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clk: make ICST driver handle the VCO registers
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It turns out that all platforms using the ICST VCO are really
just touching two registers, and in the same way as well: one
register with the VCO configuration as such, and one lock register
that makes it possible to write to the VCO.

Factor this register read/write into the ICST driver so we can
reuse it in the IM-PD1 driver.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Mike Turquette <mturquette@linaro.org>
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Linus Walleij authored and Mike Turquette committed Nov 21, 2012
1 parent 401301c commit 7a9ad67
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Showing 4 changed files with 81 additions and 95 deletions.
60 changes: 51 additions & 9 deletions drivers/clk/versatile/clk-icst.c
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Original file line number Diff line number Diff line change
Expand Up @@ -17,33 +17,74 @@
#include <linux/clkdev.h>
#include <linux/err.h>
#include <linux/clk-provider.h>
#include <linux/io.h>

#include "clk-icst.h"

/**
* struct clk_icst - ICST VCO clock wrapper
* @hw: corresponding clock hardware entry
* @vcoreg: VCO register address
* @lockreg: VCO lock register address
* @params: parameters for this ICST instance
* @rate: current rate
* @setvco: function to commit ICST settings to hardware
*/
struct clk_icst {
struct clk_hw hw;
void __iomem *vcoreg;
void __iomem *lockreg;
const struct icst_params *params;
unsigned long rate;
struct icst_vco (*getvco)(void);
void (*setvco)(struct icst_vco);
};

#define to_icst(_hw) container_of(_hw, struct clk_icst, hw)

/**
* vco_get() - get ICST VCO settings from a certain register
* @vcoreg: register containing the VCO settings
*/
static struct icst_vco vco_get(void __iomem *vcoreg)
{
u32 val;
struct icst_vco vco;

val = readl(vcoreg);
vco.v = val & 0x1ff;
vco.r = (val >> 9) & 0x7f;
vco.s = (val >> 16) & 03;
return vco;
}

/**
* vco_set() - commit changes to an ICST VCO
* @locreg: register to poke to unlock the VCO for writing
* @vcoreg: register containing the VCO settings
* @vco: ICST VCO parameters to commit
*/
static void vco_set(void __iomem *lockreg,
void __iomem *vcoreg,
struct icst_vco vco)
{
u32 val;

val = readl(vcoreg) & ~0x7ffff;
val |= vco.v | (vco.r << 9) | (vco.s << 16);

/* This magic unlocks the VCO so it can be controlled */
writel(0xa05f, lockreg);
writel(val, vcoreg);
/* This locks the VCO again */
writel(0, lockreg);
}


static unsigned long icst_recalc_rate(struct clk_hw *hw,
unsigned long parent_rate)
{
struct clk_icst *icst = to_icst(hw);
struct icst_vco vco;

vco = icst->getvco();
vco = vco_get(icst->vcoreg);
icst->rate = icst_hz(icst->params, vco);
return icst->rate;
}
Expand All @@ -66,7 +107,7 @@ static int icst_set_rate(struct clk_hw *hw, unsigned long rate,

vco = icst_hz_to_vco(icst->params, rate);
icst->rate = icst_hz(icst->params, vco);
icst->setvco(vco);
vco_set(icst->vcoreg, icst->lockreg, vco);
return 0;
}

Expand All @@ -76,8 +117,9 @@ static const struct clk_ops icst_ops = {
.set_rate = icst_set_rate,
};

struct clk * __init icst_clk_register(struct device *dev,
const struct clk_icst_desc *desc)
struct clk *icst_clk_register(struct device *dev,
const struct clk_icst_desc *desc,
void __iomem *base)
{
struct clk *clk;
struct clk_icst *icst;
Expand All @@ -95,8 +137,8 @@ struct clk * __init icst_clk_register(struct device *dev,
init.num_parents = 0;
icst->hw.init = &init;
icst->params = desc->params;
icst->getvco = desc->getvco;
icst->setvco = desc->setvco;
icst->vcoreg = base + desc->vco_offset;
icst->lockreg = base + desc->lock_offset;

clk = clk_register(dev, &icst->hw);
if (IS_ERR(clk))
Expand Down
14 changes: 11 additions & 3 deletions drivers/clk/versatile/clk-icst.h
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Original file line number Diff line number Diff line change
@@ -1,10 +1,18 @@
#include <asm/hardware/icst.h>

/**
* struct clk_icst_desc - descriptor for the ICST VCO
* @params: ICST parameters
* @vco_offset: offset to the ICST VCO from the provided memory base
* @lock_offset: offset to the ICST VCO locking register from the provided
* memory base
*/
struct clk_icst_desc {
const struct icst_params *params;
struct icst_vco (*getvco)(void);
void (*setvco)(struct icst_vco);
u32 vco_offset;
u32 lock_offset;
};

struct clk *icst_clk_register(struct device *dev,
const struct clk_icst_desc *desc);
const struct clk_icst_desc *desc,
void __iomem *base);
45 changes: 5 additions & 40 deletions drivers/clk/versatile/clk-integrator.c
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Original file line number Diff line number Diff line change
Expand Up @@ -10,7 +10,7 @@
#include <linux/clk.h>
#include <linux/clkdev.h>
#include <linux/err.h>
#include <linux/io.h>
#include <linux/platform_data/clk-integrator.h>

