--- /dev/null
+/*
+ * Copyright (c) 2014 MediaTek Inc.
+ * Author: James Liao <jamesjj.liao@mediatek.com>
+ *
+ * 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.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/io.h>
+#include <linux/slab.h>
+#include <linux/clkdev.h>
+#include <linux/delay.h>
+
+#include "clk-mtk.h"
+
+#define REG_CON0 0
+#define REG_CON1 4
+
+#define CON0_BASE_EN BIT(0)
+#define CON0_PWR_ON BIT(0)
+#define CON0_ISO_EN BIT(1)
+#define CON0_PCW_CHG BIT(31)
+
+#define AUDPLL_TUNER_EN BIT(31)
+
+#define POSTDIV_MASK 0x7
+#define INTEGER_BITS 7
+
+/*
+ * MediaTek PLLs are configured through their pcw value. The pcw value describes
+ * a divider in the PLL feedback loop which consists of 7 bits for the integer
+ * part and the remaining bits (if present) for the fractional part. Also they
+ * have a 3 bit power-of-two post divider.
+ */
+
+struct mtk_clk_pll {
+ struct clk_hw hw;
+ void __iomem *base_addr;
+ void __iomem *pd_addr;
+ void __iomem *pwr_addr;
+ void __iomem *tuner_addr;
+ void __iomem *pcw_addr;
+ const struct mtk_pll_data *data;
+};
+
+static inline struct mtk_clk_pll *to_mtk_clk_pll(struct clk_hw *hw)
+{
+ return container_of(hw, struct mtk_clk_pll, hw);
+}
+
+static int mtk_pll_is_prepared(struct clk_hw *hw)
+{
+ struct mtk_clk_pll *pll = to_mtk_clk_pll(hw);
+
+ return (readl(pll->base_addr + REG_CON0) & CON0_BASE_EN) != 0;
+}
+
+static unsigned long __mtk_pll_recalc_rate(struct mtk_clk_pll *pll, u32 fin,
+ u32 pcw, int postdiv)
+{
+ int pcwbits = pll->data->pcwbits;
+ int pcwfbits;
+ u64 vco;
+ u8 c = 0;
+
+ /* The fractional part of the PLL divider. */
+ pcwfbits = pcwbits > INTEGER_BITS ? pcwbits - INTEGER_BITS : 0;
+
+ vco = (u64)fin * pcw;
+
+ if (pcwfbits && (vco & GENMASK(pcwfbits - 1, 0)))
+ c = 1;
+
+ vco >>= pcwfbits;
+
+ if (c)
+ vco++;
+
+ return ((unsigned long)vco + postdiv - 1) / postdiv;
+}
+
+static void mtk_pll_set_rate_regs(struct mtk_clk_pll *pll, u32 pcw,
+ int postdiv)
+{
+ u32 con1, val;
+ int pll_en;
+
+ pll_en = readl(pll->base_addr + REG_CON0) & CON0_BASE_EN;
+
+ /* set postdiv */
+ val = readl(pll->pd_addr);
+ val &= ~(POSTDIV_MASK << pll->data->pd_shift);
+ val |= (ffs(postdiv) - 1) << pll->data->pd_shift;
+
+ /* postdiv and pcw need to set at the same time if on same register */
+ if (pll->pd_addr != pll->pcw_addr) {
+ writel(val, pll->pd_addr);
+ val = readl(pll->pcw_addr);
+ }
+
+ /* set pcw */
+ val &= ~GENMASK(pll->data->pcw_shift + pll->data->pcwbits - 1,
+ pll->data->pcw_shift);
+ val |= pcw << pll->data->pcw_shift;
+ writel(val, pll->pcw_addr);
+
+ con1 = readl(pll->base_addr + REG_CON1);
+
+ if (pll_en)
+ con1 |= CON0_PCW_CHG;
+
+ writel(con1, pll->base_addr + REG_CON1);
+ if (pll->tuner_addr)
+ writel(con1 + 1, pll->tuner_addr);
+
+ if (pll_en)
+ udelay(20);
+}
+
+/*
+ * mtk_pll_calc_values - calculate good values for a given input frequency.
