drivers/clk/axis/clk-artpec6.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * ARTPEC-6 clock initialization
   4  *
   5  * Copyright 2015-2016 Axis Comunications AB.
   6  */
   7
   8 #include <linux/clk-provider.h>
   9 #include <linux/device.h>
  10 #include <linux/io.h>
  11 #include <linux/of.h>
  12 #include <linux/of_address.h>
  13 #include <linux/platform_device.h>
  14 #include <linux/slab.h>
  15 #include <dt-bindings/clock/axis,artpec6-clkctrl.h>
  16
  17 #define NUM_I2S_CLOCKS 2
  18
  19 struct artpec6_clkctrl_drvdata {
  20         struct clk *clk_table[ARTPEC6_CLK_NUMCLOCKS];
  21         void __iomem *syscon_base;
  22         struct clk_onecell_data clk_data;
  23         spinlock_t i2scfg_lock;
  24 };
  25
  26 static struct artpec6_clkctrl_drvdata *clkdata;
  27
  28 static const char *const i2s_clk_names[NUM_I2S_CLOCKS] = {
  29         "i2s0",
  30         "i2s1",
  31 };
  32
  33 static const int i2s_clk_indexes[NUM_I2S_CLOCKS] = {
  34         ARTPEC6_CLK_I2S0_CLK,
  35         ARTPEC6_CLK_I2S1_CLK,
  36 };
  37
  38 static void of_artpec6_clkctrl_setup(struct device_node *np)
  39 {
  40         int i;
  41         const char *sys_refclk_name;
  42         u32 pll_mode, pll_m, pll_n;
  43         struct clk **clks;
  44
  45         /* Mandatory parent clock. */
  46         i = of_property_match_string(np, "clock-names", "sys_refclk");
  47         if (i < 0)
  48                 return;
  49
  50         sys_refclk_name = of_clk_get_parent_name(np, i);
  51
  52         clkdata = kzalloc(sizeof(*clkdata), GFP_KERNEL);
  53         if (!clkdata)
  54                 return;
  55
  56         clks = clkdata->clk_table;
  57
  58         for (i = 0; i < ARTPEC6_CLK_NUMCLOCKS; ++i)
  59                 clks[i] = ERR_PTR(-EPROBE_DEFER);
  60
  61         clkdata->syscon_base = of_iomap(np, 0);
  62         BUG_ON(clkdata->syscon_base == NULL);
  63
  64         /* Read PLL1 factors configured by boot strap pins. */
  65         pll_mode = (readl(clkdata->syscon_base) >> 6) & 3;
  66         switch (pll_mode) {
  67         case 0:         /* DDR3-2133 mode */
  68                 pll_m = 4;
  69                 pll_n = 85;
  70                 break;
  71         case 1:         /* DDR3-1866 mode */
  72                 pll_m = 6;
  73                 pll_n = 112;
  74                 break;
  75         case 2:         /* DDR3-1600 mode */
  76                 pll_m = 4;
  77                 pll_n = 64;
  78                 break;
  79         case 3:         /* DDR3-1333 mode */
  80                 pll_m = 8;
  81                 pll_n = 106;
  82                 break;
  83         }
  84
  85         clks[ARTPEC6_CLK_CPU] =
  86             clk_register_fixed_factor(NULL, "cpu", sys_refclk_name, 0, pll_n,
  87                                       pll_m);
  88         clks[ARTPEC6_CLK_CPU_PERIPH] =
  89             clk_register_fixed_factor(NULL, "cpu_periph", "cpu", 0, 1, 2);
  90
  91         /* EPROBE_DEFER on the apb_clock is not handled in amba devices. */
  92         clks[ARTPEC6_CLK_UART_PCLK] =
  93             clk_register_fixed_factor(NULL, "uart_pclk", "cpu", 0, 1, 8);
  94         clks[ARTPEC6_CLK_UART_REFCLK] =
  95             clk_register_fixed_rate(NULL, "uart_ref", sys_refclk_name, 0,
  96                                     50000000);
  97
  98         clks[ARTPEC6_CLK_SPI_PCLK] =
  99             clk_register_fixed_factor(NULL, "spi_pclk", "cpu", 0, 1, 8);
 100         clks[ARTPEC6_CLK_SPI_SSPCLK] =
 101             clk_register_fixed_rate(NULL, "spi_sspclk", sys_refclk_name, 0,
 102                                     50000000);
 103
 104         clks[ARTPEC6_CLK_DBG_PCLK] =
 105             clk_register_fixed_factor(NULL, "dbg_pclk", "cpu", 0, 1, 8);
 106
 107         clkdata->clk_data.clks = clkdata->clk_table;
 108         clkdata->clk_data.clk_num = ARTPEC6_CLK_NUMCLOCKS;
 109
 110         of_clk_add_provider(np, of_clk_src_onecell_get, &clkdata->clk_data);
 111 }
 112
 113 CLK_OF_DECLARE_DRIVER(artpec6_clkctrl, "axis,artpec6-clkctrl",
 114                       of_artpec6_clkctrl_setup);
 115
 116 static int artpec6_clkctrl_probe(struct platform_device *pdev)
 117 {
 118         int propidx;
 119         struct device_node *np = pdev->dev.of_node;
 120         struct device *dev = &pdev->dev;
 121         struct clk **clks = clkdata->clk_table;
 122         const char *sys_refclk_name;
 123         const char *i2s_refclk_name = NULL;
 124         const char *frac_clk_name[2] = { NULL, NULL };
 125         const char *i2s_mux_parents[2];
 126         u32 muxreg;
 127         int i;
 128         int err = 0;
 129
 130         /* Mandatory parent clock. */
 131         propidx = of_property_match_string(np, "clock-names", "sys_refclk");
 132         if (propidx < 0)
 133                 return -EINVAL;
 134
 135         sys_refclk_name = of_clk_get_parent_name(np, propidx);
 136
 137         /* Find clock names of optional parent clocks. */
 138         propidx = of_property_match_string(np, "clock-names", "i2s_refclk");
 139         if (propidx >= 0)
