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 int sun6i_ahb1_clk_determine_rate(struct clk_hw *hw,
- struct clk_rate_request *req)
-{
- struct clk_hw *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_hw_get_num_parents(hw);
- for (i = 0; i < num_parents; i++) {
- parent = clk_hw_get_parent_by_index(hw, i);
- if (!parent)
- continue;
- if (clk_hw_get_flags(hw) & CLK_SET_RATE_PARENT)
- parent_rate = clk_hw_round_rate(parent, req->rate);
- else
- parent_rate = clk_hw_get_rate(parent);
-
- child_rate = sun6i_ahb1_clk_round(req->rate, NULL, NULL, i,
- parent_rate);
-
- if (child_rate <= req->rate && child_rate > best_child_rate) {
- best_parent = parent;
- best = parent_rate;
- best_child_rate = child_rate;
- }
- }
-
- if (!best_parent)
- return -EINVAL;
-
- req->best_parent_hw = best_parent;
- req->best_parent_rate = best;
- req->rate = best_child_rate;
-
- return 0;
-}
-
-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;
-
- reg = of_io_request_and_map(node, 0, of_node_full_name(node));
- if (IS_ERR(reg))
- return;
-
- /* we have a mux, we will have >1 parents */
- i = of_clk_parent_fill(node, parents, SUN6I_AHB1_MAX_PARENTS);
- 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
req->p = div;
}
+#define SUN6I_AHB1_PARENT_PLL6 3
+
+/**
+ * sun6i_a31_get_ahb_factors() - calculates m, p factors for AHB
+ * AHB rate is calculated as follows
+ * rate = parent_rate >> p
+ *
+ * if parent is pll6, then
+ * parent_rate = pll6 rate / (m + 1)
+ */
+
+static void sun6i_get_ahb1_factors(struct factors_request *req)
+{
+ u8 div, calcp, calcm = 1;
+
+ /*
+ * clock can only divide, so we will never be able to achieve
+ * frequencies higher than the parent frequency
+ */
+ if (req->parent_rate && req->rate > req->parent_rate)
+ req->rate = req->parent_rate;
+
+ div = DIV_ROUND_UP(req->parent_rate, req->rate);
+
+ /* calculate pre-divider if parent is pll6 */
+ if (req->parent_index == SUN6I_AHB1_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;
+ }
+
+ req->rate = (req->parent_rate / calcm) >> calcp;
+ req->p = calcp;
+ req->m = calcm - 1;
+}
+
+/**
+ * sun6i_ahb1_recalc() - calculates AHB clock rate from m, p factors and
+ * parent index
+ */
+static void sun6i_ahb1_recalc(struct factors_request *req)
+{
+ req->rate = req->parent_rate;
+
+ /* apply pre-divider first if parent is pll6 */
+ if (req->parent_index == SUN6I_AHB1_PARENT_PLL6)
+ req->rate /= req->m + 1;
+
+ /* clk divider */
+ req->rate >>= req->p;
+}
+
/**
* sun4i_get_apb1_factors() - calculates m, p factors for APB1
* APB1 rate is calculated as follows
.pwidth = 2,
};
+static const struct clk_factors_config sun6i_ahb1_config = {
+ .mshift = 6,
+ .mwidth = 2,
+ .pshift = 4,
+ .pwidth = 2,
+};
+
static const struct clk_factors_config sun4i_apb1_config = {
.mshift = 0,
.mwidth = 5,
.getter = sun5i_a13_get_ahb_factors,
};
+static const struct factors_data sun6i_ahb1_data __initconst = {
+ .mux = 12,
+ .muxmask = BIT(1) | BIT(0),
+ .table = &sun6i_ahb1_config,
+ .getter = sun6i_get_ahb1_factors,
+ .recalc = sun6i_ahb1_recalc,
+};
+
static const struct factors_data sun4i_apb1_data __initconst = {
.mux = 24,
.muxmask = BIT(1) | BIT(0),
return sunxi_factors_register(node, data, &clk_lock, reg);
}
+static void __init sun6i_ahb1_clk_setup(struct device_node *node)
+{
+ sunxi_factors_clk_setup(node, &sun6i_ahb1_data);
+}
+CLK_OF_DECLARE(sun6i_a31_ahb1, "allwinner,sun6i-a31-ahb1-clk",
+ sun6i_ahb1_clk_setup);
/**
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