+ * @pll: The pll
+ * @pcw: The pcw value (output)
+ * @postdiv: The post divider (output)
+ * @freq: The desired target frequency
+ * @fin: The input frequency
+ *
+ */
+static void mtk_pll_calc_values(struct mtk_clk_pll *pll, u32 *pcw, u32 *postdiv,
+ u32 freq, u32 fin)
+{
+ unsigned long fmin = 1000 * MHZ;
+ const struct mtk_pll_div_table *div_table = pll->data->div_table;
+ u64 _pcw;
+ u32 val;
+
+ if (freq > pll->data->fmax)
+ freq = pll->data->fmax;
+
+ if (div_table) {
+ if (freq > div_table[0].freq)
+ freq = div_table[0].freq;
+
+ for (val = 0; div_table[val + 1].freq != 0; val++) {
+ if (freq > div_table[val + 1].freq)
+ break;
+ }
+ *postdiv = 1 << val;
+ } else {
+ for (val = 0; val < 5; val++) {
+ *postdiv = 1 << val;
+ if ((u64)freq * *postdiv >= fmin)
+ break;
+ }
+ }
+
+ /* _pcw = freq * postdiv / fin * 2^pcwfbits */
+ _pcw = ((u64)freq << val) << (pll->data->pcwbits - INTEGER_BITS);
+ do_div(_pcw, fin);
+
+ *pcw = (u32)_pcw;
+}
+
+static int mtk_pll_set_rate(struct clk_hw *hw, unsigned long rate,
+ unsigned long parent_rate)
+{
+ struct mtk_clk_pll *pll = to_mtk_clk_pll(hw);
+ u32 pcw = 0;
+ u32 postdiv;
+
+ mtk_pll_calc_values(pll, &pcw, &postdiv, rate, parent_rate);
+ mtk_pll_set_rate_regs(pll, pcw, postdiv);
+
+ return 0;
+}
+
+static unsigned long mtk_pll_recalc_rate(struct clk_hw *hw,
+ unsigned long parent_rate)
+{
+ struct mtk_clk_pll *pll = to_mtk_clk_pll(hw);
+ u32 postdiv;
+ u32 pcw;
+
+ postdiv = (readl(pll->pd_addr) >> pll->data->pd_shift) & POSTDIV_MASK;
+ postdiv = 1 << postdiv;
+
+ pcw = readl(pll->pcw_addr) >> pll->data->pcw_shift;
+ pcw &= GENMASK(pll->data->pcwbits - 1, 0);
+
+ return __mtk_pll_recalc_rate(pll, parent_rate, pcw, postdiv);
+}
+
+static long mtk_pll_round_rate(struct clk_hw *hw, unsigned long rate,
+ unsigned long *prate)
+{
+ struct mtk_clk_pll *pll = to_mtk_clk_pll(hw);
+ u32 pcw = 0;
+ int postdiv;
+
+ mtk_pll_calc_values(pll, &pcw, &postdiv, rate, *prate);
+
+ return __mtk_pll_recalc_rate(pll, *prate, pcw, postdiv);
+}
+
+static int mtk_pll_prepare(struct clk_hw *hw)
+{
+ struct mtk_clk_pll *pll = to_mtk_clk_pll(hw);
+ u32 r;
+
+ r = readl(pll->pwr_addr) | CON0_PWR_ON;
+ writel(r, pll->pwr_addr);
+ udelay(1);
+
+ r = readl(pll->pwr_addr) & ~CON0_ISO_EN;
+ writel(r, pll->pwr_addr);
+ udelay(1);
+
+ r = readl(pll->base_addr + REG_CON0);
+ r |= pll->data->en_mask;
+ writel(r, pll->base_addr + REG_CON0);
+
+ if (pll->tuner_addr) {
+ r = readl(pll->tuner_addr) | AUDPLL_TUNER_EN;
+ writel(r, pll->tuner_addr);
