iv/linux
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity
d4945ab647
linux/drivers/clk/mvebu/kirkwood.c
Mike Turquette 105299381d cpufreq: kirkwood: use the powersave multiplexer 
The powersave clock acts like a multiplexer for the cpu, selecting
either the clock signal derived from the cpu pll or from the ddr clock.
This patch changes powersave from a gate clock to a mux clock to better
reflect this behavior.

This is a cleaner approach whereby the frequency of the cpu always
matches the rate of powersave_clk. The cpufreq driver for the kirkwood
platform no longer must parse this behavior out of various calls to
clk_enable and clk_disable, but can instead simply select the parent cpu
it wants when changing rate. Likewise when requesting the cpu rate we
need only query powersave_clk's rate through the usual call to
clk_get_rate.

The new clock data and corresponding changes to the cpufreq driver are
combined into this single commit to avoid a git bisect issue where this
cpufreq driver fails to work properly between the commit that updates
the kirkwood clock driver and the commit that changes how the cpufreq
driver uses that clock.

Cc: Tomeu Vizoso <tomeu.vizoso@collabora.com>
Cc: Rafael J. Wysocki <rjw@rjwysocki.net>
Tested-by: Andrew Lunn <andrew@lunn.ch>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Mike Turquette <mturquette@linaro.org>
2014-09-02 15:02:54 -07:00

