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Subject[PATCH v2 4/8] clk: at91: clk-sam9x60-pll: allow runtime changes for pll
Date
Allow runtime frequency changes for PLLs registered with proper flags.
This is necessary for CPU PLL on SAMA7G5 which is used by DVFS.

Signed-off-by: Claudiu Beznea <claudiu.beznea@microchip.com>
---
drivers/clk/at91/clk-sam9x60-pll.c | 102 ++++++++++++++++++++++++++++++-------
drivers/clk/at91/pmc.h | 4 +-
drivers/clk/at91/sam9x60.c | 13 +++--
drivers/clk/at91/sama7g5.c | 48 ++++++++++-------
4 files changed, 127 insertions(+), 40 deletions(-)

diff --git a/drivers/clk/at91/clk-sam9x60-pll.c b/drivers/clk/at91/clk-sam9x60-pll.c
index 78f458a7b2ef..6fe5d8530a0c 100644
--- a/drivers/clk/at91/clk-sam9x60-pll.c
+++ b/drivers/clk/at91/clk-sam9x60-pll.c
@@ -225,8 +225,51 @@ static int sam9x60_frac_pll_set_rate(struct clk_hw *hw, unsigned long rate,
unsigned long parent_rate)
{
struct sam9x60_pll_core *core = to_sam9x60_pll_core(hw);
+ struct sam9x60_frac *frac = to_sam9x60_frac(core);
+ struct regmap *regmap = core->regmap;
+ unsigned long irqflags, clkflags = clk_hw_get_flags(hw);
+ unsigned int val, cfrac, cmul;
+ long ret;
+
+ ret = sam9x60_frac_pll_compute_mul_frac(core, rate, parent_rate, true);
+ if (ret <= 0 || (clkflags & CLK_SET_RATE_GATE))
+ return ret;
+
+ spin_lock_irqsave(core->lock, irqflags);
+
+ regmap_update_bits(regmap, AT91_PMC_PLL_UPDT, AT91_PMC_PLL_UPDT_ID_MSK,
+ core->id);
+ regmap_read(regmap, AT91_PMC_PLL_CTRL1, &val);
+ cmul = (val & core->layout->mul_mask) >> core->layout->mul_shift;
+ cfrac = (val & core->layout->frac_mask) >> core->layout->frac_shift;
+
+ if (cmul == frac->mul && cfrac == frac->frac)
+ goto unlock;
+
+ regmap_write(regmap, AT91_PMC_PLL_CTRL1,
+ (frac->mul << core->layout->mul_shift) |
+ (frac->frac << core->layout->frac_shift));
+
+ regmap_update_bits(regmap, AT91_PMC_PLL_UPDT,
+ AT91_PMC_PLL_UPDT_UPDATE | AT91_PMC_PLL_UPDT_ID_MSK,
+ AT91_PMC_PLL_UPDT_UPDATE | core->id);
+
+ regmap_update_bits(regmap, AT91_PMC_PLL_CTRL0,
+ AT91_PMC_PLL_CTRL0_ENLOCK | AT91_PMC_PLL_CTRL0_ENPLL,
+ AT91_PMC_PLL_CTRL0_ENLOCK |
+ AT91_PMC_PLL_CTRL0_ENPLL);
+
+ regmap_update_bits(regmap, AT91_PMC_PLL_UPDT,
+ AT91_PMC_PLL_UPDT_UPDATE | AT91_PMC_PLL_UPDT_ID_MSK,
+ AT91_PMC_PLL_UPDT_UPDATE | core->id);

- return sam9x60_frac_pll_compute_mul_frac(core, rate, parent_rate, true);
+ while (!sam9x60_pll_ready(regmap, core->id))
+ cpu_relax();
+
+unlock:
+ spin_unlock_irqrestore(core->lock, irqflags);
+
+ return ret;
}

static const struct clk_ops sam9x60_frac_pll_ops = {
@@ -378,9 +421,39 @@ static int sam9x60_div_pll_set_rate(struct clk_hw *hw, unsigned long rate,
{
struct sam9x60_pll_core *core = to_sam9x60_pll_core(hw);
struct sam9x60_div *div = to_sam9x60_div(core);
+ struct regmap *regmap = core->regmap;
+ unsigned long irqflags, clkflags = clk_hw_get_flags(hw);
+ unsigned int val, cdiv;

div->div = DIV_ROUND_CLOSEST(parent_rate, rate) - 1;

