From patchwork Thu Feb 1 17:54:10 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Lucas Stach X-Patchwork-Id: 10195755 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 3D399601A0 for ; Thu, 1 Feb 2018 17:54:21 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 18C0B28C29 for ; Thu, 1 Feb 2018 17:54:21 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 0D95F28C2E; Thu, 1 Feb 2018 17:54:21 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.9 required=2.0 tests=BAYES_00,RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id E0A4528C17 for ; Thu, 1 Feb 2018 17:54:18 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752597AbeBARyS (ORCPT ); Thu, 1 Feb 2018 12:54:18 -0500 Received: from metis.ext.pengutronix.de ([85.220.165.71]:59095 "EHLO metis.ext.pengutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751956AbeBARyS (ORCPT ); Thu, 1 Feb 2018 12:54:18 -0500 Received: from dude.hi.pengutronix.de ([2001:67c:670:100:1d::7] helo=dude.pengutronix.de.) by metis.ext.pengutronix.de with esmtp (Exim 4.89) (envelope-from ) id 1ehJ3t-0006dJ-9O; Thu, 01 Feb 2018 18:54:13 +0100 From: Lucas Stach To: Michael Turquette , Stephen Boyd Cc: Rob Herring , Shawn Guo , Fabio Estevam , linux-clk@vger.kernel.org, devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org, kernel@pengutronix.de, patchwork-lst@pengutronix.de, "A . s . Dong" , linux-imx@nxp.com Subject: [PATCH v2 2/4] clk: imx: add fractional PLL output clock Date: Thu, 1 Feb 2018 18:54:10 +0100 Message-Id: <20180201175412.9480-2-l.stach@pengutronix.de> X-Mailer: git-send-email 2.15.1 In-Reply-To: <20180201175412.9480-1-l.stach@pengutronix.de> References: <20180201175412.9480-1-l.stach@pengutronix.de> X-SA-Exim-Connect-IP: 2001:67c:670:100:1d::7 X-SA-Exim-Mail-From: l.stach@pengutronix.de X-SA-Exim-Scanned: No (on metis.ext.pengutronix.de); SAEximRunCond expanded to false X-PTX-Original-Recipient: linux-clk@vger.kernel.org Sender: linux-clk-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-clk@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP This is a new clock type introduced on i.MX8. Signed-off-by: Lucas Stach --- drivers/clk/imx/Makefile | 1 + drivers/clk/imx/clk-frac-pll.c | 229 +++++++++++++++++++++++++++++++++++++++++ drivers/clk/imx/clk.h | 3 + 3 files changed, 233 insertions(+) create mode 100644 drivers/clk/imx/clk-frac-pll.c diff --git a/drivers/clk/imx/Makefile b/drivers/clk/imx/Makefile index f91f2b2e11cd..9892ae63539c 100644 --- a/drivers/clk/imx/Makefile +++ b/drivers/clk/imx/Makefile @@ -6,6 +6,7 @@ obj-y += \ clk-cpu.o \ clk-fixup-div.o \ clk-fixup-mux.o \ + clk-frac-pll.o \ clk-gate-exclusive.o \ clk-gate2.o \ clk-pllv1.o \ diff --git a/drivers/clk/imx/clk-frac-pll.c b/drivers/clk/imx/clk-frac-pll.c new file mode 100644 index 000000000000..30736d53dfbe --- /dev/null +++ b/drivers/clk/imx/clk-frac-pll.c @@ -0,0 +1,229 @@ +/* + * Copyright 2017 NXP. + * + * The code contained herein is licensed under the GNU General Public + * License. You may obtain a copy