diff options
| author | Linus Torvalds <torvalds@linux-foundation.org> | 2008-10-23 13:20:36 -0400 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2008-10-23 13:20:36 -0400 |
| commit | 765426e8ee4c0ab2bc9d44951f4865b8494cdbd0 (patch) | |
| tree | 2b46ab8953eff175c8d3474a9754c1ab1394e4de /drivers/idle/i7300_idle.c | |
| parent | 36ec891895020f3bc9953c8b11d079c6d77d76bd (diff) | |
| parent | 898b054f3eec5921320ae8614b5bdd7b07ea5b43 (diff) | |
Merge branch 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux-acpi-2.6
* 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux-acpi-2.6: (123 commits)
dock: make dock driver not a module
ACPI: fix ia64 build warning
ACPI: hack around sysfs warning with link order
ACPI suspend: fix build warning when CONFIG_ACPI_SLEEP=n
intel_menlo: fix build warning
panasonic-laptop: fix build
ACPICA: Update version to 20080926
ACPICA: Add support for zero-length buffer-to-string conversions
ACPICA: New: Validation for predefined ACPI methods/objects
ACPICA: Fix for implicit return compatibility
ACPICA: Fixed a couple memory leaks associated with "implicit return"
ACPICA: Optimize buffer allocation procedure
ACPICA: Fix possible memory leak, error exit path
ACPICA: Fix fault after mem allocation failure in AML parser
ACPICA: Remove unused ACPI register bit definition
ACPICA: Update version to 20080829
ACPICA: Fix possible memory leak in acpi_ns_get_external_pathname
ACPICA: Cleanup for internal Reference Object
ACPICA: Update comments - no functional changes
ACPICA: Update for Reference ACPI_OPERAND_OBJECT
...
Diffstat (limited to 'drivers/idle/i7300_idle.c')
| -rw-r--r-- | drivers/idle/i7300_idle.c | 674 |
1 files changed, 674 insertions, 0 deletions
diff --git a/drivers/idle/i7300_idle.c b/drivers/idle/i7300_idle.c new file mode 100644 index 00000000000..59d1bbc3cd3 --- /dev/null +++ b/drivers/idle/i7300_idle.c | |||
| @@ -0,0 +1,674 @@ | |||
| 1 | /* | ||
| 2 | * (C) Copyright 2008 Intel Corporation | ||
| 3 | * Authors: | ||
| 4 | * Andy Henroid <andrew.d.henroid@intel.com> | ||
| 5 | * Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> | ||
| 6 | */ | ||
| 7 | |||
| 8 | /* | ||
| 9 | * Save DIMM power on Intel 7300-based platforms when all CPUs/cores | ||
| 10 | * are idle, using the DIMM thermal throttling capability. | ||
| 11 | * | ||
| 12 | * This driver depends on the Intel integrated DMA controller (I/O AT). | ||
| 13 | * If the driver for I/O AT (drivers/dma/ioatdma*) is also enabled, | ||
| 14 | * this driver should work cooperatively. | ||
| 15 | */ | ||
| 16 | |||
| 17 | /* #define DEBUG */ | ||
| 18 | |||
| 19 | #include <linux/module.h> | ||
| 20 | #include <linux/pci.h> | ||
| 21 | #include <linux/sched.h> | ||
| 22 | #include <linux/notifier.h> | ||
| 23 | #include <linux/cpumask.h> | ||
| 24 | #include <linux/ktime.h> | ||
| 25 | #include <linux/delay.h> | ||
| 26 | #include <linux/debugfs.h> | ||
| 27 | #include <linux/stop_machine.h> | ||
| 28 | |||
| 29 | #include <asm/idle.h> | ||
| 30 | |||
| 31 | #include "../dma/ioatdma_hw.h" | ||
| 32 | #include "../dma/ioatdma_registers.h" | ||
| 33 | |||
| 34 | #define I7300_IDLE_DRIVER_VERSION "1.55" | ||
| 35 | #define I7300_PRINT "i7300_idle:" | ||
| 36 | |||
| 37 | static int debug; | ||
| 38 | module_param_named(debug, debug, uint, 0644); | ||
| 39 | MODULE_PARM_DESC(debug, "Enable debug printks in this driver"); | ||
| 40 | |||
