1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * Memory controller driver for ARM PrimeCell PL172 4 * PrimeCell MultiPort Memory Controller (PL172) 5 * 6 * Copyright (C) 2015 Joachim Eastwood <manabian@gmail.com> 7 * 8 * Based on: 9 * TI AEMIF driver, Copyright (C) 2010 - 2013 Texas Instruments Inc. 10 */ 11 12 #include <linux/amba/bus.h> 13 #include <linux/clk.h> 14 #include <linux/device.h> 15 #include <linux/err.h> 16 #include <linux/init.h> 17 #include <linux/io.h> 18 #include <linux/kernel.h> 19 #include <linux/module.h> 20 #include <linux/of.h> 21 #include <linux/of_platform.h> 22 #include <linux/time.h> 23 24 #define MPMC_STATIC_CFG(n) (0x200 + 0x20 * (n)) 25 #define MPMC_STATIC_CFG_MW_8BIT 0x0 26 #define MPMC_STATIC_CFG_MW_16BIT 0x1 27 #define MPMC_STATIC_CFG_MW_32BIT 0x2 28 #define MPMC_STATIC_CFG_PM BIT(3) 29 #define MPMC_STATIC_CFG_PC BIT(6) 30 #define MPMC_STATIC_CFG_PB BIT(7) 31 #define MPMC_STATIC_CFG_EW BIT(8) 32 #define MPMC_STATIC_CFG_B BIT(19) 33 #define MPMC_STATIC_CFG_P BIT(20) 34 #define MPMC_STATIC_WAIT_WEN(n) (0x204 + 0x20 * (n)) 35 #define MPMC_STATIC_WAIT_WEN_MAX 0x0f 36 #define MPMC_STATIC_WAIT_OEN(n) (0x208 + 0x20 * (n)) 37 #define MPMC_STATIC_WAIT_OEN_MAX 0x0f 38 #define MPMC_STATIC_WAIT_RD(n) (0x20c + 0x20 * (n)) 39 #define MPMC_STATIC_WAIT_RD_MAX 0x1f 40 #define MPMC_STATIC_WAIT_PAGE(n) (0x210 + 0x20 * (n)) 41 #define MPMC_STATIC_WAIT_PAGE_MAX 0x1f 42 #define MPMC_STATIC_WAIT_WR(n) (0x214 + 0x20 * (n)) 43 #define MPMC_STATIC_WAIT_WR_MAX 0x1f 44 #define MPMC_STATIC_WAIT_TURN(n) (0x218 + 0x20 * (n)) 45 #define MPMC_STATIC_WAIT_TURN_MAX 0x0f 46 47 /* Maximum number of static chip selects */ 48 #define PL172_MAX_CS 4 49 50 struct pl172_data { 51 void __iomem *base; 52 unsigned long rate; 53 struct clk *clk; 54 }; 55 56 static int pl172_timing_prop(struct amba_device *adev, 57 const struct device_node *np, const char *name, 58 u32 reg_offset, u32 max, int start) 59 { 60 struct pl172_data *pl172 = amba_get_drvdata(adev); 61 int cycles; 62 u32 val; 63 64 if (!of_property_read_u32(np, name, &val)) { 65 cycles = DIV_ROUND_UP(val * pl172->rate, NSEC_PER_MSEC) - start; 66 if (cycles < 0) { 67 cycles = 0; 68 } else if (cycles > max) { 69 dev_err(&adev->dev, "%s timing too tight\n", name); 70 return -EINVAL; 71 } 72 73 writel(cycles, pl172->base + reg_offset); 74 } 75 76 dev_dbg(&adev->dev, "%s: %u cycle(s)\n", name, start + 77 readl(pl172->base + reg_offset)); 78 79 return 0; 80 } 81 82 static int pl172_setup_static(struct amba_device *adev, 83 struct device_node *np, u32 cs) 84 { 85 struct pl172_data *pl172 = amba_get_drvdata(adev); 86 u32 cfg; 87 int ret; 88 89 /* MPMC static memory configuration */ 90 if (!of_property_read_u32(np, "mpmc,memory-width", &cfg)) { 91 if (cfg == 8) { 92 cfg = MPMC_STATIC_CFG_MW_8BIT; 93 } else if (cfg == 16) { 94 cfg = MPMC_STATIC_CFG_MW_16BIT; 95 } else if (cfg == 32) { 96 cfg = MPMC_STATIC_CFG_MW_32BIT; 97 } else { 98 dev_err(&adev->dev, "invalid