+ if (clkflags & CLK_SET_RATE_GATE)
+ return 0;
+
+ spin_lock_irqsave(core->lock, irqflags);
+ regmap_update_bits(regmap, AT91_PMC_PLL_UPDT, AT91_PMC_PLL_UPDT_ID_MSK,
+ core->id);
+ regmap_read(regmap, AT91_PMC_PLL_CTRL0, &val);
+ cdiv = (val & core->layout->div_mask) >> core->layout->div_shift;
+
+ /* Stop if nothing changed. */
+ if (cdiv == div->div)
+ goto unlock;
+
+ regmap_update_bits(regmap, AT91_PMC_PLL_CTRL0,
+ core->layout->div_mask,
+ (div->div << core->layout->div_shift));
+
+ regmap_update_bits(regmap, AT91_PMC_PLL_UPDT,
+ AT91_PMC_PLL_UPDT_UPDATE | AT91_PMC_PLL_UPDT_ID_MSK,
+ AT91_PMC_PLL_UPDT_UPDATE | core->id);
+
+ while (!sam9x60_pll_ready(regmap, core->id))
+ cpu_relax();
+
+unlock:
+ spin_unlock_irqrestore(core->lock, irqflags);
+
return 0;
}

@@ -398,12 +471,12 @@ sam9x60_clk_register_frac_pll(struct regmap *regmap, spinlock_t *lock,
const char *name, const char *parent_name,
struct clk_hw *parent_hw, u8 id,
const struct clk_pll_characteristics *characteristics,
- const struct clk_pll_layout *layout, bool critical)
+ const struct clk_pll_layout *layout, u32 flags)
{
struct sam9x60_frac *frac;
struct clk_hw *hw;
struct clk_init_data init;
- unsigned long parent_rate, flags;
+ unsigned long parent_rate, irqflags;
unsigned int val;
int ret;

@@ -418,9 +491,7 @@ sam9x60_clk_register_frac_pll(struct regmap *regmap, spinlock_t *lock,
init.parent_names = &parent_name;
init.num_parents = 1;
init.ops = &sam9x60_frac_pll_ops;
- init.flags = CLK_SET_RATE_GATE;
- if (critical)
- init.flags |= CLK_IS_CRITICAL;
+ init.flags = flags;

frac->core.id = id;
frac->core.hw.init = &init;
@@ -429,7 +500,7 @@ sam9x60_clk_register_frac_pll(struct regmap *regmap, spinlock_t *lock,
frac->core.regmap = regmap;
frac->core.lock = lock;

- spin_lock_irqsave(frac->core.lock, flags);
+ spin_lock_irqsave(frac->core.lock, irqflags);
if (sam9x60_pll_ready(regmap, id)) {
regmap_update_bits(regmap, AT91_PMC_PLL_UPDT,
AT91_PMC_PLL_UPDT_ID_MSK, id);
@@ -457,7 +528,7 @@ sam9x60_clk_register_frac_pll(struct regmap *regmap, spinlock_t *lock,
goto free;
}
}
- spin_unlock_irqrestore(frac->core.lock, flags);
+ spin_unlock_irqrestore(frac->core.lock, irqflags);

hw = &frac->core.hw;
ret = clk_hw_register(NULL, hw);
@@ -469,7 +540,7 @@ sam9x60_clk_register_frac_pll(struct regmap *regmap, spinlock_t *lock,
return hw;

free:
- spin_unlock_irqrestore(frac->core.lock, flags);
+ spin_unlock_irqrestore(frac->core.lock, irqflags);
kfree(frac);
return hw;
}
@@ -478,12 +549,12 @@ struct clk_hw * __init
sam9x60_clk_register_div_pll(struct regmap *regmap, spinlock_t *lock,
const char *name, const char *parent_name, u8 id,
const struct clk_pll_characteristics *characteristics,
- const struct clk_pll_layout *layout, bool critical)
+ const struct clk_pll_layout *layout, u32 flags)
{
struct sam9x60_div *div;
struct clk_hw *hw;
struct clk_init_data init;
- unsigned long flags;
+ unsigned long irqflags;
unsigned int val;
int ret;

@@ -498,10 +569,7 @@ sam9x60_clk_register_div_pll(struct regmap *regmap, spinlock_t *lock,
init.parent_names = &parent_name;
init.num_parents = 1;
init.ops = &sam9x60_div_pll_ops;
- init.flags = CLK_SET_RATE_GATE | CLK_SET_PARENT_GATE |
- CLK_SET_RATE_PARENT;
- if (critical)
- init.flags |= CLK_IS_CRITICAL;
+ init.flags = flags;

div->core.id = id;
div->core.hw.init = &init;
@@ -510,14 +578,14 @@ sam9x60_clk_register_div_pll(struct regmap *regmap, spinlock_t *lock,
div->core.regmap = regmap;
div->core.lock = lock;

- spin_lock_irqsave(div->core.lock, flags);
+ spin_lock_irqsave(div->core.lock, irqflags);

regmap_update_bits(regmap, AT91_PMC_PLL_UPDT,
AT91_PMC_PLL_UPDT_ID_MSK, id);
regmap_read(regmap, AT91_PMC_PLL_CTRL0, &val);
div->div = FIELD_GET(PMC_PLL_CTRL0_DIV_MSK, val);

