// SPDX-License-Identifier: GPL-2.0 /* * RZ/A1 Core CPG Clocks * * Copyright (C) 2013 Ideas On Board SPRL * Copyright (C) 2014 Wolfram Sang, Sang Engineering <wsa@sang-engineering.com> */ #include <linux/clk-provider.h> #include <linux/clk/renesas.h> #include <linux/init.h> #include <linux/io.h> #include <linux/kernel.h> #include <linux/of.h> #include <linux/of_address.h> #include <linux/slab.h> #define CPG_FRQCR 0x10 #define CPG_FRQCR2 0x14 #define PPR0 0xFCFE3200 #define PIBC0 0xFCFE7000 #define MD_CLK(x) ((x >> 2) & 1) /* P0_2 */ /* ----------------------------------------------------------------------------- * Initialization */ static u16 __init rz_cpg_read_mode_pins(void) { void __iomem *ppr0, *pibc0; u16 modes; ppr0 = ioremap(PPR0, 2); pibc0 = ioremap(PIBC0, 2); BUG_ON(!ppr0 || !pibc0); iowrite16(4, pibc0); /* enable input buffer */ modes = ioread16(ppr0); iounmap(ppr0); iounmap(pibc0); return modes; } static struct clk * __init rz_cpg_register_clock(struct device_node *np, void __iomem *base, const char *name) { u32 val; unsigned mult; static const unsigned frqcr_tab[4] = { 3, 2, 0, 1 }; if (strcmp(name, "pll") == 0) { unsigned int cpg_mode = MD_CLK(rz_cpg_read_mode_pins()); const char *parent_name = of_clk_get_parent_name(np, cpg_mode); mult = cpg_mode ? (32 / 4) : 30; return clk_register_fixed_factor(NULL, name, parent_name, 0, mult, 1); } /* If mapping regs failed, skip non-pll clocks. System will boot anyhow */ if (!base) return ERR_PTR(-ENXIO); /* FIXME:"i" and "g" are variable clocks with non-integer dividers (e.g. 2/3) * and the constraint that always g <= i. To get the rz platform started, * let them run at fixed current speed and implement the details later. */ if (strcmp(name, "i") == 0) val = (readl(base + CPG_FRQCR) >> 8) & 3; else if (strcmp(name, "g") == 0) val = readl(base + CPG_FRQCR2) & 3; else return ERR_PTR(-EINVAL); mult = frqcr_tab[val]; return clk_register_fixed_factor(NULL, name, "pll", 0, mult, 3); } static void __init rz_cpg_clocks_init(struct device_node *np) { struct clk_onecell_data *data; struct clk **clks; void __iomem *base; unsigned i; int num_clks; num_clks = of_property_count_strings(np, "clock-output-names"); if (WARN(num_clks <= 0, "can't count CPG clocks\n")) return; data = kzalloc(sizeof(*data), GFP_KERNEL); clks = kcalloc(num_clks, sizeof(*clks), GFP_KERNEL); BUG_ON(!data || !clks); data->clks = clks; data->clk_num = num_clks; base = of_iomap(np, 0); for (i = 0; i < num_clks; ++i) { const char *name; struct clk *clk; of_property_read_string_index(np, "clock-output-names", i, &name); clk = rz_cpg_register_clock(np, base, name); if (IS_ERR(clk)) pr_err("%s: failed to register %pOFn %s clock (%ld)\n", __func__, np, name, PTR_ERR(clk)); else data->clks[i] = clk; } of_clk_add_provider(np, of_clk_src_onecell_get, data); cpg_mstp_add_clk_domain(np); } CLK_OF_DECLARE(rz_cpg_clks, "renesas,rz-cpg-clocks", rz_cpg_clocks_init);