| 41 | #define dprintk(fmt, arg...) \ | ||
| 42 | do { if (debug) printk(KERN_INFO I7300_PRINT fmt, ##arg); } while (0) | ||
| 43 | |||
| 44 | /* | ||
| 45 | * Value to set THRTLOW to when initiating throttling | ||
| 46 | * 0 = No throttling | ||
| 47 | * 1 = Throttle when > 4 activations per eval window (Maximum throttling) | ||
| 48 | * 2 = Throttle when > 8 activations | ||
| 49 | * 168 = Throttle when > 168 activations (Minimum throttling) | ||
| 50 | */ | ||
| 51 | #define MAX_THRTLWLIMIT 168 | ||
| 52 | static uint i7300_idle_thrtlowlm = 1; | ||
| 53 | module_param_named(thrtlwlimit, i7300_idle_thrtlowlm, uint, 0644); | ||
| 54 | MODULE_PARM_DESC(thrtlwlimit, | ||
| 55 | "Value for THRTLOWLM activation field " | ||
| 56 | "(0 = disable throttle, 1 = Max throttle, 168 = Min throttle)"); | ||
| 57 | |||
| 58 | /* | ||
| 59 | * simple invocation and duration statistics | ||
| 60 | */ | ||
| 61 | static unsigned long total_starts; | ||
| 62 | static unsigned long total_us; | ||
| 63 | |||
| 64 | #ifdef DEBUG | ||
| 65 | static unsigned long past_skip; | ||
| 66 | #endif | ||
| 67 | |||
| 68 | static struct pci_dev *fbd_dev; | ||
| 69 | |||
| 70 | static spinlock_t i7300_idle_lock; | ||
| 71 | static int i7300_idle_active; | ||
| 72 | |||
| 73 | static u8 i7300_idle_thrtctl_saved; | ||
| 74 | static u8 i7300_idle_thrtlow_saved; | ||
| 75 | static u32 i7300_idle_mc_saved; | ||
| 76 | |||
| 77 | static cpumask_t idle_cpumask; | ||
| 78 | static ktime_t start_ktime; | ||
| 79 | static unsigned long avg_idle_us; | ||
| 80 | |||
| 81 | static struct dentry *debugfs_dir; | ||
| 82 | |||
| 83 | /* Begin: I/O AT Helper routines */ | ||
| 84 | |||
| 85 | #define IOAT_CHANBASE(ioat_ctl, chan) (ioat_ctl + 0x80 + 0x80 * chan) | ||
| 86 | /* Snoop control (disable snoops when coherency is not important) */ | ||
| 87 | #define IOAT_DESC_SADDR_SNP_CTL (1UL << 1) | ||
| 88 | #define IOAT_DESC_DADDR_SNP_CTL (1UL << 2) | ||
| 89 | |||
| 90 | static struct pci_dev *ioat_dev; | ||
| 91 | static struct ioat_dma_descriptor *ioat_desc; /* I/O AT desc & data (1 page) */ | ||
| 92 | static unsigned long ioat_desc_phys; | ||
| 93 | static u8 *ioat_iomap; /* I/O AT memory-mapped control regs (aka CB_BAR) */ | ||
| 94 | static u8 *ioat_chanbase; | ||
| 95 | |||
| 96 | /* Start I/O AT memory copy */ | ||
| 97 | static int i7300_idle_ioat_start(void) | ||
| 98 | { | ||
| 99 | u32 err; | ||
| 100 | /* Clear error (due to circular descriptor pointer) */ | ||
| 101 | err = readl(ioat_chanbase + IOAT_CHANERR_OFFSET); | ||
| 102 | if (err) | ||
| 103 | writel(err, ioat_chanbase + IOAT_CHANERR_OFFSET); | ||
| 104 | |||
| 105 | writeb(IOAT_CHANCMD_START, ioat_chanbase + IOAT1_CHANCMD_OFFSET); | ||
| 106 | return 0; | ||
| 107 | } | ||
| 108 | |||
| 109 | /* Stop I/O AT memory copy */ | ||
| 110 | static void i7300_idle_ioat_stop(void) | ||
| 111 | { | ||
| 112 | int i; | ||
| 113 | u8 sts; | ||
| 114 | |||
| 115 | for (i = 0; i < 5; i++) { | ||
| 116 | writeb(IOAT_CHANCMD_RESET, | ||
| 117 | ioat_chanbase + IOAT1_CHANCMD_OFFSET); | ||
| 118 | |||
| 119 | udelay(10); | ||
| 120 | |||
| 121 | sts = readq(ioat_chanbase + IOAT1_CHANSTS_OFFSET) & | ||
| 122 | IOAT_CHANSTS_DMA_TRANSFER_STATUS; | ||
| 123 | |||
| 124 | if (sts != IOAT_CHANSTS_DMA_TRANSFER_STATUS_ACTIVE) | ||
| 125 | break; | ||
| 126 | |||
| 127 | } | ||
| 128 | |||
| 129 | if (i == 5) | ||
