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-rw-r--r--drivers/clk/pistachio/clk-pll.c510
1 files changed, 510 insertions, 0 deletions
diff --git a/drivers/clk/pistachio/clk-pll.c b/drivers/clk/pistachio/clk-pll.c
new file mode 100644
index 000000000..025b9df76
--- /dev/null
+++ b/drivers/clk/pistachio/clk-pll.c
@@ -0,0 +1,510 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2014 Google, Inc.
+ */
+
+#define pr_fmt(fmt) "%s: " fmt, __func__
+
+#include <linux/clk-provider.h>
+#include <linux/io.h>
+#include <linux/kernel.h>
+#include <linux/printk.h>
+#include <linux/slab.h>
+
+#include "clk.h"
+
+#define PLL_STATUS 0x0
+#define PLL_STATUS_LOCK BIT(0)
+
+#define PLL_CTRL1 0x4
+#define PLL_CTRL1_REFDIV_SHIFT 0
+#define PLL_CTRL1_REFDIV_MASK 0x3f
+#define PLL_CTRL1_FBDIV_SHIFT 6
+#define PLL_CTRL1_FBDIV_MASK 0xfff
+#define PLL_INT_CTRL1_POSTDIV1_SHIFT 18
+#define PLL_INT_CTRL1_POSTDIV1_MASK 0x7
+#define PLL_INT_CTRL1_POSTDIV2_SHIFT 21
+#define PLL_INT_CTRL1_POSTDIV2_MASK 0x7
+#define PLL_INT_CTRL1_PD BIT(24)
+#define PLL_INT_CTRL1_DSMPD BIT(25)
+#define PLL_INT_CTRL1_FOUTPOSTDIVPD BIT(26)
+#define PLL_INT_CTRL1_FOUTVCOPD BIT(27)
+
+#define PLL_CTRL2 0x8
+#define PLL_FRAC_CTRL2_FRAC_SHIFT 0
+#define PLL_FRAC_CTRL2_FRAC_MASK 0xffffff
+#define PLL_FRAC_CTRL2_POSTDIV1_SHIFT 24
+#define PLL_FRAC_CTRL2_POSTDIV1_MASK 0x7
+#define PLL_FRAC_CTRL2_POSTDIV2_SHIFT 27
+#define PLL_FRAC_CTRL2_POSTDIV2_MASK 0x7
+#define PLL_INT_CTRL2_BYPASS BIT(28)
+
+#define PLL_CTRL3 0xc
+#define PLL_FRAC_CTRL3_PD BIT(0)
+#define PLL_FRAC_CTRL3_DACPD BIT(1)
+#define PLL_FRAC_CTRL3_DSMPD BIT(2)
+#define PLL_FRAC_CTRL3_FOUTPOSTDIVPD BIT(3)
+#define PLL_FRAC_CTRL3_FOUT4PHASEPD BIT(4)
+#define PLL_FRAC_CTRL3_FOUTVCOPD BIT(5)
+
+#define PLL_CTRL4 0x10
+#define PLL_FRAC_CTRL4_BYPASS BIT(28)
+
+#define MIN_PFD 9600000UL
+#define MIN_VCO_LA 400000000UL
+#define MAX_VCO_LA 1600000000UL
+#define MIN_VCO_FRAC_INT 600000000UL
+#define MAX_VCO_FRAC_INT 1600000000UL
+#define MIN_VCO_FRAC_FRAC 600000000UL
+#define MAX_VCO_FRAC_FRAC 2400000000UL
+#define MIN_OUTPUT_LA 8000000UL
+#define MAX_OUTPUT_LA 1600000000UL
+#define MIN_OUTPUT_FRAC 12000000UL
+#define MAX_OUTPUT_FRAC 1600000000UL
+
+/* Fractional PLL operating modes */
+enum pll_mode {
+ PLL_MODE_FRAC,
+ PLL_MODE_INT,
+};
+
+struct pistachio_clk_pll {
+ struct clk_hw hw;
+ void __iomem *base;
+ struct pistachio_pll_rate_table *rates;
+ unsigned int nr_rates;
+};
+
