1 /* 2 * OMAP gate clock support 3 * 4 * Copyright (C) 2013 Texas Instruments, Inc. 5 * 6 * Tero Kristo <t-kristo@ti.com> 7 * 8 * This program is free software; you can redistribute it and/or modify 9 * it under the terms of the GNU General Public License version 2 as 10 * published by the Free Software Foundation. 11 * 12 * This program is distributed "as is" WITHOUT ANY WARRANTY of any 13 * kind, whether express or implied; without even the implied warranty 14 * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 15 * GNU General Public License for more details. 16 */ 17 18 #include <linux/clk-provider.h> 19 #include <linux/slab.h> 20 #include <linux/io.h> 21 #include <linux/of.h> 22 #include <linux/of_address.h> 23 #include <linux/clk/ti.h> 24 25 #include "clock.h" 26 27 #undef pr_fmt 28 #define pr_fmt(fmt) "%s: " fmt, __func__ 29 30 static int omap36xx_gate_clk_enable_with_hsdiv_restore(struct clk_hw *clk); 31 32 static const struct clk_ops omap_gate_clkdm_clk_ops = { 33 .init = &omap2_init_clk_clkdm, 34 .enable = &omap2_clkops_enable_clkdm, 35 .disable = &omap2_clkops_disable_clkdm, 36 }; 37 38 const struct clk_ops omap_gate_clk_ops = { 39 .init = &omap2_init_clk_clkdm, 40 .enable = &omap2_dflt_clk_enable, 41 .disable = &omap2_dflt_clk_disable, 42 .is_enabled = &omap2_dflt_clk_is_enabled, 43 }; 44 45 static const struct clk_ops omap_gate_clk_hsdiv_restore_ops = { 46 .init = &omap2_init_clk_clkdm, 47 .enable = &omap36xx_gate_clk_enable_with_hsdiv_restore, 48 .disable = &omap2_dflt_clk_disable, 49 .is_enabled = &omap2_dflt_clk_is_enabled, 50 }; 51 52 /** 53 * omap36xx_gate_clk_enable_with_hsdiv_restore - enable clocks suffering 54 * from HSDivider PWRDN problem Implements Errata ID: i556. 55 * @clk: DPLL output struct clk 56 * 57 * 3630 only: dpll3_m3_ck, dpll4_m2_ck, dpll4_m3_ck, dpll4_m4_ck, 58 * dpll4_m5_ck & dpll4_m6_ck dividers gets loaded with reset 59 * valueafter their respective PWRDN bits are set. Any dummy write 60 * (Any other value different from the Read value) to the 61 * corresponding CM_CLKSEL register will refresh the dividers. 62 */ 63 static int omap36xx_gate_clk_enable_with_hsdiv_restore(struct clk_hw *hw) 64 { 65 struct clk_omap_divider *parent; 66 struct clk_hw *parent_hw; 67 u32 dummy_v, orig_v; 68 int ret; 69 70 /* Clear PWRDN bit of HSDIVIDER */ 71 ret = omap2_dflt_clk_enable(hw); 72 73 /* Parent is the x2 node, get parent of parent for the m2 div */ 74 parent_hw = clk_hw_get_parent(clk_hw_get_parent(hw)); 75 parent = to_clk_omap_divider(parent_hw); 76 77 /* Restore the dividers */ 78 if (!ret) { 79 orig_v = ti_clk_ll_ops->clk_readl(&parent->reg); 80 dummy_v = orig_v; 81 82 /* Write any other value different from the Read value */ 83 dummy_v ^= (1 << parent->shift); 84 ti_clk_ll_ops->clk_writel(dummy_v, &parent->reg); 85 86 /* Write the original divider */ 87 ti_clk_ll_ops->clk_writel(orig_v, &parent->reg); 88 } 89 