diff options
Diffstat (limited to 'drivers/clk/sunxi/clk-sunxi.c')
-rw-r--r-- | drivers/clk/sunxi/clk-sunxi.c | 262 |
1 files changed, 222 insertions, 40 deletions
diff --git a/drivers/clk/sunxi/clk-sunxi.c b/drivers/clk/sunxi/clk-sunxi.c index 1818f40..379324e 100644 --- a/drivers/clk/sunxi/clk-sunxi.c +++ b/drivers/clk/sunxi/clk-sunxi.c @@ -20,11 +20,221 @@ #include <linux/of_address.h> #include <linux/reset-controller.h> #include <linux/spinlock.h> +#include <linux/log2.h> #include "clk-factors.h" static DEFINE_SPINLOCK(clk_lock); +/** + * sun6i_a31_ahb1_clk_setup() - Setup function for a31 ahb1 composite clk + */ + +#define SUN6I_AHB1_MAX_PARENTS 4 +#define SUN6I_AHB1_MUX_PARENT_PLL6 3 +#define SUN6I_AHB1_MUX_SHIFT 12 +/* un-shifted mask is what mux_clk expects */ +#define SUN6I_AHB1_MUX_MASK 0x3 +#define SUN6I_AHB1_MUX_GET_PARENT(reg) ((reg >> SUN6I_AHB1_MUX_SHIFT) & \ + SUN6I_AHB1_MUX_MASK) + +#define SUN6I_AHB1_DIV_SHIFT 4 +#define SUN6I_AHB1_DIV_MASK (0x3 << SUN6I_AHB1_DIV_SHIFT) +#define SUN6I_AHB1_DIV_GET(reg) ((reg & SUN6I_AHB1_DIV_MASK) >> \ + SUN6I_AHB1_DIV_SHIFT) +#define SUN6I_AHB1_DIV_SET(reg, div) ((reg & ~SUN6I_AHB1_DIV_MASK) | \ + (div << SUN6I_AHB1_DIV_SHIFT)) +#define SUN6I_AHB1_PLL6_DIV_SHIFT 6 +#define SUN6I_AHB1_PLL6_DIV_MASK (0x3 << SUN6I_AHB1_PLL6_DIV_SHIFT) +#define SUN6I_AHB1_PLL6_DIV_GET(reg) ((reg & SUN6I_AHB1_PLL6_DIV_MASK) >> \ + SUN6I_AHB1_PLL6_DIV_SHIFT) +#define SUN6I_AHB1_PLL6_DIV_SET(reg, div) ((reg & ~SUN6I_AHB1_PLL6_DIV_MASK) | \ + (div << SUN6I_AHB1_PLL6_DIV_SHIFT)) + +struct sun6i_ahb1_clk { + struct clk_hw hw; + void __iomem *reg; +}; + +#define to_sun6i_ahb1_clk(_hw) container_of(_hw, struct sun6i_ahb1_clk, hw) + +static unsigned long sun6i_ahb1_clk_recalc_rate(struct clk_hw *hw, + unsigned long parent_rate) +{ + struct sun6i_ahb1_clk *ahb1 = to_sun6i_ahb1_clk(hw); + unsigned long rate; + u32 reg; + + /* Fetch the register value */ + reg = readl(ahb1->reg); + + /* apply pre-divider first if parent is pll6 */ + if (SUN6I_AHB1_MUX_GET_PARENT(reg) == SUN6I_AHB1_MUX_PARENT_PLL6) + parent_rate /= SUN6I_AHB1_PLL6_DIV_GET(reg) + 1; + + /* clk divider */ + rate = parent_rate >> SUN6I_AHB1_DIV_GET(reg); + + return rate; +} + +static long sun6i_ahb1_clk_round(unsigned long rate, u8 *divp, u8 *pre_divp, + u8 parent, unsigned long parent_rate) +{ + u8 div, calcp, calcm = 1; + + /* + * clock can only divide, so we will never be able to achieve + * frequencies higher than the parent frequency + */ + if (parent_rate && rate > parent_rate) + rate = parent_rate; + + div = DIV_ROUND_UP(parent_rate, rate); + + /* calculate pre-divider if parent is pll6 */ + if (parent == SUN6I_AHB1_MUX_PARENT_PLL6) { + if (div < 4) + calcp = 0; + else if (div / 2 < 4) + calcp = 1; + else if (div / 4 < 4) + calcp = 2; + else + calcp = 3; + + calcm = DIV_ROUND_UP(div, 1 << calcp); + } else { + calcp = __roundup_pow_of_two(div); + calcp = calcp > 3 ? 