 140                 i2s_refclk_name = of_clk_get_parent_name(np, propidx);
 141
 142         propidx = of_property_match_string(np, "clock-names", "frac_clk0");
 143         if (propidx >= 0)
 144                 frac_clk_name[0] = of_clk_get_parent_name(np, propidx);
 145         propidx = of_property_match_string(np, "clock-names", "frac_clk1");
 146         if (propidx >= 0)
 147                 frac_clk_name[1] = of_clk_get_parent_name(np, propidx);
 148
 149         spin_lock_init(&clkdata->i2scfg_lock);
 150
 151         clks[ARTPEC6_CLK_NAND_CLKA] =
 152             clk_register_fixed_factor(dev, "nand_clka", "cpu", 0, 1, 8);
 153         clks[ARTPEC6_CLK_NAND_CLKB] =
 154             clk_register_fixed_rate(dev, "nand_clkb", sys_refclk_name, 0,
 155                                     100000000);
 156         clks[ARTPEC6_CLK_ETH_ACLK] =
 157             clk_register_fixed_factor(dev, "eth_aclk", "cpu", 0, 1, 4);
 158         clks[ARTPEC6_CLK_DMA_ACLK] =
 159             clk_register_fixed_factor(dev, "dma_aclk", "cpu", 0, 1, 4);
 160         clks[ARTPEC6_CLK_PTP_REF] =
 161             clk_register_fixed_rate(dev, "ptp_ref", sys_refclk_name, 0,
 162                                     100000000);
 163         clks[ARTPEC6_CLK_SD_PCLK] =
 164             clk_register_fixed_rate(dev, "sd_pclk", sys_refclk_name, 0,
 165                                     100000000);
 166         clks[ARTPEC6_CLK_SD_IMCLK] =
 167             clk_register_fixed_rate(dev, "sd_imclk", sys_refclk_name, 0,
 168                                     100000000);
 169         clks[ARTPEC6_CLK_I2S_HST] =
 170             clk_register_fixed_factor(dev, "i2s_hst", "cpu", 0, 1, 8);
 171
 172         for (i = 0; i < NUM_I2S_CLOCKS; ++i) {
 173                 if (i2s_refclk_name && frac_clk_name[i]) {
 174                         i2s_mux_parents[0] = frac_clk_name[i];
 175                         i2s_mux_parents[1] = i2s_refclk_name;
 176
 177                         clks[i2s_clk_indexes[i]] =
 178                             clk_register_mux(dev, i2s_clk_names[i],
 179                                              i2s_mux_parents, 2,
 180                                              CLK_SET_RATE_NO_REPARENT |
 181                                              CLK_SET_RATE_PARENT,
 182                                              clkdata->syscon_base + 0x14, i, 1,
 183                                              0, &clkdata->i2scfg_lock);
 184                 } else if (frac_clk_name[i]) {
 185                         /* Lock the mux for internal clock reference. */
 186                         muxreg = readl(clkdata->syscon_base + 0x14);
 187                         muxreg &= ~BIT(i);
 188                         writel(muxreg, clkdata->syscon_base + 0x14);
 189                         clks[i2s_clk_indexes[i]] =
 190                             clk_register_fixed_factor(dev, i2s_clk_names[i],
 191                                                       frac_clk_name[i], 0, 1,
 192                                                       1);
 193                 } else if (i2s_refclk_name) {
 194                         /* Lock the mux for external clock reference. */
 195                         muxreg = readl(clkdata->syscon_base + 0x14);
 196                         muxreg |= BIT(i);
 197                         writel(muxreg, clkdata->syscon_base + 0x14);
 198                         clks[i2s_clk_indexes[i]] =
 199                             clk_register_fixed_factor(dev, i2s_clk_names[i],
 200                                                       i2s_refclk_name, 0, 1, 1);
 201                 }
 202         }
 203
 204         clks[ARTPEC6_CLK_I2C] =
 205             clk_register_fixed_rate(dev, "i2c", sys_refclk_name, 0, 100000000);
 206
 207         clks[ARTPEC6_CLK_SYS_TIMER] =
 208             clk_register_fixed_rate(dev, "timer", sys_refclk_name, 0,
 209                                     100000000);
 210         clks[ARTPEC6_CLK_FRACDIV_IN] =
 211             clk_register_fixed_rate(dev, "fracdiv_in", sys_refclk_name, 0,
 212                                     600000000);
 213
 214         for (i = 0; i < ARTPEC6_CLK_NUMCLOCKS; ++i) {
 215                 if (IS_ERR(clks[i]) && PTR_ERR(clks[i]) != -EPROBE_DEFER) {
 216                         dev_err(dev,
 217                                 "Failed to register clock at index %d err=%ld\n",
 218                                 i, PTR_ERR(clks[i]));
 219                         err = PTR_ERR(clks[i]);
 220                 }
 221         }
 222
 223         return err;
 224 }
 225
 226 static const struct of_device_id artpec_clkctrl_of_match[] = {
 227         { .compatible = "axis,artpec6-clkctrl" },
 228         {}
 229 };
 230
 231 static struct platform_driver artpec6_clkctrl_driver = {
 232         .probe = artpec6_clkctrl_probe,
 233         .driver = {
 234                    .name = "artpec6_clkctrl",
 235                    .of_match_table = artpec_clkctrl_of_match,
 236         },
 237 };
 238
 239 builtin_platform_driver(artpec6_clkctrl_driver);