linux/drivers/clk/axis/clk-artpec6.c
Lars Persson 33b8ac917a clk: add artpec-6 clock controller
Add a driver for the main clock controller of the Artpec-6 Soc.

Signed-off-by: Lars Persson <larper@axis.com>
[sboyd@codeaurora.org: Reformatted driver structure and of match]
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2016-04-15 16:02:16 -07:00

243 lines
6.9 KiB
C

/*
* ARTPEC-6 clock initialization
*
* Copyright 2015-2016 Axis Comunications AB.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#include <linux/clk-provider.h>
#include <linux/device.h>
#include <linux/io.h>
#include <linux/of.h>
#include <linux/of_address.h>
#include <linux/platform_device.h>
#include <linux/slab.h>
#include <dt-bindings/clock/axis,artpec6-clkctrl.h>
#define NUM_I2S_CLOCKS 2
struct artpec6_clkctrl_drvdata {
struct clk *clk_table[ARTPEC6_CLK_NUMCLOCKS];
void __iomem *syscon_base;
struct clk_onecell_data clk_data;
spinlock_t i2scfg_lock;
};
static struct artpec6_clkctrl_drvdata *clkdata;
static const char *const i2s_clk_names[NUM_I2S_CLOCKS] = {
"i2s0",
"i2s1",
};
static const int i2s_clk_indexes[NUM_I2S_CLOCKS] = {
ARTPEC6_CLK_I2S0_CLK,
ARTPEC6_CLK_I2S1_CLK,
};
static void of_artpec6_clkctrl_setup(struct device_node *np)
{
int i;
const char *sys_refclk_name;
u32 pll_mode, pll_m, pll_n;
struct clk **clks;
/* Mandatory parent clock. */
i = of_property_match_string(np, "clock-names", "sys_refclk");
if (i < 0)
return;
sys_refclk_name = of_clk_get_parent_name(np, i);
clkdata = kzalloc(sizeof(*clkdata), GFP_KERNEL);
if (!clkdata)
return;
clks = clkdata->clk_table;
for (i = 0; i < ARTPEC6_CLK_NUMCLOCKS; ++i)
clks[i] = ERR_PTR(-EPROBE_DEFER);
clkdata->syscon_base = of_iomap(np, 0);
BUG_ON(clkdata->syscon_base == NULL);
/* Read PLL1 factors configured by boot strap pins. */
pll_mode = (readl(clkdata->syscon_base) >> 6) & 3;
switch (pll_mode) {
case 0: /* DDR3-2133 mode */
pll_m = 4;
pll_n = 85;
break;
case 1: /* DDR3-1866 mode */
pll_m = 6;
pll_n = 112;
break;
case 2: /* DDR3-1600 mode */
pll_m = 4;
pll_n = 64;
break;
case 3: /* DDR3-1333 mode */
pll_m = 8;
pll_n = 106;
break;
}
clks[ARTPEC6_CLK_CPU] =
clk_register_fixed_factor(NULL, "cpu", sys_refclk_name, 0, pll_n,
pll_m);
clks[ARTPEC6_CLK_CPU_PERIPH] =
clk_register_fixed_factor(NULL, "cpu_periph", "cpu", 0, 1, 2);
/* EPROBE_DEFER on the apb_clock is not handled in amba devices. */
clks[ARTPEC6_CLK_UART_PCLK] =
clk_register_fixed_factor(NULL, "uart_pclk", "cpu", 0, 1, 8);
clks[ARTPEC6_CLK_UART_REFCLK] =
clk_register_fixed_rate(NULL, "uart_ref", sys_refclk_name, 0,
50000000);
clks[ARTPEC6_CLK_SPI_PCLK] =
clk_register_fixed_factor(NULL, "spi_pclk", "cpu", 0, 1, 8);
clks[ARTPEC6_CLK_SPI_SSPCLK] =
clk_register_fixed_rate(NULL, "spi_sspclk", sys_refclk_name, 0,
50000000);
clks[ARTPEC6_CLK_DBG_PCLK] =
clk_register_fixed_factor(NULL, "dbg_pclk", "cpu", 0, 1, 8);
clkdata->clk_data.clks = clkdata->clk_table;
clkdata->clk_data.clk_num = ARTPEC6_CLK_NUMCLOCKS;
of_clk_add_provider(np, of_clk_src_onecell_get, &clkdata->clk_data);
}
CLK_OF_DECLARE(artpec6_clkctrl, "axis,artpec6-clkctrl",
of_artpec6_clkctrl_setup);
static int artpec6_clkctrl_probe(struct platform_device *pdev)
{
int propidx;
struct device_node *np = pdev->dev.of_node;
struct device *dev = &pdev->dev;
struct clk **clks = clkdata->clk_table;
const char *sys_refclk_name;
const char *i2s_refclk_name = NULL;