of the GNU General Public License + * Version 2 or later at the following locations: + * + * http://www.opensource.org/licenses/gpl-license.html + * http://www.gnu.org/copyleft/gpl.html + */ + +#include +#include +#include +#include +#include + +#include "clk.h" + +#define PLL_CFG0 0x0 +#define PLL_CFG1 0x4 + +#define PLL_LOCK_STATUS (0x1 << 31) +#define PLL_CLKE 21 +#define PLL_PD 19 +#define PLL_BYPASS 14 +#define PLL_NEWDIV_VAL (1 << 12) +#define PLL_NEWDIV_ACK (1 << 11) +#define PLL_FRAC_DIV_MASK 0xffffff +#define PLL_INT_DIV_MASK 0x7f +#define PLL_FRAC_DENOM 0x1000000 + +struct clk_frac_pll { + struct clk_hw hw; + void __iomem *base; +}; + +#define to_clk_frac_pll(_hw) container_of(_hw, struct clk_frac_pll, hw) + +static int clk_wait_lock(struct clk_frac_pll *pll) +{ + unsigned long timeout = jiffies + msecs_to_jiffies(10); + + /* Wait for PLL to lock */ + do { + if (readl_relaxed(pll->base) & PLL_LOCK_STATUS) + break; + if (time_after(jiffies, timeout)) + break; + } while (1); + + return readl_relaxed(pll->base) & PLL_LOCK_STATUS ? 0 : -ETIMEDOUT; +} + +static int clk_wait_ack(struct clk_frac_pll *pll) +{ + unsigned long timeout = jiffies + msecs_to_jiffies(50); + + /* return directly if the pll is in powerdown or in bypass */ + if (readl_relaxed(pll->base) & ((1 << PLL_PD) | (1 << PLL_BYPASS))) + return 0; + + /* Wait for the pll's divfi and divff to be reloaded */ + do { + if (readl_relaxed(pll->base) & PLL_NEWDIV_ACK) + break; + if (time_after(jiffies, timeout)) + break; + } while (1); + + return readl_relaxed(pll->base) & PLL_NEWDIV_ACK ? 0 : ETIMEDOUT; +} + +static int clk_pll_prepare(struct clk_hw *hw) +{ + struct clk_frac_pll *pll = to_clk_frac_pll(hw); + u32 val; + + val = readl_relaxed(pll->base + PLL_CFG0); + val &= ~(1 << PLL_PD); + writel_relaxed(val, pll->base + PLL_CFG0); + + return clk_wait_lock(pll); +} + +static void clk_pll_unprepare(struct clk_hw *hw) +{ + struct clk_frac_pll *pll = to_clk_frac_pll(hw); + u32 val; + + val = readl_relaxed(pll->base + PLL_CFG0); + val |= (1 << PLL_PD); + writel_relaxed(val, pll->base + PLL_CFG0); +} + +static int clk_pll_is_prepared(struct clk_hw *hw) +{ + struct clk_frac_pll *pll = to_clk_frac_pll(hw); + u32 val; + + val = readl_relaxed(pll->base + PLL_CFG0); + return (val & (1 << PLL_PD)) ? 0 : 1; +} + +static unsigned long clk_pll_recalc_rate(struct clk_hw *hw, + unsigned long parent_rate) +{ + struct clk_frac_pll *pll = to_clk_frac_pll(hw); + u32 val, divff, divfi, divq; + u64 temp64; + + val = readl_relaxed(pll->base + PLL_CFG0); + divq = ((val & 0x1f) + 1) * 2; + val = readl_relaxed(pll->base + PLL_CFG1); + divff = (val >> 7) & PLL_FRAC_DIV_MASK; + divfi = (val & PLL_INT_DIV_MASK); + + temp64 = (u64)parent_rate * 8; + temp64 *= divff; + do_div(temp64, PLL_FRAC_DENOM); + temp64 /= divq; + + return parent_rate * 8 * (divfi + 1) / divq + (unsigned long)temp64; +} + +static long clk_pll_round_rate(struct clk_hw *hw, unsigned long rate, + unsigned long *prate) +{ + u32 divff, divfi; + u64 