1 files changed, 305 insertions, 0 deletions
diff --git a/drivers/clk/renesas/rcar-gen4-cpg.c b/drivers/clk/renesas/rcar-gen4-cpg.c
new file mode 100644
index 000000000000..54ebf4b3c128
--- /dev/null
+++ b/drivers/clk/renesas/rcar-gen4-cpg.c
@@ -0,0 +1,305 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * R-Car Gen4 Clock Pulse Generator
+ *
+ * Copyright (C) 2021 Renesas Electronics Corp.
+ *
+ * Based on rcar-gen3-cpg.c
+ *
+ * Copyright (C) 2015-2018 Glider bvba
+ * Copyright (C) 2019 Renesas Electronics Corp.
+ */
+
+#include <linux/bitfield.h>
+#include <linux/clk.h>
+#include <linux/clk-provider.h>
+#include <linux/device.h>
+#include <linux/err.h>
+#include <linux/init.h>
+#include <linux/io.h>
+#include <linux/slab.h>
+
+#include "renesas-cpg-mssr.h"
+#include "rcar-gen4-cpg.h"
+#include "rcar-cpg-lib.h"
+
+static const struct rcar_gen4_cpg_pll_config *cpg_pll_config __initconst;
+static unsigned int cpg_clk_extalr __initdata;
+static u32 cpg_mode __initdata;
+
+/*
+ * Z0 Clock & Z1 Clock
+ */
+#define CPG_FRQCRB			0x00000804
+#define CPG_FRQCRB_KICK			BIT(31)
+#define CPG_FRQCRC			0x00000808
+
+struct cpg_z_clk {
+	struct clk_hw hw;
+	void __iomem *reg;
+	void __iomem *kick_reg;
+	unsigned long max_rate;		/* Maximum rate for normal mode */
+	unsigned int fixed_div;
+	u32 mask;
+};
+
+#define to_z_clk(_hw)	container_of(_hw, struct cpg_z_clk, hw)
+
+static unsigned long cpg_z_clk_recalc_rate(struct clk_hw *hw,
+					   unsigned long parent_rate)
+{
+	struct cpg_z_clk *zclk = to_z_clk(hw);
+	unsigned int mult;
+	u32 val;
+
+	val = readl(zclk->reg) & zclk->mask;
+	mult = 32 - (val >> __ffs(zclk->mask));
+
+	return DIV_ROUND_CLOSEST_ULL((u64)parent_rate * mult,
+				     32 * zclk->fixed_div);
+}
+
+static int cpg_z_clk_determine_rate(struct clk_hw *hw,
+				    struct clk_rate_request *req)
+{
+	struct cpg_z_clk *zclk = to_z_clk(hw);
+	unsigned int min_mult, max_mult, mult;
+	unsigned long rate, prate;
+
+	rate = min(req->rate, req->max_rate);
+	if (rate <= zclk->max_rate) {
+		/* Set parent rate to initial value for normal modes */
+		prate = zclk->max_rate;
+	} else {
+		/* Set increased parent rate for boost modes */
+		prate = rate;
+	}
+	req->best_parent_rate = clk_hw_round_rate(clk_hw_get_parent(hw),
+						  prate * zclk->fixed_div);
+
+	prate = req->best_parent_rate / zclk->fixed_div;
+	min_mult = max(div64_ul(req->min_rate * 32ULL, prate), 1ULL);
+	max_mult = min(div64_ul(req->max_rate * 32ULL, prate), 32ULL);
+	if (max_mult < min_mult)
+		return -EINVAL;
+
+	mult = DIV_ROUND_CLOSEST_ULL(rate * 32ULL, prate);
+	mult = clamp(mult, min_mult, max_mult);
+
+	req->rate = DIV_ROUND_CLOSEST_ULL((u64)prate * mult, 32);
+	return 0;
+}
+
+static int cpg_z_clk_set_rate(struct clk_hw *hw, unsigned long rate,
+			      unsigned long parent_rate)
+{
+	struct cpg_z_clk *zclk = to_z_clk(hw);
+	unsigned int mult;
+	unsigned int i;
+
+	mult = DIV64_U64_ROUND_CLOSEST(rate * 32ULL * zclk->fixed_div,
+				       parent_rate);
+	mult = clamp(mult, 1U, 32U);
+
+	if (readl(zclk->kick_reg) & CPG_FRQCRB_KICK)
+		return -EBUSY;
+
+	cpg_reg_modify(zclk->reg, zclk->mask, (32 - mult) << __ffs(zclk->mask));
+
+	/*
+	 * Set KICK bit in FRQCRB to update hardware setting and wait for
+	 * clock change completion.
