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-rw-r--r--drivers/clk/renesas/rcar-gen3-cpg.c579
1 files changed, 579 insertions, 0 deletions
diff --git a/drivers/clk/renesas/rcar-gen3-cpg.c b/drivers/clk/renesas/rcar-gen3-cpg.c
new file mode 100644
index 000000000..9ace7d39c
--- /dev/null
+++ b/drivers/clk/renesas/rcar-gen3-cpg.c
@@ -0,0 +1,579 @@
+/*
+ * R-Car Gen3 Clock Pulse Generator
+ *
+ * Copyright (C) 2015-2016 Glider bvba
+ *
+ * Based on clk-rcar-gen3.c
+ *
+ * Copyright (C) 2015 Renesas Electronics Corp.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 of the License.
+ */
+
+#include <linux/bug.h>
+#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/pm.h>
+#include <linux/slab.h>
+#include <linux/sys_soc.h>
+
+#include "renesas-cpg-mssr.h"
+#include "rcar-gen3-cpg.h"
+
+#define CPG_PLL0CR 0x00d8
+#define CPG_PLL2CR 0x002c
+#define CPG_PLL4CR 0x01f4
+
+struct cpg_simple_notifier {
+ struct notifier_block nb;
+ void __iomem *reg;
+ u32 saved;
+};
+
+static int cpg_simple_notifier_call(struct notifier_block *nb,
+ unsigned long action, void *data)
+{
+ struct cpg_simple_notifier *csn =
+ container_of(nb, struct cpg_simple_notifier, nb);
+
+ switch (action) {
+ case PM_EVENT_SUSPEND:
+ csn->saved = readl(csn->reg);
+ return NOTIFY_OK;
+
+ case PM_EVENT_RESUME:
+ writel(csn->saved, csn->reg);
+ return NOTIFY_OK;
+ }
+ return NOTIFY_DONE;
+}
+
+static void cpg_simple_notifier_register(struct raw_notifier_head *notifiers,
+ struct cpg_simple_notifier *csn)
+{
+ csn->nb.notifier_call = cpg_simple_notifier_call;
+ raw_notifier_chain_register(notifiers, &csn->nb);
+}
+
+/*
+ * Z Clock & Z2 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 ) / 2
+ * parent - fixed parent. No clk_set_parent support
+ */
+#define CPG_FRQCRB 0x00000004
+#define CPG_FRQCRB_KICK BIT(31)
+#define CPG_FRQCRC 0x000000e0
+#define CPG_FRQCRC_ZFC_MASK GENMASK(12, 8)
+#define CPG_FRQCRC_Z2FC_MASK GENMASK(4, 0)
+
+struct cpg_z_clk {
+ struct clk_hw hw;
+ void __iomem *reg;
+ void __iomem *kick_reg;
+ unsigned long 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));
+
+ /* Factor of 2 is for fixed divider */
+ return DIV_ROUND_CLOSEST_ULL((u64)parent_rate * mult, 32 * 2);
+}
+
+static long cpg_z_clk_round_rate(struct clk_hw *hw, unsigned long rate,
+ unsigned long *parent_rate)
+{
+ /* Factor of 2 is for fixed divider */
+ unsigned long prate = *parent_rate / 2;
+ unsigned int mult;
+
+ mult = div_u64(rate * 32ULL, prate);
+ mult = clamp(mult, 1U, 32U);
+
+ return (u64)prate * mult / 32;
+}
+
+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;
+ u32 val, kick;
+
+ /* Factor of 2 is for fixed divider */
+ mult = DIV_ROUND_CLOSEST_ULL(rate * 32ULL * 2, parent_rate);
+ mult = clamp(mult, 1U, 32U);
+
+ if (readl(zclk->kick_reg) & CPG_FRQCRB_KICK)
+ return -EBUSY;
+
+ val = readl(zclk->reg) & ~zclk->mask;
+ val |= ((32 - mult) << __ffs(zclk->mask)) & zclk->mask;
+ 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 of 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 *reg,
+ unsigned long mask)
+{
+ 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 = reg + CPG_FRQCRC;
+ zclk->kick_reg = reg + CPG_FRQCRB;
+ zclk->hw.init = &init;
+ zclk->mask = mask;
+
+ clk = clk_register(NULL, &zclk->hw);
