diff options
Diffstat (limited to 'kernel/drivers/clk/shmobile/clk-emev2.c')
| -rw-r--r-- | kernel/drivers/clk/shmobile/clk-emev2.c | 104 |
1 files changed, 104 insertions, 0 deletions
diff --git a/kernel/drivers/clk/shmobile/clk-emev2.c b/kernel/drivers/clk/shmobile/clk-emev2.c new file mode 100644 index 000000000..6c7c929c7 --- /dev/null +++ b/kernel/drivers/clk/shmobile/clk-emev2.c @@ -0,0 +1,104 @@ +/* + * EMMA Mobile EV2 common clock framework support + * + * Copyright (C) 2013 Takashi Yoshii <takashi.yoshii.ze@renesas.com> + * Copyright (C) 2012 Magnus Damm + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; version 2 of the License. + * + * 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. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA + */ +#include <linux/clk-provider.h> +#include <linux/clkdev.h> +#include <linux/io.h> +#include <linux/of.h> +#include <linux/of_address.h> + +/* EMEV2 SMU registers */ +#define USIAU0_RSTCTRL 0x094 +#define USIBU1_RSTCTRL 0x0ac +#define USIBU2_RSTCTRL 0x0b0 +#define USIBU3_RSTCTRL 0x0b4 +#define STI_RSTCTRL 0x124 +#define STI_CLKSEL 0x688 + +static DEFINE_SPINLOCK(lock); + +/* not pretty, but hey */ +void __iomem *smu_base; + +static void __init emev2_smu_write(unsigned long value, int offs) +{ + BUG_ON(!smu_base || (offs >= PAGE_SIZE)); + writel_relaxed(value, smu_base + offs); +} + +static const struct of_device_id smu_id[] __initconst = { + { .compatible = "renesas,emev2-smu", }, + {}, +}; + +static void __init emev2_smu_init(void) +{ + struct device_node *np; + + np = of_find_matching_node(NULL, smu_id); + BUG_ON(!np); + smu_base = of_iomap(np, 0); + BUG_ON(!smu_base); + of_node_put(np); + + /* setup STI timer to run on 32.768 kHz and deassert reset */ + emev2_smu_write(0, STI_CLKSEL); + emev2_smu_write(1, STI_RSTCTRL); + + /* deassert reset for UART0->UART3 */ + emev2_smu_write(2, USIAU0_RSTCTRL); + emev2_smu_write(2, USIBU1_RSTCTRL); + emev2_smu_write(2, USIBU2_RSTCTRL); + emev2_smu_write(2, USIBU3_RSTCTRL); +} + +static void __init emev2_smu_clkdiv_init(struct device_node *np) +{ + u32 reg[2]; + struct clk *clk; + const char *parent_name = of_clk_get_parent_name(np, 0); + if (WARN_ON(of_property_read_u32_array(np, "reg", reg, 2))) + return; + if (!smu_base) + emev2_smu_init(); + clk = clk_register_divider(NULL, np->name, parent_name, 0, + smu_base + reg[0], reg[1], 8, 0, &lock); + of_clk_add_provider(np, of_clk_src_simple_get, clk); + clk_register_clkdev(clk, np->name, NULL); + pr_debug("## %s %s %p\n", __func__, np->name, clk); +} +CLK_OF_DECLARE(emev2_smu_clkdiv, "renesas,emev2-smu-clkdiv", + emev2_smu_clkdiv_init); + +static void __init emev2_smu_gclk_init(struct device_node *np) +{ + u32 reg[2]; + struct clk *clk; + const char *parent_name = of_clk_get_parent_name(np, 0); + if (WARN_ON(of_property_read_u32_array(np, "reg", reg, 2))) + return; + if (!smu_base) + emev2_smu_init(); + clk = clk_register_gate(NULL, np->name, parent_name, 0, + smu_base + reg[0], reg[1], 0, &lock); + of_clk_add_provider(np, of_clk_src_simple_get, clk); + clk_register_clkdev(clk, np->name, NULL); + pr_debug("## %s %s %p\n", __func__, np->name, clk); +} +CLK_OF_DECLARE(emev2_smu_gclk, "renesas,emev2-smu-gclk", emev2_smu_gclk_init); |