Add the common R-Car Gen2 (and RZ/G) Clock Pulse Generator / Module Standby
and Software Reset support code, using the CPG/MSSR driver core.
Based on the proof-of-concept R8A7791 CPG/MSSR patch by Geert Uytterhoeven
<geert+renesas@xxxxxxxxx>.
Signed-off-by: Sergei Shtylyov <sergei.shtylyov@xxxxxxxxxxxxxxxxxx>
Reviewed-by: Geert Uytterhoeven <geert+renesas@xxxxxxxxx>
---
Changes in version 3:
- remove the divisor logic from the PLL0 related code;
- also mention R-Car V2H as not having the PLL0CR register.
Changes in version 2:
- added support for non-existing PLL0CR;
- removed the function reading the mode pins;
- added/used the #define's for PLL0CR.STC;
- used CPG_FRQCRC_ZFC_SHIFT to #define CPG_FRQCRC_ZFC_MASK;
- removed rcar_gen2_read_modemr();
- added Geert's tag.
drivers/clk/renesas/rcar-gen2-cpg.c | 366 ++++++++++++++++++++++++++++++++++++
drivers/clk/renesas/rcar-gen2-cpg.h | 42 ++++
2 files changed, 408 insertions(+)
Index: renesas/drivers/clk/renesas/rcar-gen2-cpg.c
===================================================================
--- /dev/null
+++ renesas/drivers/clk/renesas/rcar-gen2-cpg.c
@@ -0,0 +1,366 @@
+/*
+ * R-Car Gen2 Clock Pulse Generator
+ *
+ * Copyright (C) 2016 Cogent Embedded Inc.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published
+ * by the Free Software Foundation.
+ */
+
+#include <linux/bug.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-gen2-cpg.h"
+
+#define CPG_FRQCRB 0x0004
+#define CPG_FRQCRB_KICK BIT(31)
+#define CPG_SDCKCR 0x0074
+#define CPG_PLL0CR 0x00d8
+#define CPG_PLL0CR_STC_SHIFT 24
+#define CPG_PLL0CR_STC_MASK (0x7f << CPG_PLL0CR_STC_SHIFT)
+#define CPG_FRQCRC 0x00e0
+#define CPG_FRQCRC_ZFC_SHIFT 8
+#define CPG_FRQCRC_ZFC_MASK (0x1f << CPG_FRQCRC_ZFC_SHIFT)
+#define CPG_ADSPCKCR 0x025c
+#define CPG_RCANCKCR 0x0270
+
+static spinlock_t cpg_lock;
+
+/*
+ * Z Clock
+ *
+ * Traits of this clock:
+ * prepare - clk_prepare only ensures that parents are prepared
+ * enable - clk_enable only ensures that parents are enabled
+ * rate - rate is adjustable. clk->rate = parent->rate * mult / 32
+ * parent - fixed parent. No clk_set_parent support
+ */
+
+struct cpg_z_clk {
+ struct clk_hw hw;
+ void __iomem *reg;
+ void __iomem *kick_reg;
+};
+
+#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;
+ unsigned int val;
+
+ val = (readl(zclk->reg) & CPG_FRQCRC_ZFC_MASK) >> CPG_FRQCRC_ZFC_SHIFT;
+ mult = 32 - val;
+
+ return div_u64((u64)parent_rate * mult, 32);
+}
+
+static long cpg_z_clk_round_rate(struct clk_hw *hw, unsigned long rate,
+ unsigned long *parent_rate)
+{
+ unsigned long prate = *parent_rate;
+ unsigned int mult;
+
+ if (!prate)
+ prate = 1;
+
+ mult = div_u64((u64)rate * 32, prate);
+ mult = clamp(mult, 1U, 32U);
+
+ return *parent_rate / 32 * mult;
+}
+
+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;
+ u32 val, kick;
+ unsigned int i;
+
+ mult = div_u64((u64)rate * 32, parent_rate);
+ mult = clamp(mult, 1U, 32U);
+
+ if (readl(zclk->kick_reg) & CPG_FRQCRB_KICK)
+ return -EBUSY;
+
+ val = readl(zclk->reg);
+ val &= ~CPG_FRQCRC_ZFC_MASK;
+ val |= (32 - mult) << CPG_FRQCRC_ZFC_SHIFT;
+ writel(val, zclk->reg);
+
+ /*
+ * Set KICK bit in FRQCRB to update hardware setting and wait for
+ * clock change completion.
