Commit 1929cb34 authored by dmitry pervushin's avatar dmitry pervushin Committed by Paul Mundt

sh: SH7722 clock framework support.

This adds support for the SH7722 (MobileR) to the clock framework.
Signed-off-by: default avatardmitry pervushin <dimka@nomadgs.com>
Signed-off-by: default avatarPaul Mundt <lethal@linux-sh.org>
parent 34a780a0
Clock framework on SuperH architecture
The framework on SH extends existing API by the function clk_set_rate_ex,
which prototype is as follows:
clk_set_rate_ex (struct clk *clk, unsigned long rate, int algo_id)
The algo_id parameter is used to specify algorithm used to recalculate clocks,
adjanced to clock, specified as first argument. It is assumed that algo_id==0
means no changes to adjanced clock
Internally, the clk_set_rate_ex forwards request to clk->ops->set_rate method,
if it is present in ops structure. The method should set the clock rate and adjust
all needed clocks according to the passed algo_id.
Exact values for algo_id are machine-dependend. For the sh7722, the following
values are defined:
NO_CHANGE = 0,
IUS_N1_N1, /* I:U = N:1, U:Sh = N:1 */
IUS_322, /* I:U:Sh = 3:2:2 */
IUS_522, /* I:U:Sh = 5:2:2 */
IUS_N11, /* I:U:Sh = N:1:1 */
SB_N1, /* Sh:B = N:1 */
SB3_N1, /* Sh:B3 = N:1 */
SB3_32, /* Sh:B3 = 3:2 */
SB3_43, /* Sh:B3 = 4:3 */
SB3_54, /* Sh:B3 = 5:4 */
BP_N1, /* B:P = N:1 */
IP_N1 /* I:P = N:1 */
Each of these constants means relation between clocks that can be set via the FRQCR
register
......@@ -98,13 +98,14 @@ int __clk_enable(struct clk *clk)
if (clk->ops && clk->ops->init)
clk->ops->init(clk);
kref_get(&clk->kref);
if (clk->flags & CLK_ALWAYS_ENABLED)
return 0;
if (likely(clk->ops && clk->ops->enable))
clk->ops->enable(clk);
kref_get(&clk->kref);
return 0;
}
......@@ -127,10 +128,15 @@ static void clk_kref_release(struct kref *kref)
void __clk_disable(struct clk *clk)
{
int count = kref_put(&clk->kref, clk_kref_release);
if (clk->flags & CLK_ALWAYS_ENABLED)
return;
kref_put(&clk->kref, clk_kref_release);
if (!count) { /* count reaches zero, disable the clock */
if (likely(clk->ops && clk->ops->disable))
clk->ops->disable(clk);
}
}
void clk_disable(struct clk *clk)
......@@ -151,6 +157,15 @@ int clk_register(struct clk *clk)
mutex_unlock(&clock_list_sem);
if (clk->flags & CLK_ALWAYS_ENABLED) {
pr_debug( "Clock '%s' is ALWAYS_ENABLED\n", clk->name);
if (clk->ops && clk->ops->init)
clk->ops->init(clk);
if (clk->ops && clk->ops->enable)
clk->ops->enable(clk);
pr_debug( "Enabled.");
}
return 0;
}
......@@ -167,6 +182,11 @@ inline unsigned long clk_get_rate(struct clk *clk)
}
int clk_set_rate(struct clk *clk, unsigned long rate)
{
return clk_set_rate_ex(clk, rate, 0);
}
int clk_set_rate_ex(struct clk *clk, unsigned long rate, int algo_id)
{
int ret = -EOPNOTSUPP;
......@@ -174,7 +194,7 @@ int clk_set_rate(struct clk *clk, unsigned long rate)
unsigned long flags;
spin_lock_irqsave(&clock_lock, flags);
ret = clk->ops->set_rate(clk, rate);
ret = clk->ops->set_rate(clk, rate, algo_id);
spin_unlock_irqrestore(&clock_lock, flags);
}
......@@ -256,7 +276,6 @@ int __init clk_init(void)
arch_init_clk_ops(&clk->ops, i);
ret |= clk_register(clk);
clk_enable(clk);
}
/* Kick the child clocks.. */
......@@ -298,3 +317,4 @@ EXPORT_SYMBOL_GPL(__clk_disable);
EXPORT_SYMBOL_GPL(clk_get_rate);
EXPORT_SYMBOL_GPL(clk_set_rate);
EXPORT_SYMBOL_GPL(clk_recalc_rate);
EXPORT_SYMBOL_GPL(clk_set_rate_ex);
......@@ -82,7 +82,8 @@ static void shoc_clk_init(struct clk *clk)
for (i = 0; i < ARRAY_SIZE(frqcr3_divisors); i++) {
int divisor = frqcr3_divisors[i];
if (clk->ops->set_rate(clk, clk->parent->rate / divisor) == 0)
if (clk->ops->set_rate(clk, clk->parent->rate /
divisor, 0) == 0)
break;
}
......
