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Mon, 9 May 2022 05:44:34 +1000 (AEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=gmx.net; s=badeba3b8450; t=1652039035; bh=ARdVvvj+QR6zj7jH7tmlSixKEYcbCohZuth1Zlpb6F4=; h=X-UI-Sender-Class:From:To:Cc:Subject:Date:In-Reply-To:References; b=Dpfznk9P5+Yq1uW37Fv+kXuztyzVDIJqiZ1RTH0o+osGfBHJO90neIqP/+FOyxJtc uwqj3Qlsc2B2Gffe4g+gZntbf2dT4xv+/r9oxkFdbLFnZ615SzAS9WECWigsgPNFrK Hty2UuYQUUGltmw/PqHEOrLDQsRRmeVFHIUS3wws= X-UI-Sender-Class: 01bb95c1-4bf8-414a-932a-4f6e2808ef9c Received: from longitude ([37.201.215.103]) by mail.gmx.net (mrgmx005 [212.227.17.190]) with ESMTPSA (Nemesis) id 1N6KUd-1nqTVy18WX-016eKc; Sun, 08 May 2022 21:43:55 +0200 From: =?utf-8?q?Jonathan_Neusch=C3=A4fer?= To: linux-clk@vger.kernel.org, openbmc@lists.ozlabs.org Subject: [PATCH v3 6/7] clk: wpcm450: Add Nuvoton WPCM450 clock/reset controller driver Date: Sun, 8 May 2022 21:43:31 +0200 Message-Id: <20220508194333.2170161-7-j.neuschaefer@gmx.net> X-Mailer: git-send-email 2.35.1 In-Reply-To: <20220508194333.2170161-1-j.neuschaefer@gmx.net> References: <20220508194333.2170161-1-j.neuschaefer@gmx.net> MIME-Version: 1.0 X-Provags-ID: V03:K1:KrpzxJaSjCYOmWH1WrKsORKB3XhG/BxLuk+BPqLi4ogcSYKtqLf OWP9cG9FxjGoYQ9KxPIPzhQkWVg0cd7t9Jo2j6f46VPCExNnJDiTfoT9WI0f77BQhtp0HxG /nkghhKP7ya9gw4jiOrYctS8YU10mhgpZo55fkTGyXIsFo95TrU1M52MAEOmX8lSKN8x5vK SAhv3vArrb/5JqeMe2cgA== X-Spam-Flag: NO X-UI-Out-Filterresults: notjunk:1;V03:K0:agU9m9EU81E=:b49ndZc+x+GHg9prjc6On9 VyHjkR9O4Bo51NIQPB48B/VmmBOhi+CyHHWDWVowcAfxMJtyPF0L1DWqKcUQDmXaykCYh0lvx v8PoWV/5/jUmn1yRVIznPby2RXC9JCvjcwo9vZq4cTZEbOKgM9km4PzRVzFTN9V57h0UiHyIX 0KjbOD9eCO+iwhEz8VRxz0vk28iEtd07U96LNlHrAbUaSzh2UQwxdIAuJU0T7jPNyq347erUn MQMESDHVfL3dgUZl8Wbd9Eg+71FqVaZPab7PB9f/xtXz/W3RhVtKsO2glPxHG3m/hz5YENz53 89Gacz0BqrpzrH1dwC5jVAgC5qybsNuU9l2xOc/GDCUo0L42S1YkmRCEAtqHWjtIORV9p3W+W +JDE7HyU4Dxbs3SsmgEbun6Z1iIDEnWt6/U7Tw9+0tA3kUjGHnVp8Vw5pkV1433NiRlfkoN7S mSuExaeiYsOx7U+7+8fnXqAgjpfPdD+4Zg69gHxKMx+ibJpSQMQDu8znq6CGaEL/xbCiVaKxG IuqCqOl22G6dQXDnnv8iD1yPFG5c6izB9RvJV64KpO6GQYC45YjshlCN+U/hOu7plv/nmTdkk 78ykgJfxT3bABT+wE7gNoRzqkgpHZnb/elB4odJeLljOz9k2hHpvX715TpNBDo3RrOiYJ8c4H TxZzoZFNND9CrHSbvo2uyYuZiVtFmagly0VZgCF6+e00g4RJTIOVELDf20mmBRXpR/SGP4n4B QsD8HgFPzogCBn9ZdfRRxWErMg6U5XycidieCpRYuzDmlbBHmPdnGvH2p7B5G2pqJrqvbBH28 ud6ltgGXtSJVFR2A0uCBsDrWqgWOgUlBjXc8DXAoavUusyxJ490+SjWCaqEXYA1iPTkNnLXM3 yufm2jvSINukOJMhs0flAw1bcEJGhqUdZ4cwI0SATbi7Mdw4GVV3Ozucq5vwB23r8rYrpkFpi HIxI2Q1uNleK111zoBsWTuMKvrR9ZULQ1x9Mne37/bLQ3LSSMMJaFToe9YNgurVLuCagL37UZ 2gubdWdltOppIJSN6RZ2/4Fszlr2QnRylesnhwJKxhMdjazcT5KkJD7PVarQ6d5RvJufozvzg Epu0x12hbKWLgs= X-BeenThere: openbmc@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Development list for OpenBMC List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: devicetree@vger.kernel.org, Wim Van Sebroeck , linux-watchdog@vger.kernel.org, Stephen Boyd , Patrick Venture , Michael Turquette , Daniel Lezcano , linux-kernel@vger.kernel.org, =?utf-8?q?Jonathan_Neusch=C3=A4fer?