From mboxrd@z Thu Jan 1 00:00:00 1970 From: Mike Turquette Subject: Re: [PATCH v11] clk: add MOXA ART SoCs clock driver Date: Thu, 13 Mar 2014 13:27:58 -0700 Message-ID: <20140313202758.12081.26697@quantum> References: <1390308261-4026-1-git-send-email-jonas.jensen@gmail.com> <1390907351-28426-1-git-send-email-jonas.jensen@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <1390907351-28426-1-git-send-email-jonas.jensen@gmail.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=m.gmane.org@lists.infradead.org Cc: mark.rutland@arm.com, devicetree@vger.kernel.org, adam.jaremko@gmail.com, linux-kernel@vger.kernel.org, tomasz.figa@gmail.com, arm@kernel.org, Sudeep.Holla@arm.com, sylvester.nawrocki@gmail.com, Jonas Jensen , linux-arm-kernel@lists.infradead.org List-Id: devicetree@vger.kernel.org Quoting Jonas Jensen (2014-01-28 03:09:11) > MOXA ART SoCs allow to determine PLL output and APB frequencies > by reading registers holding multiplier and divisor information. > > Add a clock driver for this SoC. > > Signed-off-by: Jonas Jensen Taken into clk-next. Regards, Mike > --- > > Notes: > Thanks for the replies, > > Changes since v10: > > 1. add clock-specifier to DT binding description > 2. remove local variable "rate" > 3. add local variable "parent_name" > 4. use clk_register_fixed_factor() instead of clk_register_fixed_rate() > 5. remove flag CLK_IS_ROOT > > Applies to next-20140128 > > .../bindings/clock/moxa,moxart-clock.txt | 48 +++++++++++ > drivers/clk/Makefile | 1 + > drivers/clk/clk-moxart.c | 97 ++++++++++++++++++++++ > 3 files changed, 146 insertions(+) > create mode 100644 Documentation/devicetree/bindings/clock/moxa,moxart-clock.txt > create mode 100644 drivers/clk/clk-moxart.c > > diff --git a/Documentation/devicetree/bindings/clock/moxa,moxart-clock.txt b/Documentation/devicetree/bindings/clock/moxa,moxart-clock.txt > new file mode 100644 > index 0000000..fedea84 > --- /dev/null > +++ b/Documentation/devicetree/bindings/clock/moxa,moxart-clock.txt > @@ -0,0 +1,48 @@ > +Device Tree Clock bindings for arch-moxart > + > +This binding uses the common clock binding[1]. > + > +[1] Documentation/devicetree/bindings/clock/clock-bindings.txt > + > +MOXA ART SoCs allow to determine PLL output and APB frequencies > +by reading registers holding multiplier and divisor information. > + > + > +PLL: > + > +Required properties: > +- compatible : Must be "moxa,moxart-pll-clock" > +- #clock-cells : Should be 0 > +- reg : Should contain registers location and length > +- clocks : Should contain phandle + clock-specifier for the parent clock > + > +Optional properties: > +- clock-output-names : Should contain clock name > + > + > +APB: > + > +Required properties: > +- compatible : Must be "moxa,moxart-apb-clock" > +- #clock-cells : Should be 0 > +- reg : Should contain registers location and length > +- clocks : Should contain phandle + clock-specifier for the parent clock > + > +Optional properties: > +- clock-output-names : Should contain clock name > + > + > +For example: > + > + clk_pll: clk_pll@98100000 { > + compatible = "moxa,moxart-pll-clock"; > + #clock-cells = <0>; > + reg = <0x98100000 0x34>; > + }; > + > + clk_apb: clk_apb@98100000 { > + compatible = "moxa,moxart-apb-clock"; > + #clock-cells = <0>; > + reg = <0x98100000 0x34>; > + clocks = <&clk_pll>; > + }; > diff --git a/drivers/clk/Makefile b/drivers/clk/Makefile > index 0faf730..7940d0c 100644 > --- a/drivers/clk/Makefile > +++ b/drivers/clk/Makefile > @@ -12,6 +12,7 @@ obj-$(CONFIG_COMMON_CLK) += clk-composite.o > # SoCs specific > obj-$(CONFIG_ARCH_BCM2835) += clk-bcm2835.o > obj-$(CONFIG_ARCH_EFM32) += clk-efm32gg.o > +obj-$(CONFIG_ARCH_MOXART) += clk-moxart.o > obj-$(CONFIG_ARCH_NOMADIK) += clk-nomadik.o > obj-$(CONFIG_ARCH_HIGHBANK) += clk-highbank.o > obj-$(CONFIG_ARCH_HI3xxx) += hisilicon/ > diff --git a/drivers/clk/clk-moxart.c b/drivers/clk/clk-moxart.c > new file mode 100644 > index 0000000..30a3b69 > --- /dev/null > +++ b/drivers/clk/clk-moxart.c > @@ -0,0 +1,97 @@ > +/* > + * MOXA ART SoCs clock driver. > + * > + * Copyright (C) 2013 Jonas Jensen > + * > + * Jonas Jensen > + * > + * This file is licensed under the terms of the GNU General Public > + * License version 2. This program is licensed "as is" without any > + * warranty of any kind, whether express or implied. > + */ > + > +#include > +#include > +#include > +#include > + > +void __init moxart_of_pll_clk_init(struct device_node *node) > +{ > + static void __iomem *base; > + struct clk *clk, *ref_clk; > + unsigned int mul; > + const char *name = node->name; > + const char *parent_name; > + > + of_property_read_string(node, "clock-output-names", &name); > + parent_name = of_clk_get_parent_name(node, 0); > + > + base = of_iomap(node, 0); > + if (!base) { > + pr_err("%s: of_iomap failed\n", node->full_name); > + return; > + } > + > + mul = readl(base + 0x30) >> 3 & 0x3f; > + iounmap(base); > + > + ref_clk = of_clk_get(node, 0); > + if (IS_ERR(ref_clk)) { > + pr_err("%s: of_clk_get failed\n", node->full_name); > + return; > + } > + > + clk = clk_register_fixed_factor(NULL, name, parent_name, 0, mul, 1); > + if (IS_ERR(clk)) { > + pr_err("%s: failed to register clock\n", node->full_name); > + return; > + } > + > + clk_register_clkdev(clk, NULL, name); > + of_clk_add_provider(node, of_clk_src_simple_get, clk); > +} > +CLK_OF_DECLARE(moxart_pll_clock, "moxa,moxart-pll-clock", > + moxart_of_pll_clk_init); > + > +void __init moxart_of_apb_clk_init(struct device_node *node) > +{ > + static void __iomem *base; > + struct clk *clk, *pll_clk; > + unsigned int div, val; > + unsigned int div_idx[] = { 2, 3, 4, 6, 8}; > + const char *name = node->name; > + const char *parent_name; > + > + of_property_read_string(node, "clock-output-names", &name); > + parent_name = of_clk_get_parent_name(node, 0); > + > + base = of_iomap(node, 0); > + if (!base) { > + pr_err("%s: of_iomap failed\n", node->full_name); > + return; > + } > + > + val = readl(base + 0xc) >> 4 & 0x7; > + iounmap(base); > + > + if (val > 4) > + val = 0; > + div = div_idx[val] * 2; > + > + pll_clk = of_clk_get(node, 0); > + if (IS_ERR(pll_clk)) { > + pr_err("%s: of_clk_get failed\n", node->full_name); > + return; > + } > + > + clk = clk_register_fixed_factor(NULL, name, parent_name, 0, 1, div); > + if (IS_ERR(clk)) { > + pr_err("%s: failed to register clock\n", node->full_name); > + return; > + } > + > + clk_register_clkdev(clk, NULL, name); > + of_clk_add_provider(node, of_clk_src_simple_get, clk); > +} > +CLK_OF_DECLARE(moxart_apb_clock, "moxa,moxart-apb-clock", > + moxart_of_apb_clk_init); > -- > 1.8.2.1 >