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Tue, 19 Mar 2013 15:44:12 +0000 (UTC) Received: from SJ-ITEXEDGE02.altera.priv.altera.com (66.35.236.232) by TX2EHSMHS020.bigfish.com (10.9.99.120) with Microsoft SMTP Server (TLS) id 14.1.225.23; Tue, 19 Mar 2013 15:44:11 +0000 Received: from sj-mail01.altera.com (137.57.1.6) by SJ-ITEXEDGE02.altera.priv.altera.com (66.35.236.232) with Microsoft SMTP Server id 8.3.298.1; Tue, 19 Mar 2013 08:34:55 -0700 Received: from linux-builds1.altera.com (linux-builds1.altera.com [137.57.188.121]) by sj-mail01.altera.com (8.13.7+Sun/8.13.7) with ESMTP id r2JFi4nc011868; Tue, 19 Mar 2013 08:44:09 -0700 (PDT) From: To: Subject: [PATCHv2 2/2] ARM: socfpga: Add clock entries into device tree Date: Tue, 19 Mar 2013 10:45:36 -0500 Message-ID: <1363707936-17769-2-git-send-email-dinguyen@altera.com> X-Mailer: git-send-email 1.7.9.5 In-Reply-To: <1363707936-17769-1-git-send-email-dinguyen@altera.com> References: <1363707936-17769-1-git-send-email-dinguyen@altera.com> MIME-Version: 1.0 X-OriginatorOrg: altera.com X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20130319_114416_561963_4CAF2494 X-CRM114-Status: GOOD ( 20.65 ) X-Spam-Score: -4.2 (----) X-Spam-Report: SpamAssassin version 3.3.2 on merlin.infradead.org summary: Content analysis details: (-4.2 points) pts rule name description ---- ---------------------- -------------------------------------------------- -2.3 RCVD_IN_DNSWL_MED RBL: Sender listed at http://www.dnswl.org/, medium trust [65.55.88.13 listed in list.dnswl.org] -0.0 SPF_PASS SPF: sender matches SPF record -1.9 BAYES_00 BODY: Bayes spam probability is 0 to 1% [score: 0.0000] Cc: dinh.linux@gmail.com, arnd@arndb.de, pavel@denx.de, Dinh Nguyen , olof@lixom.net, linux-arm-kernel@lists.infradead.org X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org From: Dinh Nguyen Adds the main PLL clock groups for SOCFPGA into device tree file so that the clock framework to query the clock and clock rates appropriately. $cat /sys/kernel/debug/clk/clk_summary clock enable_cnt prepare_cnt rate --------------------------------------------------------------------- osc1 2 2 25000000 sdram_pll 0 0 400000000 s2f_usr2_clk 0 0 66666666 ddr_dq_clk 0 0 200000000 ddr_2x_dqs_clk 0 0 400000000 ddr_dqs_clk 0 0 200000000 periph_pll 2 2 500000000 s2f_usr1_clk 0 0 50000000 per_base_clk 4 4 100000000 per_nand_mmc_clk 0 0 25000000 per_qsi_clk 0 0 250000000 emac1_clk 1 1 125000000 emac0_clk 0 0 125000000 main_pll 1 1 1600000000 cfg_s2f_usr0_clk 0 0 100000000 main_nand_sdmmc_clk 0 0 100000000 main_qspi_clk 0 0 400000000 dbg_base_clk 0 0 400000000 mainclk 0 0 400000000 mpuclk 1 1 800000000 smp_twd 1 1 200000000 Signed-off-by: Dinh Nguyen v2: - Add copyright from Calxeda for clk.c - Add device tree "fixed-divider" for clocks with fixed dividers - Fix space and tab issues --- .../bindings/arm/altera/socfpga-clk-manager.txt | 11 ++ .../devicetree/bindings/clock/altr_socfpga.txt | 18 ++ arch/arm/boot/dts/socfpga.dtsi | 157 +++++++++++++++++ arch/arm/boot/dts/socfpga_cyclone5.dts | 8 + arch/arm/boot/dts/socfpga_vt.dts | 8 + arch/arm/mach-socfpga/socfpga.c | 6 + drivers/clk/socfpga/clk.c | 179 +++++++++++++++++--- 7 files changed, 366 insertions(+), 21 