From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1162218AbcFGUqd (ORCPT ); Tue, 7 Jun 2016 16:46:33 -0400 Received: from down.free-electrons.com ([37.187.137.238]:52934 "EHLO mail.free-electrons.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1753046AbcFGUmL (ORCPT ); Tue, 7 Jun 2016 16:42:11 -0400 From: Maxime Ripard To: Mike Turquette , Stephen Boyd , Chen-Yu Tsai Cc: linux-clk@vger.kernel.org, Hans de Goede , Andre Przywara , Rob Herring , Vishnu Patekar , linux-arm-kernel@lists.infradead.org, Boris Brezillon , Jean-Francois Moine , linux-kernel@vger.kernel.org, devicetree@vger.kernel.org, Maxime Ripard Subject: [PATCH v2 03/15] clk: sunxi-ng: Add fractional lib Date: Tue, 7 Jun 2016 22:41:42 +0200 Message-Id: <20160607204154.31967-4-maxime.ripard@free-electrons.com> X-Mailer: git-send-email 2.8.3 In-Reply-To: <20160607204154.31967-1-maxime.ripard@free-electrons.com> References: <20160607204154.31967-1-maxime.ripard@free-electrons.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Some clocks can be switched to a mode called fractional that have two fixed output rate you can choose from. Add a small library to deal with those clocks. Signed-off-by: Maxime Ripard --- drivers/clk/sunxi-ng/Makefile | 2 + drivers/clk/sunxi-ng/ccu_frac.c | 110 ++++++++++++++++++++++++++++++++++++++++ drivers/clk/sunxi-ng/ccu_frac.h | 53 +++++++++++++++++++ 3 files changed, 165 insertions(+) create mode 100644 drivers/clk/sunxi-ng/ccu_frac.c create mode 100644 drivers/clk/sunxi-ng/ccu_frac.h diff --git a/drivers/clk/sunxi-ng/Makefile b/drivers/clk/sunxi-ng/Makefile index bd3461b0f38c..4585443b3771 100644 --- a/drivers/clk/sunxi-ng/Makefile +++ b/drivers/clk/sunxi-ng/Makefile @@ -1,2 +1,4 @@ obj-y += ccu_common.o obj-y += ccu_reset.o + +obj-y += ccu_frac.o diff --git a/drivers/clk/sunxi-ng/ccu_frac.c b/drivers/clk/sunxi-ng/ccu_frac.c new file mode 100644 index 000000000000..5c4b10cd15b5 --- /dev/null +++ b/drivers/clk/sunxi-ng/ccu_frac.c @@ -0,0 +1,110 @@ +/* + * Copyright (C) 2016 Maxime Ripard + * Maxime Ripard + * + * 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; either version 2 of + * the License, or (at your option) any later version. + */ + +#include +#include + +#include "ccu_frac.h" + +bool ccu_frac_helper_is_enabled(struct ccu_common *common, + struct _ccu_frac *cf) +{ + if (!(common->features & CCU_FEATURE_FRACTIONAL)) + return false; + + return !(readl(common->base + common->reg) & cf->enable); +} + +void ccu_frac_helper_enable(struct ccu_common *common, + struct _ccu_frac *cf) +{ + unsigned long flags; + u32 reg; + + if (!(common->features & CCU_FEATURE_FRACTIONAL)) + return; + + spin_lock_irqsave(common->lock, flags); + reg = readl(common->base + common->reg); + writel(reg & ~cf->enable, common->base + common->reg); + spin_unlock_irqrestore(common->lock, flags); +} + +void ccu_frac_helper_disable(struct ccu_common *common, + struct _ccu_frac *cf) +{ + unsigned long flags; + u32 reg; + + if (!(common->features & CCU_FEATURE_FRACTIONAL)) + return; + + spin_lock_irqsave(common->lock, flags); + reg = readl(common->base + common->reg); + writel(reg | cf->enable, common->base + common->reg); + spin_unlock_irqrestore(common->lock, flags); +} + +bool ccu_frac_helper_has_rate(struct ccu_common *common, + struct _ccu_frac *cf, + unsigned long rate) +{ + if (!(common->features & CCU_FEATURE_FRACTIONAL)) + return false; + + return (cf->rates[0] == rate) || (cf->rates[1] == rate); +} + +unsigned long ccu_frac_helper_read_rate(struct ccu_common *common, + struct _ccu_frac *cf) +{ + u32 reg; + + printk("%s: Read fractional\n", clk_hw_get_name(&common->hw)); + + if (!(common->features & CCU_FEATURE_FRACTIONAL)) + return 0; + + printk("%s: clock is fractional (rates %lu and %lu)\n", + clk_hw_get_name(&common->hw), cf->rates[0], cf->rates[1]); + + reg = readl(common->base + common->reg); + + printk("%s: clock reg is 0x%x (select is 0x%x)\n", + clk_hw_get_name(&common->hw), reg, cf->select); + + return (reg & cf->select) ? cf->rates[1] : cf->rates[0]; +} + +int ccu_frac_helper_set_rate(struct ccu_common *common, + struct _ccu_frac *cf, + unsigned long rate) +{ + unsigned long flags; + u32 reg, sel; + + if (!(common->features & CCU_FEATURE_FRACTIONAL)) + return -EINVAL; + + if (cf->rates[0] == rate) + sel = 0; + else if (cf->rates[1] == rate) + sel = cf->select; + else + return -EINVAL; + + spin_lock_irqsave(common->lock, flags); + reg = readl(common->base + common->reg); + reg &= ~cf->select; + writel(reg | sel, common->base + common->reg); + spin_unlock_irqrestore(common->lock, flags); + + return 0; +} diff --git a/drivers/clk/sunxi-ng/ccu_frac.h b/drivers/clk/sunxi-ng/ccu_frac.h new file mode 100644 index 000000000000..e4c670b1cdfe --- /dev/null +++ b/drivers/clk/sunxi-ng/ccu_frac.h @@ -0,0 +1,53 @@ +/* + * Copyright (c) 2016 Maxime Ripard. All rights reserved. + * + * This software is licensed under the terms of the GNU General Public + * License version 2, as published by the Free Software Foundation, and + * may be copied, distributed, and modified under those terms. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + */ + +#ifndef _CCU_FRAC_H_ +#define _CCU_FRAC_H_ + +#include + +#include "ccu_common.h" + +struct _ccu_frac { + u32 enable; + u32 select; + + unsigned long rates[2]; +}; + +#define _SUNXI_CCU_FRAC(_enable, _select, _rate1, _rate2) \ + { \ + .enable = _enable, \ + .select = _select, \ + .rates = { _rate1, _rate2 }, \ + } + +bool ccu_frac_helper_is_enabled(struct ccu_common *common, + struct _ccu_frac *cf); +void ccu_frac_helper_enable(struct ccu_common *common, + struct _ccu_frac *cf); +void ccu_frac_helper_disable(struct ccu_common *common, + struct _ccu_frac *cf); + +bool ccu_frac_helper_has_rate(struct ccu_common *common, + struct _ccu_frac *cf, + unsigned long rate); + +unsigned long ccu_frac_helper_read_rate(struct ccu_common *common, + struct _ccu_frac *cf); + +int ccu_frac_helper_set_rate(struct ccu_common *common, + struct _ccu_frac *cf, + unsigned long rate); + +#endif /* _CCU_FRAC_H_ */ -- 2.8.3