drivers/clk/mvebu/ap806-system-controller.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * Marvell Armada AP806 System Controller
   4  *
   5  * Copyright (C) 2016 Marvell
   6  *
   7  * Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
   8  *
   9  */
  10
  11 #define pr_fmt(fmt) "ap806-system-controller: " fmt
  12
  13 #include <linux/clk-provider.h>
  14 #include <linux/mfd/syscon.h>
  15 #include <linux/init.h>
  16 #include <linux/of.h>
  17 #include <linux/of_address.h>
  18 #include <linux/platform_device.h>
  19 #include <linux/regmap.h>
  20
  21 #define AP806_SAR_REG                   0x400
  22 #define AP806_SAR_CLKFREQ_MODE_MASK     0x1f
  23
  24 #define AP806_CLK_NUM                   5
  25
  26 static struct clk *ap806_clks[AP806_CLK_NUM];
  27
  28 static struct clk_onecell_data ap806_clk_data = {
  29         .clks = ap806_clks,
  30         .clk_num = AP806_CLK_NUM,
  31 };
  32
  33 static char *ap806_unique_name(struct device *dev, struct device_node *np,
  34                                char *name)
  35 {
  36         const __be32 *reg;
  37         u64 addr;
  38
  39         reg = of_get_property(np, "reg", NULL);
  40         addr = of_translate_address(np, reg);
  41         return devm_kasprintf(dev, GFP_KERNEL, "%llx-%s",
  42                         (unsigned long long)addr, name);
  43 }
  44
  45 static int ap806_syscon_common_probe(struct platform_device *pdev,
  46                                      struct device_node *syscon_node)
  47 {
  48         unsigned int freq_mode, cpuclk_freq;
  49         const char *name, *fixedclk_name;
  50         struct device *dev = &pdev->dev;
  51         struct device_node *np = dev->of_node;
  52         struct regmap *regmap;
  53         u32 reg;
  54         int ret;
  55
  56         regmap = syscon_node_to_regmap(syscon_node);
  57         if (IS_ERR(regmap)) {
  58                 dev_err(dev, "cannot get regmap\n");
  59                 return PTR_ERR(regmap);
  60         }
  61
  62         ret = regmap_read(regmap, AP806_SAR_REG, &reg);
  63         if (ret) {
  64                 dev_err(dev, "cannot read from regmap\n");
  65                 return ret;
  66         }
  67
  68         freq_mode = reg & AP806_SAR_CLKFREQ_MODE_MASK;
  69         switch (freq_mode) {
  70         case 0x0:
  71         case 0x1:
  72                 cpuclk_freq = 2000;
  73                 break;
  74         case 0x6:
  75         case 0x7:
  76                 cpuclk_freq = 1800;
  77                 break;
  78         case 0x4:
  79         case 0xB:
  80         case 0xD:
  81                 cpuclk_freq = 1600;
  82                 break;
  83         case 0x1a:
  84                 cpuclk_freq = 1400;
  85                 break;
  86         case 0x14:
  87         case 0x17:
  88                 cpuclk_freq = 1300;
  89                 break;
  90         case 0x19:
  91                 cpuclk_freq = 1200;
  92                 break;
  93         case 0x13:
  94         case 0x1d:
  95                 cpuclk_freq = 1000;
  96                 break;
  97         case 0x1c:
  98                 cpuclk_freq = 800;
  99                 break;
 100         case 0x1b:
 101                 cpuclk_freq = 600;
 102                 break;
 103         default:
 104                 dev_err(dev, "invalid SAR value\n");
 105                 return -EINVAL;
 106         }
 107
 108         /* Convert to hertz */
 109         cpuclk_freq *= 1000 * 1000;
 110
 111         /* CPU clocks depend on the Sample At Reset configuration */
 112         name = ap806_unique_name(dev, syscon_node, "cpu-cluster-0");
 113         ap806_clks[0] = clk_register_fixed_rate(dev, name, NULL,
 114                                                 0, cpuclk_freq);
 115         if (IS_ERR(ap806_clks[0])) {
 116                 ret = PTR_ERR(ap806_clks[0]);
 117                 goto fail0;
 118         }
 119
