diff options
Diffstat (limited to 'drivers/clk/at91/clk-programmable.c')
-rw-r--r-- | drivers/clk/at91/clk-programmable.c | 202 |
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)) |