1/* 2 * EMMA Mobile EV2 common clock framework support 3 * 4 * Copyright (C) 2013 Takashi Yoshii <takashi.yoshii.ze@renesas.com> 5 * Copyright (C) 2012 Magnus Damm 6 * 7 * This program is free software; you can redistribute it and/or modify 8 * it under the terms of the GNU General Public License as published by 9 * the Free Software Foundation; version 2 of the License. 10 * 11 * This program is distributed in the hope that it will be useful, 12 * but WITHOUT ANY WARRANTY; without even the implied warranty of 13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 14 * GNU General Public License for more details. 15 * 16 * You should have received a copy of the GNU General Public License 17 * along with this program; if not, write to the Free Software 18 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA 19 */ 20#include <linux/clk-provider.h> 21#include <linux/clkdev.h> 22#include <linux/io.h> 23#include <linux/of.h> 24#include <linux/of_address.h> 25 26/* EMEV2 SMU registers */ 27#define USIAU0_RSTCTRL 0x094 28#define USIBU1_RSTCTRL 0x0ac 29#define USIBU2_RSTCTRL 0x0b0 30#define USIBU3_RSTCTRL 0x0b4 31#define STI_RSTCTRL 0x124 32#define STI_CLKSEL 0x688 33 34static DEFINE_SPINLOCK(lock); 35 36/* not pretty, but hey */ 37void __iomem *smu_base; 38 39static void __init emev2_smu_write(unsigned long value, int offs) 40{ 41 BUG_ON(!smu_base || (offs >= PAGE_SIZE)); 42 writel_relaxed(value, smu_base + offs); 43} 44 45static const struct of_device_id smu_id[] __initconst = { 46 { .compatible = "renesas,emev2-smu", }, 47 {}, 48}; 49 50static void __init emev2_smu_init(void) 51{ 52 struct device_node *np; 53 54 np = of_find_matching_node(NULL, smu_id); 55 BUG_ON(!np); 56 smu_base = of_iomap(np, 0); 57 BUG_ON(!smu_base); 58 of_node_put(np); 59 60 /* setup STI timer to run on 32.768 kHz and deassert reset */ 61 emev2_smu_write(0, STI_CLKSEL); 62 emev2_smu_write(1, STI_RSTCTRL); 63 64 /* deassert reset for UART0->UART3 */ 65 emev2_smu_write(2, USIAU0_RSTCTRL); 66 emev2_smu_write(2, USIBU1_RSTCTRL); 67 emev2_smu_write(2, USIBU2_RSTCTRL); 68 emev2_smu_write(2, USIBU3_RSTCTRL); 69} 70 71static void __init emev2_smu_clkdiv_init(struct device_node *np) 72{ 73 u32 reg[2]; 74 struct clk *clk; 75 const char *parent_name = of_clk_get_parent_name(np, 0); 76 if (WARN_ON(of_property_read_u32_array(np, "reg", reg, 2))) 77 return; 78 if (!smu_base) 79 emev2_smu_init(); 80 clk = clk_register_divider(NULL, np->name, parent_name, 0, 81 smu_base + reg[0], reg[1], 8, 0, &lock); 82 of_clk_add_provider(np, of_clk_src_simple_get, clk); 83 clk_register_clkdev(clk, np->name, NULL); 84 pr_debug("## %s %s %p\n", __func__, np->name, clk); 85} 86CLK_OF_DECLARE(emev2_smu_clkdiv, "renesas,emev2-smu-clkdiv", 87 emev2_smu_clkdiv_init); 88 89static void __init emev2_smu_gclk_init(struct device_node *np) 90{ 91 u32 reg[2]; 92 struct clk *clk; 93 const char *parent_name = of_clk_get_parent_name(np, 0); 94 if (WARN_ON(of_property_read_u32_array(np, "reg", reg, 2))) 95 return; 96 if (!smu_base) 97 emev2_smu_init(); 98 clk = clk_register_gate(NULL, np->name, parent_name, 0, 99 smu_base + reg[0], reg[1], 0, &lock); 100 of_clk_add_provider(np, of_clk_src_simple_get, clk); 101 clk_register_clkdev(clk, np->name, NULL); 102 pr_debug("## %s %s %p\n", __func__, np->name, clk); 103} 104CLK_OF_DECLARE(emev2_smu_gclk, "renesas,emev2-smu-gclk", emev2_smu_gclk_init); 105