diff options
Diffstat (limited to 'arch/arm/mach-davinci/clock.c')
-rw-r--r-- | arch/arm/mach-davinci/clock.c | 75 |
1 files changed, 74 insertions, 1 deletions
diff --git a/arch/arm/mach-davinci/clock.c b/arch/arm/mach-davinci/clock.c index 054c303caead..01ba080433db 100644 --- a/arch/arm/mach-davinci/clock.c +++ b/arch/arm/mach-davinci/clock.c @@ -236,7 +236,7 @@ static int __init clk_disable_unused(void) if (!davinci_psc_is_clk_active(ck->gpsc, ck->lpsc)) continue; - pr_info("Clocks: disable unused %s\n", ck->name); + pr_debug("Clocks: disable unused %s\n", ck->name); davinci_psc_config(psc_domain(ck), ck->gpsc, ck->lpsc, (ck->flags & PSC_SWRSTDISABLE) ? @@ -287,6 +287,79 @@ static unsigned long clk_sysclk_recalc(struct clk *clk) return rate; } +int davinci_set_sysclk_rate(struct clk *clk, unsigned long rate) +{ + unsigned v; + struct pll_data *pll; + unsigned long input; + unsigned ratio = 0; + + /* If this is the PLL base clock, wrong function to call */ + if (clk->pll_data) + return -EINVAL; + + /* There must be a parent... */ + if (WARN_ON(!clk->parent)) + return -EINVAL; + + /* ... the parent must be a PLL... */ + if (WARN_ON(!clk->parent->pll_data)) + return -EINVAL; + + /* ... and this clock must have a divider. */ + if (WARN_ON(!clk->div_reg)) + return -EINVAL; + + pll = clk->parent->pll_data; + + input = clk->parent->rate; + + /* If pre-PLL, source clock is before the multiplier and divider(s) */ + if (clk->flags & PRE_PLL) + input = pll->input_rate; + + if (input > rate) { + /* + * Can afford to provide an output little higher than requested + * only if maximum rate supported by hardware on this sysclk + * is known. + */ + if (clk->maxrate) { + ratio = DIV_ROUND_CLOSEST(input, rate); + if (input / ratio > clk->maxrate) + ratio = 0; + } + + if (ratio == 0) + ratio = DIV_ROUND_UP(input, rate); + + ratio--; + } + + if (ratio > PLLDIV_RATIO_MASK) + return -EINVAL; + + do { + v = __raw_readl(pll->base + PLLSTAT); + } while (v & PLLSTAT_GOSTAT); + + v = __raw_readl(pll->base + clk->div_reg); + v &= ~PLLDIV_RATIO_MASK; + v |= ratio | PLLDIV_EN; + __raw_writel(v, pll->base + clk->div_reg); + + v = __raw_readl(pll->base + PLLCMD); + v |= PLLCMD_GOSET; + __raw_writel(v, pll->base + PLLCMD); + + do { + v = __raw_readl(pll->base + PLLSTAT); + } while (v & PLLSTAT_GOSTAT); + + return 0; +} +EXPORT_SYMBOL(davinci_set_sysclk_rate); + static unsigned long clk_leafclk_recalc(struct clk *clk) { if (WARN_ON(!clk->parent)) |