drivers/clk/shmobile/clk-sh73a0.c

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