+static inline u32 pll_readl(struct pistachio_clk_pll *pll, u32 reg)
+{
+ return readl(pll->base + reg);
+}
+
+static inline void pll_writel(struct pistachio_clk_pll *pll, u32 val, u32 reg)
+{
+ writel(val, pll->base + reg);
+}
+
+static inline void pll_lock(struct pistachio_clk_pll *pll)
+{
+ while (!(pll_readl(pll, PLL_STATUS) & PLL_STATUS_LOCK))
+ cpu_relax();
+}
+
+static inline u64 do_div_round_closest(u64 dividend, u64 divisor)
+{
+ dividend += divisor / 2;
+ return div64_u64(dividend, divisor);
+}
+
+static inline struct pistachio_clk_pll *to_pistachio_pll(struct clk_hw *hw)
+{
+ return container_of(hw, struct pistachio_clk_pll, hw);
+}
+
+static inline enum pll_mode pll_frac_get_mode(struct clk_hw *hw)
+{
+ struct pistachio_clk_pll *pll = to_pistachio_pll(hw);
+ u32 val;
+
+ val = pll_readl(pll, PLL_CTRL3) & PLL_FRAC_CTRL3_DSMPD;
+ return val ? PLL_MODE_INT : PLL_MODE_FRAC;
+}
+
+static inline void pll_frac_set_mode(struct clk_hw *hw, enum pll_mode mode)
+{
+ struct pistachio_clk_pll *pll = to_pistachio_pll(hw);
+ u32 val;
+
+ val = pll_readl(pll, PLL_CTRL3);
+ if (mode == PLL_MODE_INT)
+ val |= PLL_FRAC_CTRL3_DSMPD | PLL_FRAC_CTRL3_DACPD;
+ else
+ val &= ~(PLL_FRAC_CTRL3_DSMPD | PLL_FRAC_CTRL3_DACPD);
+
+ pll_writel(pll, val, PLL_CTRL3);
+}
+
+static struct pistachio_pll_rate_table *
+pll_get_params(struct pistachio_clk_pll *pll, unsigned long fref,
+ unsigned long fout)
+{
+ unsigned int i;
+
+ for (i = 0; i < pll->nr_rates; i++) {
+ if (pll->rates[i].fref == fref && pll->rates[i].fout == fout)
+ return &pll->rates[i];
+ }
+
+ return NULL;
+}
+
+static long pll_round_rate(struct clk_hw *hw, unsigned long rate,
+ unsigned long *parent_rate)
+{
+ struct pistachio_clk_pll *pll = to_pistachio_pll(hw);
+ unsigned int i;
+
+ for (i = 0; i < pll->nr_rates; i++) {
+ if (i > 0 && pll->rates[i].fref == *parent_rate &&
+ pll->rates[i].fout <= rate)
+ return pll->rates[i - 1].fout;
+ }
+
+ return pll->rates[0].fout;
+}
+
+static int pll_gf40lp_frac_enable(struct clk_hw *hw)
+{
+ struct pistachio_clk_pll *pll = to_pistachio_pll(hw);
+ u32 val;
+
+ val = pll_readl(pll, PLL_CTRL3);
+ val &= ~(PLL_FRAC_CTRL3_PD | PLL_FRAC_CTRL3_FOUTPOSTDIVPD |
+ PLL_FRAC_CTRL3_FOUT4PHASEPD | PLL_FRAC_CTRL3_FOUTVCOPD);
+ pll_writel(pll, val, PLL_CTRL3);
+
+ val = pll_readl(pll, PLL_CTRL4);
+ val &= ~PLL_FRAC_CTRL4_BYPASS;
+ pll_writel(pll, val, PLL_CTRL4);
+
+ pll_lock(pll);
+
+ return 0;
+}
+
+static void pll_gf40lp_frac_disable(struct clk_hw *hw)