+ }
+
+ udelay(20);
+
+ if (pll->data->flags & HAVE_RST_BAR) {
+ r = readl(pll->base_addr + REG_CON0);
+ r |= pll->data->rst_bar_mask;
+ writel(r, pll->base_addr + REG_CON0);
+ }
+
+ return 0;
+}
+
+static void mtk_pll_unprepare(struct clk_hw *hw)
+{
+ struct mtk_clk_pll *pll = to_mtk_clk_pll(hw);
+ u32 r;
+
+ if (pll->data->flags & HAVE_RST_BAR) {
+ r = readl(pll->base_addr + REG_CON0);
+ r &= ~pll->data->rst_bar_mask;
+ writel(r, pll->base_addr + REG_CON0);
+ }
+
+ if (pll->tuner_addr) {
+ r = readl(pll->tuner_addr) & ~AUDPLL_TUNER_EN;
+ writel(r, pll->tuner_addr);
+ }
+
+ r = readl(pll->base_addr + REG_CON0);
+ r &= ~CON0_BASE_EN;
+ writel(r, pll->base_addr + REG_CON0);
+
+ r = readl(pll->pwr_addr) | CON0_ISO_EN;
+ writel(r, pll->pwr_addr);
+
+ r = readl(pll->pwr_addr) & ~CON0_PWR_ON;
+ writel(r, pll->pwr_addr);
+}
+
+static const struct clk_ops mtk_pll_ops = {
+ .is_prepared = mtk_pll_is_prepared,
+ .prepare = mtk_pll_prepare,
+ .unprepare = mtk_pll_unprepare,
+ .recalc_rate = mtk_pll_recalc_rate,
+ .round_rate = mtk_pll_round_rate,
+ .set_rate = mtk_pll_set_rate,
+};
+
+static struct clk *mtk_clk_register_pll(const struct mtk_pll_data *data,
+ void __iomem *base)
+{
+ struct mtk_clk_pll *pll;
+ struct clk_init_data init = {};
+ struct clk *clk;
+ const char *parent_name = "clk26m";
+
+ pll = kzalloc(sizeof(*pll), GFP_KERNEL);
+ if (!pll)
+ return ERR_PTR(-ENOMEM);
+
+ pll->base_addr = base + data->reg;
+ pll->pwr_addr = base + data->pwr_reg;
+ pll->pd_addr = base + data->pd_reg;
+ pll->pcw_addr = base + data->pcw_reg;
+ if (data->tuner_reg)
+ pll->tuner_addr = base + data->tuner_reg;
+ pll->hw.init = &init;
+ pll->data = data;
+
+ init.name = data->name;
+ init.ops = &mtk_pll_ops;
+ init.parent_names = &parent_name;
+ init.num_parents = 1;
+
+ clk = clk_register(NULL, &pll->hw);
+
+ if (IS_ERR(clk))
+ kfree(pll);
+
+ return clk;
+}
+
+void __init mtk_clk_register_plls(struct device_node *node,
+ const struct mtk_pll_data *plls, int num_plls, struct clk_onecell_data *clk_data)
+{
+ void __iomem *base;
+ int i;
+ struct clk *clk;
+
+ base = of_iomap(node, 0);
+ if (!base) {
+ pr_err("%s(): ioremap failed\n", __func__);
+ return;
+ }
+
+ for (i = 0; i < num_plls; i++) {
+ const struct mtk_pll_data *pll = &plls[i];
+
+ clk = mtk_clk_register_pll(pll, base);
+
+ if (IS_ERR(clk)) {
+ pr_err("Failed to register clk %s: %ld\n",
+ pll->name, PTR_ERR(clk));
+ continue;
+ }
+
+ clk_data->clks[pll->id] = clk;
+ }
+}
Code Review / kvmfornfv.git / blobdiff