Aneesh V | 7ec9445 | 2012-04-27 17:54:05 +0530 | [diff] [blame^] | 1 | /* |
| 2 | * EMIF driver |
| 3 | * |
| 4 | * Copyright (C) 2012 Texas Instruments, Inc. |
| 5 | * |
| 6 | * Aneesh V <aneesh@ti.com> |
| 7 | * Santosh Shilimkar <santosh.shilimkar@ti.com> |
| 8 | * |
| 9 | * This program is free software; you can redistribute it and/or modify |
| 10 | * it under the terms of the GNU General Public License version 2 as |
| 11 | * published by the Free Software Foundation. |
| 12 | */ |
| 13 | #include <linux/kernel.h> |
| 14 | #include <linux/reboot.h> |
| 15 | #include <linux/platform_data/emif_plat.h> |
| 16 | #include <linux/io.h> |
| 17 | #include <linux/device.h> |
| 18 | #include <linux/platform_device.h> |
| 19 | #include <linux/interrupt.h> |
| 20 | #include <linux/slab.h> |
| 21 | #include <linux/seq_file.h> |
| 22 | #include <linux/module.h> |
| 23 | #include <linux/list.h> |
| 24 | #include <memory/jedec_ddr.h> |
| 25 | #include "emif.h" |
| 26 | |
| 27 | /** |
| 28 | * struct emif_data - Per device static data for driver's use |
| 29 | * @duplicate: Whether the DDR devices attached to this EMIF |
| 30 | * instance are exactly same as that on EMIF1. In |
| 31 | * this case we can save some memory and processing |
| 32 | * @temperature_level: Maximum temperature of LPDDR2 devices attached |
| 33 | * to this EMIF - read from MR4 register. If there |
| 34 | * are two devices attached to this EMIF, this |
| 35 | * value is the maximum of the two temperature |
| 36 | * levels. |
| 37 | * @node: node in the device list |
| 38 | * @base: base address of memory-mapped IO registers. |
| 39 | * @dev: device pointer. |
| 40 | * @plat_data: Pointer to saved platform data. |
| 41 | */ |
| 42 | struct emif_data { |
| 43 | u8 duplicate; |
| 44 | u8 temperature_level; |
| 45 | struct list_head node; |
| 46 | void __iomem *base; |
| 47 | struct device *dev; |
| 48 | struct emif_platform_data *plat_data; |
| 49 | }; |
| 50 | |
| 51 | static struct emif_data *emif1; |
| 52 | static LIST_HEAD(device_list); |
| 53 | |
| 54 | static void get_default_timings(struct emif_data *emif) |
| 55 | { |
| 56 | struct emif_platform_data *pd = emif->plat_data; |
| 57 | |
| 58 | pd->timings = lpddr2_jedec_timings; |
| 59 | pd->timings_arr_size = ARRAY_SIZE(lpddr2_jedec_timings); |
| 60 | |
| 61 | dev_warn(emif->dev, "%s: using default timings\n", __func__); |
| 62 | } |
| 63 | |
| 64 | static int is_dev_data_valid(u32 type, u32 density, u32 io_width, u32 phy_type, |
| 65 | u32 ip_rev, struct device *dev) |
| 66 | { |
| 67 | int valid; |
| 68 | |
| 69 | valid = (type == DDR_TYPE_LPDDR2_S4 || |
| 70 | type == DDR_TYPE_LPDDR2_S2) |
| 71 | && (density >= DDR_DENSITY_64Mb |
| 72 | && density <= DDR_DENSITY_8Gb) |
| 73 | && (io_width >= DDR_IO_WIDTH_8 |
| 74 | && io_width <= DDR_IO_WIDTH_32); |
| 75 | |
| 76 | /* Combinations of EMIF and PHY revisions that we support today */ |
| 77 | switch (ip_rev) { |
| 78 | case EMIF_4D: |
| 79 | valid = valid && (phy_type == EMIF_PHY_TYPE_ATTILAPHY); |
| 80 | break; |
| 81 | case EMIF_4D5: |
| 82 | valid = valid && (phy_type == EMIF_PHY_TYPE_INTELLIPHY); |
| 83 | break; |
| 84 | default: |
| 85 | valid = 0; |
| 86 | } |
| 87 | |
| 88 | if (!valid) |
| 89 | dev_err(dev, "%s: invalid DDR details\n", __func__); |
| 90 | return valid; |
| 91 | } |
| 92 | |
