| // SPDX-License-Identifier: GPL-2.0 |
| /* |
| * R-Car Gen4 Clock Pulse Generator |
| * |
| * Copyright (C) 2021 Renesas Electronics Corp. |
| * |
| * Based on rcar-gen3-cpg.c |
| * |
| * Copyright (C) 2015-2018 Glider bvba |
| * Copyright (C) 2019 Renesas Electronics Corp. |
| */ |
| |
| #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/iopoll.h> |
| #include <linux/slab.h> |
| |
| #include "renesas-cpg-mssr.h" |
| #include "rcar-gen4-cpg.h" |
| #include "rcar-cpg-lib.h" |
| |
| static const struct rcar_gen4_cpg_pll_config *cpg_pll_config __initdata; |
| static unsigned int cpg_clk_extalr __initdata; |
| static u32 cpg_mode __initdata; |
| |
| #define CPG_PLLECR 0x0820 /* PLL Enable Control Register */ |
| |
| #define CPG_PLLECR_PLLST(n) BIT(8 + ((n) < 3 ? (n) - 1 : \ |
| (n) > 3 ? (n) + 1 : n)) /* PLLn Circuit Status */ |
| |
| #define CPG_PLL1CR0 0x830 /* PLLn Control Registers */ |
| #define CPG_PLL1CR1 0x8b0 |
| #define CPG_PLL2CR0 0x834 |
| #define CPG_PLL2CR1 0x8b8 |
| #define CPG_PLL3CR0 0x83c |
| #define CPG_PLL3CR1 0x8c0 |
| #define CPG_PLL4CR0 0x844 |
| #define CPG_PLL4CR1 0x8c8 |
| #define CPG_PLL6CR0 0x84c |
| #define CPG_PLL6CR1 0x8d8 |
| |
| #define CPG_PLLxCR0_KICK BIT(31) |
| #define CPG_PLLxCR0_NI GENMASK(27, 20) /* Integer mult. factor */ |
| #define CPG_PLLxCR0_SSMODE GENMASK(18, 16) /* PLL mode */ |
| #define CPG_PLLxCR0_SSMODE_FM BIT(18) /* Fractional Multiplication */ |
| #define CPG_PLLxCR0_SSMODE_DITH BIT(17) /* Frequency Dithering */ |
| #define CPG_PLLxCR0_SSMODE_CENT BIT(16) /* Center (vs. Down) Spread Dithering */ |
| #define CPG_PLLxCR0_SSFREQ GENMASK(14, 8) /* SSCG Modulation Frequency */ |
| #define CPG_PLLxCR0_SSDEPT GENMASK(6, 0) /* SSCG Modulation Depth */ |
| |
| #define SSMODE_FM BIT(2) /* Fractional Multiplication */ |
| #define SSMODE_DITHER BIT(1) /* Frequency Dithering */ |
| #define SSMODE_CENTER BIT(0) /* Center (vs. Down) Spread Dithering */ |
| |
| /* PLL Clocks */ |
| struct cpg_pll_clk { |
| struct clk_hw hw; |
| void __iomem *pllcr0_reg; |
| void __iomem *pllecr_reg; |
| 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; |
| |
| mult = FIELD_GET(CPG_PLLxCR0_NI, readl(pll_clk->pllcr0_reg)) + 1; |
| |
| return parent_rate * mult * 2; |
| } |
| |
| static int cpg_pll_clk_determine_rate(struct clk_hw *hw, |
| struct clk_rate_request *req) |
| { |
| unsigned int min_mult, max_mult, mult; |
| unsigned long prate; |
| |
| prate = req->best_parent_rate * 2; |
| min_mult = max(div64_ul(req->min_rate, prate), 1ULL); |
| max_mult = min(div64_ul(req->max_rate, prate), 256ULL); |
| 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; |
| u32 val; |
| |
| mult = DIV_ROUND_CLOSEST_ULL(rate, parent_rate * 2); |
| mult = clamp(mult, 1U, 256U); |
| |
| if (readl(pll_clk->pllcr0_reg) & CPG_PLLxCR0_KICK) |
| return -EBUSY; |
| |
| cpg_reg_modify(pll_clk->pllcr0_reg, CPG_PLLxCR0_NI, |
| FIELD_PREP(CPG_PLLxCR0_NI, mult - 1)); |
| |
| /* |
| * Set KICK bit in PLLxCR0 to update hardware setting and wait for |
| * clock change completion. |
| */ |
| cpg_reg_modify(pll_clk->pllcr0_reg, 0, CPG_PLLxCR0_KICK); |
| |
| /* |
| * Note: There is no HW information about the worst case latency. |
| * |
| * Using experimental measurements, it seems that no more than |
| * ~45 µs are needed, independently of the CPU rate. |
| * Since this value might be dependent on external xtal rate, pll |
| * rate or even the other emulation clocks rate, use 1000 as a |
| * "super" safe value. |
| */ |
| return readl_poll_timeout(pll_clk->pllecr_reg, val, |
| val & pll_clk->pllecr_pllst_mask, 0, 1000); |
| } |
| |
