From mboxrd@z Thu Jan 1 00:00:00 1970 From: Mike Turquette Date: Fri, 23 May 2014 20:39:00 +0000 Subject: Re: [PATCH v5] clk: shmobile: Add R8A7740-specific clock support Message-Id: <20140523203900.23136.74970@quantum> List-Id: References: <1400851635-27116-1-git-send-email-ulrich.hecht+renesas@gmail.com> In-Reply-To: <1400851635-27116-1-git-send-email-ulrich.hecht+renesas@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: linux-arm-kernel@lists.infradead.org Quoting Ulrich Hecht (2014-05-23 06:27:15) > Driver for the R8A7740's clocks that are too specific to be supported by a > generic driver. > > Signed-off-by: Ulrich Hecht > Acked-by: Geert Uytterhoeven > Acked-by: Laurent Pinchart Taken into clk-next. Regards, Mike > --- > > Changes since v4: > - marked bindings as experimental > - added acks > > Changes since v3: > - removed excess element in struct initializer > - use of_clk_get_parent_name() instead of hardcoding extal2 > - fixed wrong parent index for extalr > - reformatted register addresses > > Changes since v2: > - added missing clock extal2 > - removed redundant divider mask > > Changes since v1: > - reshuffled to include DT bindings and Makefile changes > > .../bindings/clock/renesas,r8a7740-cpg-clocks.txt | 41 +++++ > drivers/clk/shmobile/Makefile | 1 + > drivers/clk/shmobile/clk-r8a7740.c | 199 +++++++++++++++++++++ > 3 files changed, 241 insertions(+) > create mode 100644 Documentation/devicetree/bindings/clock/renesas,r8a7740-cpg-clocks.txt > create mode 100644 drivers/clk/shmobile/clk-r8a7740.c > > diff --git a/Documentation/devicetree/bindings/clock/renesas,r8a7740-cpg-clocks.txt b/Documentation/devicetree/bindings/clock/renesas,r8a7740-cpg-clocks.txt > new file mode 100644 > index 0000000..2c03302 > --- /dev/null > +++ b/Documentation/devicetree/bindings/clock/renesas,r8a7740-cpg-clocks.txt > @@ -0,0 +1,41 @@ > +These bindings should be considered EXPERIMENTAL for now. > + > +* Renesas R8A7740 Clock Pulse Generator (CPG) > + > +The CPG generates core clocks for the R8A7740 SoC. It includes three PLLs > +and several fixed ratio and variable ratio dividers. > + > +Required Properties: > + > + - compatible: Must be "renesas,r8a7740-cpg-clocks" > + > + - reg: Base address and length of the memory resource used by the CPG > + > + - clocks: Reference to the three parent clocks > + - #clock-cells: Must be 1 > + - clock-output-names: The names of the clocks. Supported clocks are > + "system", "pllc0", "pllc1", "pllc2", "r", "usb24s", "i", "zg", "b", > + "m1", "hp", "hpp", "usbp", "s", "zb", "m3", and "cp". > + > + - renesas,mode: board-specific settings of the MD_CK* bits > + > + > +Example > +------- > + > +cpg_clocks: cpg_clocks@e6150000 { > + compatible = "renesas,r8a7740-cpg-clocks"; > + reg = <0xe6150000 0x10000>; > + clocks = <&extal1_clk>, <&extal2_clk>, <&extalr_clk>; > + #clock-cells = <1>; > + clock-output-names = "system", "pllc0", "pllc1", > + "pllc2", "r", > + "usb24s", > + "i", "zg", "b", "m1", "hp", > + "hpp", "usbp", "s", "zb", "m3", > + "cp"; > +}; > + > +&cpg_clocks { > + renesas,mode = <0x05>; > +}; > diff --git a/drivers/clk/shmobile/Makefile b/drivers/clk/shmobile/Makefile > index 5404cb9..20388e8 100644 > --- a/drivers/clk/shmobile/Makefile > +++ b/drivers/clk/shmobile/Makefile > @@ -1,5 +1,6 @@ > obj-$(CONFIG_ARCH_EMEV2) += clk-emev2.o > obj-$(CONFIG_ARCH_R7S72100) += clk-rz.o > +obj-$(CONFIG_ARCH_R8A7740) += clk-r8a7740.o > obj-$(CONFIG_ARCH_R8A7790) += clk-rcar-gen2.o > obj-$(CONFIG_ARCH_R8A7791) += clk-rcar-gen2.o > obj-$(CONFIG_ARCH_SHMOBILE_MULTI) += clk-div6.o > diff --git a/drivers/clk/shmobile/clk-r8a7740.c b/drivers/clk/shmobile/clk-r8a7740.c > new file mode 100644 > index 0000000..1e2eaae > --- /dev/null > +++ b/drivers/clk/shmobile/clk-r8a7740.c > @@ -0,0 +1,199 @@ > +/* > + * r8a7740 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 > +#include > +#include > +#include > +#include > +#include > +#include > +#include > + > +struct r8a7740_cpg { > + struct clk_onecell_data data; > + spinlock_t lock; > + void __iomem *reg; > +}; > + > +#define CPG_FRQCRA 0x00 > +#define CPG_FRQCRB 0x04 > +#define CPG_PLLC2CR 0x2c > +#define CPG_USBCKCR 0x8c > +#define CPG_FRQCRC 0xe0 > + > +#define CLK_ENABLE_ON_INIT BIT(0) > + > +struct div4_clk { > + const char *name; > + unsigned int reg; > + unsigned int shift; > + int flags; > +}; > + > +static struct div4_clk div4_clks[] = { > + { "i", CPG_FRQCRA, 20, CLK_ENABLE_ON_INIT }, > + { "zg", CPG_FRQCRA, 16, CLK_ENABLE_ON_INIT }, > + { "b", CPG_FRQCRA, 8, CLK_ENABLE_ON_INIT }, > + { "m1", CPG_FRQCRA, 4, CLK_ENABLE_ON_INIT }, > + { "hp", CPG_FRQCRB, 4, 0 }, > + { "hpp", CPG_FRQCRC, 20, 0 }, > + { "usbp", CPG_FRQCRC, 16, 0 }, > + { "s", CPG_FRQCRC, 12, 0 }, > + { "zb", CPG_FRQCRC, 8, 0 }, > + { "m3", CPG_FRQCRC, 4, 0 }, > + { "cp", CPG_FRQCRC, 0, 0 }, > + { NULL, 0, 0, 0 }, > +}; > + > +static const struct clk_div_table div4_div_table[] = { > + { 0, 2 }, { 1, 3 }, { 2, 4 }, { 3, 6 }, { 4, 8 }, { 5, 12 }, > + { 6, 16 }, { 7, 18 }, { 8, 24 }, { 9, 32 }, { 10, 36 }, { 11, 48 }, > + { 13, 72 }, { 14, 96 }, { 0, 0 } > +}; > + > +static u32 cpg_mode __initdata; > + > +static struct clk * __init > +r8a7740_cpg_register_clock(struct device_node *np, struct r8a7740_cpg *cpg, > + const char *name) > +{ > + const struct clk_div_table *table = NULL; > + const char *parent_name; > + unsigned int shift, reg; > + unsigned int mult = 1; > + unsigned int div = 1; > + > + if (!strcmp(name, "r")) { > + switch (cpg_mode & (BIT(2) | BIT(1))) { > + case BIT(1) | BIT(2): > + /* extal1 */ > + parent_name = of_clk_get_parent_name(np, 0); > + div = 2048; > + break; > + case BIT(2): > + /* extal1 */ > + parent_name = of_clk_get_parent_name(np, 0); > + div = 1024; > + break; > + default: > + /* extalr */ > + parent_name = of_clk_get_parent_name(np, 2); > + break; > + } > + } else if (!strcmp(name, "system")) { > + parent_name = of_clk_get_parent_name(np, 0); > + if (cpg_mode & BIT(1)) > + div = 2; > + } else if (!strcmp(name, "pllc0")) { > + /* PLLC0/1 are configurable multiplier clocks. Register them as > + * fixed factor clocks for now as there's no generic multiplier > + * clock implementation and we currently have no need to change > + * the multiplier value. > + */ > + u32 value = clk_readl(cpg->reg + CPG_FRQCRC); > + parent_name = "system"; > + mult = ((value >> 24) & 0x7f) + 1; > + } else if (!strcmp(name, "pllc1")) { > + u32 value = clk_readl(cpg->reg + CPG_FRQCRA); > + parent_name = "system"; > + mult = ((value >> 24) & 0x7f) + 1; > + div = 2; > + } else if (!strcmp(name, "pllc2")) { > + u32 value = clk_readl(cpg->reg + CPG_PLLC2CR); > + parent_name = "system"; > + mult = ((value >> 24) & 0x3f) + 1; > + } else if (!strcmp(name, "usb24s")) { > + u32 value = clk_readl(cpg->reg + CPG_USBCKCR); > + if (value & BIT(7)) > + /* extal2 */ > + parent_name = of_clk_get_parent_name(np, 1); > + else > + parent_name = "system"; > + if (!(value & BIT(6))) > + div = 2; > + } else { > + struct div4_clk *c; > + for (c = div4_clks; c->name; c++) { > + if (!strcmp(name, c->name)) { > + parent_name = "pllc1"; > + table = div4_div_table; > + reg = c->reg; > + shift = c->shift; > + break; > + } > + } > + if (!c->name) > + return ERR_PTR(-EINVAL); > + } > + > + if (!table) { > + return clk_register_fixed_factor(NULL, name, parent_name, 0, > + mult, div); > + } else { > + return clk_register_divider_table(NULL, name, parent_name, 0, > + cpg->reg + reg, shift, 4, 0, > + table, &cpg->lock); > + } > +} > + > +static void __init r8a7740_cpg_clocks_init(struct device_node *np) > +{ > + struct r8a7740_cpg *cpg; > + struct clk **clks; > + unsigned int i; > + int num_clks; > + > + if (of_property_read_u32(np, "renesas,mode", &cpg_mode)) > + pr_warn("%s: missing renesas,mode property\n", __func__); > + > + 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 = kzalloc(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 = r8a7740_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(r8a7740_cpg_clks, "renesas,r8a7740-cpg-clocks", > + r8a7740_cpg_clocks_init); > -- > 1.8.4.5 >