| 93 | static int is_custom_config_valid(struct emif_custom_configs *cust_cfgs, |
| 94 | struct device *dev) |
| 95 | { |
| 96 | int valid = 1; |
| 97 | |
| 98 | if ((cust_cfgs->mask & EMIF_CUSTOM_CONFIG_LPMODE) && |
| 99 | (cust_cfgs->lpmode != EMIF_LP_MODE_DISABLE)) |
| 100 | valid = cust_cfgs->lpmode_freq_threshold && |
| 101 | cust_cfgs->lpmode_timeout_performance && |
| 102 | cust_cfgs->lpmode_timeout_power; |
| 103 | |
| 104 | if (cust_cfgs->mask & EMIF_CUSTOM_CONFIG_TEMP_ALERT_POLL_INTERVAL) |
| 105 | valid = valid && cust_cfgs->temp_alert_poll_interval_ms; |
| 106 | |
| 107 | if (!valid) |
| 108 | dev_warn(dev, "%s: invalid custom configs\n", __func__); |
| 109 | |
| 110 | return valid; |
| 111 | } |
| 112 | |
| 113 | static struct emif_data *__init_or_module get_device_details( |
| 114 | struct platform_device *pdev) |
| 115 | { |
| 116 | u32 size; |
| 117 | struct emif_data *emif = NULL; |
| 118 | struct ddr_device_info *dev_info; |
| 119 | struct emif_custom_configs *cust_cfgs; |
| 120 | struct emif_platform_data *pd; |
| 121 | struct device *dev; |
| 122 | void *temp; |
| 123 | |
| 124 | pd = pdev->dev.platform_data; |
| 125 | dev = &pdev->dev; |
| 126 | |
| 127 | if (!(pd && pd->device_info && is_dev_data_valid(pd->device_info->type, |
| 128 | pd->device_info->density, pd->device_info->io_width, |
| 129 | pd->phy_type, pd->ip_rev, dev))) { |
| 130 | dev_err(dev, "%s: invalid device data\n", __func__); |
| 131 | goto error; |
| 132 | } |
| 133 | |
| 134 | emif = devm_kzalloc(dev, sizeof(*emif), GFP_KERNEL); |
| 135 | temp = devm_kzalloc(dev, sizeof(*pd), GFP_KERNEL); |
| 136 | dev_info = devm_kzalloc(dev, sizeof(*dev_info), GFP_KERNEL); |
| 137 | |
| 138 | if (!emif || !pd || !dev_info) { |
| 139 | dev_err(dev, "%s:%d: allocation error\n", __func__, __LINE__); |
| 140 | goto error; |
| 141 | } |
| 142 | |
| 143 | memcpy(temp, pd, sizeof(*pd)); |
| 144 | pd = temp; |
| 145 | memcpy(dev_info, pd->device_info, sizeof(*dev_info)); |
| 146 | |
| 147 | pd->device_info = dev_info; |
| 148 | emif->plat_data = pd; |
| 149 | emif->dev = dev; |
| 150 | emif->temperature_level = SDRAM_TEMP_NOMINAL; |
| 151 | |
| 152 | /* |
| 153 | * For EMIF instances other than EMIF1 see if the devices connected |
| 154 | * are exactly same as on EMIF1(which is typically the case). If so, |
| 155 | * mark it as a duplicate of EMIF1 and skip copying timings data. |
| 156 | * This will save some memory and some computation later. |
| 157 | */ |
| 158 | emif->duplicate = emif1 && (memcmp(dev_info, |
| 159 | emif1->plat_data->device_info, |
| 160 | sizeof(struct ddr_device_info)) == 0); |
| 161 | |
| 162 | if (emif->duplicate) { |
| 163 | pd->timings = NULL; |
| 164 | pd->min_tck = NULL; |
| 165 | goto out; |
| 166 | } else if (emif1) { |
| 167 | dev_warn(emif->dev, "%s: Non-symmetric DDR geometry\n", |
| 168 | __func__); |
| 169 | } |
| 170 | |
| 171 | /* |
| 172 | * Copy custom configs - ignore allocation error, if any, as |
| 173 | * custom_configs is not very critical |
| 174 | */ |
| 175 | cust_cfgs = pd->custom_configs; |
| 176 | if (cust_cfgs && is_custom_config_valid(cust_cfgs, dev)) { |
| 177 | temp = devm_kzalloc(dev, sizeof(*cust_cfgs), GFP_KERNEL); |
| 178 | if (temp) |
| 179 | memcpy(temp, cust_cfgs, sizeof(*cust_cfgs)); |
| 180 | else |