+	 */
+	cpg_reg_modify(zclk->kick_reg, 0, CPG_FRQCRB_KICK);
+
+	/*
+	 * Note: There is no HW information about the worst case latency.
+	 *
+	 * Using experimental measurements, it seems that no more than
+	 * ~10 iterations are needed, independently of the CPU rate.
+	 * Since this value might be dependent on external xtal rate, pll1
+	 * rate or even the other emulation clocks rate, use 1000 as a
+	 * "super" safe value.
+	 */
+	for (i = 1000; i; i--) {
+		if (!(readl(zclk->kick_reg) & CPG_FRQCRB_KICK))
+			return 0;
+
+		cpu_relax();
+	}
+
+	return -ETIMEDOUT;
+}
+
+static const struct clk_ops cpg_z_clk_ops = {
+	.recalc_rate = cpg_z_clk_recalc_rate,
+	.determine_rate = cpg_z_clk_determine_rate,
+	.set_rate = cpg_z_clk_set_rate,
+};
+
+static struct clk * __init cpg_z_clk_register(const char *name,
+					      const char *parent_name,
+					      void __iomem *reg,
+					      unsigned int div,
+					      unsigned int offset)
+{
+	struct clk_init_data init = {};
+	struct cpg_z_clk *zclk;
+	struct clk *clk;
+
+	zclk = kzalloc(sizeof(*zclk), GFP_KERNEL);
+	if (!zclk)
+		return ERR_PTR(-ENOMEM);
+
+	init.name = name;
+	init.ops = &cpg_z_clk_ops;
+	init.flags = CLK_SET_RATE_PARENT;
+	init.parent_names = &parent_name;
+	init.num_parents = 1;
+
+	zclk->reg = reg + CPG_FRQCRC;
+	zclk->kick_reg = reg + CPG_FRQCRB;
+	zclk->hw.init = &init;
+	zclk->mask = GENMASK(offset + 4, offset);
+	zclk->fixed_div = div; /* PLLVCO x 1/div x SYS-CPU divider */
+
+	clk = clk_register(NULL, &zclk->hw);
+	if (IS_ERR(clk)) {
+		kfree(zclk);
+		return clk;
+	}
+
+	zclk->max_rate = clk_hw_get_rate(clk_hw_get_parent(&zclk->hw)) /
+			 zclk->fixed_div;
+	return clk;
+}
+
+/*
+ * RPC Clocks
+ */
+static const struct clk_div_table cpg_rpcsrc_div_table[] = {
+	{ 0, 4 }, { 1, 6 }, { 2, 5 }, { 3, 6 }, { 0, 0 },
+};
+
+struct clk * __init rcar_gen4_cpg_clk_register(struct device *dev,
+	const struct cpg_core_clk *core, const struct cpg_mssr_info *info,
+	struct clk **clks, void __iomem *base,
+	struct raw_notifier_head *notifiers)
+{
+	const struct clk *parent;
+	unsigned int mult = 1;
+	unsigned int div = 1;
+	u32 value;
+
+	parent = clks[core->parent & 0xffff];	/* some types use high bits */
+	if (IS_ERR(parent))
+		return ERR_CAST(parent);
+
+	switch (core->type) {
+	case CLK_TYPE_GEN4_MAIN:
+		div = cpg_pll_config->extal_div;
+		break;
+
+	case CLK_TYPE_GEN4_PLL1:
+		mult = cpg_pll_config->pll1_mult;
+		div = cpg_pll_config->pll1_div;
+		break;
+