+ if (IS_ERR(clk))
+ kfree(zclk);
+
+ return clk;
+}
+
+/*
+ * SDn Clock
+ */
+#define CPG_SD_STP_HCK BIT(9)
+#define CPG_SD_STP_CK BIT(8)
+
+#define CPG_SD_STP_MASK (CPG_SD_STP_HCK | CPG_SD_STP_CK)
+#define CPG_SD_FC_MASK (0x7 << 2 | 0x3 << 0)
+
+#define CPG_SD_DIV_TABLE_DATA(stp_hck, stp_ck, sd_srcfc, sd_fc, sd_div) \
+{ \
+ .val = ((stp_hck) ? CPG_SD_STP_HCK : 0) | \
+ ((stp_ck) ? CPG_SD_STP_CK : 0) | \
+ ((sd_srcfc) << 2) | \
+ ((sd_fc) << 0), \
+ .div = (sd_div), \
+}
+
+struct sd_div_table {
+ u32 val;
+ unsigned int div;
+};
+
+struct sd_clock {
+ struct clk_hw hw;
+ const struct sd_div_table *div_table;
+ struct cpg_simple_notifier csn;
+ unsigned int div_num;
+ unsigned int div_min;
+ unsigned int div_max;
+ unsigned int cur_div_idx;
+};
+
+/* SDn divider
+ * sd_srcfc sd_fc div
+ * stp_hck stp_ck (div) (div) = sd_srcfc x sd_fc
+ *-------------------------------------------------------------------
+ * 0 0 0 (1) 1 (4) 4
+ * 0 0 1 (2) 1 (4) 8
+ * 1 0 2 (4) 1 (4) 16
+ * 1 0 3 (8) 1 (4) 32
+ * 1 0 4 (16) 1 (4) 64
+ * 0 0 0 (1) 0 (2) 2
+ * 0 0 1 (2) 0 (2) 4
+ * 1 0 2 (4) 0 (2) 8
+ * 1 0 3 (8) 0 (2) 16
+ * 1 0 4 (16) 0 (2) 32
+ */
+static const struct sd_div_table cpg_sd_div_table[] = {
+/* CPG_SD_DIV_TABLE_DATA(stp_hck, stp_ck, sd_srcfc, sd_fc, sd_div) */
+ CPG_SD_DIV_TABLE_DATA(0, 0, 0, 1, 4),
+ CPG_SD_DIV_TABLE_DATA(0, 0, 1, 1, 8),
+ CPG_SD_DIV_TABLE_DATA(1, 0, 2, 1, 16),
+ CPG_SD_DIV_TABLE_DATA(1, 0, 3, 1, 32),
+ CPG_SD_DIV_TABLE_DATA(1, 0, 4, 1, 64),
+ CPG_SD_DIV_TABLE_DATA(0, 0, 0, 0, 2),
+ CPG_SD_DIV_TABLE_DATA(0, 0, 1, 0, 4),
+ CPG_SD_DIV_TABLE_DATA(1, 0, 2, 0, 8),
+ CPG_SD_DIV_TABLE_DATA(1, 0, 3, 0, 16),
+ CPG_SD_DIV_TABLE_DATA(1, 0, 4, 0, 32),
+};
+
+#define to_sd_clock(_hw) container_of(_hw, struct sd_clock, hw)
+
+static int cpg_sd_clock_enable(struct clk_hw *hw)
+{
+ struct sd_clock *clock = to_sd_clock(hw);
+ u32 val = readl(clock->csn.reg);
+
+ val &= ~(CPG_SD_STP_MASK);
+ val |= clock->div_table[clock->cur_div_idx].val & CPG_SD_STP_MASK;
+
+ writel(val, clock->csn.reg);
+
+ return 0;
+}
+
+static void cpg_sd_clock_disable(struct clk_hw *hw)
+{
+ struct sd_clock *clock = to_sd_clock(hw);
+
+ writel(readl(clock->csn.reg) | CPG_SD_STP_MASK, clock->csn.reg);
+}
+
+static int cpg_sd_clock_is_enabled(struct clk_hw *hw)
+{
+ struct sd_clock *clock = to_sd_clock(hw);
+
+ return !(readl(clock->csn.reg) & CPG_SD_STP_MASK);
+}
+
+static unsigned long cpg_sd_clock_recalc_rate(struct clk_hw *hw,
+ unsigned long parent_rate)
+{
+ struct sd_clock *clock = to_sd_clock(hw);
+
+ return DIV_ROUND_CLOSEST(parent_rate,
+ clock->div_table[clock->cur_div_idx].div);
+}
+
+static unsigned int cpg_sd_clock_calc_div(struct sd_clock *clock,
+ unsigned long rate,
+ unsigned long parent_rate)
+{
+ unsigned int div;
+
+ if (!rate)
+ rate = 1;
+
+ div = DIV_ROUND_CLOSEST(parent_rate, rate);
+
+ return clamp_t(unsigned int, div, clock->div_min, clock->div_max);
+}
+
+static long cpg_sd_clock_round_rate(struct clk_hw *hw, unsigned long rate,
+ unsigned long *parent_rate)
+{
+ struct sd_clock *clock = to_sd_clock(hw);
+ unsigned int div = cpg_sd_clock_calc_div(clock, rate, *parent_rate);
+
+ return DIV_ROUND_CLOSEST(*parent_rate, div);
+}
+
+static int cpg_sd_clock_set_rate(struct clk_hw *hw, unsigned long rate,