| 130 | dprintk("failed to suspend+reset I/O AT after 5 retries\n"); | ||
| 131 | |||
| 132 | } | ||
| 133 | |||
| 134 | /* Test I/O AT by copying 1024 byte from 2k to 1k */ | ||
| 135 | static int __init i7300_idle_ioat_selftest(u8 *ctl, | ||
| 136 | struct ioat_dma_descriptor *desc, unsigned long desc_phys) | ||
| 137 | { | ||
| 138 | u64 chan_sts; | ||
| 139 | |||
| 140 | memset(desc, 0, 2048); | ||
| 141 | memset((u8 *) desc + 2048, 0xab, 1024); | ||
| 142 | |||
| 143 | desc[0].size = 1024; | ||
| 144 | desc[0].ctl = 0; | ||
| 145 | desc[0].src_addr = desc_phys + 2048; | ||
| 146 | desc[0].dst_addr = desc_phys + 1024; | ||
| 147 | desc[0].next = 0; | ||
| 148 | |||
| 149 | writeb(IOAT_CHANCMD_RESET, ioat_chanbase + IOAT1_CHANCMD_OFFSET); | ||
| 150 | writeb(IOAT_CHANCMD_START, ioat_chanbase + IOAT1_CHANCMD_OFFSET); | ||
| 151 | |||
| 152 | udelay(1000); | ||
| 153 | |||
| 154 | chan_sts = readq(ioat_chanbase + IOAT1_CHANSTS_OFFSET) & | ||
| 155 | IOAT_CHANSTS_DMA_TRANSFER_STATUS; | ||
| 156 | |||
| 157 | if (chan_sts != IOAT_CHANSTS_DMA_TRANSFER_STATUS_DONE) { | ||
| 158 | /* Not complete, reset the channel */ | ||
| 159 | writeb(IOAT_CHANCMD_RESET, | ||
| 160 | ioat_chanbase + IOAT1_CHANCMD_OFFSET); | ||
| 161 | return -1; | ||
| 162 | } | ||
| 163 | |||
| 164 | if (*(u32 *) ((u8 *) desc + 3068) != 0xabababab || | ||
| 165 | *(u32 *) ((u8 *) desc + 2044) != 0xabababab) { | ||
| 166 | dprintk("Data values src 0x%x, dest 0x%x, memset 0x%x\n", | ||
| 167 | *(u32 *) ((u8 *) desc + 2048), | ||
| 168 | *(u32 *) ((u8 *) desc + 1024), | ||
| 169 | *(u32 *) ((u8 *) desc + 3072)); | ||
| 170 | return -1; | ||
| 171 | } | ||
| 172 | return 0; | ||
| 173 | } | ||
| 174 | |||
| 175 | static struct device dummy_dma_dev = { | ||
| 176 | .bus_id = "fallback device", | ||
| 177 | .coherent_dma_mask = DMA_64BIT_MASK, | ||
| 178 | .dma_mask = &dummy_dma_dev.coherent_dma_mask, | ||
| 179 | }; | ||
| 180 | |||
| 181 | /* Setup and initialize I/O AT */ | ||
| 182 | /* This driver needs I/O AT as the throttling takes effect only when there is | ||
| 183 | * some memory activity. We use I/O AT to set up a dummy copy, while all CPUs | ||
| 184 | * go idle and memory is throttled. | ||
| 185 | */ | ||
| 186 | static int __init i7300_idle_ioat_init(void) | ||
| 187 | { | ||
| 188 | u8 ver, chan_count, ioat_chan; | ||
| 189 | u16 chan_ctl; | ||
| 190 | |||
| 191 | ioat_iomap = (u8 *) ioremap_nocache(pci_resource_start(ioat_dev, 0), | ||
| 192 | pci_resource_len(ioat_dev, 0)); | ||
| 193 | |||
| 194 | if (!ioat_iomap) { | ||
| 195 | printk(KERN_ERR I7300_PRINT "failed to map I/O AT registers\n"); | ||
| 196 | goto err_ret; | ||
| 197 | } | ||
| 198 | |||
| 199 | ver = readb(ioat_iomap + IOAT_VER_OFFSET); | ||
| 200 | if (ver != IOAT_VER_1_2) { | ||
| 201 | printk(KERN_ERR I7300_PRINT "unknown I/O AT version (%u.%u)\n", | ||
| 202 | ver >> 4, ver & 0xf); | ||
| 203 | goto err_unmap; | ||
| 204 | } | ||
| 205 | |||
| 206 | chan_count = readb(ioat_iomap + IOAT_CHANCNT_OFFSET); | ||
| 207 | if (!chan_count) { | ||
| 208 | printk(KERN_ERR I7300_PRINT "unexpected # of I/O AT channels " | ||
| 209 | "(%u)\n", | ||
| 210 | chan_count); | ||
| 211 | goto err_unmap; | ||
| 212 | } | ||
| 213 | |||
| 214 | ioat_chan = chan_count - 1; | ||
| 215 | ioat_chanbase = IOAT_CHANBASE(ioat_iomap, ioat_chan); | ||
| 216 | |||
| 217 | chan_ctl = readw(ioat_chanbase + IOAT_CHANCTRL_OFFSET); | ||
