clk: socfpga: agilex: add clock driver for the Agilex platform

For the most part the Agilex clock structure is very similar to
Stratix10, so we re-use most of the Stratix10 clock driver.

Signed-off-by: Dinh Nguyen <dinguyen@kernel.org>
Link: https://lkml.kernel.org/r/20200512181647.5071-5-dinguyen@kernel.org
Signed-off-by: Stephen Boyd <sboyd@kernel.org>

1 files changed, 68 insertions, 0 deletions

diff --git a/drivers/clk/socfpga/clk-pll-s10.c b/drivers/clk/socfpga/clk-pll-s10.c
index 5c3e1ee44f6b..4e268953b7da 100644
--- a/drivers/clk/socfpga/clk-pll-s10.c
+++ b/drivers/clk/socfpga/clk-pll-s10.c
@@ -18,8 +18,12 @@
 #define SOCFPGA_PLL_RESET_MASK		0x2
 #define SOCFPGA_PLL_REFDIV_MASK		0x00003F00
 #define SOCFPGA_PLL_REFDIV_SHIFT	8
+#define SOCFPGA_PLL_AREFDIV_MASK	0x00000F00
+#define SOCFPGA_PLL_DREFDIV_MASK	0x00003000
+#define SOCFPGA_PLL_DREFDIV_SHIFT	12
 #define SOCFPGA_PLL_MDIV_MASK		0xFF000000
 #define SOCFPGA_PLL_MDIV_SHIFT		24
+#define SOCFPGA_AGILEX_PLL_MDIV_MASK	0x000003FF
 #define SWCTRLBTCLKSEL_MASK		0x200
 #define SWCTRLBTCLKSEL_SHIFT		9
 
@@ -27,6 +31,27 @@
 
 #define to_socfpga_clk(p) container_of(p, struct socfpga_pll, hw.hw)
 
+static unsigned long agilex_clk_pll_recalc_rate(struct clk_hw *hwclk,
+						unsigned long parent_rate)
+{
+	struct socfpga_pll *socfpgaclk = to_socfpga_clk(hwclk);
+	unsigned long arefdiv, reg, mdiv;
+	unsigned long long vco_freq;
+
+	/* read VCO1 reg for numerator and denominator */
+	reg = readl(socfpgaclk->hw.reg);
+	arefdiv = (reg & SOCFPGA_PLL_AREFDIV_MASK) >> SOCFPGA_PLL_REFDIV_SHIFT;
+
+	vco_freq = (unsigned long long)parent_rate / arefdiv;
+
+	/* Read mdiv and fdiv from the fdbck register */
+	reg = readl(socfpgaclk->hw.reg + 0x24);
+	mdiv = reg & SOCFPGA_AGILEX_PLL_MDIV_MASK;
+
+	vco_freq = (unsigned long long)vco_freq * mdiv;
+	return (unsigned long)vco_freq;
+}
+
 static unsigned long clk_pll_recalc_rate(struct clk_hw *hwclk,
 					 unsigned long parent_rate)
 {
@@ -98,6 +123,12 @@ static int clk_pll_prepare(struct clk_hw *hwclk)
 	return 0;
 }
 
+static const struct clk_ops agilex_clk_pll_ops = {
+	.recalc_rate = agilex_clk_pll_recalc_rate,
+	.get_parent = clk_pll_get_parent,
+	.prepare = clk_pll_prepare,
+};
+
 static const struct clk_ops clk_pll_ops = {
 	.recalc_rate = clk_pll_recalc_rate,
 	.get_parent = clk_pll_get_parent,
@@ -146,3 +177,40 @@ struct clk *s10_register_pll(const struct stratix10_pll_clock *clks,
 	}
 	return clk;
 }
+
+struct clk *agilex_register_pll(const struct stratix10_pll_clock *clks,
+				void __iomem *reg)
+{
+	struct clk *clk;
+	struct socfpga_pll *pll_clk;
+	struct clk_init_data init;
+	const char *name = clks->name;
+
+	pll_clk = kzalloc(sizeof(*pll_clk), GFP_KERNEL);
+	if (WARN_ON(!pll_clk))
+		return NULL;
+
+	pll_clk->hw.reg = reg + clks->offset;
+
+	if (streq(name, SOCFPGA_BOOT_CLK))
+		init.ops = &clk_boot_ops;
+	else
+		init.ops = &agilex_clk_pll_ops;
+
+	init.name = name;
+	init.flags = clks->flags;
+
+	init.num_parents = clks->num_parents;
+	init.parent_names = NULL;
+	init.parent_data = clks->parent_data;
+	pll_clk->hw.hw.init = &init;
+
+	pll_clk->hw.bit_idx = SOCFPGA_PLL_POWER;
+
+	clk = clk_register(NULL, &pll_clk->hw.hw);
+	if (WARN_ON(IS_ERR(clk))) {
+		kfree(pll_clk);
+		return NULL;
+	}
+	return clk;
+}