diff options
author | Bastian Hecht <hechtb@googlemail.com> | 2012-03-18 15:13:20 +0100 |
---|---|---|
committer | David Woodhouse <David.Woodhouse@intel.com> | 2012-03-27 00:53:34 +0100 |
commit | cfe781946dac7f5ff42e23cd7054c75e7201fbdc (patch) | |
tree | 75d102cf44ab8d2fe190a67594fee88790005b88 | |
parent | 42d7fbe223ab878b23de9e3b0166f8cd665a2aa5 (diff) | |
download | op-kernel-dev-cfe781946dac7f5ff42e23cd7054c75e7201fbdc.zip op-kernel-dev-cfe781946dac7f5ff42e23cd7054c75e7201fbdc.tar.gz |
mtd: sh_flctl: Add power management with QoS request
Adds power management code with fine granularity. Every flash control
command is enclosed by runtime_put()/get()s. To make sure that no
overhead is generated by too frequent power state switches, a quality of
service request is issued.
Signed-off-by: Bastian Hecht <hechtb@gmail.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
-rw-r--r-- | drivers/mtd/nand/sh_flctl.c | 51 | ||||
-rw-r--r-- | include/linux/mtd/sh_flctl.h | 3 |
2 files changed, 45 insertions, 9 deletions
diff --git a/drivers/mtd/nand/sh_flctl.c b/drivers/mtd/nand/sh_flctl.c index d0f1f3c..2ee9a1b 100644 --- a/drivers/mtd/nand/sh_flctl.c +++ b/drivers/mtd/nand/sh_flctl.c @@ -26,6 +26,7 @@ #include <linux/delay.h> #include <linux/io.h> #include <linux/platform_device.h> +#include <linux/pm_runtime.h> #include <linux/slab.h> #include <linux/mtd/mtd.h> @@ -515,6 +516,8 @@ static void flctl_cmdfunc(struct mtd_info *mtd, unsigned int command, struct sh_flctl *flctl = mtd_to_flctl(mtd); uint32_t read_cmd = 0; + pm_runtime_get_sync(&flctl->pdev->dev); + flctl->read_bytes = 0; if (command != NAND_CMD_PAGEPROG) flctl->index = 0; @@ -670,7 +673,7 @@ static void flctl_cmdfunc(struct mtd_info *mtd, unsigned int command, default: break; } - return; + goto runtime_exit; read_normal_exit: writel(flctl->read_bytes, FLDTCNTR(flctl)); /* set read size */ @@ -678,23 +681,47 @@ read_normal_exit: start_translation(flctl); read_fiforeg(flctl, flctl->read_bytes, 0); wait_completion(flctl); +runtime_exit: + pm_runtime_put_sync(&flctl->pdev->dev); return; } static void flctl_select_chip(struct mtd_info *mtd, int chipnr) { struct sh_flctl *flctl = mtd_to_flctl(mtd); + int ret; switch (chipnr) { case -1: flctl->flcmncr_base &= ~CE0_ENABLE; + + pm_runtime_get_sync(&flctl->pdev->dev); writel(flctl->flcmncr_base, FLCMNCR(flctl)); + + if (flctl->qos_request) { + dev_pm_qos_remove_request(&flctl->pm_qos); + flctl->qos_request = 0; + } + + pm_runtime_put_sync(&flctl->pdev->dev); break; case 0: flctl->flcmncr_base |= CE0_ENABLE; - writel(flctl->flcmncr_base, FLCMNCR(flctl)); - if (flctl->holden) + + if (!flctl->qos_request) { + ret = dev_pm_qos_add_request(&flctl->pdev->dev, + &flctl->pm_qos, 100); + if (ret < 0) + dev_err(&flctl->pdev->dev, + "PM QoS request failed: %d\n", ret); + flctl->qos_request = 1; + } + + if (flctl->holden) { + pm_runtime_get_sync(&flctl->pdev->dev); writel(HOLDEN, FLHOLDCR(flctl)); + pm_runtime_put_sync(&flctl->pdev->dev); + } break; default: BUG(); @@ -835,13 +862,13 @@ static int __devinit flctl_probe(struct platform_device *pdev) res = platform_get_resource(pdev, IORESOURCE_MEM, 0); if (!res) { dev_err(&pdev->dev, "failed to get I/O memory\n"); - goto err; + goto err_iomap; } flctl->reg = ioremap(res->start, resource_size(res)); if (flctl->reg == NULL) { dev_err(&pdev->dev, "failed to remap I/O memory\n"); - goto err; + goto err_iomap; } platform_set_drvdata(pdev, flctl); @@ -871,23 +898,28 @@ static int __devinit flctl_probe(struct platform_device *pdev) nand->read_word = flctl_read_word; } + pm_runtime_enable(&pdev->dev); + pm_runtime_resume(&pdev->dev); + ret = nand_scan_ident(flctl_mtd, 1, NULL); if (ret) - goto err; + goto err_chip; ret = flctl_chip_init_tail(flctl_mtd); if (ret) - goto err; + goto err_chip; ret = nand_scan_tail(flctl_mtd); if (ret) - goto err; + goto err_chip; mtd_device_register(flctl_mtd, pdata->parts, pdata->nr_parts); return 0; -err: +err_chip: + pm_runtime_disable(&pdev->dev); +err_iomap: kfree(flctl); return ret; } @@ -897,6 +929,7 @@ static int __devexit flctl_remove(struct platform_device *pdev) struct sh_flctl *flctl = platform_get_drvdata(pdev); nand_release(&flctl->mtd); + pm_runtime_disable(&pdev->dev); kfree(flctl); return 0; diff --git a/include/linux/mtd/sh_flctl.h b/include/linux/mtd/sh_flctl.h index 8bcf299..a38e1fa 100644 --- a/include/linux/mtd/sh_flctl.h +++ b/include/linux/mtd/sh_flctl.h @@ -23,6 +23,7 @@ #include <linux/mtd/mtd.h> #include <linux/mtd/nand.h> #include <linux/mtd/partitions.h> +#include <linux/pm_qos.h> /* FLCTL registers */ #define FLCMNCR(f) (f->reg + 0x0) @@ -131,6 +132,7 @@ struct sh_flctl { struct mtd_info mtd; struct nand_chip chip; struct platform_device *pdev; + struct dev_pm_qos_request pm_qos; void __iomem *reg; uint8_t done_buff[2048 + 64]; /* max size 2048 + 64 */ @@ -149,6 +151,7 @@ struct sh_flctl { unsigned page_size:1; /* NAND page size (0 = 512, 1 = 2048) */ unsigned hwecc:1; /* Hardware ECC (0 = disabled, 1 = enabled) */ unsigned holden:1; /* Hardware has FLHOLDCR and HOLDEN is set */ + unsigned qos_request:1; /* QoS request to prevent deep power shutdown */ }; struct sh_flctl_platform_data { |