From patchwork Fri Jun 3 19:05:09 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Romain Perier X-Patchwork-Id: 12869381 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id F30CBC43334 for ; Fri, 3 Jun 2022 19:06:48 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-Id:Date:Subject:Cc:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=rHQQXSkclKbhrIWZ2aYIGowN/dk+SJplspxUjsNzVso=; b=H//ygxkL6K+Rro kD48OgwBbptFk5Wg8wmjjU0jQCMC0mQlQoPDbCm6hktjJTODZCXSdgZYh6NI5acVFS8gj9M8SF372 sDjLGja/KuBXOUTIzKSGJF8eCmsLGpVjXPMU5iYc9wFOJEXCiTufX3vhwLhvSOMCEhCgpMbaWA0Pg HvmBQBhOtOqckhlEj82FfnY6MtmLGyMya9gciabiS9gBQwuJ3ok/Zk3Bg3YkgRM80MidHkefemLNw 7ohscLBlZ8m6yCTXUY9XJ8oYij+6mRwWmRDXBXsRucfqjgMkymG0rh5Q2iNaIIithXwYDIPWJuaGO vmm5ET0LDeyaPRWL5IPw==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1nxCbz-008UGT-S4; Fri, 03 Jun 2022 19:05:31 +0000 Received: from mail-wm1-x32b.google.com ([2a00:1450:4864:20::32b]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1nxCbn-008UCl-Q7 for linux-arm-kernel@lists.infradead.org; Fri, 03 Jun 2022 19:05:21 +0000 Received: by mail-wm1-x32b.google.com with SMTP id r123-20020a1c2b81000000b0039c1439c33cso4775315wmr.5 for ; Fri, 03 Jun 2022 12:05:17 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=ZFgBCEzYxQp8nY3gkKaQ0TK09MZ5JmYinUun8AjxLFE=; b=OPcbPulnRQaB+iSpztfpaDy+G4cPmsh7+SrJGOH4R3qs342HOGR5MNpcLLtXLVNGw7 8p7p4SbSHgMzaZ9S2GYN606b8BMct+b8p6GZIb0rd+Vb0W0Xckdk2m2fE+ue3pLa/KC/ zhz3F/eJRFXRybYryewuDbbgbDDVki5yjRaeGw8sAlzB7x0SDuoczeCSp4MF3PAQsW+w 3gzBj91uaKWvHT5CDC2cBPWgSIu6Hpo2oOY5Vh074Er/LaSrtOIPv4NkJgsHP7oo08iF acfpCrVDR9XmTtWsYZxO1KnKctbDveyWSKiUY4lx1jWlw8d3uP5w4vTwloyfcFfpbbpr Uz2A== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=ZFgBCEzYxQp8nY3gkKaQ0TK09MZ5JmYinUun8AjxLFE=; b=HNB7M2QxilpmUZXUkuobDu38AGk+FeA+e9iL7yxfrSNbSLB+21YGnAh9nrZ/ptZPzD y46JbYXK92aZswRsqaNl9dyC37HUD9OLrswp9ZxPb78fCiB5IAtQzkZgGPLfcbhbvtCa 3kGjlmQhf+FRp53dm1v6lsys1bgYg46P7IeBQuCLY6wNLfudLnbjC2gTn1B0a8acpuiu T8oWHaUFJr/+l8DOOlEUp40q9GgH1AK+d7+dKp9jIuo4xkPP9WDeYuCxFPlXZRIjdEZ/ Jc2x9uAPp+KVV4L8Fv0V6P2grEPD+jidd6ZPAcHGGqTwHXy2H0lnjlBQ8izZjTU7YCAB AiOg== X-Gm-Message-State: AOAM530C6BhesbdA1yb+VmPaNKWkcb0kvG5Ahnmh1iJryINK0rlWR6o4 F0ZqTk2Ti508G1plSURjmYI= X-Google-Smtp-Source: ABdhPJyF07BmHD4NSsYTBTnEZd6U8tMOFWKWYLvR8hVtDmbGqm0nkGji27EZArDy8UBlo34J2gYOhw== X-Received: by 2002:a05:600c:2e15:b0:39c:10cd:50d0 with SMTP id o21-20020a05600c2e1500b0039c10cd50d0mr24210096wmf.170.1654283116487; Fri, 03 Jun 2022 12:05:16 -0700 (PDT) Received: from debby ([2a01:e0a:a6d:a8d0:7ff4:8f61:5574:9f95]) by smtp.gmail.com with ESMTPSA id d10-20020a05600c34ca00b003942a244f33sm3553802wmq.12.2022.06.03.12.05.15 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 03 Jun 2022 12:05:15 -0700 (PDT) From: Romain Perier To: Michael Turquette , Stephen Boyd , linux-clk@vger.kernel.org, Daniel Palmer , Romain Perier Cc: linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, Willy Tarreau Subject: [PATCH RESEND v5 1/1] clk: mstar: msc313 cpupll clk driver Date: Fri, 3 Jun 2022 21:05:09 +0200 Message-Id: <20220603190509.45986-2-romain.perier@gmail.com> X-Mailer: git-send-email 2.35.1 In-Reply-To: <20220603190509.45986-1-romain.perier@gmail.com> References: <20220603190509.45986-1-romain.perier@gmail.com> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20220603_120519_897048_085E1525 X-CRM114-Status: GOOD ( 32.36 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org From: Daniel Palmer Add a driver for the CPU pll/ARM pll/MIPS pll that is present in MStar SoCs. Currently there is no documentation for this block so it's possible this driver isn't entirely correct. Only tested on the version of this IP in the MStar/SigmaStar ARMv7 SoCs. Co-authored-by: Willy Tarreau Signed-off-by: Daniel Palmer --- drivers/clk/mstar/Kconfig | 8 + drivers/clk/mstar/Makefile | 2 +- drivers/clk/mstar/clk-msc313-cpupll.c | 221 ++++++++++++++++++++++++++ 3 files changed, 230 insertions(+), 1 deletion(-) create mode 100644 drivers/clk/mstar/clk-msc313-cpupll.c diff --git a/drivers/clk/mstar/Kconfig b/drivers/clk/mstar/Kconfig index de37e1bce2d2..146eeb637318 100644 --- a/drivers/clk/mstar/Kconfig +++ b/drivers/clk/mstar/Kconfig @@ -1,4 +1,11 @@ # SPDX-License-Identifier: GPL-2.0-only +config MSTAR_MSC313_CPUPLL + bool "MStar CPUPLL driver" + depends on ARCH_MSTARV7 || COMPILE_TEST + default ARCH_MSTARV7 + help + Support for the CPU PLL present on MStar/Sigmastar SoCs. + config MSTAR_MSC313_MPLL bool "MStar MPLL driver" depends on ARCH_MSTARV7 || COMPILE_TEST @@ -7,3 +14,4 @@ config MSTAR_MSC313_MPLL help Support for the MPLL PLL and dividers block present on MStar/Sigmastar SoCs. + diff --git a/drivers/clk/mstar/Makefile b/drivers/clk/mstar/Makefile index f8dcd25ede1d..21296a04e65a 100644 --- a/drivers/clk/mstar/Makefile +++ b/drivers/clk/mstar/Makefile @@ -2,5 +2,5 @@ # # Makefile for mstar specific clk # - +obj-$(CONFIG_MSTAR_MSC313_CPUPLL) += clk-msc313-cpupll.o obj-$(CONFIG_MSTAR_MSC313_MPLL) += clk-msc313-mpll.o diff --git a/drivers/clk/mstar/clk-msc313-cpupll.c b/drivers/clk/mstar/clk-msc313-cpupll.c new file mode 100644 index 000000000000..c57b509e8c20 --- /dev/null +++ b/drivers/clk/mstar/clk-msc313-cpupll.c @@ -0,0 +1,221 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (C) 2019 Daniel Palmer + */ + +#include +#include +#include + +/* + * This IP is not documented outside of the messy vendor driver. + * Below is what we think the registers look like based on looking at + * the vendor code and poking at the hardware: + * + * 0x140 -- LPF low. Seems to store one half of the clock transition + * 0x144 / + * 0x148 -- LPF high. Seems to store one half of the clock transition + * 0x14c / + * 0x150 -- vendor code says "toggle lpf enable" + * 0x154 -- mu? + * 0x15c -- lpf_update_count? + * 0x160 -- vendor code says "switch to LPF". Clock source config? Register bank? + * 0x164 -- vendor code says "from low to high" which seems to mean transition from LPF low to + * LPF high. + * 0x174 -- Seems to be the PLL lock status bit + * 0x180 -- Seems to be the current frequency, this might need to be populated by software? + * 0x184 / The vendor driver uses these to set the initial value of LPF low + * + * Frequency seems to be calculated like this: + * (parent clock (432mhz) / register_magic_value) * 16 * 524288 + * Only the lower 24 bits of the resulting value will be used. In addition, the + * PLL doesn't seem to be able to lock on frequencies lower than 220 MHz, as + * divisor 0xfb586f (220 MHz) works but 0xfb7fff locks up. + * + * Vendor values: + * frequency - register value + * + * 400000000 - 0x0067AE14 + * 600000000 - 0x00451EB8, + * 800000000 - 0x0033D70A, + * 1000000000 - 0x002978d4, + */ + +#define REG_LPF_LOW_L 0x140 +#define REG_LPF_LOW_H 0x144 +#define REG_LPF_HIGH_BOTTOM 0x148 +#define REG_LPF_HIGH_TOP 0x14c +#define REG_LPF_TOGGLE 0x150 +#define REG_LPF_MYSTERYTWO 0x154 +#define REG_LPF_UPDATE_COUNT 0x15c +#define REG_LPF_MYSTERYONE 0x160 +#define REG_LPF_TRANSITIONCTRL 0x164 +#define REG_LPF_LOCK 0x174 +#define REG_CURRENT 0x180 + +#define LPF_LOCK_TIMEOUT 100000000 + +#define MULTIPLIER_1 16 +#define MULTIPLIER_2 524288 +#define MULTIPLIER (MULTIPLIER_1 * MULTIPLIER_2) + +struct msc313_cpupll { + void __iomem *base; + struct clk_hw clk_hw; +}; + +#define to_cpupll(_hw) container_of(_hw, struct msc313_cpupll, clk_hw) + +static u32 msc313_cpupll_reg_read32(struct msc313_cpupll *cpupll, unsigned int reg) +{ + u32 value; + + value = ioread16(cpupll->base + reg + 4) << 16; + value |= ioread16(cpupll->base + reg); + + return value; +} + +static void msc313_cpupll_reg_write32(struct msc313_cpupll *cpupll, unsigned int reg, u32 value) +{ + u16 l = value & 0xffff, h = (value >> 16) & 0xffff; + + iowrite16(l, cpupll->base + reg); + iowrite16(h, cpupll->base + reg + 4); +} + +static void msc313_cpupll_setfreq(struct msc313_cpupll *cpupll, u32 regvalue) +{ + ktime_t timeout; + + msc313_cpupll_reg_write32(cpupll, REG_LPF_HIGH_BOTTOM, regvalue); + + iowrite16(0x1, cpupll->base + REG_LPF_MYSTERYONE); + iowrite16(0x6, cpupll->base + REG_LPF_MYSTERYTWO); + iowrite16(0x8, cpupll->base + REG_LPF_UPDATE_COUNT); + iowrite16(BIT(12), cpupll->base + REG_LPF_TRANSITIONCTRL); + + iowrite16(0, cpupll->base + REG_LPF_TOGGLE); + iowrite16(1, cpupll->base + REG_LPF_TOGGLE); + + timeout = ktime_add_ns(ktime_get(), LPF_LOCK_TIMEOUT); + while (!