cregit-Linux how code gets into the kernel

Release 4.11 drivers/clk/renesas/rcar-gen2-cpg.c

/*
 * 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); }

Contributors

PersonTokensPropCommitsCommitProp
Sergei Shtylyov68100.00%1100.00%
Total68100.00%1100.00%


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; }

Contributors

PersonTokensPropCommitsCommitProp
Sergei Shtylyov73100.00%1100.00%
Total73100.00%1100.00%


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; }

Contributors

PersonTokensPropCommitsCommitProp
Sergei Shtylyov176100.00%1100.00%
Total176100.00%1100.00%

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; }

Contributors

PersonTokensPropCommitsCommitProp
Sergei Shtylyov147100.00%1100.00%
Total147100.00%1100.00%


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; }

Contributors

PersonTokensPropCommitsCommitProp
Sergei Shtylyov193100.00%1100.00%
Total193100.00%1100.00%

/* 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; }

Contributors

PersonTokensPropCommitsCommitProp
Sergei Shtylyov208100.00%1100.00%
Total208100.00%1100.00%

/* 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 unsigned int cpg_pll0_div __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; div = cpg_pll0_div; 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); }

Contributors

PersonTokensPropCommitsCommitProp
Sergei Shtylyov386100.00%1100.00%
Total386100.00%1100.00%


int __init rcar_gen2_cpg_init(const struct rcar_gen2_cpg_pll_config *config, unsigned int pll0_div, u32 mode) { cpg_pll_config = config; cpg_pll0_div = pll0_div; cpg_mode = mode; spin_lock_init(&cpg_lock); return 0; }

Contributors

PersonTokensPropCommitsCommitProp
Sergei Shtylyov40100.00%1100.00%
Total40100.00%1100.00%


Overall Contributors

PersonTokensPropCommitsCommitProp
Sergei Shtylyov1660100.00%1100.00%
Total1660100.00%1100.00%
Information contained on this website is for historical information purposes only and does not indicate or represent copyright ownership.
Created with cregit.