linux/drivers/clk/socfpga/clk-gate.c
Dinh Nguyen 0691bb1b5a clk: socfpga: add divider registers to the main pll outputs
The C0(mpu_clk), C1(main_clk), and C2(dbg_base_clk) outputs from the main
PLL go through a pre-divider before coming into the system. These registers
were hidden for the CycloneV platform, but are now used for the ArriaV
platform.

This patch updates the clock driver to read the div-reg property for the
socfpga-periph-clk clocks. Also moves the div_mask define to clk.h for re-use.

Signed-off-by: Dinh Nguyen <dinguyen@altera.com>
2014-05-12 12:27:22 -05:00

263 lines
6.7 KiB
C

/*
* Copyright 2011-2012 Calxeda, Inc.
* Copyright (C) 2012-2013 Altera Corporation <www.altera.com>
*
* 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; either version 2 of the License, or
* (at your option) any later version.
*
* 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.
*
* Based from clk-highbank.c
*
*/
#include <linux/clk.h>
#include <linux/clkdev.h>
#include <linux/clk-provider.h>
#include <linux/io.h>
#include <linux/mfd/syscon.h>
#include <linux/of.h>
#include <linux/regmap.h>
#include "clk.h"
#define SOCFPGA_L4_MP_CLK "l4_mp_clk"
#define SOCFPGA_L4_SP_CLK "l4_sp_clk"
#define SOCFPGA_NAND_CLK "nand_clk"
#define SOCFPGA_NAND_X_CLK "nand_x_clk"
#define SOCFPGA_MMC_CLK "sdmmc_clk"
#define SOCFPGA_GPIO_DB_CLK_OFFSET 0xA8
#define streq(a, b) (strcmp((a), (b)) == 0)
#define to_socfpga_gate_clk(p) container_of(p, struct socfpga_gate_clk, hw.hw)
/* SDMMC Group for System Manager defines */
#define SYSMGR_SDMMCGRP_CTRL_OFFSET 0x108
#define SYSMGR_SDMMC_CTRL_SET(smplsel, drvsel) \
((((smplsel) & 0x7) << 3) | (((drvsel) & 0x7) << 0))
static u8 socfpga_clk_get_parent(struct clk_hw *hwclk)
{
u32 l4_src;
u32 perpll_src;
if (streq(hwclk->init->name, SOCFPGA_L4_MP_CLK)) {
l4_src = readl(clk_mgr_base_addr + CLKMGR_L4SRC);
return l4_src &= 0x1;
}
if (streq(hwclk->init->name, SOCFPGA_L4_SP_CLK)) {
l4_src = readl(clk_mgr_base_addr + CLKMGR_L4SRC);
return !!(l4_src & 2);
}
perpll_src = readl(clk_mgr_base_addr + CLKMGR_PERPLL_SRC);
if (streq(hwclk->init->name, SOCFPGA_MMC_CLK))
return perpll_src &= 0x3;
if (streq(hwclk->init->name, SOCFPGA_NAND_CLK) ||
streq(hwclk->init->name, SOCFPGA_NAND_X_CLK))
return (perpll_src >> 2) & 3;
/* QSPI clock */
return (perpll_src >> 4) & 3;
}
static int socfpga_clk_set_parent(struct clk_hw *hwclk, u8 parent)
{
u32 src_reg;
if (streq(hwclk->init->name, SOCFPGA_L4_MP_CLK)) {
src_reg = readl(clk_mgr_base_addr + CLKMGR_L4SRC);
src_reg &= ~0x1;
src_reg |= parent;
writel(src_reg, clk_mgr_base_addr + CLKMGR_L4SRC);
} else if (streq(hwclk->init->name, SOCFPGA_L4_SP_CLK)) {
src_reg = readl(clk_mgr_base_addr + CLKMGR_L4SRC);
src_reg &= ~0x2;
src_reg |= (parent << 1);
writel(src_reg, clk_mgr_base_addr + CLKMGR_L4SRC);
} else {
src_reg = readl(clk_mgr_base_addr + CLKMGR_PERPLL_SRC);
if (streq(hwclk->init->name, SOCFPGA_MMC_CLK)) {
src_reg &= ~0x3;
src_reg |= parent;
} else if (streq(hwclk->init->name, SOCFPGA_NAND_CLK) ||
streq(hwclk->init->name, SOCFPGA_NAND_X_CLK)) {
src_reg &= ~0xC;
src_reg |= (parent << 2);
} else {/* QSPI clock */
src_reg &= ~0x30;
src_reg |= (parent << 4);
}
writel(src_reg, clk_mgr_base_addr + CLKMGR_PERPLL_SRC);
}
return 0;
}
static unsigned long socfpga_clk_recalc_rate(struct clk_hw *hwclk,
unsigned long parent_rate)
{
struct socfpga_gate_clk *socfpgaclk = to_socfpga_gate_clk(hwclk);