- spin_unlock_irqrestore(div->core.lock, flags);
+ spin_unlock_irqrestore(div->core.lock, irqflags);

hw = &div->core.hw;
ret = clk_hw_register(NULL, hw);
diff --git a/drivers/clk/at91/pmc.h b/drivers/clk/at91/pmc.h
index 7b86affc6d7c..364c9d4d7d51 100644
--- a/drivers/clk/at91/pmc.h
+++ b/drivers/clk/at91/pmc.h
@@ -190,14 +190,14 @@ struct clk_hw * __init
sam9x60_clk_register_div_pll(struct regmap *regmap, spinlock_t *lock,
const char *name, const char *parent_name, u8 id,
const struct clk_pll_characteristics *characteristics,
- const struct clk_pll_layout *layout, bool critical);
+ const struct clk_pll_layout *layout, u32 flags);

struct clk_hw * __init
sam9x60_clk_register_frac_pll(struct regmap *regmap, spinlock_t *lock,
const char *name, const char *parent_name,
struct clk_hw *parent_hw, u8 id,
const struct clk_pll_characteristics *characteristics,
- const struct clk_pll_layout *layout, bool critical);
+ const struct clk_pll_layout *layout, u32 flags);

struct clk_hw * __init
at91_clk_register_programmable(struct regmap *regmap, const char *name,
diff --git a/drivers/clk/at91/sam9x60.c b/drivers/clk/at91/sam9x60.c
index 3c4c95603595..e5094c69e606 100644
--- a/drivers/clk/at91/sam9x60.c
+++ b/drivers/clk/at91/sam9x60.c
@@ -228,13 +228,15 @@ static void __init sam9x60_pmc_setup(struct device_node *np)
hw = sam9x60_clk_register_frac_pll(regmap, &pmc_pll_lock, "pllack_fracck",
"mainck", sam9x60_pmc->chws[PMC_MAIN],
0, &plla_characteristics,
- &pll_frac_layout, true);
+ &pll_frac_layout,
+ CLK_IS_CRITICAL | CLK_SET_RATE_GATE);
if (IS_ERR(hw))
goto err_free;

hw = sam9x60_clk_register_div_pll(regmap, &pmc_pll_lock, "pllack_divck",
"pllack_fracck", 0, &plla_characteristics,
- &pll_div_layout, true);
+ &pll_div_layout,
+ CLK_IS_CRITICAL | CLK_SET_RATE_GATE);
if (IS_ERR(hw))
goto err_free;

@@ -243,13 +245,16 @@ static void __init sam9x60_pmc_setup(struct device_node *np)
hw = sam9x60_clk_register_frac_pll(regmap, &pmc_pll_lock, "upllck_fracck",
"main_osc", main_osc_hw, 1,
&upll_characteristics,
- &pll_frac_layout, false);
+ &pll_frac_layout, CLK_SET_RATE_GATE);
if (IS_ERR(hw))
goto err_free;

hw = sam9x60_clk_register_div_pll(regmap, &pmc_pll_lock, "upllck_divck",
"upllck_fracck", 1, &upll_characteristics,
- &pll_div_layout, false);
+ &pll_div_layout,
+ CLK_SET_RATE_GATE |
+ CLK_SET_PARENT_GATE |
+ CLK_SET_RATE_PARENT);
if (IS_ERR(hw))
goto err_free;

diff --git a/drivers/clk/at91/sama7g5.c b/drivers/clk/at91/sama7g5.c
index d3c3469d47d9..fdacd4410da6 100644
--- a/drivers/clk/at91/sama7g5.c
+++ b/drivers/clk/at91/sama7g5.c
@@ -95,15 +95,15 @@ static const struct clk_pll_layout pll_layout_divio = {
* @p: clock parent
* @l: clock layout
* @t: clock type
- * @f: true if clock is critical and cannot be disabled
+ * @f: clock flags
* @eid: export index in sama7g5->chws[] array
*/
static const struct {
const char *n;
const char *p;
const struct clk_pll_layout *l;
+ u32 f;
u8 t;
- u8 c;
u8 eid;
} sama7g5_plls[][PLL_ID_MAX] = {
[PLL_ID_CPU] = {
@@ -111,13 +111,13 @@ static const struct {
.p = "mainck",
.l = &pll_layout_frac,
.t = PLL_TYPE_FRAC,
- .c = 1, },
+ .f = CLK_IS_CRITICAL, },

{ .n = "cpupll_divpmcck",
.p = "cpupll_fracck",
.l = &pll_layout_divpmc,
.t = PLL_TYPE_DIV,
- .c = 1,
+ .f = CLK_IS_CRITICAL | CLK_SET_RATE_PARENT,
.eid = PMC_CPUPLL, },
},