......@@ -16,6 +16,6 @@ clock-$(CONFIG_CPU_SUBTYPE_SH7770) := clock-sh7770.o
clock-$(CONFIG_CPU_SUBTYPE_SH7780) := clock-sh7780.o
clock-$(CONFIG_CPU_SUBTYPE_SH7785) := clock-sh7785.o
clock-$(CONFIG_CPU_SUBTYPE_SH7343) := clock-sh7343.o
clock-$(CONFIG_CPU_SUBTYPE_SH7722) := clock-sh7343.o
clock-$(CONFIG_CPU_SUBTYPE_SH7722) := clock-sh7722.o
obj-y += $(clock-y)
/*
* arch/sh/kernel/cpu/sh4a/clock-sh7722.c
*
* SH7722 support for the clock framework
*
* Copyright (c) 2006-2007 Nomad Global Solutions Inc
* Based on code for sh7343 by Paul Mundt
*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*/
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/io.h>
#include <linux/errno.h>
#include <asm/clock.h>
#include <asm/freq.h>
#define SH7722_PLL_FREQ (32000000/8)
#define N (-1)
#define NM (-2)
#define ROUND_NEAREST 0
#define ROUND_DOWN -1
#define ROUND_UP +1
static int adjust_algos[][3] = {
{}, /* NO_CHANGE */
{ NM, N, 1 }, /* N:1, N:1 */
{ 3, 2, 2 }, /* 3:2:2 */
{ 5, 2, 2 }, /* 5:2:2 */
{ N, 1, 1 }, /* N:1:1 */
{ N, 1 }, /* N:1 */
{ N, 1 }, /* N:1 */
{ 3, 2 },
{ 4, 3 },
{ 5, 4 },
{ N, 1 }
};
static unsigned long adjust_pair_of_clocks(unsigned long r1, unsigned long r2,
int m1, int m2, int round_flag)
{
unsigned long rem, div;
int the_one = 0;
pr_debug( "Actual values: r1 = %ld\n", r1);
pr_debug( "...............r2 = %ld\n", r2);
if (m1 == m2) {
r2 = r1;
pr_debug( "setting equal rates: r2 now %ld\n", r2);
} else if ((m2 == N && m1 == 1) ||
(m2 == NM && m1 == N)) { /* N:1 or NM:N */
pr_debug( "Setting rates as 1:N (N:N*M)\n");
rem = r2 % r1;
pr_debug( "...remainder = %ld\n", rem);
if (rem) {
div = r2 / r1;
pr_debug( "...div = %ld\n", div);
switch (round_flag) {
case ROUND_NEAREST:
the_one = rem >= r1/2 ? 1 : 0; break;
case ROUND_UP:
the_one = 1; break;
case ROUND_DOWN:
the_one = 0; break;
}
r2 = r1 * (div + the_one);
pr_debug( "...setting r2 to %ld\n", r2);
}
} else if ((m2 == 1 && m1 == N) ||
(m2 == N && m1 == NM)) { /* 1:N or N:NM */
pr_debug( "Setting rates as N:1 (N*M:N)\n");
rem = r1 % r2;
pr_debug( "...remainder = %ld\n", rem);
if (rem) {
div = r1 / r2;
pr_debug( "...div = %ld\n", div);
switch (round_flag) {
case ROUND_NEAREST:
the_one = rem > r2/2 ? 1 : 0; break;
case ROUND_UP:
the_one = 0; break;
case ROUND_DOWN:
the_one = 1; break;
}
r2 = r1 / (div + the_one);
pr_debug( "...setting r2 to %ld\n", r2);
}
} else { /* value:value */
pr_debug( "Setting rates as %d:%d\n", m1, m2);
div = r1 / m1;
r2 = div * m2;
pr_debug( "...div = %ld\n", div);
pr_debug( "...setting r2 to %ld\n", r2);
}
return r2;
}
static void adjust_clocks(int originate, int *l, unsigned long v[],
int n_in_line)
{
int x;
pr_debug( "Go down from %d...\n", originate);
/* go up recalculation clocks */
for (x = originate; x>0; x -- )
v[x-1] = adjust_pair_of_clocks(v[x], v[x-1],
l[x], l[x-1],
ROUND_UP);
pr_debug( "Go up from %d...\n", originate);
/* go down recalculation clocks */
for (x = originate; x<n_in_line - 1; x ++ )
v[x+1] = adjust_pair_of_clocks(v[x], v[x+1],
l[x], l[x+1],
ROUND_UP);
}
/*
* SH7722 uses a common set of multipliers and divisors, so this
* is quite simple..
