diff options
author | 2016-04-11 10:41:07 +0300 | |
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committer | 2016-04-13 08:17:18 +0300 | |
commit | e09b41010ba33a20a87472ee821fa407a5b8da36 (patch) | |
tree | d10dc367189862e7ca5c592f033dc3726e1df4e3 /kernel/drivers/clk/mediatek/clk-pll.c | |
parent | f93b97fd65072de626c074dbe099a1fff05ce060 (diff) |
These changes are the raw update to linux-4.4.6-rt14. Kernel sources
are taken from kernel.org, and rt patch from the rt wiki download page.
During the rebasing, the following patch collided:
Force tick interrupt and get rid of softirq magic(I70131fb85).
Collisions have been removed because its logic was found on the
source already.
Change-Id: I7f57a4081d9deaa0d9ccfc41a6c8daccdee3b769
Signed-off-by: José Pekkarinen <jose.pekkarinen@nokia.com>
Diffstat (limited to 'kernel/drivers/clk/mediatek/clk-pll.c')
-rw-r--r-- | kernel/drivers/clk/mediatek/clk-pll.c | 342 |
1 files changed, 342 insertions, 0 deletions
diff --git a/kernel/drivers/clk/mediatek/clk-pll.c b/kernel/drivers/clk/mediatek/clk-pll.c new file mode 100644 index 000000000..966cab134 --- /dev/null +++ b/kernel/drivers/clk/mediatek/clk-pll.c @@ -0,0 +1,342 @@ +/* + * 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; + } +} |