temp64; + unsigned long parent_rate = *prate; + + parent_rate *= 8; + rate *= 2; + divfi = rate / parent_rate; + temp64 = (u64)(rate - divfi * parent_rate); + temp64 *= PLL_FRAC_DENOM; + do_div(temp64, parent_rate); + divff = temp64; + + temp64 = (u64)parent_rate; + temp64 *= divff; + do_div(temp64, PLL_FRAC_DENOM); + + return (parent_rate * divfi + (unsigned long)temp64) / 2; +} + +/* + * To simplify the clock calculation, we can keep the 'PLL_OUTPUT_VAL' at zero + * (means the PLL output will be divided by 2). So the PLL output can use + * the below formula: + * pllout = parent_rate * 8 / 2 * DIVF_VAL; + * where DIVF_VAL = 1 + DIVFI + DIVFF / 2^24. + */ +static int clk_pll_set_rate(struct clk_hw *hw, unsigned long rate, + unsigned long parent_rate) +{ + struct clk_frac_pll *pll = to_clk_frac_pll(hw); + u32 val, divfi, divff; + u64 temp64; + int ret; + + parent_rate *= 8; + rate *= 2; + divfi = rate / parent_rate; + temp64 = (u64) (rate - divfi * parent_rate); + temp64 *= PLL_FRAC_DENOM; + do_div(temp64, parent_rate); + divff = temp64; + + val = readl_relaxed(pll->base + PLL_CFG1); + val &= ~((PLL_FRAC_DIV_MASK << 7) | (PLL_INT_DIV_MASK)); + val |= ((divff << 7) | (divfi - 1)); + writel_relaxed(val, pll->base + PLL_CFG1); + + val = readl_relaxed(pll->base + PLL_CFG0); + val &= ~0x1f; + writel_relaxed(val, pll->base + PLL_CFG0); + + /* Set the NEV_DIV_VAL to reload the DIVFI and DIVFF */ + val = readl_relaxed(pll->base + PLL_CFG0); + val |= PLL_NEWDIV_VAL; + writel_relaxed(val, pll->base + PLL_CFG0); + + ret = clk_wait_ack(pll); + + /* clear the NEV_DIV_VAL */ + val = readl_relaxed(pll->base + PLL_CFG0); + val &= ~PLL_NEWDIV_VAL; + writel_relaxed(val, pll->base + PLL_CFG0); + + return ret; +} + +static const struct clk_ops clk_frac_pll_ops = { + .prepare = clk_pll_prepare, + .unprepare = clk_pll_unprepare, + .is_prepared = clk_pll_is_prepared, + .recalc_rate = clk_pll_recalc_rate, + .round_rate = clk_pll_round_rate, + .set_rate = clk_pll_set_rate, +}; + +struct clk *imx_clk_frac_pll(const char *name, const char *parent_name, + void __iomem *base) +{ + struct clk_frac_pll *pll; + struct clk *clk; + struct clk_init_data init; + + pll = kzalloc(sizeof(*pll), GFP_KERNEL); + if (!pll) + return ERR_PTR(-ENOMEM); + + pll->base = base; + init.name = name; + init.ops = &clk_frac_pll_ops; + init.flags = 0; + init.parent_names = &parent_name; + init.num_parents = 1; + + pll->hw.init = &init; + + clk = clk_register(NULL, &pll->hw); + if (IS_ERR(clk)) + kfree(pll); + + return clk; +} diff --git a/drivers/clk/imx/clk.h b/drivers/clk/imx/clk.h index d69c4bbf3597..287610902ea8 100644 --- a/drivers/clk/imx/clk.h +++ b/drivers/clk/imx/clk.h @@ -27,6 +27,9 @@ struct clk *imx_clk_pllv1(enum imx_pllv1_type type, const char *name, struct clk *imx_clk_pllv2(const char *name, const char *parent, void __iomem *base); +struct clk *imx_clk_frac_pll(const char *name, const char *parent_name, + void __iomem *base); + enum imx_pllv3_type { IMX_PLLV3_GENERIC, IMX_PLLV3_SYS,