forked from Minki/linux
92ca6a8ce9
Device tree clock binding document for EMMA Mobile EV2 SMU, And Common clock framework based implementation of it. Following nodes are defined to describe clock tree. - renesas,emev2-smu - renesas,emev2-smu-clkdiv - renesas,emev2-smu-gclk These bindings are designed manually based on 19UH0037EJ1000_SMU : System Management Unit User's Manual So far, reparent is not implemented, and is fixed to index #0. Clock tree description is not included, and should be provided by device-tree. Signed-off-by: Takashi Yoshii <takasi-y@ops.dti.ne.jp> Acked-by: Magnus Damm <damm@opensource.se> Signed-off-by: Simon Horman <horms+renesas@verge.net.au>
105 lines
3.1 KiB
C
105 lines
3.1 KiB
C
/*
|
|
* 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);
|