#include <mach/hardware.h>
#include <mach/platform.h>
Expand All @@ -22,42 +22,6 @@
* Inspired by portions of:
* plat-versatile/clock.c and plat-versatile/include/plat/clock.h
*/
#define CM_LOCK (__io_address(INTEGRATOR_HDR_BASE)+INTEGRATOR_HDR_LOCK_OFFSET)
#define CM_AUXOSC (__io_address(INTEGRATOR_HDR_BASE)+0x1c)

/**
* cp_auxvco_get() - get ICST VCO settings for the Integrator/CP
* @vco: ICST VCO parameters to update with hardware status
*/
static struct icst_vco cp_auxvco_get(void)
{
u32 val;
struct icst_vco vco;

val = readl(CM_AUXOSC);
vco.v = val & 0x1ff;
vco.r = (val >> 9) & 0x7f;
vco.s = (val >> 16) & 03;
return vco;
}

/**
* cp_auxvco_set() - commit changes to Integrator/CP ICST VCO
* @vco: ICST VCO parameters to commit
*/
static void cp_auxvco_set(struct icst_vco vco)
{
u32 val;

val = readl(CM_AUXOSC) & ~0x7ffff;
val |= vco.v | (vco.r << 9) | (vco.s << 16);

/* This magic unlocks the CM VCO so it can be controlled */
writel(0xa05f, CM_LOCK);
writel(val, CM_AUXOSC);
/* This locks the CM again */
writel(0, CM_LOCK);
}

static const struct icst_params cp_auxvco_params = {
.ref = 24000000,
Expand All @@ -73,8 +37,8 @@ static const struct icst_params cp_auxvco_params = {

static const struct clk_icst_desc __initdata cp_icst_desc = {
.params = &cp_auxvco_params,
.getvco = cp_auxvco_get,
.setvco = cp_auxvco_set,
.vco_offset = 0x1c,
.lock_offset = INTEGRATOR_HDR_LOCK_OFFSET,
};

/*
Expand Down Expand Up @@ -114,6 +78,7 @@ void __init integrator_clk_init(bool is_cp)
clk_register_clkdev(clk, NULL, "sp804");

/* ICST VCO clock used on the Integrator/CP CLCD */
clk = icst_clk_register(NULL, &cp_icst_desc);
clk = icst_clk_register(NULL, &cp_icst_desc,
__io_address(INTEGRATOR_HDR_BASE));
clk_register_clkdev(clk, NULL, "clcd");
}
57 changes: 14 additions & 43 deletions drivers/clk/versatile/clk-realview.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -21,38 +21,6 @@
* Implementation of the ARM RealView clock trees.
*/

static void __iomem *sys_lock;
static void __iomem *sys_vcoreg;

/**
* realview_oscvco_get() - get ICST OSC settings for the RealView
*/
static struct icst_vco realview_oscvco_get(void)
{
u32 val;
struct icst_vco vco;

val = readl(sys_vcoreg);
vco.v = val & 0x1ff;
vco.r = (val >> 9) & 0x7f;
vco.s = (val >> 16) & 03;
return vco;
}

static void realview_oscvco_set(struct icst_vco vco)
{
u32 val;

val = readl(sys_vcoreg) & ~0x7ffff;
val |= vco.v | (vco.r << 9) | (vco.s << 16);

/* This magic unlocks the CM VCO so it can be controlled */
writel(0xa05f, sys_lock);
writel(val, sys_vcoreg);
/* This locks the CM again */
writel(0, sys_lock);
}

static const struct icst_params realview_oscvco_params = {
.ref = 24000000,
.vco_max = ICST307_VCO_MAX,
Expand All @@ -65,10 +33,16 @@ static const struct icst_params realview_oscvco_params = {
.idx2s = icst307_idx2s,
};

static const struct clk_icst_desc __initdata realview_icst_desc = {
static const struct clk_icst_desc __initdata realview_osc0_desc = {
.params = &realview_oscvco_params,
.getvco = realview_oscvco_get,
.setvco = realview_oscvco_set,
.vco_offset = REALVIEW_SYS_OSC0_OFFSET,
.lock_offset = REALVIEW_SYS_LOCK_OFFSET,
};

static const struct clk_icst_desc __initdata realview_osc4_desc = {
.params = &realview_oscvco_params,
.vco_offset = REALVIEW_SYS_OSC4_OFFSET,
.lock_offset = REALVIEW_SYS_LOCK_OFFSET,
};

/*
Expand All @@ -78,13 +52,6 @@ void __init realview_clk_init(void __iomem *sysbase, bool is_pb1176)
{
struct clk *clk;

sys_lock = sysbase + REALVIEW_SYS_LOCK_OFFSET;
if (is_pb1176)
sys_vcoreg = sysbase + REALVIEW_SYS_OSC0_OFFSET;
else
sys_vcoreg = sysbase + REALVIEW_SYS_OSC4_OFFSET;


/* APB clock dummy */
clk = clk_register_fixed_rate(NULL, "apb_pclk", NULL, CLK_IS_ROOT, 0);
clk_register_clkdev(clk, "apb_pclk", NULL);
Expand Down Expand Up @@ -116,7 +83,11 @@ void __init realview_clk_init(void __iomem *sysbase, bool is_pb1176)
clk_register_clkdev(clk, NULL, "sp804");

/* ICST VCO clock */
clk = icst_clk_register(NULL, &realview_icst_desc);
if (is_pb1176)
clk = icst_clk_register(NULL, &realview_osc0_desc, sysbase);
else
clk = icst_clk_register(NULL, &realview_osc4_desc, sysbase);

clk_register_clkdev(clk, NULL, "dev:clcd");
clk_register_clkdev(clk, NULL, "issp:clcd");
}

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