| 218 | if (chan_ctl & IOAT_CHANCTRL_CHANNEL_IN_USE) { | ||
| 219 | printk(KERN_ERR I7300_PRINT "channel %d in use\n", ioat_chan); | ||
| 220 | goto err_unmap; | ||
| 221 | } | ||
| 222 | |||
| 223 | writew(IOAT_CHANCTRL_CHANNEL_IN_USE, | ||
| 224 | ioat_chanbase + IOAT_CHANCTRL_OFFSET); | ||
| 225 | |||
| 226 | ioat_desc = (struct ioat_dma_descriptor *)dma_alloc_coherent( | ||
| 227 | &dummy_dma_dev, 4096, | ||
| 228 | (dma_addr_t *)&ioat_desc_phys, GFP_KERNEL); | ||
| 229 | if (!ioat_desc) { | ||
| 230 | printk(KERN_ERR I7300_PRINT "failed to allocate I/O AT desc\n"); | ||
| 231 | goto err_mark_unused; | ||
| 232 | } | ||
| 233 | |||
| 234 | writel(ioat_desc_phys & 0xffffffffUL, | ||
| 235 | ioat_chanbase + IOAT1_CHAINADDR_OFFSET_LOW); | ||
| 236 | writel(ioat_desc_phys >> 32, | ||
| 237 | ioat_chanbase + IOAT1_CHAINADDR_OFFSET_HIGH); | ||
| 238 | |||
| 239 | if (i7300_idle_ioat_selftest(ioat_iomap, ioat_desc, ioat_desc_phys)) { | ||
| 240 | printk(KERN_ERR I7300_PRINT "I/O AT self-test failed\n"); | ||
| 241 | goto err_free; | ||
| 242 | } | ||
| 243 | |||
| 244 | /* Setup circular I/O AT descriptor chain */ | ||
| 245 | ioat_desc[0].ctl = IOAT_DESC_SADDR_SNP_CTL | IOAT_DESC_DADDR_SNP_CTL; | ||
| 246 | ioat_desc[0].src_addr = ioat_desc_phys + 2048; | ||
| 247 | ioat_desc[0].dst_addr = ioat_desc_phys + 3072; | ||
| 248 | ioat_desc[0].size = 128; | ||
| 249 | ioat_desc[0].next = ioat_desc_phys + sizeof(struct ioat_dma_descriptor); | ||
| 250 | |||
| 251 | ioat_desc[1].ctl = ioat_desc[0].ctl; | ||
| 252 | ioat_desc[1].src_addr = ioat_desc[0].src_addr; | ||
| 253 | ioat_desc[1].dst_addr = ioat_desc[0].dst_addr; | ||
| 254 | ioat_desc[1].size = ioat_desc[0].size; | ||
| 255 | ioat_desc[1].next = ioat_desc_phys; | ||
| 256 | |||
| 257 | return 0; | ||
| 258 | |||
| 259 | err_free: | ||
| 260 | dma_free_coherent(&dummy_dma_dev, 4096, (void *)ioat_desc, 0); | ||
| 261 | err_mark_unused: | ||
| 262 | writew(0, ioat_chanbase + IOAT_CHANCTRL_OFFSET); | ||
| 263 | err_unmap: | ||
| 264 | iounmap(ioat_iomap); | ||
| 265 | err_ret: | ||
| 266 | return -ENODEV; | ||
| 267 | } | ||
| 268 | |||
| 269 | /* Cleanup I/O AT */ | ||
| 270 | static void __exit i7300_idle_ioat_exit(void) | ||
| 271 | { | ||
| 272 | int i; | ||
| 273 | u64 chan_sts; | ||
| 274 | |||
| 275 | i7300_idle_ioat_stop(); | ||
| 276 | |||
| 277 | /* Wait for a while for the channel to halt before releasing */ | ||
| 278 | for (i = 0; i < 10; i++) { | ||
| 279 | writeb(IOAT_CHANCMD_RESET, | ||
| 280 | ioat_chanbase + IOAT1_CHANCMD_OFFSET); | ||
| 281 | |||
| 282 | chan_sts = readq(ioat_chanbase + IOAT1_CHANSTS_OFFSET) & | ||
| 283 | IOAT_CHANSTS_DMA_TRANSFER_STATUS; | ||
| 284 | |||
| 285 | if (chan_sts != IOAT_CHANSTS_DMA_TRANSFER_STATUS_ACTIVE) { | ||
| 286 | writew(0, ioat_chanbase + IOAT_CHANCTRL_OFFSET); | ||
| 287 | break; | ||
| 288 | } | ||
| 289 | udelay(1000); | ||
| 290 | } | ||
| 291 | |||
| 292 | chan_sts = readq(ioat_chanbase + IOAT1_CHANSTS_OFFSET) & | ||
| 293 | IOAT_CHANSTS_DMA_TRANSFER_STATUS; | ||
| 294 | |||
| 295 | /* | ||
| 296 | * We tried to reset multiple times. If IO A/T channel is still active | ||
| 297 | * flag an error and return without cleanup. Memory leak is better | ||
| 298 | * than random corruption in that extreme error situation. | ||
| 299 | */ | ||
| 300 | if (chan_sts == IOAT_CHANSTS_DMA_TRANSFER_STATUS_ACTIVE) { | ||
| 301 | printk(KERN_ERR I7300_PRINT "Unable to stop IO A/T channels." | ||
