summaryrefslogtreecommitdiffstats
path: root/drivers/clk/renesas/rcar-gen3-cpg.c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/clk/renesas/rcar-gen3-cpg.c')
-rw-r--r--drivers/clk/renesas/rcar-gen3-cpg.c557
1 files changed, 557 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 0000000000..d0129a6509
--- /dev/null
+++ b/drivers/clk/renesas/rcar-gen3-cpg.c
@@ -0,0 +1,557 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * R-Car Gen3 Clock Pulse Generator
+ *
+ * Copyright (C) 2015-2018 Glider bvba
+ * Copyright (C) 2019 Renesas Electronics Corp.
+ *
+ * Based on clk-rcar-gen3.c
+ *
+ * Copyright (C) 2015 Renesas Electronics Corp.
+ */
+
+#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-cpg-lib.h"
+#include "rcar-gen3-cpg.h"
+
+#define CPG_PLLECR 0x00d0 /* PLL Enable Control Register */
+
+#define CPG_PLLECR_PLLST(n) BIT(8 + (n)) /* PLLn Circuit Status */
+
+#define CPG_PLL0CR 0x00d8 /* PLLn Control Registers */
+#define CPG_PLL2CR 0x002c
+#define CPG_PLL4CR 0x01f4
+
+#define CPG_PLLnCR_STC_MASK GENMASK(30, 24) /* PLL Circuit Mult. Ratio */
+
+#define CPG_RCKCR_CKSEL BIT(15) /* RCLK Clock Source Select */
+
+/* PLL Clocks */
+struct cpg_pll_clk {
+ struct clk_hw hw;
+ void __iomem *pllcr_reg;
+ void __iomem *pllecr_reg;
+ unsigned int fixed_mult;
+ u32 pllecr_pllst_mask;
+};
+
+#define to_pll_clk(_hw) container_of(_hw, struct cpg_pll_clk, hw)
+
+static unsigned long cpg_pll_clk_recalc_rate(struct clk_hw *hw,
+ unsigned long parent_rate)
+{
+ struct cpg_pll_clk *pll_clk = to_pll_clk(hw);
+ unsigned int mult;
+ u32 val;
+
+ val = readl(pll_clk->pllcr_reg) & CPG_PLLnCR_STC_MASK;
+ mult = (val >> __ffs(CPG_PLLnCR_STC_MASK)) + 1;
+
+ return parent_rate * mult * pll_clk->fixed_mult;
+}
+
+static int cpg_pll_clk_determine_rate(struct clk_hw *hw,
+ struct clk_rate_request *req)
+{
+ struct cpg_pll_clk *pll_clk = to_pll_clk(hw);
+ unsigned int min_mult, max_mult, mult;
+ unsigned long prate;
+
+ prate = req->best_parent_rate * pll_clk->fixed_mult;
+ min_mult = max(div64_ul(req->min_rate, prate), 1ULL);
+ max_mult = min(div64_ul(req->max_rate, prate), 128ULL);
+ if (max_mult < min_mult)
+ return -EINVAL;
+
+ mult = DIV_ROUND_CLOSEST_ULL(req->rate, prate);
+ mult = clamp(mult, min_mult, max_mult);
+
+ req->rate = prate * mult;
+ return 0;
+}
+
+static int cpg_pll_clk_set_rate(struct clk_hw *hw, unsigned long rate,
+ unsigned long parent_rate)
+{
+ struct cpg_pll_clk *pll_clk = to_pll_clk(hw);
+ unsigned int mult, i;
+ u32 val;
+
+ mult = DIV_ROUND_CLOSEST_ULL(rate, parent_rate * pll_clk->fixed_mult);
+ mult = clamp(mult, 1U, 128U);
+
+ val = readl(pll_clk->pllcr_reg);
+ val &= ~CPG_PLLnCR_STC_MASK;
+ val |= (mult - 1) << __ffs(CPG_PLLnCR_STC_MASK);
+ writel(val, pll_clk->pllcr_reg);
+
+ for (i = 1000; i; i--) {
+ if (readl(pll_clk->pllecr_reg) & pll_clk->pllecr_pllst_mask)
+ return 0;
+
+ cpu_relax();
+ }
+
+ return -ETIMEDOUT;
+}
+
+static const struct clk_ops cpg_pll_clk_ops = {
+ .recalc_rate = cpg_pll_clk_recalc_rate,
+ .determine_rate = cpg_pll_clk_determine_rate,
+ .set_rate = cpg_pll_clk_set_rate,
+};
+
+static struct clk * __init cpg_pll_clk_register(const char *name,
+ const char *parent_name,
+ void __iomem *base,
+ unsigned int mult,
+ unsigned int offset,
+ unsigned int index)
+
+{
+ struct cpg_pll_clk *pll_clk;
+ struct clk_init_data init = {};
+ struct clk *clk;
+
+ pll_clk = kzalloc(sizeof(*pll_clk), GFP_KERNEL);
+ if (!pll_clk)
+ return ERR_PTR(-ENOMEM);
+
+ init.name = name;
+ init.ops = &cpg_pll_clk_ops;
+ init.parent_names = &parent_name;
+ init.num_parents = 1;
+
+ pll_clk->hw.init = &init;
+ pll_clk->pllcr_reg = base + offset;
+ pll_clk->pllecr_reg = base + CPG_PLLECR;
+ pll_clk->fixed_mult = mult; /* PLL refclk x (setting + 1) x mult */
+ pll_clk->pllecr_pllst_mask = CPG_PLLECR_PLLST(index);
+
+ clk = clk_register(NULL, &pll_clk->hw);
+ if (IS_ERR(clk))
+ kfree(pll_clk);
+
+ return clk;
+}
+
+/*
+ * 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 ) / fixed_div
+ * parent - fixed parent. No clk_set_parent support
+ */
