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path: root/drivers/clk/clk-axi-clkgen.c
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-rw-r--r--drivers/clk/clk-axi-clkgen.c569
1 files changed, 569 insertions, 0 deletions
diff --git a/drivers/clk/clk-axi-clkgen.c b/drivers/clk/clk-axi-clkgen.c
new file mode 100644
index 000000000..14d803e6a
--- /dev/null
+++ b/drivers/clk/clk-axi-clkgen.c
@@ -0,0 +1,569 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * AXI clkgen driver
+ *
+ * Copyright 2012-2013 Analog Devices Inc.
+ * Author: Lars-Peter Clausen <lars@metafoo.de>
+ */
+
+#include <linux/platform_device.h>
+#include <linux/clk-provider.h>
+#include <linux/slab.h>
+#include <linux/io.h>
+#include <linux/of.h>
+#include <linux/module.h>
+#include <linux/err.h>
+
+#define AXI_CLKGEN_V2_REG_RESET 0x40
+#define AXI_CLKGEN_V2_REG_CLKSEL 0x44
+#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_CLKOUT5_2 0x07
+#define MMCM_REG_CLKOUT0_1 0x08
+#define MMCM_REG_CLKOUT0_2 0x09
+#define MMCM_REG_CLKOUT6_2 0x13
+#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_POWER 0x28
+#define MMCM_REG_FILTER1 0x4e
+#define MMCM_REG_FILTER2 0x4f
+
+#define MMCM_CLKOUT_NOCOUNT BIT(6)
+
+#define MMCM_CLK_DIV_DIVIDE BIT(11)
+#define MMCM_CLK_DIV_NOCOUNT BIT(12)
+
+struct axi_clkgen {
+ void __iomem *base;
+ struct clk_hw clk_hw;
+};
+
+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;
+ unsigned long fract_shift = 0;
+ unsigned long fvco_min_fract, fvco_max_fract;
+
+ 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);
+
+again:
+ fvco_min_fract = fvco_min << fract_shift;
+ fvco_max_fract = fvco_max << fract_shift;
+
+ m_min = max_t(unsigned long, DIV_ROUND_UP(fvco_min_fract, fin) * d_min, 1);
+ m_max = min_t(unsigned long, fvco_max_fract * d_max / fin, 64 << fract_shift);
+
+ for (m = m_min; m <= m_max; m++) {
+ _d_min = max(d_min, DIV_ROUND_UP(fin * m, fvco_max_fract));
+ _d_max = min(d_max, fin * m / fvco_min_fract);
+
+ 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 << fract_shift);
+ f = fvco / dout;
+ if (abs(f - fout) < abs(best_f - fout)) {
+ best_f = f;
+ *best_d = d;
+ *best_m = m << (3 - fract_shift);
+ *best_dout = dout << (3 - fract_shift);
+ if (best_f == fout)
+ return;
+ }
+ }
+ }
+
+ /* Lets see if we find a better setting in fractional mode */
+ if (fract_shift == 0) {
+ fract_shift = 3;
+ goto again;
+ }
+}
+
+struct axi_clkgen_div_params {
+ unsigned int low;
+ unsigned int high;
+ unsigned int edge;
+ unsigned int nocount;
+ unsigned int frac_en;
+ unsigned int frac;
+ unsigned int frac_wf_f;
+ unsigned int frac_wf_r;
+ unsigned int frac_phase;
+};
+
+static void axi_clkgen_calc_clk_params(unsigned int divider,
+ unsigned int frac_divider, struct axi_clkgen_div_params *params)
+{
+
+ memset(params, 0x0, sizeof(*params));
+
+ if (divider == 1) {
+ params->nocount = 1;
+ return;
+ }
+
+ if (frac_divider == 0) {
+ params->high = divider / 2;
+ params->edge = divider % 2;
+ params->low = divider - params->high;
+ } else {
+ params->frac_en = 1;
+ params->frac = frac_divider;
+
+ params->high = divider / 2;
+ params->edge = divider % 2;
+ params->low = params->high;
+
+ if (params->edge == 0) {
+ params->high--;
+ params->frac_wf_r = 1;
+ }
+
+ if (params->edge == 0 || frac_divider == 1)
+ params->low--;
+ if (((params->edge == 0) ^ (frac_divider == 1)) ||
+ (divider == 2 && frac_divider == 1))
+ params->frac_wf_f = 1;
+
+ params->frac_phase = params->edge * 4 + frac_divider / 2;
+ }
+}
+
+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 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_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_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_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_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 struct axi_clkgen *clk_hw_to_axi_clkgen(struct clk_hw *clk_hw)
+{
+ return container_of(clk_hw, struct axi_clkgen, clk_hw);
+}
+
+static void axi_clkgen_set_div(struct axi_clkgen *axi_clkgen,
+ unsigned int reg1, unsigned int reg2, unsigned int reg3,
+ struct axi_clkgen_div_params *params)
+{
+ axi_clkgen_mmcm_write(axi_clkgen, reg1,
+ (params->high << 6) | params->low, 0xefff);
+ axi_clkgen_mmcm_write(axi_clkgen, reg2,
+ (params->frac << 12) | (params->frac_en << 11) |
+ (params->frac_wf_r << 10) | (params->edge << 7) |
