| // SPDX-License-Identifier: GPL-2.0-only |
| /* |
| * Copyright (C) 2015 Altera Corporation. All rights reserved |
| */ |
| #include <linux/slab.h> |
| #include <linux/clk-provider.h> |
| #include <linux/io.h> |
| #include <linux/of.h> |
| |
| #include "clk.h" |
| |
| #define CLK_MGR_FREE_SHIFT 16 |
| #define CLK_MGR_FREE_MASK 0x7 |
| |
| #define SOCFPGA_MPU_FREE_CLK "mpu_free_clk" |
| #define SOCFPGA_NOC_FREE_CLK "noc_free_clk" |
| #define SOCFPGA_SDMMC_FREE_CLK "sdmmc_free_clk" |
| #define to_socfpga_periph_clk(p) container_of(p, struct socfpga_periph_clk, hw.hw) |
| |
| static unsigned long clk_periclk_recalc_rate(struct clk_hw *hwclk, |
| unsigned long parent_rate) |
| { |
| struct socfpga_periph_clk *socfpgaclk = to_socfpga_periph_clk(hwclk); |
| u32 div; |
| |
| if (socfpgaclk->fixed_div) { |
| div = socfpgaclk->fixed_div; |
| } else if (socfpgaclk->div_reg) { |
| div = readl(socfpgaclk->div_reg) >> socfpgaclk->shift; |
| div &= GENMASK(socfpgaclk->width - 1, 0); |
| div += 1; |
| } else { |
| div = ((readl(socfpgaclk->hw.reg) & 0x7ff) + 1); |
| } |
| |
| return parent_rate / div; |
| } |
| |
| static u8 clk_periclk_get_parent(struct clk_hw *hwclk) |
| { |
| struct socfpga_periph_clk *socfpgaclk = to_socfpga_periph_clk(hwclk); |
| u32 clk_src; |
| |
| clk_src = readl(socfpgaclk->hw.reg); |
| if (streq(hwclk->init->name, SOCFPGA_MPU_FREE_CLK) || |
| streq(hwclk->init->name, SOCFPGA_NOC_FREE_CLK) || |
| streq(hwclk->init->name, SOCFPGA_SDMMC_FREE_CLK)) |
| return (clk_src >> CLK_MGR_FREE_SHIFT) & |
| CLK_MGR_FREE_MASK; |
| else |
| return 0; |
| } |
| |
| static const struct clk_ops periclk_ops = { |
| .recalc_rate = clk_periclk_recalc_rate, |
| .get_parent = clk_periclk_get_parent, |
| }; |
| |
| static __init void __socfpga_periph_init(struct device_node *node, |
| const struct clk_ops *ops) |
| { |
| u32 reg; |
| struct clk *clk; |
| struct socfpga_periph_clk *periph_clk; |
| const char *clk_name = node->name; |
| const char *parent_name[SOCFPGA_MAX_PARENTS]; |
| struct clk_init_data init; |
| int rc; |
| u32 fixed_div; |
| u32 div_reg[3]; |
| |
| of_property_read_u32(node, "reg", ®); |
| |
| periph_clk = kzalloc(sizeof(*periph_clk), GFP_KERNEL); |
| if (WARN_ON(!periph_clk)) |
| return; |
| |
| periph_clk->hw.reg = clk_mgr_a10_base_addr + reg; |
| |
| rc = of_property_read_u32_array(node, "div-reg", div_reg, 3); |
| if (!rc) { |
| periph_clk->div_reg = clk_mgr_a10_base_addr + div_reg[0]; |
| periph_clk->shift = div_reg[1]; |
| periph_clk->width = div_reg[2]; |
| } else { |
| periph_clk->div_reg = NULL; |
| } |
| |
| rc = of_property_read_u32(node, "fixed-divider", &fixed_div); |
| if (rc) |
| periph_clk->fixed_div = 0; |
| else |
| periph_clk->fixed_div = fixed_div; |
| |
| 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); |
| init.parent_names = parent_name; |
| |
| periph_clk->hw.hw.init = &init; |
| |
| clk = clk_register(NULL, &periph_clk->hw.hw); |
| if (WARN_ON(IS_ERR(clk))) { |
| kfree(periph_clk); |
| return; |
| } |
| rc = of_clk_add_provider(node, of_clk_src_simple_get, clk); |
| if (rc < 0) { |
| pr_err("Could not register clock provider for node:%s\n", |
| clk_name); |
| goto err_clk; |
| } |
| |
| return; |
| |
| err_clk: |
| clk_unregister(clk); |
| } |
| |
| void __init socfpga_a10_periph_init(struct device_node *node) |
| { |
| __socfpga_periph_init(node, &periclk_ops); |
| } |