diff options
Diffstat (limited to 'arch/arm/mach-ux500/pm/performance.c')
| -rw-r--r-- | arch/arm/mach-ux500/pm/performance.c | 225 |
1 files changed, 225 insertions, 0 deletions
diff --git a/arch/arm/mach-ux500/pm/performance.c b/arch/arm/mach-ux500/pm/performance.c new file mode 100644 index 00000000000..ad35f5ad07c --- /dev/null +++ b/arch/arm/mach-ux500/pm/performance.c @@ -0,0 +1,225 @@ +/* + * Copyright (C) ST-Ericsson SA 2011 + * + * License Terms: GNU General Public License v2 + * + * Author: Johan Rudholm <johan.rudholm@stericsson.com> + * Author: Jonas Aaberg <jonas.aberg@stericsson.com> + */ + +#include <linux/kernel.h> +#include <linux/genhd.h> +#include <linux/major.h> +#include <linux/cdev.h> +#include <linux/kernel_stat.h> +#include <linux/workqueue.h> +#include <linux/kernel.h> +#include <linux/mfd/dbx500-prcmu.h> +#include <linux/cpu.h> +#include <linux/pm_qos_params.h> + +#include <mach/irqs.h> + +#define WLAN_PROBE_DELAY 3000 /* 3 seconds */ +#define WLAN_LIMIT (3000/3) /* If we have more than 1000 irqs per second */ + +/* + * MMC TODO: + * o Develop a more power-aware algorithm + * o Make the parameters visible through debugfs + * o Get the value of CONFIG_MMC_BLOCK_MINORS in runtime instead, since + * it may be altered by drivers/mmc/card/block.c + */ + +/* Sample reads and writes every n ms */ +#define PERF_MMC_PROBE_DELAY 1000 +/* Read threshold, sectors/second */ +#define PERF_MMC_LIMIT_READ 10240 +/* Write threshold, sectors/second */ +#define PERF_MMC_LIMIT_WRITE 8192 +/* Nr of MMC devices */ +#define PERF_MMC_HOSTS 8 + +/* + * Rescan for new MMC devices every + * PERF_MMC_PROBE_DELAY * PERF_MMC_RESCAN_CYCLES ms + */ +#define PERF_MMC_RESCAN_CYCLES 10 + +#ifdef CONFIG_MMC_BLOCK +static struct delayed_work work_mmc; +#endif + +static struct delayed_work work_wlan_workaround; +static struct pm_qos_request_list wlan_pm_qos_latency; +static bool wlan_pm_qos_is_latency_0; + +static void wlan_load(struct work_struct *work) +{ + int cpu; + unsigned int num_irqs = 0; + static unsigned int old_num_irqs = UINT_MAX; + + for_each_online_cpu(cpu) + num_irqs += kstat_irqs_cpu(IRQ_DB8500_SDMMC1, cpu); + + if ((num_irqs > old_num_irqs) && + (num_irqs - old_num_irqs) > WLAN_LIMIT) { + prcmu_qos_update_requirement(PRCMU_QOS_ARM_OPP, + "wlan", 125); + if (!wlan_pm_qos_is_latency_0) { + /* + * The wake up latency is set to 0 to prevent + * the system from going to sleep. This improves + * the wlan throughput in DMA mode. + * The wake up latency from sleep adds ~5% overhead + * for TX in some cases. + * This change doesn't increase performance for wlan + * PIO since the CPU usage prevents sleep in this mode. + */ + pm_qos_add_request(&wlan_pm_qos_latency, + PM_QOS_CPU_DMA_LATENCY, 0); + wlan_pm_qos_is_latency_0 = true; + } + } else { + prcmu_qos_update_requirement(PRCMU_QOS_ARM_OPP, + "wlan", 25); + if (wlan_pm_qos_is_latency_0) { + pm_qos_remove_request(&wlan_pm_qos_latency); + wlan_pm_qos_is_latency_0 = false; + } + } + + old_num_irqs = num_irqs; + + schedule_delayed_work_on(0, + &work_wlan_workaround, + msecs_to_jiffies(WLAN_PROBE_DELAY)); +} + +#ifdef