Add driver code for the SiFive FU540 PRCI IP block. This IP block handles reset and clock control for the SiFive FU540 device and implements SoC-level clock tree controls and dividers. Based on code written by Wesley Terpstra <wesley@xxxxxxxxxx>: https://github.com/riscv/riscv-linux/commit/999529edf517ed75b56659d456d221b2ee56bb60 Boot and PLL rate change were tested on a SiFive HiFive Unleashed board. Cc: Michael Turquette <mturquette@xxxxxxxxxxxx> Cc: Stephen Boyd <sboyd@xxxxxxxxxx> Cc: Albert Ou <aou@xxxxxxxxxxxxxxxxx> Cc: Wesley W. Terpstra <wesley@xxxxxxxxxx> Cc: Palmer Dabbelt <palmer@xxxxxxxxxx> Cc: Megan Wachs <megan@xxxxxxxxxx> Cc: linux-riscv@xxxxxxxxxxxxxxxxxxx Cc: linux-kernel@xxxxxxxxxxxxxxx Cc: linux-clk@xxxxxxxxxxxxxxx Signed-off-by: Paul Walmsley <paul.walmsley@xxxxxxxxxx> Signed-off-by: Paul Walmsley <paul@xxxxxxxxx> --- drivers/clk/Kconfig | 1 + drivers/clk/Makefile | 1 + drivers/clk/sifive/Kconfig | 18 + drivers/clk/sifive/Makefile | 1 + drivers/clk/sifive/fu540-prci.c | 634 ++++++++++++++++++++++++++ include/linux/clk/sifive-fu540-prci.h | 27 ++ 6 files changed, 682 insertions(+) create mode 100644 drivers/clk/sifive/Kconfig create mode 100644 drivers/clk/sifive/Makefile create mode 100644 drivers/clk/sifive/fu540-prci.c create mode 100644 include/linux/clk/sifive-fu540-prci.h diff --git a/drivers/clk/Kconfig b/drivers/clk/Kconfig index a34ccfcb54ac..0af5f6843a2f 100644 --- a/drivers/clk/Kconfig +++ b/drivers/clk/Kconfig @@ -295,6 +295,7 @@ source "drivers/clk/mvebu/Kconfig" source "drivers/clk/qcom/Kconfig" source "drivers/clk/renesas/Kconfig" source "drivers/clk/samsung/Kconfig" +source "drivers/clk/sifive/Kconfig" source "drivers/clk/sprd/Kconfig" source "drivers/clk/sunxi-ng/Kconfig" source "drivers/clk/tegra/Kconfig" diff --git a/drivers/clk/Makefile b/drivers/clk/Makefile index d59c11ddfc5e..8b07ebab37f8 100644 --- a/drivers/clk/Makefile +++ b/drivers/clk/Makefile @@ -91,6 +91,7 @@ obj-$(CONFIG_COMMON_CLK_QCOM) += qcom/ obj-y += renesas/ obj-$(CONFIG_ARCH_ROCKCHIP) += rockchip/ obj-$(CONFIG_COMMON_CLK_SAMSUNG) += samsung/ +obj-y += sifive/ obj-$(CONFIG_ARCH_SIRF) += sirf/ obj-$(CONFIG_ARCH_SOCFPGA) += socfpga/ obj-$(CONFIG_PLAT_SPEAR) += spear/ diff --git a/drivers/clk/sifive/Kconfig b/drivers/clk/sifive/Kconfig new file mode 100644 index 000000000000..8db4a3eb4782 --- /dev/null +++ b/drivers/clk/sifive/Kconfig @@ -0,0 +1,18 @@ +# SPDX-License-Identifier: GPL-2.0 + +menuconfig CLK_SIFIVE + bool "SiFive SoC driver support" + help + SoC drivers for SiFive Linux-capable SoCs. + +if CLK_SIFIVE + +config CLK_SIFIVE_FU540_PRCI + bool "PRCI driver for SiFive FU540 SoCs" + select CLK_ANALOGBITS_WRPLL_CLN28HPC + help + Supports the Power Reset Clock interface (PRCI) IP block found in + FU540 SoCs. If this kernel is meant to run on a SiFive FU540 SoC, + enable this driver. + +endif diff --git a/drivers/clk/sifive/Makefile b/drivers/clk/sifive/Makefile new