+ */
+ kick = readl(zclk->kick_reg);
+ kick |= CPG_FRQCRB_KICK;
+ writel(kick, zclk->kick_reg);
+
+ /*
+ * 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,
+ .round_rate = cpg_z_clk_round_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 *base)
+{
+ 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 = 0;
+ init.parent_names = &parent_name;
+ init.num_parents = 1;
+
+ zclk->reg = base + CPG_FRQCRC;
+ zclk->kick_reg = base + CPG_FRQCRB;
+ zclk->hw.init = &init;
+
+ clk = clk_register(NULL, &zclk->hw);
+ if (IS_ERR(clk))
+ kfree(zclk);
+
+ return clk;
+}
+
+static struct clk * __init cpg_rcan_clk_register(const char *name,
+ const char *parent_name,
+ void __iomem *base)
+{
+ struct clk_fixed_factor *fixed;
+ struct clk_gate *gate;
+ struct clk *clk;
+
+ fixed = kzalloc(sizeof(*fixed), GFP_KERNEL);
+ if (!fixed)
+ return ERR_PTR(-ENOMEM);
+
+ fixed->mult = 1;
+ fixed->div = 6;
+
+ gate = kzalloc(sizeof(*gate), GFP_KERNEL);
+ if (!gate) {
+ kfree(fixed);
+ return ERR_PTR(-ENOMEM);
+ }
+
+ gate->reg = base + CPG_RCANCKCR;
+ gate->bit_idx = 8;
+ gate->flags = CLK_GATE_SET_TO_DISABLE;
+ gate->lock = &cpg_lock;
+
+ clk = clk_register_composite(NULL, name, &parent_name, 1, NULL, NULL,
+ &fixed->hw, &clk_fixed_factor_ops,
+ &gate->hw, &clk_gate_ops, 0);
+ if (IS_ERR(clk)) {
+ kfree(gate);
+ kfree(fixed);
+ }
+
+ return clk;
+}
+
+/* ADSP divisors */
+static const struct clk_div_table cpg_adsp_div_table[] = {
+ { 1, 3 }, { 2, 4 }, { 3, 6 }, { 4, 8 },
+ { 5, 12 }, { 6, 16 }, { 7, 18 }, { 8, 24 },
+ { 10, 36 }, { 11, 48 }, { 0, 0 },
+};
+
+static struct clk * __init cpg_adsp_clk_register(const char *name,
+ const char *parent_name,
+ void __iomem *base)
+{
+ struct clk_divider *div;
+ struct clk_gate *gate;
+ struct clk *clk;
+
+ div = kzalloc(sizeof(*div), GFP_KERNEL);
+ if (!div)
+ return ERR_PTR(-ENOMEM);
+
+ div->reg = base + CPG_ADSPCKCR;
+ div->width = 4;
+ div->table = cpg_adsp_div_table;
+ div->lock = &cpg_lock;
+
+ gate = kzalloc(sizeof(*gate), GFP_KERNEL);
+ if (!gate) {
+ kfree(div);
+ return ERR_PTR(-ENOMEM);
+ }
+
+ gate->reg = base + CPG_ADSPCKCR;
+ gate->bit_idx = 8;
+ gate->flags = CLK_GATE_SET_TO_DISABLE;
+ gate->lock = &cpg_lock;
+
+ clk = clk_register_composite(NULL, name, &parent_name, 1, NULL, NULL,
+ &div->hw, &clk_divider_ops,
+ &gate->hw, &clk_gate_ops, 0);
+ if (IS_ERR(clk)) {
+ kfree(gate);
+ kfree(div);
+ }
+
+ return clk;
+}
+
+/* SDHI divisors */
+static const struct clk_div_table cpg_sdh_div_table[] = {
+ { 0, 2 }, { 1, 3 }, { 2, 4 }, { 3, 6 },
+ { 4, 8 }, { 5, 12 }, { 6, 16 }, { 7, 18 },
+ { 8, 24 }, { 10, 36 }, { 11, 48 }, { 0, 0 },
+};
+
+static const struct clk_div_table cpg_sd01_div_table[] = {
+ { 4, 8 }, { 5, 12 }, { 6, 16 }, { 7, 18 },
+ { 8, 24 }, { 10, 36 }, { 11, 48 }, { 12, 10 },
+ { 0, 0 },
+};
+
+static const struct rcar_gen2_cpg_pll_config *cpg_pll_config __initdata;
+static u32 cpg_mode __initdata;
+
+struct clk * __init rcar_gen2_cpg_clk_register(struct device *dev,
+ const struct cpg_core_clk *core,
+ const struct cpg_mssr_info *info,
+ struct clk **clks,
+ void __iomem *base)
+{
+ const struct clk_div_table *table = NULL;
+ const struct clk *parent;
+ const char *parent_name;
+ unsigned int mult = 1;
+ unsigned int div = 1;
+ unsigned int shift;
+
+ parent = clks[core->parent];
+ if (IS_ERR(parent))
+ return ERR_CAST(parent);
+
+ parent_name = __clk_get_name(parent);
+
+ switch (core->type) {
+ /* R-Car Gen2 */
+ case CLK_TYPE_GEN2_MAIN:
+ div = cpg_pll_config->extal_div;
+ break;
+
+ case CLK_TYPE_GEN2_PLL0:
+ /*
+ * PLL0 is a configurable multiplier clock except on R-Car
+ * V2H/E2. Register the PLL0 clock as a fixed factor clock for
+ * now as there's no generic multiplier clock implementation and
+ * we currently have no need to change the multiplier value.