 120         name = ap806_unique_name(dev, syscon_node, "cpu-cluster-1");
 121         ap806_clks[1] = clk_register_fixed_rate(dev, name, NULL, 0,
 122                                                 cpuclk_freq);
 123         if (IS_ERR(ap806_clks[1])) {
 124                 ret = PTR_ERR(ap806_clks[1]);
 125                 goto fail1;
 126         }
 127
 128         /* Fixed clock is always 1200 Mhz */
 129         fixedclk_name = ap806_unique_name(dev, syscon_node, "fixed");
 130         ap806_clks[2] = clk_register_fixed_rate(dev, fixedclk_name, NULL,
 131                                                 0, 1200 * 1000 * 1000);
 132         if (IS_ERR(ap806_clks[2])) {
 133                 ret = PTR_ERR(ap806_clks[2]);
 134                 goto fail2;
 135         }
 136
 137         /* MSS Clock is fixed clock divided by 6 */
 138         name = ap806_unique_name(dev, syscon_node, "mss");
 139         ap806_clks[3] = clk_register_fixed_factor(NULL, name, fixedclk_name,
 140                                                   0, 1, 6);
 141         if (IS_ERR(ap806_clks[3])) {
 142                 ret = PTR_ERR(ap806_clks[3]);
 143                 goto fail3;
 144         }
 145
 146         /* SDIO(/eMMC) Clock is fixed clock divided by 3 */
 147         name = ap806_unique_name(dev, syscon_node, "sdio");
 148         ap806_clks[4] = clk_register_fixed_factor(NULL, name,
 149                                                   fixedclk_name,
 150                                                   0, 1, 3);
 151         if (IS_ERR(ap806_clks[4])) {
 152                 ret = PTR_ERR(ap806_clks[4]);
 153                 goto fail4;
 154         }
 155
 156         ret = of_clk_add_provider(np, of_clk_src_onecell_get, &ap806_clk_data);
 157         if (ret)
 158                 goto fail_clk_add;
 159
 160         return 0;
 161
 162 fail_clk_add:
 163         clk_unregister_fixed_factor(ap806_clks[4]);
 164 fail4:
 165         clk_unregister_fixed_factor(ap806_clks[3]);
 166 fail3:
 167         clk_unregister_fixed_rate(ap806_clks[2]);
 168 fail2:
 169         clk_unregister_fixed_rate(ap806_clks[1]);
 170 fail1:
 171         clk_unregister_fixed_rate(ap806_clks[0]);
 172 fail0:
 173         return ret;
 174 }
 175
 176 static int ap806_syscon_legacy_probe(struct platform_device *pdev)
 177 {
 178         dev_warn(&pdev->dev, FW_WARN "Using legacy device tree binding\n");
 179         dev_warn(&pdev->dev, FW_WARN "Update your device tree:\n");
 180         dev_warn(&pdev->dev, FW_WARN
 181                  "This binding won't be supported in future kernel\n");
 182
 183         return ap806_syscon_common_probe(pdev, pdev->dev.of_node);
 184
 185 }
 186
 187 static int ap806_clock_probe(struct platform_device *pdev)
 188 {
 189         return ap806_syscon_common_probe(pdev, pdev->dev.of_node->parent);
 190 }
 191
 192 static const struct of_device_id ap806_syscon_legacy_of_match[] = {
 193         { .compatible = "marvell,ap806-system-controller", },
 194         { }
 195 };
 196
 197 static struct platform_driver ap806_syscon_legacy_driver = {
 198         .probe = ap806_syscon_legacy_probe,
 199         .driver         = {
 200                 .name   = "marvell-ap806-system-controller",
 201                 .of_match_table = ap806_syscon_legacy_of_match,
 202                 .suppress_bind_attrs = true,
 203         },
 204 };
 205 builtin_platform_driver(ap806_syscon_legacy_driver);
 206
 207 static const struct of_device_id ap806_clock_of_match[] = {
 208         { .compatible = "marvell,ap806-clock", },
 209         { }
 210 };
 211
 212 static struct platform_driver ap806_clock_driver = {
 213         .probe = ap806_clock_probe,
 214         .driver         = {
 215                 .name   = "marvell-ap806-clock",
 216                 .of_match_table = ap806_clock_of_match,
 217                 .suppress_bind_attrs = true,
 218         },
 219 };
 220 builtin_platform_driver(ap806_clock_driver);