const char *frac_clk_name[2] = { NULL, NULL };
const char *i2s_mux_parents[2];
u32 muxreg;
int i;
int err = 0;
/* Mandatory parent clock. */
propidx = of_property_match_string(np, "clock-names", "sys_refclk");
if (propidx < 0)
return -EINVAL;
sys_refclk_name = of_clk_get_parent_name(np, propidx);
/* Find clock names of optional parent clocks. */
propidx = of_property_match_string(np, "clock-names", "i2s_refclk");
if (propidx >= 0)
i2s_refclk_name = of_clk_get_parent_name(np, propidx);
propidx = of_property_match_string(np, "clock-names", "frac_clk0");
if (propidx >= 0)
frac_clk_name[0] = of_clk_get_parent_name(np, propidx);
propidx = of_property_match_string(np, "clock-names", "frac_clk1");
if (propidx >= 0)
frac_clk_name[1] = of_clk_get_parent_name(np, propidx);
spin_lock_init(&clkdata->i2scfg_lock);
clks[ARTPEC6_CLK_NAND_CLKA] =
clk_register_fixed_factor(dev, "nand_clka", "cpu", 0, 1, 8);
clks[ARTPEC6_CLK_NAND_CLKB] =
clk_register_fixed_rate(dev, "nand_clkb", sys_refclk_name, 0,
100000000);
clks[ARTPEC6_CLK_ETH_ACLK] =
clk_register_fixed_factor(dev, "eth_aclk", "cpu", 0, 1, 4);
clks[ARTPEC6_CLK_DMA_ACLK] =
clk_register_fixed_factor(dev, "dma_aclk", "cpu", 0, 1, 4);
clks[ARTPEC6_CLK_PTP_REF] =
clk_register_fixed_rate(dev, "ptp_ref", sys_refclk_name, 0,
100000000);
clks[ARTPEC6_CLK_SD_PCLK] =
clk_register_fixed_rate(dev, "sd_pclk", sys_refclk_name, 0,
100000000);
clks[ARTPEC6_CLK_SD_IMCLK] =
clk_register_fixed_rate(dev, "sd_imclk", sys_refclk_name, 0,
100000000);
clks[ARTPEC6_CLK_I2S_HST] =
clk_register_fixed_factor(dev, "i2s_hst", "cpu", 0, 1, 8);
for (i = 0; i < NUM_I2S_CLOCKS; ++i) {
if (i2s_refclk_name && frac_clk_name[i]) {
i2s_mux_parents[0] = frac_clk_name[i];
i2s_mux_parents[1] = i2s_refclk_name;
clks[i2s_clk_indexes[i]] =
clk_register_mux(dev, i2s_clk_names[i],
i2s_mux_parents, 2,
CLK_SET_RATE_NO_REPARENT |
CLK_SET_RATE_PARENT,
clkdata->syscon_base + 0x14, i, 1,
0, &clkdata->i2scfg_lock);
} else if (frac_clk_name[i]) {
/* Lock the mux for internal clock reference. */
muxreg = readl(clkdata->syscon_base + 0x14);
muxreg &= ~BIT(i);
writel(muxreg, clkdata->syscon_base + 0x14);
clks[i2s_clk_indexes[i]] =
clk_register_fixed_factor(dev, i2s_clk_names[i],
frac_clk_name[i], 0, 1,
1);
} else if (i2s_refclk_name) {
/* Lock the mux for external clock reference. */
muxreg = readl(clkdata->syscon_base + 0x14);
muxreg |= BIT(i);
writel(muxreg, clkdata->syscon_base + 0x14);
clks[i2s_clk_indexes[i]] =
clk_register_fixed_factor(dev, i2s_clk_names[i],
i2s_refclk_name, 0, 1, 1);
}
}
clks[ARTPEC6_CLK_I2C] =
clk_register_fixed_rate(dev, "i2c", sys_refclk_name, 0, 100000000);
clks[ARTPEC6_CLK_SYS_TIMER] =
clk_register_fixed_rate(dev, "timer", sys_refclk_name, 0,
100000000);
clks[ARTPEC6_CLK_FRACDIV_IN] =
clk_register_fixed_rate(dev, "fracdiv_in", sys_refclk_name, 0,
600000000);
for (i = 0; i < ARTPEC6_CLK_NUMCLOCKS; ++i) {
if (IS_ERR(clks[i]) && PTR_ERR(clks[i]) != -EPROBE_DEFER) {
dev_err(dev,
"Failed to register clock at index %d err=%ld\n",
i, PTR_ERR(clks[i]));
err = PTR_ERR(clks[i]);
}
}
return err;
}
static const struct of_device_id artpec_clkctrl_of_match[] = {
{ .compatible = "axis,artpec6-clkctrl" },
{}
};
static struct platform_driver artpec6_clkctrl_driver = {
.probe = artpec6_clkctrl_probe,
.driver = {
.name = "artpec6_clkctrl",
.of_match_table = artpec_clkctrl_of_match,
},
};
builtin_platform_driver(artpec6_clkctrl_driver);