(ioread16(cpupll->base + REG_LPF_LOCK))) { + if (ktime_after(ktime_get(), timeout)) { + pr_err("timeout waiting for LPF_LOCK\n"); + return; + } + cpu_relax(); + } + + iowrite16(0, cpupll->base + REG_LPF_TOGGLE); + + msc313_cpupll_reg_write32(cpupll, REG_LPF_LOW_L, regvalue); +} + +static unsigned long msc313_cpupll_frequencyforreg(u32 reg, unsigned long parent_rate) +{ + unsigned long long prescaled = ((unsigned long long)parent_rate) * MULTIPLIER; + + if (prescaled == 0 || reg == 0) + return 0; + return DIV_ROUND_DOWN_ULL(prescaled, reg); +} + +static u32 msc313_cpupll_regforfrequecy(unsigned long rate, unsigned long parent_rate) +{ + unsigned long long prescaled = ((unsigned long long)parent_rate) * MULTIPLIER; + + if (prescaled == 0 || rate == 0) + return 0; + return DIV_ROUND_UP_ULL(prescaled, rate); +} + +static unsigned long msc313_cpupll_recalc_rate(struct clk_hw *hw, unsigned long parent_rate) +{ + struct msc313_cpupll *cpupll = to_cpupll(hw); + + return msc313_cpupll_frequencyforreg(msc313_cpupll_reg_read32(cpupll, REG_LPF_LOW_L), + parent_rate); +} + +static long msc313_cpupll_round_rate(struct clk_hw *hw, unsigned long rate, + unsigned long *parent_rate) +{ + u32 reg = msc313_cpupll_regforfrequecy(rate, *parent_rate); + long rounded = msc313_cpupll_frequencyforreg(reg, *parent_rate); + + /* + * This is my poor attempt at making sure the resulting + * rate doesn't overshoot the requested rate. + */ + for (; rounded >= rate && reg > 0; reg--) + rounded = msc313_cpupll_frequencyforreg(reg, *parent_rate); + + return rounded; +} + +static int msc313_cpupll_set_rate(struct clk_hw *hw, unsigned long rate, unsigned long parent_rate) +{ + struct msc313_cpupll *cpupll = to_cpupll(hw); + u32 reg = msc313_cpupll_regforfrequecy(rate, parent_rate); + + msc313_cpupll_setfreq(cpupll, reg); + + return 0; +} + +static const struct clk_ops msc313_cpupll_ops = { + .recalc_rate = msc313_cpupll_recalc_rate, + .round_rate = msc313_cpupll_round_rate, + .set_rate = msc313_cpupll_set_rate, +}; + +static const struct of_device_id msc313_cpupll_of_match[] = { + { .compatible = "mstar,msc313-cpupll" }, + {} +}; + +static const struct clk_parent_data cpupll_parent = { + .index = 0, +}; + +static int msc313_cpupll_probe(struct platform_device *pdev) +{ + struct clk_init_data clk_init = {}; + struct device *dev = &pdev->dev; + struct msc313_cpupll *cpupll; + int ret; + + cpupll = devm_kzalloc(&pdev->dev, sizeof(*cpupll), GFP_KERNEL); + if (!cpupll) + return -ENOMEM; + + cpupll->base = devm_platform_ioremap_resource(pdev, 0); + if (IS_ERR(cpupll->base)) + return PTR_ERR(cpupll->base); + + /* LPF might not contain the current frequency so fix that up */ + msc313_cpupll_reg_write32(cpupll, REG_LPF_LOW_L, + msc313_cpupll_reg_read32(cpupll, REG_CURRENT)); + + clk_init.name = dev_name(dev); + clk_init.ops = &msc313_cpupll_ops; + clk_init.parent_data = &cpupll_parent; + clk_init.num_parents = 1; + cpupll->clk_hw.init = &clk_init; + + ret = devm_clk_hw_register(dev, &cpupll->clk_hw); + if (ret) + return ret; + + return of_clk_add_hw_provider(pdev->dev.of_node, of_clk_hw_simple_get, &cpupll->clk_hw); +} + +static struct platform_driver msc313_cpupll_driver = { + .driver = { + .name = "mstar-msc313-cpupll", + .of_match_table = msc313_cpupll_of_match, + }, + .probe = msc313_cpupll_probe, +}; +builtin_platform_driver(msc313_cpupll_driver);