| 181 | dev_warn(dev, "%s:%d: allocation error\n", __func__, |
| 182 | __LINE__); |
| 183 | pd->custom_configs = temp; |
| 184 | } |
| 185 | |
| 186 | /* |
| 187 | * Copy timings and min-tck values from platform data. If it is not |
| 188 | * available or if memory allocation fails, use JEDEC defaults |
| 189 | */ |
| 190 | size = sizeof(struct lpddr2_timings) * pd->timings_arr_size; |
| 191 | if (pd->timings) { |
| 192 | temp = devm_kzalloc(dev, size, GFP_KERNEL); |
| 193 | if (temp) { |
| 194 | memcpy(temp, pd->timings, sizeof(*pd->timings)); |
| 195 | pd->timings = temp; |
| 196 | } else { |
| 197 | dev_warn(dev, "%s:%d: allocation error\n", __func__, |
| 198 | __LINE__); |
| 199 | get_default_timings(emif); |
| 200 | } |
| 201 | } else { |
| 202 | get_default_timings(emif); |
| 203 | } |
| 204 | |
| 205 | if (pd->min_tck) { |
| 206 | temp = devm_kzalloc(dev, sizeof(*pd->min_tck), GFP_KERNEL); |
| 207 | if (temp) { |
| 208 | memcpy(temp, pd->min_tck, sizeof(*pd->min_tck)); |
| 209 | pd->min_tck = temp; |
| 210 | } else { |
| 211 | dev_warn(dev, "%s:%d: allocation error\n", __func__, |
| 212 | __LINE__); |
| 213 | pd->min_tck = &lpddr2_jedec_min_tck; |
| 214 | } |
| 215 | } else { |
| 216 | pd->min_tck = &lpddr2_jedec_min_tck; |
| 217 | } |
| 218 | |
| 219 | out: |
| 220 | return emif; |
| 221 | |
| 222 | error: |
| 223 | return NULL; |
| 224 | } |
| 225 | |
| 226 | static int __init_or_module emif_probe(struct platform_device *pdev) |
| 227 | { |
| 228 | struct emif_data *emif; |
| 229 | struct resource *res; |
| 230 | |
| 231 | emif = get_device_details(pdev); |
| 232 | if (!emif) { |
| 233 | pr_err("%s: error getting device data\n", __func__); |
| 234 | goto error; |
| 235 | } |
| 236 | |
| 237 | if (!emif1) |
| 238 | emif1 = emif; |
| 239 | |
| 240 | list_add(&emif->node, &device_list); |
| 241 | |
| 242 | /* Save pointers to each other in emif and device structures */ |
| 243 | emif->dev = &pdev->dev; |
| 244 | platform_set_drvdata(pdev, emif); |
| 245 | |
| 246 | res = platform_get_resource(pdev, IORESOURCE_MEM, 0); |
| 247 | if (!res) { |
| 248 | dev_err(emif->dev, "%s: error getting memory resource\n", |
| 249 | __func__); |
| 250 | goto error; |
| 251 | } |
| 252 | |
| 253 | emif->base = devm_request_and_ioremap(emif->dev, res); |
| 254 | if (!emif->base) { |
| 255 | dev_err(emif->dev, "%s: devm_request_and_ioremap() failed\n", |
| 256 | __func__); |
| 257 | goto error; |
| 258 | } |
| 259 | |
| 260 | dev_info(&pdev->dev, "%s: device configured with addr = %p\n", |
| 261 | __func__, emif->base); |
| 262 | |
| 263 | return 0; |
| 264 | error: |
| 265 | return -ENODEV; |
| 266 | } |
| 267 | |
| 268 | static struct platform_driver emif_driver = { |
| 269 | .driver = { |
| 270 | .name = "emif", |
| 271 | }, |
| 272 | }; |
| 273 | |
| 274 | static int __init_or_module emif_register(void) |
| 275 | { |
| 276 | return platform_driver_probe(&emif_driver, emif_probe); |
| 277 | } |
| 278 | |
| 279 | static void __exit emif_unregister(void) |
| 280 | { |
| 281 | platform_driver_unregister(&emif_driver); |
| 282 | } |
| 283 | |
| 284 | module_init(emif_register); |
| 285 | module_exit(emif_unregister); |
| 286 | MODULE_DESCRIPTION("TI EMIF SDRAM Controller Driver"); |
| 287 | MODULE_LICENSE("GPL"); |
| 288 | MODULE_ALIAS("platform:emif"); |
| 289 | MODULE_AUTHOR("Texas Instruments Inc"); |