344 lines
8.1 KiB
C
Raw Blame History

/*
* Marvell Kirkwood SoC clocks
*
* Copyright (C) 2012 Marvell
*
* Gregory CLEMENT <gregory.clement@free-electrons.com>
* Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com>
* Andrew Lunn <andrew@lunn.ch>
*
* This file is licensed under the terms of the GNU General Public
* License version 2. This program is licensed "as is" without any
* warranty of any kind, whether express or implied.
*/
#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/clk-provider.h>
#include <linux/io.h>
#include <linux/of.h>
#include <linux/of_address.h>
#include "common.h"
/*
* Core Clocks
*
* Kirkwood PLL sample-at-reset configuration
* (6180 has different SAR layout than other Kirkwood SoCs)
*
* SAR0[4:3,22,1] : CPU frequency (6281,6292,6282)
* 4 = 600 MHz
* 6 = 800 MHz
* 7 = 1000 MHz
* 9 = 1200 MHz
* 12 = 1500 MHz
* 13 = 1600 MHz
* 14 = 1800 MHz
* 15 = 2000 MHz
* others reserved.
*
* SAR0[19,10:9] : CPU to L2 Clock divider ratio (6281,6292,6282)
* 1 = (1/2) * CPU
* 3 = (1/3) * CPU
* 5 = (1/4) * CPU
* others reserved.
*
* SAR0[8:5] : CPU to DDR DRAM Clock divider ratio (6281,6292,6282)
* 2 = (1/2) * CPU
* 4 = (1/3) * CPU
* 6 = (1/4) * CPU
* 7 = (2/9) * CPU
* 8 = (1/5) * CPU
* 9 = (1/6) * CPU
* others reserved.
*
* SAR0[4:2] : Kirkwood 6180 cpu/l2/ddr clock configuration (6180 only)
* 5 = [CPU = 600 MHz, L2 = (1/2) * CPU, DDR = 200 MHz = (1/3) * CPU]
* 6 = [CPU = 800 MHz, L2 = (1/2) * CPU, DDR = 200 MHz = (1/4) * CPU]
* 7 = [CPU = 1000 MHz, L2 = (1/2) * CPU, DDR = 200 MHz = (1/5) * CPU]
* others reserved.
*
* SAR0[21] : TCLK frequency
* 0 = 200 MHz
* 1 = 166 MHz
* others reserved.
*/
#define SAR_KIRKWOOD_CPU_FREQ(x) \
(((x & (1 << 1)) >> 1) | \
((x & (1 << 22)) >> 21) | \
((x & (3 << 3)) >> 1))
#define SAR_KIRKWOOD_L2_RATIO(x) \
(((x & (3 << 9)) >> 9) | \
(((x & (1 << 19)) >> 17)))
#define SAR_KIRKWOOD_DDR_RATIO 5
#define SAR_KIRKWOOD_DDR_RATIO_MASK 0xf
#define SAR_MV88F6180_CLK 2
#define SAR_MV88F6180_CLK_MASK 0x7
#define SAR_KIRKWOOD_TCLK_FREQ 21
#define SAR_KIRKWOOD_TCLK_FREQ_MASK 0x1
enum { KIRKWOOD_CPU_TO_L2, KIRKWOOD_CPU_TO_DDR };
static const struct coreclk_ratio kirkwood_coreclk_ratios[] __initconst = {
{ .id = KIRKWOOD_CPU_TO_L2, .name = "l2clk", },
{ .id = KIRKWOOD_CPU_TO_DDR, .name = "ddrclk", }
};
static u32 __init kirkwood_get_tclk_freq(void __iomem *sar)
{
u32 opt = (readl(sar) >> SAR_KIRKWOOD_TCLK_FREQ) &
SAR_KIRKWOOD_TCLK_FREQ_MASK;
return (opt) ? 166666667 : 200000000;
}
static const u32 kirkwood_cpu_freqs[] __initconst = {
0, 0, 0, 0,
600000000,
0,
800000000,
1000000000,
0,
1200000000,
0, 0,
1500000000,
1600000000,
1800000000,
2000000000
};
static u32 __init kirkwood_get_cpu_freq(void __iomem *sar)
{
u32 opt = SAR_KIRKWOOD_CPU_FREQ(readl(sar));
return kirkwood_cpu_freqs[opt];
}
static const int kirkwood_cpu_l2_ratios[8][2] __initconst = {
{ 0, 1 }, { 1, 2 }, { 0, 1 }, { 1, 3 },
{ 0, 1 }, { 1, 4 }, { 0, 1 }, { 0, 1 }
};
static const int kirkwood_cpu_ddr_ratios[16][2] __initconst = {
{ 0, 1 }, { 0, 1 }, { 1, 2 }, { 0, 1 },
{ 1, 3 }, { 0, 1 }, { 1, 4 }, { 2, 9 },
{ 1, 5 }, { 1, 6 }, { 0, 1 }, { 0, 1 },
{ 0, 1 }, { 0, 1 }, { 0, 1 }, { 0, 1 }
};
static void __init kirkwood_get_clk_ratio(
void __iomem *sar, int id, int *mult, int *div)
{
switch (id) {
case KIRKWOOD_CPU_TO_L2:
{
u32 opt = SAR_KIRKWOOD_L2_RATIO(readl(sar));
*mult = kirkwood_cpu_l2_ratios[opt][0];
*div = kirkwood_cpu_l2_ratios[opt][1];
break;
}
case KIRKWOOD_CPU_TO_DDR:
{
u32 opt = (readl(sar) >> SAR_KIRKWOOD_DDR_RATIO) &
SAR_KIRKWOOD_DDR_RATIO_MASK;
*mult = kirkwood_cpu_ddr_ratios[opt][0];
*div = kirkwood_cpu_ddr_ratios[opt][1];
break;
}
}
}
static const u32 mv88f6180_cpu_freqs[] __initconst = {
0, 0, 0, 0, 0,
600000000,
800000000,
1000000000
};
static u32 __init mv88f6180_get_cpu_freq(void __iomem *sar)
{
u32 opt = (readl(sar) >> SAR_MV88F6180_CLK) & SAR_MV88F6180_CLK_MASK;
return mv88f6180_cpu_freqs[opt];
}
static const int mv88f6180_cpu_ddr_ratios[8][2] __initconst = {
{ 0, 1 }, { 0, 1 }, { 0, 1 }, { 0, 1 },
