X-Git-Url: https://gerrit.opnfv.org/gerrit/gitweb?a=blobdiff_plain;f=kernel%2Fdrivers%2Fclk%2Fh8300%2Fclk-h8s2678.c;fp=kernel%2Fdrivers%2Fclk%2Fh8300%2Fclk-h8s2678.c;h=6cf38dc1c9291e843f140e187b5dd0f0aadf6d4b;hb=e09b41010ba33a20a87472ee821fa407a5b8da36;hp=0000000000000000000000000000000000000000;hpb=f93b97fd65072de626c074dbe099a1fff05ce060;p=kvmfornfv.git

diff --git a/kernel/drivers/clk/h8300/clk-h8s2678.c b/kernel/drivers/clk/h8300/clk-h8s2678.c
new file mode 100644
index 000000000..6cf38dc1c
--- /dev/null
+++ b/kernel/drivers/clk/h8300/clk-h8s2678.c
@@ -0,0 +1,143 @@
+/*
+ * H8S2678 clock driver
+ *
+ * Copyright 2015 Yoshinori Sato <ysato@users.sourceforge.jp>
+ */
+
+#include <linux/clk-provider.h>
+#include <linux/err.h>
+#include <linux/device.h>
+#include <linux/of_address.h>
+#include <linux/slab.h>
+
+static DEFINE_SPINLOCK(clklock);
+
+#define MAX_FREQ 33333333
+#define MIN_FREQ  8000000
+
+struct pll_clock {
+	struct clk_hw hw;
+	void __iomem *sckcr;
+	void __iomem *pllcr;
+};
+
+#define to_pll_clock(_hw) container_of(_hw, struct pll_clock, hw)
+
+static unsigned long pll_recalc_rate(struct clk_hw *hw,
+		unsigned long parent_rate)
+{
+	struct pll_clock *pll_clock = to_pll_clock(hw);
+	int mul = 1 << (readb(pll_clock->pllcr) & 3);
+
+	return parent_rate * mul;
+}
+
+static long pll_round_rate(struct clk_hw *hw, unsigned long rate,
+				unsigned long *prate)
+{
+	int i, m = -1;
+	long offset[3];
+
+	if (rate > MAX_FREQ)
+		rate = MAX_FREQ;
+	if (rate < MIN_FREQ)
+		rate = MIN_FREQ;
+
+	for (i = 0; i < 3; i++)
+		offset[i] = abs(rate - (*prate * (1 << i)));
+	for (i = 0; i < 3; i++)
+		if (m < 0)
+			m = i;
+		else
+			m = (offset[i] < offset[m])?i:m;
+
+	return *prate * (1 << m);
+}
+
+static int pll_set_rate(struct clk_hw *hw, unsigned long rate,
+			unsigned long parent_rate)
+{
+	int pll;
+	unsigned char val;
+	unsigned long flags;
+	struct pll_clock *pll_clock = to_pll_clock(hw);
+
+	pll = ((rate / parent_rate) / 2) & 0x03;
+	spin_lock_irqsave(&clklock, flags);
+	val = readb(pll_clock->sckcr);
+	val |= 0x08;
+	writeb(val, pll_clock->sckcr);
+	val = readb(pll_clock->pllcr);
+	val &= ~0x03;
+	val |= pll;
+	writeb(val, pll_clock->pllcr);
+	spin_unlock_irqrestore(&clklock, flags);
+	return 0;
+}
+
+static const struct clk_ops pll_ops = {
+	.recalc_rate = pll_recalc_rate,
+	.round_rate = pll_round_rate,
+	.set_rate = pll_set_rate,
+};
+
+static void __init h8s2678_pll_clk_setup(struct device_node *node)
+{
+	int num_parents;
+	struct clk *clk;
+	const char *clk_name = node->name;
+	const char *parent_name;
+	struct pll_clock *pll_clock;
+	struct clk_init_data init;
+
+	num_parents = of_clk_get_parent_count(node);
+	if (num_parents < 1) {
+		pr_err("%s: no parent found", clk_name);
+		return;
+	}
+
+
+	pll_clock = kzalloc(sizeof(*pll_clock), GFP_KERNEL);
+	if (!pll_clock)
+		return;
+
+	pll_clock->sckcr = of_iomap(node, 0);
+	if (pll_clock->sckcr == NULL) {
+		pr_err("%s: failed to map divide register", clk_name);
+		goto free_clock;
+	}
+
+	pll_clock->pllcr = of_iomap(node, 1);
+	if (pll_clock->pllcr == NULL) {
+		pr_err("%s: failed to map multiply register", clk_name);
+		goto unmap_sckcr;
+	}
+
+	parent_name = of_clk_get_parent_name(node, 0);
+	init.name = clk_name;
+	init.ops = &pll_ops;
+	init.flags = CLK_IS_BASIC;
+	init.parent_names = &parent_name;
+	init.num_parents = 1;
+	pll_clock->hw.init = &init;
+
+	clk = clk_register(NULL, &pll_clock->hw);
+	if (IS_ERR(clk)) {
+		pr_err("%s: failed to register %s div clock (%ld)\n",
+		       __func__, clk_name, PTR_ERR(clk));
+		goto unmap_pllcr;
+	}
+
+	of_clk_add_provider(node, of_clk_src_simple_get, clk);
+	return;
+
+unmap_pllcr:
+	iounmap(pll_clock->pllcr);
+unmap_sckcr:
+	iounmap(pll_clock->sckcr);
+free_clock:
+	kfree(pll_clock);
+}
+
+CLK_OF_DECLARE(h8s2678_div_clk, "renesas,h8s2678-pll-clock",
+	       h8s2678_pll_clk_setup);