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path: root/drivers/clk/at91/clk-programmable.c
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Diffstat (limited to 'drivers/clk/at91/clk-programmable.c')
-rw-r--r--drivers/clk/at91/clk-programmable.c202
1 files changed, 61 insertions, 141 deletions
diff --git a/drivers/clk/at91/clk-programmable.c b/drivers/clk/at91/clk-programmable.c
index fd792b203eaf..62e2509f9df1 100644
--- a/drivers/clk/at91/clk-programmable.c
+++ b/drivers/clk/at91/clk-programmable.c
@@ -13,12 +13,9 @@
#include <linux/clk/at91_pmc.h>
#include <linux/of.h>
#include <linux/of_address.h>
-#include <linux/of_irq.h>
#include <linux/io.h>
#include <linux/wait.h>
#include <linux/sched.h>
-#include <linux/interrupt.h>
-#include <linux/irq.h>
#include "pmc.h"
@@ -38,104 +35,59 @@ struct clk_programmable_layout {
struct clk_programmable {
struct clk_hw hw;
struct at91_pmc *pmc;
- unsigned int irq;
- wait_queue_head_t wait;
u8 id;
- u8 css;
- u8 pres;
- u8 slckmck;
const struct clk_programmable_layout *layout;
};
#define to_clk_programmable(hw) container_of(hw, struct clk_programmable, hw)
-
-static irqreturn_t clk_programmable_irq_handler(int irq, void *dev_id)
-{
- struct clk_programmable *prog = (struct clk_programmable *)dev_id;
-
- wake_up(&prog->wait);
-
- return IRQ_HANDLED;
-}
-
-static int clk_programmable_prepare(struct clk_hw *hw)
+static unsigned long clk_programmable_recalc_rate(struct clk_hw *hw,
+ unsigned long parent_rate)
{
- u32 tmp;
+ u32 pres;
struct clk_programmable *prog = to_clk_programmable(hw);
struct at91_pmc *pmc = prog->pmc;
const struct clk_programmable_layout *layout = prog->layout;
- u8 id = prog->id;
- u32 mask = PROG_STATUS_MASK(id);
-
- tmp = prog->css | (prog->pres << layout->pres_shift);
- if (layout->have_slck_mck && prog->slckmck)
- tmp |= AT91_PMC_CSSMCK_MCK;
-
- pmc_write(pmc, AT91_PMC_PCKR(id), tmp);
-
- while (!(pmc_read(pmc, AT91_PMC_SR) & mask))
- wait_event(prog->wait, pmc_read(pmc, AT91_PMC_SR) & mask);
- return 0;
+ pres = (pmc_read(pmc, AT91_PMC_PCKR(prog->id)) >> layout->pres_shift) &
+ PROG_PRES_MASK;
+ return parent_rate >> pres;
}
-static int clk_programmable_is_ready(struct clk_hw *hw)
+static long clk_programmable_determine_rate(struct clk_hw *hw,
+ unsigned long rate,
+ unsigned long *best_parent_rate,
+ struct clk **best_parent_clk)
{
- struct clk_programmable *prog = to_clk_programmable(hw);
- struct at91_pmc *pmc = prog->pmc;
-
- return !!(pmc_read(pmc, AT91_PMC_SR) & AT91_PMC_PCKR(prog->id));
-}
+ struct clk *parent = NULL;
+ long best_rate = -EINVAL;
+ unsigned long parent_rate;
+ unsigned long tmp_rate;
+ int shift;
+ int i;
-static unsigned long clk_programmable_recalc_rate(struct clk_hw *hw,
- unsigned long parent_rate)
-{
- u32 tmp;
- struct clk_programmable *prog = to_clk_programmable(hw);
- struct at91_pmc *pmc = prog->pmc;
- const struct clk_programmable_layout *layout = prog->layout;
