clk: socfpga: agilex: add clock driver for eASIC N5X platform

Add support for Intel's eASIC N5X platform. The clock manager driver for
the N5X is very similar to the Agilex platform, we can re-use most of
the Agilex clock driver.

This patch makes the necessary changes for the driver to differentiate
between the Agilex and the N5X platforms.

Signed-off-by: Dinh Nguyen <dinguyen@kernel.org>
Link: https://lore.kernel.org/r/20210212143059.478554-2-dinguyen@kernel.org
Signed-off-by: Stephen Boyd <sboyd@kernel.org>

1 files changed, 53 insertions, 0 deletions

diff --git a/drivers/clk/socfpga/clk-periph-s10.c b/drivers/clk/socfpga/clk-periph-s10.c
index 397b77b89b16..0ff2b9d24035 100644
--- a/drivers/clk/socfpga/clk-periph-s10.c
+++ b/drivers/clk/socfpga/clk-periph-s10.c
@@ -15,6 +15,21 @@
 
 #define to_periph_clk(p) container_of(p, struct socfpga_periph_clk, hw.hw)
 
+static unsigned long n5x_clk_peri_c_clk_recalc_rate(struct clk_hw *hwclk,
+					     unsigned long parent_rate)
+{
+	struct socfpga_periph_clk *socfpgaclk = to_periph_clk(hwclk);
+	unsigned long div;
+	unsigned long shift = socfpgaclk->shift;
+	u32 val;
+
+	val = readl(socfpgaclk->hw.reg);
+	val &= (0x1f << shift);
+	div = (val >> shift) + 1;
+
+	return parent_rate / div;
+}
+
 static unsigned long clk_peri_c_clk_recalc_rate(struct clk_hw *hwclk,
 					     unsigned long parent_rate)
 {
@@ -63,6 +78,11 @@ static u8 clk_periclk_get_parent(struct clk_hw *hwclk)
 	return parent;
 }
 
+static const struct clk_ops n5x_peri_c_clk_ops = {
+	.recalc_rate = n5x_clk_peri_c_clk_recalc_rate,
+	.get_parent = clk_periclk_get_parent,
+};
+
 static const struct clk_ops peri_c_clk_ops = {
 	.recalc_rate = clk_peri_c_clk_recalc_rate,
 	.get_parent = clk_periclk_get_parent,
@@ -107,6 +127,39 @@ struct clk *s10_register_periph(const struct stratix10_perip_c_clock *clks,
 	return clk;
 }
 
+struct clk *n5x_register_periph(const struct n5x_perip_c_clock *clks,
+				void __iomem *regbase)
+{
+	struct clk *clk;
+	struct socfpga_periph_clk *periph_clk;
+	struct clk_init_data init;
+	const char *name = clks->name;
+	const char *parent_name = clks->parent_name;
+
+	periph_clk = kzalloc(sizeof(*periph_clk), GFP_KERNEL);
+	if (WARN_ON(!periph_clk))
+		return NULL;
+
+	periph_clk->hw.reg = regbase + clks->offset;
+	periph_clk->shift = clks->shift;
+
+	init.name = name;
+	init.ops = &n5x_peri_c_clk_ops;
+	init.flags = clks->flags;
+
+	init.num_parents = clks->num_parents;
+	init.parent_names = parent_name ? &parent_name : NULL;
+
+	periph_clk->hw.hw.init = &init;
+
+	clk = clk_register(NULL, &periph_clk->hw.hw);
+	if (WARN_ON(IS_ERR(clk))) {
+		kfree(periph_clk);
+		return NULL;
+	}
+	return clk;
+}
+
 struct clk *s10_register_cnt_periph(const struct stratix10_perip_cnt_clock *clks,
 				    void __iomem *regbase)
 {