linux/drivers/clk/tegra/clk.c
Mikko Perttunen 4236e752f1 clk: tegra: Implement reset control reset
For completeness, also implement this reset framework API for Tegra.

Signed-off-by: Mikko Perttunen <mperttunen@nvidia.com>
Reviewed-by: Peter De Schrijver <pdeschrijver@nvidia.com>
Reviewed-by: Arto Merilainen <amerilainen@nvidia.com>
Signed-off-by: Peter De Schrijver <pdeschrijver@nvidia.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>
2017-03-20 14:15:31 +01:00

369 lines
9.1 KiB
C

/*
* Copyright (c) 2012, NVIDIA CORPORATION. All rights reserved.
*
* This program is free software; you can redistribute it and/or modify it
* under the terms and conditions of the GNU General Public License,
* version 2, as published by the Free Software Foundation.
*
* This program is distributed in the hope 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, see <http://www.gnu.org/licenses/>.
*/
#include <linux/clkdev.h>
#include <linux/clk.h>
#include <linux/clk-provider.h>
#include <linux/delay.h>
#include <linux/of.h>
#include <linux/clk/tegra.h>
#include <linux/reset-controller.h>
#include <soc/tegra/fuse.h>
#include "clk.h"
#define CLK_OUT_ENB_L 0x010
#define CLK_OUT_ENB_H 0x014
#define CLK_OUT_ENB_U 0x018
#define CLK_OUT_ENB_V 0x360
#define CLK_OUT_ENB_W 0x364
#define CLK_OUT_ENB_X 0x280
#define CLK_OUT_ENB_Y 0x298
#define CLK_OUT_ENB_SET_L 0x320
#define CLK_OUT_ENB_CLR_L 0x324
#define CLK_OUT_ENB_SET_H 0x328
#define CLK_OUT_ENB_CLR_H 0x32c
#define CLK_OUT_ENB_SET_U 0x330
#define CLK_OUT_ENB_CLR_U 0x334
#define CLK_OUT_ENB_SET_V 0x440
#define CLK_OUT_ENB_CLR_V 0x444
#define CLK_OUT_ENB_SET_W 0x448
#define CLK_OUT_ENB_CLR_W 0x44c
#define CLK_OUT_ENB_SET_X 0x284
#define CLK_OUT_ENB_CLR_X 0x288
#define CLK_OUT_ENB_SET_Y 0x29c
#define CLK_OUT_ENB_CLR_Y 0x2a0
#define RST_DEVICES_L 0x004
#define RST_DEVICES_H 0x008
#define RST_DEVICES_U 0x00C
#define RST_DEVICES_V 0x358
#define RST_DEVICES_W 0x35C
#define RST_DEVICES_X 0x28C
#define RST_DEVICES_Y 0x2a4
#define RST_DEVICES_SET_L 0x300
#define RST_DEVICES_CLR_L 0x304
#define RST_DEVICES_SET_H 0x308
#define RST_DEVICES_CLR_H 0x30c
#define RST_DEVICES_SET_U 0x310
#define RST_DEVICES_CLR_U 0x314
#define RST_DEVICES_SET_V 0x430
#define RST_DEVICES_CLR_V 0x434
#define RST_DEVICES_SET_W 0x438
#define RST_DEVICES_CLR_W 0x43c
#define RST_DEVICES_SET_X 0x290
#define RST_DEVICES_CLR_X 0x294
#define RST_DEVICES_SET_Y 0x2a8
#define RST_DEVICES_CLR_Y 0x2ac
/* Global data of Tegra CPU CAR ops */
static struct tegra_cpu_car_ops dummy_car_ops;
struct tegra_cpu_car_ops *tegra_cpu_car_ops = &dummy_car_ops;
int *periph_clk_enb_refcnt;
static int periph_banks;
static struct clk **clks;
static int clk_num;
static struct clk_onecell_data clk_data;
/* Handlers for SoC-specific reset lines */
static int (*special_reset_assert)(unsigned long);
static int (*special_reset_deassert)(unsigned long);
static unsigned int num_special_reset;
static const struct tegra_clk_periph_regs periph_regs[] = {
[0] = {
.enb_reg = CLK_OUT_ENB_L,