+#define CPG_FRQCRB 0x00000004
+#define CPG_FRQCRB_KICK BIT(31)
+#define CPG_FRQCRC 0x000000e0
+
+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,
+ unsigned int fcr,
+ unsigned int flags)
+{
+ 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 = flags;
+ init.parent_names = &parent_name;
+ init.num_parents = 1;
+
+ zclk->reg = reg + fcr;
+ 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;
+}
+
+static struct clk * __init cpg_z_clk_register(const char *name,
+ const char *parent_name,
+ void __iomem *reg,
+ unsigned int div,
+ unsigned int offset)
+{
+ return __cpg_z_clk_register(name, parent_name, reg, div, offset,
+ CPG_FRQCRC, CLK_SET_RATE_PARENT);
+}
+
+static struct clk * __init cpg_zg_clk_register(const char *name,
+ const char *parent_name,
+ void __iomem *reg,
+ unsigned int div,
+ unsigned int offset)
+{
+ return __cpg_z_clk_register(name, parent_name, reg, div, offset,
+ CPG_FRQCRB, 0);
+
+}
+
+static const struct clk_div_table cpg_rpcsrc_div_table[] = {
+ { 2, 5 }, { 3, 6 }, { 0, 0 },
+};
+
+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 RCKCR_CKSEL BIT(1) /* Manual RCLK parent selection */
+
+
+static const struct soc_device_attribute cpg_quirks_match[] __initconst = {
+ {
+ .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]; /* some types use 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 implemented as a custom clock, to change the
+ * multiplier when cpufreq changes between normal and boost
+ * modes.
+ */
+ return cpg_pll_clk_register(core->name, __clk_get_name(parent),
+ base, 2, CPG_PLL0CR, 0);
+
+ 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 implemented as a custom clock, to change the
+ * multiplier when cpufreq changes between normal and boost
+ * modes.
+ */
+ return cpg_pll_clk_register(core->name, __clk_get_name(parent),
+ base, 2, CPG_PLL2CR, 2);
+
+ 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;
+ break;
+
+ case CLK_TYPE_GEN3_SDH:
+ return cpg_sdh_clk_register(core->name, base + core->offset,
+ __clk_get_name(parent), notifiers);
+
+ case CLK_TYPE_GEN3_SD:
+ return cpg_sd_clk_register(core->name, base + core->offset,
+ __clk_get_name(parent));
+
+ 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 |= CPG_RCKCR_CKSEL;
+ }
+
+ 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_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_GEN3_Z:
+ return cpg_z_clk_register(core->name, __clk_get_name(parent),
+ base, core->div, core->offset);
+
+ case CLK_TYPE_GEN3_ZG:
+ return cpg_zg_clk_register(core->name, __clk_get_name(parent),
+ base, core->div, core->offset);
+
+ case CLK_TYPE_GEN3_OSC:
+ /*
+ * Clock combining OSC EXTAL predivider and a fixed divider
+ */
+ div = cpg_pll_config->osc_prediv * core->div;
+ break;
+
+ case CLK_TYPE_GEN3_RCKSEL:
+ /*
+ * Clock selectable between two parents and two fixed dividers
+ * using RCKCR.CKSEL
+ */
+ if (readl(base + CPG_RCKCR) & CPG_RCKCR_CKSEL) {
+ div = core->div & 0xffff;
+ } else {
+ parent = clks[core->parent >> 16];
+ if (IS_ERR(parent))
+ return ERR_CAST(parent);
+ div = core->div >> 16;
+ }
+ break;
+
+ case CLK_TYPE_GEN3_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_GEN3_E3_RPCSRC:
+ /*
+ * Register RPCSRC as fixed factor clock based on the
+ * MD[4:1] pins and CPG_RPCCKCR[4:3] register value for
+ * which has been set prior to booting the kernel.
+ */
+ value = (readl(base + CPG_RPCCKCR) & GENMASK(4, 3)) >> 3;
+
+ switch (value) {
+ case 0:
+ div = 5;
+ break;
+ case 1:
+ div = 3;
+ break;
+ case 2:
+ parent = clks[core->parent >> 16];
+ if (IS_ERR(parent))
+ return ERR_CAST(parent);
+ div = core->div;
+ break;
+ case 3:
+ default:
+ div = 2;
+ break;
+ }
+ break;
+
+ case CLK_TYPE_GEN3_RPC:
+ return cpg_rpc_clk_register(core->name, base + CPG_RPCCKCR,
+ __clk_get_name(parent), notifiers);
+
+ case CLK_TYPE_GEN3_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_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);
+
+ spin_lock_init(&cpg_lock);
+
+ return 0;
+}
generated by cgit v1.2.3 (git 2.39.1) at 2024-08-14 21:17:01 +0000