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author | Ulrich Hecht <ulrich.hecht+renesas@gmail.com> | 2015-02-26 17:42:07 +0100 |
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committer | Simon Horman <horms+renesas@verge.net.au> | 2015-02-27 09:49:25 +0900 |
commit | 6232c51cb370919b116e0aea38d12aa33aae2fa9 (patch) | |
tree | f4e6891de70a8ed1f95523250f60c3dbe2ba35c6 | |
parent | a5dc23f6896005a18629b5c1be0e39a9f6090bf5 (diff) | |
download | op-kernel-dev-6232c51cb370919b116e0aea38d12aa33aae2fa9.zip op-kernel-dev-6232c51cb370919b116e0aea38d12aa33aae2fa9.tar.gz |
ARM: shmobile: r8a7778: common clock framework CPG driver
Driver for the r8a7778's clocks that depend on the mode bits.
Signed-off-by: Ulrich Hecht <ulrich.hecht+renesas@gmail.com>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Acked-by: Michael Turquette <mturquette@linaro.org>
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>
-rw-r--r-- | Documentation/devicetree/bindings/clock/renesas,r8a7778-cpg-clocks.txt | 25 | ||||
-rw-r--r-- | drivers/clk/shmobile/Makefile | 1 | ||||
-rw-r--r-- | drivers/clk/shmobile/clk-r8a7778.c | 143 | ||||
-rw-r--r-- | include/linux/clk/shmobile.h | 1 |
4 files changed, 170 insertions, 0 deletions
diff --git a/Documentation/devicetree/bindings/clock/renesas,r8a7778-cpg-clocks.txt b/Documentation/devicetree/bindings/clock/renesas,r8a7778-cpg-clocks.txt new file mode 100644 index 0000000..2f3747f --- /dev/null +++ b/Documentation/devicetree/bindings/clock/renesas,r8a7778-cpg-clocks.txt @@ -0,0 +1,25 @@ +* Renesas R8A7778 Clock Pulse Generator (CPG) + +The CPG generates core clocks for the R8A7778. It includes two PLLs and +several fixed ratio dividers + +Required Properties: + + - compatible: Must be "renesas,r8a7778-cpg-clocks" + - reg: Base address and length of the memory resource used by the CPG + - #clock-cells: Must be 1 + - clock-output-names: The names of the clocks. Supported clocks are + "plla", "pllb", "b", "out", "p", "s", and "s1". + + +Example +------- + + cpg_clocks: cpg_clocks@ffc80000 { + compatible = "renesas,r8a7778-cpg-clocks"; + reg = <0xffc80000 0x80>; + #clock-cells = <1>; + clocks = <&extal_clk>; + clock-output-names = "plla", "pllb", "b", + "out", "p", "s", "s1"; + }; diff --git a/drivers/clk/shmobile/Makefile b/drivers/clk/shmobile/Makefile index 0689d7f..97c71c8 100644 --- a/drivers/clk/shmobile/Makefile +++ b/drivers/clk/shmobile/Makefile @@ -2,6 +2,7 @@ obj-$(CONFIG_ARCH_EMEV2) += clk-emev2.o obj-$(CONFIG_ARCH_R7S72100) += clk-rz.o obj-$(CONFIG_ARCH_R8A73A4) += clk-r8a73a4.o obj-$(CONFIG_ARCH_R8A7740) += clk-r8a7740.o +obj-$(CONFIG_ARCH_R8A7778) += clk-r8a7778.o obj-$(CONFIG_ARCH_R8A7779) += clk-r8a7779.o obj-$(CONFIG_ARCH_R8A7790) += clk-rcar-gen2.o obj-$(CONFIG_ARCH_R8A7791) += clk-rcar-gen2.o diff --git a/drivers/clk/shmobile/clk-r8a7778.c b/drivers/clk/shmobile/clk-r8a7778.c new file mode 100644 index 0000000..cb33b57 --- /dev/null +++ b/drivers/clk/shmobile/clk-r8a7778.c @@ -0,0 +1,143 @@ +/* + * r8a7778 Core CPG Clocks + * + * Copyright (C) 2014 Ulrich Hecht + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; version 2 of the License. + */ + +#include <linux/clk-provider.h> +#include <linux/clkdev.h> +#include <linux/clk/shmobile.h> +#include <linux/of_address.h> + +struct r8a7778_cpg { + struct clk_onecell_data