+{
+ struct pistachio_clk_pll *pll = to_pistachio_pll(hw);
+ u32 val;
+
+ val = pll_readl(pll, PLL_CTRL3);
+ val |= PLL_FRAC_CTRL3_PD;
+ pll_writel(pll, val, PLL_CTRL3);
+}
+
+static int pll_gf40lp_frac_is_enabled(struct clk_hw *hw)
+{
+ struct pistachio_clk_pll *pll = to_pistachio_pll(hw);
+
+ return !(pll_readl(pll, PLL_CTRL3) & PLL_FRAC_CTRL3_PD);
+}
+
+static int pll_gf40lp_frac_set_rate(struct clk_hw *hw, unsigned long rate,
+ unsigned long parent_rate)
+{
+ struct pistachio_clk_pll *pll = to_pistachio_pll(hw);
+ struct pistachio_pll_rate_table *params;
+ int enabled = pll_gf40lp_frac_is_enabled(hw);
+ u64 val, vco, old_postdiv1, old_postdiv2;
+ const char *name = clk_hw_get_name(hw);
+
+ if (rate < MIN_OUTPUT_FRAC || rate > MAX_OUTPUT_FRAC)
+ return -EINVAL;
+
+ params = pll_get_params(pll, parent_rate, rate);
+ if (!params || !params->refdiv)
+ return -EINVAL;
+
+ /* calculate vco */
+ vco = params->fref;
+ vco *= (params->fbdiv << 24) + params->frac;
+ vco = div64_u64(vco, params->refdiv << 24);
+
+ if (vco < MIN_VCO_FRAC_FRAC || vco > MAX_VCO_FRAC_FRAC)
+ pr_warn("%s: VCO %llu is out of range %lu..%lu\n", name, vco,
+ MIN_VCO_FRAC_FRAC, MAX_VCO_FRAC_FRAC);
+
+ val = div64_u64(params->fref, params->refdiv);
+ if (val < MIN_PFD)
+ pr_warn("%s: PFD %llu is too low (min %lu)\n",
+ name, val, MIN_PFD);
+ if (val > vco / 16)
+ pr_warn("%s: PFD %llu is too high (max %llu)\n",
+ name, val, vco / 16);
+
+ val = pll_readl(pll, PLL_CTRL1);
+ val &= ~((PLL_CTRL1_REFDIV_MASK << PLL_CTRL1_REFDIV_SHIFT) |
+ (PLL_CTRL1_FBDIV_MASK << PLL_CTRL1_FBDIV_SHIFT));
+ val |= (params->refdiv << PLL_CTRL1_REFDIV_SHIFT) |
+ (params->fbdiv << PLL_CTRL1_FBDIV_SHIFT);
+ pll_writel(pll, val, PLL_CTRL1);
+
+ val = pll_readl(pll, PLL_CTRL2);
+
+ old_postdiv1 = (val >> PLL_FRAC_CTRL2_POSTDIV1_SHIFT) &
+ PLL_FRAC_CTRL2_POSTDIV1_MASK;
+ old_postdiv2 = (val >> PLL_FRAC_CTRL2_POSTDIV2_SHIFT) &
+ PLL_FRAC_CTRL2_POSTDIV2_MASK;
+ if (enabled &&
+ (params->postdiv1 != old_postdiv1 ||
+ params->postdiv2 != old_postdiv2))
+ pr_warn("%s: changing postdiv while PLL is enabled\n", name);
+
+ if (params->postdiv2 > params->postdiv1)
+ pr_warn("%s: postdiv2 should not exceed postdiv1\n", name);
+
+ val &= ~((PLL_FRAC_CTRL2_FRAC_MASK << PLL_FRAC_CTRL2_FRAC_SHIFT) |
+ (PLL_FRAC_CTRL2_POSTDIV1_MASK <<
+ PLL_FRAC_CTRL2_POSTDIV1_SHIFT) |
+ (PLL_FRAC_CTRL2_POSTDIV2_MASK <<
+ PLL_FRAC_CTRL2_POSTDIV2_SHIFT));