+ for (i = 0; i < __clk_get_num_parents(hw->clk); i++) {
+ parent = clk_get_parent_by_index(hw->clk, i);
+ if (!parent)
+ continue;
- tmp = pmc_read(pmc, AT91_PMC_PCKR(prog->id));
- prog->pres = (tmp >> layout->pres_shift) & PROG_PRES_MASK;
+ parent_rate = __clk_get_rate(parent);
+ for (shift = 0; shift < PROG_PRES_MASK; shift++) {
+ tmp_rate = parent_rate >> shift;
+ if (tmp_rate <= rate)
+ break;
+ }
- return parent_rate >> prog->pres;
-}
+ if (tmp_rate > rate)
+ continue;
-static long clk_programmable_round_rate(struct clk_hw *hw, unsigned long rate,
- unsigned long *parent_rate)
-{
- unsigned long best_rate = *parent_rate;
- unsigned long best_diff;
- unsigned long new_diff;
- unsigned long cur_rate;
- int shift = shift;
-
- if (rate > *parent_rate)
- return *parent_rate;
- else
- best_diff = *parent_rate - rate;
-
- if (!best_diff)
- return best_rate;
-
- for (shift = 1; shift < PROG_PRES_MASK; shift++) {
- cur_rate = *parent_rate >> shift;
-
- if (cur_rate > rate)
- new_diff = cur_rate - rate;
- else
- new_diff = rate - cur_rate;
-
- if (!new_diff)
- return cur_rate;
-
- if (new_diff < best_diff) {
- best_diff = new_diff;
- best_rate = cur_rate;
+ if (best_rate < 0 || (rate - tmp_rate) < (rate - best_rate)) {
+ best_rate = tmp_rate;
+ *best_parent_rate = parent_rate;
+ *best_parent_clk = parent;
}
- if (rate > cur_rate)
+ if (!best_rate)
break;
}
@@ -146,17 +98,22 @@ static int clk_programmable_set_parent(struct clk_hw *hw, u8 index)
{
struct clk_programmable *prog = to_clk_programmable(hw);
const struct clk_programmable_layout *layout = prog->layout;
+ struct at91_pmc *pmc = prog->pmc;
+ u32 tmp = pmc_read(pmc, AT91_PMC_PCKR(prog->id)) & ~layout->css_mask;
+
+ if (layout->have_slck_mck)
+ tmp &= AT91_PMC_CSSMCK_MCK;
+
if (index > layout->css_mask) {
if (index > PROG_MAX_RM9200_CSS && layout->have_slck_mck) {
- prog->css = 0;
- prog->slckmck = 1;
+ tmp |= AT91_PMC_CSSMCK_MCK;
return 0;
} else {
return -EINVAL;
}
}
- prog->css = index;
+ pmc_write(pmc, AT91_PMC_PCKR(prog->id), tmp | index);
return 0;
}
@@ -169,13 +126,9 @@ static u8 clk_programmable_get_parent(struct clk_hw *hw)
const struct clk_programmable_layout *layout = prog->layout;
tmp = pmc_read(pmc, AT91_PMC_PCKR(prog->id));
- prog->css = tmp & layout->css_mask;
- ret = prog->css;
- if (layout->have_slck_mck) {
- prog->slckmck = !!(tmp & AT91_PMC_CSSMCK_MCK);
- if (prog->slckmck && !ret)
- ret = PROG_MAX_RM9200_CSS + 1;
- }
+ ret = tmp & layout->css_mask;
+ if (layout->have_slck_mck && (tmp & AT91_PMC_CSSMCK_MCK) && !ret)
+ ret = PROG_MAX_RM9200_CSS + 1;
return ret;
}
@@ -184,67 +137,47 @@ static int clk_programmable_set_rate(struct clk_hw *hw, unsigned long rate,
unsigned long parent_rate)
{
struct clk_programmable *prog = to_clk_programmable(hw);
- unsigned long best_rate = parent_rate;
- unsigned long best_diff;
- unsigned long new_diff;
- unsigned long cur_rate;
+ struct at91_pmc *pmc = prog->pmc;