CONFIG_MMC_BLOCK +/* + * Loop through every CONFIG_MMC_BLOCK_MINORS'th minor device for + * MMC_BLOCK_MAJOR, get the struct gendisk for each device. Returns + * nr of found disks. Populate mmc_disks. + */ +static int scan_mmc_devices(struct gendisk *mmc_disks[]) +{ + dev_t devnr; + int i, j = 0, part; + struct gendisk *mmc_devices[256 / CONFIG_MMC_BLOCK_MINORS]; + + memset(&mmc_devices, 0, sizeof(mmc_devices)); + + for (i = 0; i * CONFIG_MMC_BLOCK_MINORS < 256; i++) { + devnr = MKDEV(MMC_BLOCK_MAJOR, i * CONFIG_MMC_BLOCK_MINORS); + mmc_devices[i] = get_gendisk(devnr, &part); + + /* Invalid capacity of device, do not add to list */ + if (!mmc_devices[i] || !get_capacity(mmc_devices[i])) + continue; + + mmc_disks[j] = mmc_devices[i]; + j++; + + if (j == PERF_MMC_HOSTS) + break; + } + + return j; +} + +/* + * Sample sectors read and written to any MMC devices, update PRCMU + * qos requirement + */ +static void mmc_load(struct work_struct *work) +{ + static unsigned long long old_sectors_read[PERF_MMC_HOSTS]; + static unsigned long long old_sectors_written[PERF_MMC_HOSTS]; + static struct gendisk *mmc_disks[PERF_MMC_HOSTS]; + static int cycle, nrdisk; + static bool old_mode; + unsigned long long sectors; + bool new_mode = false; + int i; + + if (!cycle) { + memset(&mmc_disks, 0, sizeof(mmc_disks)); + nrdisk = scan_mmc_devices(mmc_disks); + cycle = PERF_MMC_RESCAN_CYCLES; + } + cycle--; + + for (i = 0; i < nrdisk; i++) { + sectors = part_stat_read(&(mmc_disks[i]->part0), + sectors[READ]); + + if (old_sectors_read[i] && + sectors > old_sectors_read[i] && + (sectors - old_sectors_read[i]) > + PERF_MMC_LIMIT_READ) + new_mode = true; + + old_sectors_read[i] = sectors; + sectors = part_stat_read(&(mmc_disks[i]->part0), + sectors[WRITE]); + + if (old_sectors_written[i] && + sectors > old_sectors_written[i] && + (sectors - old_sectors_written[i]) > + PERF_MMC_LIMIT_WRITE) + new_mode = true; + + old_sectors_written[i] = sectors; + } + + if (!old_mode && new_mode) + prcmu_qos_update_requirement(PRCMU_QOS_ARM_OPP, + "mmc", 125); + + if (old_mode && !new_mode) + prcmu_qos_update_requirement(PRCMU_QOS_ARM_OPP, + "mmc", 25); + + old_mode = new_mode; + + schedule_delayed_work(&work_mmc, + msecs_to_jiffies(PERF_MMC_PROBE_DELAY)); + +} +#endif /* CONFIG_MMC_BLOCK */ + +static int __init performance_register(void) +{ + int ret; + +#ifdef CONFIG_MMC_BLOCK + prcmu_qos_add_requirement(PRCMU_QOS_ARM_OPP, "mmc", 25); + + INIT_DELAYED_WORK_DEFERRABLE(&work_mmc, mmc_load); + + ret = schedule_delayed_work(&work_mmc, + msecs_to_jiffies(PERF_MMC_PROBE_DELAY)); + if (ret) { + pr_err("ux500: performance: Fail to schedudle mmc work\n"); + goto out; + } +#endif + + prcmu_qos_add_requirement(PRCMU_QOS_ARM_OPP, "wlan", 25); + + INIT_DELAYED_WORK_DEFERRABLE(&work_wlan_workaround, + wlan_load); + + ret = schedule_delayed_work_on(0, + &work_wlan_workaround, + msecs_to_jiffies(WLAN_PROBE_DELAY)); + if (ret) { + pr_err("ux500: performance: Fail to schedudle wlan work\n"); + goto out; + } +out: + return ret; +} +late_initcall(performance_register); |