| 302 | " Not freeing resources\n"); | ||
| 303 | return; | ||
| 304 | } | ||
| 305 | |||
| 306 | dma_free_coherent(&dummy_dma_dev, 4096, (void *)ioat_desc, 0); | ||
| 307 | iounmap(ioat_iomap); | ||
| 308 | } | ||
| 309 | |||
| 310 | /* End: I/O AT Helper routines */ | ||
| 311 | |||
| 312 | #define DIMM_THRTLOW 0x64 | ||
| 313 | #define DIMM_THRTCTL 0x67 | ||
| 314 | #define DIMM_THRTCTL_THRMHUNT (1UL << 0) | ||
| 315 | #define DIMM_MC 0x40 | ||
| 316 | #define DIMM_GTW_MODE (1UL << 17) | ||
| 317 | #define DIMM_GBLACT 0x60 | ||
| 318 | |||
| 319 | /* | ||
| 320 | * Keep track of an exponential-decaying average of recent idle durations. | ||
| 321 | * The latest duration gets DURATION_WEIGHT_PCT percentage weight | ||
| 322 | * in this average, with the old average getting the remaining weight. | ||
| 323 | * | ||
| 324 | * High weights emphasize recent history, low weights include long history. | ||
| 325 | */ | ||
| 326 | #define DURATION_WEIGHT_PCT 55 | ||
| 327 | |||
| 328 | /* | ||
| 329 | * When the decaying average of recent durations or the predicted duration | ||
| 330 | * of the next timer interrupt is shorter than duration_threshold, the | ||
| 331 | * driver will decline to throttle. | ||
| 332 | */ | ||
| 333 | #define DURATION_THRESHOLD_US 100 | ||
| 334 | |||
| 335 | |||
| 336 | /* Store DIMM thermal throttle configuration */ | ||
| 337 | static int i7300_idle_thrt_save(void) | ||
| 338 | { | ||
| 339 | u32 new_mc_val; | ||
| 340 | u8 gblactlm; | ||
| 341 | |||
| 342 | pci_read_config_byte(fbd_dev, DIMM_THRTCTL, &i7300_idle_thrtctl_saved); | ||
| 343 | pci_read_config_byte(fbd_dev, DIMM_THRTLOW, &i7300_idle_thrtlow_saved); | ||
| 344 | pci_read_config_dword(fbd_dev, DIMM_MC, &i7300_idle_mc_saved); | ||
| 345 | /* | ||
| 346 | * Make sure we have Global Throttling Window Mode set to have a | ||
| 347 | * "short" window. This (mostly) works around an issue where | ||
| 348 | * throttling persists until the end of the global throttling window | ||
| 349 | * size. On the tested system, this was resulting in a maximum of | ||
| 350 | * 64 ms to exit throttling (average 32 ms). The actual numbers | ||
| 351 | * depends on system frequencies. Setting the short window reduces | ||
| 352 | * this by a factor of 4096. | ||
| 353 | * | ||
| 354 | * We will only do this only if the system is set for | ||
| 355 | * unlimited-activations while in open-loop throttling (i.e., when | ||
| 356 | * Global Activation Throttle Limit is zero). | ||
| 357 | */ | ||
| 358 | pci_read_config_byte(fbd_dev, DIMM_GBLACT, &gblactlm); | ||
| 359 | dprintk("thrtctl_saved = 0x%02x, thrtlow_saved = 0x%02x\n", | ||
| 360 | i7300_idle_thrtctl_saved, | ||
| 361 | i7300_idle_thrtlow_saved); | ||
| 362 | dprintk("mc_saved = 0x%08x, gblactlm = 0x%02x\n", | ||
| 363 | i7300_idle_mc_saved, | ||
| 364 | gblactlm); | ||
| 365 | if (gblactlm == 0) { | ||
| 366 | new_mc_val = i7300_idle_mc_saved | DIMM_GTW_MODE; | ||
| 367 | pci_write_config_dword(fbd_dev, DIMM_MC, new_mc_val); | ||
| 368 | return 0; | ||
| 369 | } else { | ||
| 370 | dprintk("could not set GTW_MODE = 1 (OLTT enabled)\n"); | ||
| 371 | return -ENODEV; | ||
| 372 | } | ||
| 373 | } | ||
| 374 | |||
| 375 | /* Restore DIMM thermal throttle configuration */ | ||
| 376 | static void i7300_idle_thrt_restore(void) | ||
| 377 | { | ||
| 378 | pci_write_config_dword(fbd_dev, DIMM_MC, i7300_idle_mc_saved); | ||
