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 #define to_clk_divider(_hw) container_of(_hw, struct clk_divider, hw) 28 29 #undef pr_fmt 30 #define pr_fmt(fmt) "%s: " fmt, __func__ 31 32 static int omap36xx_gate_clk_enable_with_hsdiv_restore(struct clk_hw *clk); 33 34 static const struct clk_ops omap_gate_clkdm_clk_ops = { 35 .init = &omap2_init_clk_clkdm, 36 .enable = &omap2_clkops_enable_clkdm, 37 .disable = &omap2_clkops_disable_clkdm, 38 }; 39 40 static const struct clk_ops omap_gate_clk_ops = { 41 .init = &omap2_init_clk_clkdm, 42 .enable = &omap2_dflt_clk_enable, 43 .disable = &omap2_dflt_clk_disable, 44 .is_enabled = &omap2_dflt_clk_is_enabled, 45 }; 46 47 static const struct clk_ops omap_gate_clk_hsdiv_restore_ops = { 48 .init = &omap2_init_clk_clkdm, 49 .enable = &omap36xx_gate_clk_enable_with_hsdiv_restore, 50 .disable = &omap2_dflt_clk_disable, 51 .is_enabled = &omap2_dflt_clk_is_enabled, 52 }; 53 54 /** 55 * omap36xx_gate_clk_enable_with_hsdiv_restore - enable clocks suffering 56 * from HSDivider PWRDN problem Implements Errata ID: i556. 57 * @clk: DPLL output struct clk 58 * 59 * 3630 only: dpll3_m3_ck, dpll4_m2_ck, dpll4_m3_ck, dpll4_m4_ck, 60 * dpll4_m5_ck & dpll4_m6_ck dividers gets loaded with reset 61 * valueafter their respective PWRDN bits are set. Any dummy write 62 * (Any other value different from the Read value) to the 63 * corresponding CM_CLKSEL register will refresh the dividers. 64 */ 65 static int omap36xx_gate_clk_enable_with_hsdiv_restore(struct clk_hw *clk) 66 { 67 struct clk_divider *parent; 68 struct clk_hw *parent_hw; 69 u32 dummy_v, orig_v; 70 int ret; 71 72 /* Clear PWRDN bit of HSDIVIDER */ 73 ret = omap2_dflt_clk_enable(clk); 74 75 /* Parent is the x2 node, get parent of parent for the m2 div */ 76 parent_hw = __clk_get_hw(__clk_get_parent(__clk_get_parent(clk->clk))); 77 parent = to_clk_divider(parent_hw); 78 79 /* Restore the dividers */ 80 if (!ret) { 81 orig_v = ti_clk_ll_ops->clk_readl(parent->reg); 82 dummy_v = orig_v; 83 84 /* Write any other value different from the Read value */ 85 dummy_v ^= (1 << parent->shift); 86 ti_clk_ll_ops->clk_writel(dummy_v, parent->reg); 87 88 /* Write the original divider */ 89 ti_clk_ll_ops->clk_writel(orig_v, parent->reg); 90 } 91 92 return ret; 93 } 94 95 static struct clk *_register_gate(struct device *dev, const char *name, 96 const char *parent_name, unsigned long flags, 97 void __iomem *reg, u8 bit_idx, 98 u8 clk_gate_flags, const struct clk_ops *ops, 99 const struct clk_hw_omap_ops *hw_ops) 100 { 101 struct clk_init_data init = { NULL }; 102 struct clk_hw_omap *clk_hw; 103 struct clk *clk; 104 105 clk_hw = kzalloc(sizeof(*clk_hw), GFP_KERNEL); 106 if (!clk_hw) 107 return ERR_PTR(-ENOMEM); 108 109 clk_hw->hw.init = &init; 110 111 init.name = name; 112 init.ops = ops; 113 114 clk_hw->enable_reg = reg; 115 clk_hw->enable_bit = bit_idx; 116 clk_hw->ops = hw_ops; 117 118 clk_hw->flags = MEMMAP_ADDRESSING | clk_gate_flags; 119 120 init.parent_names = &parent_name; 121 init.num_parents = 1; 122 123 init.flags = flags; 124 125 clk = clk_register(NULL, &clk_hw->hw); 126 127 if (IS_ERR(clk)) 128 kfree(clk_hw); 129 130 return clk; 131 } 