memory width cs%u\n", cs); 99 return -EINVAL; 100 } 101 } else { 102 dev_err(&adev->dev, "memory-width property required\n"); 103 return -EINVAL; 104 } 105 106 if (of_property_read_bool(np, "mpmc,async-page-mode")) 107 cfg |= MPMC_STATIC_CFG_PM; 108 109 if (of_property_read_bool(np, "mpmc,cs-active-high")) 110 cfg |= MPMC_STATIC_CFG_PC; 111 112 if (of_property_read_bool(np, "mpmc,byte-lane-low")) 113 cfg |= MPMC_STATIC_CFG_PB; 114 115 if (of_property_read_bool(np, "mpmc,extended-wait")) 116 cfg |= MPMC_STATIC_CFG_EW; 117 118 if (amba_part(adev) == 0x172 && 119 of_property_read_bool(np, "mpmc,buffer-enable")) 120 cfg |= MPMC_STATIC_CFG_B; 121 122 if (of_property_read_bool(np, "mpmc,write-protect")) 123 cfg |= MPMC_STATIC_CFG_P; 124 125 writel(cfg, pl172->base + MPMC_STATIC_CFG(cs)); 126 dev_dbg(&adev->dev, "mpmc static config cs%u: 0x%08x\n", cs, cfg); 127 128 /* MPMC static memory timing */ 129 ret = pl172_timing_prop(adev, np, "mpmc,write-enable-delay", 130 MPMC_STATIC_WAIT_WEN(cs), 131 MPMC_STATIC_WAIT_WEN_MAX, 1); 132 if (ret) 133 goto fail; 134 135 ret = pl172_timing_prop(adev, np, "mpmc,output-enable-delay", 136 MPMC_STATIC_WAIT_OEN(cs), 137 MPMC_STATIC_WAIT_OEN_MAX, 0); 138 if (ret) 139 goto fail; 140 141 ret = pl172_timing_prop(adev, np, "mpmc,read-access-delay", 142 MPMC_STATIC_WAIT_RD(cs), 143 MPMC_STATIC_WAIT_RD_MAX, 1); 144 if (ret) 145 goto fail; 146 147 ret = pl172_timing_prop(adev, np, "mpmc,page-mode-read-delay", 148 MPMC_STATIC_WAIT_PAGE(cs), 149 MPMC_STATIC_WAIT_PAGE_MAX, 1); 150 if (ret) 151 goto fail; 152 153 ret = pl172_timing_prop(adev, np, "mpmc,write-access-delay", 154 MPMC_STATIC_WAIT_WR(cs), 155 MPMC_STATIC_WAIT_WR_MAX, 2); 156 if (ret) 157 goto fail; 158 159 ret = pl172_timing_prop(adev, np, "mpmc,turn-round-delay", 160 MPMC_STATIC_WAIT_TURN(cs), 161 MPMC_STATIC_WAIT_TURN_MAX, 1); 162 if (ret) 163 goto fail; 164 165 return 0; 166 fail: 167 dev_err(&adev->dev, "failed to configure cs%u\n", cs); 168 return ret; 169 } 170 171 static int pl172_parse_cs_config(struct amba_device *adev, 172 struct device_node *np) 173 { 174 u32 cs; 175 176 if (!of_property_read_u32(np, "mpmc,cs", &cs)) { 177 if (cs >= PL172_MAX_CS) { 178 dev_err(&adev->dev, "cs%u invalid\n", cs); 179 return -EINVAL; 180 } 181 182 return pl172_setup_static(adev, np, cs); 183 } 184 185 dev_err(&adev->dev, "cs property required\n"); 186 187 return -EINVAL; 188 } 189 190 static const char * const pl172_revisions[] = {"r1", "r2", "r2p3", "r2p4"}; 191 static const char * const pl175_revisions[] = {"r1"}; 192 static const char * const pl176_revisions[] = {"r0"}; 193 194 static int pl172_probe(struct amba_device *adev, const struct amba_id *id) 195 { 196 struct device_node *child_np, *np = adev->dev.of_node; 197 struct device *dev = &adev->dev; 198 static const char *rev = "?"; 199 struct pl172_data *pl172; 200 int ret; 201 202 if (amba_part(adev) == 0x172) { 203 if (amba_rev(adev) < ARRAY_SIZE(pl172_revisions)) 204 rev = pl172_revisions[amba_rev(adev)]; 205 } else if (amba_part(adev) == 0x175) { 206 if (amba_rev(adev) < ARRAY_SIZE(pl175_revisions)) 207 rev = pl175_revisions[amba_rev(adev)]; 208 } else if (amba_part(adev) == 0x176) { 209 if (amba_rev(adev) < ARRAY_SIZE(pl176_revisions)) 210 rev = pl176_revisions[amba_rev(adev)]; 211 } 212 213 dev_info(dev, "ARM PL%x revision %s\n", amba_part(adev), rev); 214 215 pl172 = devm_kzalloc(dev, sizeof(*pl172), GFP_KERNEL); 216 if (!pl172) 217 return -ENOMEM; 218 219 pl172->clk = devm_clk_get(dev, "mpmcclk"); 220 if (IS_ERR(pl172->clk)) { 221 dev_err(dev, "no mpmcclk provided clock\n"); 222 return PTR_ERR(pl172->clk); 223 } 224 225 ret = clk_prepare_enable(pl172->clk); 226 if (ret) { 227 dev_err(dev, "unable to mpmcclk enable clock\n"); 228 return ret; 229 } 230 231 pl172->rate = clk_get_rate(pl172->clk) / MSEC_PER_SEC; 232 if (!pl172->rate) { 233 dev_err(dev, "unable to get mpmcclk clock rate\n"); 234 ret = -EINVAL; 235 goto err_clk_enable; 236 } 237 238 ret = amba_request_regions(adev, NULL); 239 if (ret) { 240 dev_err(dev, "unable to request AMBA regions\n"); 241 goto err_clk_enable; 242 } 243 244 pl172->base = devm_ioremap(dev, adev->res.start, 245 resource_size(&adev->res)); 246 if (!pl172->base) { 247 dev_err(dev, "ioremap failed\n"); 248 ret = -ENOMEM; 249 goto err_no_ioremap; 250 } 251 252 amba_set_drvdata(adev, pl172); 253 254 /* 255 * Loop through each child node, which represent a chip select, and 256 * configure parameters and timing. If successful; populate devices 257 * under that node. 258 */ 259 for_each_available_child_of_node(np, child_np) { 260 ret = pl172_parse_cs_config(adev, child_np); 261 if (ret) 262 continue; 263 264 of_platform_populate(child_np, NULL, NULL, dev); 265 } 266 267 return 0; 268 269 err_no_ioremap: 270 amba_release_regions(adev); 271 err_clk_enable: 272 clk_disable_unprepare(pl172->clk); 273 return ret; 274 } 275 276 static int pl172_remove(struct amba_device *adev) 277 { 278 struct pl172_data *pl172 = amba_get_drvdata(adev); 279 280 clk_disable_unprepare(pl172->clk); 281 amba_release_regions(adev); 282 283 return 0; 284 } 285 286 static const struct amba_id pl172_ids[] = { 287 /* PrimeCell MPMC PL172, EMC found on NXP LPC18xx and LPC43xx */ 288 { 289 .id = 0x07041172, 290 .mask = 0x3f0fffff, 291 }, 292 /* PrimeCell MPMC PL175, EMC found on NXP LPC32xx */ 293 { 294 .id = 0x07041175, 295 .mask = 0x3f0fffff, 296 }, 297 /* PrimeCell MPMC PL176 */ 298 { 299 .id = 0x89041176, 300 .mask = 0xff0fffff, 301 }, 302 { 0, 0 }, 303 }; 304 MODULE_DEVICE_TABLE(amba, pl172_ids); 305 306 static struct amba_driver pl172_driver = { 307 .drv = { 308 .name = "memory-pl172", 309 }, 310 .probe = pl172_probe, 311 .remove = pl172_remove, 312 .id_table = pl172_ids, 313 }; 314 module_amba_driver(pl172_driver); 315 316 MODULE_AUTHOR("Joachim Eastwood <manabian@gmail.com>"); 317 MODULE_DESCRIPTION("PL172 Memory Controller Driver"); 318 MODULE_LICENSE("GPL v2"); 319