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@@ -0,0 +1,147 @@
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+/*
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+ * H8S2678 clock driver
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+ *
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+ * Copyright 2015 Yoshinori Sato <ysato@users.sourceforge.jp>
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+ */
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+
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+#include <linux/clk.h>
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+#include <linux/clkdev.h>
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+#include <linux/clk-provider.h>
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+#include <linux/err.h>
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+#include <linux/device.h>
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+#include <linux/of_address.h>
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+
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+static DEFINE_SPINLOCK(clklock);
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+
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+#define MAX_FREQ 33333333
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+#define MIN_FREQ 8000000
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+
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+struct pll_clock {
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+ struct clk_hw hw;
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+ void __iomem *sckcr;
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+ void __iomem *pllcr;
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+};
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+
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+#define to_pll_clock(_hw) container_of(_hw, struct pll_clock, hw)
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+
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+static unsigned long pll_recalc_rate(struct clk_hw *hw,
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+ unsigned long parent_rate)
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+{
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+ struct pll_clock *pll_clock = to_pll_clock(hw);
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+ int mul = 1 << (ctrl_inb((unsigned long)pll_clock->pllcr) & 3);
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+
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+ return parent_rate * mul;
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+}
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+
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+static long pll_round_rate(struct clk_hw *hw, unsigned long rate,
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+ unsigned long *prate)
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+{
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+ int i, m = -1;
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+ long offset[3];
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+
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+ if (rate > MAX_FREQ)
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+ rate = MAX_FREQ;
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+ if (rate < MIN_FREQ)
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+ rate = MIN_FREQ;
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+
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+ for (i = 0; i < 3; i++)
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+ offset[i] = abs(rate - (*prate * (1 << i)));
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+ for (i = 0; i < 3; i++)
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+ if (m < 0)
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+ m = i;
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+ else
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+ m = (offset[i] < offset[m])?i:m;
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+
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+ return *prate * (1 << m);
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+}
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+
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+static int pll_set_rate(struct clk_hw *hw, unsigned long rate,
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+ unsigned long parent_rate)
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+{
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+ int pll;
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+ unsigned char val;
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+ unsigned long flags;
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+ struct pll_clock *pll_clock = to_pll_clock(hw);
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+
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+ pll = ((rate / parent_rate) / 2) & 0x03;
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+ spin_lock_irqsave(&clklock, flags);
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+ val = ctrl_inb((unsigned long)pll_clock->sckcr);
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+ val |= 0x08;
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+ ctrl_outb(val, (unsigned long)pll_clock->sckcr);
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+ val = ctrl_inb((unsigned long)pll_clock->pllcr);
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+ val &= ~0x03;
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+ val |= pll;
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+ ctrl_outb(val, (unsigned long)pll_clock->pllcr);
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+ spin_unlock_irqrestore(&clklock, flags);
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+ return 0;
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+}
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+
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+static const struct clk_ops pll_ops = {
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+ .recalc_rate = pll_recalc_rate,
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+ .round_rate = pll_round_rate,
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+ .set_rate = pll_set_rate,
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+};
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+
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+static void __init h8s2678_pll_clk_setup(struct device_node *node)
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+{
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+ unsigned int num_parents;
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+ struct clk *clk;
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+ const char *clk_name = node->name;
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+ const char *parent_name;
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+ struct pll_clock *pll_clock;
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+ struct clk_init_data init;
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+
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+ num_parents = of_clk_get_parent_count(node);
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+ if (num_parents < 1) {
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+ pr_err("%s: no parent found", clk_name);
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+ return;
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+ }
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+
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+
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+ pll_clock = kzalloc(sizeof(struct pll_clock), GFP_KERNEL);
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+ if (!pll_clock) {
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+ pr_err("%s: failed to alloc memory", clk_name);
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+ return;
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+ }
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+
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+ pll_clock->sckcr = of_iomap(node, 0);
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+ if (pll_clock->sckcr == NULL) {
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+ pr_err("%s: failed to map divide register", clk_name);
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+ goto error;
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+ }
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+
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+ pll_clock->pllcr = of_iomap(node, 1);
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+ if (pll_clock->pllcr == NULL) {
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+ pr_err("%s: failed to map multiply register", clk_name);
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+ goto error;
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+ }
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+
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+ parent_name = of_clk_get_parent_name(node, 0);
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+ init.name = clk_name;
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+ init.ops = &pll_ops;
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+ init.flags = CLK_IS_BASIC;
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+ init.parent_names = &parent_name;
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+ init.num_parents = 1;
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+ pll_clock->hw.init = &init;
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+
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+ clk = clk_register(NULL, &pll_clock->hw);
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+ if (IS_ERR(clk))
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+ kfree(pll_clock);
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+ if (!IS_ERR(clk)) {
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+ of_clk_add_provider(node, of_clk_src_simple_get, clk);
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+ return;
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+ }
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+ pr_err("%s: failed to register %s div clock (%ld)\n",
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+ __func__, clk_name, PTR_ERR(clk));
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+error:
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+ if (pll_clock) {
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+ if (pll_clock->sckcr)
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+ iounmap(pll_clock->sckcr);
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+ if (pll_clock->pllcr)
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+ iounmap(pll_clock->pllcr);
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+ kfree(pll_clock);
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+ }
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+}
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+
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+CLK_OF_DECLARE(h8s2678_div_clk, "renesas,h8s2678-pll-clock",
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+ h8s2678_pll_clk_setup);
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