diff options
author | viresh kumar <viresh.kumar@st.com> | 2011-02-16 07:40:39 +0100 |
---|---|---|
committer | Russell King <rmk+kernel@arm.linux.org.uk> | 2011-03-09 09:49:45 +0000 |
commit | af89fd812b00a52c54a3b9b2290fae4d31c7be9a (patch) | |
tree | 3892de4165b23e98424f672c23b7a6d456ad235d /arch/arm/plat-spear/clock.c | |
parent | cf285434ac0880f94bf4afdd90b06a4655f56570 (diff) | |
download | op-kernel-dev-af89fd812b00a52c54a3b9b2290fae4d31c7be9a.zip op-kernel-dev-af89fd812b00a52c54a3b9b2290fae4d31c7be9a.tar.gz |
ARM: 6703/1: SPEAr: update clk API support
- Add support for divisor per parent clock
- Add ENABLED_ON_INIT feature in clk
- Add clk_set_rate(), round_rate_index & clk_round_rate()
- Simplify clk_recalc functions
- Add/update clock definitions
Reviewed-by: Stanley Miao <stanley.miao@windriver.com>
Signed-off-by: Viresh Kumar <viresh.kumar@st.com>
Signed-off-by: shiraz hashim <shiraz.hashim@st.com>
Signed-off-by: Rajeev Kumar <rajeev-dlh.kumar@st.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Diffstat (limited to 'arch/arm/plat-spear/clock.c')
-rw-r--r-- | arch/arm/plat-spear/clock.c | 705 |
1 files changed, 567 insertions, 138 deletions
diff --git a/arch/arm/plat-spear/clock.c b/arch/arm/plat-spear/clock.c index f1cf832..7e7ab60 100644 --- a/arch/arm/plat-spear/clock.c +++ b/arch/arm/plat-spear/clock.c @@ -12,6 +12,7 @@ */ #include <linux/bug.h> +#include <linux/clk.h> #include <linux/err.h> #include <linux/io.h> #include <linux/list.h> @@ -22,7 +23,7 @@ static DEFINE_SPINLOCK(clocks_lock); static LIST_HEAD(root_clks); -static void propagate_rate(struct list_head *); +static void propagate_rate(struct clk *, int on_init); static int generic_clk_enable(struct clk *clk) { @@ -64,6 +65,100 @@ static struct clkops generic_clkops = { .disable = generic_clk_disable, }; +/* returns current programmed clocks clock info structure */ +static struct pclk_info *pclk_info_get(struct clk *clk) +{ + unsigned int val, i; + struct pclk_info *info = NULL; + + val = (readl(clk->pclk_sel->pclk_sel_reg) >> clk->pclk_sel_shift) + & clk->pclk_sel->pclk_sel_mask; + + for (i = 0; i < clk->pclk_sel->pclk_count; i++) { + if (clk->pclk_sel->pclk_info[i].pclk_val == val) + info = &clk->pclk_sel->pclk_info[i]; + } + + return info; +} + +/* + * Set Update pclk, and pclk_info of clk and add clock sibling node to current + * parents children list + */ +static void clk_reparent(struct clk *clk, struct pclk_info *pclk_info) +{ + unsigned long flags; + + spin_lock_irqsave(&clocks_lock, flags); + list_del(&clk->sibling); + list_add(&clk->sibling, &pclk_info->pclk->children); + + clk->pclk = pclk_info->pclk; + spin_unlock_irqrestore(&clocks_lock, flags); +} + +static void do_clk_disable(struct clk *clk) +{ + if (!clk) + return; + + if (!clk->usage_count) { + WARN_ON(1); + return; + } + + clk->usage_count--; + + if (clk->usage_count == 0) { + /* + * Surely, there are no active childrens or direct users + * of this clock + */ + if (clk->pclk) + do_clk_disable(clk->pclk); + + if (clk->ops && clk->ops->disable) + clk->ops->disable(clk); + } +} + +static int do_clk_enable(struct clk *clk) +{ + int ret = 0; + + if (!clk) + return -EFAULT; + + if (clk->usage_count == 0) { + if (clk->pclk) { + ret = do_clk_enable(clk->pclk); + if (ret) + goto err; + } + if (clk->ops && clk->ops->enable) { + ret = clk->ops->enable(clk); + if (ret) { + if (clk->pclk) + do_clk_disable(clk->pclk); + goto err; + } + } + /* + * Since the clock is going to be used for the first + * time please reclac + */ + if (clk->recalc) { + ret = clk->recalc(clk); + if (ret) + goto err; + } + } + clk->usage_count++; +err: + return ret; +} + /* * clk_enable - inform the system when the clock source should be running. * @clk: clock source @@ -77,17 +172,9 @@ int clk_enable(struct clk *clk) unsigned long flags; int ret = 0; - if (!clk || IS_ERR(clk)) - return -EFAULT; - spin_lock_irqsave(&clocks_lock, flags); - if (clk->usage_count == 0) { - if (clk->ops && clk->ops->enable) - ret = clk->ops->enable(clk); - } - clk->usage_count++; + ret = do_clk_enable(clk); spin_unlock_irqrestore(&clocks_lock, flags); - return ret; } EXPORT_SYMBOL(clk_enable); @@ -108,17 +195,8 @@ void clk_disable(struct clk *clk) { unsigned long flags; - if (!clk || IS_ERR(clk)) - return; - - WARN_ON(clk->usage_count == 0); - spin_lock_irqsave(&clocks_lock, flags); - clk->usage_count--; - if (clk->usage_count == 0) { - if (clk->ops && clk->ops->disable) - clk->ops->disable(clk); - } + do_clk_disable(clk); spin_unlock_irqrestore(&clocks_lock, flags); } EXPORT_SYMBOL(clk_disable); @@ -152,15 +230,14 @@ int clk_set_parent(struct clk *clk, struct clk *parent) int i, found = 0, val = 0; unsigned long flags; - if (!clk || IS_ERR(clk) || !parent || IS_ERR(parent)) + if (!clk || !parent) return -EFAULT; - if (clk->usage_count) - return -EBUSY; - if (!clk->pclk_sel) - return -EPERM; if (clk->pclk == parent) return 0; + if (!clk->pclk_sel) + return -EPERM; + /* check if requested parent is in clk parent list */ for (i = 0; i < clk->pclk_sel->pclk_count; i++) { if (clk->pclk_sel->pclk_info[i].pclk == parent) { found = 1; @@ -175,13 +252,14 @@ int clk_set_parent(struct clk *clk, struct clk *parent) /* reflect parent change in hardware */ val = readl(clk->pclk_sel->pclk_sel_reg); val &= ~(clk->pclk_sel->pclk_sel_mask << clk->pclk_sel_shift); - val |= clk->pclk_sel->pclk_info[i].pclk_mask << clk->pclk_sel_shift; + val |= clk->pclk_sel->pclk_info[i].pclk_val << clk->pclk_sel_shift; writel(val, clk->pclk_sel->pclk_sel_reg); spin_unlock_irqrestore(&clocks_lock, flags); /* reflect parent change in software */ - clk->recalc(clk); - propagate_rate(&clk->children); + clk_reparent(clk, &clk->pclk_sel->pclk_info[i]); + + propagate_rate(clk, 0); return 0; } EXPORT_SYMBOL(clk_set_parent); @@ -195,19 +273,37 @@ EXPORT_SYMBOL(clk_set_parent); */ int clk_set_rate(struct clk *clk, unsigned long rate) { - /* TODO */ - return -EINVAL; + unsigned long flags; + int ret = -EINVAL; + + if (!clk || !rate) + return -EFAULT; + + if (clk->set_rate) { + spin_lock_irqsave(&clocks_lock, flags); + ret = clk->set_rate(clk, rate); + if (!ret) + /* if successful -> propagate */ + propagate_rate(clk, 0); + spin_unlock_irqrestore(&clocks_lock, flags); + } else if (clk->pclk) { + u32 mult = clk->div_factor ? clk->div_factor : 1; + ret = clk_set_rate(clk->pclk, mult * rate); + } + + return ret; } EXPORT_SYMBOL(clk_set_rate); /* registers clock in platform clock framework */ void clk_register(struct clk_lookup *cl) { - struct clk *clk = cl->clk; + struct clk *clk; unsigned long flags; - if (!clk || IS_ERR(clk)) + if (!cl || !cl->clk) return; + clk = cl->clk; spin_lock_irqsave(&clocks_lock, flags); @@ -220,15 +316,24 @@ void clk_register(struct clk_lookup *cl) /* root clock don't have any parents */ if (!clk->pclk && !clk->pclk_sel) { list_add(&clk->sibling, &root_clks); - /* add clocks with only one parent to parent's children list */ } else if (clk->pclk && !clk->pclk_sel) { + /* add clocks with only one parent to parent's children list */ list_add(&clk->sibling, &clk->pclk->children); } else { - /* add clocks