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/*
* AXI clkgen driver
*
* Copyright 2012-2013 Analog Devices Inc.
* Author: Lars-Peter Clausen <lars@metafoo.de>
*
* Licensed under the GPL-2.
*
*/
#include <linux/platform_device.h>
#include <linux/clk-provider.h>
#include <linux/clk.h>
#include <linux/slab.h>
#include <linux/io.h>
#include <linux/of.h>
#include <linux/module.h>
#include <linux/err.h>
#define AXI_CLKGEN_V1_REG_UPDATE_ENABLE 0x04
#define AXI_CLKGEN_V1_REG_CLK_OUT1 0x08
#define AXI_CLKGEN_V1_REG_CLK_OUT2 0x0c
#define AXI_CLKGEN_V1_REG_CLK_DIV 0x10
#define AXI_CLKGEN_V1_REG_CLK_FB1 0x14
#define AXI_CLKGEN_V1_REG_CLK_FB2 0x18
#define AXI_CLKGEN_V1_REG_LOCK1 0x1c
#define AXI_CLKGEN_V1_REG_LOCK2 0x20
#define AXI_CLKGEN_V1_REG_LOCK3 0x24
#define AXI_CLKGEN_V1_REG_FILTER1 0x28
#define AXI_CLKGEN_V1_REG_FILTER2 0x2c
#define AXI_CLKGEN_V2_REG_RESET 0x40
#define AXI_CLKGEN_V2_REG_DRP_CNTRL 0x70
#define AXI_CLKGEN_V2_REG_DRP_STATUS 0x74
#define AXI_CLKGEN_V2_RESET_MMCM_ENABLE BIT(1)
#define AXI_CLKGEN_V2_RESET_ENABLE BIT(0)
#define AXI_CLKGEN_V2_DRP_CNTRL_SEL BIT(29)
#define AXI_CLKGEN_V2_DRP_CNTRL_READ BIT(28)
#define AXI_CLKGEN_V2_DRP_STATUS_BUSY BIT(16)
#define MMCM_REG_CLKOUT0_1 0x08
#define MMCM_REG_CLKOUT0_2 0x09
#define MMCM_REG_CLK_FB1 0x14
#define MMCM_REG_CLK_FB2 0x15
#define MMCM_REG_CLK_DIV 0x16
#define MMCM_REG_LOCK1 0x18
#define MMCM_REG_LOCK2 0x19
#define MMCM_REG_LOCK3 0x1a
#define MMCM_REG_FILTER1 0x4e
#define MMCM_REG_FILTER2 0x4f
struct axi_clkgen;
struct axi_clkgen_mmcm_ops {
void (*enable)(struct axi_clkgen *axi_clkgen, bool enable);
int (*write)(struct axi_clkgen *axi_clkgen, unsigned int reg,
unsigned int val, unsigned int mask);
int (*read)(struct axi_clkgen *axi_clkgen, unsigned int reg,
unsigned int *val);
};
struct axi_clkgen {
void __iomem *base;
const struct axi_clkgen_mmcm_ops *mmcm_ops;
struct clk_hw clk_hw;
};
static void axi_clkgen_mmcm_enable(struct axi_clkgen *axi_clkgen,
bool enable)
{
axi_clkgen->mmcm_ops->enable(axi_clkgen, enable);
}
static int axi_clkgen_mmcm_write(struct axi_clkgen *axi_clkgen,
unsigned int reg, unsigned int val, unsigned int mask)
{
return axi_clkgen->mmcm_ops->write(axi_clkgen, reg, val, mask);
}
static int axi_clkgen_mmcm_read(struct axi_clkgen *axi_clkgen,
unsigned int reg, unsigned int *val)
{
return axi_clkgen->mmcm_ops->read(axi_clkgen, reg, val);
}
static uint32_t axi_clkgen_lookup_filter(unsigned int m)
{
switch (m) {
case 0:
return 0x01001990;
case 1:
return 0x01001190;
case 2:
return 0x01009890;
case 3:
return 0x01001890;
case 4:
return 0x01008890;
case 5 ... 8:
return 0x01009090;
case 9 ... 11:
return 0x01000890;
case 12:
return 0x08009090;
case 13 ... 22:
return 0x01001090;
case 23 ... 36:
return 0x01008090;