*/
/*
* Instead of having two separate multipliers/divisors set, like this:
*
* static int multipliers[] = { 1, 2, 1, 2, 1, 1, 1, 1, 1, 1, 1, 1, 1 };
* static int divisors[] = { 1, 3, 2, 5, 3, 4, 5, 6, 8, 10, 12, 16, 20 };
*
* I created the divisors2 array, which is used to calculate rate like
* rate = parent * 2 / divisors2[ divisor ];
*/
static int divisors2[] = { 2, 3, 4, 5, 6, 8, 10, 12, 16, 20, 24, 32, 40 };
static void master_clk_init(struct clk *clk)
{
clk_set_rate(clk, clk_get_rate(clk));
}
static void master_clk_recalc(struct clk *clk)
{
unsigned long frqcr = ctrl_inl(FRQCR);
clk->rate = CONFIG_SH_PCLK_FREQ * (1 + (frqcr >> 24 & 0xF));
}
static int master_clk_setrate(struct clk *clk, unsigned long rate, int id)
{
int div = rate / SH7722_PLL_FREQ;
int master_divs[] = { 2, 3, 4, 6, 8, 16 };
int index;
unsigned long frqcr;
if (rate < SH7722_PLL_FREQ * 2)
return -EINVAL;
for (index = 1; index < ARRAY_SIZE(master_divs); index++)
if (div >= master_divs[index - 1] && div < master_divs[index])
break;
if (index >= ARRAY_SIZE(master_divs))
index = ARRAY_SIZE(master_divs);
div = master_divs[index - 1];
frqcr = ctrl_inl(FRQCR);
frqcr &= ~(0xF << 24);
frqcr |= ( (div-1) << 24);
ctrl_outl(frqcr, FRQCR);
return 0;
}
static struct clk_ops sh7722_master_clk_ops = {
.init = master_clk_init,
.recalc = master_clk_recalc,
.set_rate = master_clk_setrate,
};
struct frqcr_context {
unsigned mask;
unsigned shift;
};
struct frqcr_context sh7722_get_clk_context(const char *name)
{
struct frqcr_context ctx = { 0, };
if (!strcmp(name, "peripheral_clk")) {
ctx.shift = 0;
ctx.mask = 0xF;
} else if (!strcmp(name, "sdram_clk")) {
ctx.shift = 4;
ctx.mask = 0xF;
} else if (!strcmp(name, "bus_clk")) {
ctx.shift = 8;
ctx.mask = 0xF;
} else if (!strcmp(name, "sh_clk")) {
ctx.shift = 12;
ctx.mask = 0xF;
} else if (!strcmp(name, "umem_clk")) {
ctx.shift = 16;
ctx.mask = 0xF;
} else if (!strcmp(name, "cpu_clk")) {
ctx.shift = 20;
ctx.mask = 7;
}
return ctx;
}
/**
* sh7722_find_divisors - find divisor for setting rate
*
* All sh7722 clocks use the same set of multipliers/divisors. This function
* chooses correct divisor to set the rate of clock with parent clock that
* generates frequency of 'parent_rate'
*
* @parent_rate: rate of parent clock
* @rate: requested rate to be set
*/
static int sh7722_find_divisors(unsigned long parent_rate, unsigned rate)
{
unsigned div2 = parent_rate * 2 / rate;
int index;
if (rate > parent_rate)
return -EINVAL;
for (index = 1; index < ARRAY_SIZE(divisors2); index++) {
if (div2 > divisors2[index] && div2 <= divisors2[index])
break;
}
if (index >= ARRAY_SIZE(divisors2))
index = ARRAY_SIZE(divisors2) - 1;
return divisors2[index];
}
static void sh7722_frqcr_recalc(struct clk *clk)
{
struct frqcr_context ctx = sh7722_get_clk_context(clk->name);
unsigned long frqcr = ctrl_inl(FRQCR);