| 379 | pci_write_config_byte(fbd_dev, DIMM_THRTLOW, i7300_idle_thrtlow_saved); | ||
| 380 | pci_write_config_byte(fbd_dev, DIMM_THRTCTL, i7300_idle_thrtctl_saved); | ||
| 381 | } | ||
| 382 | |||
| 383 | /* Enable DIMM thermal throttling */ | ||
| 384 | static void i7300_idle_start(void) | ||
| 385 | { | ||
| 386 | u8 new_ctl; | ||
| 387 | u8 limit; | ||
| 388 | |||
| 389 | new_ctl = i7300_idle_thrtctl_saved & ~DIMM_THRTCTL_THRMHUNT; | ||
| 390 | pci_write_config_byte(fbd_dev, DIMM_THRTCTL, new_ctl); | ||
| 391 | |||
| 392 | limit = i7300_idle_thrtlowlm; | ||
| 393 | if (unlikely(limit > MAX_THRTLWLIMIT)) | ||
| 394 | limit = MAX_THRTLWLIMIT; | ||
| 395 | |||
| 396 | pci_write_config_byte(fbd_dev, DIMM_THRTLOW, limit); | ||
| 397 | |||
| 398 | new_ctl = i7300_idle_thrtctl_saved | DIMM_THRTCTL_THRMHUNT; | ||
| 399 | pci_write_config_byte(fbd_dev, DIMM_THRTCTL, new_ctl); | ||
| 400 | } | ||
| 401 | |||
| 402 | /* Disable DIMM thermal throttling */ | ||
| 403 | static void i7300_idle_stop(void) | ||
| 404 | { | ||
| 405 | u8 new_ctl; | ||
| 406 | u8 got_ctl; | ||
| 407 | |||
| 408 | new_ctl = i7300_idle_thrtctl_saved & ~DIMM_THRTCTL_THRMHUNT; | ||
| 409 | pci_write_config_byte(fbd_dev, DIMM_THRTCTL, new_ctl); | ||
| 410 | |||
| 411 | pci_write_config_byte(fbd_dev, DIMM_THRTLOW, i7300_idle_thrtlow_saved); | ||
| 412 | pci_write_config_byte(fbd_dev, DIMM_THRTCTL, i7300_idle_thrtctl_saved); | ||
| 413 | pci_read_config_byte(fbd_dev, DIMM_THRTCTL, &got_ctl); | ||
| 414 | WARN_ON_ONCE(got_ctl != i7300_idle_thrtctl_saved); | ||
| 415 | } | ||
| 416 | |||
| 417 | |||
| 418 | /* | ||
| 419 | * i7300_avg_duration_check() | ||
| 420 | * return 0 if the decaying average of recent idle durations is | ||
| 421 | * more than DURATION_THRESHOLD_US | ||
| 422 | */ | ||
| 423 | static int i7300_avg_duration_check(void) | ||
| 424 | { | ||
| 425 | if (avg_idle_us >= DURATION_THRESHOLD_US) | ||
| 426 | return 0; | ||
| 427 | |||
| 428 | #ifdef DEBUG | ||
| 429 | past_skip++; | ||
| 430 | #endif | ||
| 431 | return 1; | ||
| 432 | } | ||
| 433 | |||
| 434 | /* Idle notifier to look at idle CPUs */ | ||
| 435 | static int i7300_idle_notifier(struct notifier_block *nb, unsigned long val, | ||
| 436 | void *data) | ||
| 437 | { | ||
| 438 | unsigned long flags; | ||
| 439 | ktime_t now_ktime; | ||
| 440 | static ktime_t idle_begin_time; | ||
| 441 | static int time_init = 1; | ||
| 442 | |||
| 443 | if (!i7300_idle_thrtlowlm) | ||
| 444 | return 0; | ||
| 445 | |||
| 446 | if (unlikely(time_init)) { | ||
| 447 | time_init = 0; | ||
| 448 | idle_begin_time = ktime_get(); | ||
| 449 | } | ||
| 450 | |||
| 451 | spin_lock_irqsave(&i7300_idle_lock, flags); | ||
| 452 | if (val == IDLE_START) { | ||
| 453 | |||
| 454 | cpu_set(smp_processor_id(), idle_cpumask); | ||
| 455 | |||
| 456 | if (cpus_weight(idle_cpumask) != num_online_cpus()) | ||
| 457 | goto end; | ||
| 458 | |||
| 459 | now_ktime = ktime_get(); | ||
| 460 | idle_begin_time = now_ktime; | ||
| 461 | |||
| 462 | if (i7300_avg_duration_check()) | ||
| 463 | goto end; | ||
| 464 | |||
| 465 | i7300_idle_active = 1; | ||
| 466 | total_starts++; | ||
| 467 | start_ktime = now_ktime; | ||
| 468 | |||
| 469 | i7300_idle_start(); | ||
| 470 | i7300_idle_ioat_start(); | ||
| 471 | |||
| 472 | } else if (val == IDLE_END) { | ||
| 473 | cpu_clear(smp_processor_id(), idle_cpumask); | ||
