drivers/clk/renesas/clk-sh73a0.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * sh73a0 Core CPG Clocks
   4  *
   5  * Copyright (C) 2014  Ulrich Hecht
   6  */
   7
   8 #include <linux/clk-provider.h>
   9 #include <linux/clk/renesas.h>
  10 #include <linux/init.h>
  11 #include <linux/io.h>
  12 #include <linux/kernel.h>
  13 #include <linux/of.h>
  14 #include <linux/of_address.h>
  15 #include <linux/slab.h>
  16 #include <linux/spinlock.h>
  17
  18 struct sh73a0_cpg {
  19         struct clk_onecell_data data;
  20         spinlock_t lock;
  21         void __iomem *reg;
  22 };
  23
  24 #define CPG_FRQCRA      0x00
  25 #define CPG_FRQCRB      0x04
  26 #define CPG_SD0CKCR     0x74
  27 #define CPG_SD1CKCR     0x78
  28 #define CPG_SD2CKCR     0x7c
  29 #define CPG_PLLECR      0xd0
  30 #define CPG_PLL0CR      0xd8
  31 #define CPG_PLL1CR      0x28
  32 #define CPG_PLL2CR      0x2c
  33 #define CPG_PLL3CR      0xdc
  34 #define CPG_CKSCR       0xc0
  35 #define CPG_DSI0PHYCR   0x6c
  36 #define CPG_DSI1PHYCR   0x70
  37
  38 #define CLK_ENABLE_ON_INIT BIT(0)
  39
  40 struct div4_clk {
  41         const char *name;
  42         const char *parent;
  43         unsigned int reg;
  44         unsigned int shift;
  45 };
  46
  47 static const struct div4_clk div4_clks[] = {
  48         { "zg", "pll0", CPG_FRQCRA, 16 },
  49         { "m3", "pll1", CPG_FRQCRA, 12 },
  50         { "b",  "pll1", CPG_FRQCRA,  8 },
  51         { "m1", "pll1", CPG_FRQCRA,  4 },
  52         { "m2", "pll1", CPG_FRQCRA,  0 },
  53         { "zx", "pll1", CPG_FRQCRB, 12 },
  54         { "hp", "pll1", CPG_FRQCRB,  4 },
  55         { NULL, NULL, 0, 0 },
  56 };
  57
  58 static const struct clk_div_table div4_div_table[] = {
  59         { 0, 2 }, { 1, 3 }, { 2, 4 }, { 3, 6 }, { 4, 8 }, { 5, 12 },
  60         { 6, 16 }, { 7, 18 }, { 8, 24 }, { 10, 36 }, { 11, 48 },
  61         { 12, 7 }, { 0, 0 }
  62 };
  63
  64 static const struct clk_div_table z_div_table[] = {
  65         /* ZSEL == 0 */
  66         { 0, 1 }, { 1, 1 }, { 2, 1 }, { 3, 1 }, { 4, 1 }, { 5, 1 },
  67         { 6, 1 }, { 7, 1 }, { 8, 1 }, { 9, 1 }, { 10, 1 }, { 11, 1 },
  68         { 12, 1 }, { 13, 1 }, { 14, 1 }, { 15, 1 },
  69         /* ZSEL == 1 */
  70         { 16, 2 }, { 17, 3 }, { 18, 4 }, { 19, 6 }, { 20, 8 }, { 21, 12 },
  71         { 22, 16 }, { 24, 24 }, { 27, 48 }, { 0, 0 }
  72 };
  73
  74 static struct clk * __init
  75 sh73a0_cpg_register_clock(struct device_node *np, struct sh73a0_cpg *cpg,
  76                              const char *name)
  77 {
  78         const struct clk_div_table *table = NULL;
  79         unsigned int shift, reg, width;
  80         const char *parent_name = NULL;
  81         unsigned int mult = 1;
  82         unsigned int div = 1;
  83
  84         if (!strcmp(name, "main")) {
  85                 /* extal1, extal1_div2, extal2, extal2_div2 */
  86                 u32 parent_idx = (readl(cpg->reg + CPG_CKSCR) >> 28) & 3;
  87
  88                 parent_name = of_clk_get_parent_name(np, parent_idx >> 1);
  89                 div = (parent_idx & 1) + 1;
  90         } else if (!strncmp(name, "pll", 3)) {
  91                 void __iomem *enable_reg = cpg->reg;
  92                 u32 enable_bit = name[3] - '0';
  93
  94                 parent_name = "main";
  95                 switch (enable_bit) {
  96                 case 0:
  97                         enable_reg += CPG_PLL0CR;
  98                         break;
  99                 case 1:
 100                         enable_reg += CPG_PLL1CR;
 101                         break;
 102                 case 2:
 103                         enable_reg += CPG_PLL2CR;
 104                         break;
 105                 case 3:
 106                         enable_reg += CPG_PLL3CR;
 107                         break;
 108                 default:
 109                         return ERR_PTR(-EINVAL);
 110                 }
 111                 if (readl(cpg->reg + CPG_PLLECR) & BIT(enable_bit)) {
 112                         mult = ((readl(enable_reg) >> 24) & 0x3f) + 1;
 113                         /* handle CFG bit for PLL1 and PLL2 */
 114                         if (enable_bit == 1 || enable_bit == 2)