data; + spinlock_t lock; + void __iomem *reg; +}; + +/* PLL multipliers per bits 11, 12, and 18 of MODEMR */ +struct { + unsigned long plla_mult; + unsigned long pllb_mult; +} r8a7778_rates[] __initdata = { + [0] = { 21, 21 }, + [1] = { 24, 24 }, + [2] = { 28, 28 }, + [3] = { 32, 32 }, + [5] = { 24, 21 }, + [6] = { 28, 21 }, + [7] = { 32, 24 }, +}; + +/* Clock dividers per bits 1 and 2 of MODEMR */ +struct { + const char *name; + unsigned int div[4]; +} r8a7778_divs[6] __initdata = { + { "b", { 12, 12, 16, 18 } }, + { "out", { 12, 12, 16, 18 } }, + { "p", { 16, 12, 16, 12 } }, + { "s", { 4, 3, 4, 3 } }, + { "s1", { 8, 6, 8, 6 } }, +}; + +static u32 cpg_mode_rates __initdata; +static u32 cpg_mode_divs __initdata; + +static struct clk * __init +r8a7778_cpg_register_clock(struct device_node *np, struct r8a7778_cpg *cpg, + const char *name) +{ + if (!strcmp(name, "plla")) { + return clk_register_fixed_factor(NULL, "plla", + of_clk_get_parent_name(np, 0), 0, + r8a7778_rates[cpg_mode_rates].plla_mult, 1); + } else if (!strcmp(name, "pllb")) { + return clk_register_fixed_factor(NULL, "pllb", + of_clk_get_parent_name(np, 0), 0, + r8a7778_rates[cpg_mode_rates].pllb_mult, 1); + } else { + unsigned int i; + + for (i = 0; i < ARRAY_SIZE(r8a7778_divs); i++) { + if (!strcmp(name, r8a7778_divs[i].name)) { + return clk_register_fixed_factor(NULL, + r8a7778_divs[i].name, + "plla", 0, 1, + r8a7778_divs[i].div[cpg_mode_divs]); + } + } + } + + return ERR_PTR(-EINVAL); +} + + +static void __init r8a7778_cpg_clocks_init(struct device_node *np) +{ + struct r8a7778_cpg *cpg; + struct clk **clks; + unsigned int i; + int num_clks; + + num_clks = of_property_count_strings(np, "clock-output-names"); + if (num_clks < 0) { + pr_err("%s: failed to count clocks\n", __func__); + return; + } + + cpg = kzalloc(sizeof(*cpg), GFP_KERNEL); + clks = kcalloc(num_clks, sizeof(*clks), GFP_KERNEL); + if (cpg == NULL || clks == NULL) { + /* We're leaking memory on purpose, there's no point in cleaning + * up as the system won't boot anyway. + */ + return; + } + + spin_lock_init(&cpg->lock); + + cpg->data.clks = clks; + cpg->data.clk_num = num_clks; + + cpg->reg = of_iomap(np, 0); + if (WARN_ON(cpg->reg == NULL)) + return; + + for (i = 0; i < num_clks; ++i) { + const char *name; + struct clk *clk; + + of_property_read_string_index(np, "clock-output-names", i, + &name); + + clk = r8a7778_cpg_register_clock(np, cpg, name); + if (IS_ERR(clk)) + pr_err("%s: failed to register %s %s clock (%ld)\n", + __func__, np->name, name, PTR_ERR(clk)); + else + cpg->data.clks[i] = clk; + } + + of_clk_add_provider(np, of_clk_src_onecell_get, &cpg->data); +} + +CLK_OF_DECLARE(r8a7778_cpg_clks, "renesas,r8a7778-cpg-clocks", + r8a7778_cpg_clocks_init); + +void __init r8a7778_clocks_init(u32 mode) +{ + BUG_ON(!(mode & BIT(19))); + + cpg_mode_rates = (!!(mode & BIT(18)) << 2) | + (!!(mode & BIT(12)) << 1) | + (!!(mode & BIT(11))); + cpg_mode_divs = (!!(mode & BIT(2)) << 1) | + (!!(mode & BIT(1))); + + of_clk_init(NULL); +} diff --git a/include/linux/clk/shmobile.h b/include/linux/clk/shmobile.h index 9f8a140..63a8159 100644 --- a/include/linux/clk/shmobile.h +++ b/include/linux/clk/shmobile.h @@ -16,6 +16,7 @@ #include <linux/types.h> +void r8a7778_clocks_init(u32 mode); void r8a7779_clocks_init(u32 mode); void rcar_gen2_clocks_init(u32 mode); |