3 : calcp; + } + + /* we were asked to pass back divider values */ + if (divp) { + *divp = calcp; + *pre_divp = calcm - 1; + } + + return (parent_rate / calcm) >> calcp; +} + +static long sun6i_ahb1_clk_determine_rate(struct clk_hw *hw, unsigned long rate, + unsigned long min_rate, + unsigned long max_rate, + unsigned long *best_parent_rate, + struct clk_hw **best_parent_clk) +{ + struct clk *clk = hw->clk, *parent, *best_parent = NULL; + int i, num_parents; + unsigned long parent_rate, best = 0, child_rate, best_child_rate = 0; + + /* find the parent that can help provide the fastest rate <= rate */ + num_parents = __clk_get_num_parents(clk); + for (i = 0; i < num_parents; i++) { + parent = clk_get_parent_by_index(clk, i); + if (!parent) + continue; + if (__clk_get_flags(clk) & CLK_SET_RATE_PARENT) + parent_rate = __clk_round_rate(parent, rate); + else + parent_rate = __clk_get_rate(parent); + + child_rate = sun6i_ahb1_clk_round(rate, NULL, NULL, i, + parent_rate); + + if (child_rate <= rate && child_rate > best_child_rate) { + best_parent = parent; + best = parent_rate; + best_child_rate = child_rate; + } + } + + if (best_parent) + *best_parent_clk = __clk_get_hw(best_parent); + *best_parent_rate = best; + + return best_child_rate; +} + +static int sun6i_ahb1_clk_set_rate(struct clk_hw *hw, unsigned long rate, + unsigned long parent_rate) +{ + struct sun6i_ahb1_clk *ahb1 = to_sun6i_ahb1_clk(hw); + unsigned long flags; + u8 div, pre_div, parent; + u32 reg; + + spin_lock_irqsave(&clk_lock, flags); + + reg = readl(ahb1->reg); + + /* need to know which parent is used to apply pre-divider */ + parent = SUN6I_AHB1_MUX_GET_PARENT(reg); + sun6i_ahb1_clk_round(rate, &div, &pre_div, parent, parent_rate); + + reg = SUN6I_AHB1_DIV_SET(reg, div); + reg = SUN6I_AHB1_PLL6_DIV_SET(reg, pre_div); + writel(reg, ahb1->reg); + + spin_unlock_irqrestore(&clk_lock, flags); + + return 0; +} + +static const struct clk_ops sun6i_ahb1_clk_ops = { + .determine_rate = sun6i_ahb1_clk_determine_rate, + .recalc_rate = sun6i_ahb1_clk_recalc_rate, + .set_rate = sun6i_ahb1_clk_set_rate, +}; + +static void __init sun6i_ahb1_clk_setup(struct device_node *node) +{ + struct clk *clk; + struct sun6i_ahb1_clk *ahb1; + struct clk_mux *mux; + const char *clk_name = node->name; + const char *parents[SUN6I_AHB1_MAX_PARENTS]; + void __iomem *reg; + int i = 0; + + reg = of_io_request_and_map(node, 0, of_node_full_name(node)); + + /* we have a mux, we will have >1 parents */ + while (i < SUN6I_AHB1_MAX_PARENTS && + (parents[i] = of_clk_get_parent_name(node, i)) != NULL) + i++; + + of_property_read_string(node, "clock-output-names", &clk_name); + + ahb1 = kzalloc(sizeof(struct sun6i_ahb1_clk), GFP_KERNEL); + if (!ahb1) + return; + + mux = kzalloc(sizeof(struct clk_mux), GFP_KERNEL); + if (!mux) { + kfree(ahb1); + return; + } + + /* set up clock properties */ + mux->reg = reg; + mux->shift = SUN6I_AHB1_MUX_SHIFT; + mux->mask = SUN6I_AHB1_MUX_MASK; + mux->lock = &clk_lock; + ahb1->reg = reg; + + clk = clk_register_composite(NULL, clk_name, parents, i, + &mux->hw, &clk_mux_ops, + &ahb1->hw, &sun6i_ahb1_clk_ops, + NULL, NULL, 0); + + if (!IS_ERR(clk)) { + of_clk_add_provider(node, of_clk_src_simple_get, clk); + clk_register_clkdev(clk, clk_name, NULL); + } +} +CLK_OF_DECLARE(sun6i_a31_ahb1, "allwinner,sun6i-a31-ahb1-clk", sun6i_ahb1_clk_setup); + /* Maximum number of parents our clocks have */ #define SUNXI_MAX_PARENTS 5 @@ -355,43 +565,6 @@ static void sun7i_a20_get_out_factors(u32 *freq, u32 parent_rate, } /** - * clk_sunxi_mmc_phase_control() - configures MMC clock phase control - */ - -void clk_sunxi_mmc_phase_control(struct clk *clk, u8 sample, u8 output) -{ - #define to_clk_composite(_hw) container_of(_hw, struct clk_composite, hw) - #define to_clk_factors(_hw) container_of(_hw, struct clk_factors, hw) - - struct clk_hw *hw = __clk_get_hw(clk); - struct clk_composite *composite = to_clk_composite(hw); - struct clk_hw *rate_hw = composite->rate_hw; - struct clk_factors *factors = to_clk_factors(rate_hw); - unsigned long flags = 0; - u32 reg; - - if (factors->lock) - spin_lock_irqsave(factors->lock, flags); - - reg = readl(factors->reg); - - /* set sample clock phase control */ - reg &= ~(0x7 << 20); - reg |= ((sample & 0x7) << 20); - - /* set output clock phase control */ - reg &= ~(0x7 << 8); - reg |= ((output & 0x7) << 8); - - writel(reg, factors->reg); - - if (factors->lock) - spin_unlock_irqrestore(factors->lock, flags); -} -EXPORT_SYMBOL(clk_sunxi_mmc_phase_control); - - -/** * sunxi_factors_clk_setup() - Setup function for factor clocks */ @@ -413,6 +586,7 @@ static struct clk_factors_config sun6i_a31_pll1_config = { .kwidth = 2, .mshift = 0, .mwidth = 2, + .n_start = 1, }; static struct clk_factors_config sun8i_a23_pll1_config = { @@ -520,7 +694,16 @@ static const struct factors_data sun7i_a20_out_data __initconst = { static struct clk * __init sunxi_factors_clk_setup(struct device_node *node, const struct factors_data *data) { - return sunxi_factors_register(node, data, &clk_lock); + void __iomem *reg; + + reg = of_iomap(node, 0); + if (!reg) { + pr_err("Could not get registers for factors-clk: %s\n", + node->name); + return NULL; + } + + return sunxi_factors_register(node, data, &clk_lock, reg); } @@ -561,7 +744,7 @@ static void __init sunxi_mux_clk_setup(struct device_node *node, of_property_read_string(node, "clock-output-names", &clk_name); clk = clk_register_mux(NULL, clk_name, parents, i, - CLK_SET_RATE_NO_REPARENT, reg, + CLK_SET_RATE_PARENT, reg, data->shift, SUNXI_MUX_GATE_WIDTH, 0, &clk_lock); @@ -1217,7 +1400,6 @@ CLK_OF_DECLARE(sun7i_a20_clk_init, "allwinner,sun7i-a20", sun5i_init_clocks); static const char *sun6i_critical_clocks[] __initdata = { "cpu", - "ahb1_sdram", }; static void __init sun6i_init_clocks(struct device_node *node) |