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path: root/drivers/clk/shmobile/clk-rcar-gen2.c
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-rw-r--r--drivers/clk/shmobile/clk-rcar-gen2.c427
1 files changed, 427 insertions, 0 deletions
diff --git a/drivers/clk/shmobile/clk-rcar-gen2.c b/drivers/clk/shmobile/clk-rcar-gen2.c
new file mode 100644
index 000000000..acfb6d7db
--- /dev/null
+++ b/drivers/clk/shmobile/clk-rcar-gen2.c
@@ -0,0 +1,427 @@
+/*
+ * rcar_gen2 Core CPG Clocks
+ *
+ * Copyright (C) 2013 Ideas On Board SPRL
+ *
+ * Contact: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
+ *
+ * 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/clk-provider.h>
+#include <linux/clkdev.h>
+#include <linux/clk/shmobile.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/math64.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/spinlock.h>
+
+struct rcar_gen2_cpg {
+ struct clk_onecell_data data;
+ spinlock_t lock;
+ void __iomem *reg;
+};
+
+#define CPG_FRQCRB 0x00000004
+#define CPG_FRQCRB_KICK BIT(31)
+#define CPG_SDCKCR 0x00000074
+#define CPG_PLL0CR 0x000000d8
+#define CPG_FRQCRC 0x000000e0
+#define CPG_FRQCRC_ZFC_MASK (0x1f << 8)
+#define CPG_FRQCRC_ZFC_SHIFT 8
+#define CPG_ADSPCKCR 0x0000025c
+#define CPG_RCANCKCR 0x00000270
+
+/* -----------------------------------------------------------------------------
+ * 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 = (clk_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 (clk_readl(zclk->kick_reg) & CPG_FRQCRB_KICK)
+ return -EBUSY;
+
+ val = clk_readl(zclk->reg);
+ val &= ~CPG_FRQCRC_ZFC_MASK;
+ val |= (32 - mult) << CPG_FRQCRC_ZFC_SHIFT;
+ clk_writel(val, zclk->reg);
+
+ /*
+ * Set KICK bit in FRQCRB to update hardware setting and wait for
+ * clock change completion.
+ */
+ kick = clk_readl(zclk->kick_reg);
+ kick |= CPG_FRQCRB_KICK;
+ clk_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 dependant 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 (!(clk_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(struct rcar_gen2_cpg *cpg)
+{
+ static const char *parent_name = "pll0";
+ 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 = "z";
+ init.ops = &cpg_z_clk_ops;
+ init.flags = 0;
+ init.parent_names = &parent_name;
+ init.num_parents = 1;
+
+ zclk->reg = cpg->reg + CPG_FRQCRC;
+ zclk->kick_reg = cpg->reg + 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(struct rcar_gen2_cpg *cpg,
+ struct device_node *np)
+{
+ const char *parent_name = of_clk_get_parent_name(np, 1);
+ 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 = cpg->reg + CPG_RCANCKCR;
+ gate->bit_idx = 8;
+ gate->flags = CLK_GATE_SET_TO_DISABLE;
+ gate->lock = &cpg->lock;
+
+ clk = clk_register_composite(NULL, "rcan", &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(struct rcar_gen2_cpg *cpg)
+{
+ const char *parent_name = "pll1";
+ 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 = cpg->reg + 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 = cpg->reg + CPG_ADSPCKCR;
+ gate->bit_idx = 8;
+ gate->flags = CLK_GATE_SET_TO_DISABLE;
+ gate->lock = &cpg->lock;
+
+ clk = clk_register_composite(NULL, "adsp", &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;
+}
+
+/* -----------------------------------------------------------------------------
+ * CPG Clock Data
+ */
+
+/*
+ * MD EXTAL PLL0 PLL1 PLL3
+ * 14 13 19 (MHz) *1 *1
+ *---------------------------------------------------
+ * 0 0 0 15 x 1 x172/2 x208/2 x106
+ * 0 0 1 15 x 1 x172/2 x208/2 x88
+ * 0 1 0 20 x 1 x130/2 x156/2 x80
+ * 0 1 1 20 x 1 x130/2 x156/2 x66
+ * 1 0 0 26 / 2 x200/2 x240/2 x122
+ * 1 0 1 26 / 2 x200/2 x240/2 x102
+ * 1 1 0 30 / 2 x172/2 x208/2 x106
+ * 1 1 1 30 / 2 x172/2 x208/2 x88
+ *
+ * *1 : Table 7.6 indicates VCO ouput (PLLx = VCO/2)
+ */
+#define CPG_PLL_CONFIG_INDEX(md) ((((md) & BIT(14)) >> 12) | \
+ (((md) & BIT(13)) >> 12) | \
+ (((md) & BIT(19)) >> 19))
+struct cpg_pll_config {
+ unsigned int extal_div;
+ unsigned int pll1_mult;
+ unsigned int pll3_mult;
+};
+
+static const struct cpg_pll_config cpg_pll_configs[8] __initconst = {
+ { 1, 208, 106 }, { 1, 208, 88 }, { 1, 156, 80 }, { 1, 156, 66 },
+ { 2, 240, 122 }, { 2, 240, 102 }, { 2, 208, 106 }, { 2, 208, 88 },
+};
+
+/* 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 },
+};
+
+/* -----------------------------------------------------------------------------
+ * Initialization
+ */
+
+static u32 cpg_mode __initdata;
+
+static struct clk * __init
+rcar_gen2_cpg_register_clock(struct device_node *np, struct rcar_gen2_cpg *cpg,
+ const struct cpg_pll_config *config,
+ const char *name)
+{
+ const struct clk_div_table *table = NULL;
+ const char *parent_name;
+ unsigned int shift;
+ unsigned int mult = 1;
+ unsigned int div = 1;
+
+ if (!strcmp(name, "main")) {
+ parent_name = of_clk_get_parent_name(np, 0);
+ div = config->extal_div;
+ } else if (!strcmp(name, "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.