@@ -126,13 +126,13 @@ static const struct {
.p = "mainck",
.l = &pll_layout_frac,
.t = PLL_TYPE_FRAC,
- .c = 1, },
+ .f = CLK_IS_CRITICAL | CLK_SET_RATE_GATE, },

{ .n = "syspll_divpmcck",
.p = "syspll_fracck",
.l = &pll_layout_divpmc,
.t = PLL_TYPE_DIV,
- .c = 1,
+ .f = CLK_IS_CRITICAL | CLK_SET_RATE_GATE,
.eid = PMC_SYSPLL, },
},

@@ -141,55 +141,66 @@ static const struct {
.p = "mainck",
.l = &pll_layout_frac,
.t = PLL_TYPE_FRAC,
- .c = 1, },
+ .f = CLK_IS_CRITICAL | CLK_SET_RATE_GATE, },

{ .n = "ddrpll_divpmcck",
.p = "ddrpll_fracck",
.l = &pll_layout_divpmc,
.t = PLL_TYPE_DIV,
- .c = 1, },
+ .f = CLK_IS_CRITICAL | CLK_SET_RATE_GATE, },
},

[PLL_ID_IMG] = {
{ .n = "imgpll_fracck",
.p = "mainck",
.l = &pll_layout_frac,
- .t = PLL_TYPE_FRAC, },
+ .t = PLL_TYPE_FRAC,
+ .f = CLK_SET_RATE_GATE, },

{ .n = "imgpll_divpmcck",
.p = "imgpll_fracck",
.l = &pll_layout_divpmc,
- .t = PLL_TYPE_DIV, },
+ .t = PLL_TYPE_DIV,
+ .f = CLK_SET_RATE_GATE | CLK_SET_PARENT_GATE |
+ CLK_SET_RATE_PARENT, },
},

[PLL_ID_BAUD] = {
{ .n = "baudpll_fracck",
.p = "mainck",
.l = &pll_layout_frac,
- .t = PLL_TYPE_FRAC, },
+ .t = PLL_TYPE_FRAC,
+ .f = CLK_SET_RATE_GATE, },

{ .n = "baudpll_divpmcck",
.p = "baudpll_fracck",
.l = &pll_layout_divpmc,
- .t = PLL_TYPE_DIV, },
+ .t = PLL_TYPE_DIV,
+ .f = CLK_SET_RATE_GATE | CLK_SET_PARENT_GATE |
+ CLK_SET_RATE_PARENT, },
},

[PLL_ID_AUDIO] = {
{ .n = "audiopll_fracck",
.p = "main_xtal",
.l = &pll_layout_frac,
- .t = PLL_TYPE_FRAC, },
+ .t = PLL_TYPE_FRAC,
+ .f = CLK_SET_RATE_GATE, },

{ .n = "audiopll_divpmcck",
.p = "audiopll_fracck",
.l = &pll_layout_divpmc,
.t = PLL_TYPE_DIV,
+ .f = CLK_SET_RATE_GATE | CLK_SET_PARENT_GATE |
+ CLK_SET_RATE_PARENT,
.eid = PMC_AUDIOPMCPLL, },

{ .n = "audiopll_diviock",
.p = "audiopll_fracck",
.l = &pll_layout_divio,
.t = PLL_TYPE_DIV,
+ .f = CLK_SET_RATE_GATE | CLK_SET_PARENT_GATE |
+ CLK_SET_RATE_PARENT,
.eid = PMC_AUDIOIOPLL, },
},

@@ -197,12 +208,15 @@ static const struct {
{ .n = "ethpll_fracck",
.p = "main_xtal",
.l = &pll_layout_frac,
- .t = PLL_TYPE_FRAC, },
+ .t = PLL_TYPE_FRAC,
+ .f = CLK_SET_RATE_GATE, },

{ .n = "ethpll_divpmcck",
.p = "ethpll_fracck",
.l = &pll_layout_divpmc,
- .t = PLL_TYPE_DIV, },
+ .t = PLL_TYPE_DIV,
+ .f = CLK_SET_RATE_GATE | CLK_SET_PARENT_GATE |
+ CLK_SET_RATE_PARENT, },
},
};

@@ -890,7 +904,7 @@ static void __init sama7g5_pmc_setup(struct device_node *np)
sama7g5_plls[i][j].p, parent_hw, i,
&pll_characteristics,
sama7g5_plls[i][j].l,
- sama7g5_plls[i][j].c);
+ sama7g5_plls[i][j].f);
break;

case PLL_TYPE_DIV:
@@ -899,7 +913,7 @@ static void __init sama7g5_pmc_setup(struct device_node *np)
sama7g5_plls[i][j].p, i,
&pll_characteristics,
sama7g5_plls[i][j].l,
- sama7g5_plls[i][j].c);
+ sama7g5_plls[i][j].f);
break;

default:
--
2.7.4
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