{ 0, 1 }, { 1, 3 }, { 1, 4 }, { 1, 5 }
};
static void __init mv88f6180_get_clk_ratio(
void __iomem *sar, int id, int *mult, int *div)
{
switch (id) {
case KIRKWOOD_CPU_TO_L2:
{
/* mv88f6180 has a fixed 1:2 CPU-to-L2 ratio */
*mult = 1;
*div = 2;
break;
}
case KIRKWOOD_CPU_TO_DDR:
{
u32 opt = (readl(sar) >> SAR_MV88F6180_CLK) &
SAR_MV88F6180_CLK_MASK;
*mult = mv88f6180_cpu_ddr_ratios[opt][0];
*div = mv88f6180_cpu_ddr_ratios[opt][1];
break;
}
}
}
static const struct coreclk_soc_desc kirkwood_coreclks = {
.get_tclk_freq = kirkwood_get_tclk_freq,
.get_cpu_freq = kirkwood_get_cpu_freq,
.get_clk_ratio = kirkwood_get_clk_ratio,
.ratios = kirkwood_coreclk_ratios,
.num_ratios = ARRAY_SIZE(kirkwood_coreclk_ratios),
};
static const struct coreclk_soc_desc mv88f6180_coreclks = {
.get_tclk_freq = kirkwood_get_tclk_freq,
.get_cpu_freq = mv88f6180_get_cpu_freq,
.get_clk_ratio = mv88f6180_get_clk_ratio,
.ratios = kirkwood_coreclk_ratios,
.num_ratios = ARRAY_SIZE(kirkwood_coreclk_ratios),
};
/*
* Clock Gating Control
*/
static const struct clk_gating_soc_desc kirkwood_gating_desc[] __initconst = {
{ "ge0", NULL, 0, 0 },
{ "pex0", NULL, 2, 0 },
{ "usb0", NULL, 3, 0 },
{ "sdio", NULL, 4, 0 },
{ "tsu", NULL, 5, 0 },
{ "runit", NULL, 7, 0 },
{ "xor0", NULL, 8, 0 },
{ "audio", NULL, 9, 0 },
{ "sata0", NULL, 14, 0 },
{ "sata1", NULL, 15, 0 },
{ "xor1", NULL, 16, 0 },
{ "crypto", NULL, 17, 0 },
{ "pex1", NULL, 18, 0 },
{ "ge1", NULL, 19, 0 },
{ "tdm", NULL, 20, 0 },
{ }
};
/*
* Clock Muxing Control
*/
struct clk_muxing_soc_desc {
const char *name;
const char **parents;
int num_parents;
int shift;
int width;
unsigned long flags;
};
struct clk_muxing_ctrl {
spinlock_t *lock;
struct clk **muxes;
int num_muxes;
};
static const char *powersave_parents[] = {
"cpuclk",
"ddrclk",
};
static const struct clk_muxing_soc_desc kirkwood_mux_desc[] __initconst = {
{ "powersave", powersave_parents, ARRAY_SIZE(powersave_parents),
11, 1, 0 },
};
#define to_clk_mux(_hw) container_of(_hw, struct clk_mux, hw)
static struct clk *clk_muxing_get_src(
struct of_phandle_args *clkspec, void *data)
{
struct clk_muxing_ctrl *ctrl = (struct clk_muxing_ctrl *)data;
int n;
if (clkspec->args_count < 1)
return ERR_PTR(-EINVAL);
for (n = 0; n < ctrl->num_muxes; n++) {
struct clk_mux *mux =
to_clk_mux(__clk_get_hw(ctrl->muxes[n]));
if (clkspec->args[0] == mux->shift)
return ctrl->muxes[n];
}
return ERR_PTR(-ENODEV);
}
static void __init kirkwood_clk_muxing_setup(struct device_node *np,
const struct clk_muxing_soc_desc *desc)
{
struct clk_muxing_ctrl *ctrl;
void __iomem *base;
int n;
base = of_iomap(np, 0);
if (WARN_ON(!base))
return;
ctrl = kzalloc(sizeof(*ctrl), GFP_KERNEL);
if (WARN_ON(!ctrl))
goto ctrl_out;
/* lock must already be initialized */
ctrl->lock = &ctrl_gating_lock;
/* Count, allocate, and register clock muxes */
for (n = 0; desc[n].name;)
n++;
ctrl->num_muxes = n;
ctrl->muxes = kcalloc(ctrl->num_muxes, sizeof(struct clk *),
GFP_KERNEL);
if (WARN_ON(!ctrl->muxes))
goto muxes_out;
for (n = 0; n < ctrl->num_muxes; n++) {
ctrl->muxes[n] = clk_register_mux(NULL, desc[n].name,
desc[n].parents, desc[n].num_parents,
desc[n].flags, base, desc[n].shift,
desc[n].width, desc[n].flags, ctrl->lock);
WARN_ON(IS_ERR(ctrl->muxes[n]));
}
of_clk_add_provider(np, clk_muxing_get_src, ctrl);
return;
muxes_out:
kfree(ctrl);
ctrl_out:
iounmap(base);
}
static void __init kirkwood_clk_init(struct device_node *np)
{
struct device_node *cgnp =
of_find_compatible_node(NULL, NULL, "marvell,kirkwood-gating-clock");
if (of_device_is_compatible(np, "marvell,mv88f6180-core-clock"))
mvebu_coreclk_setup(np, &mv88f6180_coreclks);
else
mvebu_coreclk_setup(np, &kirkwood_coreclks);
if (cgnp) {
mvebu_clk_gating_setup(cgnp, kirkwood_gating_desc);
kirkwood_clk_muxing_setup(cgnp, kirkwood_mux_desc);
}
}
CLK_OF_DECLARE(kirkwood_clk, "marvell,kirkwood-core-clock",
kirkwood_clk_init);
CLK_OF_DECLARE(mv88f6180_clk, "marvell,mv88f6180-core-clock",
kirkwood_clk_init);
Reference in New Issue View Git Blame Copy Permalink