file mode 100644 index 000000000000..74d58a4c0756 --- /dev/null +++ b/drivers/clk/sifive/Makefile @@ -0,0 +1 @@ +obj-$(CONFIG_CLK_SIFIVE_FU540_PRCI) += fu540-prci.o diff --git a/drivers/clk/sifive/fu540-prci.c b/drivers/clk/sifive/fu540-prci.c new file mode 100644 index 000000000000..870cb8333648 --- /dev/null +++ b/drivers/clk/sifive/fu540-prci.c @@ -0,0 +1,634 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (C) 2018 SiFive, Inc. + * Wesley Terpstra + * Paul Walmsley + * + * 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. + * + * 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. + * + * The FU540 PRCI implements clock and reset control for the SiFive + * FU540-C000 chip. This driver assumes that it has sole control + * over all PRCI resources. + * + * This driver is based on the PRCI driver written by Wesley Terpstra: + * https://github.com/riscv/riscv-linux/commit/999529edf517ed75b56659d456d221b2ee56bb60 + * + * References: + * - SiFive FU540-C000 manual v1p0, Chapter 7 "Clocking and Reset" + */ + +#include <linux/clkdev.h> +#include <linux/clk-provider.h> +#include <linux/clk.h> +#include <linux/clk/analogbits-wrpll-cln28hpc.h> +#include <linux/delay.h> +#include <linux/err.h> +#include <linux/log2.h> +#include <linux/of.h> +#include <linux/platform_device.h> +#include <linux/slab.h> +#include <linux/clk/sifive-fu540-prci.h> + +/* + * EXPECTED_CLK_PARENT_COUNT: how many parent clocks this driver expects: + * hfclk and rtcclk + */ +#define EXPECTED_CLK_PARENT_COUNT 2 + +/* + * Register offsets and bitmasks + */ + +/* COREPLLCFG0 */ +#define PRCI_COREPLLCFG0_OFFSET 0x4 +# define PRCI_COREPLLCFG0_DIVR_SHIFT 0 +# define PRCI_COREPLLCFG0_DIVR_MASK (0x3f << PRCI_COREPLLCFG0_DIVR_SHIFT) +# define PRCI_COREPLLCFG0_DIVF_SHIFT 6 +# define PRCI_COREPLLCFG0_DIVF_MASK (0x1ff << PRCI_COREPLLCFG0_DIVF_SHIFT) +# define PRCI_COREPLLCFG0_DIVQ_SHIFT 15 +# define PRCI_COREPLLCFG0_DIVQ_MASK (0x7 << PRCI_COREPLLCFG0_DIVQ_SHIFT) +# define PRCI_COREPLLCFG0_RANGE_SHIFT 18 +# define PRCI_COREPLLCFG0_RANGE_MASK (0x7 << PRCI_COREPLLCFG0_RANGE_SHIFT) +# define PRCI_COREPLLCFG0_BYPASS_SHIFT 24 +# define PRCI_COREPLLCFG0_BYPASS_MASK (0x1 << PRCI_COREPLLCFG0_BYPASS_SHIFT) +# define PRCI_COREPLLCFG0_FSE_SHIFT 25 +# define PRCI_COREPLLCFG0_FSE_MASK (0x1 << PRCI_COREPLLCFG0_FSE_SHIFT) +# define PRCI_COREPLLCFG0_LOCK_SHIFT 31 +# define PRCI_COREPLLCFG0_LOCK_MASK (0x1 << PRCI_COREPLLCFG0_LOCK_SHIFT) + +/* DDRPLLCFG0 */ +#define PRCI_DDRPLLCFG0_OFFSET 0xc +# define PRCI_DDRPLLCFG0_DIVR_SHIFT 0 +# define PRCI_DDRPLLCFG0_DIVR_MASK (0x3f << PRCI_DDRPLLCFG0_DIVR_SHIFT) +# define PRCI_DDRPLLCFG0_DIVF_SHIFT 6 +# define PRCI_DDRPLLCFG0_DIVF_MASK (0x1ff << PRCI_DDRPLLCFG0_DIVF_SHIFT) +# define PRCI_DDRPLLCFG0_DIVQ_SHIFT 15 +# define PRCI_DDRPLLCFG0_DIVQ_MASK (0x7 << PRCI_DDRPLLCFG0_DIVQ_SHIFT) +# define PRCI_DDRPLLCFG0_RANGE_SHIFT 18 +# define PRCI_DDRPLLCFG0_RANGE_MASK (0x7 << PRCI_DDRPLLCFG0_RANGE_SHIFT) +# define PRCI_DDRPLLCFG0_BYPASS_SHIFT 24 +# define PRCI_DDRPLLCFG0_BYPASS_MASK (0x1 << PRCI_DDRPLLCFG0_BYPASS_SHIFT) +# define PRCI_DDRPLLCFG0_FSE_SHIFT 25 +# define PRCI_DDRPLLCFG0_FSE_MASK (0x1 << PRCI_DDRPLLCFG0_FSE_SHIFT) +# define PRCI_DDRPLLCFG0_LOCK_SHIFT 31 +# define PRCI_DDRPLLCFG0_LOCK_MASK (0x1 << PRCI_DDRPLLCFG0_LOCK_SHIFT) + +/* DDRPLLCFG1 */ +#define PRCI_DDRPLLCFG1_OFFSET 0x10 +# define PRCI_DDRPLLCFG1_CKE_SHIFT 24 +# define PRCI_DDRPLLCFG1_CKE_MASK (0x1 << PRCI_DDRPLLCFG1_CKE_SHIFT) + +/* GEMGXLPLLCFG0 */ +#define PRCI_GEMGXLPLLCFG0_OFFSET 0x1c +# define PRCI_GEMGXLPLLCFG0_DIVR_SHIFT 0 +# define PRCI_GEMGXLPLLCFG0_DIVR_MASK (0x3f << PRCI_GEMGXLPLLCFG0_DIVR_SHIFT) +# define PRCI_GEMGXLPLLCFG0_DIVF_SHIFT 6 +# define PRCI_GEMGXLPLLCFG0_DIVF_MASK (0x1ff << PRCI_GEMGXLPLLCFG0_DIVF_SHIFT) +# define PRCI_GEMGXLPLLCFG0_DIVQ_SHIFT 15 +# define PRCI_GEMGXLPLLCFG0_DIVQ_MASK (0x7 << PRCI_GEMGXLPLLCFG0_DIVQ_SHIFT) +# define PRCI_GEMGXLPLLCFG0_RANGE_SHIFT 18 +# define PRCI_GEMGXLPLLCFG0_RANGE_MASK (0x7 << PRCI_GEMGXLPLLCFG0_RANGE_SHIFT) +# define PRCI_GEMGXLPLLCFG0_BYPASS_SHIFT 24 +# define PRCI_GEMGXLPLLCFG0_BYPASS_MASK (0x1 << PRCI_GEMGXLPLLCFG0_BYPASS_SHIFT) +# define PRCI_GEMGXLPLLCFG0_FSE_SHIFT 25 +# define PRCI_GEMGXLPLLCFG0_FSE_MASK (0x1 << PRCI_GEMGXLPLLCFG0_FSE_SHIFT) +# define PRCI_GEMGXLPLLCFG0_LOCK_SHIFT 31 +# define PRCI_GEMGXLPLLCFG0_LOCK_MASK (0x1 << PRCI_GEMGXLPLLCFG0_LOCK_SHIFT) + +/* GEMGXLPLLCFG1 */ +#define PRCI_GEMGXLPLLCFG1_OFFSET 0x20 +# define PRCI_GEMGXLPLLCFG1_CKE_SHIFT 24 +# define PRCI_GEMGXLPLLCFG1_CKE_MASK (0x1 << PRCI_GEMGXLPLLCFG1_CKE_SHIFT) + +/* CORECLKSEL */ +#define PRCI_CORECLKSEL_OFFSET 0x24 +# define PRCI_CORECLKSEL_CORECLKSEL_SHIFT 0 +# define PRCI_CORECLKSEL_CORECLKSEL_MASK (0x1 << PRCI_CORECLKSEL_CORECLKSEL_SHIFT) + +/* DEVICESRESETREG */ +#define PRCI_DEVICESRESETREG_OFFSET 0x28 +# define PRCI_DEVICESRESETREG_DDR_CTRL_RST_N_SHIFT 0 +# define PRCI_DEVICESRESETREG_DDR_CTRL_RST_N_MASK (0x1 << PRCI_DEVICESRESETREG_DDR_CTRL_RST_N_SHIFT) +# define PRCI_DEVICESRESETREG_DDR_AXI_RST_N_SHIFT 1 +# define PRCI_DEVICESRESETREG_DDR_AXI_RST_N_MASK (0x1 << PRCI_DEVICESRESETREG_DDR_AXI_RST_N_SHIFT) +# define PRCI_DEVICESRESETREG_DDR_AHB_RST_N_SHIFT 2 +# define PRCI_DEVICESRESETREG_DDR_AHB_RST_N_MASK (0x1 << PRCI_DEVICESRESETREG_DDR_AHB_RST_N_SHIFT) +# define PRCI_DEVICESRESETREG_DDR_PHY_RST_N_SHIFT 3 +# define PRCI_DEVICESRESETREG_DDR_PHY_RST_N_MASK (0x1 << PRCI_DEVICESRESETREG_DDR_PHY_RST_N_SHIFT) +# define PRCI_DEVICESRESETREG_GEMGXL_RST_N_SHIFT 5 +# define PRCI_DEVICESRESETREG_GEMGXL_RST_N_MASK (0x1 << PRCI_DEVICESRESETREG_GEMGXL_RST_N_SHIFT) + +/* CLKMUXSTATUSREG */ +#define PRCI_CLKMUXSTATUSREG_OFFSET 0x2c +# define PRCI_CLKMUXSTATUSREG_TLCLKSEL_STATUS_SHIFT 1 +# define PRCI_CLKMUXSTATUSREG_TLCLKSEL_STATUS_MASK (0x1 << PRCI_CLKMUXSTATUSREG_TLCLKSEL_STATUS_SHIFT) + +/* + * Private structures + */ + +/** + * struct __prci_data - per-device-instance data + * @va: base virtual address of the PRCI IP block + * @hw_clks: encapsulates struct clk_hw records + * + * PRCI per-device instance data + */ +struct __prci_data { + void __iomem *va; + struct clk_hw_onecell_data hw_clks; +}; + +/** + * struct __prci_wrpll_data - WRPLL configuration and integration data + * @c: WRPLL current configuration record + * @bypass: fn ptr to code to bypass the WRPLL (if applicable; else NULL) + * @no_bypass: fn ptr to code to not bypass the WRPLL (if applicable; else NULL) + * @cfg0_offs: WRPLL CFG0 register offset (in bytes) from the PRCI base address + * + * @bypass and @no_bypass are used for WRPLL instances that contain a separate + * external glitchless clock mux downstream from the PLL. The WRPLL internal + * bypass mux is not glitchless. + */ +struct __prci_wrpll_data { + struct analogbits_wrpll_cfg c; + void (*bypass)(struct __prci_data *pd); + void (*no_bypass)(struct __prci_data *pd); + u8 cfg0_offs; +}; + +/** + * struct __prci_clock - describes a clock device managed by PRCI + * @name: user-readable clock name string - should match the manual + * @parent_name: parent name for this clock + * @ops: struct clk_ops for the Linux clock framework to use for control + * @hw: Linux-private clock data + * @pwd: WRPLL-specific data, associated with this clock (if not NULL) + * @pd: PRCI-specific data associated with this clock (if not NULL) + * + * PRCI clock data. Used by the PRCI driver to register PRCI-provided + * clocks to the Linux clock infrastructure. + */ +struct __prci_clock { + const char *name; + const char *parent_name; + const struct clk_ops *ops; + struct clk_hw hw; + struct __prci_wrpll_data *pwd; + struct __prci_data *pd; +}; + +#define clk_hw_to_prci_clock(pwd) container_of(pwd, struct __prci_clock, hw) + +/* + * Private functions + */ + +/** + * __prci_readl() - read from a PRCI register + * @pd: PRCI context + * @offs: register offset to read from (in bytes, from PRCI base address) + * + * Read the register located at offset @offs from the base virtual + * address of the PRCI register target described by @pd, and return + * the value to the caller. + * + * Context: Any context. + * + * Return: the contents of the register described by @pd and @offs. + */ +static u32 __prci_readl(struct __prci_data *pd, u32 offs) +{ + return readl_relaxed(pd->va + offs); +} + +static void __prci_writel(u32 v, u32 offs, struct __prci_data *pd) +{ + return writel_relaxed(v, pd->va + offs); +} + +/* WRPLL-related private functions */ + +/** + * __prci_wrpll_unpack() - unpack WRPLL configuration registers into parameters + * @c: ptr to a struct analogbits_wrpll_cfg record to write config into + * @r: value read from the PRCI PLL configuration register + * + * Given a value @r read from an FU540 PRCI PLL configuration register, + * split it into fields and populate it into the WRPLL configuration record + * pointed