free Software
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/io.h>
#include <linux/sh_clk.h>
#include <linux/clkdev.h>
#include <mach/common.h>
#define EMEV2_SMU_BASE 0xe0110000
/* EMEV2 SMU registers */
#define USIAU0_RSTCTRL 0x094
#define USIBU1_RSTCTRL 0x0ac
#define USIBU2_RSTCTRL 0x0b0
#define USIBU3_RSTCTRL 0x0b4
#define STI_RSTCTRL 0x124
#define USIAU0GCLKCTRL 0x4a0
#define USIBU1GCLKCTRL 0x4b8
#define USIBU2GCLKCTRL 0x4bc
#define USIBU3GCLKCTRL 0x04c0
#define STIGCLKCTRL 0x528
#define USIAU0SCLKDIV 0x61c
#define USIB2SCLKDIV 0x65c
#define USIB3SCLKDIV 0x660
#define STI_CLKSEL 0x688
#define SMU_GENERAL_REG0 0x7c0
/* not pretty, but hey */
static void __iomem *smu_base;
static void emev2_smu_write(unsigned long value, int offs)
{
BUG_ON(!smu_base || (offs >= PAGE_SIZE));
iowrite32(value, smu_base + offs);
}
void emev2_set_boot_vector(unsigned long value)
{
emev2_smu_write(value, SMU_GENERAL_REG0);
}
static struct clk_mapping smu_mapping = {
.phys = EMEV2_SMU_BASE,
.len = PAGE_SIZE,
};
/* Fixed 32 KHz root clock from C32K pin */
static struct clk c32k_clk = {
.rate = 32768,
.mapping = &smu_mapping,
};
/* PLL3 multiplies C32K with 7000 */
static unsigned long pll3_recalc(struct clk *clk)
{
return clk->parent->rate * 7000;
}
static struct sh_clk_ops pll3_clk_ops = {
.recalc = pll3_recalc,
};
static struct clk pll3_clk = {
.ops = &pll3_clk_ops,
.parent = &c32k_clk,
};
static struct clk *main_clks[] = {
&c32k_clk,
&pll3_clk,
};
enum { SCLKDIV_USIAU0, SCLKDIV_USIBU2, SCLKDIV_USIBU1, SCLKDIV_USIBU3,
SCLKDIV_NR };
#define SCLKDIV(_reg, _shift) \
{ \
.parent = &pll3_clk, \
.enable_reg = IOMEM(EMEV2_SMU_BASE + (_reg)), \
.enable_bit = _shift, \
}
static struct clk sclkdiv_clks[SCLKDIV_NR] = {
[SCLKDIV_USIAU0] = SCLKDIV(USIAU0SCLKDIV, 0),
[SCLKDIV_USIBU2] = SCLKDIV(USIB2SCLKDIV, 16),
[SCLKDIV_USIBU1] = SCLKDIV(USIB2SCLKDIV, 0),
[SCLKDIV_USIBU3] = SCLKDIV(USIB3SCLKDIV, 0),
};
enum { GCLK_USIAU0_SCLK, GCLK_USIBU1_SCLK, GCLK_USIBU2_SCLK, GCLK_USIBU3_SCLK,
GCLK_STI_SCLK,
GCLK_NR };
#define GCLK_SCLK(_parent, _reg) \
{ \
.parent = _parent, \
.enable_reg = IOMEM(EMEV2_SMU_BASE + (_reg)), \
.enable_bit = 1, /* SCLK_GCC */ \
}
static struct clk gclk_clks[GCLK_NR] = {
[GCLK_USIAU0_SCLK] = GCLK_SCLK(&sclkdiv_clks[SCLKDIV_USIAU0],
USIAU0GCLKCTRL),
[GCLK_USIBU1_SCLK] = GCLK_SCLK(&sclkdiv_clks[SCLKDIV_USIBU1],
USIBU1GCLKCTRL),
[GCLK_USIBU2_SCLK] = GCLK_SCLK(&sclkdiv_clks[SCLKDIV_USIBU2],
USIBU2GCLKCTRL),
[GCLK_USIBU3_SCLK] = GCLK_SCLK(&sclkdiv_clks[SCLKDIV_USIBU3],
USIBU3GCLKCTRL),
[GCLK_STI_SCLK] = GCLK_SCLK(&c32k_clk, STIGCLKCTRL),
};
static int emev2_gclk_enable(struct clk *clk)
{
iowrite32(ioread32(clk->mapped_reg) | (1 << clk->enable_bit),
clk->mapped_reg);
return 0;
}
static void emev2_gclk_disable(struct clk *clk)
{
iowrite32(ioread32(clk->mapped_reg) & ~(1 << clk->enable_bit),