+ unsigned long parent_rate)
+{
+ struct sd_clock *clock = to_sd_clock(hw);
+ unsigned int div = cpg_sd_clock_calc_div(clock, rate, parent_rate);
+ u32 val;
+ unsigned int i;
+
+ for (i = 0; i < clock->div_num; i++)
+ if (div == clock->div_table[i].div)
+ break;
+
+ if (i >= clock->div_num)
+ return -EINVAL;
+
+ clock->cur_div_idx = i;
+
+ val = readl(clock->csn.reg);
+ val &= ~(CPG_SD_STP_MASK | CPG_SD_FC_MASK);
+ val |= clock->div_table[i].val & (CPG_SD_STP_MASK | CPG_SD_FC_MASK);
+ writel(val, clock->csn.reg);
+
+ return 0;
+}
+
+static const struct clk_ops cpg_sd_clock_ops = {
+ .enable = cpg_sd_clock_enable,
+ .disable = cpg_sd_clock_disable,
+ .is_enabled = cpg_sd_clock_is_enabled,
+ .recalc_rate = cpg_sd_clock_recalc_rate,
+ .round_rate = cpg_sd_clock_round_rate,
+ .set_rate = cpg_sd_clock_set_rate,
+};
+
+static struct clk * __init cpg_sd_clk_register(const struct cpg_core_clk *core,
+ void __iomem *base, const char *parent_name,
+ struct raw_notifier_head *notifiers)
+{
+ struct clk_init_data init;
+ struct sd_clock *clock;
+ struct clk *clk;
+ unsigned int i;
+ u32 val;
+
+ clock = kzalloc(sizeof(*clock), GFP_KERNEL);
+ if (!clock)
+ return ERR_PTR(-ENOMEM);
+
+ init.name = core->name;
+ init.ops = &cpg_sd_clock_ops;
+ init.flags = CLK_IS_BASIC | CLK_SET_RATE_PARENT;
+ init.parent_names = &parent_name;
+ init.num_parents = 1;
+
+ clock->csn.reg = base + core->offset;
+ clock->hw.init = &init;
+ clock->div_table = cpg_sd_div_table;
+ clock->div_num = ARRAY_SIZE(cpg_sd_div_table);
+
+ val = readl(clock->csn.reg) & ~CPG_SD_FC_MASK;
+ val |= CPG_SD_STP_MASK | (clock->div_table[0].val & CPG_SD_FC_MASK);
+ writel(val, clock->csn.reg);
+
+ clock->div_max = clock->div_table[0].div;
+ clock->div_min = clock->div_max;
+ for (i = 1; i < clock->div_num; i++) {
+ clock->div_max = max(clock->div_max, clock->div_table[i].div);
+ clock->div_min = min(clock->div_min, clock->div_table[i].div);
+ }
+
+ clk = clk_register(NULL, &clock->hw);
+ if (IS_ERR(clk))
+ goto free_clock;
+
+ cpg_simple_notifier_register(notifiers, &clock->csn);
+ return clk;
+
+free_clock:
+ kfree(clock);
+ return clk;
+}
+
+
+static const struct rcar_gen3_cpg_pll_config *cpg_pll_config __initdata;
+static unsigned int cpg_clk_extalr __initdata;
+static u32 cpg_mode __initdata;
+static u32 cpg_quirks __initdata;
+
+#define PLL_ERRATA BIT(0) /* Missing PLL0/2/4 post-divider */
+#define RCKCR_CKSEL BIT(1) /* Manual RCLK parent selection */
+
+static const struct soc_device_attribute cpg_quirks_match[] __initconst = {
+ {
+ .soc_id = "r8a7795", .revision = "ES1.0",
+ .data = (void *)(PLL_ERRATA | RCKCR_CKSEL),
+ },
+ {
+ .soc_id = "r8a7795", .revision = "ES1.*",
+ .data = (void *)RCKCR_CKSEL,
+ },
+ {
+ .soc_id = "r8a7796", .revision = "ES1.0",
+ .data = (void *)RCKCR_CKSEL,
+ },
+ { /* sentinel */ }
+};
+
+struct clk * __init rcar_gen3_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]; /* CLK_TYPE_PE uses high bits */
+ if (IS_ERR(parent))
+ return ERR_CAST(parent);
+
+ switch (core->type) {
+ case CLK_TYPE_GEN3_MAIN:
+ div = cpg_pll_config->extal_div;
+ break;
+
+ case CLK_TYPE_GEN3_PLL0:
+ /*
+ * PLL0 is a configurable multiplier clock. Register it 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.