+ */
+ u32 value = clk_readl(cpg->reg + CPG_PLL0CR);
+ parent_name = "main";
+ mult = ((value >> 24) & ((1 << 7) - 1)) + 1;
+ } else if (!strcmp(name, "pll1")) {
+ parent_name = "main";
+ mult = config->pll1_mult / 2;
+ } else if (!strcmp(name, "pll3")) {
+ parent_name = "main";
+ mult = config->pll3_mult;
+ } else if (!strcmp(name, "lb")) {
+ parent_name = "pll1";
+ div = cpg_mode & BIT(18) ? 36 : 24;
+ } else if (!strcmp(name, "qspi")) {
+ parent_name = "pll1_div2";
+ div = (cpg_mode & (BIT(3) | BIT(2) | BIT(1))) == BIT(2)
+ ? 8 : 10;
+ } else if (!strcmp(name, "sdh")) {
+ parent_name = "pll1";
+ table = cpg_sdh_div_table;
+ shift = 8;
+ } else if (!strcmp(name, "sd0")) {
+ parent_name = "pll1";
+ table = cpg_sd01_div_table;
+ shift = 4;
+ } else if (!strcmp(name, "sd1")) {
+ parent_name = "pll1";
+ table = cpg_sd01_div_table;
+ shift = 0;
+ } else if (!strcmp(name, "z")) {
+ return cpg_z_clk_register(cpg);
+ } else if (!strcmp(name, "rcan")) {
+ return cpg_rcan_clk_register(cpg, np);
+ } else if (!strcmp(name, "adsp")) {
+ return cpg_adsp_clk_register(cpg);
+ } else {
+ return ERR_PTR(-EINVAL);
+ }
+
+ if (!table)
+ return clk_register_fixed_factor(NULL, name, parent_name, 0,
+ mult, div);
+ else
+ return clk_register_divider_table(NULL, name, parent_name, 0,
+ cpg->reg + CPG_SDCKCR, shift,
+ 4, 0, table, &cpg->lock);
+}
+
+static void __init rcar_gen2_cpg_clocks_init(struct device_node *np)
+{
+ const struct cpg_pll_config *config;
+ struct rcar_gen2_cpg *cpg;
+ struct clk **clks;
+ unsigned int i;
+ int num_clks;
+
+ num_clks = of_property_count_strings(np, "clock-output-names");
+ if (num_clks < 0) {
+ pr_err("%s: failed to count clocks\n", __func__);
+ return;
+ }
+
+ cpg = kzalloc(sizeof(*cpg), GFP_KERNEL);
+ clks = kzalloc(num_clks * sizeof(*clks), GFP_KERNEL);
+ if (cpg == NULL || clks == NULL) {
+ /* We're leaking memory on purpose, there's no point in cleaning
+ * up as the system won't boot anyway.
+ */
+ pr_err("%s: failed to allocate cpg\n", __func__);
+ return;
+ }
+
+ spin_lock_init(&cpg->lock);
+
+ cpg->data.clks = clks;
+ cpg->data.clk_num = num_clks;
+
+ cpg->reg = of_iomap(np, 0);
+ if (WARN_ON(cpg->reg == NULL))
+ return;
+
+ config = &cpg_pll_configs[CPG_PLL_CONFIG_INDEX(cpg_mode)];
+
+ for (i = 0; i < num_clks; ++i) {
+ const char *name;
+ struct clk *clk;
+
+ of_property_read_string_index(np, "clock-output-names", i,
+ &name);
+
+ clk = rcar_gen2_cpg_register_clock(np, cpg, config, name);
+ if (IS_ERR(clk))
+ pr_err("%s: failed to register %s %s clock (%ld)\n",
+ __func__, np->name, name, PTR_ERR(clk));
+ else
+ cpg->data.clks[i] = clk;
+ }
+
+ of_clk_add_provider(np, of_clk_src_onecell_get, &cpg->data);
+}
+CLK_OF_DECLARE(rcar_gen2_cpg_clks, "renesas,rcar-gen2-cpg-clocks",
+ rcar_gen2_cpg_clocks_init);
+
+void __init rcar_gen2_clocks_init(u32 mode)
+{
+ cpg_mode = mode;
+
+ of_clk_init(NULL);
+}
generated by cgit v1.2.3-54-g00ecf (git 2.45.2) at 2024-11-16 21:11:18 +0000