+ (params->nocount << 6), 0x7fff);
+ if (reg3 != 0) {
+ axi_clkgen_mmcm_write(axi_clkgen, reg3,
+ (params->frac_phase << 11) | (params->frac_wf_f << 10), 0x3c00);
+ }
+}
+
+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;
+ struct axi_clkgen_div_params params;
+ uint32_t power = 0;
+ 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;
+
+ if ((dout & 0x7) != 0 || (m & 0x7) != 0)
+ power |= 0x9800;
+
+ axi_clkgen_mmcm_write(axi_clkgen, MMCM_REG_POWER, power, 0x9800);
+
+ filter = axi_clkgen_lookup_filter(m - 1);
+ lock = axi_clkgen_lookup_lock(m - 1);
+
+ axi_clkgen_calc_clk_params(dout >> 3, dout & 0x7, &params);
+ axi_clkgen_set_div(axi_clkgen, MMCM_REG_CLKOUT0_1, MMCM_REG_CLKOUT0_2,
+ MMCM_REG_CLKOUT5_2, &params);
+
+ axi_clkgen_calc_clk_params(d, 0, &params);
+ axi_clkgen_mmcm_write(axi_clkgen, MMCM_REG_CLK_DIV,
+ (params.edge << 13) | (params.nocount << 12) |
+ (params.high << 6) | params.low, 0x3fff);
+
+ axi_clkgen_calc_clk_params(m >> 3, m & 0x7, &params);
+ axi_clkgen_set_div(axi_clkgen, MMCM_REG_CLK_FB1, MMCM_REG_CLK_FB2,
+ MMCM_REG_CLKOUT6_2, &params);
+
+ 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;
+ unsigned long long tmp;
+
+ axi_clkgen_calc_params(*parent_rate, rate, &d, &m, &dout);
+
+ if (d == 0 || dout == 0 || m == 0)
+ return -EINVAL;
+
+ tmp = (unsigned long long)*parent_rate * m;
+ tmp = DIV_ROUND_CLOSEST_ULL(tmp, dout * d);
+
+ return min_t(unsigned long long, tmp, LONG_MAX);
+}
+
+static unsigned int axi_clkgen_get_div(struct axi_clkgen *axi_clkgen,
+ unsigned int reg1, unsigned int reg2)
+{
+ unsigned int val1, val2;
+ unsigned int div;
+
+ axi_clkgen_mmcm_read(axi_clkgen, reg2, &val2);
+ if (val2 & MMCM_CLKOUT_NOCOUNT)
+ return 8;
+
+ axi_clkgen_mmcm_read(axi_clkgen, reg1, &val1);
+
+ div = (val1 & 0x3f) + ((val1 >> 6) & 0x3f);
+ div <<= 3;
+
+ if (val2 & MMCM_CLK_DIV_DIVIDE) {
+ if ((val2 & BIT(7)) && (val2 & 0x7000) != 0x1000)
+ div += 8;
+ else
+ div += 16;
+
+ div += (val2 >> 12) & 0x7;
+ }
+
+ return div;
+}
+
+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 long long tmp;
+ unsigned int val;
+
+ dout = axi_clkgen_get_div(axi_clkgen, MMCM_REG_CLKOUT0_1,
+ MMCM_REG_CLKOUT0_2);
+ m = axi_clkgen_get_div(axi_clkgen, MMCM_REG_CLK_FB1,
+ MMCM_REG_CLK_FB2);
+
+ axi_clkgen_mmcm_read(axi_clkgen, MMCM_REG_CLK_DIV, &val);
+ if (val & MMCM_CLK_DIV_NOCOUNT)
+ d = 1;
+ else
+ d = (val & 0x3f) + ((val >> 6) & 0x3f);
+
+ if (d == 0 || dout == 0)
+ return 0;
+
+ tmp = (unsigned long long)parent_rate * m;
+ tmp = DIV_ROUND_CLOSEST_ULL(tmp, dout * d);
+
+ return min_t(unsigned long long, tmp, ULONG_MAX);
+}
+
+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 int axi_clkgen_set_parent(struct clk_hw *clk_hw, u8 index)
+{
+ struct axi_clkgen *axi_clkgen = clk_hw_to_axi_clkgen(clk_hw);
+
+ axi_clkgen_write(axi_clkgen, AXI_CLKGEN_V2_REG_CLKSEL, index);
+
+ return 0;
+}
+
+static u8 axi_clkgen_get_parent(struct clk_hw *clk_hw)
+{
+ struct axi_clkgen *axi_clkgen = clk_hw_to_axi_clkgen(clk_hw);
+ unsigned int parent;
+
+ axi_clkgen_read(axi_clkgen, AXI_CLKGEN_V2_REG_CLKSEL, &parent);
+
+ return parent;
+}
+
+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,
+ .set_parent = axi_clkgen_set_parent,
+ .get_parent = axi_clkgen_get_parent,
+};
+
+static const struct of_device_id axi_clkgen_ids[] = {
+ {
+ .compatible = "adi,axi-clkgen-2.00.a",
+ },
+ { },
+};
+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_names[2];
+ const char *clk_name;
+ struct resource *mem;
+ unsigned int i;
+ int ret;
+
+ 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;
+
+ 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);
+
+ init.num_parents = of_clk_get_parent_count(pdev->dev.of_node);
+ if (init.num_parents < 1 || init.num_parents > 2)
+ return -EINVAL;
+
+ for (i = 0; i < init.num_parents; i++) {
+ parent_names[i] = of_clk_get_parent_name(pdev->dev.of_node, i);
+ if (!parent_names[i])
+ 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 | CLK_SET_PARENT_GATE;
+ init.parent_names = parent_names;
+
+ axi_clkgen_mmcm_enable(axi_clkgen, false);
+
+ axi_clkgen->clk_hw.init = &init;
+ ret = devm_clk_hw_register(&pdev->dev, &axi_clkgen->clk_hw);
+ if (ret)
+ return ret;
+
+ return of_clk_add_hw_provider(pdev->dev.of_node, of_clk_hw_simple_get,
+ &axi_clkgen->clk_hw);
+}
+
+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");