+ */
+ value = readl(base + CPG_PLL0CR);
+ mult = (((value >> 24) & 0x7f) + 1) * 2;
+ if (cpg_quirks & PLL_ERRATA)
+ mult *= 2;
+ break;
+
+ case CLK_TYPE_GEN3_PLL1:
+ mult = cpg_pll_config->pll1_mult;
+ div = cpg_pll_config->pll1_div;
+ break;
+
+ case CLK_TYPE_GEN3_PLL2:
+ /*
+ * PLL2 is a configurable multiplier clock. Register it 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.
+ */
+ value = readl(base + CPG_PLL2CR);
+ mult = (((value >> 24) & 0x7f) + 1) * 2;
+ if (cpg_quirks & PLL_ERRATA)
+ mult *= 2;
+ break;
+
+ case CLK_TYPE_GEN3_PLL3:
+ mult = cpg_pll_config->pll3_mult;
+ div = cpg_pll_config->pll3_div;
+ break;
+
+ case CLK_TYPE_GEN3_PLL4:
+ /*
+ * PLL4 is a configurable multiplier clock. Register it 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.
+ */
+ value = readl(base + CPG_PLL4CR);
+ mult = (((value >> 24) & 0x7f) + 1) * 2;
+ if (cpg_quirks & PLL_ERRATA)
+ mult *= 2;
+ break;
+
+ case CLK_TYPE_GEN3_SD:
+ return cpg_sd_clk_register(core, base, __clk_get_name(parent),
+ notifiers);
+
+ case CLK_TYPE_GEN3_R:
+ if (cpg_quirks & RCKCR_CKSEL) {
+ struct cpg_simple_notifier *csn;
+
+ csn = kzalloc(sizeof(*csn), GFP_KERNEL);
+ if (!csn)
+ return ERR_PTR(-ENOMEM);
+
+ csn->reg = base + CPG_RCKCR;
+
+ /*
+ * RINT is default.
+ * Only if EXTALR is populated, we switch to it.
+ */
+ value = readl(csn->reg) & 0x3f;
+
+ if (clk_get_rate(clks[cpg_clk_extalr])) {
+ parent = clks[cpg_clk_extalr];
+ value |= BIT(15);
+ }
+
+ writel(value, csn->reg);
+ cpg_simple_notifier_register(notifiers, csn);
+ break;
+ }
+
+ /* Select parent clock of RCLK by MD28 */
+ if (cpg_mode & BIT(28))
+ parent = clks[cpg_clk_extalr];
+ break;
+
+ case CLK_TYPE_GEN3_PE:
+ /*
+ * Peripheral clock with a fixed divider, selectable between
+ * clean and spread spectrum parents using MD12
+ */
+ if (cpg_mode & BIT(12)) {
+ /* Clean */
+ div = core->div & 0xffff;
+ } else {
+ /* SCCG */
+ parent = clks[core->parent >> 16];
+ if (IS_ERR(parent))
+ return ERR_CAST(parent);
+ div = core->div >> 16;
+ }
+ mult = 1;
+ break;
+
+ case CLK_TYPE_GEN3_Z:
+ return cpg_z_clk_register(core->name, __clk_get_name(parent),
+ base, CPG_FRQCRC_ZFC_MASK);
+
+ case CLK_TYPE_GEN3_Z2:
+ return cpg_z_clk_register(core->name, __clk_get_name(parent),
+ base, CPG_FRQCRC_Z2FC_MASK);
+
+ default:
+ return ERR_PTR(-EINVAL);
+ }
+
+ return clk_register_fixed_factor(NULL, core->name,
+ __clk_get_name(parent), 0, mult, div);
+}
+
+int __init rcar_gen3_cpg_init(const struct rcar_gen3_cpg_pll_config *config,
+ unsigned int clk_extalr, u32 mode)
+{
+ const struct soc_device_attribute *attr;
+
+ cpg_pll_config = config;
+ cpg_clk_extalr = clk_extalr;
+ cpg_mode = mode;
+ attr = soc_device_match(cpg_quirks_match);
+ if (attr)
+ cpg_quirks = (uintptr_t)attr->data;
+ pr_debug("%s: mode = 0x%x quirks = 0x%x\n", __func__, mode, cpg_quirks);
+ return 0;
+}
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-27 08:55:50 +0000