+ val |= (params->frac << PLL_FRAC_CTRL2_FRAC_SHIFT) |
+ (params->postdiv1 << PLL_FRAC_CTRL2_POSTDIV1_SHIFT) |
+ (params->postdiv2 << PLL_FRAC_CTRL2_POSTDIV2_SHIFT);
+ pll_writel(pll, val, PLL_CTRL2);
+
+ /* set operating mode */
+ if (params->frac)
+ pll_frac_set_mode(hw, PLL_MODE_FRAC);
+ else
+ pll_frac_set_mode(hw, PLL_MODE_INT);
+
+ if (enabled)
+ pll_lock(pll);
+
+ return 0;
+}
+
+static unsigned long pll_gf40lp_frac_recalc_rate(struct clk_hw *hw,
+ unsigned long parent_rate)
+{
+ struct pistachio_clk_pll *pll = to_pistachio_pll(hw);
+ u64 val, prediv, fbdiv, frac, postdiv1, postdiv2, rate;
+
+ val = pll_readl(pll, PLL_CTRL1);
+ prediv = (val >> PLL_CTRL1_REFDIV_SHIFT) & PLL_CTRL1_REFDIV_MASK;
+ fbdiv = (val >> PLL_CTRL1_FBDIV_SHIFT) & PLL_CTRL1_FBDIV_MASK;
+
+ val = pll_readl(pll, PLL_CTRL2);
+ postdiv1 = (val >> PLL_FRAC_CTRL2_POSTDIV1_SHIFT) &
+ PLL_FRAC_CTRL2_POSTDIV1_MASK;
+ postdiv2 = (val >> PLL_FRAC_CTRL2_POSTDIV2_SHIFT) &
+ PLL_FRAC_CTRL2_POSTDIV2_MASK;
+ frac = (val >> PLL_FRAC_CTRL2_FRAC_SHIFT) & PLL_FRAC_CTRL2_FRAC_MASK;
+
+ /* get operating mode (int/frac) and calculate rate accordingly */
+ rate = parent_rate;
+ if (pll_frac_get_mode(hw) == PLL_MODE_FRAC)
+ rate *= (fbdiv << 24) + frac;
+ else
+ rate *= (fbdiv << 24);
+
+ rate = do_div_round_closest(rate, (prediv * postdiv1 * postdiv2) << 24);
+
+ return rate;
+}
+
+static const struct clk_ops pll_gf40lp_frac_ops = {
+ .enable = pll_gf40lp_frac_enable,
+ .disable = pll_gf40lp_frac_disable,
+ .is_enabled = pll_gf40lp_frac_is_enabled,
+ .recalc_rate = pll_gf40lp_frac_recalc_rate,
+ .round_rate = pll_round_rate,
+ .set_rate = pll_gf40lp_frac_set_rate,
+};
+
+static const struct clk_ops pll_gf40lp_frac_fixed_ops = {
+ .enable = pll_gf40lp_frac_enable,
+ .disable = pll_gf40lp_frac_disable,
+ .is_enabled = pll_gf40lp_frac_is_enabled,
+ .recalc_rate = pll_gf40lp_frac_recalc_rate,
+};
+
+static int pll_gf40lp_laint_enable(struct clk_hw *hw)
+{
+ struct pistachio_clk_pll *pll = to_pistachio_pll(hw);
+ u32 val;
+
+ val = pll_readl(pll, PLL_CTRL1);
+ val &= ~(PLL_INT_CTRL1_PD |
+ PLL_INT_CTRL1_FOUTPOSTDIVPD | PLL_INT_CTRL1_FOUTVCOPD);
+ pll_writel(pll, val, PLL_CTRL1);
+
+ val = pll_readl(pll, PLL_CTRL2);
+ val &= ~PLL_INT_CTRL2_BYPASS;
+ pll_writel(pll, val, PLL_CTRL2);
+
+ pll_lock(pll);
+
+ return 0;
+}
+
+static void pll_gf40lp_laint_disable(struct clk_hw *hw)
+{
+ struct pistachio_clk_pll *pll = to_pistachio_pll(hw);
+ u32 val;
+
+ val = pll_readl(pll, PLL_CTRL1);