 115                                 if (readl(enable_reg) & BIT(20))
 116                                         mult *= 2;
 117                 }
 118         } else if (!strcmp(name, "dsi0phy") || !strcmp(name, "dsi1phy")) {
 119                 u32 phy_no = name[3] - '0';
 120                 void __iomem *dsi_reg = cpg->reg +
 121                         (phy_no ? CPG_DSI1PHYCR : CPG_DSI0PHYCR);
 122
 123                 parent_name = phy_no ? "dsi1pck" : "dsi0pck";
 124                 mult = __raw_readl(dsi_reg);
 125                 if (!(mult & 0x8000))
 126                         mult = 1;
 127                 else
 128                         mult = (mult & 0x3f) + 1;
 129         } else if (!strcmp(name, "z")) {
 130                 parent_name = "pll0";
 131                 table = z_div_table;
 132                 reg = CPG_FRQCRB;
 133                 shift = 24;
 134                 width = 5;
 135         } else {
 136                 const struct div4_clk *c;
 137
 138                 for (c = div4_clks; c->name; c++) {
 139                         if (!strcmp(name, c->name)) {
 140                                 parent_name = c->parent;
 141                                 table = div4_div_table;
 142                                 reg = c->reg;
 143                                 shift = c->shift;
 144                                 width = 4;
 145                                 break;
 146                         }
 147                 }
 148                 if (!c->name)
 149                         return ERR_PTR(-EINVAL);
 150         }
 151
 152         if (!table) {
 153                 return clk_register_fixed_factor(NULL, name, parent_name, 0,
 154                                                  mult, div);
 155         } else {
 156                 return clk_register_divider_table(NULL, name, parent_name, 0,
 157                                                   cpg->reg + reg, shift, width, 0,
 158                                                   table, &cpg->lock);
 159         }
 160 }
 161
 162 static void __init sh73a0_cpg_clocks_init(struct device_node *np)
 163 {
 164         struct sh73a0_cpg *cpg;
 165         struct clk **clks;
 166         unsigned int i;
 167         int num_clks;
 168
 169         num_clks = of_property_count_strings(np, "clock-output-names");
 170         if (num_clks < 0) {
 171                 pr_err("%s: failed to count clocks\n", __func__);
 172                 return;
 173         }
 174
 175         cpg = kzalloc(sizeof(*cpg), GFP_KERNEL);
 176         clks = kcalloc(num_clks, sizeof(*clks), GFP_KERNEL);
 177         if (cpg == NULL || clks == NULL) {
 178                 /* We're leaking memory on purpose, there's no point in cleaning
 179                  * up as the system won't boot anyway.
 180                  */
 181                 return;
 182         }
 183
 184         spin_lock_init(&cpg->lock);
 185
 186         cpg->data.clks = clks;
 187         cpg->data.clk_num = num_clks;
 188
 189         cpg->reg = of_iomap(np, 0);
 190         if (WARN_ON(cpg->reg == NULL))
 191                 return;
 192
 193         /* Set SDHI clocks to a known state */
 194         writel(0x108, cpg->reg + CPG_SD0CKCR);
 195         writel(0x108, cpg->reg + CPG_SD1CKCR);
 196         writel(0x108, cpg->reg + CPG_SD2CKCR);
 197
 198         for (i = 0; i < num_clks; ++i) {
 199                 const char *name;
 200                 struct clk *clk;
 201
 202                 of_property_read_string_index(np, "clock-output-names", i,
 203                                               &name);
 204
 205                 clk = sh73a0_cpg_register_clock(np, cpg, name);
 206                 if (IS_ERR(clk))
 207                         pr_err("%s: failed to register %pOFn %s clock (%ld)\n",
 208                                __func__, np, name, PTR_ERR(clk));
 209                 else
 210                         cpg->data.clks[i] = clk;
 211         }
 212
 213         of_clk_add_provider(np, of_clk_src_onecell_get, &cpg->data);
 214 }
 215 CLK_OF_DECLARE(sh73a0_cpg_clks, "renesas,sh73a0-cpg-clocks",
 216                sh73a0_cpg_clocks_init);