diff options
Diffstat (limited to 'drivers/clk/socfpga/clk-gate.c')
| -rw-r--r-- | drivers/clk/socfpga/clk-gate.c | 223 |
1 files changed, 223 insertions, 0 deletions
diff --git a/drivers/clk/socfpga/clk-gate.c b/drivers/clk/socfpga/clk-gate.c new file mode 100644 index 0000000000..0a5a95e026 --- /dev/null +++ b/drivers/clk/socfpga/clk-gate.c @@ -0,0 +1,223 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Copyright 2011-2012 Calxeda, Inc. + * Copyright (C) 2012-2013 Altera Corporation <www.altera.com> + * + * Based from clk-highbank.c + */ +#include <linux/slab.h> +#include <linux/clk-provider.h> +#include <linux/io.h> +#include <linux/mfd/syscon.h> +#include <linux/of.h> +#include <linux/regmap.h> + +#include "clk.h" + +#define SOCFPGA_L4_MP_CLK "l4_mp_clk" +#define SOCFPGA_L4_SP_CLK "l4_sp_clk" +#define SOCFPGA_NAND_CLK "nand_clk" +#define SOCFPGA_NAND_X_CLK "nand_x_clk" +#define SOCFPGA_MMC_CLK "sdmmc_clk" +#define SOCFPGA_GPIO_DB_CLK_OFFSET 0xA8 + +#define to_socfpga_gate_clk(p) container_of(p, struct socfpga_gate_clk, hw.hw) + +/* SDMMC Group for System Manager defines */ +#define SYSMGR_SDMMCGRP_CTRL_OFFSET 0x108 + +static u8 socfpga_clk_get_parent(struct clk_hw *hwclk) +{ + u32 l4_src; + u32 perpll_src; + const char *name = clk_hw_get_name(hwclk); + + if (streq(name, SOCFPGA_L4_MP_CLK)) { + l4_src = readl(clk_mgr_base_addr + CLKMGR_L4SRC); + return l4_src & 0x1; + } + if (streq(name, SOCFPGA_L4_SP_CLK)) { + l4_src = readl(clk_mgr_base_addr + CLKMGR_L4SRC); + return !!(l4_src & 2); + } + + perpll_src = readl(clk_mgr_base_addr + CLKMGR_PERPLL_SRC); + if (streq(name, SOCFPGA_MMC_CLK)) + return perpll_src & 0x3; + if (streq(name, SOCFPGA_NAND_CLK) || + streq(name, SOCFPGA_NAND_X_CLK)) + return (perpll_src >> 2) & 3; + + /* QSPI clock */ + return (perpll_src >> 4) & 3; + +} + +static int socfpga_clk_set_parent(struct clk_hw *hwclk, u8 parent) +{ + u32 src_reg; + const char *name = clk_hw_get_name(hwclk); + + if (streq(name, SOCFPGA_L4_MP_CLK)) { + src_reg = readl(clk_mgr_base_addr + CLKMGR_L4SRC); + src_reg &= ~0x1; + src_reg |= parent; + writel(src_reg, clk_mgr_base_addr + CLKMGR_L4SRC); + } else if (streq(name, SOCFPGA_L4_SP_CLK)) { + src_reg = readl(clk_mgr_base_addr + CLKMGR_L4SRC); + src_reg &= ~0x2; + src_reg |= (parent << 1); + writel(src_reg, clk_mgr_base_addr + CLKMGR_L4SRC); + } else { + src_reg = readl(clk_mgr_base_addr + CLKMGR_PERPLL_SRC); + if (streq(name, SOCFPGA_MMC_CLK)) { + src_reg &= ~0x3; + src_reg |= parent; + } else if (streq(name, SOCFPGA_NAND_CLK) || + streq(name, SOCFPGA_NAND_X_CLK)) { + src_reg &= ~0xC; + src_reg |= (parent << 2); + } else {/* QSPI clock */ + src_reg &= ~0x30; + src_reg |= (parent << 4); + } + writel(src_reg, clk_mgr_base_addr + CLKMGR_PERPLL_SRC); + } + + return 0; +} + +static u32 socfpga_clk_get_div(struct socfpga_gate_clk *socfpgaclk) +{ + u32 div = 1, val; + + if (socfpgaclk->fixed_div) + div = socfpgaclk->fixed_div; + else if (socfpgaclk->div_reg) { + val = readl(socfpgaclk->div_reg) >> socfpgaclk->shift; + val &= GENMASK(socfpgaclk->width - 1, 0); + /* Check for GPIO_DB_CLK by its offset */ + if ((uintptr_t) socfpgaclk->div_reg & SOCFPGA_GPIO_DB_CLK_OFFSET) + div = val + 1; + else + div = (1 << val); + } + + return div; +} + +static unsigned long socfpga_clk_recalc_rate(struct clk_hw *hwclk, + unsigned long parent_rate) +{ + struct socfpga_gate_clk *socfpgaclk = to_socfpga_gate_clk(hwclk); + u32 div = socfpga_clk_get_div(socfpgaclk); + + return parent_rate / div; +} + + +static int socfpga_clk_determine_rate(struct clk_hw *hwclk, + struct clk_rate_request *req) +{ + struct socfpga_gate_clk *socfpgaclk = to_socfpga_gate_clk(hwclk); + u32 div = socfpga_clk_get_div(socfpgaclk); + + req->rate = req->best_parent_rate / div; + + return 0; +} + +static struct clk_ops gateclk_ops = { + .recalc_rate = socfpga_clk_recalc_rate, + .determine_rate = socfpga_clk_determine_rate, + .get_parent = socfpga_clk_get_parent, + .set_parent = socfpga_clk_set_parent, +}; + +void __init socfpga_gate_init(struct device_node *node) +{ + u32 clk_gate[2]; + u32 div_reg[3]; + u32 fixed_div; + struct clk_hw *hw_clk; + struct socfpga_gate_clk *socfpga_clk; + const char *clk_name = node->name; + const char *parent_name[SOCFPGA_MAX_PARENTS]; + struct clk_init_data init; + struct clk_ops *ops; + int rc; + + socfpga_clk = kzalloc(sizeof(*socfpga_clk), GFP_KERNEL); + if (WARN_ON(!socfpga_clk)) + return; + + ops = kmemdup(&gateclk_ops, sizeof(gateclk_ops), GFP_KERNEL); + if (WARN_ON(!ops)) + goto err_kmemdup; + + rc = of_property_read_u32_array(node, "clk-gate", clk_gate, 2); + if (rc) + clk_gate[0] = 0; + + if (clk_gate[0]) { + socfpga_clk->hw.reg = clk_mgr_base_addr + clk_gate[0]; + socfpga_clk->hw.bit_idx = clk_gate[1]; + + ops->enable = clk_gate_ops.enable; + ops->disable = clk_gate_ops.disable; + } + + rc = of_property_read_u32(node, "fixed-divider", &fixed_div); + if (rc) + socfpga_clk->fixed_div = 0; + else + socfpga_clk->fixed_div = fixed_div; + + rc = of_property_read_u32_array(node, "div-reg", div_reg, 3); + if (!rc) { + socfpga_clk->div_reg = clk_mgr_base_addr + div_reg[0]; + socfpga_clk->shift = div_reg[1]; + socfpga_clk->width = div_reg[2]; + } else { + socfpga_clk->div_reg = NULL; + } + + of_property_read_string(node, "clock-output-names", &clk_name); + + init.name = clk_name; + init.ops = ops; + init.flags = 0; + + init.num_parents = of_clk_parent_fill(node, parent_name, SOCFPGA_MAX_PARENTS); + if (init.num_parents < 2) { + ops->get_parent = NULL; + ops->set_parent = NULL; + } + + init.parent_names = parent_name; + socfpga_clk->hw.hw.init = &init; + + hw_clk = &socfpga_clk->hw.hw; + + rc = clk_hw_register(NULL, hw_clk); + if (rc) { + pr_err("Could not register clock:%s\n", clk_name); + goto err_clk_hw_register; + } + + rc = of_clk_add_hw_provider(node, of_clk_hw_simple_get, hw_clk); + if (rc) { + pr_err("Could not register clock provider for node:%s\n", + clk_name); + goto err_of_clk_add_hw_provider; + } + + return; + +err_of_clk_add_hw_provider: + clk_hw_unregister(hw_clk); +err_clk_hw_register: + kfree(ops); +err_kmemdup: + kfree(socfpga_clk); +} |