case 37 ... 46:
return 0x08001090;
default:
return 0x08008090;
}
}
static const uint32_t axi_clkgen_lock_table[] = {
0x060603e8, 0x060603e8, 0x080803e8, 0x0b0b03e8,
0x0e0e03e8, 0x111103e8, 0x131303e8, 0x161603e8,
0x191903e8, 0x1c1c03e8, 0x1f1f0384, 0x1f1f0339,
0x1f1f02ee, 0x1f1f02bc, 0x1f1f028a, 0x1f1f0271,
0x1f1f023f, 0x1f1f0226, 0x1f1f020d, 0x1f1f01f4,
0x1f1f01db, 0x1f1f01c2, 0x1f1f01a9, 0x1f1f0190,
0x1f1f0190, 0x1f1f0177, 0x1f1f015e, 0x1f1f015e,
0x1f1f0145, 0x1f1f0145, 0x1f1f012c, 0x1f1f012c,
0x1f1f012c, 0x1f1f0113, 0x1f1f0113, 0x1f1f0113,
};
static uint32_t axi_clkgen_lookup_lock(unsigned int m)
{
if (m < ARRAY_SIZE(axi_clkgen_lock_table))
return axi_clkgen_lock_table[m];
return 0x1f1f00fa;
}
static const unsigned int fpfd_min = 10000;
static const unsigned int fpfd_max = 300000;
static const unsigned int fvco_min = 600000;
static const unsigned int fvco_max = 1200000;
static void axi_clkgen_calc_params(unsigned long fin, unsigned long fout,
unsigned int *best_d, unsigned int *best_m, unsigned int *best_dout)
{
unsigned long d, d_min, d_max, _d_min, _d_max;
unsigned long m, m_min, m_max;
unsigned long f, dout, best_f, fvco;
fin /= 1000;
fout /= 1000;
best_f = ULONG_MAX;
*best_d = 0;
*best_m = 0;
*best_dout = 0;
d_min = max_t(unsigned long, DIV_ROUND_UP(fin, fpfd_max), 1);
d_max = min_t(unsigned long, fin / fpfd_min, 80);
m_min = max_t(unsigned long, DIV_ROUND_UP(fvco_min, fin) * d_min, 1);
m_max = min_t(unsigned long, fvco_max * d_max / fin, 64);
for (m = m_min; m <= m_max; m++) {
_d_min = max(d_min, DIV_ROUND_UP(fin * m, fvco_max));
_d_max = min(d_max, fin * m / fvco_min);
for (d = _d_min; d <= _d_max; d++) {
fvco = fin * m / d;
dout = DIV_ROUND_CLOSEST(fvco, fout);
dout = clamp_t(unsigned long, dout, 1, 128);
f = fvco / dout;
if (abs(f - fout) < abs(best_f - fout)) {
best_f = f;
*best_d = d;
*best_m = m;
*best_dout = dout;
if (best_f == fout)
return;
}
}
}
}
static void axi_clkgen_calc_clk_params(unsigned int divider, unsigned int *low,
unsigned int *high, unsigned int *edge, unsigned int *nocount)
{
if (divider == 1)
*nocount = 1;
else
*nocount = 0;
*high = divider / 2;
*edge = divider % 2;
*low = divider - *high;
}
static void axi_clkgen_write(struct axi_clkgen *axi_clkgen,
unsigned int reg, unsigned int val)
{
writel(val, axi_clkgen->base + reg);
}
static void axi_clkgen_read(struct axi_clkgen *axi_clkgen,
unsigned int reg, unsigned int *val)
{
*val = readl(axi_clkgen->base + reg);
}
static unsigned int axi_clkgen_v1_map_mmcm_reg(unsigned int reg)
{
switch (reg) {
case MMCM_REG_CLKOUT0_1:
return AXI_CLKGEN_V1_REG_CLK_OUT1;
case MMCM_REG_CLKOUT0_2:
return AXI_CLKGEN_V1_REG_CLK_OUT2;
case MMCM_REG_CLK_FB1:
return AXI_CLKGEN_V1_REG_CLK_FB1;
case MMCM_REG_CLK_FB2:
return AXI_CLKGEN_V1_REG_CLK_FB2;
case MMCM_REG_CLK_DIV:
return AXI_CLKGEN_V1_REG_CLK_DIV;
case MMCM_REG_LOCK1:
return AXI_CLKGEN_V1_REG_LOCK1;
case MMCM_REG_LOCK2:
return AXI_CLKGEN_V1_REG_LOCK2;
case MMCM_REG_LOCK3:
return AXI_CLKGEN_V1_REG_LOCK3;
case MMCM_REG_FILTER1:
return AXI_CLKGEN_V1_REG_FILTER1;
case MMCM_REG_FILTER2:
return AXI_CLKGEN_V1_REG_FILTER2;
default:
return 0;
}
}
static int axi_clkgen_v1_mmcm_write(struct axi_clkgen *axi_clkgen,
unsigned int reg, unsigned int val, unsigned int mask)
{
reg = axi_clkgen_v1_map_mmcm_reg(reg);
if (reg == 0)
return -EINVAL;
axi_clkgen_write(axi_clkgen, reg, val);
return 0;
}
static int axi_clkgen_v1_mmcm_read(struct axi_clkgen *axi_clkgen,
unsigned int reg, unsigned int *val)
{
reg = axi_clkgen_v1_map_mmcm_reg(reg);
if (reg == 0)
return -EINVAL;
axi_clkgen_read(axi_clkgen, reg, val);
return 0;
}
static void axi_clkgen_v1_mmcm_enable(struct axi_clkgen *axi_clkgen,
bool enable)
{
axi_clkgen_write(axi_clkgen, AXI_CLKGEN_V1_REG_UPDATE_ENABLE, enable);
}
static const struct axi_clkgen_mmcm_ops axi_clkgen_v1_mmcm_ops = {
.write = axi_clkgen_v1_mmcm_write,
.read = axi_clkgen_v1_mmcm_read,
.enable = axi_clkgen_v1_mmcm_enable,
};
static int axi_clkgen_wait_non_busy(struct axi_clkgen *axi_clkgen)
{
unsigned int timeout = 10000;
unsigned int val;
do {
axi_clkgen_read(axi_clkgen, AXI_CLKGEN_V2_REG_DRP_STATUS, &val);
} while ((val & AXI_CLKGEN_V2_DRP_STATUS_BUSY) && --timeout);
if (val & AXI_CLKGEN_V2_DRP_STATUS_BUSY)
return -EIO;
return val & 0xffff;
}
static int axi_clkgen_v2_mmcm_read(struct axi_clkgen *axi_clkgen,
unsigned int reg, unsigned int *val)
{
unsigned int reg_val;
int ret;
ret = axi_clkgen_wait_non_busy(axi_clkgen);
if (ret < 0)
return ret;
reg_val = AXI_CLKGEN_V2_DRP_CNTRL_SEL | AXI_CLKGEN_V2_DRP_CNTRL_READ;
reg_val |= (reg << 16);
axi_clkgen_write(axi_clkgen, AXI_CLKGEN_V2_REG_DRP_CNTRL, reg_val);
ret = axi_clkgen_wait_non_busy(axi_clkgen);
if (ret < 0)
return ret;
*val = ret;
return 0;
}
static int axi_clkgen_v2_mmcm_write(struct axi_clkgen *axi_clkgen,
unsigned int reg, unsigned int val, unsigned int mask)
{
unsigned int reg_val = 0;
int ret;
ret = axi_clkgen_wait_non_busy(axi_clkgen);
if (ret < 0)
return ret;
if (mask != 0xffff) {
axi_clkgen_v2_mmcm_read(axi_clkgen, reg, &reg_val);
reg_val &= ~mask;
}
reg_val |= AXI_CLKGEN_V2_DRP_CNTRL_SEL | (reg << 16) | (val & mask);
axi_clkgen_write(axi_clkgen, AXI_CLKGEN_V2_REG_DRP_CNTRL, reg_val);
return 0;
}
static void axi_clkgen_v2_mmcm_enable(struct axi_clkgen *axi_clkgen,
bool enable)
{
unsigned int val = AXI_CLKGEN_V2_RESET_ENABLE;
if (enable)
val |= AXI_CLKGEN_V2_RESET_MMCM_ENABLE;
axi_clkgen_write(axi_clkgen, AXI_CLKGEN_V2_REG_RESET, val);
}
static const struct axi_clkgen_mmcm_ops axi_clkgen_v2_mmcm_ops = {