132 133 #if defined(CONFIG_ARCH_OMAP3) && defined(CONFIG_ATAGS) 134 struct clk *ti_clk_register_gate(struct ti_clk *setup) 135 { 136 const struct clk_ops *ops = &omap_gate_clk_ops; 137 const struct clk_hw_omap_ops *hw_ops = NULL; 138 u32 reg; 139 struct clk_omap_reg *reg_setup; 140 u32 flags = 0; 141 u8 clk_gate_flags = 0; 142 struct ti_clk_gate *gate; 143 144 gate = setup->data; 145 146 if (gate->flags & CLKF_INTERFACE) 147 return ti_clk_register_interface(setup); 148 149 reg_setup = (struct clk_omap_reg *)® 150 151 if (gate->flags & CLKF_SET_RATE_PARENT) 152 flags |= CLK_SET_RATE_PARENT; 153 154 if (gate->flags & CLKF_SET_BIT_TO_DISABLE) 155 clk_gate_flags |= INVERT_ENABLE; 156 157 if (gate->flags & CLKF_HSDIV) { 158 ops = &omap_gate_clk_hsdiv_restore_ops; 159 hw_ops = &clkhwops_wait; 160 } 161 162 if (gate->flags & CLKF_DSS) 163 hw_ops = &clkhwops_omap3430es2_dss_usbhost_wait; 164 165 if (gate->flags & CLKF_WAIT) 166 hw_ops = &clkhwops_wait; 167 168 if (gate->flags & CLKF_CLKDM) 169 ops = &omap_gate_clkdm_clk_ops; 170 171 if (gate->flags & CLKF_AM35XX) 172 hw_ops = &clkhwops_am35xx_ipss_module_wait; 173 174 reg_setup->index = gate->module; 175 reg_setup->offset = gate->reg; 176 177 return _register_gate(NULL, setup->name, gate->parent, flags, 178 (void __iomem *)reg, gate->bit_shift, 179 clk_gate_flags, ops, hw_ops); 180 } 181 182 struct clk_hw *ti_clk_build_component_gate(struct ti_clk_gate *setup) 183 { 184 struct clk_hw_omap *gate; 185 struct clk_omap_reg *reg; 186 const struct clk_hw_omap_ops *ops = &clkhwops_wait; 187 188 if (!setup) 189 return NULL; 190 191 gate = kzalloc(sizeof(*gate), GFP_KERNEL); 192 if (!gate) 193 return ERR_PTR(-ENOMEM); 194 195 reg = (struct clk_omap_reg *)&gate->enable_reg; 196 reg->index = setup->module; 197 reg->offset = setup->reg; 198 199 gate->enable_bit = setup->bit_shift; 200 201 if (setup->flags & CLKF_NO_WAIT) 202 ops = NULL; 203 204 if (setup->flags & CLKF_INTERFACE) 205 ops = &clkhwops_iclk_wait; 206 207 gate->ops = ops; 208 gate->flags = MEMMAP_ADDRESSING; 209 210 return &gate->hw; 211 } 212 #endif 213 214 static void __init _of_ti_gate_clk_setup(struct device_node *node, 215 const struct clk_ops *ops, 216 const struct clk_hw_omap_ops *hw_ops) 217 { 218 struct clk *clk; 219 const char *parent_name; 220 void __iomem *reg = NULL; 221 u8 enable_bit = 0; 222 u32 val; 223 u32 flags = 0; 224 u8 clk_gate_flags = 0; 225 226 if (ops != &omap_gate_clkdm_clk_ops) { 227 reg = ti_clk_get_reg_addr(node, 0); 228 if (IS_ERR(reg)) 229 return; 230 231 if (!of_property_read_u32(node, "ti,bit-shift", &val)) 232 enable_bit = val; 233 } 234 235 if (of_clk_get_parent_count(node) != 1) { 236 pr_err("%s must have 1 parent\n", node->name); 237 return; 238 } 239 240 parent_name = of_clk_get_parent_name(node, 0); 241 242 if (of_property_read_bool(node, "ti,set-rate-parent")) 243 flags |= CLK_SET_RATE_PARENT; 244 245 if (of_property_read_bool(node, "ti,set-bit-to-disable")) 246 clk_gate_flags |= INVERT_ENABLE; 247 248 clk = _register_gate(NULL, node->name, parent_name, flags, reg, 249 enable_bit, clk_gate_flags, ops, hw_ops); 250 251 if (!IS_ERR(clk)) 252 of_clk_add_provider(node, of_clk_src_simple_get, clk); 