| 474 | if (cpus_weight(idle_cpumask) == (num_online_cpus() - 1)) { | ||
| 475 | /* First CPU coming out of idle */ | ||
| 476 | u64 idle_duration_us; | ||
| 477 | |||
| 478 | now_ktime = ktime_get(); | ||
| 479 | |||
| 480 | idle_duration_us = ktime_to_us(ktime_sub | ||
| 481 | (now_ktime, idle_begin_time)); | ||
| 482 | |||
| 483 | avg_idle_us = | ||
| 484 | ((100 - DURATION_WEIGHT_PCT) * avg_idle_us + | ||
| 485 | DURATION_WEIGHT_PCT * idle_duration_us) / 100; | ||
| 486 | |||
| 487 | if (i7300_idle_active) { | ||
| 488 | ktime_t idle_ktime; | ||
| 489 | |||
| 490 | idle_ktime = ktime_sub(now_ktime, start_ktime); | ||
| 491 | total_us += ktime_to_us(idle_ktime); | ||
| 492 | |||
| 493 | i7300_idle_ioat_stop(); | ||
| 494 | i7300_idle_stop(); | ||
| 495 | i7300_idle_active = 0; | ||
| 496 | } | ||
| 497 | } | ||
| 498 | } | ||
| 499 | end: | ||
| 500 | spin_unlock_irqrestore(&i7300_idle_lock, flags); | ||
| 501 | return 0; | ||
| 502 | } | ||
| 503 | |||
| 504 | static struct notifier_block i7300_idle_nb = { | ||
| 505 | .notifier_call = i7300_idle_notifier, | ||
| 506 | }; | ||
| 507 | |||
| 508 | /* | ||
| 509 | * I/O AT controls (PCI bus 0 device 8 function 0) | ||
| 510 | * DIMM controls (PCI bus 0 device 16 function 1) | ||
| 511 | */ | ||
| 512 | #define IOAT_BUS 0 | ||
| 513 | #define IOAT_DEVFN PCI_DEVFN(8, 0) | ||
| 514 | #define MEMCTL_BUS 0 | ||
| 515 | #define MEMCTL_DEVFN PCI_DEVFN(16, 1) | ||
| 516 | |||
| 517 | struct fbd_ioat { | ||
| 518 | unsigned int vendor; | ||
| 519 | unsigned int ioat_dev; | ||
| 520 | }; | ||
| 521 | |||
| 522 | /* | ||
| 523 | * The i5000 chip-set has the same hooks as the i7300 | ||
| 524 | * but support is disabled by default because this driver | ||
| 525 | * has not been validated on that platform. | ||
| 526 | */ | ||
| 527 | #define SUPPORT_I5000 0 | ||
| 528 | |||
| 529 | static const struct fbd_ioat fbd_ioat_list[] = { | ||
| 530 | {PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_IOAT_CNB}, | ||
| 531 | #if SUPPORT_I5000 | ||
| 532 | {PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_IOAT}, | ||
| 533 | #endif | ||
| 534 | {0, 0} | ||
| 535 | }; | ||
| 536 | |||
| 537 | /* table of devices that work with this driver */ | ||
| 538 | static const struct pci_device_id pci_tbl[] = { | ||
| 539 | { PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_FBD_CNB) }, | ||
| 540 | #if SUPPORT_I5000 | ||
| 541 | { PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_5000_ERR) }, | ||
| 542 | #endif | ||
| 543 | { } /* Terminating entry */ | ||
| 544 | }; | ||
| 545 | |||
| 546 | MODULE_DEVICE_TABLE(pci, pci_tbl); | ||
| 547 | |||
| 548 | /* Check for known platforms with I/O-AT */ | ||
| 549 | static int __init i7300_idle_platform_probe(void) | ||
| 550 | { | ||
| 551 | int i; | ||
| 552 | |||
| 553 | fbd_dev = pci_get_bus_and_slot(MEMCTL_BUS, MEMCTL_DEVFN); | ||
| 554 | if (!fbd_dev) | ||
| 555 | return -ENODEV; | ||
| 556 | |||
| 557 | for (i = 0; pci_tbl[i].vendor != 0; i++) { | ||
| 558 | if (fbd_dev->vendor == pci_tbl[i].vendor && | ||
| 559 | fbd_dev->device == pci_tbl[i].device) { | ||
| 560 | break; | ||
| 561 | } | ||
| 562 | } | ||
| 563 | if (pci_tbl[i].vendor == 0) | ||
| 564 | return -ENODEV; | ||
| 565 | |||
| 566 | ioat_dev = pci_get_bus_and_slot(IOAT_BUS, IOAT_DEVFN); | ||
| 567 | if (!ioat_dev) | ||
| 568 | return -ENODEV; | ||
| 569 | |||