= , Avi Fishman , Rob Herring , Benjamin Fair , Philipp Zabel , Krzysztof Kozlowski , Tali Perry , Thomas Gleixner , Guenter Roeck , Tomer Maimon Errors-To: openbmc-bounces+incoming=patchwork.ozlabs.org@lists.ozlabs.org Sender: "openbmc" This driver implements the following features w.r.t. the clock and reset controller in the WPCM450 SoC: - It calculates the rates for all clocks managed by the clock controller - It leaves the clock tree mostly unchanged, except that it enables/ disables clock gates based on usage. - It exposes the reset lines managed by the controller using the Generic Reset Controller subsystem NOTE: If the driver and the corresponding devicetree node are present, the driver will disable "unused" clocks. This is problem until the clock relations are properly declared in the devicetree (in a later patch). Until then, the clk_ignore_unused kernel parameter can be used as a workaround. Signed-off-by: Jonathan Neuschäfer --- v3: - Change reference clock name from "refclk" to "ref" - Remove unused variable in return path of wpcm450_clk_register_pll - Remove unused divisor tables v2: - https://lore.kernel.org/lkml/20220429172030.398011-7-j.neuschaefer@gmx.net/ - no changes --- drivers/clk/Makefile | 1 + drivers/clk/clk-wpcm450.c | 363 ++++++++++++++++++++++++++++++++++++++ drivers/reset/Kconfig | 2 +- 3 files changed, 365 insertions(+), 1 deletion(-) create mode 100644 drivers/clk/clk-wpcm450.c -- 2.35.1 diff --git a/drivers/clk/Makefile b/drivers/clk/Makefile index 2bd5ffd595bf3..07edb0f4ba8ba 100644 --- a/drivers/clk/Makefile +++ b/drivers/clk/Makefile @@ -73,6 +73,7 @@ obj-$(CONFIG_ARCH_VT8500) += clk-vt8500.o obj-$(CONFIG_COMMON_CLK_RS9_PCIE) += clk-renesas-pcie.o obj-$(CONFIG_COMMON_CLK_VC5) += clk-versaclock5.o obj-$(CONFIG_COMMON_CLK_WM831X) += clk-wm831x.o +obj-$(CONFIG_ARCH_WPCM450) += clk-wpcm450.o obj-$(CONFIG_COMMON_CLK_XGENE) += clk-xgene.o # please keep this section sorted lexicographically by directory path name diff --git a/drivers/clk/clk-wpcm450.c b/drivers/clk/clk-wpcm450.c new file mode 100644 index 0000000000000..09f40d6f9c896 --- /dev/null +++ b/drivers/clk/clk-wpcm450.c @@ -0,0 +1,363 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Nuvoton WPCM450 clock and reset controller driver. + * + * Copyright (C) 2022 Jonathan Neuschäfer + */ + +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include + +struct wpcm450_clk_pll { + struct clk_hw hw; + void __iomem *pllcon; + u8 flags; +}; + +#define to_wpcm450_clk_pll(_hw) container_of(_hw, struct wpcm450_clk_pll, hw) + +#define PLLCON_FBDV GENMASK(24, 16) +#define PLLCON_PRST BIT(13) +#define PLLCON_PWDEN BIT(12) +#define PLLCON_OTDV GENMASK(10, 8) +#define PLLCON_INDV GENMASK(5, 0) + +static unsigned long wpcm450_clk_pll_recalc_rate(struct clk_hw *hw, + unsigned long parent_rate) +{ + struct wpcm450_clk_pll *pll = to_wpcm450_clk_pll(hw); + unsigned long fbdv, indv, otdv; + u64 rate; + u32 pllcon; + + if (parent_rate == 0) { + pr_err("%s: parent rate is zero", __func__); + return 0; + } + + pllcon = readl_relaxed(pll->pllcon); + + indv = FIELD_GET(PLLCON_INDV, pllcon) + 1; + fbdv = FIELD_GET(PLLCON_FBDV, pllcon) + 1; + otdv = FIELD_GET(PLLCON_OTDV, pllcon) + 1; + + rate = (u64)parent_rate * fbdv; + do_div(rate, indv * otdv); + + return rate; +} + +static int wpcm450_clk_pll_is_enabled(struct clk_hw *hw) +{ + struct wpcm450_clk_pll *pll = to_wpcm450_clk_pll(hw); + u32 pllcon; + + pllcon = readl_relaxed(pll->pllcon); + + return !