+ const struct clk_programmable_layout *layout = prog->layout;
+ unsigned long div = parent_rate / rate;
int shift = 0;
+ u32 tmp = pmc_read(pmc, AT91_PMC_PCKR(prog->id)) &
+ ~(PROG_PRES_MASK << layout->pres_shift);
- if (rate > parent_rate)
- return parent_rate;
- else
- best_diff = parent_rate - rate;
-
- if (!best_diff) {
- prog->pres = shift;
- return 0;
- }
+ if (!div)
+ return -EINVAL;
- for (shift = 1; shift < PROG_PRES_MASK; shift++) {
- cur_rate = parent_rate >> shift;
+ shift = fls(div) - 1;
- if (cur_rate > rate)
- new_diff = cur_rate - rate;
- else
- new_diff = rate - cur_rate;
+ if (div != (1<<shift))
+ return -EINVAL;
- if (!new_diff)
- break;
+ if (shift >= PROG_PRES_MASK)
+ return -EINVAL;
- if (new_diff < best_diff) {
- best_diff = new_diff;
- best_rate = cur_rate;
- }
+ pmc_write(pmc, AT91_PMC_PCKR(prog->id),
+ tmp | (shift << layout->pres_shift));
- if (rate > cur_rate)
- break;
- }
-
- prog->pres = shift;
return 0;
}
static const struct clk_ops programmable_ops = {
- .prepare = clk_programmable_prepare,
- .is_prepared = clk_programmable_is_ready,
.recalc_rate = clk_programmable_recalc_rate,
- .round_rate = clk_programmable_round_rate,
+ .determine_rate = clk_programmable_determine_rate,
.get_parent = clk_programmable_get_parent,
.set_parent = clk_programmable_set_parent,
.set_rate = clk_programmable_set_rate,
};
static struct clk * __init
-at91_clk_register_programmable(struct at91_pmc *pmc, unsigned int irq,
+at91_clk_register_programmable(struct at91_pmc *pmc,
const char *name, const char **parent_names,
u8 num_parents, u8 id,
const struct clk_programmable_layout *layout)
{
- int ret;
struct clk_programmable *prog;
struct clk *clk = NULL;
struct clk_init_data init;
- char irq_name[11];
if (id > PROG_ID_MAX)
return ERR_PTR(-EINVAL);
@@ -263,14 +196,6 @@ at91_clk_register_programmable(struct at91_pmc *pmc, unsigned int irq,
prog->layout = layout;
prog->hw.init = &init;
prog->pmc = pmc;
- prog->irq = irq;
- init_waitqueue_head(&prog->wait);
- irq_set_status_flags(prog->irq, IRQ_NOAUTOEN);
- snprintf(irq_name, sizeof(irq_name), "clk-prog%d", id);
- ret = request_irq(prog->irq, clk_programmable_irq_handler,
- IRQF_TRIGGER_HIGH, irq_name, prog);
- if (ret)
- return ERR_PTR(ret);
clk = clk_register(NULL, &prog->hw);
if (IS_ERR(clk))
@@ -304,7 +229,6 @@ of_at91_clk_prog_setup(struct device_node *np, struct at91_pmc *pmc,
int num;
u32 id;
int i;
- unsigned int irq;
struct clk *clk;
int num_parents;
const char *parent_names[PROG_SOURCE_MAX];
@@ -332,11 +256,7 @@ of_at91_clk_prog_setup(struct device_node *np, struct at91_pmc *pmc,
if (of_property_read_string(np, "clock-output-names", &name))
name = progclknp->name;
- irq = irq_of_parse_and_map(progclknp, 0);
- if (!irq)
- continue;
-
- clk = at91_clk_register_programmable(pmc, irq, name,
+ clk = at91_clk_register_programmable(pmc, name,
parent_names, num_parents,
id, layout);
if (IS_ERR(clk))
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