with > 1 parent to 1st parent's children list */ - clk->pclk = clk->pclk_sel->pclk_info[0].pclk; - list_add(&clk->sibling, - &clk->pclk_sel->pclk_info[0].pclk->children); + /* clocks with more than one parent */ + struct pclk_info *pclk_info; + + pclk_info = pclk_info_get(clk); + if (!pclk_info) { + pr_err("CLKDEV: invalid pclk info of clk with" + " %s dev_id and %s con_id\n", + cl->dev_id, cl->con_id); + } else { + clk->pclk = pclk_info->pclk; + list_add(&clk->sibling, &pclk_info->pclk->children); + } } + spin_unlock_irqrestore(&clocks_lock, flags); /* add clock to arm clockdev framework */ @@ -236,56 +341,142 @@ void clk_register(struct clk_lookup *cl) } /** - * propagate_rate - recalculate and propagate all clocks in list head + * propagate_rate - recalculate and propagate all clocks to children + * @pclk: parent clock required to be propogated + * @on_init: flag for enabling clocks which are ENABLED_ON_INIT. * - * Recalculates all root clocks in list head, which if the clock's .recalc is - * set correctly, should also propagate their rates. + * Recalculates all children clocks */ -static void propagate_rate(struct list_head *lhead) +void propagate_rate(struct clk *pclk, int on_init) { - struct clk *clkp, *_temp; + struct clk *clk, *_temp; + int ret = 0; + + list_for_each_entry_safe(clk, _temp, &pclk->children, sibling) { + if (clk->recalc) { + ret = clk->recalc(clk); + /* + * recalc will return error if clk out is not programmed + * In this case configure default rate. + */ + if (ret && clk->set_rate) + clk->set_rate(clk, 0); + } + propagate_rate(clk, on_init); + + if (!on_init) + continue; - list_for_each_entry_safe(clkp, _temp, lhead, sibling) { - if (clkp->recalc) - clkp->recalc(clkp); - propagate_rate(&clkp->children); + /* Enable clks enabled on init, in software view */ + if (clk->flags & ENABLED_ON_INIT) + do_clk_enable(clk); } } -/* returns current programmed clocks clock info structure */ -static struct pclk_info *pclk_info_get(struct clk *clk) +/** + * round_rate_index - return closest programmable rate index in rate_config tbl + * @clk: ptr to clock structure + * @drate: desired rate + * @rate: final rate will be returned in this variable only. + * + * Finds index in rate_config for highest clk rate which is less than + * requested rate. If there is no clk rate lesser than requested rate then + * -EINVAL is returned. This routine assumes that rate_config is written + * in incrementing order of clk rates. + * If drate passed is zero then default rate is programmed. + */ +static int +round_rate_index(struct clk *clk, unsigned long drate, unsigned long *rate) { - unsigned int mask, i; - unsigned long flags; - struct pclk_info *info = NULL; + unsigned long tmp = 0, prev_rate = 0; + int index; - spin_lock_irqsave(&clocks_lock, flags); - mask = (readl(clk->pclk_sel->pclk_sel_reg) >> clk->pclk_sel_shift) - & clk->pclk_sel->pclk_sel_mask; + if (!clk->calc_rate) + return -EFAULT; - for (i = 0; i < clk->pclk_sel->pclk_count; i++) { - if (clk->pclk_sel->pclk_info[i].pclk_mask == mask) - info = &clk->pclk_sel->pclk_info[i]; + if (!drate) + return -EINVAL; + + /* + * This loops ends on two conditions: + * - as soon as clk is found with rate greater than requested rate. + * - if all clks in rate_config are smaller than requested rate. + */ + for (index = 0; index < clk->rate_config.count; index++) { + prev_rate = tmp; + tmp = clk->calc_rate(clk, index); + if (drate < tmp) { + index--; + break; + } } - spin_unlock_irqrestore(&clocks_lock, flags); + /* return if can't find suitable clock */ + if (index < 0) { + index = -EINVAL; + *rate = 0; + } else if (index == clk->rate_config.count) { + /* program with highest clk rate possible */ + index = clk->rate_config.count - 1; + *rate = tmp; + } else + *rate = prev_rate; - return info; + return index; } -/* - * Set pclk as cclk's parent and add clock sibling node to current parents - * children list +/** + * clk_round_rate - adjust a rate to the exact rate a clock can provide + * @clk: clock source + * @rate: desired clock rate in Hz + * + * Returns rounded clock rate in Hz, or negative errno. */ -static void change_parent(struct clk *cclk, struct clk *pclk) +long clk_round_rate(struct clk *clk, unsigned long drate) { - unsigned long flags; + long rate = 0; + int index; + + /* + * propagate call to parent who supports calc_rate. Similar approach is + * used in clk_set_rate. + */ + if (!clk->calc_rate) { + u32 mult; + if (!clk->pclk) + return clk->rate; + + mult = clk->div_factor ? clk->div_factor : 1; + return clk_round_rate(clk->pclk, mult * drate) / mult; + } - spin_lock_irqsave(&clocks_lock, flags); - list_del(&cclk->sibling); - list_add(&cclk->sibling, &pclk->children); + index = round_rate_index(clk, drate, &rate); + if (index >= 0) + return rate; + else + return index; +} +EXPORT_SYMBOL(clk_round_rate); - cclk->pclk = pclk; - spin_unlock_irqrestore(&clocks_lock, flags); +/*All below functions are called with lock held */ + +/* + * Calculates pll clk rate for specific value of mode, m, n and p + * + * In normal mode + * rate = (2 * M[15:8] * Fin)/(N * 2^P) + * + * In Dithered mode + * rate = (2 * M[15:0] * Fin)/(256 * N * 2^P) + */ +unsigned long pll_calc_rate(struct clk *clk, int index) +{ + unsigned long rate = clk->pclk->rate; + struct pll_rate_tbl *tbls = clk->rate_config.tbls; + unsigned int mode; + + mode = tbls[index].mode ? 256 : 1; + return (((2 * rate / 10000) * tbls[index].m) / + (mode * tbls[index].n * (1 << tbls[index].p))) * 10000; } /* @@ -297,13 +488,11 @@ static void change_parent(struct clk *cclk, struct clk *pclk) * In Dithered mode * rate = (2 * M[15:0] * Fin)/(256 * N * 2^P) */ -void pll_clk_recalc(struct clk *clk) +int pll_clk_recalc(struct clk *clk) { struct pll_clk_config *config = clk->private_data; unsigned int num = 2, den = 0, val, mode = 0; - unsigned long flags; - spin_lock_irqsave(&clocks_lock, flags); mode = (readl(config->mode_reg) >> config->masks->mode_shift) & config->masks->mode_mask; @@ -325,22 +514,120 @@ void pll_clk_recalc(struct clk *clk) den *= 256; } + if (!den) + return -EINVAL; + clk->rate = (((clk->pclk->rate/10000) * num) / den) * 10000; - spin_unlock_irqrestore(&clocks_lock, flags); + return 0; +} + +/* + * Configures new clock rate of pll + */ +int pll_clk_set_rate(struct clk *clk, unsigned long desired_rate) +{ + struct pll_rate_tbl *tbls = clk->rate_config.tbls; + struct pll_clk_config *config = clk->private_data; + unsigned long val, rate; + int i; + + i = round_rate_index(clk, desired_rate, &rate); + if (i < 0) + return i; + + val = readl(config->mode_reg) & + ~(config->masks->mode_mask << config->masks->mode_shift); + val |= (tbls[i].mode & config->masks->mode_mask) << + config->masks->mode_shift; + writel(val, config->mode_reg); + + val = readl(config->cfg_reg) & + ~(config->masks->div_p_mask << config->masks->div_p_shift); + val |= (tbls[i].p & config->masks->div_p_mask) << + config->masks->div_p_shift; + val &= ~(config->masks->div_n_mask << config->masks->div_n_shift); + val |= (tbls[i].n & config->masks->div_n_mask) << + config->masks->div_n_shift; + val &= ~(config->masks->dith_fdbk_m_mask << + config->masks->dith_fdbk_m_shift); + if (tbls[i].mode) + val |= (tbls[i].m & config->masks->dith_fdbk_m_mask) << + config->masks->dith_fdbk_m_shift; + else + val |= (tbls[i].m & config->masks->norm_fdbk_m_mask) << + config->masks->norm_fdbk_m_shift; + + writel(val, config->cfg_reg); + + clk->rate = rate; + + return 0; +} + +/* + * Calculates ahb, apb clk rate for specific value of div + */ +unsigned long bus_calc_rate(struct clk *clk, int index) +{ + unsigned long rate = clk->pclk->rate; + struct bus_rate_tbl *tbls = clk->rate_config.tbls; + + return rate / (tbls[index].div + 1); } /* calculates current programmed rate of ahb or apb bus */ -void bus_clk_recalc(struct clk *clk) +int bus_clk_recalc(struct clk *clk) { struct bus_clk_config *config = clk->private_data; unsigned int div; - unsigned long flags; - spin_lock_irqsave(&clocks_lock, flags); div = ((readl(config->reg) >> config->masks->shift) & config->masks->mask) + 1; + + if (!div) + return -EINVAL; + clk->rate = (unsigned long)clk->pclk->rate / div; - spin_unlock_irqrestore(&clocks_lock, flags); + return 0; +} + +/* Configures new clock rate of AHB OR APB bus */ +int bus_clk_set_rate(struct clk *clk, unsigned long desired_rate) +{ + struct bus_rate_tbl *tbls = clk->rate_config.tbls; + struct bus_clk_config *config = clk->private_data; + unsigned long val, rate; + int i; + + i = round_rate_index(clk, desired_rate, &rate); + if (i < 0) + return i; + + val = readl(config->reg) & + ~(config->masks->mask << config->masks->shift); + val |= (tbls[i].div & config->masks->mask) << config->masks->shift; + writel(val, config->reg); + + clk->rate = rate; + + return 0; +} + +/* + * gives rate for different values of eq, x and y + * + * Fout from synthesizer can be given from two equations: + * Fout1 = (Fin * X/Y)/2 EQ1 + * Fout2 = Fin * X/Y EQ2 + */ +unsigned long aux_calc_rate(struct clk *clk, int index) +{ + unsigned long rate = clk->pclk->rate; + struct aux_rate_tbl *tbls = clk->rate_config.tbls; + u8 eq = tbls[index].eq ? 1 : 2; + + return (((rate/10000) * tbls[index].xscale) / + (tbls[index].yscale * eq)) * 10000; } /* @@ -353,47 +640,76 @@ void bus_clk_recalc(struct clk *clk) * * Selection of eqn 1 or 2 is programmed in register */ -void aux_clk_recalc(struct clk *clk) +int aux_clk_recalc(struct clk *clk) { struct aux_clk_config *config = clk->private_data; - struct pclk_info *pclk_info = NULL; unsigned int num = 1, den = 1, val, eqn; - unsigned long flags; - /* get current programmed parent */ - pclk_info = pclk_info_get(clk); - if (!pclk_info) { - spin_lock_irqsave(&clocks_lock, flags); - clk->pclk = NULL; - clk->rate = 0; - spin_unlock_irqrestore(&clocks_lock, flags); - return; - } + val = readl(config->synth_reg); - change_parent(clk, pclk_info->pclk); + eqn = (val >> config->masks->eq_sel_shift) & + config->masks->eq_sel_mask; + if (eqn == config->masks->eq1_mask) + den *= 2; - spin_lock_irqsave(&clocks_lock, flags); - if (pclk_info->scalable) { - val = readl(config->synth_reg); - - eqn = (val >> config->masks->eq_sel_shift) & - config->masks->eq_sel_mask; - if (eqn == config->masks->eq1_mask) - den *= 2; - - /* calculate numerator */ - num = (val >> config->masks->xscale_sel_shift) & - config->masks->xscale_sel_mask; - - /* calculate denominator */ - den *= (val >> config->masks->yscale_sel_shift) & - config->masks->yscale_sel_mask; - val = (((clk->pclk->rate/10000) * num) / den) * 10000; - } else - val = clk->pclk->rate; + /* calculate numerator */ + num = (val >> config->masks->xscale_sel_shift) & + config->masks->xscale_sel_mask; - clk->rate = val; - spin_unlock_irqrestore(&clocks_lock, flags); + /* calculate denominator */ + den *= (val >> config->masks->yscale_sel_shift) & + config->masks->yscale_sel_mask; + + if (!den) + return -EINVAL; + + clk->rate = (((clk->pclk->rate/10000) * num) / den) * 10000; + return 0; +} + +/* Configures new clock rate of auxiliary synthesizers used by: UART, FIRDA*/ +int aux_clk_set_rate(struct clk *clk, unsigned long desired_rate) +{ + struct aux_rate_tbl *tbls = clk->rate_config.tbls; + struct aux_clk_config *config = clk->private_data; + unsigned long val, rate; + int i; + + i = round_rate_index(clk, desired_rate, &rate); + if (i < 0) + return i; + + val = readl(config->synth_reg) & + ~(config->masks->eq_sel_mask << config->masks->eq_sel_shift); + val |= (tbls[i].eq & config->masks->eq_sel_mask) << + config->masks->eq_sel_shift; + val &= ~(config->masks->xscale_sel_mask << + config->masks->xscale_sel_shift); + val |= (tbls[i].xscale & config->masks->xscale_sel_mask) << + config->masks->xscale_sel_shift; + val &= ~(config->masks->yscale_sel_mask << + config->masks->yscale_sel_shift); + val |= (tbls[i].yscale & config->masks->yscale_sel_mask) << + config->masks->yscale_sel_shift; + writel(val, config->synth_reg); + + clk->rate = rate; + + return 0; +} + +/* + * Calculates gpt clk rate for different values of mscale and nscale + * + * Fout= Fin/((2 ^ (N+1)) * (M+1)) + */ +unsigned long gpt_calc_rate(struct clk *clk, int index) +{ + unsigned long rate = clk->pclk->rate; + struct gpt_rate_tbl *tbls = clk->rate_config.tbls; + + return rate / ((1 << (tbls[index].nscale + 1)) * + (tbls[index].mscale + 1)); } /* @@ -401,49 +717,142 @@ void aux_clk_recalc(struct clk *clk) * Fout from synthesizer can be given from below equations: * Fout= Fin/((2 ^ (N+1)) * (M+1)) */ -void gpt_clk_recalc(struct clk *clk) +int gpt_clk_recalc(struct clk *clk) { struct gpt_clk_config *config = clk->private_data; - struct pclk_info *pclk_info = NULL; unsigned int div = 1, val; - unsigned long flags; - pclk_info = pclk_info_get(clk); - if (!pclk_info) { - spin_lock_irqsave(&clocks_lock, flags); - clk->pclk = NULL; - clk->rate = 0; - spin_unlock_irqrestore(&clocks_lock, flags); - return; - } + val = readl(config->synth_reg); + div += (val >> config->masks->mscale_sel_shift) & + config->masks->mscale_sel_mask; + div *= 1 << (((val >> config->masks->nscale_sel_shift) & + config->masks->nscale_sel_mask) + 1); - change_parent(clk, pclk_info->pclk); - - spin_lock_irqsave(&clocks_lock, flags); - if (pclk_info->scalable) { - val = readl(config->synth_reg); - div += (val >> config->masks->mscale_sel_shift) & - config->masks->mscale_sel_mask; - div *= 1 << (((val >> config->masks->nscale_sel_shift) & - config->masks->nscale_sel_mask) + 1); - } + if (!div) + return -EINVAL; clk->rate = (unsigned long)clk->pclk->rate / div; - spin_unlock_irqrestore(&clocks_lock, flags); + return 0; +} + +/* Configures new clock rate of gptiliary synthesizers used by: UART, FIRDA*/ +int gpt_clk_set_rate(struct clk *clk, unsigned long desired_rate) +{ + struct gpt_rate_tbl *tbls = clk->rate_config.tbls; + struct gpt_clk_config *config = clk->private_data; + unsigned long val, rate; + int i; + + i = round_rate_index(clk, desired_rate, &rate); + if (i < 0) + return i; + + val = readl(config->synth_reg) & ~(config->masks->mscale_sel_mask << + config->masks->mscale_sel_shift); + val |= (tbls[i].mscale & config->masks->mscale_sel_mask) << + config->masks->mscale_sel_shift; + val &= ~(config->masks->nscale_sel_mask << + config->masks->nscale_sel_shift); + val |= (tbls[i].nscale & config->masks->nscale_sel_mask) << + config->masks->nscale_sel_shift; + writel(val, config->synth_reg); + + clk->rate = rate; + + return 0; +} + +/* + * Calculates clcd clk rate for different values of div + * + * Fout from synthesizer can be given from below equation: + * Fout= Fin/2*div (division factor) + * div is 17 bits:- + * 0-13 (fractional part) + * 14-16 (integer part) + * To calculate Fout we left shift val by 14 bits and divide Fin by + * complete div (including fractional part) and then right shift the + * result by 14 places. + */ +unsigned long clcd_calc_rate(struct clk *clk, int index) +{ + unsigned long rate = clk->pclk->rate; + struct clcd_rate_tbl *tbls = clk->rate_config.tbls; + + rate /= 1000; + rate <<= 12; + rate /= (2 * tbls[index].div); + rate >>= 12; + rate *= 1000; + + return rate; +} + +/* + * calculates current programmed rate of clcd synthesizer + * Fout from synthesizer can be given from below equation: + * Fout= Fin/2*div (division factor) + * div is 17 bits:- + * 0-13 (fractional part) + * 14-16 (integer part) + * To calculate Fout we left shift val by 14 bits and divide Fin by + * complete div (including fractional part) and then right shift the + * result by 14 places. + */ +int clcd_clk_recalc(struct clk *clk) +{ + struct clcd_clk_config *config = clk->private_data; + unsigned int div = 1; + unsigned long prate; + unsigned int val; + + val = readl(config->synth_reg); + div = (val >> config->masks->div_factor_shift) & + config->masks->div_factor_mask; + + if (!div) + return -EINVAL; + + prate = clk->pclk->rate / 1000; /* first level division, make it KHz */ + + clk->rate = (((unsigned long)prate << 12) / (2 * div)) >> 12; + clk->rate *= 1000; + return 0; +} + +/* Configures new clock rate of auxiliary synthesizers used by: UART, FIRDA*/ +int clcd_clk_set_rate(struct clk *clk, unsigned long desired_rate) +{ + struct clcd_rate_tbl *tbls = clk->rate_config.tbls; + struct clcd_clk_config *config = clk->private_data; + unsigned long val, rate; + int i; + + i = round_rate_index(clk, desired_rate, &rate); + if (i < 0) + return i; + + val = readl(config->synth_reg) & ~(config->masks->div_factor_mask << + config->masks->div_factor_shift); + val |= (tbls[i].div & config->masks->div_factor_mask) << + config->masks->div_factor_shift; + writel(val, config->synth_reg); + + clk->rate = rate; + + return 0; } /* * Used for clocks that always have value as the parent clock divided by a * fixed divisor */ -void follow_parent(struct clk *clk) +int follow_parent(struct clk *clk) { - unsigned long flags; unsigned int div_factor = (clk->div_factor < 1) ? 1 : clk->div_factor; - spin_lock_irqsave(&clocks_lock, flags); clk->rate = clk->pclk->rate/div_factor; - spin_unlock_irqrestore(&clocks_lock, flags); + return 0; } /** @@ -454,5 +863,25 @@ void follow_parent(struct clk *clk) */ void recalc_root_clocks(void) { - propagate_rate(&root_clks); + struct clk *pclk; + unsigned long flags; + int ret = 0; + + spin_lock_irqsave(&clocks_lock, flags); + list_for_each_entry(pclk, &root_clks, sibling) { + if (pclk->recalc) { + ret = pclk->recalc(pclk); + /* + * recalc will return error if clk out is not programmed + * In this case configure default clock. + */ + if (ret && pclk->set_rate) + pclk->set_rate(pclk, 0); + } + propagate_rate(pclk, 1); + /* Enable clks enabled on init, in software view */ + if (pclk->flags & ENABLED_ON_INIT) + do_clk_enable(pclk); + } + spin_unlock_irqrestore(&clocks_lock, flags); } |