(pllcon & PLLCON_PRST); +} + +static void wpcm450_clk_pll_disable(struct clk_hw *hw) +{ + struct wpcm450_clk_pll *pll = to_wpcm450_clk_pll(hw); + u32 pllcon; + + pllcon = readl_relaxed(pll->pllcon); + pllcon |= PLLCON_PRST | PLLCON_PWDEN; + writel(pllcon, pll->pllcon); +} + +static const struct clk_ops wpcm450_clk_pll_ops = { + .recalc_rate = wpcm450_clk_pll_recalc_rate, + .is_enabled = wpcm450_clk_pll_is_enabled, + .disable = wpcm450_clk_pll_disable +}; + +static struct clk_hw * +wpcm450_clk_register_pll(void __iomem *pllcon, const char *name, + const char *parent_name, unsigned long flags) +{ + struct wpcm450_clk_pll *pll; + struct clk_init_data init; + int ret; + + pll = kzalloc(sizeof(*pll), GFP_KERNEL); + if (!pll) + return ERR_PTR(-ENOMEM); + + init.name = name; + init.ops = &wpcm450_clk_pll_ops; + init.parent_names = &parent_name; + init.num_parents = 1; + init.flags = flags; + + pll->pllcon = pllcon; + pll->hw.init = &init; + + ret = clk_hw_register(NULL, &pll->hw); + if (ret) { + kfree(pll); + return ERR_PTR(ret); + } + + return &pll->hw; +} + +#define REG_CLKEN 0x00 +#define REG_CLKSEL 0x04 +#define REG_CLKDIV 0x08 +#define REG_PLLCON0 0x0c +#define REG_PLLCON1 0x10 +#define REG_PMCON 0x14 +#define REG_IRQWAKECON 0x18 +#define REG_IRQWAKEFLAG 0x1c +#define REG_IPSRST 0x20 + +struct wpcm450_pll_data { + const char *name; + const char *parent_name; + unsigned int reg; + unsigned long flags; +}; + +static const struct wpcm450_pll_data pll_data[] = { + { "pll0", "ref", REG_PLLCON0, 0 }, + { "pll1", "ref", REG_PLLCON1, 0 }, +}; + +struct wpcm450_clksel_data { + const char *name; + const char *const *parent_names; + unsigned int num_parents; + const u32 *table; + int shift; + int width; + int index; + unsigned long flags; +}; + +static const u32 parent_table[] = { 0, 1, 2 }; +static const char *const default_parents[] = { "pll0", "pll1", "ref" }; +static const char *const huart_parents[] = { "ref", "refdiv2" }; + +static const struct wpcm450_clksel_data clksel_data[] = { + { "cpusel", default_parents, ARRAY_SIZE(default_parents), + parent_table, 0, 2, -1, CLK_IS_CRITICAL }, + { "clkout", default_parents, ARRAY_SIZE(default_parents), + parent_table, 2, 2, -1, 0 }, + { "usbphy", default_parents, ARRAY_SIZE(default_parents), + parent_table, 6, 2, -1, 0 }, + { "uartsel", default_parents, ARRAY_SIZE(default_parents), + parent_table, 8, 2, WPCM450_CLK_USBPHY, 0 }, + { "huartsel", huart_parents, ARRAY_SIZE(huart_parents), + parent_table, 10, 1, -1, 0 }, +}; + +static const struct clk_div_table div_fixed2[] = { + { .val = 0, .div = 2 }, + { } +}; + +struct wpcm450_clkdiv_data { + const char *name; + const char *parent_name; + int div_flags; + const struct clk_div_table *table; + int shift; + int width; + unsigned long flags; +}; + +static struct wpcm450_clkdiv_data