.enb_set_reg = CLK_OUT_ENB_SET_L,
.enb_clr_reg = CLK_OUT_ENB_CLR_L,
.rst_reg = RST_DEVICES_L,
.rst_set_reg = RST_DEVICES_SET_L,
.rst_clr_reg = RST_DEVICES_CLR_L,
},
[1] = {
.enb_reg = CLK_OUT_ENB_H,
.enb_set_reg = CLK_OUT_ENB_SET_H,
.enb_clr_reg = CLK_OUT_ENB_CLR_H,
.rst_reg = RST_DEVICES_H,
.rst_set_reg = RST_DEVICES_SET_H,
.rst_clr_reg = RST_DEVICES_CLR_H,
},
[2] = {
.enb_reg = CLK_OUT_ENB_U,
.enb_set_reg = CLK_OUT_ENB_SET_U,
.enb_clr_reg = CLK_OUT_ENB_CLR_U,
.rst_reg = RST_DEVICES_U,
.rst_set_reg = RST_DEVICES_SET_U,
.rst_clr_reg = RST_DEVICES_CLR_U,
},
[3] = {
.enb_reg = CLK_OUT_ENB_V,
.enb_set_reg = CLK_OUT_ENB_SET_V,
.enb_clr_reg = CLK_OUT_ENB_CLR_V,
.rst_reg = RST_DEVICES_V,
.rst_set_reg = RST_DEVICES_SET_V,
.rst_clr_reg = RST_DEVICES_CLR_V,
},
[4] = {
.enb_reg = CLK_OUT_ENB_W,
.enb_set_reg = CLK_OUT_ENB_SET_W,
.enb_clr_reg = CLK_OUT_ENB_CLR_W,
.rst_reg = RST_DEVICES_W,
.rst_set_reg = RST_DEVICES_SET_W,
.rst_clr_reg = RST_DEVICES_CLR_W,
},
[5] = {
.enb_reg = CLK_OUT_ENB_X,
.enb_set_reg = CLK_OUT_ENB_SET_X,
.enb_clr_reg = CLK_OUT_ENB_CLR_X,
.rst_reg = RST_DEVICES_X,
.rst_set_reg = RST_DEVICES_SET_X,
.rst_clr_reg = RST_DEVICES_CLR_X,
},
[6] = {
.enb_reg = CLK_OUT_ENB_Y,
.enb_set_reg = CLK_OUT_ENB_SET_Y,
.enb_clr_reg = CLK_OUT_ENB_CLR_Y,
.rst_reg = RST_DEVICES_Y,
.rst_set_reg = RST_DEVICES_SET_Y,
.rst_clr_reg = RST_DEVICES_CLR_Y,
},
};
static void __iomem *clk_base;
static int tegra_clk_rst_assert(struct reset_controller_dev *rcdev,
unsigned long id)
{
/*
* If peripheral is on the APB bus then we must read the APB bus to
* flush the write operation in apb bus. This will avoid peripheral
* access after disabling clock. Since the reset driver has no
* knowledge of which reset IDs represent which devices, simply do
* this all the time.
*/
tegra_read_chipid();
if (id < periph_banks * 32) {
writel_relaxed(BIT(id % 32),
clk_base + periph_regs[id / 32].rst_set_reg);
return 0;
} else if (id < periph_banks * 32 + num_special_reset) {
return special_reset_assert(id);
}
return -EINVAL;
}
static int tegra_clk_rst_deassert(struct reset_controller_dev *rcdev,
unsigned long id)
{
if (id < periph_banks * 32) {
writel_relaxed(BIT(id % 32),
clk_base + periph_regs[id / 32].rst_clr_reg);
return 0;
} else if (id < periph_banks * 32 + num_special_reset) {
return special_reset_deassert(id);
}
return -EINVAL;
}
static int tegra_clk_rst_reset(struct reset_controller_dev *rcdev,
unsigned long id)
{
int err;
err = tegra_clk_rst_assert(rcdev, id);
if (err)
return err;
udelay(1);
return tegra_clk_rst_deassert(rcdev, id);
}
const struct tegra_clk_periph_regs *get_reg_bank(int clkid)
{
int reg_bank = clkid / 32;
if (reg_bank < periph_banks)
return &periph_regs[reg_bank];
else {
WARN_ON(1);
return NULL;
}
}
struct clk ** __init tegra_clk_init(void __iomem *regs, int num, int banks)
{
clk_base = regs;
if (WARN_ON(banks > ARRAY_SIZE(periph_regs)))
return NULL;
periph_clk_enb_refcnt = kzalloc(32 * banks *
sizeof(*periph_clk_enb_refcnt), GFP_KERNEL);
if (!periph_clk_enb_refcnt)