deletions(-) create mode 100644 Documentation/devicetree/bindings/arm/altera/socfpga-clk-manager.txt create mode 100644 Documentation/devicetree/bindings/clock/altr_socfpga.txt diff --git a/Documentation/devicetree/bindings/arm/altera/socfpga-clk-manager.txt b/Documentation/devicetree/bindings/arm/altera/socfpga-clk-manager.txt new file mode 100644 index 0000000..2c28f1d --- /dev/null +++ b/Documentation/devicetree/bindings/arm/altera/socfpga-clk-manager.txt @@ -0,0 +1,11 @@ +Altera SOCFPGA Clock Manager + +Required properties: +- compatible : "altr,clk-mgr" +- reg : Should contain base address and length for Clock Manager + +Example: + clkmgr@ffd04000 { + compatible = "altr,clk-mgr"; + reg = <0xffd04000 0x1000>; + }; diff --git a/Documentation/devicetree/bindings/clock/altr_socfpga.txt b/Documentation/devicetree/bindings/clock/altr_socfpga.txt new file mode 100644 index 0000000..bd0c841 --- /dev/null +++ b/Documentation/devicetree/bindings/clock/altr_socfpga.txt @@ -0,0 +1,18 @@ +Device Tree Clock bindings for Altera's SoCFPGA platform + +This binding uses the common clock binding[1]. + +[1] Documentation/devicetree/bindings/clock/clock-bindings.txt + +Required properties: +- compatible : shall be one of the following: + "altr,socfpga-pll-clock" - for a PLL clock + "altr,socfpga-perip-clock" - The peripheral clock divided from the + PLL clock. +- reg : shall be the control register offset from CLOCK_MANAGER's base for the clock. +- clocks : shall be the input parent clock phandle for the clock. This is + either an oscillator or a pll output. +- #clock-cells : from common clock binding, shall be set to 0. + +Optional properties: +- fixed-divider : If clocks have a fixed divider value, use this property. diff --git a/arch/arm/boot/dts/socfpga.dtsi b/arch/arm/boot/dts/socfpga.dtsi index 7e8769b..16a6e13 100644 --- a/arch/arm/boot/dts/socfpga.dtsi +++ b/arch/arm/boot/dts/socfpga.dtsi @@ -81,6 +81,163 @@ }; }; + clkmgr@ffd04000 { + compatible = "altr,clk-mgr"; + reg = <0xffd04000 0x1000>; + + clocks { + #address-cells = <1>; + #size-cells = <0>; + + osc: osc1 { + #clock-cells = <0>; + compatible = "fixed-clock"; + }; + + main_pll: main_pll { + #address-cells = <1>; + #size-cells = <0>; + #clock-cells = <0>; + compatible = "altr,socfpga-pll-clock"; + clocks = <&osc>; + reg = <0x40>; + + mpuclk: mpuclk { + #clock-cells = <0>; + compatible = "altr,socfpga-perip-clk"; + clocks = <&main_pll>; + fixed-divider = <2>; + reg = <0x48>; + }; + + mainclk: mainclk { + #clock-cells = <0>; + compatible = "altr,socfpga-perip-clk"; + clocks = <&main_pll>; + fixed-divider = <4>; + reg = <0x4C>; + }; + + dbg_base_clk: dbg_base_clk { + #clock-cells = <0>; + compatible = "altr,socfpga-perip-clk"; + clocks = <&main_pll>; + fixed-divider = <4>; + reg = <0x50>; + }; + + main_qspi_clk: main_qspi_clk { + #clock-cells = <0>; + compatible = "altr,socfpga-perip-clk"; + clocks = <&main_pll>; + reg = <0x54>; + }; + + main_nand_sdmmc_clk: main_nand_sdmmc_clk { + #clock-cells = <0>; + compatible = "altr,socfpga-perip-clk"; + clocks = <&main_pll>; + reg = <0x58>; + }; + + cfg_s2f_usr0_clk: cfg_s2f_usr0_clk { + #clock-cells = <0>; + compatible = "altr,socfpga-perip-clk"; + clocks = <&main_pll>; + reg = <0x5C>; + }; + }; + + periph_pll: periph_pll { + #address-cells = <1>; + #size-cells = <0>; + #clock-cells = <0>; + compatible = "altr,socfpga-pll-clock"; + clocks = <&osc>; + reg = <0x80>; + + emac0_clk: emac0_clk { + #clock-cells = <0>; + compatible = "altr,socfpga-perip-clk"; + clocks = <&periph_pll>; + reg = <0x88>; + }; + + emac1_clk: emac1_clk { + #clock-cells = <0>; + compatible = "altr,socfpga-perip-clk"; + clocks = <&periph_pll>; + reg = <0x8C>; + }; + + per_qspi_clk: per_qsi_clk { + #clock-cells = <0>; + compatible = "altr,socfpga-perip-clk"; + clocks = <&periph_pll>; + reg = <0x90>; + }; + + per_nand_mmc_clk: per_nand_mmc_clk { + #clock-cells = <0>; + compatible = "altr,socfpga-perip-clk"; + clocks = <&periph_pll>; + reg = <0x94>; + }; + + per_base_clk: per_base_clk { + #clock-cells = <0>; + compatible = "altr,socfpga-perip-clk"; + clocks = <&periph_pll>; + reg = <0x98>; + }; + + s2f_usr1_clk: s2f_usr1_clk { + #clock-cells = <0>; + compatible = "altr,socfpga-perip-clk"; + clocks = <&periph_pll>; + reg = <0x9C>; + }; + }; + + sdram_pll: sdram_pll { + #address-cells = <1>; + #size-cells = <0>; + #clock-cells = <0>; + compatible = "altr,socfpga-pll-clock"; + clocks = <&osc>; + reg = <0xC0>; + + ddr_dqs_clk: ddr_dqs_clk { + #clock-cells = <0>; + compatible = "altr,socfpga-perip-clk"; + clocks = <&sdram_pll>; + reg = <0xC8>; + }; + + ddr_2x_dqs_clk: ddr_2x_dqs_clk { + #clock-cells = <0>; + compatible = "altr,socfpga-perip-clk"; + clocks = <&sdram_pll>; + reg = <0xCC>; + }; + + ddr_dq_clk: ddr_dq_clk { + #clock-cells = <0>; + compatible = "altr,socfpga-perip-clk"; + clocks = <&sdram_pll>; + reg = <0xD0>; + }; + + s2f_usr2_clk: s2f_usr2_clk { + #clock-cells = <0>; + compatible = "altr,socfpga-perip-clk"; + clocks = <&sdram_pll>; + reg = <0xD4>; + }; + }; + }; + }; + gmac0: stmmac@ff700000 { compatible = "altr,socfpga-stmmac", "snps,dwmac-3.70a", "snps,dwmac"; reg = <0xff700000 0x2000>; diff --git a/arch/arm/boot/dts/socfpga_cyclone5.dts b/arch/arm/boot/dts/socfpga_cyclone5.dts index 3ae8a83..2495958 100644 --- a/arch/arm/boot/dts/socfpga_cyclone5.dts +++ b/arch/arm/boot/dts/socfpga_cyclone5.dts @@ -33,6 +33,14 @@ }; soc { + clkmgr@ffd04000 { + clocks { + osc1 { + clock-frequency = <25000000>; + }; + }; + }; + timer0@ffc08000 { clock-frequency = <100000000>; }; diff --git a/arch/arm/boot/dts/socfpga_vt.dts b/arch/arm/boot/dts/socfpga_vt.dts index 1036eba..0bf035d 100644 --- a/arch/arm/boot/dts/socfpga_vt.dts +++ b/arch/arm/boot/dts/socfpga_vt.dts @@ -33,6 +33,14 @@ }; soc { + clkmgr@ffd04000 { + clocks { + osc1 { + clock-frequency = <10000000>; + }; + }; + }; + timer0@ffc08000 { clock-frequency = <7000000>; }; diff --git a/arch/arm/mach-socfpga/socfpga.c b/arch/arm/mach-socfpga/socfpga.c index b41a945..856625a 100644 --- a/arch/arm/mach-socfpga/socfpga.c +++ b/arch/arm/mach-socfpga/socfpga.c @@ -15,6 +15,7 @@ * along with this program. If not, see . */ #include +#include #include #include #include @@ -29,6 +30,7 @@ void __iomem *socfpga_scu_base_addr = ((void __iomem *)(SOCFPGA_SCU_VIRT_BASE)); void __iomem *sys_manager_base_addr; void __iomem *rst_manager_base_addr; +void __iomem *clk_mgr_base_addr; unsigned long cpu1start_addr; static struct map_desc scu_io_desc __initdata = { @@ -77,6 +79,9 @@ void __init socfpga_sysmgr_init(void) np = of_find_compatible_node(NULL, NULL, "altr,rst-mgr"); rst_manager_base_addr = of_iomap(np, 0); + + np = of_find_compatible_node(NULL, NULL, "altr,clk-mgr"); + clk_mgr_base_addr = of_iomap(np, 0); } static void __init socfpga_init_irq(void) @@ -102,6 +107,7 @@ static void __init socfpga_cyclone5_init(void) { l2x0_of_init(0, ~0UL); of_platform_populate(NULL, of_default_bus_match_table, NULL, NULL); + of_clk_init(NULL); socfpga_init_clocks(); } diff --git a/drivers/clk/socfpga/clk.c b/drivers/clk/socfpga/clk.c index 2c855a6..da6b461 100644 --- a/drivers/clk/socfpga/clk.c +++ b/drivers/clk/socfpga/clk.c @@ -1,5 +1,6 @@ /* - * Copyright (C) 2012 Altera Corporation + * Copyright 2011-2012 Calxeda, Inc. + * Copyright (C) 2012-2013 Altera Corporation * * 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 @@ -11,41 +12,177 @@ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * + * Based from clk-highbank.c + * * You should have received a copy of the GNU General Public License * along with this program. If not, see . */ #include #include #include +#include +#include -#define SOCFPGA_OSC1_CLK 10000000 -#define SOCFPGA_MPU_CLK 800000000 -#define SOCFPGA_MAIN_QSPI_CLK 432000000 -#define SOCFPGA_MAIN_NAND_SDMMC_CLK 250000000 -#define SOCFPGA_S2F_USR_CLK 125000000 +/* Clock Manager offsets */ +#define CLKMGR_CTRL 0x0 +#define CLKMGR_BYPASS 0x4 -void __init socfpga_init_clocks(void) +/* Clock bypass bits */ +#define MAINPLL_BYPASS (1<<0) +#define SDRAMPLL_BYPASS (1<<1) +#define SDRAMPLL_SRC_BYPASS (1<<2) +#define PERPLL_BYPASS (1<<3) +#define PERPLL_SRC_BYPASS (1<<4) + +#define SOCFPGA_PLL_BG_PWRDWN 0x00000001 +#define SOCFPGA_PLL_EXT_ENA 0x00000002 +#define SOCFPGA_PLL_PWR_DOWN 0x00000004 +#define SOCFPGA_PLL_DIVF_MASK 0x0000FFF8 +#define SOCFPGA_PLL_DIVF_SHIFT 3 +#define SOCFPGA_PLL_DIVQ_MASK 0x003F0000 +#define SOCFPGA_PLL_DIVQ_SHIFT 15 + +extern void __iomem *clk_mgr_base_addr; + +struct socfpga_clk { + struct clk_hw hw; + void __iomem *reg; + char *parent_name; + char *clk_name; +}; +#define to_socfpga_clk(p) container_of(p, struct socfpga_clk, hw) + +static int clk_pll_enable(struct clk_hw *hwclk) +{ + struct socfpga_clk *socfpgaclk = to_socfpga_clk(hwclk); + u32 reg; + + reg = readl(socfpgaclk->reg); + reg |= SOCFPGA_PLL_EXT_ENA; + writel(reg, socfpgaclk->reg); + + return 0; +} + +static void clk_pll_disable(struct clk_hw *hwclk) { + struct socfpga_clk *socfpgaclk = to_socfpga_clk(hwclk); + u32 reg; + + reg = readl(socfpgaclk->reg); + reg &= ~SOCFPGA_PLL_EXT_ENA; + writel(reg, socfpgaclk->reg); +} + +static unsigned long clk_pll_recalc_rate(struct clk_hw *hwclk, + unsigned long parent_rate) +{ + struct socfpga_clk *socfpgaclk = to_socfpga_clk(hwclk); + unsigned long divf, divq, vco_freq, reg; + unsigned long bypass; + + reg = readl(socfpgaclk->reg); + bypass = readl(clk_mgr_base_addr + CLKMGR_BYPASS); + if (bypass & MAINPLL_BYPASS) + return parent_rate; + + divf = (reg & SOCFPGA_PLL_DIVF_MASK) >> SOCFPGA_PLL_DIVF_SHIFT; + divq = (reg & SOCFPGA_PLL_DIVQ_MASK) >> SOCFPGA_PLL_DIVQ_SHIFT; + vco_freq = parent_rate * (divf + 1); + return vco_freq / (1 << divq); +} + + +static const struct clk_ops clk_pll_ops = { + .enable = clk_pll_enable, + .disable = clk_pll_disable, + .recalc_rate = clk_pll_recalc_rate, +}; + +static unsigned long clk_periclk_recalc_rate(struct clk_hw *hwclk, + unsigned long parent_rate) +{ + struct socfpga_clk *socfpgaclk = to_socfpga_clk(hwclk); + u32 div; + + if (socfpgaclk->fixed_div) + div = socfpgaclk->fixed_div; + else + div = ((readl(socfpgaclk->reg) & 0x1ff) + 1); + + return parent_rate / div; +} + +static const struct clk_ops periclk_ops = { + .recalc_rate = clk_periclk_recalc_rate, +}; + +static __init struct clk *socfpga_clk_init(struct device_node *node, const struct clk_ops *ops) +{ + u32 reg; struct clk *clk; + struct socfpga_clk *socfpga_clk; + const char *clk_name = node->name; + const char *parent_name; + struct clk_init_data init; + int rc; + u32 fixed_div; + + rc = of_property_read_u32(node, "reg", ®); + if (WARN_ON(rc)) + return NULL; + + socfpga_clk = kzalloc(sizeof(*socfpga_clk), GFP_KERNEL); + if (WARN_ON(!socfpga_clk)) + return NULL; + + socfpga_clk->reg = clk_mgr_base_addr + reg; - clk = clk_register_fixed_rate(NULL, "osc1_clk", NULL, CLK_IS_ROOT, SOCFPGA_OSC1_CLK); - clk_register_clkdev(clk, "osc1_clk", NULL); + rc = of_property_read_u32(node, "fixed-divider", &fixed_div); + if (rc) + socfpga_clk->fixed_div = 0; + else + socfpga_clk->fixed_div = fixed_div; - clk = clk_register_fixed_rate(NULL, "mpu_clk", NULL, CLK_IS_ROOT, SOCFPGA_MPU_CLK); - clk_register_clkdev(clk, "mpu_clk", NULL); + of_property_read_string(node, "clock-output-names", &clk_name); - clk = clk_register_fixed_rate(NULL, "main_clk", NULL, CLK_IS_ROOT, SOCFPGA_MPU_CLK/2); - clk_register_clkdev(clk, "main_clk", NULL); + init.name = clk_name; + init.ops = ops; + init.flags = 0; + parent_name = of_clk_get_parent_name(node, 0); + init.parent_names = &parent_name; + init.num_parents = 1; - clk = clk_register_fixed_rate(NULL, "dbg_base_clk", NULL, CLK_IS_ROOT, SOCFPGA_MPU_CLK/2); - clk_register_clkdev(clk, "dbg_base_clk", NULL); + socfpga_clk->hw.init = &init; - clk = clk_register_fixed_rate(NULL, "main_qspi_clk", NULL, CLK_IS_ROOT, SOCFPGA_MAIN_QSPI_CLK); - clk_register_clkdev(clk, "main_qspi_clk", NULL); + clk = clk_register(NULL, &socfpga_clk->hw); + if (WARN_ON(IS_ERR(clk))) { + kfree(socfpga_clk); + return NULL; + } + rc = of_clk_add_provider(node, of_clk_src_simple_get, clk); + return clk; +} + +static void __init socfpga_pll_init(struct device_node *node) +{ + socfpga_clk_init(node, &clk_pll_ops); +} +CLK_OF_DECLARE(socfpga_pll, "altr,socfpga-pll-clock", socfpga_pll_init); + +static void __init socfpga_periph_init(struct device_node *node) +{ + socfpga_clk_init(node, &periclk_ops); +} +CLK_OF_DECLARE(socfpga_periph, "altr,socfpga-perip-clk", socfpga_periph_init); - clk = clk_register_fixed_rate(NULL, "main_nand_sdmmc_clk", NULL, CLK_IS_ROOT, SOCFPGA_MAIN_NAND_SDMMC_CLK); - clk_register_clkdev(clk, "main_nand_sdmmc_clk", NULL); +void __init socfpga_init_clocks(void) +{ + struct clk *clk; + int ret; - clk = clk_register_fixed_rate(NULL, "s2f_usr_clk", NULL, CLK_IS_ROOT, SOCFPGA_S2F_USR_CLK); - clk_register_clkdev(clk, "s2f_usr_clk", NULL); + clk = clk_register_fixed_factor(NULL, "smp_twd", "mpuclk", 0, 1, 4); + ret = clk_register_clkdev(clk, NULL, "smp_twd"); + if (ret) + pr_err("smp_twd alias not registered\n"); }