+ val |= PLL_INT_CTRL1_PD;
+ pll_writel(pll, val, PLL_CTRL1);
+}
+
+static int pll_gf40lp_laint_is_enabled(struct clk_hw *hw)
+{
+ struct pistachio_clk_pll *pll = to_pistachio_pll(hw);
+
+ return !(pll_readl(pll, PLL_CTRL1) & PLL_INT_CTRL1_PD);
+}
+
+static int pll_gf40lp_laint_set_rate(struct clk_hw *hw, unsigned long rate,
+ unsigned long parent_rate)
+{
+ struct pistachio_clk_pll *pll = to_pistachio_pll(hw);
+ struct pistachio_pll_rate_table *params;
+ int enabled = pll_gf40lp_laint_is_enabled(hw);
+ u32 val, vco, old_postdiv1, old_postdiv2;
+ const char *name = clk_hw_get_name(hw);
+
+ if (rate < MIN_OUTPUT_LA || rate > MAX_OUTPUT_LA)
+ return -EINVAL;
+
+ params = pll_get_params(pll, parent_rate, rate);
+ if (!params || !params->refdiv)
+ return -EINVAL;
+
+ vco = div_u64(params->fref * params->fbdiv, params->refdiv);
+ if (vco < MIN_VCO_LA || vco > MAX_VCO_LA)
+ pr_warn("%s: VCO %u is out of range %lu..%lu\n", name, vco,
+ MIN_VCO_LA, MAX_VCO_LA);
+
+ val = div_u64(params->fref, params->refdiv);
+ if (val < MIN_PFD)
+ pr_warn("%s: PFD %u is too low (min %lu)\n",
+ name, val, MIN_PFD);
+ if (val > vco / 16)
+ pr_warn("%s: PFD %u is too high (max %u)\n",
+ name, val, vco / 16);
+
+ val = pll_readl(pll, PLL_CTRL1);
+
+ old_postdiv1 = (val >> PLL_INT_CTRL1_POSTDIV1_SHIFT) &
+ PLL_INT_CTRL1_POSTDIV1_MASK;
+ old_postdiv2 = (val >> PLL_INT_CTRL1_POSTDIV2_SHIFT) &
+ PLL_INT_CTRL1_POSTDIV2_MASK;
+ if (enabled &&
+ (params->postdiv1 != old_postdiv1 ||
+ params->postdiv2 != old_postdiv2))
+ pr_warn("%s: changing postdiv while PLL is enabled\n", name);
+
+ if (params->postdiv2 > params->postdiv1)
+ pr_warn("%s: postdiv2 should not exceed postdiv1\n", name);
+
+ val &= ~((PLL_CTRL1_REFDIV_MASK << PLL_CTRL1_REFDIV_SHIFT) |
+ (PLL_CTRL1_FBDIV_MASK << PLL_CTRL1_FBDIV_SHIFT) |
+ (PLL_INT_CTRL1_POSTDIV1_MASK << PLL_INT_CTRL1_POSTDIV1_SHIFT) |
+ (PLL_INT_CTRL1_POSTDIV2_MASK << PLL_INT_CTRL1_POSTDIV2_SHIFT));
+ val |= (params->refdiv << PLL_CTRL1_REFDIV_SHIFT) |
+ (params->fbdiv << PLL_CTRL1_FBDIV_SHIFT) |
+ (params->postdiv1 << PLL_INT_CTRL1_POSTDIV1_SHIFT) |
+ (params->postdiv2 << PLL_INT_CTRL1_POSTDIV2_SHIFT);
+ pll_writel(pll, val, PLL_CTRL1);
+
+ if (enabled)
+ pll_lock(pll);
+
+ return 0;
+}
+
+static unsigned long pll_gf40lp_laint_recalc_rate(struct clk_hw *hw,
+ unsigned long parent_rate)
+{
+ struct pistachio_clk_pll *pll = to_pistachio_pll(hw);
+ u32 val, prediv, fbdiv, postdiv1, postdiv2;