return NULL;
periph_banks = banks;
clks = kzalloc(num * sizeof(struct clk *), GFP_KERNEL);
if (!clks)
kfree(periph_clk_enb_refcnt);
clk_num = num;
return clks;
}
void __init tegra_init_dup_clks(struct tegra_clk_duplicate *dup_list,
struct clk *clks[], int clk_max)
{
struct clk *clk;
for (; dup_list->clk_id < clk_max; dup_list++) {
clk = clks[dup_list->clk_id];
dup_list->lookup.clk = clk;
clkdev_add(&dup_list->lookup);
}
}
void __init tegra_init_from_table(struct tegra_clk_init_table *tbl,
struct clk *clks[], int clk_max)
{
struct clk *clk;
for (; tbl->clk_id < clk_max; tbl++) {
clk = clks[tbl->clk_id];
if (IS_ERR_OR_NULL(clk)) {
pr_err("%s: invalid entry %ld in clks array for id %d\n",
__func__, PTR_ERR(clk), tbl->clk_id);
WARN_ON(1);
continue;
}
if (tbl->parent_id < clk_max) {
struct clk *parent = clks[tbl->parent_id];
if (clk_set_parent(clk, parent)) {
pr_err("%s: Failed to set parent %s of %s\n",
__func__, __clk_get_name(parent),
__clk_get_name(clk));
WARN_ON(1);
}
}
if (tbl->rate)
if (clk_set_rate(clk, tbl->rate)) {
pr_err("%s: Failed to set rate %lu of %s\n",
__func__, tbl->rate,
__clk_get_name(clk));
WARN_ON(1);
}
if (tbl->state)
if (clk_prepare_enable(clk)) {
pr_err("%s: Failed to enable %s\n", __func__,
__clk_get_name(clk));
WARN_ON(1);
}
}
}
static const struct reset_control_ops rst_ops = {
.assert = tegra_clk_rst_assert,
.deassert = tegra_clk_rst_deassert,
.reset = tegra_clk_rst_reset,
};
static struct reset_controller_dev rst_ctlr = {
.ops = &rst_ops,
.owner = THIS_MODULE,
.of_reset_n_cells = 1,
};
void __init tegra_add_of_provider(struct device_node *np)
{
int i;
for (i = 0; i < clk_num; i++) {
if (IS_ERR(clks[i])) {
pr_err
("Tegra clk %d: register failed with %ld\n",
i, PTR_ERR(clks[i]));
}
if (!clks[i])
clks[i] = ERR_PTR(-EINVAL);
}
clk_data.clks = clks;
clk_data.clk_num = clk_num;
of_clk_add_provider(np, of_clk_src_onecell_get, &clk_data);
rst_ctlr.of_node = np;
rst_ctlr.nr_resets = periph_banks * 32 + num_special_reset;
reset_controller_register(&rst_ctlr);
}
void __init tegra_init_special_resets(unsigned int num,
int (*assert)(unsigned long),
int (*deassert)(unsigned long))
{
num_special_reset = num;
special_reset_assert = assert;
special_reset_deassert = deassert;
}
void __init tegra_register_devclks(struct tegra_devclk *dev_clks, int num)
{
int i;
for (i = 0; i < num; i++, dev_clks++)
clk_register_clkdev(clks[dev_clks->dt_id], dev_clks->con_id,
dev_clks->dev_id);
for (i = 0; i < clk_num; i++) {
if (!IS_ERR_OR_NULL(clks[i]))
clk_register_clkdev(clks[i], __clk_get_name(clks[i]),
"tegra-clk-debug");
}
}
struct clk ** __init tegra_lookup_dt_id(int clk_id,
struct tegra_clk *tegra_clk)
{
if (tegra_clk[clk_id].present)
return &clks[tegra_clk[clk_id].dt_id];
else
return NULL;
}
tegra_clk_apply_init_table_func tegra_clk_apply_init_table;
static int __init tegra_clocks_apply_init_table(void)
{
if (!tegra_clk_apply_init_table)
return 0;
tegra_clk_apply_init_table();
return 0;
}
arch_initcall(tegra_clocks_apply_init_table);