90 return ret; 91 } 92 93 static struct clk *_register_gate(struct device *dev, const char *name, 94 const char *parent_name, unsigned long flags, 95 struct clk_omap_reg *reg, u8 bit_idx, 96 u8 clk_gate_flags, const struct clk_ops *ops, 97 const struct clk_hw_omap_ops *hw_ops) 98 { 99 struct clk_init_data init = { NULL }; 100 struct clk_hw_omap *clk_hw; 101 struct clk *clk; 102 103 clk_hw = kzalloc(sizeof(*clk_hw), GFP_KERNEL); 104 if (!clk_hw) 105 return ERR_PTR(-ENOMEM); 106 107 clk_hw->hw.init = &init; 108 109 init.name = name; 110 init.ops = ops; 111 112 memcpy(&clk_hw->enable_reg, reg, sizeof(*reg)); 113 clk_hw->enable_bit = bit_idx; 114 clk_hw->ops = hw_ops; 115 116 clk_hw->flags = clk_gate_flags; 117 118 init.parent_names = &parent_name; 119 init.num_parents = 1; 120 121 init.flags = flags; 122 123 clk = ti_clk_register(NULL, &clk_hw->hw, name); 124 125 if (IS_ERR(clk)) 126 kfree(clk_hw); 127 128 return clk; 129 } 130 131 struct clk_hw *ti_clk_build_component_gate(struct ti_clk_gate *setup) 132 { 133 struct clk_hw_omap *gate; 134 struct clk_omap_reg *reg; 135 const struct clk_hw_omap_ops *ops = &clkhwops_wait; 136 137 if (!setup) 138 return NULL; 139 140 gate = kzalloc(sizeof(*gate), GFP_KERNEL); 141 if (!gate) 142 return ERR_PTR(-ENOMEM); 143 144 reg = (struct clk_omap_reg *)&gate->enable_reg; 145 reg->index = setup->module; 146 reg->offset = setup->reg; 147 148 gate->enable_bit = setup->bit_shift; 149 150 if (setup->flags & CLKF_NO_WAIT) 151 ops = NULL; 152 153 if (setup->flags & CLKF_INTERFACE) 154 ops = &clkhwops_iclk_wait; 155 156 gate->ops = ops; 157 158 return &gate->hw; 159 } 160 161 static void __init _of_ti_gate_clk_setup(struct device_node *node, 162 const struct clk_ops *ops, 163 const struct clk_hw_omap_ops *hw_ops) 164 { 165 struct clk *clk; 166 const char *parent_name; 167 struct clk_omap_reg reg; 168 u8 enable_bit = 0; 169 u32 val; 170 u32 flags = 0; 171 u8 clk_gate_flags = 0; 172 173 if (ops != &omap_gate_clkdm_clk_ops) { 174 if (ti_clk_get_reg_addr(node, 0, ®)) 175 return; 176 177 if (!of_property_read_u32(node, "ti,bit-shift", &val)) 178 enable_bit = val; 179 } 180 181 if (of_clk_get_parent_count(node) != 1) { 182 pr_err("%s must have 1 parent\n", node->name); 183 return; 184 } 185 186 parent_name = of_clk_get_parent_name(node, 0); 187 188 if (of_property_read_bool(node, "ti,set-rate-parent")) 189 flags |= CLK_SET_RATE_PARENT; 190 191 if (of_property_read_bool(node, "ti,set-bit-to-disable")) 192 clk_gate_flags |= INVERT_ENABLE; 193 194 clk = _register_gate(NULL, node->name, parent_name, flags, ®, 195 enable_bit, clk_gate_flags, ops, hw_ops); 196 197 if (!IS_ERR(clk)) 198 of_clk_add_provider(node, of_clk_src_simple_get, clk); 199 } 200 201 static void __init 202 _of_ti_composite_gate_clk_setup(struct device_node *node, 203 const struct clk_hw_omap_ops *hw_ops) 204 { 205 struct clk_hw_omap *gate; 206 u32 val = 0; 207 208 