.write = axi_clkgen_v2_mmcm_write,
.read = axi_clkgen_v2_mmcm_read,
.enable = axi_clkgen_v2_mmcm_enable,
};
static struct axi_clkgen *clk_hw_to_axi_clkgen(struct clk_hw *clk_hw)
{
return container_of(clk_hw, struct axi_clkgen, clk_hw);
}
static int axi_clkgen_set_rate(struct clk_hw *clk_hw,
unsigned long rate, unsigned long parent_rate)
{
struct axi_clkgen *axi_clkgen = clk_hw_to_axi_clkgen(clk_hw);
unsigned int d, m, dout;
unsigned int nocount;
unsigned int high;
unsigned int edge;
unsigned int low;
uint32_t filter;
uint32_t lock;
if (parent_rate == 0 || rate == 0)
return -EINVAL;
axi_clkgen_calc_params(parent_rate, rate, &d, &m, &dout);
if (d == 0 || dout == 0 || m == 0)
return -EINVAL;
filter = axi_clkgen_lookup_filter(m - 1);
lock = axi_clkgen_lookup_lock(m - 1);
axi_clkgen_calc_clk_params(dout, &low, &high, &edge, &nocount);
axi_clkgen_mmcm_write(axi_clkgen, MMCM_REG_CLKOUT0_1,
(high << 6) | low, 0xefff);
axi_clkgen_mmcm_write(axi_clkgen, MMCM_REG_CLKOUT0_2,
(edge << 7) | (nocount << 6), 0x03ff);
axi_clkgen_calc_clk_params(d, &low, &high, &edge, &nocount);
axi_clkgen_mmcm_write(axi_clkgen, MMCM_REG_CLK_DIV,
(edge << 13) | (nocount << 12) | (high << 6) | low, 0x3fff);
axi_clkgen_calc_clk_params(m, &low, &high, &edge, &nocount);
axi_clkgen_mmcm_write(axi_clkgen, MMCM_REG_CLK_FB1,
(high << 6) | low, 0xefff);
axi_clkgen_mmcm_write(axi_clkgen, MMCM_REG_CLK_FB2,
(edge << 7) | (nocount << 6), 0x03ff);
axi_clkgen_mmcm_write(axi_clkgen, MMCM_REG_LOCK1, lock & 0x3ff, 0x3ff);
axi_clkgen_mmcm_write(axi_clkgen, MMCM_REG_LOCK2,
(((lock >> 16) & 0x1f) << 10) | 0x1, 0x7fff);
axi_clkgen_mmcm_write(axi_clkgen, MMCM_REG_LOCK3,
(((lock >> 24) & 0x1f) << 10) | 0x3e9, 0x7fff);
axi_clkgen_mmcm_write(axi_clkgen, MMCM_REG_FILTER1, filter >> 16, 0x9900);
axi_clkgen_mmcm_write(axi_clkgen, MMCM_REG_FILTER2, filter, 0x9900);
return 0;
}
static long axi_clkgen_round_rate(struct clk_hw *hw, unsigned long rate,
unsigned long *parent_rate)
{
unsigned int d, m, dout;
axi_clkgen_calc_params(*parent_rate, rate, &d, &m, &dout);
if (d == 0 || dout == 0 || m == 0)
return -EINVAL;
return *parent_rate / d * m / dout;
}
static unsigned long axi_clkgen_recalc_rate(struct clk_hw *clk_hw,
unsigned long parent_rate)
{
struct axi_clkgen *axi_clkgen = clk_hw_to_axi_clkgen(clk_hw);
unsigned int d, m, dout;
unsigned int reg;
unsigned long long tmp;
axi_clkgen_mmcm_read(axi_clkgen, MMCM_REG_CLKOUT0_1, &reg);
dout = (reg & 0x3f) + ((reg >> 6) & 0x3f);
axi_clkgen_mmcm_read(axi_clkgen, MMCM_REG_CLK_DIV, &reg);
d = (reg & 0x3f) + ((reg >> 6) & 0x3f);
axi_clkgen_mmcm_read(axi_clkgen, MMCM_REG_CLK_FB1, &reg);
m = (reg & 0x3f) + ((reg >> 6) & 0x3f);
if (d == 0 || dout == 0)
return 0;
tmp = (unsigned long long)(parent_rate / d) * m;