to by @c. + * + * The COREPLLCFG0 macros are used below, but the other *PLLCFG0 macros + * have the same register layout. + * + * Context: Any context. + */ +static void __prci_wrpll_unpack(struct analogbits_wrpll_cfg *c, u32 r) +{ + u32 v; + + v = r & PRCI_COREPLLCFG0_DIVR_MASK; + v >>= PRCI_COREPLLCFG0_DIVR_SHIFT; + c->divr = v; + + v = r & PRCI_COREPLLCFG0_DIVF_MASK; + v >>= PRCI_COREPLLCFG0_DIVF_SHIFT; + c->divf = v; + + v = r & PRCI_COREPLLCFG0_DIVQ_MASK; + v >>= PRCI_COREPLLCFG0_DIVQ_SHIFT; + c->divq = v; + + v = r & PRCI_COREPLLCFG0_RANGE_MASK; + v >>= PRCI_COREPLLCFG0_RANGE_SHIFT; + c->range = v; + + c->flags &= (WRPLL_FLAGS_INT_FEEDBACK_MASK | + WRPLL_FLAGS_EXT_FEEDBACK_MASK); + + if (r & PRCI_COREPLLCFG0_FSE_MASK) + c->flags |= WRPLL_FLAGS_INT_FEEDBACK_MASK; + else + c->flags |= WRPLL_FLAGS_EXT_FEEDBACK_MASK; +} + +/** + * __prci_wrpll_pack() - pack PLL configuration parameters into a register value + * @c: pointer to a struct analogbits_wrpll_cfg record containing the PLL's cfg + * + * Using a set of WRPLL configuration values pointed to by @c, + * assemble a PRCI PLL configuration register value, and return it to + * the caller. + * + * Context: Any context. Caller must ensure that the contents of the + * record pointed to by @c do not change during the execution + * of this function. + * + * Returns: a value suitable for writing into a PRCI PLL configuration + * register + */ +static u32 __prci_wrpll_pack(struct analogbits_wrpll_cfg *c) +{ + u32 r = 0; + + r |= c->divr << PRCI_COREPLLCFG0_DIVR_SHIFT; + r |= c->divf << PRCI_COREPLLCFG0_DIVF_SHIFT; + r |= c->divq << PRCI_COREPLLCFG0_DIVQ_SHIFT; + r |= c->range << PRCI_COREPLLCFG0_RANGE_SHIFT; + if (c->flags & WRPLL_FLAGS_INT_FEEDBACK_MASK) + r |= PRCI_COREPLLCFG0_FSE_MASK; + + return r; +} + +/** + * __prci_wrpll_read_cfg() - read the WRPLL configuration from the PRCI + * @pd: PRCI context + * @pwd: PRCI WRPLL metadata + * + * Read the current configuration of the PLL identified by @pwd from + * the PRCI identified by @pd, and store it into the local configuration + * cache in @pwd. + * + * Context: Any context. Caller must prevent the records pointed to by + * @pd and @pwd from changing during execution. + */ +static void __prci_wrpll_read_cfg(struct __prci_data *pd, + struct __prci_wrpll_data *pwd) +{ + __prci_wrpll_unpack(&pwd->c, __prci_readl(pd, pwd->cfg0_offs)); +} + +/** + * __prci_wrpll_write_cfg() - write WRPLL configuration into the PRCI + * @pd: PRCI context + * @pwd: PRCI WRPLL metadata + * @c: WRPLL configuration record to write + * + * Write the WRPLL configuration described by @c into the WRPLL + * configuration register identified by @pwd in the PRCI instance + * described by @c. Make a cached copy of the WRPLL's current + * configuration so it can be used by other code. + * + * Context: Any context. Caller must prevent the records pointed to by + * @pd and @pwd from changing during execution. + */ +static void __prci_wrpll_write_cfg(struct __prci_data *pd, + struct __prci_wrpll_data *pwd, + struct analogbits_wrpll_cfg *c) +{ + __prci_writel(__prci_wrpll_pack(c), pwd->cfg0_offs, pd); + + memcpy(&pwd->c, c, sizeof(struct analogbits_wrpll_cfg)); +} + +/* Core clock mux control */ + +/** + * __prci_coreclksel_use_hfclk() - switch the CORECLK mux to output HFCLK + * @pd: struct __prci_data * for the PRCI containing the CORECLK mux reg + * + * Switch the CORECLK mux to the HFCLK input source; return once complete. + * + * Context: Any context. Caller must prevent concurrent changes to the + * PRCI_CORECLKSEL_OFFSET register. + */ +static void __prci_coreclksel_use_hfclk(struct __prci_data *pd) +{ + u32 r; + + r = __prci_readl(pd, PRCI_CORECLKSEL_OFFSET); + r |= PRCI_CORECLKSEL_CORECLKSEL_MASK; + __prci_writel(r, PRCI_CORECLKSEL_OFFSET, pd); + + r = __prci_readl(pd, PRCI_CORECLKSEL_OFFSET); /* barrier */ +} + +/** + * __prci_coreclksel_use_corepll() - switch the CORECLK mux to output COREPLL + * @pd: struct __prci_data * for the PRCI containing the CORECLK mux reg + * + * Switch the CORECLK mux to the PLL output clock; return once complete. + * + * Context: Any context. Caller must prevent concurrent changes to the + * PRCI_CORECLKSEL_OFFSET register. + */ +static void __prci_coreclksel_use_corepll(struct __prci_data *pd) +{ + u32 r; + + r = __prci_readl(pd, PRCI_CORECLKSEL_OFFSET); + r &= ~PRCI_CORECLKSEL_CORECLKSEL_MASK; + __prci_writel(r, PRCI_CORECLKSEL_OFFSET, pd); + + r = __prci_readl(pd, PRCI_CORECLKSEL_OFFSET); /* barrier */ +} + +/* + * Linux clock framework integration + * + * See the Linux clock framework documentation for more information on + * these functions. + */ + +static unsigned long sifive_fu540_prci_wrpll_recalc_rate(struct clk_hw *hw, + unsigned long parent_rate) +{ + struct __prci_clock *pc = clk_hw_to_prci_clock(hw); + struct __prci_wrpll_data *pwd = pc->pwd; + + return analogbits_wrpll_calc_output_rate(&pwd->c, parent_rate); +} + +static long sifive_fu540_prci_wrpll_round_rate(struct clk_hw *hw, + unsigned long rate, + unsigned long *parent_rate) +{ + struct __prci_clock *pc = clk_hw_to_prci_clock(hw); + struct __prci_wrpll_data *pwd = pc->pwd; + struct analogbits_wrpll_cfg c; + + memcpy(&c, &pwd->c, sizeof(c)); + + analogbits_wrpll_configure_for_rate(&c, rate, *parent_rate); + + return analogbits_wrpll_calc_output_rate(&c, *parent_rate); +} + +static int sifive_fu540_prci_wrpll_set_rate(struct clk_hw *hw, + unsigned long rate, + unsigned long parent_rate) +{ + struct __prci_clock *pc = clk_hw_to_prci_clock(hw); + struct __prci_wrpll_data *pwd = pc->pwd; + struct __prci_data *pd = pc->pd; + int r; + + r = analogbits_wrpll_configure_for_rate(&pwd->c, rate, parent_rate); + if (r) + return -ERANGE; + + if (pwd->bypass) + pwd->bypass(pd); + + __prci_wrpll_write_cfg(pd, pwd, &pwd->c); + + udelay(analogbits_wrpll_calc_max_lock_us(&pwd->c)); + + if (pwd->no_bypass) + pwd->no_bypass(pd); + + return 0; +} + +static const struct clk_ops sifive_fu540_prci_wrpll_clk_ops = { + .set_rate = sifive_fu540_prci_wrpll_set_rate, + .round_rate = sifive_fu540_prci_wrpll_round_rate, + .recalc_rate = sifive_fu540_prci_wrpll_recalc_rate, +}; + +static const struct clk_ops sifive_fu540_prci_wrpll_ro_clk_ops = { + .recalc_rate = sifive_fu540_prci_wrpll_recalc_rate, +}; + +/* TLCLKSEL clock integration */ + +static unsigned long sifive_fu540_prci_tlclksel_recalc_rate(struct clk_hw *hw, + unsigned long parent_rate) +{ + struct __prci_clock *pc = clk_hw_to_prci_clock(hw); + struct __prci_data *pd = pc->pd; + u32 v; + u8 div; + + v = __prci_readl(pd, PRCI_CLKMUXSTATUSREG_OFFSET); + v &= PRCI_CLKMUXSTATUSREG_TLCLKSEL_STATUS_MASK; + div = v ? 1 : 2; + + return div_u64(parent_rate, div); +} + +static const struct clk_ops sifive_fu540_prci_tlclksel_clk_ops = { + .recalc_rate = sifive_fu540_prci_tlclksel_recalc_rate, +}; + +/* + * PRCI integration data for each WRPLL instance + */ + +static struct __prci_wrpll_data __prci_corepll_data = { + .cfg0_offs = PRCI_COREPLLCFG0_OFFSET, + .bypass = __prci_coreclksel_use_hfclk, + .no_bypass = __prci_coreclksel_use_corepll, +}; + +static struct __prci_wrpll_data __prci_ddrpll_data = { + .cfg0_offs = PRCI_DDRPLLCFG0_OFFSET, +}; + +static struct __prci_wrpll_data __prci_gemgxlpll_data = { + .cfg0_offs = PRCI_GEMGXLPLLCFG0_OFFSET, +}; + +/* + * List of clock controls provided by the PRCI + */ + +static struct __prci_clock __prci_init_clocks[] = { + [PRCI_CLK_COREPLL] = { + .name = "corepll", + .parent_name = "hfclk", + .ops = &sifive_fu540_prci_wrpll_clk_ops, + .pwd = &__prci_corepll_data, + }, + [PRCI_CLK_DDRPLL] = { + .name = "ddrpll", + .parent_name = "hfclk", + .ops = &sifive_fu540_prci_wrpll_ro_clk_ops, + .pwd = &__prci_ddrpll_data, + }, + [PRCI_CLK_GEMGXLPLL] = { + .name = "gemgxlpll", + .parent_name = "hfclk", + .ops = &sifive_fu540_prci_wrpll_clk_ops, + .pwd = &__prci_gemgxlpll_data, + }, + [PRCI_CLK_TLCLK] = { + .name = "tlclk", + .parent_name = "corepll", + .ops = &sifive_fu540_prci_tlclksel_clk_ops, + }, +}; + +/** + * __prci_register_clocks() - register clock controls in the PRCI with Linux + * @dev: Linux struct device * + * + * Register the list of clock controls described in __prci_init_plls[] with + * the Linux clock framework. + * + * Return: 0 upon success or a negative Linux error code upon failure. + */ +static int __prci_register_clocks(struct device *dev) +{ + struct __prci_data *pd = dev_get_drvdata(dev); + struct clk_init_data init; + struct __prci_clock *pic; + int parent_count, i, clk_hw_count, r; + + parent_count = of_clk_get_parent_count(dev->of_node); + if (parent_count != EXPECTED_CLK_PARENT_COUNT) { + dev_err(dev, "expected two parent clocks, only found %d\n", + parent_count); + return -EINVAL; + } + + memset(&init, 0, sizeof(struct clk_init_data)); + + /* Register PLLs */ + clk_hw_count = sizeof(__prci_init_clocks) / sizeof(struct __prci_clock); + + for (i = 0; i < clk_hw_count; ++i) { + pic = &__prci_init_clocks[i]; + + init.name = pic->name; + init.parent_names = (const char *[]) { pic->parent_name }; + init.num_parents = 1; + init.ops = pic->ops; + init.flags = CLK_IGNORE_UNUSED; + pic->hw.init = &init; + + pic->pd = pd; + + if (pic->pwd) + __prci_wrpll_read_cfg(pd, pic->pwd); + + r = devm_clk_hw_register(dev, &pic->hw); + if (r) { + dev_warn(dev, "Failed to register clock %s: %d\n", + init.name, r); + return r; + } + + r = clk_hw_register_clkdev(&pic->hw, pic->name, dev_name(dev)); + if (r) { + dev_warn(dev, "Failed to register clkdev for %s: %d\n", + init.name, r); + return r; + } + + pd->hw_clks.hws[i] = &pic->hw; + } + + pd->hw_clks.num = i; + + r = devm_of_clk_add_hw_provider(dev, of_clk_hw_onecell_get, + &pd->hw_clks); + if (r) { + dev_err(dev, "could not add hw_provider: %d\n", r); + return -EINVAL; + } + + return 0; +} + +/* + * Linux device model integration + * + * See the Linux device model documentation for more information about + * these functions. + */ +static int sifive_fu540_prci_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct resource *res; + struct __prci_data *pd; + int r; + + pd = devm_kzalloc(dev, sizeof(struct __prci_data), GFP_KERNEL); + if (!pd) + return -ENOMEM; + + dev_set_drvdata(dev, pd); + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + pd->va = devm_ioremap_resource(dev, res); + if (IS_ERR(pd->va)) + return PTR_ERR(pd->va); + + r = __prci_register_clocks(dev); + if (r) { + dev_err(dev, "could not register clocks: %d\n", r); + return -EINVAL; + } + + dev_info(dev, "SiFive FU540 PRCI probed\n"); + + return 0; +} + +static const struct of_device_id sifive_fu540_prci_of_match[] = { + { .compatible = "sifive,fu540-c000-prci0", }, + {} +}; + +static struct platform_driver sifive_fu540_prci_driver = { + .driver = { + .name = "sifive-fu540-prci", + .of_match_table = sifive_fu540_prci_of_match, + }, + .probe = sifive_fu540_prci_probe, +}; + +static int __init sifive_fu540_prci_init(void) +{ + return platform_driver_register(&sifive_fu540_prci_driver); +} +core_initcall(sifive_fu540_prci_init); diff --git a/include/linux/clk/sifive-fu540-prci.h b/include/linux/clk/sifive-fu540-prci.h new file mode 100644 index 000000000000..5d03eae7d4ef --- /dev/null +++ b/include/linux/clk/sifive-fu540-prci.h @@ -0,0 +1,27 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Copyright (C) 2018 SiFive, Inc. + * Wesley Terpstra + * Paul Walmsley + * + * 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. + * + * 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 __LINUX_CLK_SIFIVE_FU540_PRCI_H +#define __LINUX_CLK_SIFIVE_FU540_PRCI_H + +/* Clock indexes for use by Device Tree data */ + +#define PRCI_CLK_COREPLL 0 +#define PRCI_CLK_DDRPLL 1 +#define PRCI_CLK_GEMGXLPLL 2 +#define PRCI_CLK_TLCLK 3 + +#endif -- 2.19.1