| 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 cr0_offset, |
| unsigned int cr1_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->pllcr0_reg = base + cr0_offset; |
| pll_clk->pllecr_reg = base + CPG_PLLECR; |
| pll_clk->pllecr_pllst_mask = CPG_PLLECR_PLLST(index); |
| |
| /* Disable Fractional Multiplication and Frequency Dithering */ |
| writel(0, base + cr1_offset); |
| cpg_reg_modify(pll_clk->pllcr0_reg, CPG_PLLxCR0_SSMODE, 0); |
| |
| clk = clk_register(NULL, &pll_clk->hw); |
| if (IS_ERR(clk)) |
| kfree(pll_clk); |
| |
| return clk; |
| } |
| /* |
| * Z0 Clock & Z1 Clock |
| */ |
| #define CPG_FRQCRB 0x00000804 |
| #define CPG_FRQCRB_KICK BIT(31) |
| #define CPG_FRQCRC0 0x00000808 |
| #define CPG_FRQCRC1 0x000008e0 |
| |
| 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) |
| { |
| 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 = CLK_SET_RATE_PARENT; |
| init.parent_names = &parent_name; |
| init.num_parents = 1; |
| |
| if (offset < 32) { |
| zclk->reg = reg + CPG_FRQCRC0; |
| } else { |
| zclk->reg = reg + CPG_FRQCRC1; |
| offset -= 32; |
| } |
| 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; |
| } |
| |
| /* |
| * RPC Clocks |
| */ |
| static const struct clk_div_table cpg_rpcsrc_div_table[] = { |
| { 0, 4 }, { 1, 6 }, { 2, 5 }, { 3, 6 }, { 0, 0 }, |
| }; |
| |
| struct clk * __init rcar_gen4_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_GEN4_MAIN: |
| div = cpg_pll_config->extal_div; |
| break; |
| |
| case CLK_TYPE_GEN4_PLL1: |
| mult = cpg_pll_config->pll1_mult; |
| div = cpg_pll_config->pll1_div; |
| break; |
| |
| case CLK_TYPE_GEN4_PLL2_VAR: |
| /* |
| * 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, CPG_PLL2CR0, CPG_PLL2CR1, 2); |
| |
| case CLK_TYPE_GEN4_PLL2: |
| mult = cpg_pll_config->pll2_mult; |
| div = cpg_pll_config->pll2_div; |
| break; |
| |
| case CLK_TYPE_GEN4_PLL3: |
| mult = cpg_pll_config->pll3_mult; |
| div = cpg_pll_config->pll3_div; |
| break; |
| |
| case CLK_TYPE_GEN4_PLL4: |
| mult = cpg_pll_config->pll4_mult; |
| div = cpg_pll_config->pll4_div; |
| break; |
| |
| case CLK_TYPE_GEN4_PLL5: |
| mult = cpg_pll_config->pll5_mult; |
| div = cpg_pll_config->pll5_div; |
| break; |
| |
| case CLK_TYPE_GEN4_PLL6: |
| mult = cpg_pll_config->pll6_mult; |
| div = cpg_pll_config->pll6_div; |
| break; |
| |
| case CLK_TYPE_GEN4_PLL2X_3X: |
| value = readl(base + core->offset); |
| mult = (((value >> 24) & 0x7f) + 1) * 2; |
| break; |
| |
| case CLK_TYPE_GEN4_Z: |
| return cpg_z_clk_register(core->name, __clk_get_name(parent), |
| base, core->div, core->offset); |
| |
| case CLK_TYPE_GEN4_SDSRC: |
| div = ((readl(base + SD0CKCR1) >> 29) & 0x03) + 4; |
| break; |
| |
| case CLK_TYPE_GEN4_SDH: |
| return cpg_sdh_clk_register(core->name, base + core->offset, |
| __clk_get_name(parent), notifiers); |
| |
| case CLK_TYPE_GEN4_SD: |
| return cpg_sd_clk_register(core->name, base + core->offset, |
| __clk_get_name(parent)); |
| |
| case CLK_TYPE_GEN4_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_GEN4_OSC: |
| /* |
| * Clock combining OSC EXTAL predivider and a fixed divider |
| */ |
| div = cpg_pll_config->osc_prediv * core->div; |
| break; |
| |
| case CLK_TYPE_GEN4_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_GEN4_RPC: |
| return cpg_rpc_clk_register(core->name, base + CPG_RPCCKCR, |
| __clk_get_name(parent), notifiers); |
| |
| case CLK_TYPE_GEN4_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_gen4_cpg_init(const struct rcar_gen4_cpg_pll_config *config, |
| unsigned int clk_extalr, u32 mode) |
| { |
| cpg_pll_config = config; |
| cpg_clk_extalr = clk_extalr; |
| cpg_mode = mode; |
| |
| return 0; |
| } |