int index;
index = (frqcr >> ctx.shift) & ctx.mask;
clk->rate = clk->parent->rate * 2 / divisors2[index];
}
static int sh7722_frqcr_set_rate(struct clk *clk, unsigned long rate,
int algo_id)
{
struct frqcr_context ctx = sh7722_get_clk_context(clk->name);
unsigned long parent_rate = clk->parent->rate;
int div;
unsigned long frqcr;
int err = 0;
/* pretty invalid */
if (parent_rate < rate)
return -EINVAL;
/* look for multiplier/divisor pair */
div = sh7722_find_divisors(parent_rate, rate);
if (div<0)
return div;
/* calculate new value of clock rate */
clk->rate = parent_rate * 2 / div;
frqcr = ctrl_inl(FRQCR);
/* FIXME: adjust as algo_id specifies */
if (algo_id != NO_CHANGE) {
int originator;
char *algo_group_1[] = { "cpu_clk", "umem_clk", "sh_clk" };
char *algo_group_2[] = { "sh_clk", "bus_clk" };
char *algo_group_3[] = { "sh_clk", "sdram_clk" };
char *algo_group_4[] = { "bus_clk", "peripheral_clk" };
char *algo_group_5[] = { "cpu_clk", "peripheral_clk" };
char **algo_current = NULL;
/* 3 is the maximum number of clocks in relation */
struct clk *ck[3];
unsigned long values[3]; /* the same comment as above */
int part_length = -1;
int i;
/*
* all the steps below only required if adjustion was
* requested
*/
if (algo_id == IUS_N1_N1 ||
algo_id == IUS_322 ||
algo_id == IUS_522 ||
algo_id == IUS_N11) {
algo_current = algo_group_1;
part_length = 3;
}
if (algo_id == SB_N1) {
algo_current = algo_group_2;
part_length = 2;
}
if (algo_id == SB3_N1 ||
algo_id == SB3_32 ||
algo_id == SB3_43 ||
algo_id == SB3_54) {
algo_current = algo_group_3;
part_length = 2;
}
if (algo_id == BP_N1) {
algo_current = algo_group_4;
part_length = 2;
}
if (algo_id == IP_N1) {
algo_current = algo_group_5;
part_length = 2;
}
if (!algo_current)
goto incorrect_algo_id;
originator = -1;
for (i = 0; i < part_length; i ++ ) {
if (originator >= 0 && !strcmp(clk->name,
algo_current[i]))
originator = i;
ck[i] = clk_get(NULL, algo_current[i]);
values[i] = clk_get_rate(ck[i]);
}
if (originator >= 0)
adjust_clocks(originator, adjust_algos[algo_id],
values, part_length);
for (i = 0; i < part_length; i ++ ) {
struct frqcr_context part_ctx;
int part_div;
if (likely(!err)) {
part_div = sh7722_find_divisors(parent_rate,
rate);
if (part_div > 0) {
part_ctx = sh7722_get_clk_context(
ck[i]->name);
frqcr &= ~(part_ctx.mask <<
part_ctx.shift);
frqcr |= part_div << part_ctx.shift;
} else
err = part_div;
}
ck[i]->ops->recalc(ck[i]);
clk_put(ck[i]);
}
}
/* was there any error during recalculation ? If so, bail out.. */
if (unlikely(err!=0))
goto out_err;
/* clear FRQCR bits */
frqcr &= ~(ctx.mask << ctx.shift);
frqcr |= div << ctx.shift;
/* ...and perform actual change */
ctrl_outl(frqcr, FRQCR);
return 0;
incorrect_algo_id:
return -EINVAL;
out_err:
return err;
}
static struct clk_ops sh7722_frqcr_clk_ops = {
