diff options
Diffstat (limited to 'drivers/clk/imx/clk-pllv3.c')
-rw-r--r-- | drivers/clk/imx/clk-pllv3.c | 331 |
1 files changed, 331 insertions, 0 deletions
diff --git a/drivers/clk/imx/clk-pllv3.c b/drivers/clk/imx/clk-pllv3.c new file mode 100644 index 000000000000..641ebc508920 --- /dev/null +++ b/drivers/clk/imx/clk-pllv3.c @@ -0,0 +1,331 @@ +/* + * Copyright 2012 Freescale Semiconductor, Inc. + * Copyright 2012 Linaro Ltd. + * + * The code contained herein is licensed under the GNU General Public + * License. You may obtain a copy of the GNU General Public License + * Version 2 or later at the following locations: + * + * http://www.opensource.org/licenses/gpl-license.html + * http://www.gnu.org/copyleft/gpl.html + */ + +#include <linux/clk.h> +#include <linux/clk-provider.h> +#include <linux/delay.h> +#include <linux/io.h> +#include <linux/slab.h> +#include <linux/jiffies.h> +#include <linux/err.h> +#include "clk.h" + +#define PLL_NUM_OFFSET 0x10 +#define PLL_DENOM_OFFSET 0x20 + +#define BM_PLL_POWER (0x1 << 12) +#define BM_PLL_LOCK (0x1 << 31) + +/** + * struct clk_pllv3 - IMX PLL clock version 3 + * @clk_hw: clock source + * @base: base address of PLL registers + * @powerup_set: set POWER bit to power up the PLL + * @div_mask: mask of divider bits + * @div_shift: shift of divider bits + * + * IMX PLL clock version 3, found on i.MX6 series. Divider for pllv3 + * is actually a multiplier, and always sits at bit 0. + */ +struct clk_pllv3 { + struct clk_hw hw; + void __iomem *base; + bool powerup_set; + u32 div_mask; + u32 div_shift; +}; + +#define to_clk_pllv3(_hw) container_of(_hw, struct clk_pllv3, hw) + +static int clk_pllv3_wait_lock(struct clk_pllv3 *pll) +{ + unsigned long timeout = jiffies + msecs_to_jiffies(10); + u32 val = readl_relaxed(pll->base) & BM_PLL_POWER; + + /* No need to wait for lock when pll is not powered up */ + if ((pll->powerup_set && !val) || (!pll->powerup_set && val)) + return 0; + + /* Wait for PLL to lock */ + do { + if (readl_relaxed(pll->base) & BM_PLL_LOCK) + break; + if (time_after(jiffies, timeout)) + break; + usleep_range(50, 500); + } while (1); + + return readl_relaxed(pll->base) & BM_PLL_LOCK ? 0 : -ETIMEDOUT; +} + +static int clk_pllv3_prepare(struct clk_hw *hw) +{ + struct clk_pllv3 *pll = to_clk_pllv3(hw); + u32 val; + + val = readl_relaxed(pll->base); + if (pll->powerup_set) + val |= BM_PLL_POWER; + else + val &= ~BM_PLL_POWER; + writel_relaxed(val, pll->base); + + return clk_pllv3_wait_lock(pll); +} + +static void clk_pllv3_unprepare(struct clk_hw *hw) +{ + struct clk_pllv3 *pll = to_clk_pllv3(hw); + u32 val; + + val = readl_relaxed(pll->base); + if (pll->powerup_set) + val &= ~BM_PLL_POWER; + else + val |= BM_PLL_POWER; + writel_relaxed(val, pll->base); +} + +static unsigned long clk_pllv3_recalc_rate(struct clk_hw *hw, + unsigned long parent_rate) +{ + struct clk_pllv3 *pll = to_clk_pllv3(hw); + u32 div = (readl_relaxed(pll->base) >> pll->div_shift) & pll->div_mask; + + return (div == 1) ? parent_rate * 22 : parent_rate * 20; +} + +static long clk_pllv3_round_rate(struct clk_hw *hw, unsigned long rate, + unsigned long *prate) +{ + unsigned long parent_rate = *prate; + + return (rate >= parent_rate * 22) ? parent_rate * 22 : + parent_rate * 20; +} + +static int clk_pllv3_set_rate(struct clk_hw *hw, unsigned long rate, + unsigned long parent_rate) +{ + struct clk_pllv3 *pll = to_clk_pllv3(hw); + u32 val, div; + + if (rate == parent_rate * 22) + div = 1; + else if (rate == parent_rate * 20) + div = 0; + else + return -EINVAL; + + val = readl_relaxed(pll->base); + val &= ~(pll->div_mask << pll->div_shift); + val |= (div << pll->div_shift); + writel_relaxed(val, pll->base); + + return clk_pllv3_wait_lock(pll); +} + +static const struct clk_ops clk_pllv3_ops = { + .prepare = clk_pllv3_prepare, + .unprepare = clk_pllv3_unprepare, + .recalc_rate = clk_pllv3_recalc_rate, + .round_rate = clk_pllv3_round_rate, + .set_rate = clk_pllv3_set_rate, +}; + +static unsigned long clk_pllv3_sys_recalc_rate(struct clk_hw *hw, + unsigned long parent_rate) +{ + struct clk_pllv3 *pll = to_clk_pllv3(hw); + u32 div = readl_relaxed(pll->base) & pll->div_mask; + + return parent_rate * div / 2; +} + +static long clk_pllv3_sys_round_rate(struct clk_hw *hw, unsigned long rate, + unsigned long *prate) +{ + unsigned long parent_rate = *prate; + unsigned long min_rate = parent_rate * 54 / 2; + unsigned long max_rate = parent_rate * 108 / 2; + u32 div; + + if (rate > max_rate) + rate = max_rate; + else if (rate < min_rate) + rate = min_rate; + div = rate * 2 / parent_rate; + + return parent_rate * div / 2; +} + +static int clk_pllv3_sys_set_rate(struct clk_hw *hw, unsigned long rate, + unsigned long parent_rate) +{ + struct clk_pllv3 *pll = to_clk_pllv3(hw); + unsigned long min_rate = parent_rate * 54 / 2; + unsigned long max_rate = parent_rate * 108 / 2; + u32 val, div; + + if (rate < min_rate || rate > max_rate) + return -EINVAL; + + div = rate * 2 / parent_rate; + val = readl_relaxed(pll->base); + val &= ~pll->div_mask; + val |= div; + writel_relaxed(val, pll->base); + + return clk_pllv3_wait_lock(pll); +} + +static const struct clk_ops clk_pllv3_sys_ops = { + .prepare = clk_pllv3_prepare, + .unprepare = clk_pllv3_unprepare, + .recalc_rate = clk_pllv3_sys_recalc_rate, + .round_rate = clk_pllv3_sys_round_rate, + .set_rate = clk_pllv3_sys_set_rate, +}; + +static unsigned long clk_pllv3_av_recalc_rate(struct clk_hw *hw, + unsigned long parent_rate) +{ + struct clk_pllv3 *pll = to_clk_pllv3(hw); + u32 mfn = readl_relaxed(pll->base + PLL_NUM_OFFSET); + u32 mfd = readl_relaxed(pll->base + PLL_DENOM_OFFSET); + u32 div = readl_relaxed(pll->base) & pll->div_mask; + + return (parent_rate * div) + ((parent_rate / mfd) * mfn); +} + +static long clk_pllv3_av_round_rate(struct clk_hw *hw, unsigned long rate, + unsigned long *prate) +{ + unsigned long parent_rate = *prate; + unsigned long min_rate = parent_rate * 27; + unsigned long max_rate = parent_rate * 54; + u32 div; + u32 mfn, mfd = 1000000; + s64 temp64; + + if (rate > max_rate) + rate = max_rate; + else if (rate < min_rate) + rate = min_rate; + + div = rate / parent_rate; + temp64 = (u64) (rate - div * parent_rate); + temp64 *= mfd; + do_div(temp64, parent_rate); + mfn = temp64; + + return parent_rate * div + parent_rate / mfd * mfn; +} + +static int clk_pllv3_av_set_rate(struct clk_hw *hw, unsigned long rate, + unsigned long parent_rate) +{ + struct clk_pllv3 *pll = to_clk_pllv3(hw); + unsigned long min_rate = parent_rate * 27; + unsigned long max_rate = parent_rate * 54; + u32 val, div; + u32 mfn, mfd = 1000000; + s64 temp64; + + if (rate < min_rate || rate > max_rate) + return -EINVAL; + + div = rate / parent_rate; + temp64 = (u64) (rate - div * parent_rate); + temp64 *= mfd; + do_div(temp64, parent_rate); + mfn = temp64; + + val = readl_relaxed(pll->base); + val &= ~pll->div_mask; + val |= div; + writel_relaxed(val, pll->base); + writel_relaxed(mfn, pll->base + PLL_NUM_OFFSET); + writel_relaxed(mfd, pll->base + PLL_DENOM_OFFSET); + + return clk_pllv3_wait_lock(pll); +} + +static const struct clk_ops clk_pllv3_av_ops = { + .prepare = clk_pllv3_prepare, + .unprepare = clk_pllv3_unprepare, + .recalc_rate = clk_pllv3_av_recalc_rate, + .round_rate = clk_pllv3_av_round_rate, + .set_rate = clk_pllv3_av_set_rate, +}; + +static unsigned long clk_pllv3_enet_recalc_rate(struct clk_hw *hw, + unsigned long parent_rate) +{ + return 500000000; +} + +static const struct clk_ops clk_pllv3_enet_ops = { + .prepare = clk_pllv3_prepare, + .unprepare = clk_pllv3_unprepare, + .recalc_rate = clk_pllv3_enet_recalc_rate, +}; + +struct clk *imx_clk_pllv3(enum imx_pllv3_type type, const char *name, + const char *parent_name, void __iomem *base, + u32 div_mask) +{ + struct clk_pllv3 *pll; + const struct clk_ops *ops; + struct clk *clk; + struct clk_init_data init; + + pll = kzalloc(sizeof(*pll), GFP_KERNEL); + if (!pll) + return ERR_PTR(-ENOMEM); + + switch (type) { + case IMX_PLLV3_SYS: + ops = &clk_pllv3_sys_ops; + break; + case IMX_PLLV3_USB_VF610: + pll->div_shift = 1; + case IMX_PLLV3_USB: + ops = &clk_pllv3_ops; + pll->powerup_set = true; + break; + case IMX_PLLV3_AV: + ops = &clk_pllv3_av_ops; + break; + case IMX_PLLV3_ENET: + ops = &clk_pllv3_enet_ops; + break; + default: + ops = &clk_pllv3_ops; + } + pll->base = base; + pll->div_mask = div_mask; + + init.name = name; + init.ops = ops; + init.flags = 0; + init.parent_names = &parent_name; + init.num_parents = 1; + + pll->hw.init = &init; + + clk = clk_register(NULL, &pll->hw); + if (IS_ERR(clk)) + kfree(pll); + + return clk; +} |