Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1946314Ab2JYQMh (ORCPT ); Thu, 25 Oct 2012 12:12:37 -0400 Received: from bear.ext.ti.com ([192.94.94.41]:48065 "EHLO bear.ext.ti.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1946198Ab2JYQM3 (ORCPT ); Thu, 25 Oct 2012 12:12:29 -0400 From: Murali Karicheri To: , , , , , , , , , , , , , CC: , Murali Karicheri Subject: [PATCH v3 01/11] clk: davinci - add main PLL clock driver Date: Thu, 25 Oct 2012 12:11:47 -0400 Message-ID: <1351181518-11882-2-git-send-email-m-karicheri2@ti.com> X-Mailer: git-send-email 1.7.9.5 In-Reply-To: <1351181518-11882-1-git-send-email-m-karicheri2@ti.com> References: <1351181518-11882-1-git-send-email-m-karicheri2@ti.com> MIME-Version: 1.0 Content-Type: text/plain Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 6861 Lines: 241 This is the driver for the main PLL clock hardware found on DM SoCs. This driver borrowed code from arch/arm/mach-davinci/clock.c and implemented the driver as per common clock provider API. The main PLL hardware typically has a multiplier, a pre-divider and a post-divider. Some of the SoCs has the divider fixed meaning they can not be configured through a register. HAS_PREDIV and HAS_POSTDIV flags are used to tell the driver if a hardware has these dividers present or not. Driver is configured through the struct clk_pll_data that has the SoC specific clock data. Signed-off-by: Murali Karicheri --- drivers/clk/davinci/clk-pll.c | 146 +++++++++++++++++++++++++++++++++++++++++ drivers/clk/davinci/clk-pll.h | 57 ++++++++++++++++ 2 files changed, 203 insertions(+) create mode 100644 drivers/clk/davinci/clk-pll.c create mode 100644 drivers/clk/davinci/clk-pll.h diff --git a/drivers/clk/davinci/clk-pll.c b/drivers/clk/davinci/clk-pll.c new file mode 100644 index 0000000..337e9af --- /dev/null +++ b/drivers/clk/davinci/clk-pll.c @@ -0,0 +1,146 @@ +/* + * DaVinci main pll clk driver + * + * Copyright (C) 2006-2012 Texas Instruments. + * Copyright (C) 2008-2009 Deep Root Systems, LLC + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * DaVinci PLL clk driver implementation + * + * TODO - Add set_parent_rate() + */ +#include +#include +#include +#include +#include +#include + +#include "clk-pll.h" + +#define PLLDIV_EN BIT(15) + +/** + * struct clk_pll - DaVinci main pll clock + * @hw: clk_hw for the pll + * @pll_data: ptr to driver specific data + */ +struct clk_pll { + struct clk_hw hw; + struct clk_pll_data *pll_data; +}; + +#define to_clk_pll(_hw) container_of(_hw, struct clk_pll, hw) + +/** + * clk_pllclk_recalc() - function to calculate rate + * + * @hw: clk_hw for the pll + * @parent_rate: Parent clk rate + */ +static unsigned long clk_pllclk_recalc(struct clk_hw *hw, + unsigned long parent_rate) +{ + struct clk_pll *pll = to_clk_pll(hw); + struct clk_pll_data *pll_data = pll->pll_data; + u32 mult = 1, prediv = 1, postdiv = 1; + unsigned long rate = parent_rate; + + mult = readl(pll_data->reg_pllm); + + /* + * if fixed_multiplier is non zero, multiply pllm value by this + * value. + */ + if (pll_data->fixed_multiplier) + mult = pll_data->fixed_multiplier * + (mult & pll_data->pllm_mask); + else + mult = (mult & pll_data->pllm_mask) + 1; + + if (pll_data->pll_flags & CLK_DAVINCI_PLL_HAS_PREDIV) { + /* + * prediv register is not present, take fixed_prediv value from + * pll_data for prediv + */ + if (pll_data->fixed_prediv) { + prediv = pll_data->fixed_prediv; + } else { + prediv = readl(pll_data->reg_prediv); + if (prediv & PLLDIV_EN) + prediv = (prediv & pll_data->prediv_mask) + 1; + else + prediv = 1; + } + } + + if (pll_data->pll_flags & CLK_DAVINCI_PLL_HAS_POSTDIV) { + postdiv = readl(pll_data->reg_postdiv); + if (postdiv & PLLDIV_EN) + postdiv = (postdiv & pll_data->postdiv_mask) + 1; + else + postdiv = 1; + } + + rate /= prediv; + rate *= mult; + rate /= postdiv; + + pr_debug("PLL%d: input = %lu MHz [ ", + pll_data->num, parent_rate / 1000000); + if (prediv > 1) + pr_debug("/ %d ", prediv); + if (mult > 1) + pr_debug("* %d ", mult); + if (postdiv > 1) + pr_debug("/ %d ", postdiv); + pr_debug("] --> %lu MHz output.\n", rate / 1000000); + + return rate; +} + +static const struct clk_ops clk_pll_ops = { + .recalc_rate = clk_pllclk_recalc, +}; + +/** + * clk_register_davinci_pll() - register function for DaVinci main pll clk + * + * @dev: device ptr + * @name: name of the clk + * @parent_name: name of the parent clk + * @pll_data: ptr to pll clk data + */ +struct clk *clk_register_davinci_pll(struct device *dev, const char *name, + const char *parent_name, + struct clk_pll_data *pll_data) +{ + struct clk_init_data init; + struct clk_pll *pll; + struct clk *clk; + + if (!pll_data) + return ERR_PTR(-ENODEV); + + pll = kzalloc(sizeof(*pll), GFP_KERNEL); + if (!pll) + return ERR_PTR(-ENOMEM); + + init.name = name; + init.ops = &clk_pll_ops; + init.flags = pll_data->flags; + init.parent_names = (parent_name ? &parent_name : NULL); + init.num_parents = (parent_name ? 1 : 0); + + pll->pll_data = pll_data; + pll->hw.init = &init; + + clk = clk_register(NULL, &pll->hw); + if (IS_ERR(clk)) + kfree(pll); + + return clk; +} diff --git a/drivers/clk/davinci/clk-pll.h b/drivers/clk/davinci/clk-pll.h new file mode 100644 index 0000000..c9e4826 --- /dev/null +++ b/drivers/clk/davinci/clk-pll.h @@ -0,0 +1,57 @@ +/* + * Header file for DaVinci main pll clk driver + * + * Copyright (C) 2006-2012 Texas Instruments. + * Copyright (C) 2008-2009 Deep Root Systems, LLC + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * DaVinci PLL clk driver implementation + * + * TODO - Add set_parent_rate() + */ + +#ifndef __CLK_DAVINCI_PLL_H +#define __CLK_DAVINCI_PLL_H + +/* PLL flags */ +#define CLK_DAVINCI_PLL_HAS_PREDIV BIT(0) +#define CLK_DAVINCI_PLL_HAS_POSTDIV BIT(1) + +/** + * struct clk_pll_data - configuration for DaVinci main PLL clk driver + * + * @reg_pllm: io mapped address of pllm register + * @reg_prediv: io mapped address of prediv register + * @reg_postdiv: io mapped address of postdiv register + * @pllm_mask: mask bits for pllm val + * @prediv_mask: mask bits for prediv val + * @postdiv_mask: mask bits for postdiv val + * @num: PLL number. Some SoCs have more than one main PLL + * 0 - PLL0 and 1 - PLL1 + * @flags - clk driver base flags + * @pll_flags - clk_pll driver flags + * @fixed_prediv - fixed value of prediv used instead of value from prediv reg + * @fixed_multiplier - pllm register value is multiplied by this factor on a + * a particular SoC. For other SoCs, this is set to zero. + */ +struct clk_pll_data { + void __iomem *reg_pllm; + void __iomem *reg_prediv; + void __iomem *reg_postdiv; + u32 pllm_mask; + u32 prediv_mask; + u32 postdiv_mask; + u32 num; + u32 flags; + u32 pll_flags; + u32 fixed_prediv; + u32 fixed_multiplier; +}; + +struct clk *clk_register_davinci_pll(struct device *dev, + const char *name, const char *parent_name, + struct clk_pll_data *pll_data); +#endif /* CLK_DAVINCI_PLL_H */ -- 1.7.9.5 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/