.recalc = sh7722_frqcr_recalc,
.set_rate = sh7722_frqcr_set_rate,
};
/*
* clock ops methods for SIU A/B and IrDA clock
*
*/
static int sh7722_siu_which(struct clk *clk)
{
if (!strcmp(clk->name, "siu_a_clk"))
return 0;
if (!strcmp(clk->name, "siu_b_clk"))
return 1;
if (!strcmp(clk->name, "irda_clk"))
return 2;
return -EINVAL;
}
static unsigned long sh7722_siu_regs[] = {
[0] = SCLKACR,
[1] = SCLKBCR,
[2] = IrDACLKCR,
};
static int sh7722_siu_start_stop(struct clk *clk, int enable)
{
int siu = sh7722_siu_which(clk);
unsigned long r;
if (siu < 0)
return siu;
BUG_ON(siu > 2);
r = ctrl_inl(sh7722_siu_regs[siu]);
if (enable)
ctrl_outl(r & ~(1 << 8), sh7722_siu_regs[siu]);
else
ctrl_outl(r | (1 << 8), sh7722_siu_regs[siu]);
return 0;
}
static void sh7722_siu_enable(struct clk *clk)
{
sh7722_siu_start_stop(clk, 1);
}
static void sh7722_siu_disable(struct clk *clk)
{
sh7722_siu_start_stop(clk, 0);
}
static void sh7722_video_enable(struct clk *clk)
{
unsigned long r;
r = ctrl_inl(VCLKCR);
ctrl_outl( r & ~(1<<8), VCLKCR);
}
static void sh7722_video_disable(struct clk *clk)
{
unsigned long r;
r = ctrl_inl(VCLKCR);
ctrl_outl( r | (1<<8), VCLKCR);
}
static int sh7722_video_set_rate(struct clk *clk, unsigned long rate,
int algo_id)
{
unsigned long r;
r = ctrl_inl(VCLKCR);
r &= ~0x3F;
r |= ((clk->parent->rate / rate - 1) & 0x3F);
ctrl_outl(r, VCLKCR);
return 0;
}
static void sh7722_video_recalc(struct clk *clk)
{
unsigned long r;
r = ctrl_inl(VCLKCR);
clk->rate = clk->parent->rate / ((r & 0x3F) + 1);
}
static int sh7722_siu_set_rate(struct clk *clk, unsigned long rate, int algo_id)
{
int siu = sh7722_siu_which(clk);
unsigned long r;
int div;
if (siu < 0)
return siu;
BUG_ON(siu > 2);
r = ctrl_inl(sh7722_siu_regs[siu]);
div = sh7722_find_divisors(clk->parent->rate, rate);
if (div < 0)
return div;
r = (r & ~0xF) | div;
ctrl_outl(r, sh7722_siu_regs[siu]);
return 0;
}
static void sh7722_siu_recalc(struct clk *clk)
{
int siu = sh7722_siu_which(clk);
unsigned long r;
if (siu < 0)
return /* siu */ ;
BUG_ON(siu > 1);
r = ctrl_inl(sh7722_siu_regs[siu]);
clk->rate = clk->parent->rate * 2 / divisors2[r & 0xF];
}
static struct clk_ops sh7722_siu_clk_ops = {
.recalc = sh7722_siu_recalc,
.set_rate = sh7722_siu_set_rate,
.enable = sh7722_siu_enable,
.disable = sh7722_siu_disable,
};
static struct clk_ops sh7722_video_clk_ops = {
.recalc = sh7722_video_recalc,
.set_rate = sh7722_video_set_rate,
.enable = sh7722_video_enable,
.disable = sh7722_video_disable,
};
/*
* and at last, clock definitions themselves
*/
static struct clk sh7722_umem_clock = {
.name = "umem_clk",
.ops = &sh7722_frqcr_clk_ops,
};
static struct clk sh7722_sh_clock = {
.name = "sh_clk",
.ops = &sh7722_frqcr_clk_ops,
};
static struct clk sh7722_peripheral_clock = {
.name = "peripheral_clk",
.ops = &sh7722_frqcr_clk_ops,
};