clk->mapped_reg);
}
static struct sh_clk_ops emev2_gclk_clk_ops = {
.enable = emev2_gclk_enable,
.disable = emev2_gclk_disable,
.recalc = followparent_recalc,
};
static int __init emev2_gclk_register(struct clk *clks, int nr)
{
struct clk *clkp;
int ret = 0;
int k;
for (k = 0; !ret && (k < nr); k++) {
clkp = clks + k;
clkp->ops = &emev2_gclk_clk_ops;
ret |= clk_register(clkp);
}
return ret;
}
static unsigned long emev2_sclkdiv_recalc(struct clk *clk)
{
unsigned int sclk_div;
sclk_div = (ioread32(clk->mapped_reg) >> clk->enable_bit) & 0xff;
return clk->parent->rate / (sclk_div + 1);
}
static struct sh_clk_ops emev2_sclkdiv_clk_ops = {
.recalc = emev2_sclkdiv_recalc,
};
static int __init emev2_sclkdiv_register(struct clk *clks, int nr)
{
struct clk *clkp;
int ret = 0;
int k;
for (k = 0; !ret && (k < nr); k++) {
clkp = clks + k;
clkp->ops = &emev2_sclkdiv_clk_ops;
ret |= clk_register(clkp);
}
return ret;
}
static struct clk_lookup lookups[] = {
CLKDEV_DEV_ID("serial8250-em.0", &gclk_clks[GCLK_USIAU0_SCLK]),
CLKDEV_DEV_ID("e1020000.uart", &gclk_clks[GCLK_USIAU0_SCLK]),
CLKDEV_DEV_ID("serial8250-em.1", &gclk_clks[GCLK_USIBU1_SCLK]),
CLKDEV_DEV_ID("e1030000.uart", &gclk_clks[GCLK_USIBU1_SCLK]),
CLKDEV_DEV_ID("serial8250-em.2", &gclk_clks[GCLK_USIBU2_SCLK]),
CLKDEV_DEV_ID("e1040000.uart", &gclk_clks[GCLK_USIBU2_SCLK]),
CLKDEV_DEV_ID("serial8250-em.3", &gclk_clks[GCLK_USIBU3_SCLK]),
CLKDEV_DEV_ID("e1050000.uart", &gclk_clks[GCLK_USIBU3_SCLK]),
CLKDEV_DEV_ID("em_sti.0", &gclk_clks[GCLK_STI_SCLK]),
CLKDEV_DEV_ID("e0180000.sti", &gclk_clks[GCLK_STI_SCLK]),
};
void __init emev2_clock_init(void)
{
int k, ret = 0;
static int is_setup;
/* yuck, this is ugly as hell, but the non-smp case of clocks
* code is now designed to rely on ioremap() instead of static
* entity maps. in the case of smp we need access to the SMU
* register earlier than ioremap() is actually working without
* any static maps. to enable SMP in ugly but with dynamic
* mappings we have to call emev2_clock_init() from different
* places depending on UP and SMP...
*/
if (is_setup++)
return;
smu_base = ioremap(EMEV2_SMU_BASE, PAGE_SIZE);
BUG_ON(!smu_base);
/* setup STI timer to run on 37.768 kHz and deassert reset */
emev2_smu_write(0, STI_CLKSEL);
emev2_smu_write(1, STI_RSTCTRL);
/* deassert reset for UART0->UART3 */
emev2_smu_write(2, USIAU0_RSTCTRL);
emev2_smu_write(2, USIBU1_RSTCTRL);
emev2_smu_write(2, USIBU2_RSTCTRL);
emev2_smu_write(2, USIBU3_RSTCTRL);
for (k = 0; !ret && (k < ARRAY_SIZE(main_clks)); k++)
ret = clk_register(main_clks[k]);
if (!ret)
ret = emev2_sclkdiv_register(sclkdiv_clks, SCLKDIV_NR);
if (!ret)
ret = emev2_gclk_register(gclk_clks, GCLK_NR);
clkdev_add_table(lookups, ARRAY_SIZE(lookups));
if (!ret)
shmobile_clk_init();
else
panic("failed to setup emev2 clocks\n");
}