+	case CLK_TYPE_GEN4_PLL2:
+		mult = cpg_pll_config->pll2_mult;
+		div = cpg_pll_config->pll2_div;
+		break;
+
+	case CLK_TYPE_GEN4_PLL3:
+		mult = cpg_pll_config->pll3_mult;
+		div = cpg_pll_config->pll3_div;
+		break;
+
+	case CLK_TYPE_GEN4_PLL5:
+		mult = cpg_pll_config->pll5_mult;
+		div = cpg_pll_config->pll5_div;
+		break;
+
+	case CLK_TYPE_GEN4_PLL6:
+		mult = cpg_pll_config->pll6_mult;
+		div = cpg_pll_config->pll6_div;
+		break;
+
+	case CLK_TYPE_GEN4_PLL2X_3X:
+		value = readl(base + core->offset);
+		mult = (((value >> 24) & 0x7f) + 1) * 2;
+		break;
+
+	case CLK_TYPE_GEN4_Z:
+		return cpg_z_clk_register(core->name, __clk_get_name(parent),
+					  base, core->div, core->offset);
+
+	case CLK_TYPE_GEN4_SDSRC:
+		div = ((readl(base + SD0CKCR1) >> 29) & 0x03) + 4;
+		break;
+
+	case CLK_TYPE_GEN4_SDH:
+		return cpg_sdh_clk_register(core->name, base + core->offset,
+					   __clk_get_name(parent), notifiers);
+
+	case CLK_TYPE_GEN4_SD:
+		return cpg_sd_clk_register(core->name, base + core->offset,
+					   __clk_get_name(parent));
+
+	case CLK_TYPE_GEN4_MDSEL:
+		/*
+		 * Clock selectable between two parents and two fixed dividers
+		 * using a mode pin
+		 */
+		if (cpg_mode & BIT(core->offset)) {
+			div = core->div & 0xffff;
+		} else {
+			parent = clks[core->parent >> 16];
+			if (IS_ERR(parent))
+				return ERR_CAST(parent);
+			div = core->div >> 16;
+		}
+		mult = 1;
+		break;
+
+	case CLK_TYPE_GEN4_OSC:
+		/*
+		 * Clock combining OSC EXTAL predivider and a fixed divider
+		 */
+		div = cpg_pll_config->osc_prediv * core->div;
+		break;
+
+	case CLK_TYPE_GEN4_RPCSRC:
+		return clk_register_divider_table(NULL, core->name,
+						  __clk_get_name(parent), 0,
+						  base + CPG_RPCCKCR, 3, 2, 0,
+						  cpg_rpcsrc_div_table,
+						  &cpg_lock);
+
+	case CLK_TYPE_GEN4_RPC:
+		return cpg_rpc_clk_register(core->name, base + CPG_RPCCKCR,
+					    __clk_get_name(parent), notifiers);
+
+	case CLK_TYPE_GEN4_RPCD2:
+		return cpg_rpcd2_clk_register(core->name, base + CPG_RPCCKCR,
+					      __clk_get_name(parent));
+
+	default:
+		return ERR_PTR(-EINVAL);
+	}
+
+	return clk_register_fixed_factor(NULL, core->name,
+					 __clk_get_name(parent), 0, mult, div);
+}
+
+int __init rcar_gen4_cpg_init(const struct rcar_gen4_cpg_pll_config *config,
+			      unsigned int clk_extalr, u32 mode)
+{
+	cpg_pll_config = config;
+	cpg_clk_extalr = clk_extalr;
+	cpg_mode = mode;
+
+	spin_lock_init(&cpg_lock);
+
+	return 0;
+}