static struct clk sh7722_sdram_clock = {
.name = "sdram_clk",
.ops = &sh7722_frqcr_clk_ops,
};
/*
* these three clocks - SIU A, SIU B, IrDA - share the same clk_ops
* methods of clk_ops determine which register they should access by
* examining clk->name field
*/
static struct clk sh7722_siu_a_clock = {
.name = "siu_a_clk",
.ops = &sh7722_siu_clk_ops,
};
static struct clk sh7722_siu_b_clock = {
.name = "siu_b_clk",
.ops = &sh7722_siu_clk_ops,
};
static struct clk sh7722_irda_clock = {
.name = "irda_clk",
.ops = &sh7722_siu_clk_ops,
};
static struct clk sh7722_video_clock = {
.name = "video_clk",
.ops = &sh7722_video_clk_ops,
};
static struct clk *sh7722_clocks[] = {
&sh7722_umem_clock,
&sh7722_sh_clock,
&sh7722_peripheral_clock,
&sh7722_sdram_clock,
&sh7722_siu_a_clock,
&sh7722_siu_b_clock,
&sh7722_irda_clock,
&sh7722_video_clock,
};
/*
* init in order: master, module, bus, cpu
*/
struct clk_ops *onchip_ops[] = {
&sh7722_master_clk_ops,
&sh7722_frqcr_clk_ops,
&sh7722_frqcr_clk_ops,
&sh7722_frqcr_clk_ops,
};
void __init
arch_init_clk_ops(struct clk_ops **ops, int type)
{
BUG_ON(type < 0 || type > ARRAY_SIZE(onchip_ops));
*ops = onchip_ops[type];
}
int __init sh7722_clock_init(void)
{
struct clk *master;
int i;
master = clk_get(NULL, "master_clk");
for (i = 0; i < ARRAY_SIZE(sh7722_clocks); i++) {
pr_debug( "Registering clock '%s'\n", sh7722_clocks[i]->name);
sh7722_clocks[i]->parent = master;
clk_register(sh7722_clocks[i]);
}
clk_put(master);
return 0;
}
arch_initcall(sh7722_clock_init);
......@@ -13,7 +13,7 @@ struct clk_ops {
void (*enable)(struct clk *clk);
void (*disable)(struct clk *clk);
void (*recalc)(struct clk *clk);
int (*set_rate)(struct clk *clk, unsigned long rate);
int (*set_rate)(struct clk *clk, unsigned long rate, int algo_id);
};
struct clk {
......@@ -50,4 +50,34 @@ void clk_unregister(struct clk *);
int show_clocks(struct seq_file *m);
/* the exported API, in addition to clk_set_rate */
/**
* clk_set_rate_ex - set the clock rate for a clock source, with additional parameter
* @clk: clock source
* @rate: desired clock rate in Hz
* @algo_id: algorithm id to be passed down to ops->set_rate
*
* Returns success (0) or negative errno.
*/
int clk_set_rate_ex(struct clk *clk, unsigned long rate, int algo_id);
enum clk_sh_algo_id {
NO_CHANGE = 0,
IUS_N1_N1,
IUS_322,
IUS_522,
IUS_N11,
SB_N1,
SB3_N1,
SB3_32,
SB3_43,
SB3_54,
BP_N1,
IP_N1,
};
#endif /* __ASM_SH_CLOCK_H */
......@@ -12,6 +12,10 @@
#if defined(CONFIG_CPU_SUBTYPE_SH73180) || defined(CONFIG_CPU_SUBTYPE_SH7722)
#define FRQCR 0xa4150000
#define VCLKCR 0xa4150004
#define SCLKACR 0xa4150008
#define SCLKBCR 0xa415000c
#define IrDACLKCR 0xa4150010
#elif defined(CONFIG_CPU_SUBTYPE_SH7780)
#define FRQCR 0xffc80000
#elif defined(CONFIG_CPU_SUBTYPE_SH7785)
......
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