+ */
+ mult = cpg_pll_config->pll0_mult;
+ if (!mult) {
+ u32 pll0cr = readl(base + CPG_PLL0CR);
+
+ mult = (((pll0cr & CPG_PLL0CR_STC_MASK) >>
+ CPG_PLL0CR_STC_SHIFT) + 1) * 2;
+ }
+ break;
+
+ case CLK_TYPE_GEN2_PLL1:
+ mult = cpg_pll_config->pll1_mult / 2;
+ break;
+
+ case CLK_TYPE_GEN2_PLL3:
+ mult = cpg_pll_config->pll3_mult;
+ break;
+
+ case CLK_TYPE_GEN2_Z:
+ return cpg_z_clk_register(core->name, parent_name, base);
+
+ case CLK_TYPE_GEN2_LB:
+ div = cpg_mode & BIT(18) ? 36 : 24;
+ break;
+
+ case CLK_TYPE_GEN2_ADSP:
+ return cpg_adsp_clk_register(core->name, parent_name, base);
+
+ case CLK_TYPE_GEN2_SDH:
+ table = cpg_sdh_div_table;
+ shift = 8;
+ break;
+
+ case CLK_TYPE_GEN2_SD0:
+ table = cpg_sd01_div_table;
+ shift = 4;
+ break;
+
+ case CLK_TYPE_GEN2_SD1:
+ table = cpg_sd01_div_table;
+ shift = 0;
+ break;
+
+ case CLK_TYPE_GEN2_QSPI:
+ div = (cpg_mode & (BIT(3) | BIT(2) | BIT(1))) == BIT(2) ?
+ 8 : 10;
+ break;
+
+ case CLK_TYPE_GEN2_RCAN:
+ return cpg_rcan_clk_register(core->name, parent_name, base);
+
+ default:
+ return ERR_PTR(-EINVAL);
+ }
+
+ if (!table)
+ return clk_register_fixed_factor(NULL, core->name, parent_name,
+ 0, mult, div);
+ else
+ return clk_register_divider_table(NULL, core->name,
+ parent_name, 0,
+ base + CPG_SDCKCR, shift, 4,
+ 0, table, &cpg_lock);
+}
+
+int __init rcar_gen2_cpg_init(const struct rcar_gen2_cpg_pll_config *config)
+{
+ cpg_pll_config = config;
+
+ spin_lock_init(&cpg_lock);
+
+ return 0;
+}
Index: renesas/drivers/clk/renesas/rcar-gen2-cpg.h
===================================================================
--- /dev/null
+++ renesas/drivers/clk/renesas/rcar-gen2-cpg.h
@@ -0,0 +1,42 @@
+/*
+ * R-Car Gen2 Clock Pulse Generator
+ *
+ * Copyright (C) 2016 Cogent Embedded Inc.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published
+ * by the Free Software Foundation; version 2 of the License.
+ */
+
+#ifndef __CLK_RENESAS_RCAR_GEN2_CPG_H__
+#define __CLK_RENESAS_RCAR_GEN2_CPG_H__
+
+enum rcar_gen2_clk_types {
+ CLK_TYPE_GEN2_MAIN = CLK_TYPE_CUSTOM,
+ CLK_TYPE_GEN2_PLL0,
+ CLK_TYPE_GEN2_PLL1,
+ CLK_TYPE_GEN2_PLL3,
+ CLK_TYPE_GEN2_Z,
+ CLK_TYPE_GEN2_LB,
+ CLK_TYPE_GEN2_ADSP,
+ CLK_TYPE_GEN2_SDH,
+ CLK_TYPE_GEN2_SD0,
+ CLK_TYPE_GEN2_SD1,
+ CLK_TYPE_GEN2_QSPI,
+ CLK_TYPE_GEN2_RCAN,
+};
+
+struct rcar_gen2_cpg_pll_config {
+ unsigned int extal_div;
+ unsigned int pll1_mult;
+ unsigned int pll3_mult;
+ unsigned int pll0_mult; /* leave as zero if PLL0CR exists */
+};
+
+struct clk *rcar_gen2_cpg_clk_register(struct device *dev,
+ const struct cpg_core_clk *core,
+ const struct cpg_mssr_info *info,
+ struct clk **clks, void __iomem *base);
+int rcar_gen2_cpg_init(const struct rcar_gen2_cpg_pll_config *config);
+
+#endif