clkdiv_data_early[] = { + { "refdiv2", "ref", 0, div_fixed2, 0, 0 }, +}; + +static const struct wpcm450_clkdiv_data clkdiv_data[] = { + { "cpu", "cpusel", 0, div_fixed2, 0, 0, CLK_IS_CRITICAL }, + { "adcdiv", "ref", CLK_DIVIDER_POWER_OF_TWO, NULL, 28, 2, 0 }, + { "apb", "ahb", CLK_DIVIDER_POWER_OF_TWO, NULL, 26, 2, 0 }, + { "ahb", "cpu", CLK_DIVIDER_POWER_OF_TWO, NULL, 24, 2, 0 }, + { "uart", "uartsel", 0, NULL, 16, 4, 0 }, + { "ahb3", "ahb", CLK_DIVIDER_POWER_OF_TWO, NULL, 8, 2, 0 }, +}; + +struct wpcm450_clken_data { + const char *name; + const char *parent_name; + int bitnum; + unsigned long flags; +}; + +static const struct wpcm450_clken_data clken_data[] = { + { "fiu", "ahb3", WPCM450_CLK_FIU, 0 }, + { "xbus", "ahb3", WPCM450_CLK_XBUS, 0 }, + { "kcs", "apb", WPCM450_CLK_KCS, 0 }, + { "shm", "ahb3", WPCM450_CLK_SHM, 0 }, + { "usb1", "ahb", WPCM450_CLK_USB1, 0 }, + { "emc0", "ahb", WPCM450_CLK_EMC0, 0 }, + { "emc1", "ahb", WPCM450_CLK_EMC1, 0 }, + { "usb0", "ahb", WPCM450_CLK_USB0, 0 }, + { "peci", "apb", WPCM450_CLK_PECI, 0 }, + { "aes", "apb", WPCM450_CLK_AES, 0 }, + { "uart0", "uart", WPCM450_CLK_UART0, 0 }, + { "uart1", "uart", WPCM450_CLK_UART1, 0 }, + { "smb2", "apb", WPCM450_CLK_SMB2, 0 }, + { "smb3", "apb", WPCM450_CLK_SMB3, 0 }, + { "smb4", "apb", WPCM450_CLK_SMB4, 0 }, + { "smb5", "apb", WPCM450_CLK_SMB5, 0 }, + { "huart", "huartsel", WPCM450_CLK_HUART, 0 }, + { "pwm", "apb", WPCM450_CLK_PWM, 0 }, + { "timer0", "refdiv2", WPCM450_CLK_TIMER0, 0 }, + { "timer1", "refdiv2", WPCM450_CLK_TIMER1, 0 }, + { "timer2", "refdiv2", WPCM450_CLK_TIMER2, 0 }, + { "timer3", "refdiv2", WPCM450_CLK_TIMER3, 0 }, + { "timer4", "refdiv2", WPCM450_CLK_TIMER4, 0 }, + { "mft0", "apb", WPCM450_CLK_MFT0, 0 }, + { "mft1", "apb", WPCM450_CLK_MFT1, 0 }, + { "wdt", "refdiv2", WPCM450_CLK_WDT, 0 }, + { "adc", "adcdiv", WPCM450_CLK_ADC, 0 }, + { "sdio", "ahb", WPCM450_CLK_SDIO, 0 }, + { "sspi", "apb", WPCM450_CLK_SSPI, 0 }, + { "smb0", "apb", WPCM450_CLK_SMB0, 0 }, + { "smb1", "apb", WPCM450_CLK_SMB1, 0 }, +}; + +static DEFINE_SPINLOCK(wpcm450_clk_lock); + +static void __init wpcm450_clk_init(struct device_node *clk_np) +{ + struct clk_hw_onecell_data *clk_data; + static struct clk_hw **hws; + static struct clk_hw *hw; + void __iomem *clk_base; + int i, ret; + struct reset_controller_dev *rcdev; + + clk_base = of_iomap(clk_np, 0); + if (!clk_base) { + pr_err("%pOFP: failed to map registers\n", clk_np); + of_node_put(clk_np); + return; + } + of_node_put(clk_np); + + clk_data = kzalloc(struct_size(clk_data, hws, WPCM450_NUM_CLKS), GFP_KERNEL); + if (!clk_data) + goto err_unmap; + + clk_data->num = WPCM450_NUM_CLKS; + hws = clk_data->hws; + + for (i = 0; i < WPCM450_NUM_CLKS; i++) + hws[i] = ERR_PTR(-ENOENT); + + // PLLs + for (i = 0; i < ARRAY_SIZE(pll_data); i++) { + const struct wpcm450_pll_data *data = &pll_data[i]; + + hw = wpcm450_clk_register_pll(clk_base + data->reg, data->name, + data->parent_name, data->flags); + if (IS_ERR(hw)) { + pr_info("Failed to register PLL: %pe", hw); + goto err_free; + } + } + + // Early divisors (REF/2) + for (i = 0; i < ARRAY_SIZE(clkdiv_data_early); i++) { + const struct wpcm450_clkdiv_data *data = &clkdiv_data_early[i]; + + hw = clk_hw_register_divider_table(NULL, data->name, data->parent_name, + data->flags, clk_base + REG_CLKDIV, + data->shift, data->width, data->div_flags, + data->table, &wpcm450_clk_lock); + if (IS_ERR(hw)) { + pr_err("Failed to register div table: %pe\n", hw); + goto err_free; + } + } + + // Selects/muxes + for (i = 0; i < ARRAY_SIZE(clksel_data); i++) { + const struct wpcm450_clksel_data *data = &clksel_data[i]; + + hw = clk_hw_register_mux_table(NULL, data->name, data->parent_names, + data->num_parents, data->flags, + clk_base + REG_CLKSEL, data->shift, + BIT(data->width) - 1, 0, data->table, + &wpcm450_clk_lock); + if (IS_ERR(hw)) { + pr_err("Failed to register mux: %pe\n", hw); + goto err_free; + } + if (data->index >= 0) + clk_data->hws[data->index] = hw; + } + + // Divisors + for (i = 0; i < ARRAY_SIZE(clkdiv_data); i++) { + const struct wpcm450_clkdiv_data *data = &clkdiv_data[i]; + + hw = clk_hw_register_divider_table(NULL, data->name, data->parent_name, + data->flags, clk_base + REG_CLKDIV, + data->shift, data->width, data->div_flags, + data->table, &wpcm450_clk_lock); + if (IS_ERR(hw)) { + pr_err("Failed to register divider: %pe\n", hw); + goto err_free; + } + } + + // Enables/gates + for (i = 0; i < ARRAY_SIZE(clken_data); i++) { + const struct wpcm450_clken_data *data = &clken_data[i]; + + hw = clk_hw_register_gate(NULL, data->name, data->parent_name, data->flags, + clk_base + REG_CLKEN, data->bitnum, + data->flags, &wpcm450_clk_lock); + if (IS_ERR(hw)) { + pr_err("Failed to register gate: %pe\n", hw); + goto err_free; + } + clk_data->hws[data->bitnum] = hw; + } + + ret = of_clk_add_hw_provider(clk_np, of_clk_hw_onecell_get, clk_data); + if (ret) + pr_err("Failed to add DT provider: %d\n", ret); + + // Reset controller + rcdev = kzalloc(sizeof(*rcdev), GFP_KERNEL); + if (!rcdev) + goto err_free; + rcdev->owner = THIS_MODULE; + rcdev->nr_resets = WPCM450_NUM_RESETS; + rcdev->ops = &reset_simple_ops; + rcdev->of_node = clk_np; + ret = reset_controller_register(rcdev); + if (ret) + pr_err("Failed to register reset controller: %d\n", ret); + + of_node_put(clk_np); + return; + +err_free: + kfree(clk_data->hws); +err_unmap: + iounmap(clk_base); + of_node_put(clk_np); +} + +CLK_OF_DECLARE(wpcm450_clk_init, "nuvoton,wpcm450-clk", wpcm450_clk_init); diff --git a/drivers/reset/Kconfig b/drivers/reset/Kconfig index b496028b6bfaf..50a3c1403c335 100644 --- a/drivers/reset/Kconfig +++ b/drivers/reset/Kconfig @@ -201,7 +201,7 @@ config RESET_SCMI config RESET_SIMPLE bool "Simple Reset Controller Driver" if COMPILE_TEST - default ARCH_ASPEED || ARCH_BCM4908 || ARCH_BITMAIN || ARCH_REALTEK || ARCH_STM32 || (ARCH_INTEL_SOCFPGA && ARM64) || ARCH_SUNXI || ARC + default ARCH_ASPEED || ARCH_BCM4908 || ARCH_BITMAIN || ARCH_REALTEK || ARCH_STM32 || (ARCH_INTEL_SOCFPGA && ARM64) || ARCH_SUNXI || ARC || ARCH_NPCM help This enables a simple reset controller driver for reset lines that that can be asserted and deasserted by toggling bits in a contiguous,