gate = kzalloc(sizeof(*gate), GFP_KERNEL); 209 if (!gate) 210 return; 211 212 if (ti_clk_get_reg_addr(node, 0, &gate->enable_reg)) 213 goto cleanup; 214 215 of_property_read_u32(node, "ti,bit-shift", &val); 216 217 gate->enable_bit = val; 218 gate->ops = hw_ops; 219 220 if (!ti_clk_add_component(node, &gate->hw, CLK_COMPONENT_TYPE_GATE)) 221 return; 222 223 cleanup: 224 kfree(gate); 225 } 226 227 static void __init 228 of_ti_composite_no_wait_gate_clk_setup(struct device_node *node) 229 { 230 _of_ti_composite_gate_clk_setup(node, NULL); 231 } 232 CLK_OF_DECLARE(ti_composite_no_wait_gate_clk, "ti,composite-no-wait-gate-clock", 233 of_ti_composite_no_wait_gate_clk_setup); 234 235 #if defined(CONFIG_ARCH_OMAP2) || defined(CONFIG_ARCH_OMAP3) 236 static void __init of_ti_composite_interface_clk_setup(struct device_node *node) 237 { 238 _of_ti_composite_gate_clk_setup(node, &clkhwops_iclk_wait); 239 } 240 CLK_OF_DECLARE(ti_composite_interface_clk, "ti,composite-interface-clock", 241 of_ti_composite_interface_clk_setup); 242 #endif 243 244 static void __init of_ti_composite_gate_clk_setup(struct device_node *node) 245 { 246 _of_ti_composite_gate_clk_setup(node, &clkhwops_wait); 247 } 248 CLK_OF_DECLARE(ti_composite_gate_clk, "ti,composite-gate-clock", 249 of_ti_composite_gate_clk_setup); 250 251 252 static void __init of_ti_clkdm_gate_clk_setup(struct device_node *node) 253 { 254 _of_ti_gate_clk_setup(node, &omap_gate_clkdm_clk_ops, NULL); 255 } 256 CLK_OF_DECLARE(ti_clkdm_gate_clk, "ti,clkdm-gate-clock", 257 of_ti_clkdm_gate_clk_setup); 258 259 static void __init of_ti_hsdiv_gate_clk_setup(struct device_node *node) 260 { 261 _of_ti_gate_clk_setup(node, &omap_gate_clk_hsdiv_restore_ops, 262 &clkhwops_wait); 263 } 264 CLK_OF_DECLARE(ti_hsdiv_gate_clk, "ti,hsdiv-gate-clock", 265 of_ti_hsdiv_gate_clk_setup); 266 267 static void __init of_ti_gate_clk_setup(struct device_node *node) 268 { 269 _of_ti_gate_clk_setup(node, &omap_gate_clk_ops, NULL); 270 } 271 CLK_OF_DECLARE(ti_gate_clk, "ti,gate-clock", of_ti_gate_clk_setup); 272 273 static void __init of_ti_wait_gate_clk_setup(struct device_node *node) 274 { 275 _of_ti_gate_clk_setup(node, &omap_gate_clk_ops, &clkhwops_wait); 276 } 277 CLK_OF_DECLARE(ti_wait_gate_clk, "ti,wait-gate-clock", 278 of_ti_wait_gate_clk_setup); 279 280 #ifdef CONFIG_ARCH_OMAP3 281 static void __init of_ti_am35xx_gate_clk_setup(struct device_node *node) 282 { 283 _of_ti_gate_clk_setup(node, &omap_gate_clk_ops, 284 &clkhwops_am35xx_ipss_module_wait); 285 } 286 CLK_OF_DECLARE(ti_am35xx_gate_clk, "ti,am35xx-gate-clock", 287 of_ti_am35xx_gate_clk_setup); 288 289 static void __init of_ti_dss_gate_clk_setup(struct device_node *node) 290 { 291 _of_ti_gate_clk_setup(node, &omap_gate_clk_ops, 292 &clkhwops_omap3430es2_dss_usbhost_wait); 293 } 294 CLK_OF_DECLARE(ti_dss_gate_clk, "ti,dss-gate-clock", 295 of_ti_dss_gate_clk_setup); 296 #endif 297