do_div(tmp, dout);
if (tmp > ULONG_MAX)
return ULONG_MAX;
return tmp;
}
static int axi_clkgen_enable(struct clk_hw *clk_hw)
{
struct axi_clkgen *axi_clkgen = clk_hw_to_axi_clkgen(clk_hw);
axi_clkgen_mmcm_enable(axi_clkgen, true);
return 0;
}
static void axi_clkgen_disable(struct clk_hw *clk_hw)
{
struct axi_clkgen *axi_clkgen = clk_hw_to_axi_clkgen(clk_hw);
axi_clkgen_mmcm_enable(axi_clkgen, false);
}
static const struct clk_ops axi_clkgen_ops = {
.recalc_rate = axi_clkgen_recalc_rate,
.round_rate = axi_clkgen_round_rate,
.set_rate = axi_clkgen_set_rate,
.enable = axi_clkgen_enable,
.disable = axi_clkgen_disable,
};
static const struct of_device_id axi_clkgen_ids[] = {
{
.compatible = "adi,axi-clkgen-1.00.a",
.data = &axi_clkgen_v1_mmcm_ops
}, {
.compatible = "adi,axi-clkgen-2.00.a",
.data = &axi_clkgen_v2_mmcm_ops,
},
{ },
};
MODULE_DEVICE_TABLE(of, axi_clkgen_ids);
static int axi_clkgen_probe(struct platform_device *pdev)
{
const struct of_device_id *id;
struct axi_clkgen *axi_clkgen;
struct clk_init_data init;
const char *parent_name;
const char *clk_name;
struct resource *mem;
struct clk *clk;
if (!pdev->dev.of_node)
return -ENODEV;
id = of_match_node(axi_clkgen_ids, pdev->dev.of_node);
if (!id)
return -ENODEV;
axi_clkgen = devm_kzalloc(&pdev->dev, sizeof(*axi_clkgen), GFP_KERNEL);
if (!axi_clkgen)
return -ENOMEM;
axi_clkgen->mmcm_ops = id->data;
mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
axi_clkgen->base = devm_ioremap_resource(&pdev->dev, mem);
if (IS_ERR(axi_clkgen->base))
return PTR_ERR(axi_clkgen->base);
parent_name = of_clk_get_parent_name(pdev->dev.of_node, 0);
if (!parent_name)
return -EINVAL;
clk_name = pdev->dev.of_node->name;
of_property_read_string(pdev->dev.of_node, "clock-output-names",
&clk_name);
init.name = clk_name;
init.ops = &axi_clkgen_ops;
init.flags = CLK_SET_RATE_GATE;
init.parent_names = &parent_name;
init.num_parents = 1;
axi_clkgen_mmcm_enable(axi_clkgen, false);
axi_clkgen->clk_hw.init = &init;
clk = devm_clk_register(&pdev->dev, &axi_clkgen->clk_hw);
if (IS_ERR(clk))
return PTR_ERR(clk);
return of_clk_add_provider(pdev->dev.of_node, of_clk_src_simple_get,
clk);
}
static int axi_clkgen_remove(struct platform_device *pdev)
{
of_clk_del_provider(pdev->dev.of_node);
return 0;
}
static struct platform_driver axi_clkgen_driver = {
.driver = {
.name = "adi-axi-clkgen",
.of_match_table = axi_clkgen_ids,
},
.probe = axi_clkgen_probe,
.remove = axi_clkgen_remove,
};
module_platform_driver(axi_clkgen_driver);
MODULE_LICENSE("GPL v2");
MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>");
MODULE_DESCRIPTION("Driver for the Analog Devices' AXI clkgen pcore clock generator");
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