1 /* 2 * DRA7 ATL (Audio Tracking Logic) clock driver 3 * 4 * Copyright (C) 2013 Texas Instruments, Inc. 5 * 6 * Peter Ujfalusi <peter.ujfalusi@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/init.h> 19 #include <linux/clk.h> 20 #include <linux/clk-provider.h> 21 #include <linux/slab.h> 22 #include <linux/io.h> 23 #include <linux/of.h> 24 #include <linux/of_address.h> 25 #include <linux/platform_device.h> 26 #include <linux/pm_runtime.h> 27 #include <linux/clk/ti.h> 28 29 #include "clock.h" 30 31 #define DRA7_ATL_INSTANCES 4 32 33 #define DRA7_ATL_PPMR_REG(id) (0x200 + (id * 0x80)) 34 #define DRA7_ATL_BBSR_REG(id) (0x204 + (id * 0x80)) 35 #define DRA7_ATL_ATLCR_REG(id) (0x208 + (id * 0x80)) 36 #define DRA7_ATL_SWEN_REG(id) (0x210 + (id * 0x80)) 37 #define DRA7_ATL_BWSMUX_REG(id) (0x214 + (id * 0x80)) 38 #define DRA7_ATL_AWSMUX_REG(id) (0x218 + (id * 0x80)) 39 #define DRA7_ATL_PCLKMUX_REG(id) (0x21c + (id * 0x80)) 40 41 #define DRA7_ATL_SWEN BIT(0) 42 #define DRA7_ATL_DIVIDER_MASK (0x1f) 43 #define DRA7_ATL_PCLKMUX BIT(0) 44 struct dra7_atl_clock_info; 45 46 struct dra7_atl_desc { 47 struct clk *clk; 48 struct clk_hw hw; 49 struct dra7_atl_clock_info *cinfo; 50 int id; 51 52 bool probed; /* the driver for the IP has been loaded */ 53 bool valid; /* configured */ 54 bool enabled; 55 u32 bws; /* Baseband Word Select Mux */ 56 u32 aws; /* Audio Word Select Mux */ 57 u32 divider; /* Cached divider value */ 58 }; 59 60 struct dra7_atl_clock_info { 61 struct device *dev; 62 void __iomem *iobase; 63 64 struct dra7_atl_desc *cdesc; 65 }; 66 67 #define to_atl_desc(_hw) container_of(_hw, struct dra7_atl_desc, hw) 68 69 static inline void atl_write(struct dra7_atl_clock_info *cinfo, u32 reg, 70 u32 val) 71 { 72 __raw_writel(val, cinfo->iobase + reg); 73 } 74 75 static inline int atl_read(struct dra7_atl_clock_info *cinfo, u32 reg) 76 { 77 return __raw_readl(cinfo->iobase + reg); 78 } 79 80 static int atl_clk_enable(struct clk_hw *hw) 81 { 82 struct dra7_atl_desc *cdesc = to_atl_desc(hw); 83 84 if (!cdesc->probed) 85 goto out; 86 87 if (unlikely(!cdesc->valid)) 88 dev_warn(cdesc->cinfo->dev, "atl%d has not been configured\n", 89 cdesc->id); 90 pm_runtime_get_sync(cdesc->cinfo->dev); 91 92 atl_write(cdesc->cinfo, DRA7_ATL_ATLCR_REG(cdesc->id), 93 cdesc->divider - 1); 94 atl_write(cdesc->cinfo, DRA7_ATL_SWEN_REG(cdesc->id), DRA7_ATL_SWEN); 95 96 out: 97 cdesc->enabled = true; 98 99 return 0; 100 } 101 102 static void atl_clk_disable(struct clk_hw *hw) 103 { 104 struct dra7_atl_desc *cdesc = to_atl_desc(hw); 105 106 if (!cdesc->probed) 107 goto out; 108 109 atl_write(cdesc->cinfo, DRA7_ATL_SWEN_REG(cdesc->id), 0); 110 pm_runtime_put_sync(cdesc->cinfo->dev); 111 112 out: 113 cdesc->enabled = false; 114 } 115 116 static int atl_clk_is_enabled(struct clk_hw *hw) 117 { 118 struct dra7_atl_desc *cdesc = to_atl_desc(hw); 119 120 return cdesc->enabled; 121 } 122 123 static unsigned long atl_clk_recalc_rate(struct clk_hw *hw, 124 unsigned long parent_rate) 125 { 126 struct dra7_atl_desc *cdesc = to_atl_desc(hw); 127 128 return parent_rate / cdesc->divider; 129 } 130 131 static long atl_clk_round_rate(struct clk_hw *hw, unsigned long rate, 132 unsigned long *parent_rate) 133 { 134 unsigned divider; 135 136 divider = (*parent_rate + rate / 2) / rate; 137 if (divider > DRA7_ATL_DIVIDER_MASK + 1) 138 divider = DRA7_ATL_DIVIDER_MASK + 1; 139 140 return *parent_rate / divider; 141 } 142 143 static int atl_clk_set_rate(struct clk_hw *hw, unsigned long rate, 144 unsigned long parent_rate) 145 { 146 struct dra7_atl_desc *cdesc; 147 u32 divider; 148 149 if (!hw || !rate) 150 return -EINVAL; 151 152 cdesc = to_atl_desc(hw); 153 divider = ((parent_rate + rate / 2) / rate) - 1; 154 if (divider > DRA7_ATL_DIVIDER_MASK) 155 divider = DRA7_ATL_DIVIDER_MASK; 156 157 cdesc->divider = divider + 1; 158 159 return 0; 160 } 161 162 static const struct clk_ops atl_clk_ops = { 163 .enable = atl_clk_enable, 164 .disable = atl_clk_disable, 165 .is_enabled = atl_clk_is_enabled, 166 .recalc_rate = atl_clk_recalc_rate, 167 .round_rate = atl_clk_round_rate, 168 .set_rate = atl_clk_set_rate, 169 }; 170 171 static void __init of_dra7_atl_clock_setup(struct device_node *node) 172 { 173 struct dra7_atl_desc *clk_hw = NULL; 174 struct clk_init_data init = { NULL }; 175 const char **parent_names = NULL; 176 struct clk *clk; 177 int ret; 178 179 clk_hw = kzalloc(sizeof(*clk_hw), GFP_KERNEL); 180 if (!clk_hw) { 181 pr_err("%s: could not allocate dra7_atl_desc\n", __func__); 182 return; 183 } 184 185 clk_hw->hw.init = &init; 186 clk_hw->divider = 1; 187 init.name = node->name; 188 init.ops = &atl_clk_ops; 189 init.flags = CLK_IGNORE_UNUSED; 190 init.num_parents = of_clk_get_parent_count(node); 191 192 if (init.num_parents != 1) { 193 pr_err("%s: atl clock %pOFn must have 1 parent\n", __func__, 194 node); 195 goto cleanup; 196 } 197 198 parent_names = kzalloc(sizeof(char *), GFP_KERNEL); 199 200 if (!parent_names) 201 goto cleanup; 202 203 parent_names[0] = of_clk_get_parent_name(node, 0); 204 205 init.parent_names = parent_names; 206 207 clk = ti_clk_register(NULL, &clk_hw->hw, node->name); 208 209 if (!IS_ERR(clk)) { 210 ret = ti_clk_add_alias(NULL, clk, node->name); 211 if (ret) { 212 clk_unregister(clk); 213 goto cleanup; 214 } 215 of_clk_add_provider(node, of_clk_src_simple_get, clk); 216 kfree(parent_names); 217 return; 218 } 219 cleanup: 220 kfree(parent_names); 221 kfree(clk_hw); 222 } 223 CLK_OF_DECLARE(dra7_atl_clock, "ti,dra7-atl-clock", of_dra7_atl_clock_setup); 224 225 static int of_dra7_atl_clk_probe(struct platform_device *pdev) 226 { 227 struct device_node *node = pdev->dev.of_node; 228 struct dra7_atl_clock_info *cinfo; 229 int i; 230 int ret = 0; 231 232 if (!node) 233 return -ENODEV; 234 235 cinfo = devm_kzalloc(&pdev->dev, sizeof(*cinfo), GFP_KERNEL); 236 if (!cinfo) 237 return -ENOMEM; 238 239 cinfo->iobase = of_iomap(node, 0); 240 cinfo->dev = &pdev->dev; 241 pm_runtime_enable(cinfo->dev); 242 pm_runtime_irq_safe(cinfo->dev); 243 244 pm_runtime_get_sync(cinfo->dev); 245 atl_write(cinfo, DRA7_ATL_PCLKMUX_REG(0), DRA7_ATL_PCLKMUX); 246 247 for (i = 0; i < DRA7_ATL_INSTANCES; i++) { 248 struct device_node *cfg_node; 249 char prop[5]; 250 struct dra7_atl_desc *cdesc; 251 struct of_phandle_args clkspec; 252 struct clk *clk; 253 int rc; 254 255 rc = of_parse_phandle_with_args(node, "ti,provided-clocks", 256 NULL, i, &clkspec); 257 258 if (rc) { 259 pr_err("%s: failed to lookup atl clock %d\n", __func__, 260 i); 261 return -EINVAL; 262 } 263 264 clk = of_clk_get_from_provider(&clkspec); 265 if (IS_ERR(clk)) { 266 pr_err("%s: failed to get atl clock %d from provider\n", 267 __func__, i); 268 return PTR_ERR(clk); 269 } 270 271 cdesc = to_atl_desc(__clk_get_hw(clk)); 272 cdesc->cinfo = cinfo; 273 cdesc->id = i; 274 275 /* Get configuration for the ATL instances */ 276 snprintf(prop, sizeof(prop), "atl%u", i); 277 cfg_node = of_get_child_by_name(node, prop); 278 if (cfg_node) { 279 ret = of_property_read_u32(cfg_node, "bws", 280 &cdesc->bws); 281 ret |= of_property_read_u32(cfg_node, "aws", 282 &cdesc->aws); 283 if (!ret) { 284 cdesc->valid = true; 285 atl_write(cinfo, DRA7_ATL_BWSMUX_REG(i), 286 cdesc->bws); 287 atl_write(cinfo, DRA7_ATL_AWSMUX_REG(i), 288 cdesc->aws); 289 } 290 of_node_put(cfg_node); 291 } 292 293 cdesc->probed = true; 294 /* 295 * Enable the clock if it has been asked prior to loading the 296 * hw driver 297 */ 298 if (cdesc->enabled) 299 atl_clk_enable(__clk_get_hw(clk)); 300 } 301 pm_runtime_put_sync(cinfo->dev); 302 303 return ret; 304 } 305 306 static const struct of_device_id of_dra7_atl_clk_match_tbl[] = { 307 { .compatible = "ti,dra7-atl", }, 308 {}, 309 }; 310 311 static struct platform_driver dra7_atl_clk_driver = { 312 .driver = { 313 .name = "dra7-atl", 314 .suppress_bind_attrs = true, 315 .of_match_table = of_dra7_atl_clk_match_tbl, 316 }, 317 .probe = of_dra7_atl_clk_probe, 318 }; 319 builtin_platform_driver(dra7_atl_clk_driver); 320