u32 div = 1, val;
if (socfpgaclk->fixed_div)
div = socfpgaclk->fixed_div;
else if (socfpgaclk->div_reg) {
val = readl(socfpgaclk->div_reg) >> socfpgaclk->shift;
val &= div_mask(socfpgaclk->width);
/* Check for GPIO_DB_CLK by its offset */
if ((int) socfpgaclk->div_reg & SOCFPGA_GPIO_DB_CLK_OFFSET)
div = val + 1;
else
div = (1 << val);
}
return parent_rate / div;
}
static int socfpga_clk_prepare(struct clk_hw *hwclk)
{
struct socfpga_gate_clk *socfpgaclk = to_socfpga_gate_clk(hwclk);
struct regmap *sys_mgr_base_addr;
int i;
u32 hs_timing;
u32 clk_phase[2];
if (socfpgaclk->clk_phase[0] || socfpgaclk->clk_phase[1]) {
sys_mgr_base_addr = syscon_regmap_lookup_by_compatible("altr,sys-mgr");
if (IS_ERR(sys_mgr_base_addr)) {
pr_err("%s: failed to find altr,sys-mgr regmap!\n", __func__);
return -EINVAL;
}
for (i = 0; i < 2; i++) {
switch (socfpgaclk->clk_phase[i]) {
case 0:
clk_phase[i] = 0;
break;
case 45:
clk_phase[i] = 1;
break;
case 90:
clk_phase[i] = 2;
break;
case 135:
clk_phase[i] = 3;
break;
case 180:
clk_phase[i] = 4;
break;
case 225:
clk_phase[i] = 5;
break;
case 270:
clk_phase[i] = 6;
break;
case 315:
clk_phase[i] = 7;
break;
default:
clk_phase[i] = 0;
break;
}
}
hs_timing = SYSMGR_SDMMC_CTRL_SET(clk_phase[0], clk_phase[1]);
regmap_write(sys_mgr_base_addr, SYSMGR_SDMMCGRP_CTRL_OFFSET,
hs_timing);
}
return 0;
}
static struct clk_ops gateclk_ops = {
.prepare = socfpga_clk_prepare,
.recalc_rate = socfpga_clk_recalc_rate,
.get_parent = socfpga_clk_get_parent,
.set_parent = socfpga_clk_set_parent,
};
static void __init __socfpga_gate_init(struct device_node *node,
const struct clk_ops *ops)
{
u32 clk_gate[2];
u32 div_reg[3];
u32 clk_phase[2];
u32 fixed_div;
struct clk *clk;
struct socfpga_gate_clk *socfpga_clk;
const char *clk_name = node->name;
const char *parent_name[SOCFPGA_MAX_PARENTS];
struct clk_init_data init;
int rc;
int i = 0;
socfpga_clk = kzalloc(sizeof(*socfpga_clk), GFP_KERNEL);
if (WARN_ON(!socfpga_clk))
return;
rc = of_property_read_u32_array(node, "clk-gate", clk_gate, 2);
if (rc)
clk_gate[0] = 0;
if (clk_gate[0]) {
socfpga_clk->hw.reg = clk_mgr_base_addr + clk_gate[0];
socfpga_clk->hw.bit_idx = clk_gate[1];
gateclk_ops.enable = clk_gate_ops.enable;
gateclk_ops.disable = clk_gate_ops.disable;
}
rc = of_property_read_u32(node, "fixed-divider", &fixed_div);
if (rc)
socfpga_clk->fixed_div = 0;
else
socfpga_clk->fixed_div = fixed_div;
rc = of_property_read_u32_array(node, "div-reg", div_reg, 3);
if (!rc) {
socfpga_clk->div_reg = clk_mgr_base_addr + div_reg[0];
socfpga_clk->shift = div_reg[1];
socfpga_clk->width = div_reg[2];
} else {
socfpga_clk->div_reg = 0;
}
rc = of_property_read_u32_array(node, "clk-phase", clk_phase, 2);
if (!rc) {
socfpga_clk->clk_phase[0] = clk_phase[0];
socfpga_clk->clk_phase[1] = clk_phase[1];
}
of_property_read_string(node, "clock-output-names", &clk_name);
init.name = clk_name;
init.ops = ops;
init.flags = 0;
while (i < SOCFPGA_MAX_PARENTS && (parent_name[i] =
of_clk_get_parent_name(node, i)) != NULL)
i++;
init.parent_names = parent_name;
init.num_parents = i;
socfpga_clk->hw.hw.init = &init;
clk = clk_register(NULL, &socfpga_clk->hw.hw);
if (WARN_ON(IS_ERR(clk))) {
kfree(socfpga_clk);
return;
}
rc = of_clk_add_provider(node, of_clk_src_simple_get, clk);
if (WARN_ON(rc))
return;
}
void __init socfpga_gate_init(struct device_node *node)
{
__socfpga_gate_init(node, &gateclk_ops);
}