| 570 | for (i = 0; fbd_ioat_list[i].vendor != 0; i++) { | ||
| 571 | if (ioat_dev->vendor == fbd_ioat_list[i].vendor && | ||
| 572 | ioat_dev->device == fbd_ioat_list[i].ioat_dev) { | ||
| 573 | return 0; | ||
| 574 | } | ||
| 575 | } | ||
| 576 | return -ENODEV; | ||
| 577 | } | ||
| 578 | |||
| 579 | int stats_open_generic(struct inode *inode, struct file *fp) | ||
| 580 | { | ||
| 581 | fp->private_data = inode->i_private; | ||
| 582 | return 0; | ||
| 583 | } | ||
| 584 | |||
| 585 | static ssize_t stats_read_ul(struct file *fp, char __user *ubuf, size_t count, | ||
| 586 | loff_t *off) | ||
| 587 | { | ||
| 588 | unsigned long *p = fp->private_data; | ||
| 589 | char buf[32]; | ||
| 590 | int len; | ||
| 591 | |||
| 592 | len = snprintf(buf, 32, "%lu\n", *p); | ||
| 593 | return simple_read_from_buffer(ubuf, count, off, buf, len); | ||
| 594 | } | ||
| 595 | |||
| 596 | static const struct file_operations idle_fops = { | ||
| 597 | .open = stats_open_generic, | ||
| 598 | .read = stats_read_ul, | ||
| 599 | }; | ||
| 600 | |||
| 601 | struct debugfs_file_info { | ||
| 602 | void *ptr; | ||
| 603 | char name[32]; | ||
| 604 | struct dentry *file; | ||
| 605 | } debugfs_file_list[] = { | ||
| 606 | {&total_starts, "total_starts", NULL}, | ||
| 607 | {&total_us, "total_us", NULL}, | ||
| 608 | #ifdef DEBUG | ||
| 609 | {&past_skip, "past_skip", NULL}, | ||
| 610 | #endif | ||
| 611 | {NULL, "", NULL} | ||
| 612 | }; | ||
| 613 | |||
| 614 | static int __init i7300_idle_init(void) | ||
| 615 | { | ||
| 616 | spin_lock_init(&i7300_idle_lock); | ||
| 617 | cpus_clear(idle_cpumask); | ||
| 618 | total_us = 0; | ||
| 619 | |||
| 620 | if (i7300_idle_platform_probe()) | ||
| 621 | return -ENODEV; | ||
| 622 | |||
| 623 | if (i7300_idle_thrt_save()) | ||
| 624 | return -ENODEV; | ||
| 625 | |||
| 626 | if (i7300_idle_ioat_init()) | ||
| 627 | return -ENODEV; | ||
| 628 | |||
| 629 | debugfs_dir = debugfs_create_dir("i7300_idle", NULL); | ||
| 630 | if (debugfs_dir) { | ||
| 631 | int i = 0; | ||
| 632 | |||
| 633 | while (debugfs_file_list[i].ptr != NULL) { | ||
| 634 | debugfs_file_list[i].file = debugfs_create_file( | ||
| 635 | debugfs_file_list[i].name, | ||
| 636 | S_IRUSR, | ||
| 637 | debugfs_dir, | ||
| 638 | debugfs_file_list[i].ptr, | ||
| 639 | &idle_fops); | ||
| 640 | i++; | ||
| 641 | } | ||
| 642 | } | ||
| 643 | |||
| 644 | idle_notifier_register(&i7300_idle_nb); | ||
| 645 | |||
| 646 | printk(KERN_INFO "i7300_idle: loaded v%s\n", I7300_IDLE_DRIVER_VERSION); | ||
| 647 | return 0; | ||
| 648 | } | ||
| 649 | |||
| 650 | static void __exit i7300_idle_exit(void) | ||
| 651 | { | ||
| 652 | idle_notifier_unregister(&i7300_idle_nb); | ||
| 653 | |||
| 654 | if (debugfs_dir) { | ||
| 655 | int i = 0; | ||
| 656 | |||
| 657 | while (debugfs_file_list[i].file != NULL) { | ||
| 658 | debugfs_remove(debugfs_file_list[i].file); | ||
| 659 | i++; | ||
| 660 | } | ||
| 661 | |||
| 662 | debugfs_remove(debugfs_dir); | ||
| 663 | } | ||
| 664 | i7300_idle_thrt_restore(); | ||
| 665 | i7300_idle_ioat_exit(); | ||
| 666 | } | ||
| 667 | |||
| 668 | module_init(i7300_idle_init); | ||
| 669 | module_exit(i7300_idle_exit); | ||
| 670 | |||
| 671 | MODULE_AUTHOR("Andy Henroid <andrew.d.henroid@intel.com>"); | ||
| 672 | MODULE_DESCRIPTION("Intel Chipset DIMM Idle Power Saving Driver v" | ||
| 673 | I7300_IDLE_DRIVER_VERSION); | ||
| 674 | MODULE_LICENSE("GPL"); | ||