253 } 254 255 static void __init 256 _of_ti_composite_gate_clk_setup(struct device_node *node, 257 const struct clk_hw_omap_ops *hw_ops) 258 { 259 struct clk_hw_omap *gate; 260 u32 val = 0; 261 262 gate = kzalloc(sizeof(*gate), GFP_KERNEL); 263 if (!gate) 264 return; 265 266 gate->enable_reg = ti_clk_get_reg_addr(node, 0); 267 if (IS_ERR(gate->enable_reg)) 268 goto cleanup; 269 270 of_property_read_u32(node, "ti,bit-shift", &val); 271 272 gate->enable_bit = val; 273 gate->ops = hw_ops; 274 gate->flags = MEMMAP_ADDRESSING; 275 276 if (!ti_clk_add_component(node, &gate->hw, CLK_COMPONENT_TYPE_GATE)) 277 return; 278 279 cleanup: 280 kfree(gate); 281 } 282 283 static void __init 284 of_ti_composite_no_wait_gate_clk_setup(struct device_node *node) 285 { 286 _of_ti_composite_gate_clk_setup(node, NULL); 287 } 288 CLK_OF_DECLARE(ti_composite_no_wait_gate_clk, "ti,composite-no-wait-gate-clock", 289 of_ti_composite_no_wait_gate_clk_setup); 290 291 #if defined(CONFIG_ARCH_OMAP2) || defined(CONFIG_ARCH_OMAP3) 292 static void __init of_ti_composite_interface_clk_setup(struct device_node *node) 293 { 294 _of_ti_composite_gate_clk_setup(node, &clkhwops_iclk_wait); 295 } 296 CLK_OF_DECLARE(ti_composite_interface_clk, "ti,composite-interface-clock", 297 of_ti_composite_interface_clk_setup); 298 #endif 299 300 static void __init of_ti_composite_gate_clk_setup(struct device_node *node) 301 { 302 _of_ti_composite_gate_clk_setup(node, &clkhwops_wait); 303 } 304 CLK_OF_DECLARE(ti_composite_gate_clk, "ti,composite-gate-clock", 305 of_ti_composite_gate_clk_setup); 306 307 308 static void __init of_ti_clkdm_gate_clk_setup(struct device_node *node) 309 { 310 _of_ti_gate_clk_setup(node, &omap_gate_clkdm_clk_ops, NULL); 311 } 312 CLK_OF_DECLARE(ti_clkdm_gate_clk, "ti,clkdm-gate-clock", 313 of_ti_clkdm_gate_clk_setup); 314 315 static void __init of_ti_hsdiv_gate_clk_setup(struct device_node *node) 316 { 317 _of_ti_gate_clk_setup(node, &omap_gate_clk_hsdiv_restore_ops, 318 &clkhwops_wait); 319 } 320 CLK_OF_DECLARE(ti_hsdiv_gate_clk, "ti,hsdiv-gate-clock", 321 of_ti_hsdiv_gate_clk_setup); 322 323 static void __init of_ti_gate_clk_setup(struct device_node *node) 324 { 325 _of_ti_gate_clk_setup(node, &omap_gate_clk_ops, NULL); 326 } 327 CLK_OF_DECLARE(ti_gate_clk, "ti,gate-clock", of_ti_gate_clk_setup); 328 329 static void __init of_ti_wait_gate_clk_setup(struct device_node *node) 330 { 331 _of_ti_gate_clk_setup(node, &omap_gate_clk_ops, &clkhwops_wait); 332 } 333 CLK_OF_DECLARE(ti_wait_gate_clk, "ti,wait-gate-clock", 334 of_ti_wait_gate_clk_setup); 335 336 #ifdef CONFIG_ARCH_OMAP3 337 static void __init of_ti_am35xx_gate_clk_setup(struct device_node *node) 338 { 339 _of_ti_gate_clk_setup(node, &omap_gate_clk_ops, 340 &clkhwops_am35xx_ipss_module_wait); 341 } 342 CLK_OF_DECLARE(ti_am35xx_gate_clk, "ti,am35xx-gate-clock", 343 of_ti_am35xx_gate_clk_setup); 344 345 static void __init of_ti_dss_gate_clk_setup(struct device_node *node) 346 { 347 _of_ti_gate_clk_setup(node, &omap_gate_clk_ops, 348 &clkhwops_omap3430es2_dss_usbhost_wait); 349 } 350 CLK_OF_DECLARE(ti_dss_gate_clk, "ti,dss-gate-clock", 351 of_ti_dss_gate_clk_setup); 352 #endif 353