From: Alexandre Belloni <alexandre.bell...@free-electrons.com> This is a clock driver for the simple PLLs found on Berlin SoCs. With repect to PLL registers and features, BG2/BG2CD and BG2Q are slightly different, e.g. different allowed VCO dividers and bit shifts.
Signed-off-by: Alexandre Belloni <alexandre.bell...@free-electrons.com> Signed-off-by: Sebastian Hesselbarth <sebastian.hesselba...@gmail.com> --- Cc: Mike Turquette <mturque...@linaro.org> Cc: Alexandre Belloni <alexandre.bell...@free-electrons.com> Cc: Antoine Tenart <antoine.ten...@free-electrons.com> Cc: linux-arm-ker...@lists.infradead.org Cc: linux-kernel@vger.kernel.org --- drivers/clk/berlin/Makefile | 2 +- drivers/clk/berlin/berlin2-pll.c | 171 +++++++++++++++++++++++++++++++++++++++ 2 files changed, 172 insertions(+), 1 deletion(-) create mode 100644 drivers/clk/berlin/berlin2-pll.c diff --git a/drivers/clk/berlin/Makefile b/drivers/clk/berlin/Makefile index 5905733fc7c7..9d3490e9782f 100644 --- a/drivers/clk/berlin/Makefile +++ b/drivers/clk/berlin/Makefile @@ -1 +1 @@ -obj-y += berlin2-avpll.o +obj-y += berlin2-avpll.o berlin2-pll.o diff --git a/drivers/clk/berlin/berlin2-pll.c b/drivers/clk/berlin/berlin2-pll.c new file mode 100644 index 000000000000..ca2805fffdf2 --- /dev/null +++ b/drivers/clk/berlin/berlin2-pll.c @@ -0,0 +1,171 @@ +/* + * Copyright (c) 2014 Marvell Technology Group Ltd. + * + * Alexandre Belloni <alexandre.bell...@free-electrons.com> + * Sebastian Hesselbarth <sebastian.hesselba...@gmail.com> + * + * This program is free software; you can redistribute it and/or modify it + * under the terms and conditions of the GNU General Public License, + * version 2, as published by the Free Software Foundation. + * + * This program is distributed in the hope 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. + * + * You should have received a copy of the GNU General Public License along with + * this program. If not, see <http://www.gnu.org/licenses/>. + */ +#include <linux/clk-provider.h> +#include <linux/io.h> +#include <linux/kernel.h> +#include <linux/of.h> +#include <linux/of_address.h> +#include <linux/slab.h> +#include <asm/div64.h> + +struct berlin2_pll_map { + const u8 vcodiv[16]; + u8 mult; + u8 fbdiv_shift; + u8 rfdiv_shift; + u8 divsel_shift; +}; + +struct berlin2_pll { + struct clk_hw hw; + void __iomem *base; + struct berlin2_pll_map map; +}; + +#define to_berlin2_pll(hw) container_of(hw, struct berlin2_pll, hw) + +#define SPLL_CTRL0 0x00 +#define SPLL_CTRL1 0x04 +#define SPLL_CTRL2 0x08 +#define SPLL_CTRL3 0x0c +#define SPLL_CTRL4 0x10 + +#define FBDIV_MASK 0x1ff +#define RFDIV_MASK 0x1f +#define DIVSEL_MASK 0xf + +/* + * The output frequency formula for the pll is: + * clkout = fbdiv / refdiv * parent / vcodiv + */ +static unsigned long +berlin2_pll_recalc_rate(struct clk_hw *hw, unsigned long parent_rate) +{ + struct berlin2_pll *pll = to_berlin2_pll(hw); + struct berlin2_pll_map *map = &pll->map; + u32 val, fbdiv, rfdiv, vcodivsel, vcodiv; + u64 rate = parent_rate; + + val = readl_relaxed(pll->base + SPLL_CTRL0); + fbdiv = (val >> map->fbdiv_shift) & FBDIV_MASK; + rfdiv = (val >> map->rfdiv_shift) & RFDIV_MASK; + if (rfdiv == 0) { + pr_warn("%s has zero rfdiv\n", __clk_get_name(hw->clk)); + rfdiv = 1; + } + + val = readl_relaxed(pll->base + SPLL_CTRL1); + vcodivsel = (val >> map->divsel_shift) & DIVSEL_MASK; + vcodiv = map->vcodiv[vcodivsel]; + if (vcodiv == 0) { + pr_warn("%s has zero vcodiv (index %d)\n", + __clk_get_name(hw->clk), vcodivsel); + vcodiv = 1; + } + + rate *= fbdiv * map->mult; + do_div(rate, rfdiv * vcodiv); + + return (unsigned long)rate; +} + +static const struct clk_ops berlin2_pll_ops = { + .recalc_rate = berlin2_pll_recalc_rate, +}; + +static struct clk * __init +berlin2_pll_register(const struct berlin2_pll_map *map, + void __iomem *base, const char *name, + const char *parent_name, unsigned long flags) +{ + struct clk_init_data init; + struct berlin2_pll *pll; + + pll = kzalloc(sizeof(*pll), GFP_KERNEL); + if (!pll) + return ERR_PTR(-ENOMEM); + + /* copy pll_map to allow __initconst */ + memcpy(&pll->map, map, sizeof(*map)); + pll->base = base; + pll->hw.init = &init; + init.name = name; + init.ops = &berlin2_pll_ops; + init.parent_names = &parent_name; + init.num_parents = 1; + init.flags = flags; + + return clk_register(NULL, &pll->hw); +} + +static const struct berlin2_pll_map bg2_pll_map __initconst = { + .vcodiv = {10, 15, 20, 25, 30, 40, 50, 60, 80}, + .mult = 10, + .fbdiv_shift = 6, + .rfdiv_shift = 1, + .divsel_shift = 7, +}; + +static const struct berlin2_pll_map bg2q_pll_map __initconst = { + .vcodiv = {1, 0, 2, 0, 3, 4, 0, 6, 8}, + .mult = 1, + .fbdiv_shift = 7, + .rfdiv_shift = 2, + .divsel_shift = 9, +}; + +static const struct of_device_id pll_matches[] __initconst = { + { .compatible = "marvell,berlin2-pll", .data = &bg2_pll_map }, + { .compatible = "marvell,berlin2q-pll", .data = &bg2q_pll_map }, + { } +}; + +static void __init berlin2_pll_of_setup(struct device_node *np) +{ + const struct of_device_id *match = of_match_node(pll_matches, np); + const struct berlin2_pll_map *map = match->data; + void __iomem *base; + struct clk *refclk; + struct clk *pll; + char *pll_name; + + base = of_iomap(np, 0); + if (!base) { + pr_err("%s: Unable to map pll register\n", np->full_name); + return; + } + + refclk = of_clk_get(np, 0); + if (IS_ERR(refclk)) { + pr_err("%s: Missing reference clock\n", np->full_name); + iounmap(base); + return; + } + + pll_name = of_clk_create_name(np); + pll = berlin2_pll_register(map, base, pll_name, + __clk_get_name(refclk), 0); + if (!IS_ERR(pll)) + of_clk_add_provider(np, of_clk_src_simple_get, pll); + + clk_put(refclk); + kfree(pll_name); +} +CLK_OF_DECLARE(berlin2_pll, "marvell,berlin2-pll", berlin2_pll_of_setup); +CLK_OF_DECLARE(berlin2q_pll, "marvell,berlin2q-pll", berlin2_pll_of_setup); -- 1.9.1 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