+ u64 rate = parent_rate;
+
+ val = pll_readl(pll, PLL_CTRL1);
+ prediv = (val >> PLL_CTRL1_REFDIV_SHIFT) & PLL_CTRL1_REFDIV_MASK;
+ fbdiv = (val >> PLL_CTRL1_FBDIV_SHIFT) & PLL_CTRL1_FBDIV_MASK;
+ postdiv1 = (val >> PLL_INT_CTRL1_POSTDIV1_SHIFT) &
+ PLL_INT_CTRL1_POSTDIV1_MASK;
+ postdiv2 = (val >> PLL_INT_CTRL1_POSTDIV2_SHIFT) &
+ PLL_INT_CTRL1_POSTDIV2_MASK;
+
+ rate *= fbdiv;
+ rate = do_div_round_closest(rate, prediv * postdiv1 * postdiv2);
+
+ return rate;
+}
+
+static const struct clk_ops pll_gf40lp_laint_ops = {
+ .enable = pll_gf40lp_laint_enable,
+ .disable = pll_gf40lp_laint_disable,
+ .is_enabled = pll_gf40lp_laint_is_enabled,
+ .recalc_rate = pll_gf40lp_laint_recalc_rate,
+ .round_rate = pll_round_rate,
+ .set_rate = pll_gf40lp_laint_set_rate,
+};
+
+static const struct clk_ops pll_gf40lp_laint_fixed_ops = {
+ .enable = pll_gf40lp_laint_enable,
+ .disable = pll_gf40lp_laint_disable,
+ .is_enabled = pll_gf40lp_laint_is_enabled,
+ .recalc_rate = pll_gf40lp_laint_recalc_rate,
+};
+
+static struct clk *pll_register(const char *name, const char *parent_name,
+ unsigned long flags, void __iomem *base,
+ enum pistachio_pll_type type,
+ struct pistachio_pll_rate_table *rates,
+ unsigned int nr_rates)
+{
+ struct pistachio_clk_pll *pll;
+ struct clk_init_data init;
+ struct clk *clk;
+
+ pll = kzalloc(sizeof(*pll), GFP_KERNEL);
+ if (!pll)
+ return ERR_PTR(-ENOMEM);
+
+ init.name = name;
+ init.flags = flags | CLK_GET_RATE_NOCACHE;
+ init.parent_names = &parent_name;
+ init.num_parents = 1;
+
+ switch (type) {
+ case PLL_GF40LP_FRAC:
+ if (rates)
+ init.ops = &pll_gf40lp_frac_ops;
+ else
+ init.ops = &pll_gf40lp_frac_fixed_ops;
+ break;
+ case PLL_GF40LP_LAINT:
+ if (rates)
+ init.ops = &pll_gf40lp_laint_ops;
+ else
+ init.ops = &pll_gf40lp_laint_fixed_ops;
+ break;
+ default:
+ pr_err("Unrecognized PLL type %u\n", type);
+ kfree(pll);
+ return ERR_PTR(-EINVAL);
+ }
+
+ pll->hw.init = &init;
+ pll->base = base;
+ pll->rates = rates;
+ pll->nr_rates = nr_rates;
+
+ clk = clk_register(NULL, &pll->hw);
+ if (IS_ERR(clk))
+ kfree(pll);
+
+ return clk;
+}
+
+void pistachio_clk_register_pll(struct pistachio_clk_provider *p,
+ struct pistachio_pll *pll,
+ unsigned int num)
+{
+ struct clk *clk;
+ unsigned int i;
+
+ for (i = 0; i < num; i++) {
+ clk = pll_register(pll[i].name, pll[i].parent,
+ 0, p->base + pll[i].reg_base,
+ pll[i].type, pll[i].rates,
+ pll[i].nr_rates);
+ p->clk_data.clks[pll[i].id] = clk;
+ }
+}